ARMConstantIslandPass.cpp revision 5a96b3dad2f634c9081c8b2b6c2575441dc5a2bd
19a4d2e40a02b6e5fab5ccf1c768a52c76f3aec6aBill Wendling//===-- ARMConstantIslandPass.cpp - ARM constant islands ------------------===// 2a8e2989ece6dc46df59b0768184028257f913843Evan Cheng// 3a8e2989ece6dc46df59b0768184028257f913843Evan Cheng// The LLVM Compiler Infrastructure 4a8e2989ece6dc46df59b0768184028257f913843Evan Cheng// 54ee451de366474b9c228b4e5fa573795a715216dChris Lattner// This file is distributed under the University of Illinois Open Source 64ee451de366474b9c228b4e5fa573795a715216dChris Lattner// License. See LICENSE.TXT for details. 7a8e2989ece6dc46df59b0768184028257f913843Evan Cheng// 8a8e2989ece6dc46df59b0768184028257f913843Evan Cheng//===----------------------------------------------------------------------===// 9a8e2989ece6dc46df59b0768184028257f913843Evan Cheng// 10a8e2989ece6dc46df59b0768184028257f913843Evan Cheng// This file contains a pass that splits the constant pool up into 'islands' 11a8e2989ece6dc46df59b0768184028257f913843Evan Cheng// which are scattered through-out the function. This is required due to the 12a8e2989ece6dc46df59b0768184028257f913843Evan Cheng// limited pc-relative displacements that ARM has. 13a8e2989ece6dc46df59b0768184028257f913843Evan Cheng// 14a8e2989ece6dc46df59b0768184028257f913843Evan Cheng//===----------------------------------------------------------------------===// 15a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 16a8e2989ece6dc46df59b0768184028257f913843Evan Cheng#define DEBUG_TYPE "arm-cp-islands" 17a8e2989ece6dc46df59b0768184028257f913843Evan Cheng#include "ARM.h" 18af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng#include "ARMMachineFunctionInfo.h" 19a8e2989ece6dc46df59b0768184028257f913843Evan Cheng#include "ARMInstrInfo.h" 20719510a178a910feb1db707140011c32a30992c4Evan Cheng#include "Thumb2InstrInfo.h" 21ee04a6d3a40c3017124e3fd89a0db473a2824498Evan Cheng#include "MCTargetDesc/ARMAddressingModes.h" 22a8e2989ece6dc46df59b0768184028257f913843Evan Cheng#include "llvm/CodeGen/MachineConstantPool.h" 23a8e2989ece6dc46df59b0768184028257f913843Evan Cheng#include "llvm/CodeGen/MachineFunctionPass.h" 245657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng#include "llvm/CodeGen/MachineJumpTableInfo.h" 25a8e2989ece6dc46df59b0768184028257f913843Evan Cheng#include "llvm/Target/TargetData.h" 26a8e2989ece6dc46df59b0768184028257f913843Evan Cheng#include "llvm/Target/TargetMachine.h" 27a8e2989ece6dc46df59b0768184028257f913843Evan Cheng#include "llvm/Support/Debug.h" 28c25e7581b9b8088910da31702d4ca21c4734c6d7Torok Edwin#include "llvm/Support/ErrorHandling.h" 29705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner#include "llvm/Support/raw_ostream.h" 30b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson#include "llvm/ADT/SmallSet.h" 31c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng#include "llvm/ADT/SmallVector.h" 32a8e2989ece6dc46df59b0768184028257f913843Evan Cheng#include "llvm/ADT/STLExtras.h" 33a8e2989ece6dc46df59b0768184028257f913843Evan Cheng#include "llvm/ADT/Statistic.h" 341fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach#include "llvm/Support/CommandLine.h" 35b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson#include <algorithm> 36a8e2989ece6dc46df59b0768184028257f913843Evan Chengusing namespace llvm; 37a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 38a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan ChengSTATISTIC(NumCPEs, "Number of constpool entries"); 39a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan ChengSTATISTIC(NumSplit, "Number of uncond branches inserted"); 40a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan ChengSTATISTIC(NumCBrFixed, "Number of cond branches fixed"); 41a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan ChengSTATISTIC(NumUBrFixed, "Number of uncond branches fixed"); 42a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan ChengSTATISTIC(NumTBs, "Number of table branches generated"); 43a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan ChengSTATISTIC(NumT2CPShrunk, "Number of Thumb2 constantpool instructions shrunk"); 4431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan ChengSTATISTIC(NumT2BrShrunk, "Number of Thumb2 immediate branches shrunk"); 45de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan ChengSTATISTIC(NumCBZ, "Number of CBZ / CBNZ formed"); 461fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim GrosbachSTATISTIC(NumJTMoved, "Number of jump table destination blocks moved"); 4780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim GrosbachSTATISTIC(NumJTInserted, "Number of jump table intermediate blocks inserted"); 481fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 491fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 501fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbachstatic cl::opt<bool> 51f04777b945e272ccec21c7080bd5480d78a14fd2Jim GrosbachAdjustJumpTableBlocks("arm-adjust-jump-tables", cl::Hidden, cl::init(true), 521fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach cl::desc("Adjust basic block layout to better use TB[BH]")); 53a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 54a8e2989ece6dc46df59b0768184028257f913843Evan Chengnamespace { 5588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// ARMConstantIslands - Due to limited PC-relative displacements, ARM 56a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// requires constant pool entries to be scattered among the instructions 57a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// inside a function. To do this, it completely ignores the normal LLVM 5888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// constant pool; instead, it places constants wherever it feels like with 59a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// special instructions. 60a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// 61a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// The terminology used in this pass includes: 62a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// Islands - Clumps of constants placed in the function. 63a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// Water - Potential places where an island could be formed. 64a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// CPE - A constant pool entry that has been placed somewhere, which 65a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// tracks a list of users. 666726b6d75a8b679068a58cb954ba97cf9d1690baNick Lewycky class ARMConstantIslands : public MachineFunctionPass { 67a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// BasicBlockInfo - Information about the offset and size of a single 68a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// basic block. 69a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen struct BasicBlockInfo { 70a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// Offset - Distance from the beginning of the function to the beginning 71a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// of this basic block. 72a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// 73a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// The two-byte pads required for Thumb alignment are counted as part of 74a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// the following block. 75a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen unsigned Offset; 76a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen 77a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// Size - Size of the basic block in bytes. If the block contains 78a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// inline assembly, this is a worst case estimate. 79a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// 80a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// The two-byte pads required for Thumb alignment are counted as part of 81a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// the following block (i.e., the offset and size for a padded block 82a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen /// will both be ==2 mod 4). 83a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen unsigned Size; 84a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen 85a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen /// Unalign - When non-zero, the block contains instructions (inline asm) 86a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen /// of unknown size. The real size may be smaller than Size bytes by a 87a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen /// multiple of 1 << Unalign. 88a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen uint8_t Unalign; 89a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen 90a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen /// PostAlign - When non-zero, the block terminator contains a .align 91a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen /// directive, so the end of the block is aligned to 1 << PostAlign 92a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen /// bytes. 93a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen uint8_t PostAlign; 94a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen 95a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BasicBlockInfo() : Offset(0), Size(0), Unalign(0), PostAlign(0) {} 965bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen 975bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen /// Compute the offset immediately following this block. 985bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen unsigned postOffset() const { return Offset + Size; } 99a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen }; 1008494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 101a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen std::vector<BasicBlockInfo> BBInfo; 10299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 103a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// WaterList - A sorted list of basic blocks where islands could be placed 104a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// (i.e. blocks that don't fall through to the following block, due 105a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// to a return, unreachable, or unconditional branch). 106e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<MachineBasicBlock*> WaterList; 107c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 108b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson /// NewWaterList - The subset of WaterList that was created since the 109b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson /// previous iteration by inserting unconditional branches. 110b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson SmallSet<MachineBasicBlock*, 4> NewWaterList; 111b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 112034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson typedef std::vector<MachineBasicBlock*>::iterator water_iterator; 113034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson 114a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// CPUser - One user of a constant pool, keeping the machine instruction 115a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// pointer, the constant pool being referenced, and the max displacement 116549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// allowed from the instruction to the CP. The HighWaterMark records the 117549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// highest basic block where a new CPEntry can be placed. To ensure this 118549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// pass terminates, the CP entries are initially placed at the end of the 119549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// function and then move monotonically to lower addresses. The 120549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// exception to this rule is when the current CP entry for a particular 121549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// CPUser is out of range, but there is another CP entry for the same 122549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// constant value in range. We want to use the existing in-range CP 123549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// entry, but if it later moves out of range, the search for new water 124549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// should resume where it left off. The HighWaterMark is used to record 125549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// that point. 126a8e2989ece6dc46df59b0768184028257f913843Evan Cheng struct CPUser { 127a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineInstr *MI; 128a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineInstr *CPEMI; 129549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson MachineBasicBlock *HighWaterMark; 130a8e2989ece6dc46df59b0768184028257f913843Evan Cheng unsigned MaxDisp; 1315d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool NegOk; 132d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool IsSoImm; 133d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng CPUser(MachineInstr *mi, MachineInstr *cpemi, unsigned maxdisp, 134d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool neg, bool soimm) 135549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson : MI(mi), CPEMI(cpemi), MaxDisp(maxdisp), NegOk(neg), IsSoImm(soimm) { 136549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson HighWaterMark = CPEMI->getParent(); 137549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson } 138a8e2989ece6dc46df59b0768184028257f913843Evan Cheng }; 1398494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 140a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// CPUsers - Keep track of all of the machine instructions that use various 141a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// constant pools and their max displacement. 142e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<CPUser> CPUsers; 1438494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 144c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// CPEntry - One per constant pool entry, keeping the machine instruction 145c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// pointer, the constpool index, and the number of CPUser's which 146c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// reference this entry. 147c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng struct CPEntry { 148c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineInstr *CPEMI; 149c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng unsigned CPI; 150c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng unsigned RefCount; 151c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntry(MachineInstr *cpemi, unsigned cpi, unsigned rc = 0) 152c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng : CPEMI(cpemi), CPI(cpi), RefCount(rc) {} 153c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng }; 154c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 155c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// CPEntries - Keep track of all of the constant pool entry machine 15688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// instructions. For each original constpool index (i.e. those that 15788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// existed upon entry to this pass), it keeps a vector of entries. 15888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// Original elements are cloned as we go along; the clones are 15988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// put in the vector of the original element, but have distinct CPIs. 160c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng std::vector<std::vector<CPEntry> > CPEntries; 1618494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 162af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// ImmBranch - One per immediate branch, keeping the machine instruction 163af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// pointer, conditional or unconditional, the max displacement, 164af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// and (if isCond is true) the corresponding unconditional branch 165af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// opcode. 166af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng struct ImmBranch { 167af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MachineInstr *MI; 168c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng unsigned MaxDisp : 31; 169c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng bool isCond : 1; 170af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng int UncondBr; 171c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng ImmBranch(MachineInstr *mi, unsigned maxdisp, bool cond, int ubr) 172c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng : MI(mi), MaxDisp(maxdisp), isCond(cond), UncondBr(ubr) {} 173af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng }; 174af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 1752706f9771de8e90ee6379e70afedd91892bb9c8cEvan Cheng /// ImmBranches - Keep track of all the immediate branch instructions. 176af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// 177e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<ImmBranch> ImmBranches; 178af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 179d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// PushPopMIs - Keep track of all the Thumb push / pop instructions. 180d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// 181c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng SmallVector<MachineInstr*, 4> PushPopMIs; 182d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1835657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng /// T2JumpTables - Keep track of all the Thumb2 jumptable instructions. 1845657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng SmallVector<MachineInstr*, 4> T2JumpTables; 1855657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 186d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// HasFarJump - True if any far jump instruction has been emitted during 187d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// the branch fix up pass. 188d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng bool HasFarJump; 189d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1904d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach /// HasInlineAsm - True if the function contains inline assembly. 1914d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach bool HasInlineAsm; 1924d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach 1932062875a7d8f7dd94a20d9e3a298e9e216efb4b5Chris Lattner const ARMInstrInfo *TII; 19425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng const ARMSubtarget *STI; 1958593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen ARMFunctionInfo *AFI; 196b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen bool isThumb; 197d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool isThumb1; 1985e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin bool isThumb2; 199a8e2989ece6dc46df59b0768184028257f913843Evan Cheng public: 2001997473cf72957d0e70322e2fe6fe2ab141c58a6Devang Patel static char ID; 20190c579de5a383cee278acc3f7e7b9d0a656e6a35Owen Anderson ARMConstantIslands() : MachineFunctionPass(ID) {} 202794fd75c67a2cdc128d67342c6d88a504d186896Devang Patel 2035657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng virtual bool runOnMachineFunction(MachineFunction &MF); 204a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 205a8e2989ece6dc46df59b0768184028257f913843Evan Cheng virtual const char *getPassName() const { 206af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng return "ARM constant island placement and branch shortening pass"; 207a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 2088494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 209a8e2989ece6dc46df59b0768184028257f913843Evan Cheng private: 2105657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng void DoInitialPlacement(MachineFunction &MF, 211e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<MachineInstr*> &CPEMIs); 212c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntry *findConstPoolEntry(unsigned CPI, const MachineInstr *CPEMI); 21380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach void JumpTableFunctionScan(MachineFunction &MF); 2145657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng void InitialFunctionScan(MachineFunction &MF, 215e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng const std::vector<MachineInstr*> &CPEMIs); 2160c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng MachineBasicBlock *SplitBlockBeforeInstr(MachineInstr *MI); 217a8e2989ece6dc46df59b0768184028257f913843Evan Cheng void UpdateForInsertedWaterBlock(MachineBasicBlock *NewBB); 2182fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen void AdjustBBOffsetsAfter(MachineBasicBlock *BB); 219ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng bool DecrementOldEntry(unsigned CPI, MachineInstr* CPEMI); 22088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen int LookForExistingCPEntry(CPUser& U, unsigned UserOffset); 221b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson bool LookForWater(CPUser&U, unsigned UserOffset, water_iterator &WaterIter); 222b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen void CreateNewWater(unsigned CPUserIndex, unsigned UserOffset, 223757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson MachineBasicBlock *&NewMBB); 2245657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool HandleConstantPoolUser(MachineFunction &MF, unsigned CPUserIndex); 225ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng void RemoveDeadCPEMI(MachineInstr *CPEMI); 226ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng bool RemoveUnusedCPEntries(); 2278494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson bool CPEIsInRange(MachineInstr *MI, unsigned UserOffset, 2285d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng MachineInstr *CPEMI, unsigned Disp, bool NegOk, 2295d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool DoDump = false); 23099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen bool WaterIsInRange(unsigned UserOffset, MachineBasicBlock *Water, 2315d9c4b60204d741c213456e21b87e9af6a3dc627Dale Johannesen CPUser &U); 23299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen bool OffsetIsInRange(unsigned UserOffset, unsigned TrialOffset, 233d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng unsigned Disp, bool NegativeOK, bool IsSoImm = false); 234c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng bool BBIsInRange(MachineInstr *MI, MachineBasicBlock *BB, unsigned Disp); 2355657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool FixUpImmediateBr(MachineFunction &MF, ImmBranch &Br); 2365657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool FixUpConditionalBr(MachineFunction &MF, ImmBranch &Br); 2375657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool FixUpUnconditionalBr(MachineFunction &MF, ImmBranch &Br); 238d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng bool UndoLRSpillRestore(); 239a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng bool OptimizeThumb2Instructions(MachineFunction &MF); 240a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng bool OptimizeThumb2Branches(MachineFunction &MF); 24180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach bool ReorderThumb2JumpTables(MachineFunction &MF); 2425657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool OptimizeThumb2JumpTables(MachineFunction &MF); 2431fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineBasicBlock *AdjustJTTargetBlockForward(MachineBasicBlock *BB, 2441fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineBasicBlock *JTBB); 245a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 246a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen void ComputeBlockSize(const MachineBasicBlock *MBB); 247a8e2989ece6dc46df59b0768184028257f913843Evan Cheng unsigned GetOffsetOf(MachineInstr *MI) const; 2488593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen void dumpBBs(); 2495657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng void verify(MachineFunction &MF); 250a8e2989ece6dc46df59b0768184028257f913843Evan Cheng }; 2511997473cf72957d0e70322e2fe6fe2ab141c58a6Devang Patel char ARMConstantIslands::ID = 0; 252a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 253a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 2548593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// verify - check BBOffsets, BBSizes, alignment of islands 2555657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengvoid ARMConstantIslands::verify(MachineFunction &MF) { 256a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen for (unsigned i = 1, e = BBInfo.size(); i != e; ++i) 2575bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen assert(BBInfo[i-1].postOffset() == BBInfo[i].Offset); 258d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (!isThumb) 259d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return; 260d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng#ifndef NDEBUG 2615657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 262d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MBBI != E; ++MBBI) { 263d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MachineBasicBlock *MBB = MBBI; 264d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (!MBB->empty() && 265d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MBB->begin()->getOpcode() == ARM::CONSTPOOL_ENTRY) { 266d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng unsigned MBBId = MBB->getNumber(); 2674d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach assert(HasInlineAsm || 268a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen (BBInfo[MBBId].Offset%4 == 0 && BBInfo[MBBId].Size%4 == 0) || 269a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen (BBInfo[MBBId].Offset%4 != 0 && BBInfo[MBBId].Size%4 != 0)); 2708593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 2718593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 2724d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach for (unsigned i = 0, e = CPUsers.size(); i != e; ++i) { 2734d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach CPUser &U = CPUsers[i]; 2744d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach unsigned UserOffset = GetOffsetOf(U.MI) + (isThumb ? 4 : 8); 275a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach unsigned CPEOffset = GetOffsetOf(U.CPEMI); 276a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach unsigned Disp = UserOffset < CPEOffset ? CPEOffset - UserOffset : 277a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach UserOffset - CPEOffset; 278a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach assert(Disp <= U.MaxDisp || "Constant pool entry out of range!"); 2794d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach } 280a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach#endif 2818593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen} 2828593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 2838593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// print block size and offset information - debugging 2848593e418555fdae21a070357fd8734b4069c17d0Dale Johannesenvoid ARMConstantIslands::dumpBBs() { 285a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen for (unsigned J = 0, E = BBInfo.size(); J !=E; ++J) { 286a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen DEBUG(errs() << "block " << J << " offset " << BBInfo[J].Offset 287a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen << " size " << BBInfo[J].Size << "\n"); 2888593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 2898593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen} 2908593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 291af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng/// createARMConstantIslandPass - returns an instance of the constpool 292af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng/// island pass. 293a8e2989ece6dc46df59b0768184028257f913843Evan ChengFunctionPass *llvm::createARMConstantIslandPass() { 294a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return new ARMConstantIslands(); 295a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 296a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 2975657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::runOnMachineFunction(MachineFunction &MF) { 2985657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineConstantPool &MCP = *MF.getConstantPool(); 2998494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 3002062875a7d8f7dd94a20d9e3a298e9e216efb4b5Chris Lattner TII = (const ARMInstrInfo*)MF.getTarget().getInstrInfo(); 3015657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng AFI = MF.getInfo<ARMFunctionInfo>(); 30225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng STI = &MF.getTarget().getSubtarget<ARMSubtarget>(); 30325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 304b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen isThumb = AFI->isThumbFunction(); 305d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng isThumb1 = AFI->isThumb1OnlyFunction(); 3065e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin isThumb2 = AFI->isThumb2Function(); 307d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 308d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng HasFarJump = false; 3094d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach HasInlineAsm = false; 310d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 311a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Renumber all of the machine basic blocks in the function, guaranteeing that 312a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // the numbers agree with the position of the block in the function. 3135657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.RenumberBlocks(); 314a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 31580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // Try to reorder and otherwise adjust the block layout to make good use 31680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // of the TB[BH] instructions. 31780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach bool MadeChange = false; 31880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach if (isThumb2 && AdjustJumpTableBlocks) { 31980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach JumpTableFunctionScan(MF); 32080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MadeChange |= ReorderThumb2JumpTables(MF); 32180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // Data is out of date, so clear it. It'll be re-computed later. 32280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach T2JumpTables.clear(); 32380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // Blocks may have shifted around. Keep the numbering up to date. 32480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MF.RenumberBlocks(); 32580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 32680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 327d26b14c34cbcee1448b86b524578fc51cc979023Evan Cheng // Thumb1 functions containing constant pools get 4-byte alignment. 328d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // This is so we can keep exact track of where the alignment padding goes. 329d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 3307d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner // ARM and Thumb2 functions need to be 4-byte aligned. 3317d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner if (!isThumb1) 3327d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner MF.EnsureAlignment(2); // 2 = log2(4) 33356c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen 334a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Perform the initial placement of the constant pool entries. To start with, 335a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // we put them all at the end of the function. 336e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<MachineInstr*> CPEMIs; 33756c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen if (!MCP.isEmpty()) { 3385657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng DoInitialPlacement(MF, CPEMIs); 339d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (isThumb1) 3407d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner MF.EnsureAlignment(2); // 2 = log2(4) 34156c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen } 3428494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 343a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// The next UID to take is the first unused one. 3445de5d4b6d0eb3fd379fa571d82f6fa764460b3b8Evan Cheng AFI->initPICLabelUId(CPEMIs.size()); 3458494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 346a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Do the initial scan of the function, building up information about the 347a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // sizes of each block, the location of all the water, and finding all of the 348a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // constant pool users. 3495657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng InitialFunctionScan(MF, CPEMIs); 350a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CPEMIs.clear(); 3518086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen DEBUG(dumpBBs()); 3528086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 3538494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 354ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng /// Remove dead constant pool entries. 355cd080249fc249a51d8b0021a651d8b9d4a4977e0Bill Wendling MadeChange |= RemoveUnusedCPEntries(); 356ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 357d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // Iteratively place constant pool entries and fix up branches until there 358d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // is no change. 359b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng unsigned NoCPIters = 0, NoBRIters = 0; 360d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng while (true) { 361b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng bool CPChange = false; 362a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned i = 0, e = CPUsers.size(); i != e; ++i) 363b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng CPChange |= HandleConstantPoolUser(MF, i); 364b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng if (CPChange && ++NoCPIters > 30) 365b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng llvm_unreachable("Constant Island pass failed to converge!"); 3668202010364e1bfe6111f1ce62f154499b80877fbEvan Cheng DEBUG(dumpBBs()); 36726b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach 368b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Clear NewWaterList now. If we split a block for branches, it should 369b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // appear as "new water" for the next iteration of constant pool placement. 370b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.clear(); 371b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng 372b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng bool BRChange = false; 373af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng for (unsigned i = 0, e = ImmBranches.size(); i != e; ++i) 374b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng BRChange |= FixUpImmediateBr(MF, ImmBranches[i]); 375b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng if (BRChange && ++NoBRIters > 30) 376b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng llvm_unreachable("Branch Fix Up pass failed to converge!"); 3778202010364e1bfe6111f1ce62f154499b80877fbEvan Cheng DEBUG(dumpBBs()); 378b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng 379b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng if (!CPChange && !BRChange) 380d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng break; 381d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MadeChange = true; 382d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng } 383ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 384a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // Shrink 32-bit Thumb2 branch, load, and store instructions. 385e44be6381609d31b2d8879dbd5107e01404fa475Evan Cheng if (isThumb2 && !STI->prefers32BitThumb()) 386a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MadeChange |= OptimizeThumb2Instructions(MF); 38725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 3888593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // After a while, this might be made debug-only, but it is not expensive. 3895657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng verify(MF); 3908593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 39126b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach // If LR has been forced spilled and no far jump (i.e. BL) has been issued, 39226b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach // undo the spill / restore of LR if possible. 3935657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (isThumb && !HasFarJump && AFI->isLRSpilledForFarJump()) 394d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MadeChange |= UndoLRSpillRestore(); 395d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 39698b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov // Save the mapping between original and cloned constpool entries. 39798b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov for (unsigned i = 0, e = CPEntries.size(); i != e; ++i) { 39898b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov for (unsigned j = 0, je = CPEntries[i].size(); j != je; ++j) { 39998b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov const CPEntry & CPE = CPEntries[i][j]; 40098b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov AFI->recordCPEClone(i, CPE.CPI); 40198b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov } 40298b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov } 40398b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov 404b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng DEBUG(errs() << '\n'; dumpBBs()); 405b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng 406a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo.clear(); 407a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.clear(); 408a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CPUsers.clear(); 409c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntries.clear(); 410af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng ImmBranches.clear(); 411c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng PushPopMIs.clear(); 4125657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng T2JumpTables.clear(); 413d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 414d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return MadeChange; 415a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 416a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 417a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// DoInitialPlacement - Perform the initial placement of the constant pool 418a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// entries. To start with, we put them all at the end of the function. 4195657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengvoid ARMConstantIslands::DoInitialPlacement(MachineFunction &MF, 4208494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson std::vector<MachineInstr*> &CPEMIs) { 421a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Create the basic block to hold the CPE's. 4225657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *BB = MF.CreateMachineBasicBlock(); 4235657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.push_back(BB); 4248494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 4253e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen // Mark the basic block as 4-byte aligned as required by the const-pool. 4263e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen BB->setAlignment(2); 4273e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen 428a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add all of the constants from the constant pool to the end block, use an 429a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // identity mapping of CPI's to CPE's. 430a8e2989ece6dc46df59b0768184028257f913843Evan Cheng const std::vector<MachineConstantPoolEntry> &CPs = 4315657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.getConstantPool()->getConstants(); 4328494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 4335657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const TargetData &TD = *MF.getTarget().getTargetData(); 434a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned i = 0, e = CPs.size(); i != e; ++i) { 435777d2306b36816a53bc1ae1244c0dc7d998ae691Duncan Sands unsigned Size = TD.getTypeAllocSize(CPs[i].getType()); 436a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Verify that all constant pool entries are a multiple of 4 bytes. If not, 437a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // we would have to pad them out or something so that instructions stay 438a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // aligned. 439a8e2989ece6dc46df59b0768184028257f913843Evan Cheng assert((Size & 3) == 0 && "CP Entry not multiple of 4 bytes!"); 440a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineInstr *CPEMI = 441c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(BB, DebugLoc(), TII->get(ARM::CONSTPOOL_ENTRY)) 442c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner .addImm(i).addConstantPoolIndex(i).addImm(Size); 443a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CPEMIs.push_back(CPEMI); 444c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 445c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Add a new CPEntry, but no corresponding CPUser yet. 446c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng std::vector<CPEntry> CPEs; 447c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEs.push_back(CPEntry(CPEMI, i)); 448c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntries.push_back(CPEs); 449fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCPEs; 450893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Moved CPI#" << i << " to end of function as #" << i 451893e1c90a03a53cf13f73849324e83612688428aChris Lattner << "\n"); 452a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 453a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 454a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 45588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// BBHasFallthrough - Return true if the specified basic block can fallthrough 456a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// into the block immediately after it. 457a8e2989ece6dc46df59b0768184028257f913843Evan Chengstatic bool BBHasFallthrough(MachineBasicBlock *MBB) { 458a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Get the next machine basic block in the function. 459a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineFunction::iterator MBBI = MBB; 46018f30e6f5e80787808fe1455742452a5210afe07Jim Grosbach // Can't fall off end of function. 46118f30e6f5e80787808fe1455742452a5210afe07Jim Grosbach if (llvm::next(MBBI) == MBB->getParent()->end()) 462a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return false; 4638494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 4647896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineBasicBlock *NextBB = llvm::next(MBBI); 465a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::succ_iterator I = MBB->succ_begin(), 466a8e2989ece6dc46df59b0768184028257f913843Evan Cheng E = MBB->succ_end(); I != E; ++I) 467a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (*I == NextBB) 468a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return true; 4698494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 470a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return false; 471a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 472a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 473c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// findConstPoolEntry - Given the constpool index and CONSTPOOL_ENTRY MI, 474c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// look up the corresponding CPEntry. 475c99ef085b90b32952b484e8843fb66ad65215b61Evan ChengARMConstantIslands::CPEntry 476c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng*ARMConstantIslands::findConstPoolEntry(unsigned CPI, 477c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng const MachineInstr *CPEMI) { 478c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng std::vector<CPEntry> &CPEs = CPEntries[CPI]; 479c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Number of entries per constpool index should be small, just do a 480c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // linear search. 481c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng for (unsigned i = 0, e = CPEs.size(); i != e; ++i) { 482c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng if (CPEs[i].CPEMI == CPEMI) 483c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return &CPEs[i]; 484c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng } 485c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return NULL; 486c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng} 487c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 48880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// JumpTableFunctionScan - Do a scan of the function, building up 48980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// information about the sizes of each block and the locations of all 49080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// the jump tables. 49180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbachvoid ARMConstantIslands::JumpTableFunctionScan(MachineFunction &MF) { 49280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 49380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MBBI != E; ++MBBI) { 49480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock &MBB = *MBBI; 49580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 49680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 49708cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach I != E; ++I) 4985a96b3dad2f634c9081c8b2b6c2575441dc5a2bdEvan Cheng if (I->isBranch() && I->getOpcode() == ARM::t2BR_JT) 49908cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach T2JumpTables.push_back(I); 50080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 50180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach} 50280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 503a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// InitialFunctionScan - Do the initial scan of the function, building up 504a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// information about the sizes of each block, the location of all the water, 505a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// and finding all of the constant pool users. 5065657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengvoid ARMConstantIslands::InitialFunctionScan(MachineFunction &MF, 507e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng const std::vector<MachineInstr*> &CPEMIs) { 5084d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // First thing, see if the function has any inline assembly in it. If so, 5094d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // we have to be conservative about alignment assumptions, as we don't 5104d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // know for sure the size of any instructions in the inline assembly. 5114d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 5124d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach MBBI != E; ++MBBI) { 5134d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach MachineBasicBlock &MBB = *MBBI; 5144d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 5154d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach I != E; ++I) 5164d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach if (I->getOpcode() == ARM::INLINEASM) 5174d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach HasInlineAsm = true; 5184d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach } 5194d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach 520a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBInfo.clear(); 521a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBInfo.resize(MF.getNumBlockIDs()); 522a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen 5239a4d2e40a02b6e5fab5ccf1c768a52c76f3aec6aBill Wendling // Now go back through the instructions and build up our data structures. 52499c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned Offset = 0; 5255657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 526a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MBBI != E; ++MBBI) { 527a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock &MBB = *MBBI; 528a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BasicBlockInfo &BBI = BBInfo[MBB.getNumber()]; 529a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBI.Offset = Offset; 5308494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 531a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // If this block doesn't fall through into the next MBB, then this is 532a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // 'water' that a constant pool island could be placed. 533a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (!BBHasFallthrough(&MBB)) 534a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.push_back(&MBB); 5358494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 536a8e2989ece6dc46df59b0768184028257f913843Evan Cheng unsigned MBBSize = 0; 537a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 538a8e2989ece6dc46df59b0768184028257f913843Evan Cheng I != E; ++I) { 5399cfcfeb24bf7182d40d8e8a54e350451b67a1136Jim Grosbach if (I->isDebugValue()) 5409cfcfeb24bf7182d40d8e8a54e350451b67a1136Jim Grosbach continue; 541a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add instruction size to MBBSize. 54252e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray MBBSize += TII->GetInstSizeInBytes(I); 543a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 544a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen // For inline asm, GetInstSizeInBytes returns a conservative estimate. 545a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen // The actual size may be smaller, but still a multiple of the instr size. 546a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen if (I->isInlineAsm()) 547a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBI.Unalign = isThumb ? 1 : 2; 548a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen 549af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng int Opc = I->getOpcode(); 5505a96b3dad2f634c9081c8b2b6c2575441dc5a2bdEvan Cheng if (I->isBranch()) { 551af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng bool isCond = false; 552af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng unsigned Bits = 0; 553af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng unsigned Scale = 1; 554af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng int UOpc = Opc; 555af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng switch (Opc) { 5565657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng default: 5575657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; // Ignore other JT branches 5588593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen case ARM::tBR_JTr: 55966ac53165e17b7c76b8c69e57bde623d44ec492eEvan Cheng // A Thumb1 table jump may involve padding; for the offsets to 5608593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // be right, functions containing these must be 4-byte aligned. 561b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng // tBR_JTr expands to a mov pc followed by .align 2 and then the jump 5626fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // table entries. So this code checks whether offset of tBR_JTr + 2 5636fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // is aligned. That is held in Offset+MBBSize, which already has 5646fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // 2 added in for the size of the mov pc instruction. 5657d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner MF.EnsureAlignment(2U); 566a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBI.PostAlign = 2; 5676fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen if ((Offset+MBBSize)%4 != 0 || HasInlineAsm) 5686fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // FIXME: Add a pseudo ALIGN instruction instead. 5696fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen MBBSize += 2; // padding 5708593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen continue; // Does not get an entry in ImmBranches 5715657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng case ARM::t2BR_JT: 5725657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng T2JumpTables.push_back(I); 5735657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; // Does not get an entry in ImmBranches 574af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::Bcc: 575af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng isCond = true; 576af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng UOpc = ARM::B; 577af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // Fallthrough 578af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::B: 579af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 24; 580af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 4; 581af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 582af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::tBcc: 583af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng isCond = true; 584af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng UOpc = ARM::tB; 585af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 8; 586af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 2; 587af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 588af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::tB: 589af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 11; 590af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 2; 591af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 5925e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::t2Bcc: 5935e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin isCond = true; 5945e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin UOpc = ARM::t2B; 5955e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Bits = 20; 5965e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Scale = 2; 5975e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin break; 5985e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::t2B: 5995e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Bits = 24; 6005e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Scale = 2; 6015e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin break; 602af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng } 603b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng 604b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng // Record this immediate branch. 605bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng unsigned MaxOffs = ((1 << (Bits-1))-1) * Scale; 606b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng ImmBranches.push_back(ImmBranch(I, MaxOffs, isCond, UOpc)); 607af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng } 608af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 609d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng if (Opc == ARM::tPUSH || Opc == ARM::tPOP_RET) 610d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng PushPopMIs.push_back(I); 611d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 612d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (Opc == ARM::CONSTPOOL_ENTRY) 613d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng continue; 614d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 615a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Scan the instructions for constant pool operands. 616a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned op = 0, e = I->getNumOperands(); op != e; ++op) 617d735b8019b0f297d7c14b55adcd887af24d8e602Dan Gohman if (I->getOperand(op).isCPI()) { 618a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // We found one. The addressing mode tells us the max displacement 619a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // from the PC that this instruction permits. 6208494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 621a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Basic size info comes from the TSFlags field. 622b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng unsigned Bits = 0; 623b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng unsigned Scale = 1; 6245d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool NegOk = false; 625d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool IsSoImm = false; 626d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 627d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng switch (Opc) { 6288494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson default: 629c23197a26f34f559ea9797de51e187087c039c42Torok Edwin llvm_unreachable("Unknown addressing mode for CP reference!"); 630a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 631d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 632d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // Taking the address of a CP entry. 633d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::LEApcrel: 634d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // This takes a SoImm, which is 8 bit immediate rotated. We'll 635d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // pretend the maximum offset is 255 * 4. Since each instruction 636dec6de92d1425c88f319179fb4a0b0a23f781df9Jim Grosbach // 4 byte wide, this is always correct. We'll check for other 637d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // displacements that fits in a SoImm as well. 638d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 8; 639d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; 6405d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng NegOk = true; 641d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng IsSoImm = true; 642a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 6436b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson case ARM::t2LEApcrel: 644d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 12; 6455d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng NegOk = true; 646a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 647d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::tLEApcrel: 648b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Bits = 8; 649d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; 650a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 651d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 6523e5561247202bae994dd259a2d8dc4eff8f799f3Jim Grosbach case ARM::LDRi12: 653d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::LDRcp: 654971b83b67a9812556cdb97bb58aa96fb37af458dOwen Anderson case ARM::t2LDRpci: 655d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 12; // +-offset_12 656d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng NegOk = true; 657a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 658d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 659d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::tLDRpci: 660b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Bits = 8; 661b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Scale = 4; // +(offset_8*4) 662012f2d97b78e4eb9128f1d491f2c177768dbe527Evan Cheng break; 663d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 664e5165490b7ba24bb2f3043399e0d60e7f3bcf8a5Jim Grosbach case ARM::VLDRD: 665e5165490b7ba24bb2f3043399e0d60e7f3bcf8a5Jim Grosbach case ARM::VLDRS: 666d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 8; 667d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; // +-(offset_8*4) 668d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng NegOk = true; 669055b0310f862b91f33699037ce67d3ab8137c20cEvan Cheng break; 670a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 671b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng 672a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Remember that this is a user of a CP entry. 6738aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner unsigned CPI = I->getOperand(op).getIndex(); 674c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineInstr *CPEMI = CPEMIs[CPI]; 67531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned MaxOffs = ((1 << Bits)-1) * Scale; 676d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng CPUsers.push_back(CPUser(I, CPEMI, MaxOffs, NegOk, IsSoImm)); 677c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 678c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Increment corresponding CPEntry reference count. 679c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntry *CPE = findConstPoolEntry(CPI, CPEMI); 680c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng assert(CPE && "Cannot find a corresponding CPEntry!"); 681c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPE->RefCount++; 6828494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 683a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Instructions can only use one CP entry, don't bother scanning the 684a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // rest of the operands. 685a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 686a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 687a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 6882021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng 6898593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // In thumb mode, if this block is a constpool island, we may need padding 6908593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // so it's aligned on 4 byte boundary. 691b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (isThumb && 69205cc424082f797c5820b19f29f398c9cce9b9928Evan Cheng !MBB.empty() && 6938593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen MBB.begin()->getOpcode() == ARM::CONSTPOOL_ENTRY && 6944d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach ((Offset%4) != 0 || HasInlineAsm)) 6952021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng MBBSize += 2; 6962021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng 697a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBI.Size = MBBSize; 69899c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen Offset += MBBSize; 699a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 700a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 701a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 702a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen/// ComputeBlockSize - Compute the size and some alignment information for MBB. 703a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen/// This function updates BBInfo directly. 704a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesenvoid ARMConstantIslands::ComputeBlockSize(const MachineBasicBlock *MBB) { 705a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BasicBlockInfo &BBI = BBInfo[MBB->getNumber()]; 706a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBI.Size = 0; 707a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBI.Unalign = 0; 708a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBI.PostAlign = 0; 709a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen 710a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen for (MachineBasicBlock::const_iterator I = MBB->begin(), E = MBB->end(); 711a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen I != E; ++I) { 712a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBI.Size += TII->GetInstSizeInBytes(I); 713a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen // For inline asm, GetInstSizeInBytes returns a conservative estimate. 714a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen // The actual size may be smaller, but still a multiple of the instr size. 715a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen if (I->isInlineAsm()) 716a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBI.Unalign = isThumb ? 1 : 2; 717a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen } 718a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen 719a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen // tBR_JTr contains a .align 2 directive. 720a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen if (!MBB->empty() && MBB->back().getOpcode() == ARM::tBR_JTr) 721a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen BBI.PostAlign = 2; 722a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen} 723a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen 724a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// GetOffsetOf - Return the current offset of the specified machine instruction 725a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// from the start of the function. This offset changes as stuff is moved 726a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// around inside the function. 727a8e2989ece6dc46df59b0768184028257f913843Evan Chengunsigned ARMConstantIslands::GetOffsetOf(MachineInstr *MI) const { 728a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 7298494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 730a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // The offset is composed of two things: the sum of the sizes of all MBB's 731a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // before this instruction's block, and the offset from the start of the block 732a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // it is in. 733a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen unsigned Offset = BBInfo[MBB->getNumber()].Offset; 734a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 7358593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // If we're looking for a CONSTPOOL_ENTRY in Thumb, see if this block has 7368593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // alignment padding, and compensate if so. 7378494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson if (isThumb && 7388494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MI->getOpcode() == ARM::CONSTPOOL_ENTRY && 7394d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach (Offset%4 != 0 || HasInlineAsm)) 7408593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen Offset += 2; 7418593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 742a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Sum instructions before MI in MBB. 743a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::iterator I = MBB->begin(); ; ++I) { 744a8e2989ece6dc46df59b0768184028257f913843Evan Cheng assert(I != MBB->end() && "Didn't find MI in its own basic block?"); 745a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (&*I == MI) return Offset; 74652e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray Offset += TII->GetInstSizeInBytes(I); 747a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 748a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 749a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 750a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// CompareMBBNumbers - Little predicate function to sort the WaterList by MBB 751a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// ID. 752a8e2989ece6dc46df59b0768184028257f913843Evan Chengstatic bool CompareMBBNumbers(const MachineBasicBlock *LHS, 753a8e2989ece6dc46df59b0768184028257f913843Evan Cheng const MachineBasicBlock *RHS) { 754a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return LHS->getNumber() < RHS->getNumber(); 755a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 756a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 757a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// UpdateForInsertedWaterBlock - When a block is newly inserted into the 758a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// machine function, it upsets all of the block numbers. Renumber the blocks 759a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// and update the arrays that parallel this numbering. 760a8e2989ece6dc46df59b0768184028257f913843Evan Chengvoid ARMConstantIslands::UpdateForInsertedWaterBlock(MachineBasicBlock *NewBB) { 761ab4c366274a582dd8146b2820c6b999cad5fce36Duncan Sands // Renumber the MBB's to keep them consecutive. 762a8e2989ece6dc46df59b0768184028257f913843Evan Cheng NewBB->getParent()->RenumberBlocks(NewBB); 7638494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 764a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen // Insert an entry into BBInfo to align it properly with the (newly 765a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // renumbered) block numbers. 766a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo.insert(BBInfo.begin() + NewBB->getNumber(), BasicBlockInfo()); 7678494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 7688494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // Next, update WaterList. Specifically, we need to add NewMBB as having 769a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // available water after it. 770034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson water_iterator IP = 771a8e2989ece6dc46df59b0768184028257f913843Evan Cheng std::lower_bound(WaterList.begin(), WaterList.end(), NewBB, 772a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CompareMBBNumbers); 773a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.insert(IP, NewBB); 774a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 775a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 776a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 777a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// Split the basic block containing MI into two blocks, which are joined by 778b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson/// an unconditional branch. Update data structures and renumber blocks to 7790c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng/// account for this change and returns the newly created block. 7800c61584d05894a5543f690803191a8b0da05b8fcEvan ChengMachineBasicBlock *ARMConstantIslands::SplitBlockBeforeInstr(MachineInstr *MI) { 781a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock *OrigBB = MI->getParent(); 7828e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MachineFunction &MF = *OrigBB->getParent(); 783a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 784a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Create a new MBB for the code after the OrigBB. 7858494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MachineBasicBlock *NewBB = 7868494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MF.CreateMachineBasicBlock(OrigBB->getBasicBlock()); 787a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineFunction::iterator MBBI = OrigBB; ++MBBI; 7888e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MF.insert(MBBI, NewBB); 7898494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 790a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Splice the instructions starting with MI over to NewBB. 791a8e2989ece6dc46df59b0768184028257f913843Evan Cheng NewBB->splice(NewBB->end(), OrigBB, MI, OrigBB->end()); 7928494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 793a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add an unconditional branch from OrigBB to NewBB. 794a9b8b8d62c67e96bc4dc2ed25298c539102f8638Evan Cheng // Note the new unconditional branch is not being recorded. 795b67284057ee130114055309eabe0bcd1af13777dDale Johannesen // There doesn't seem to be meaningful DebugInfo available; this doesn't 796b67284057ee130114055309eabe0bcd1af13777dDale Johannesen // correspond to anything in the source. 79758541fd62707b6856beee3db9e254b0110607bb1Evan Cheng unsigned Opc = isThumb ? (isThumb2 ? ARM::t2B : ARM::tB) : ARM::B; 79851f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson if (!isThumb) 79951f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(OrigBB, DebugLoc(), TII->get(Opc)).addMBB(NewBB); 80051f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson else 80151f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(OrigBB, DebugLoc(), TII->get(Opc)).addMBB(NewBB) 80251f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson .addImm(ARMCC::AL).addReg(0); 803fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumSplit; 8048494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 805a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Update the CFG. All succs of OrigBB are now succs of NewBB. 806e80fba0e6c976039c132c3d5d4fcad569d2259a8Jakob Stoklund Olesen NewBB->transferSuccessors(OrigBB); 8078494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 808a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // OrigBB branches to NewBB. 809a8e2989ece6dc46df59b0768184028257f913843Evan Cheng OrigBB->addSuccessor(NewBB); 8108494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 811a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Update internal data structures to account for the newly inserted MBB. 81288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // This is almost the same as UpdateForInsertedWaterBlock, except that 81388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // the Water goes after OrigBB, not NewBB. 8148e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MF.RenumberBlocks(NewBB); 8158494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 816a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen // Insert an entry into BBInfo to align it properly with the (newly 81788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // renumbered) block numbers. 818a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo.insert(BBInfo.begin() + NewBB->getNumber(), BasicBlockInfo()); 81999c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 8208494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // Next, update WaterList. Specifically, we need to add OrigMBB as having 82188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // available water after it (but not if it's already there, which happens 82288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // when splitting before a conditional branch that is followed by an 82388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // unconditional branch - in that case we want to insert NewBB). 824034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson water_iterator IP = 82588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen std::lower_bound(WaterList.begin(), WaterList.end(), OrigBB, 82688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen CompareMBBNumbers); 82788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen MachineBasicBlock* WaterBB = *IP; 82888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (WaterBB == OrigBB) 8297896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner WaterList.insert(llvm::next(IP), NewBB); 83088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen else 83188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen WaterList.insert(IP, OrigBB); 832b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(OrigBB); 83388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 83499c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned OrigBBI = OrigBB->getNumber(); 83599c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned NewBBI = NewBB->getNumber(); 8368494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 83725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng int delta = isThumb1 ? 2 : 4; 8388086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 8398086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // Figure out how large the OrigBB is. As the first half of the original 8408086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // block, it cannot contain a tablejump. The size includes 8418086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // the new jump we added. (It should be possible to do this without 8428086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // recounting everything, but it's very confusing, and this is rarely 8438086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // executed.) 844a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen ComputeBlockSize(OrigBB); 84599c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 84699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // ...and adjust BBOffsets for NewBB accordingly. 8475bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen BBInfo[NewBBI].Offset = BBInfo[OrigBBI].postOffset(); 84899c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 8498086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // Figure out how large the NewMBB is. As the second half of the original 8508086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // block, it may contain a tablejump. 851a26811ec83d00344a739d84f4b8584e5548b94ceJakob Stoklund Olesen ComputeBlockSize(NewBB); 8528086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 8536fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen MachineInstr* ThumbJTMI = prior(NewBB->end()); 8546fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen if (ThumbJTMI->getOpcode() == ARM::tBR_JTr) { 8556fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // We've added another 2-byte instruction before this tablejump, which 8566fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // means we will always need padding if we didn't before, and vice versa. 8576fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen 8586fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // The original offset of the jump instruction was: 8595bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen unsigned OrigOffset = BBInfo[OrigBBI].postOffset() - delta; 8606fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen if (OrigOffset%4 == 0) { 8616fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // We had padding before and now we don't. No net change in code size. 8626fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen delta = 0; 8636fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen } else { 8646fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // We didn't have padding before and now we do. 865a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[NewBBI].Size += 2; 8666fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen delta = 4; 8676fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen } 8686fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen } 8696fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen 87099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // All BBOffsets following these blocks must be modified. 8718086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen if (delta) 8722fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen AdjustBBOffsetsAfter(NewBB); 8730c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng 8740c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng return NewBB; 875a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 876a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 8778593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// OffsetIsInRange - Checks whether UserOffset (the location of a constant pool 8788494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson/// reference) is within MaxDisp of TrialOffset (a proposed location of a 8798593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// constant pool entry). 8808494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilsonbool ARMConstantIslands::OffsetIsInRange(unsigned UserOffset, 881d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng unsigned TrialOffset, unsigned MaxDisp, 882d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool NegativeOK, bool IsSoImm) { 8838494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // On Thumb offsets==2 mod 4 are rounded down by the hardware for 8848494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // purposes of the displacement computation; compensate for that here. 8858593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Effectively, the valid range of displacements is 2 bytes smaller for such 8868593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // references. 88731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned TotalAdj = 0; 88831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb && UserOffset%4 !=0) { 8898593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen UserOffset -= 2; 89031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng TotalAdj = 2; 89131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 8928593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // CPEs will be rounded up to a multiple of 4. 89331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb && TrialOffset%4 != 0) { 8948593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen TrialOffset += 2; 89531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng TotalAdj += 2; 89631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 89731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 89831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // In Thumb2 mode, later branch adjustments can shift instructions up and 89931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // cause alignment change. In the worst case scenario this can cause the 90031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // user's effective address to be subtracted by 2 and the CPE's address to 90131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // be plus 2. 90231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb2 && TotalAdj != 4) 90331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng MaxDisp -= (4 - TotalAdj); 9048593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 90599c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen if (UserOffset <= TrialOffset) { 90699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // User before the Trial. 907d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (TrialOffset - UserOffset <= MaxDisp) 908d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return true; 90940efc251cd7a52dd2375ec95ee38b1be4572178fEvan Cheng // FIXME: Make use full range of soimm values. 91099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen } else if (NegativeOK) { 911d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (UserOffset - TrialOffset <= MaxDisp) 912d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return true; 91340efc251cd7a52dd2375ec95ee38b1be4572178fEvan Cheng // FIXME: Make use full range of soimm values. 91499c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen } 91599c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen return false; 91699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen} 91799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 91888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// WaterIsInRange - Returns true if a CPE placed after the specified 91988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// Water (a basic block) will be in range for the specific MI. 92088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 92188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesenbool ARMConstantIslands::WaterIsInRange(unsigned UserOffset, 9225d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng MachineBasicBlock* Water, CPUser &U) { 9235d9c4b60204d741c213456e21b87e9af6a3dc627Dale Johannesen unsigned MaxDisp = U.MaxDisp; 9245bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen unsigned CPEOffset = BBInfo[Water->getNumber()].postOffset(); 92588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 926d959aa421a8d14fc5aad29141f816db8f4362c7fDale Johannesen // If the CPE is to be inserted before the instruction, that will raise 927af4b7352193e4a024d4a4e87cac1ba1589e4de57Bob Wilson // the offset of the instruction. 928d959aa421a8d14fc5aad29141f816db8f4362c7fDale Johannesen if (CPEOffset < UserOffset) 9295d9c4b60204d741c213456e21b87e9af6a3dc627Dale Johannesen UserOffset += U.CPEMI->getOperand(2).getImm(); 930d959aa421a8d14fc5aad29141f816db8f4362c7fDale Johannesen 931d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return OffsetIsInRange(UserOffset, CPEOffset, MaxDisp, U.NegOk, U.IsSoImm); 93288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen} 93388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 93488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// CPEIsInRange - Returns true if the distance between specific MI and 935c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng/// specific ConstPool entry instruction can fit in MI's displacement field. 93688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesenbool ARMConstantIslands::CPEIsInRange(MachineInstr *MI, unsigned UserOffset, 9375d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng MachineInstr *CPEMI, unsigned MaxDisp, 9385d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool NegOk, bool DoDump) { 9398593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen unsigned CPEOffset = GetOffsetOf(CPEMI); 9404d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach assert((CPEOffset%4 == 0 || HasInlineAsm) && "Misaligned CPE"); 9412021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng 94288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (DoDump) { 943705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << "User of CPE#" << CPEMI->getOperand(0).getImm() 944705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " max delta=" << MaxDisp 945705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " insn address=" << UserOffset 946705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " CPE address=" << CPEOffset 947705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " offset=" << int(CPEOffset-UserOffset) << "\t" << *MI); 94888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 949a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 9505d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng return OffsetIsInRange(UserOffset, CPEOffset, MaxDisp, NegOk); 951c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng} 952c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng 953d1e7d9a88b5f4fa5e9a85affc4599c650c591ffbEvan Cheng#ifndef NDEBUG 954c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// BBIsJumpedOver - Return true of the specified basic block's only predecessor 955c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// unconditionally branches to its only successor. 956c99ef085b90b32952b484e8843fb66ad65215b61Evan Chengstatic bool BBIsJumpedOver(MachineBasicBlock *MBB) { 957c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng if (MBB->pred_size() != 1 || MBB->succ_size() != 1) 958c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return false; 959c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 960c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineBasicBlock *Succ = *MBB->succ_begin(); 961c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineBasicBlock *Pred = *MBB->pred_begin(); 962c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineInstr *PredMI = &Pred->back(); 9635e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin if (PredMI->getOpcode() == ARM::B || PredMI->getOpcode() == ARM::tB 9645e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin || PredMI->getOpcode() == ARM::t2B) 965c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return PredMI->getOperand(0).getMBB() == Succ; 966c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return false; 967c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng} 968d1e7d9a88b5f4fa5e9a85affc4599c650c591ffbEvan Cheng#endif // NDEBUG 969c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 9702fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesenvoid ARMConstantIslands::AdjustBBOffsetsAfter(MachineBasicBlock *BB) { 9717896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineFunction::iterator MBBI = BB; MBBI = llvm::next(MBBI); 972d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng for(unsigned i = BB->getNumber()+1, e = BB->getParent()->getNumBlockIDs(); 973d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng i < e; ++i) { 9742fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen unsigned OldOffset = BBInfo[i].Offset; 9752fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen BBInfo[i].Offset = BBInfo[i-1].postOffset(); 9762fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen int delta = BBInfo[i].Offset - OldOffset; 9778593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // If some existing blocks have padding, adjust the padding as needed, a 9788593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // bit tricky. delta can be negative so don't use % on that. 979d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (!isThumb) 980d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng continue; 981d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MachineBasicBlock *MBB = MBBI; 9824d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach if (!MBB->empty() && !HasInlineAsm) { 983d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // Constant pool entries require padding. 984d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (MBB->begin()->getOpcode() == ARM::CONSTPOOL_ENTRY) { 985a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen if ((OldOffset%4) == 0 && (BBInfo[i].Offset%4) != 0) { 986d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // add new padding 987a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[i].Size += 2; 988d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta += 2; 989a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen } else if ((OldOffset%4) != 0 && (BBInfo[i].Offset%4) == 0) { 990d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // remove existing padding 991a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[i].Size -= 2; 992d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta -= 2; 9938593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 994d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng } 995d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // Thumb1 jump tables require padding. They should be at the end; 996d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // following unconditional branches are removed by AnalyzeBranch. 997b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng // tBR_JTr expands to a mov pc followed by .align 2 and then the jump 9988086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // table entries. So this code checks whether offset of tBR_JTr 9998086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // is aligned; if it is, the offset of the jump table following the 10008086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // instruction will not be aligned, and we need padding. 1001789476240d6b6f8ad9366cadf790a82bd41bb0b3Evan Cheng MachineInstr *ThumbJTMI = prior(MBB->end()); 100266ac53165e17b7c76b8c69e57bde623d44ec492eEvan Cheng if (ThumbJTMI->getOpcode() == ARM::tBR_JTr) { 10038086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen unsigned NewMIOffset = GetOffsetOf(ThumbJTMI); 10044a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng unsigned OldMIOffset = NewMIOffset - delta; 10054a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng if ((OldMIOffset%4) == 0 && (NewMIOffset%4) != 0) { 1006d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // remove existing padding 1007a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[i].Size -= 2; 10084a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng } else if ((OldMIOffset%4) != 0 && (NewMIOffset%4) == 0) { 1009d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // add new padding 1010a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[i].Size += 2; 10118593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 10128593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 10138593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 10147896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MBBI = llvm::next(MBBI); 10158593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 101699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen} 101799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 101888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// DecrementOldEntry - find the constant pool entry with index CPI 101988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// and instruction CPEMI, and decrement its refcount. If the refcount 10208494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson/// becomes 0 remove the entry and instruction. Returns true if we removed 102188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// the entry, false if we didn't. 1022b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng 1023ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Chengbool ARMConstantIslands::DecrementOldEntry(unsigned CPI, MachineInstr *CPEMI) { 1024c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Find the old entry. Eliminate it if it is no longer used. 1025ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng CPEntry *CPE = findConstPoolEntry(CPI, CPEMI); 1026ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng assert(CPE && "Unexpected!"); 1027ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (--CPE->RefCount == 0) { 1028ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng RemoveDeadCPEMI(CPEMI); 1029ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng CPE->CPEMI = NULL; 1030fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman --NumCPEs; 103188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return true; 103288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 103388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return false; 103488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen} 103588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 103688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// LookForCPEntryInRange - see if the currently referenced CPE is in range; 103788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// if not, see if an in-range clone of the CPE is in range, and if so, 103888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// change the data structures so the user references the clone. Returns: 103988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// 0 = no existing entry found 104088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// 1 = entry found, and there were no code insertions or deletions 104188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// 2 = entry found, and there were code insertions or deletions 104288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesenint ARMConstantIslands::LookForExistingCPEntry(CPUser& U, unsigned UserOffset) 104388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen{ 104488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen MachineInstr *UserMI = U.MI; 104588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen MachineInstr *CPEMI = U.CPEMI; 104688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 104788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Check to see if the CPE is already in-range. 10485d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng if (CPEIsInRange(UserMI, UserOffset, CPEMI, U.MaxDisp, U.NegOk, true)) { 1049893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "In range\n"); 105088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return 1; 1051c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng } 1052c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 105388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // No. Look for previously created clones of the CPE that are in range. 10548aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner unsigned CPI = CPEMI->getOperand(1).getIndex(); 105588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen std::vector<CPEntry> &CPEs = CPEntries[CPI]; 105688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen for (unsigned i = 0, e = CPEs.size(); i != e; ++i) { 105788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // We already tried this one 105888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (CPEs[i].CPEMI == CPEMI) 105988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen continue; 106088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Removing CPEs can leave empty entries, skip 106188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (CPEs[i].CPEMI == NULL) 106288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen continue; 10635d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng if (CPEIsInRange(UserMI, UserOffset, CPEs[i].CPEMI, U.MaxDisp, U.NegOk)) { 1064893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Replacing CPE#" << CPI << " with CPE#" 1065893e1c90a03a53cf13f73849324e83612688428aChris Lattner << CPEs[i].CPI << "\n"); 106688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Point the CPUser node to the replacement 106788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen U.CPEMI = CPEs[i].CPEMI; 106888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Change the CPI in the instruction operand to refer to the clone. 106988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen for (unsigned j = 0, e = UserMI->getNumOperands(); j != e; ++j) 1070d735b8019b0f297d7c14b55adcd887af24d8e602Dan Gohman if (UserMI->getOperand(j).isCPI()) { 10718aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner UserMI->getOperand(j).setIndex(CPEs[i].CPI); 107288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen break; 107388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 107488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Adjust the refcount of the clone... 107588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen CPEs[i].RefCount++; 107688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // ...and the original. If we didn't remove the old entry, none of the 107788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // addresses changed, so we don't need another pass. 1078ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng return DecrementOldEntry(CPI, CPEMI) ? 2 : 1; 107988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 108088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 108188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return 0; 108288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen} 108388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 1084f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen/// getUnconditionalBrDisp - Returns the maximum displacement that can fit in 1085f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen/// the specific unconditional branch instruction. 1086f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesenstatic inline unsigned getUnconditionalBrDisp(int Opc) { 10875e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin switch (Opc) { 10885e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::tB: 10895e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin return ((1<<10)-1)*2; 10905e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::t2B: 10915e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin return ((1<<23)-1)*2; 10925e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin default: 10935e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin break; 10945e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin } 1095764ab52dd80310a205c9888bf166d09dab858f90Jim Grosbach 10965e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin return ((1<<23)-1)*4; 1097f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen} 1098f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen 1099b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson/// LookForWater - Look for an existing entry in the WaterList in which 1100b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// we can place the CPE referenced from U so it's within range of U's MI. 1101b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson/// Returns true if found, false if not. If it returns true, WaterIter 1102f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// is set to the WaterList entry. For Thumb, prefer water that will not 1103f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// introduce padding to water that will. To ensure that this pass 1104f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// terminates, the CPE location for a particular CPUser is only allowed to 1105f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// move to a lower address, so search backward from the end of the list and 1106f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// prefer the first water that is in range. 1107b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesenbool ARMConstantIslands::LookForWater(CPUser &U, unsigned UserOffset, 1108b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson water_iterator &WaterIter) { 11093b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson if (WaterList.empty()) 11103b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson return false; 11113b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson 111232c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson bool FoundWaterThatWouldPad = false; 111332c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson water_iterator IPThatWouldPad; 11143b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson for (water_iterator IP = prior(WaterList.end()), 11153b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson B = WaterList.begin();; --IP) { 11163b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson MachineBasicBlock* WaterBB = *IP; 1117b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Check if water is in range and is either at a lower address than the 1118b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // current "high water mark" or a new water block that was created since 1119b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // the previous iteration by inserting an unconditional branch. In the 1120b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // latter case, we want to allow resetting the high water mark back to 1121b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // this new water since we haven't seen it before. Inserting branches 1122b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // should be relatively uncommon and when it does happen, we want to be 1123b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // sure to take advantage of it for all the CPEs near that block, so that 1124b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // we don't insert more branches than necessary. 1125b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (WaterIsInRange(UserOffset, WaterBB, U) && 1126b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson (WaterBB->getNumber() < U.HighWaterMark->getNumber() || 1127b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.count(WaterBB))) { 11283b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson unsigned WBBId = WaterBB->getNumber(); 11295bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen if (isThumb && BBInfo[WBBId].postOffset()%4 != 0) { 11303b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson // This is valid Water, but would introduce padding. Remember 11313b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson // it in case we don't find any Water that doesn't do this. 113232c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson if (!FoundWaterThatWouldPad) { 113332c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson FoundWaterThatWouldPad = true; 11343b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson IPThatWouldPad = IP; 1135f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 11363b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson } else { 1137b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterIter = IP; 11383b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson return true; 1139d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng } 114088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 11413b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson if (IP == B) 11423b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson break; 114388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 114432c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson if (FoundWaterThatWouldPad) { 1145b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterIter = IPThatWouldPad; 11468593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 11478593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 1148b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen return false; 1149b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen} 115088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 11518494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson/// CreateNewWater - No existing WaterList entry will work for 1152b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// CPUsers[CPUserIndex], so create a place to put the CPE. The end of the 1153b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// block is used if in range, and the conditional branch munged so control 1154b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// flow is correct. Otherwise the block is split to create a hole with an 1155757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson/// unconditional branch around it. In either case NewMBB is set to a 1156b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// block following which the new island can be inserted (the WaterList 1157b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// is not adjusted). 11588494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilsonvoid ARMConstantIslands::CreateNewWater(unsigned CPUserIndex, 1159757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson unsigned UserOffset, 1160757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson MachineBasicBlock *&NewMBB) { 1161b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUser &U = CPUsers[CPUserIndex]; 1162b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *UserMI = U.MI; 1163b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *CPEMI = U.CPEMI; 1164b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineBasicBlock *UserMBB = UserMI->getParent(); 11655bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen unsigned OffsetOfNextBlock = BBInfo[UserMBB->getNumber()].postOffset(); 11665bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen assert(OffsetOfNextBlock == BBInfo[UserMBB->getNumber()+1].Offset); 1167b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 116836fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // If the block does not end in an unconditional branch already, and if the 116936fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // end of the block is within range, make new water there. (The addition 117036fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // below is for the unconditional branch we will be adding: 4 bytes on ARM + 117136fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // Thumb2, 2 on Thumb1. Possible Thumb1 alignment padding is allowed for 11728593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // inside OffsetIsInRange. 117336fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson if (BBHasFallthrough(UserMBB) && 1174d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng OffsetIsInRange(UserOffset, OffsetOfNextBlock + (isThumb1 ? 2: 4), 1175d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng U.MaxDisp, U.NegOk, U.IsSoImm)) { 1176893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Split at end of block\n"); 1177b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (&UserMBB->back() == UserMI) 1178b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen assert(BBHasFallthrough(UserMBB) && "Expected a fallthrough BB!"); 11797896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner NewMBB = llvm::next(MachineFunction::iterator(UserMBB)); 1180b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // Add an unconditional branch from UserMBB to fallthrough block. 1181b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // Record it for branch lengthening; this new branch will not get out of 1182b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // range, but if the preceding conditional branch is out of range, the 1183b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // targets will be exchanged, and the altered branch may be out of 1184b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // range, so the machinery has to know about it. 11855e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin int UncondBr = isThumb ? ((isThumb2) ? ARM::t2B : ARM::tB) : ARM::B; 118651f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson if (!isThumb) 118751f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(UserMBB, DebugLoc(), TII->get(UncondBr)).addMBB(NewMBB); 118851f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson else 118951f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(UserMBB, DebugLoc(), TII->get(UncondBr)).addMBB(NewMBB) 119051f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson .addImm(ARMCC::AL).addReg(0); 1191b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned MaxDisp = getUnconditionalBrDisp(UncondBr); 11928494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson ImmBranches.push_back(ImmBranch(&UserMBB->back(), 1193b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MaxDisp, false, UncondBr)); 1194d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng int delta = isThumb1 ? 2 : 4; 1195a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[UserMBB->getNumber()].Size += delta; 11962fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen AdjustBBOffsetsAfter(UserMBB); 1197b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen } else { 1198b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // What a big block. Find a place within the block to split it. 1199d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // This is a little tricky on Thumb1 since instructions are 2 bytes 1200b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // and constant pool entries are 4 bytes: if instruction I references 1201b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // island CPE, and instruction I+1 references CPE', it will 1202b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // not work well to put CPE as far forward as possible, since then 1203b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // CPE' cannot immediately follow it (that location is 2 bytes 1204b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // farther away from I+1 than CPE was from I) and we'd need to create 12058593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // a new island. So, we make a first guess, then walk through the 12068593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // instructions between the one currently being looked at and the 12078593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // possible insertion point, and make sure any other instructions 12088593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // that reference CPEs will be able to use the same island area; 12098593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // if not, we back up the insertion point. 12108593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 1211b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // The 4 in the following is for the unconditional branch we'll be 1212d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // inserting (allows for long branch on Thumb1). Alignment of the 12138593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // island is handled inside OffsetIsInRange. 12148593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen unsigned BaseInsertOffset = UserOffset + U.MaxDisp -4; 1215b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // This could point off the end of the block if we've already got 1216b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // constant pool entries following this block; only the last one is 1217b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // in the water list. Back past any possible branches (allow for a 1218b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // conditional and a maximally long unconditional). 1219a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen if (BaseInsertOffset >= BBInfo[UserMBB->getNumber()+1].Offset) 1220a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BaseInsertOffset = BBInfo[UserMBB->getNumber()+1].Offset - 1221d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng (isThumb1 ? 6 : 8); 1222b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned EndInsertOffset = BaseInsertOffset + 1223b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPEMI->getOperand(2).getImm(); 1224b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineBasicBlock::iterator MI = UserMI; 1225b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen ++MI; 1226b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned CPUIndex = CPUserIndex+1; 1227719510a178a910feb1db707140011c32a30992c4Evan Cheng unsigned NumCPUsers = CPUsers.size(); 1228719510a178a910feb1db707140011c32a30992c4Evan Cheng MachineInstr *LastIT = 0; 122952e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray for (unsigned Offset = UserOffset+TII->GetInstSizeInBytes(UserMI); 1230b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen Offset < BaseInsertOffset; 123152e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray Offset += TII->GetInstSizeInBytes(MI), 1232719510a178a910feb1db707140011c32a30992c4Evan Cheng MI = llvm::next(MI)) { 1233719510a178a910feb1db707140011c32a30992c4Evan Cheng if (CPUIndex < NumCPUsers && CPUsers[CPUIndex].MI == MI) { 1234d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng CPUser &U = CPUsers[CPUIndex]; 12358494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson if (!OffsetIsInRange(Offset, EndInsertOffset, 1236d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng U.MaxDisp, U.NegOk, U.IsSoImm)) { 1237d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng BaseInsertOffset -= (isThumb1 ? 2 : 4); 1238d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng EndInsertOffset -= (isThumb1 ? 2 : 4); 1239f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 1240b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // This is overly conservative, as we don't account for CPEMIs 1241b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // being reused within the block, but it doesn't matter much. 1242b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen EndInsertOffset += CPUsers[CPUIndex].CPEMI->getOperand(2).getImm(); 1243b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUIndex++; 1244f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 1245719510a178a910feb1db707140011c32a30992c4Evan Cheng 1246719510a178a910feb1db707140011c32a30992c4Evan Cheng // Remember the last IT instruction. 1247719510a178a910feb1db707140011c32a30992c4Evan Cheng if (MI->getOpcode() == ARM::t2IT) 1248719510a178a910feb1db707140011c32a30992c4Evan Cheng LastIT = MI; 124988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 1250719510a178a910feb1db707140011c32a30992c4Evan Cheng 1251893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Split in middle of big block\n"); 1252719510a178a910feb1db707140011c32a30992c4Evan Cheng --MI; 1253719510a178a910feb1db707140011c32a30992c4Evan Cheng 1254719510a178a910feb1db707140011c32a30992c4Evan Cheng // Avoid splitting an IT block. 1255719510a178a910feb1db707140011c32a30992c4Evan Cheng if (LastIT) { 1256719510a178a910feb1db707140011c32a30992c4Evan Cheng unsigned PredReg = 0; 1257719510a178a910feb1db707140011c32a30992c4Evan Cheng ARMCC::CondCodes CC = llvm::getITInstrPredicate(MI, PredReg); 1258719510a178a910feb1db707140011c32a30992c4Evan Cheng if (CC != ARMCC::AL) 1259719510a178a910feb1db707140011c32a30992c4Evan Cheng MI = LastIT; 1260719510a178a910feb1db707140011c32a30992c4Evan Cheng } 1261719510a178a910feb1db707140011c32a30992c4Evan Cheng NewMBB = SplitBlockBeforeInstr(MI); 1262b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen } 1263b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen} 1264b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1265b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// HandleConstantPoolUser - Analyze the specified user, checking to see if it 126639bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson/// is out-of-range. If so, pick up the constant pool value and move it some 1267b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// place in-range. Return true if we changed any addresses (thus must run 1268b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// another pass of branch lengthening), false otherwise. 12695657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::HandleConstantPoolUser(MachineFunction &MF, 12708494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson unsigned CPUserIndex) { 1271b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUser &U = CPUsers[CPUserIndex]; 1272b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *UserMI = U.MI; 1273b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *CPEMI = U.CPEMI; 12748aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner unsigned CPI = CPEMI->getOperand(1).getIndex(); 1275b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned Size = CPEMI->getOperand(2).getImm(); 12768593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Compute this only once, it's expensive. The 4 or 8 is the value the 1277a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // hardware keeps in the PC. 1278b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned UserOffset = GetOffsetOf(UserMI) + (isThumb ? 4 : 8); 1279768c9f725bda048b3406b6289beb586ff6e933dfEvan Cheng 1280b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // See if the current entry is within range, or there is a clone of it 1281b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // in range. 1282b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen int result = LookForExistingCPEntry(U, UserOffset); 1283b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (result==1) return false; 1284b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen else if (result==2) return true; 1285b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1286b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // No existing clone of this CPE is within range. 1287b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // We will be generating a new clone. Get a UID for it. 12885de5d4b6d0eb3fd379fa571d82f6fa764460b3b8Evan Cheng unsigned ID = AFI->createPICLabelUId(); 1289b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1290f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson // Look for water where we can place this CPE. 1291b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *NewIsland = MF.CreateMachineBasicBlock(); 1292b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *NewMBB; 1293b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson water_iterator IP; 1294b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (LookForWater(U, UserOffset, IP)) { 1295b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson DEBUG(errs() << "found water in range\n"); 1296b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *WaterBB = *IP; 1297b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1298b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // If the original WaterList entry was "new water" on this iteration, 1299b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // propagate that to the new island. This is just keeping NewWaterList 1300b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // updated to match the WaterList, which will be updated below. 1301b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (NewWaterList.count(WaterBB)) { 1302b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.erase(WaterBB); 1303b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(NewIsland); 1304b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson } 1305b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // The new CPE goes before the following block (NewMBB). 13067896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner NewMBB = llvm::next(MachineFunction::iterator(WaterBB)); 1307b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1308b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson } else { 1309b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // No water found. 1310893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "No water found\n"); 1311757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson CreateNewWater(CPUserIndex, UserOffset, NewMBB); 1312b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1313b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // SplitBlockBeforeInstr adds to WaterList, which is important when it is 1314b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // called while handling branches so that the water will be seen on the 1315b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // next iteration for constant pools, but in this context, we don't want 1316b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // it. Check for this so it will be removed from the WaterList. 1317b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Also remove any entry from NewWaterList. 1318b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *WaterBB = prior(MachineFunction::iterator(NewMBB)); 1319b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson IP = std::find(WaterList.begin(), WaterList.end(), WaterBB); 1320b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (IP != WaterList.end()) 1321b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.erase(WaterBB); 1322b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1323b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // We are adding new water. Update NewWaterList. 1324b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(NewIsland); 132588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 132688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 1327b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Remove the original WaterList entry; we want subsequent insertions in 1328b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // this vicinity to go after the one we're about to insert. This 1329b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // considerably reduces the number of times we have to move the same CPE 1330b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // more than once and is also important to ensure the algorithm terminates. 1331b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (IP != WaterList.end()) 1332b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterList.erase(IP); 1333b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 133488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Okay, we know we can put an island before NewMBB now, do it! 13355657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.insert(NewMBB, NewIsland); 133688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 133788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Update internal data structures to account for the newly inserted MBB. 133888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen UpdateForInsertedWaterBlock(NewIsland); 133988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 134088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Decrement the old entry, and remove it if refcount becomes 0. 1341ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng DecrementOldEntry(CPI, CPEMI); 134288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 134388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Now that we have an island to add the CPE to, clone the original CPE and 134488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // add it to the island. 1345549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson U.HighWaterMark = NewIsland; 1346c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner U.CPEMI = BuildMI(NewIsland, DebugLoc(), TII->get(ARM::CONSTPOOL_ENTRY)) 1347a8e2989ece6dc46df59b0768184028257f913843Evan Cheng .addImm(ID).addConstantPoolIndex(CPI).addImm(Size); 134888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen CPEntries[CPI].push_back(CPEntry(U.CPEMI, ID, 1)); 1349fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCPEs; 1350c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 13513e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen // Mark the basic block as 4-byte aligned as required by the const-pool entry. 13523e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen NewIsland->setAlignment(2); 13533e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen 1354a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[NewIsland->getNumber()].Offset = BBInfo[NewMBB->getNumber()].Offset; 1355b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng // Compensate for .align 2 in thumb mode. 1356a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen if (isThumb && (BBInfo[NewIsland->getNumber()].Offset%4 != 0 || HasInlineAsm)) 13578593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen Size += 2; 1358a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Increase the size of the island block to account for the new entry. 1359a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[NewIsland->getNumber()].Size += Size; 13602fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen AdjustBBOffsetsAfter(NewIsland); 13618494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1362a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Finally, change the CPI in the instruction operand to be ID. 1363a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned i = 0, e = UserMI->getNumOperands(); i != e; ++i) 1364d735b8019b0f297d7c14b55adcd887af24d8e602Dan Gohman if (UserMI->getOperand(i).isCPI()) { 13658aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner UserMI->getOperand(i).setIndex(ID); 1366a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 1367a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 13688494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1369705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Moved CPE to #" << ID << " CPI=" << CPI 1370705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << '\t' << *UserMI); 13718494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1372a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return true; 1373a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 1374a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 1375ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// RemoveDeadCPEMI - Remove a dead constant pool entry instruction. Update 1376ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// sizes and offsets of impacted basic blocks. 1377ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Chengvoid ARMConstantIslands::RemoveDeadCPEMI(MachineInstr *CPEMI) { 1378ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng MachineBasicBlock *CPEBB = CPEMI->getParent(); 13798593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen unsigned Size = CPEMI->getOperand(2).getImm(); 13808593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen CPEMI->eraseFromParent(); 1381a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[CPEBB->getNumber()].Size -= Size; 13828593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // All succeeding offsets have the current size value added in, fix this. 1383ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (CPEBB->empty()) { 1384d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // In thumb1 mode, the size of island may be padded by two to compensate for 13858593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // the alignment requirement. Then it will now be 2 when the block is 1386ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng // empty, so fix this. 1387ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng // All succeeding offsets have the current size value added in, fix this. 1388a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen if (BBInfo[CPEBB->getNumber()].Size != 0) { 1389a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen Size += BBInfo[CPEBB->getNumber()].Size; 1390a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[CPEBB->getNumber()].Size = 0; 1391ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 1392305e5fe797cbba32d8091d687d47e98c8f3ee1f4Jakob Stoklund Olesen 1393305e5fe797cbba32d8091d687d47e98c8f3ee1f4Jakob Stoklund Olesen // This block no longer needs to be aligned. <rdar://problem/10534709>. 1394305e5fe797cbba32d8091d687d47e98c8f3ee1f4Jakob Stoklund Olesen CPEBB->setAlignment(0); 1395ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 13962fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen AdjustBBOffsetsAfter(CPEBB); 13978593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // An island has only one predecessor BB and one successor BB. Check if 13988593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // this BB's predecessor jumps directly to this BB's successor. This 13998593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // shouldn't happen currently. 14008593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen assert(!BBIsJumpedOver(CPEBB) && "How did this happen?"); 14018593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // FIXME: remove the empty blocks after all the work is done? 1402ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng} 1403ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 1404ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// RemoveUnusedCPEntries - Remove constant pool entries whose refcounts 1405ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// are zero. 1406ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Chengbool ARMConstantIslands::RemoveUnusedCPEntries() { 1407ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng unsigned MadeChange = false; 1408ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng for (unsigned i = 0, e = CPEntries.size(); i != e; ++i) { 1409ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng std::vector<CPEntry> &CPEs = CPEntries[i]; 1410ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng for (unsigned j = 0, ee = CPEs.size(); j != ee; ++j) { 1411ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (CPEs[j].RefCount == 0 && CPEs[j].CPEMI) { 1412ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng RemoveDeadCPEMI(CPEs[j].CPEMI); 1413ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng CPEs[j].CPEMI = NULL; 1414ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng MadeChange = true; 1415ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 1416ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 14178494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson } 1418ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng return MadeChange; 1419ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng} 1420ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 142188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// BBIsInRange - Returns true if the distance between specific MI and 142243aeab68a69e443c528092b4424a498d813f96b7Evan Cheng/// specific BB can fit in MI's displacement field. 1423c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Chengbool ARMConstantIslands::BBIsInRange(MachineInstr *MI,MachineBasicBlock *DestBB, 1424c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng unsigned MaxDisp) { 1425b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned PCAdj = isThumb ? 4 : 8; 1426c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng unsigned BrOffset = GetOffsetOf(MI) + PCAdj; 1427a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen unsigned DestOffset = BBInfo[DestBB->getNumber()].Offset; 142843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1429705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << "Branch of destination BB#" << DestBB->getNumber() 1430705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " from BB#" << MI->getParent()->getNumber() 1431705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " max delta=" << MaxDisp 1432705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " from " << GetOffsetOf(MI) << " to " << DestOffset 1433705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " offset " << int(DestOffset-BrOffset) << "\t" << *MI); 1434c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng 14358593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (BrOffset <= DestOffset) { 14368593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Branch before the Dest. 14378593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (DestOffset-BrOffset <= MaxDisp) 14388593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 14398593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } else { 14408593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (BrOffset-DestOffset <= MaxDisp) 14418593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 14428593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 14438593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return false; 144443aeab68a69e443c528092b4424a498d813f96b7Evan Cheng} 144543aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1446d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// FixUpImmediateBr - Fix up an immediate branch whose destination is too far 1447d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// away to fit in its displacement field. 14485657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::FixUpImmediateBr(MachineFunction &MF, ImmBranch &Br) { 1449d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = Br.MI; 14508aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *DestBB = MI->getOperand(0).getMBB(); 1451d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1452c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng // Check to see if the DestBB is already in-range. 1453c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng if (BBIsInRange(MI, DestBB, Br.MaxDisp)) 1454d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return false; 1455d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1456d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng if (!Br.isCond) 14575657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return FixUpUnconditionalBr(MF, Br); 14585657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return FixUpConditionalBr(MF, Br); 1459d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 1460d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 146188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// FixUpUnconditionalBr - Fix up an unconditional branch whose destination is 146288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// too far away to fit in its displacement field. If the LR register has been 1463d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// spilled in the epilogue, then we can use BL to implement a far jump. 146439bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson/// Otherwise, add an intermediate branch instruction to a branch. 1465d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Chengbool 14665657c01949dca6c012ac60d242d1a8d2ffdf5603Evan ChengARMConstantIslands::FixUpUnconditionalBr(MachineFunction &MF, ImmBranch &Br) { 1467d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = Br.MI; 1468d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineBasicBlock *MBB = MI->getParent(); 146953c67c0218d8420234dd71bf2d9df3388909af77Evan Cheng if (!isThumb1) 147053c67c0218d8420234dd71bf2d9df3388909af77Evan Cheng llvm_unreachable("FixUpUnconditionalBr is Thumb1 only!"); 1471d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1472d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // Use BL to implement far jump. 1473d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng Br.MaxDisp = (1 << 21) * 2; 14745080f4d9919d39b367891dc51e739c571a66036cChris Lattner MI->setDesc(TII->get(ARM::tBfar)); 1475a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size += 2; 14762fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen AdjustBBOffsetsAfter(MBB); 1477d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng HasFarJump = true; 1478fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumUBrFixed; 1479bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng 1480705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Changed B to long jump " << *MI); 1481bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng 1482d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return true; 1483d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 1484d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 148588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// FixUpConditionalBr - Fix up a conditional branch whose destination is too 1486d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// far away to fit in its displacement field. It is converted to an inverse 1487d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// conditional branch + an unconditional branch to the destination. 1488af5cbcb809bdbd30ebacab942994721c134d16a2Evan Chengbool 14895657c01949dca6c012ac60d242d1a8d2ffdf5603Evan ChengARMConstantIslands::FixUpConditionalBr(MachineFunction &MF, ImmBranch &Br) { 1490af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MachineInstr *MI = Br.MI; 14918aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *DestBB = MI->getOperand(0).getMBB(); 1492af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 149339bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // Add an unconditional branch to the destination and invert the branch 1494d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // condition to jump over it: 1495af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // blt L1 1496af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // => 1497af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // bge L2 1498af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // b L1 1499af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // L2: 15009a1ceaedc282f0cae31f2723f4d6c00c7b88fe90Chris Lattner ARMCC::CondCodes CC = (ARMCC::CondCodes)MI->getOperand(1).getImm(); 1501af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng CC = ARMCC::getOppositeCondition(CC); 15020e1d37904abbf7e8c4c478408253dd995f3040f4Evan Cheng unsigned CCReg = MI->getOperand(2).getReg(); 1503af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 1504af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // If the branch is at the end of its MBB and that has a fall-through block, 1505af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // direct the updated conditional branch to the fall-through block. Otherwise, 1506af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // split the MBB before the next instruction. 1507af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 1508bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng MachineInstr *BMI = &MBB->back(); 1509bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng bool NeedSplit = (BMI != MI) || !BBHasFallthrough(MBB); 151043aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1511fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCBrFixed; 1512bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng if (BMI != MI) { 15137896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner if (llvm::next(MachineBasicBlock::iterator(MI)) == prior(MBB->end()) && 1514bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng BMI->getOpcode() == Br.UncondBr) { 151539bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // Last MI in the BB is an unconditional branch. Can we simply invert the 151643aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // condition and swap destinations: 151743aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // beq L1 151843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // b L2 151943aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // => 152043aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // bne L2 152143aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // b L1 15228aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *NewDest = BMI->getOperand(0).getMBB(); 1523c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng if (BBIsInRange(MI, NewDest, Br.MaxDisp)) { 1524705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Invert Bcc condition and swap its destination with " 1525705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << *BMI); 15268aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner BMI->getOperand(0).setMBB(DestBB); 15278aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MI->getOperand(0).setMBB(NewDest); 152843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng MI->getOperand(1).setImm(CC); 152943aeab68a69e443c528092b4424a498d813f96b7Evan Cheng return true; 153043aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 153143aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 153243aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 153343aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 153443aeab68a69e443c528092b4424a498d813f96b7Evan Cheng if (NeedSplit) { 1535af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng SplitBlockBeforeInstr(MI); 153639bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // No need for the branch to the next block. We're adding an unconditional 1537dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng // branch to the destination. 153852e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray int delta = TII->GetInstSizeInBytes(&MBB->back()); 1539a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size -= delta; 1540dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng MBB->back().eraseFromParent(); 1541a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen // BBInfo[SplitBB].Offset is wrong temporarily, fixed below 1542dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng } 15437896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineBasicBlock *NextBB = llvm::next(MachineFunction::iterator(MBB)); 15448494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1545893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << " Insert B to BB#" << DestBB->getNumber() 1546893e1c90a03a53cf13f73849324e83612688428aChris Lattner << " also invert condition and change dest. to BB#" 1547893e1c90a03a53cf13f73849324e83612688428aChris Lattner << NextBB->getNumber() << "\n"); 1548af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 154956c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen // Insert a new conditional branch and a new unconditional branch. 1550af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // Also update the ImmBranch as well as adding a new entry for the new branch. 1551c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(MBB, DebugLoc(), TII->get(MI->getOpcode())) 1552b67284057ee130114055309eabe0bcd1af13777dDale Johannesen .addMBB(NextBB).addImm(CC).addReg(CCReg); 1553af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Br.MI = &MBB->back(); 1554a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size += TII->GetInstSizeInBytes(&MBB->back()); 1555cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson if (isThumb) 1556cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson BuildMI(MBB, DebugLoc(), TII->get(Br.UncondBr)).addMBB(DestBB) 1557cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson .addImm(ARMCC::AL).addReg(0); 1558cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson else 1559cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson BuildMI(MBB, DebugLoc(), TII->get(Br.UncondBr)).addMBB(DestBB); 1560a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size += TII->GetInstSizeInBytes(&MBB->back()); 1561a9b8b8d62c67e96bc4dc2ed25298c539102f8638Evan Cheng unsigned MaxDisp = getUnconditionalBrDisp(Br.UncondBr); 1562a0bf794eb60b6795a121efcb9ff759e9e0955772Evan Cheng ImmBranches.push_back(ImmBranch(&MBB->back(), MaxDisp, false, Br.UncondBr)); 156356c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen 156456c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen // Remove the old conditional branch. It may or may not still be in MBB. 1565a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MI->getParent()->getNumber()].Size -= TII->GetInstSizeInBytes(MI); 1566af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MI->eraseFromParent(); 15672fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen AdjustBBOffsetsAfter(MBB); 1568af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng return true; 1569af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng} 1570d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1571d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// UndoLRSpillRestore - Remove Thumb push / pop instructions that only spills 15724b322e58b77d16f103d88a3af3a4ebd2675245a0Evan Cheng/// LR / restores LR to pc. FIXME: This is done here because it's only possible 15734b322e58b77d16f103d88a3af3a4ebd2675245a0Evan Cheng/// to do this if tBfar is not used. 1574d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Chengbool ARMConstantIslands::UndoLRSpillRestore() { 1575d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng bool MadeChange = false; 1576d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng for (unsigned i = 0, e = PushPopMIs.size(); i != e; ++i) { 1577d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = PushPopMIs[i]; 1578815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson // First two operands are predicates. 157944bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng if (MI->getOpcode() == ARM::tPOP_RET && 1580815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson MI->getOperand(2).getReg() == ARM::PC && 1581815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson MI->getNumExplicitOperands() == 3) { 158225e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach // Create the new insn and copy the predicate from the old. 158325e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach BuildMI(MI->getParent(), MI->getDebugLoc(), TII->get(ARM::tBX_RET)) 158425e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach .addOperand(MI->getOperand(0)) 158525e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach .addOperand(MI->getOperand(1)); 158644bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng MI->eraseFromParent(); 158744bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng MadeChange = true; 1588d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng } 1589d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng } 1590d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return MadeChange; 1591d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 15925657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 1593a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Chengbool ARMConstantIslands::OptimizeThumb2Instructions(MachineFunction &MF) { 1594a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng bool MadeChange = false; 1595a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1596a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // Shrink ADR and LDR from constantpool. 1597a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng for (unsigned i = 0, e = CPUsers.size(); i != e; ++i) { 1598a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng CPUser &U = CPUsers[i]; 1599a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Opcode = U.MI->getOpcode(); 1600a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned NewOpc = 0; 1601a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Scale = 1; 1602a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Bits = 0; 1603a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng switch (Opcode) { 1604a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng default: break; 16056b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson case ARM::t2LEApcrel: 1606a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (isARMLowRegister(U.MI->getOperand(0).getReg())) { 1607a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng NewOpc = ARM::tLEApcrel; 1608a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Bits = 8; 1609a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Scale = 4; 1610a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1611a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng break; 1612a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng case ARM::t2LDRpci: 1613a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (isARMLowRegister(U.MI->getOperand(0).getReg())) { 1614a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng NewOpc = ARM::tLDRpci; 1615a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Bits = 8; 1616a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Scale = 4; 1617a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1618a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng break; 1619a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1620a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1621a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (!NewOpc) 1622a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng continue; 1623a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1624a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned UserOffset = GetOffsetOf(U.MI) + 4; 1625a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned MaxOffs = ((1 << Bits) - 1) * Scale; 1626a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // FIXME: Check if offset is multiple of scale if scale is not 4. 1627a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (CPEIsInRange(U.MI, UserOffset, U.CPEMI, MaxOffs, false, true)) { 1628a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng U.MI->setDesc(TII->get(NewOpc)); 1629a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MachineBasicBlock *MBB = U.MI->getParent(); 1630a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size -= 2; 16312fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen AdjustBBOffsetsAfter(MBB); 1632a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng ++NumT2CPShrunk; 1633a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MadeChange = true; 1634a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1635a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1636a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1637a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MadeChange |= OptimizeThumb2Branches(MF); 163801dec0e545de18aadcd3911563a93d10a625be80Jim Grosbach MadeChange |= OptimizeThumb2JumpTables(MF); 1639a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng return MadeChange; 1640a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng} 1641a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1642a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Chengbool ARMConstantIslands::OptimizeThumb2Branches(MachineFunction &MF) { 164331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng bool MadeChange = false; 164431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 164531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng for (unsigned i = 0, e = ImmBranches.size(); i != e; ++i) { 164631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng ImmBranch &Br = ImmBranches[i]; 164731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Opcode = Br.MI->getOpcode(); 164831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned NewOpc = 0; 164931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Scale = 1; 165031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Bits = 0; 165131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng switch (Opcode) { 165231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng default: break; 165331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng case ARM::t2B: 165431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng NewOpc = ARM::tB; 165531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Bits = 11; 165631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Scale = 2; 165731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng break; 1658de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng case ARM::t2Bcc: { 165931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng NewOpc = ARM::tBcc; 166031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Bits = 8; 1661de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Scale = 2; 166231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng break; 166331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 1664de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1665de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (NewOpc) { 1666de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned MaxOffs = ((1 << (Bits-1))-1) * Scale; 1667de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MachineBasicBlock *DestBB = Br.MI->getOperand(0).getMBB(); 1668de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (BBIsInRange(Br.MI, DestBB, MaxOffs)) { 1669de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Br.MI->setDesc(TII->get(NewOpc)); 1670de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MachineBasicBlock *MBB = Br.MI->getParent(); 1671a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size -= 2; 16722fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen AdjustBBOffsetsAfter(MBB); 1673de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng ++NumT2BrShrunk; 1674de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MadeChange = true; 1675de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1676de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1677de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng 1678de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Opcode = Br.MI->getOpcode(); 1679de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (Opcode != ARM::tBcc) 168031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng continue; 168131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 1682de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = 0; 1683de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned PredReg = 0; 1684de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng ARMCC::CondCodes Pred = llvm::getInstrPredicate(Br.MI, PredReg); 1685de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (Pred == ARMCC::EQ) 1686de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = ARM::tCBZ; 1687de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng else if (Pred == ARMCC::NE) 1688de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = ARM::tCBNZ; 1689de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (!NewOpc) 1690de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng continue; 169131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng MachineBasicBlock *DestBB = Br.MI->getOperand(0).getMBB(); 1692de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng // Check if the distance is within 126. Subtract starting offset by 2 1693de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng // because the cmp will be eliminated. 1694de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned BrOffset = GetOffsetOf(Br.MI) + 4 - 2; 1695a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen unsigned DestOffset = BBInfo[DestBB->getNumber()].Offset; 1696de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (BrOffset < DestOffset && (DestOffset - BrOffset) <= 126) { 16970539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MachineBasicBlock::iterator CmpMI = Br.MI; 16980539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng if (CmpMI != Br.MI->getParent()->begin()) { 16990539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng --CmpMI; 17000539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng if (CmpMI->getOpcode() == ARM::tCMPi8) { 17010539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng unsigned Reg = CmpMI->getOperand(0).getReg(); 17020539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng Pred = llvm::getInstrPredicate(CmpMI, PredReg); 17030539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng if (Pred == ARMCC::AL && 17040539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng CmpMI->getOperand(1).getImm() == 0 && 17050539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng isARMLowRegister(Reg)) { 17060539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MachineBasicBlock *MBB = Br.MI->getParent(); 17070539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MachineInstr *NewBR = 17080539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng BuildMI(*MBB, CmpMI, Br.MI->getDebugLoc(), TII->get(NewOpc)) 17090539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng .addReg(Reg).addMBB(DestBB,Br.MI->getOperand(0).getTargetFlags()); 17100539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng CmpMI->eraseFromParent(); 17110539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng Br.MI->eraseFromParent(); 17120539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng Br.MI = NewBR; 1713a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size -= 2; 17142fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen AdjustBBOffsetsAfter(MBB); 17150539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng ++NumCBZ; 17160539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MadeChange = true; 17170539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng } 1718de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1719de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 172031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 172131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 172231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 172331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng return MadeChange; 1724a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng} 1725a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1726a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng/// OptimizeThumb2JumpTables - Use tbb / tbh instructions to generate smaller 1727a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng/// jumptables when it's possible. 17285657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::OptimizeThumb2JumpTables(MachineFunction &MF) { 17295657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool MadeChange = false; 17305657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17315657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng // FIXME: After the tables are shrunk, can we get rid some of the 17325657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng // constantpool tables? 17331fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineJumpTableInfo *MJTI = MF.getJumpTableInfo(); 1734b1e803985d3378538ae9cff7eed4102c002d1e22Chris Lattner if (MJTI == 0) return false; 173526b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach 17365657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 17375657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned i = 0, e = T2JumpTables.size(); i != e; ++i) { 17385657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineInstr *MI = T2JumpTables[i]; 1739e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng const MCInstrDesc &MCID = MI->getDesc(); 1740e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng unsigned NumOps = MCID.getNumOperands(); 17415a96b3dad2f634c9081c8b2b6c2575441dc5a2bdEvan Cheng unsigned JTOpIdx = NumOps - (MI->isPredicable() ? 3 : 2); 17425657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineOperand JTOP = MI->getOperand(JTOpIdx); 17435657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned JTI = JTOP.getIndex(); 17445657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng assert(JTI < JT.size()); 17455657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17461fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach bool ByteOk = true; 17471fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach bool HalfWordOk = true; 174880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach unsigned JTOffset = GetOffsetOf(MI) + 4; 174980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 17505657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned j = 0, ee = JTBBs.size(); j != ee; ++j) { 17515657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *MBB = JTBBs[j]; 1752a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen unsigned DstOffset = BBInfo[MBB->getNumber()].Offset; 17538770f747a98194056805f1b7cbcb0b75a7633b87Evan Cheng // Negative offset is not ok. FIXME: We should change BB layout to make 17548770f747a98194056805f1b7cbcb0b75a7633b87Evan Cheng // sure all the branches are forward. 1755d26b14c34cbcee1448b86b524578fc51cc979023Evan Cheng if (ByteOk && (DstOffset - JTOffset) > ((1<<8)-1)*2) 17565657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng ByteOk = false; 175725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned TBHLimit = ((1<<16)-1)*2; 175825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng if (HalfWordOk && (DstOffset - JTOffset) > TBHLimit) 17595657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng HalfWordOk = false; 17605657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!ByteOk && !HalfWordOk) 17615657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 17625657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17635657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17645657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (ByteOk || HalfWordOk) { 17655657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 17665657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned BaseReg = MI->getOperand(0).getReg(); 17675657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool BaseRegKill = MI->getOperand(0).isKill(); 17685657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!BaseRegKill) 17695657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17705657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned IdxReg = MI->getOperand(1).getReg(); 17715657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool IdxRegKill = MI->getOperand(1).isKill(); 1772c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 1773c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // Scan backwards to find the instruction that defines the base 1774c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // register. Due to post-RA scheduling, we can't count on it 1775c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // immediately preceding the branch instruction. 17765657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock::iterator PrevI = MI; 1777c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineBasicBlock::iterator B = MBB->begin(); 1778c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach while (PrevI != B && !PrevI->definesRegister(BaseReg)) 1779c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach --PrevI; 1780c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 1781c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // If for some reason we didn't find it, we can't do anything, so 1782c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // just skip this one. 1783c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach if (!PrevI->definesRegister(BaseReg)) 17845657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17855657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 1786c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineInstr *AddrMI = PrevI; 17875657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool OptOk = true; 178826b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach // Examine the instruction that calculates the jumptable entry address. 1789c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // Make sure it only defines the base register and kills any uses 1790c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // other than the index register. 17915657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned k = 0, eee = AddrMI->getNumOperands(); k != eee; ++k) { 17925657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const MachineOperand &MO = AddrMI->getOperand(k); 17935657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!MO.isReg() || !MO.getReg()) 17945657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17955657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (MO.isDef() && MO.getReg() != BaseReg) { 17965657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng OptOk = false; 17975657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 17985657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17995657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (MO.isUse() && !MO.isKill() && MO.getReg() != IdxReg) { 18005657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng OptOk = false; 18015657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 18025657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 18035657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 18045657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!OptOk) 18055657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 18065657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 18076b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson // Now scan back again to find the tLEApcrel or t2LEApcrelJT instruction 1808c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // that gave us the initial base register definition. 1809c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach for (--PrevI; PrevI != B && !PrevI->definesRegister(BaseReg); --PrevI) 1810c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach ; 1811c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 18126b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson // The instruction should be a tLEApcrel or t2LEApcrelJT; we want 1813a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // to delete it as well. 1814c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineInstr *LeaMI = PrevI; 1815a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if ((LeaMI->getOpcode() != ARM::tLEApcrelJT && 18166b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson LeaMI->getOpcode() != ARM::t2LEApcrelJT) || 18175657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng LeaMI->getOperand(0).getReg() != BaseReg) 181825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OptOk = false; 181925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 182025f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng if (!OptOk) 182125f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng continue; 182225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 1823d092a87ba3f905a6801a0bdf816267329cf0391cJim Grosbach unsigned Opc = ByteOk ? ARM::t2TBB_JT : ARM::t2TBH_JT; 182425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MachineInstr *NewJTMI = BuildMI(MBB, MI->getDebugLoc(), TII->get(Opc)) 182525f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addReg(IdxReg, getKillRegState(IdxRegKill)) 182625f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addJumpTableIndex(JTI, JTOP.getTargetFlags()) 182725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addImm(MI->getOperand(JTOpIdx+1).getImm()); 182825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng // FIXME: Insert an "ALIGN" instruction to ensure the next instruction 182925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng // is 2-byte aligned. For now, asm printer will fix it up. 183025f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned NewSize = TII->GetInstSizeInBytes(NewJTMI); 183125f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned OrigSize = TII->GetInstSizeInBytes(AddrMI); 183225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OrigSize += TII->GetInstSizeInBytes(LeaMI); 183325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OrigSize += TII->GetInstSizeInBytes(MI); 183425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 183525f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng AddrMI->eraseFromParent(); 183625f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng LeaMI->eraseFromParent(); 183725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MI->eraseFromParent(); 183825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 183925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng int delta = OrigSize - NewSize; 1840a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size -= delta; 18412fe71c5ef4b1816993bafeec501e742a7fa69b46Jakob Stoklund Olesen AdjustBBOffsetsAfter(MBB); 184225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 184325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng ++NumTBs; 184425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MadeChange = true; 18455657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 18465657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 18475657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 18485657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return MadeChange; 18495657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng} 18501fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 18519249efe4c7451e83fb4c904fd7fcc8edfe08d815Jim Grosbach/// ReorderThumb2JumpTables - Adjust the function's block layout to ensure that 18529249efe4c7451e83fb4c904fd7fcc8edfe08d815Jim Grosbach/// jump tables always branch forwards, since that's what tbb and tbh need. 185380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbachbool ARMConstantIslands::ReorderThumb2JumpTables(MachineFunction &MF) { 185480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach bool MadeChange = false; 185580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 185680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineJumpTableInfo *MJTI = MF.getJumpTableInfo(); 1857b1e803985d3378538ae9cff7eed4102c002d1e22Chris Lattner if (MJTI == 0) return false; 185826b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach 185980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 186080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (unsigned i = 0, e = T2JumpTables.size(); i != e; ++i) { 186180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineInstr *MI = T2JumpTables[i]; 1862e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng const MCInstrDesc &MCID = MI->getDesc(); 1863e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng unsigned NumOps = MCID.getNumOperands(); 18645a96b3dad2f634c9081c8b2b6c2575441dc5a2bdEvan Cheng unsigned JTOpIdx = NumOps - (MI->isPredicable() ? 3 : 2); 186580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineOperand JTOP = MI->getOperand(JTOpIdx); 186680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach unsigned JTI = JTOP.getIndex(); 186780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach assert(JTI < JT.size()); 186880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 186980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // We prefer if target blocks for the jump table come after the jump 187080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // instruction so we can use TB[BH]. Loop through the target blocks 187180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // and try to adjust them such that that's true. 187208cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach int JTNumber = MI->getParent()->getNumber(); 187380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 187480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (unsigned j = 0, ee = JTBBs.size(); j != ee; ++j) { 187580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *MBB = JTBBs[j]; 187608cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach int DTNumber = MBB->getNumber(); 187780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 187808cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach if (DTNumber < JTNumber) { 187980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // The destination precedes the switch. Try to move the block forward 188080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // so we have a positive offset. 188180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *NewBB = 188280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach AdjustJTTargetBlockForward(MBB, MI->getParent()); 188380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach if (NewBB) 188400a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach MJTI->ReplaceMBBInJumpTable(JTI, JTBBs[j], NewBB); 188580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MadeChange = true; 188680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 188780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 188880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 188980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 189080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach return MadeChange; 189180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach} 189280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 18931fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim GrosbachMachineBasicBlock *ARMConstantIslands:: 18941fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim GrosbachAdjustJTTargetBlockForward(MachineBasicBlock *BB, MachineBasicBlock *JTBB) 18951fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach{ 18961fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineFunction &MF = *BB->getParent(); 18971fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 189803e2d44722c1ebd3953007db0579147b46efba18Jim Grosbach // If the destination block is terminated by an unconditional branch, 189980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // try to move it; otherwise, create a new block following the jump 190008cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // table that branches back to the actual target. This is a very simple 190108cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // heuristic. FIXME: We can definitely improve it. 190280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *TBB = 0, *FBB = 0; 190380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach SmallVector<MachineOperand, 4> Cond; 1904a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach SmallVector<MachineOperand, 4> CondPrior; 1905a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MachineFunction::iterator BBi = BB; 1906a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MachineFunction::iterator OldPrior = prior(BBi); 190700a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach 1908ca215e7804ca5d85e19e31850c3ba3d155624e89Jim Grosbach // If the block terminator isn't analyzable, don't try to move the block 1909a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach bool B = TII->AnalyzeBranch(*BB, TBB, FBB, Cond); 1910ca215e7804ca5d85e19e31850c3ba3d155624e89Jim Grosbach 1911a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach // If the block ends in an unconditional branch, move it. The prior block 1912a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach // has to have an analyzable terminator for us to move this one. Be paranoid 191308cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // and make sure we're not trying to move the entry block of the function. 1914a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach if (!B && Cond.empty() && BB != MF.begin() && 1915a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach !TII->AnalyzeBranch(*OldPrior, TBB, FBB, CondPrior)) { 191680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach BB->moveAfter(JTBB); 191780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach OldPrior->updateTerminator(); 191800a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach BB->updateTerminator(); 191908cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // Update numbering to account for the block being moved. 1920a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MF.RenumberBlocks(); 192180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach ++NumJTMoved; 192280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach return NULL; 192380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 19241fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 19251fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Create a new MBB for the code after the jump BB. 19261fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineBasicBlock *NewBB = 19271fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MF.CreateMachineBasicBlock(JTBB->getBasicBlock()); 19281fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineFunction::iterator MBBI = JTBB; ++MBBI; 19291fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MF.insert(MBBI, NewBB); 19301fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 19311fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Add an unconditional branch from NewBB to BB. 19321fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // There doesn't seem to be meaningful DebugInfo available; this doesn't 19331fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // correspond directly to anything in the source. 19341fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach assert (isThumb2 && "Adjusting for TB[BH] but not in Thumb2?"); 193551f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(NewBB, DebugLoc(), TII->get(ARM::t2B)).addMBB(BB) 193651f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson .addImm(ARMCC::AL).addReg(0); 19371fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 193800a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach // Update internal data structures to account for the newly inserted MBB. 193900a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach MF.RenumberBlocks(NewBB); 194000a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach 19411fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Update the CFG. 19421fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach NewBB->addSuccessor(BB); 19431fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach JTBB->removeSuccessor(BB); 19441fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach JTBB->addSuccessor(NewBB); 19451fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 194680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach ++NumJTInserted; 19471fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach return NewBB; 19481fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach} 1949