ARMConstantIslandPass.cpp revision 5bb32530bc1adb970eee2ac18508ea2876a2f410
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 85a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BasicBlockInfo() : Offset(0), Size(0) {} 86a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BasicBlockInfo(unsigned o, unsigned s) : Offset(o), Size(s) {} 875bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen 885bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen /// Compute the offset immediately following this block. 895bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen unsigned postOffset() const { return Offset + Size; } 90a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen }; 918494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 92a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen std::vector<BasicBlockInfo> BBInfo; 9399c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 94a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// WaterList - A sorted list of basic blocks where islands could be placed 95a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// (i.e. blocks that don't fall through to the following block, due 96a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// to a return, unreachable, or unconditional branch). 97e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<MachineBasicBlock*> WaterList; 98c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 99b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson /// NewWaterList - The subset of WaterList that was created since the 100b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson /// previous iteration by inserting unconditional branches. 101b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson SmallSet<MachineBasicBlock*, 4> NewWaterList; 102b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 103034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson typedef std::vector<MachineBasicBlock*>::iterator water_iterator; 104034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson 105a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// CPUser - One user of a constant pool, keeping the machine instruction 106a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// pointer, the constant pool being referenced, and the max displacement 107549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// allowed from the instruction to the CP. The HighWaterMark records the 108549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// highest basic block where a new CPEntry can be placed. To ensure this 109549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// pass terminates, the CP entries are initially placed at the end of the 110549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// function and then move monotonically to lower addresses. The 111549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// exception to this rule is when the current CP entry for a particular 112549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// CPUser is out of range, but there is another CP entry for the same 113549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// constant value in range. We want to use the existing in-range CP 114549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// entry, but if it later moves out of range, the search for new water 115549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// should resume where it left off. The HighWaterMark is used to record 116549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// that point. 117a8e2989ece6dc46df59b0768184028257f913843Evan Cheng struct CPUser { 118a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineInstr *MI; 119a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineInstr *CPEMI; 120549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson MachineBasicBlock *HighWaterMark; 121a8e2989ece6dc46df59b0768184028257f913843Evan Cheng unsigned MaxDisp; 1225d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool NegOk; 123d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool IsSoImm; 124d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng CPUser(MachineInstr *mi, MachineInstr *cpemi, unsigned maxdisp, 125d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool neg, bool soimm) 126549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson : MI(mi), CPEMI(cpemi), MaxDisp(maxdisp), NegOk(neg), IsSoImm(soimm) { 127549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson HighWaterMark = CPEMI->getParent(); 128549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson } 129a8e2989ece6dc46df59b0768184028257f913843Evan Cheng }; 1308494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 131a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// CPUsers - Keep track of all of the machine instructions that use various 132a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// constant pools and their max displacement. 133e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<CPUser> CPUsers; 1348494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 135c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// CPEntry - One per constant pool entry, keeping the machine instruction 136c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// pointer, the constpool index, and the number of CPUser's which 137c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// reference this entry. 138c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng struct CPEntry { 139c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineInstr *CPEMI; 140c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng unsigned CPI; 141c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng unsigned RefCount; 142c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntry(MachineInstr *cpemi, unsigned cpi, unsigned rc = 0) 143c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng : CPEMI(cpemi), CPI(cpi), RefCount(rc) {} 144c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng }; 145c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 146c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// CPEntries - Keep track of all of the constant pool entry machine 14788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// instructions. For each original constpool index (i.e. those that 14888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// existed upon entry to this pass), it keeps a vector of entries. 14988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// Original elements are cloned as we go along; the clones are 15088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// put in the vector of the original element, but have distinct CPIs. 151c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng std::vector<std::vector<CPEntry> > CPEntries; 1528494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 153af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// ImmBranch - One per immediate branch, keeping the machine instruction 154af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// pointer, conditional or unconditional, the max displacement, 155af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// and (if isCond is true) the corresponding unconditional branch 156af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// opcode. 157af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng struct ImmBranch { 158af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MachineInstr *MI; 159c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng unsigned MaxDisp : 31; 160c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng bool isCond : 1; 161af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng int UncondBr; 162c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng ImmBranch(MachineInstr *mi, unsigned maxdisp, bool cond, int ubr) 163c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng : MI(mi), MaxDisp(maxdisp), isCond(cond), UncondBr(ubr) {} 164af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng }; 165af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 1662706f9771de8e90ee6379e70afedd91892bb9c8cEvan Cheng /// ImmBranches - Keep track of all the immediate branch instructions. 167af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// 168e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<ImmBranch> ImmBranches; 169af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 170d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// PushPopMIs - Keep track of all the Thumb push / pop instructions. 171d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// 172c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng SmallVector<MachineInstr*, 4> PushPopMIs; 173d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1745657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng /// T2JumpTables - Keep track of all the Thumb2 jumptable instructions. 1755657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng SmallVector<MachineInstr*, 4> T2JumpTables; 1765657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 177d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// HasFarJump - True if any far jump instruction has been emitted during 178d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// the branch fix up pass. 179d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng bool HasFarJump; 180d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1814d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach /// HasInlineAsm - True if the function contains inline assembly. 1824d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach bool HasInlineAsm; 1834d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach 1842062875a7d8f7dd94a20d9e3a298e9e216efb4b5Chris Lattner const ARMInstrInfo *TII; 18525f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng const ARMSubtarget *STI; 1868593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen ARMFunctionInfo *AFI; 187b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen bool isThumb; 188d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool isThumb1; 1895e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin bool isThumb2; 190a8e2989ece6dc46df59b0768184028257f913843Evan Cheng public: 1911997473cf72957d0e70322e2fe6fe2ab141c58a6Devang Patel static char ID; 19290c579de5a383cee278acc3f7e7b9d0a656e6a35Owen Anderson ARMConstantIslands() : MachineFunctionPass(ID) {} 193794fd75c67a2cdc128d67342c6d88a504d186896Devang Patel 1945657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng virtual bool runOnMachineFunction(MachineFunction &MF); 195a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 196a8e2989ece6dc46df59b0768184028257f913843Evan Cheng virtual const char *getPassName() const { 197af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng return "ARM constant island placement and branch shortening pass"; 198a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 1998494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 200a8e2989ece6dc46df59b0768184028257f913843Evan Cheng private: 2015657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng void DoInitialPlacement(MachineFunction &MF, 202e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<MachineInstr*> &CPEMIs); 203c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntry *findConstPoolEntry(unsigned CPI, const MachineInstr *CPEMI); 20480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach void JumpTableFunctionScan(MachineFunction &MF); 2055657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng void InitialFunctionScan(MachineFunction &MF, 206e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng const std::vector<MachineInstr*> &CPEMIs); 2070c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng MachineBasicBlock *SplitBlockBeforeInstr(MachineInstr *MI); 208a8e2989ece6dc46df59b0768184028257f913843Evan Cheng void UpdateForInsertedWaterBlock(MachineBasicBlock *NewBB); 20999c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen void AdjustBBOffsetsAfter(MachineBasicBlock *BB, int delta); 210ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng bool DecrementOldEntry(unsigned CPI, MachineInstr* CPEMI); 21188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen int LookForExistingCPEntry(CPUser& U, unsigned UserOffset); 212b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson bool LookForWater(CPUser&U, unsigned UserOffset, water_iterator &WaterIter); 213b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen void CreateNewWater(unsigned CPUserIndex, unsigned UserOffset, 214757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson MachineBasicBlock *&NewMBB); 2155657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool HandleConstantPoolUser(MachineFunction &MF, unsigned CPUserIndex); 216ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng void RemoveDeadCPEMI(MachineInstr *CPEMI); 217ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng bool RemoveUnusedCPEntries(); 2188494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson bool CPEIsInRange(MachineInstr *MI, unsigned UserOffset, 2195d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng MachineInstr *CPEMI, unsigned Disp, bool NegOk, 2205d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool DoDump = false); 22199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen bool WaterIsInRange(unsigned UserOffset, MachineBasicBlock *Water, 2225d9c4b60204d741c213456e21b87e9af6a3dc627Dale Johannesen CPUser &U); 22399c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen bool OffsetIsInRange(unsigned UserOffset, unsigned TrialOffset, 224d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng unsigned Disp, bool NegativeOK, bool IsSoImm = false); 225c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng bool BBIsInRange(MachineInstr *MI, MachineBasicBlock *BB, unsigned Disp); 2265657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool FixUpImmediateBr(MachineFunction &MF, ImmBranch &Br); 2275657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool FixUpConditionalBr(MachineFunction &MF, ImmBranch &Br); 2285657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool FixUpUnconditionalBr(MachineFunction &MF, ImmBranch &Br); 229d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng bool UndoLRSpillRestore(); 230a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng bool OptimizeThumb2Instructions(MachineFunction &MF); 231a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng bool OptimizeThumb2Branches(MachineFunction &MF); 23280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach bool ReorderThumb2JumpTables(MachineFunction &MF); 2335657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool OptimizeThumb2JumpTables(MachineFunction &MF); 2341fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineBasicBlock *AdjustJTTargetBlockForward(MachineBasicBlock *BB, 2351fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineBasicBlock *JTBB); 236a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 237a8e2989ece6dc46df59b0768184028257f913843Evan Cheng unsigned GetOffsetOf(MachineInstr *MI) const; 2388593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen void dumpBBs(); 2395657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng void verify(MachineFunction &MF); 240a8e2989ece6dc46df59b0768184028257f913843Evan Cheng }; 2411997473cf72957d0e70322e2fe6fe2ab141c58a6Devang Patel char ARMConstantIslands::ID = 0; 242a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 243a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 2448593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// verify - check BBOffsets, BBSizes, alignment of islands 2455657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengvoid ARMConstantIslands::verify(MachineFunction &MF) { 246a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen for (unsigned i = 1, e = BBInfo.size(); i != e; ++i) 2475bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen assert(BBInfo[i-1].postOffset() == BBInfo[i].Offset); 248d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (!isThumb) 249d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return; 250d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng#ifndef NDEBUG 2515657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 252d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MBBI != E; ++MBBI) { 253d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MachineBasicBlock *MBB = MBBI; 254d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (!MBB->empty() && 255d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MBB->begin()->getOpcode() == ARM::CONSTPOOL_ENTRY) { 256d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng unsigned MBBId = MBB->getNumber(); 2574d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach assert(HasInlineAsm || 258a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen (BBInfo[MBBId].Offset%4 == 0 && BBInfo[MBBId].Size%4 == 0) || 259a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen (BBInfo[MBBId].Offset%4 != 0 && BBInfo[MBBId].Size%4 != 0)); 2608593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 2618593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 2624d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach for (unsigned i = 0, e = CPUsers.size(); i != e; ++i) { 2634d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach CPUser &U = CPUsers[i]; 2644d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach unsigned UserOffset = GetOffsetOf(U.MI) + (isThumb ? 4 : 8); 265a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach unsigned CPEOffset = GetOffsetOf(U.CPEMI); 266a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach unsigned Disp = UserOffset < CPEOffset ? CPEOffset - UserOffset : 267a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach UserOffset - CPEOffset; 268a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach assert(Disp <= U.MaxDisp || "Constant pool entry out of range!"); 2694d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach } 270a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach#endif 2718593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen} 2728593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 2738593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// print block size and offset information - debugging 2748593e418555fdae21a070357fd8734b4069c17d0Dale Johannesenvoid ARMConstantIslands::dumpBBs() { 275a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen for (unsigned J = 0, E = BBInfo.size(); J !=E; ++J) { 276a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen DEBUG(errs() << "block " << J << " offset " << BBInfo[J].Offset 277a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen << " size " << BBInfo[J].Size << "\n"); 2788593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 2798593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen} 2808593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 281af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng/// createARMConstantIslandPass - returns an instance of the constpool 282af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng/// island pass. 283a8e2989ece6dc46df59b0768184028257f913843Evan ChengFunctionPass *llvm::createARMConstantIslandPass() { 284a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return new ARMConstantIslands(); 285a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 286a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 2875657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::runOnMachineFunction(MachineFunction &MF) { 2885657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineConstantPool &MCP = *MF.getConstantPool(); 2898494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 2902062875a7d8f7dd94a20d9e3a298e9e216efb4b5Chris Lattner TII = (const ARMInstrInfo*)MF.getTarget().getInstrInfo(); 2915657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng AFI = MF.getInfo<ARMFunctionInfo>(); 29225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng STI = &MF.getTarget().getSubtarget<ARMSubtarget>(); 29325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 294b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen isThumb = AFI->isThumbFunction(); 295d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng isThumb1 = AFI->isThumb1OnlyFunction(); 2965e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin isThumb2 = AFI->isThumb2Function(); 297d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 298d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng HasFarJump = false; 2994d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach HasInlineAsm = false; 300d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 301a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Renumber all of the machine basic blocks in the function, guaranteeing that 302a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // the numbers agree with the position of the block in the function. 3035657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.RenumberBlocks(); 304a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 30580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // Try to reorder and otherwise adjust the block layout to make good use 30680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // of the TB[BH] instructions. 30780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach bool MadeChange = false; 30880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach if (isThumb2 && AdjustJumpTableBlocks) { 30980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach JumpTableFunctionScan(MF); 31080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MadeChange |= ReorderThumb2JumpTables(MF); 31180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // Data is out of date, so clear it. It'll be re-computed later. 31280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach T2JumpTables.clear(); 31380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // Blocks may have shifted around. Keep the numbering up to date. 31480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MF.RenumberBlocks(); 31580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 31680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 317d26b14c34cbcee1448b86b524578fc51cc979023Evan Cheng // Thumb1 functions containing constant pools get 4-byte alignment. 318d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // This is so we can keep exact track of where the alignment padding goes. 319d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 3207d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner // ARM and Thumb2 functions need to be 4-byte aligned. 3217d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner if (!isThumb1) 3227d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner MF.EnsureAlignment(2); // 2 = log2(4) 32356c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen 324a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Perform the initial placement of the constant pool entries. To start with, 325a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // we put them all at the end of the function. 326e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<MachineInstr*> CPEMIs; 32756c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen if (!MCP.isEmpty()) { 3285657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng DoInitialPlacement(MF, CPEMIs); 329d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (isThumb1) 3307d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner MF.EnsureAlignment(2); // 2 = log2(4) 33156c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen } 3328494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 333a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// The next UID to take is the first unused one. 3345de5d4b6d0eb3fd379fa571d82f6fa764460b3b8Evan Cheng AFI->initPICLabelUId(CPEMIs.size()); 3358494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 336a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Do the initial scan of the function, building up information about the 337a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // sizes of each block, the location of all the water, and finding all of the 338a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // constant pool users. 3395657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng InitialFunctionScan(MF, CPEMIs); 340a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CPEMIs.clear(); 3418086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen DEBUG(dumpBBs()); 3428086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 3438494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 344ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng /// Remove dead constant pool entries. 345cd080249fc249a51d8b0021a651d8b9d4a4977e0Bill Wendling MadeChange |= RemoveUnusedCPEntries(); 346ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 347d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // Iteratively place constant pool entries and fix up branches until there 348d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // is no change. 349b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng unsigned NoCPIters = 0, NoBRIters = 0; 350d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng while (true) { 351b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng bool CPChange = false; 352a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned i = 0, e = CPUsers.size(); i != e; ++i) 353b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng CPChange |= HandleConstantPoolUser(MF, i); 354b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng if (CPChange && ++NoCPIters > 30) 355b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng llvm_unreachable("Constant Island pass failed to converge!"); 3568202010364e1bfe6111f1ce62f154499b80877fbEvan Cheng DEBUG(dumpBBs()); 35726b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach 358b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Clear NewWaterList now. If we split a block for branches, it should 359b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // appear as "new water" for the next iteration of constant pool placement. 360b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.clear(); 361b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng 362b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng bool BRChange = false; 363af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng for (unsigned i = 0, e = ImmBranches.size(); i != e; ++i) 364b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng BRChange |= FixUpImmediateBr(MF, ImmBranches[i]); 365b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng if (BRChange && ++NoBRIters > 30) 366b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng llvm_unreachable("Branch Fix Up pass failed to converge!"); 3678202010364e1bfe6111f1ce62f154499b80877fbEvan Cheng DEBUG(dumpBBs()); 368b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng 369b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng if (!CPChange && !BRChange) 370d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng break; 371d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MadeChange = true; 372d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng } 373ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 374a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // Shrink 32-bit Thumb2 branch, load, and store instructions. 375e44be6381609d31b2d8879dbd5107e01404fa475Evan Cheng if (isThumb2 && !STI->prefers32BitThumb()) 376a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MadeChange |= OptimizeThumb2Instructions(MF); 37725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 3788593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // After a while, this might be made debug-only, but it is not expensive. 3795657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng verify(MF); 3808593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 38126b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach // If LR has been forced spilled and no far jump (i.e. BL) has been issued, 38226b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach // undo the spill / restore of LR if possible. 3835657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (isThumb && !HasFarJump && AFI->isLRSpilledForFarJump()) 384d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MadeChange |= UndoLRSpillRestore(); 385d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 38698b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov // Save the mapping between original and cloned constpool entries. 38798b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov for (unsigned i = 0, e = CPEntries.size(); i != e; ++i) { 38898b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov for (unsigned j = 0, je = CPEntries[i].size(); j != je; ++j) { 38998b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov const CPEntry & CPE = CPEntries[i][j]; 39098b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov AFI->recordCPEClone(i, CPE.CPI); 39198b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov } 39298b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov } 39398b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov 394b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng DEBUG(errs() << '\n'; dumpBBs()); 395b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng 396a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo.clear(); 397a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.clear(); 398a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CPUsers.clear(); 399c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntries.clear(); 400af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng ImmBranches.clear(); 401c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng PushPopMIs.clear(); 4025657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng T2JumpTables.clear(); 403d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 404d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return MadeChange; 405a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 406a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 407a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// DoInitialPlacement - Perform the initial placement of the constant pool 408a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// entries. To start with, we put them all at the end of the function. 4095657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengvoid ARMConstantIslands::DoInitialPlacement(MachineFunction &MF, 4108494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson std::vector<MachineInstr*> &CPEMIs) { 411a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Create the basic block to hold the CPE's. 4125657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *BB = MF.CreateMachineBasicBlock(); 4135657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.push_back(BB); 4148494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 4153e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen // Mark the basic block as 4-byte aligned as required by the const-pool. 4163e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen BB->setAlignment(2); 4173e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen 418a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add all of the constants from the constant pool to the end block, use an 419a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // identity mapping of CPI's to CPE's. 420a8e2989ece6dc46df59b0768184028257f913843Evan Cheng const std::vector<MachineConstantPoolEntry> &CPs = 4215657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.getConstantPool()->getConstants(); 4228494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 4235657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const TargetData &TD = *MF.getTarget().getTargetData(); 424a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned i = 0, e = CPs.size(); i != e; ++i) { 425777d2306b36816a53bc1ae1244c0dc7d998ae691Duncan Sands unsigned Size = TD.getTypeAllocSize(CPs[i].getType()); 426a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Verify that all constant pool entries are a multiple of 4 bytes. If not, 427a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // we would have to pad them out or something so that instructions stay 428a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // aligned. 429a8e2989ece6dc46df59b0768184028257f913843Evan Cheng assert((Size & 3) == 0 && "CP Entry not multiple of 4 bytes!"); 430a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineInstr *CPEMI = 431c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(BB, DebugLoc(), TII->get(ARM::CONSTPOOL_ENTRY)) 432c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner .addImm(i).addConstantPoolIndex(i).addImm(Size); 433a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CPEMIs.push_back(CPEMI); 434c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 435c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Add a new CPEntry, but no corresponding CPUser yet. 436c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng std::vector<CPEntry> CPEs; 437c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEs.push_back(CPEntry(CPEMI, i)); 438c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntries.push_back(CPEs); 439fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCPEs; 440893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Moved CPI#" << i << " to end of function as #" << i 441893e1c90a03a53cf13f73849324e83612688428aChris Lattner << "\n"); 442a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 443a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 444a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 44588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// BBHasFallthrough - Return true if the specified basic block can fallthrough 446a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// into the block immediately after it. 447a8e2989ece6dc46df59b0768184028257f913843Evan Chengstatic bool BBHasFallthrough(MachineBasicBlock *MBB) { 448a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Get the next machine basic block in the function. 449a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineFunction::iterator MBBI = MBB; 45018f30e6f5e80787808fe1455742452a5210afe07Jim Grosbach // Can't fall off end of function. 45118f30e6f5e80787808fe1455742452a5210afe07Jim Grosbach if (llvm::next(MBBI) == MBB->getParent()->end()) 452a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return false; 4538494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 4547896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineBasicBlock *NextBB = llvm::next(MBBI); 455a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::succ_iterator I = MBB->succ_begin(), 456a8e2989ece6dc46df59b0768184028257f913843Evan Cheng E = MBB->succ_end(); I != E; ++I) 457a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (*I == NextBB) 458a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return true; 4598494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 460a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return false; 461a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 462a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 463c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// findConstPoolEntry - Given the constpool index and CONSTPOOL_ENTRY MI, 464c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// look up the corresponding CPEntry. 465c99ef085b90b32952b484e8843fb66ad65215b61Evan ChengARMConstantIslands::CPEntry 466c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng*ARMConstantIslands::findConstPoolEntry(unsigned CPI, 467c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng const MachineInstr *CPEMI) { 468c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng std::vector<CPEntry> &CPEs = CPEntries[CPI]; 469c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Number of entries per constpool index should be small, just do a 470c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // linear search. 471c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng for (unsigned i = 0, e = CPEs.size(); i != e; ++i) { 472c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng if (CPEs[i].CPEMI == CPEMI) 473c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return &CPEs[i]; 474c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng } 475c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return NULL; 476c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng} 477c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 47880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// JumpTableFunctionScan - Do a scan of the function, building up 47980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// information about the sizes of each block and the locations of all 48080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// the jump tables. 48180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbachvoid ARMConstantIslands::JumpTableFunctionScan(MachineFunction &MF) { 48280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 48380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MBBI != E; ++MBBI) { 48480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock &MBB = *MBBI; 48580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 48680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 48708cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach I != E; ++I) 48808cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach if (I->getDesc().isBranch() && I->getOpcode() == ARM::t2BR_JT) 48908cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach T2JumpTables.push_back(I); 49080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 49180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach} 49280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 493a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// InitialFunctionScan - Do the initial scan of the function, building up 494a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// information about the sizes of each block, the location of all the water, 495a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// and finding all of the constant pool users. 4965657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengvoid ARMConstantIslands::InitialFunctionScan(MachineFunction &MF, 497e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng const std::vector<MachineInstr*> &CPEMIs) { 4984d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // First thing, see if the function has any inline assembly in it. If so, 4994d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // we have to be conservative about alignment assumptions, as we don't 5004d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // know for sure the size of any instructions in the inline assembly. 5014d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 5024d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach MBBI != E; ++MBBI) { 5034d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach MachineBasicBlock &MBB = *MBBI; 5044d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 5054d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach I != E; ++I) 5064d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach if (I->getOpcode() == ARM::INLINEASM) 5074d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach HasInlineAsm = true; 5084d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach } 5094d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach 5109a4d2e40a02b6e5fab5ccf1c768a52c76f3aec6aBill Wendling // Now go back through the instructions and build up our data structures. 51199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned Offset = 0; 5125657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 513a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MBBI != E; ++MBBI) { 514a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock &MBB = *MBBI; 5158494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 516a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // If this block doesn't fall through into the next MBB, then this is 517a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // 'water' that a constant pool island could be placed. 518a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (!BBHasFallthrough(&MBB)) 519a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.push_back(&MBB); 5208494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 521a8e2989ece6dc46df59b0768184028257f913843Evan Cheng unsigned MBBSize = 0; 522a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 523a8e2989ece6dc46df59b0768184028257f913843Evan Cheng I != E; ++I) { 5249cfcfeb24bf7182d40d8e8a54e350451b67a1136Jim Grosbach if (I->isDebugValue()) 5259cfcfeb24bf7182d40d8e8a54e350451b67a1136Jim Grosbach continue; 526a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add instruction size to MBBSize. 52752e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray MBBSize += TII->GetInstSizeInBytes(I); 528a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 529af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng int Opc = I->getOpcode(); 530749c6f6b5ed301c84aac562e414486549d7b98ebChris Lattner if (I->getDesc().isBranch()) { 531af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng bool isCond = false; 532af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng unsigned Bits = 0; 533af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng unsigned Scale = 1; 534af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng int UOpc = Opc; 535af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng switch (Opc) { 5365657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng default: 5375657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; // Ignore other JT branches 5388593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen case ARM::tBR_JTr: 53966ac53165e17b7c76b8c69e57bde623d44ec492eEvan Cheng // A Thumb1 table jump may involve padding; for the offsets to 5408593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // be right, functions containing these must be 4-byte aligned. 541b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng // tBR_JTr expands to a mov pc followed by .align 2 and then the jump 5426fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // table entries. So this code checks whether offset of tBR_JTr + 2 5436fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // is aligned. That is held in Offset+MBBSize, which already has 5446fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // 2 added in for the size of the mov pc instruction. 5457d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner MF.EnsureAlignment(2U); 5466fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen if ((Offset+MBBSize)%4 != 0 || HasInlineAsm) 5476fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // FIXME: Add a pseudo ALIGN instruction instead. 5486fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen MBBSize += 2; // padding 5498593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen continue; // Does not get an entry in ImmBranches 5505657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng case ARM::t2BR_JT: 5515657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng T2JumpTables.push_back(I); 5525657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; // Does not get an entry in ImmBranches 553af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::Bcc: 554af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng isCond = true; 555af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng UOpc = ARM::B; 556af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // Fallthrough 557af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::B: 558af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 24; 559af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 4; 560af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 561af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::tBcc: 562af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng isCond = true; 563af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng UOpc = ARM::tB; 564af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 8; 565af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 2; 566af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 567af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::tB: 568af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 11; 569af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 2; 570af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 5715e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::t2Bcc: 5725e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin isCond = true; 5735e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin UOpc = ARM::t2B; 5745e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Bits = 20; 5755e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Scale = 2; 5765e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin break; 5775e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::t2B: 5785e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Bits = 24; 5795e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Scale = 2; 5805e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin break; 581af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng } 582b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng 583b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng // Record this immediate branch. 584bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng unsigned MaxOffs = ((1 << (Bits-1))-1) * Scale; 585b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng ImmBranches.push_back(ImmBranch(I, MaxOffs, isCond, UOpc)); 586af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng } 587af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 588d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng if (Opc == ARM::tPUSH || Opc == ARM::tPOP_RET) 589d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng PushPopMIs.push_back(I); 590d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 591d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (Opc == ARM::CONSTPOOL_ENTRY) 592d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng continue; 593d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 594a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Scan the instructions for constant pool operands. 595a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned op = 0, e = I->getNumOperands(); op != e; ++op) 596d735b8019b0f297d7c14b55adcd887af24d8e602Dan Gohman if (I->getOperand(op).isCPI()) { 597a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // We found one. The addressing mode tells us the max displacement 598a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // from the PC that this instruction permits. 5998494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 600a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Basic size info comes from the TSFlags field. 601b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng unsigned Bits = 0; 602b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng unsigned Scale = 1; 6035d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool NegOk = false; 604d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool IsSoImm = false; 605d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 606d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng switch (Opc) { 6078494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson default: 608c23197a26f34f559ea9797de51e187087c039c42Torok Edwin llvm_unreachable("Unknown addressing mode for CP reference!"); 609a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 610d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 611d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // Taking the address of a CP entry. 612d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::LEApcrel: 613d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // This takes a SoImm, which is 8 bit immediate rotated. We'll 614d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // pretend the maximum offset is 255 * 4. Since each instruction 615dec6de92d1425c88f319179fb4a0b0a23f781df9Jim Grosbach // 4 byte wide, this is always correct. We'll check for other 616d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // displacements that fits in a SoImm as well. 617d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 8; 618d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; 6195d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng NegOk = true; 620d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng IsSoImm = true; 621a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 6226b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson case ARM::t2LEApcrel: 623d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 12; 6245d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng NegOk = true; 625a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 626d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::tLEApcrel: 627b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Bits = 8; 628d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; 629a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 630d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 6313e5561247202bae994dd259a2d8dc4eff8f799f3Jim Grosbach case ARM::LDRi12: 632d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::LDRcp: 633971b83b67a9812556cdb97bb58aa96fb37af458dOwen Anderson case ARM::t2LDRpci: 634d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 12; // +-offset_12 635d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng NegOk = true; 636a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 637d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 638d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::tLDRpci: 639b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Bits = 8; 640b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Scale = 4; // +(offset_8*4) 641012f2d97b78e4eb9128f1d491f2c177768dbe527Evan Cheng break; 642d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 643e5165490b7ba24bb2f3043399e0d60e7f3bcf8a5Jim Grosbach case ARM::VLDRD: 644e5165490b7ba24bb2f3043399e0d60e7f3bcf8a5Jim Grosbach case ARM::VLDRS: 645d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 8; 646d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; // +-(offset_8*4) 647d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng NegOk = true; 648055b0310f862b91f33699037ce67d3ab8137c20cEvan Cheng break; 649a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 650b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng 651a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Remember that this is a user of a CP entry. 6528aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner unsigned CPI = I->getOperand(op).getIndex(); 653c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineInstr *CPEMI = CPEMIs[CPI]; 65431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned MaxOffs = ((1 << Bits)-1) * Scale; 655d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng CPUsers.push_back(CPUser(I, CPEMI, MaxOffs, NegOk, IsSoImm)); 656c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 657c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Increment corresponding CPEntry reference count. 658c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntry *CPE = findConstPoolEntry(CPI, CPEMI); 659c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng assert(CPE && "Cannot find a corresponding CPEntry!"); 660c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPE->RefCount++; 6618494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 662a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Instructions can only use one CP entry, don't bother scanning the 663a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // rest of the operands. 664a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 665a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 666a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 6672021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng 6688593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // In thumb mode, if this block is a constpool island, we may need padding 6698593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // so it's aligned on 4 byte boundary. 670b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (isThumb && 67105cc424082f797c5820b19f29f398c9cce9b9928Evan Cheng !MBB.empty() && 6728593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen MBB.begin()->getOpcode() == ARM::CONSTPOOL_ENTRY && 6734d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach ((Offset%4) != 0 || HasInlineAsm)) 6742021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng MBBSize += 2; 6752021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng 676a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo.push_back(BasicBlockInfo(Offset, MBBSize)); 67799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen Offset += MBBSize; 678a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 679a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 680a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 681a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// GetOffsetOf - Return the current offset of the specified machine instruction 682a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// from the start of the function. This offset changes as stuff is moved 683a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// around inside the function. 684a8e2989ece6dc46df59b0768184028257f913843Evan Chengunsigned ARMConstantIslands::GetOffsetOf(MachineInstr *MI) const { 685a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 6868494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 687a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // The offset is composed of two things: the sum of the sizes of all MBB's 688a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // before this instruction's block, and the offset from the start of the block 689a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // it is in. 690a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen unsigned Offset = BBInfo[MBB->getNumber()].Offset; 691a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 6928593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // If we're looking for a CONSTPOOL_ENTRY in Thumb, see if this block has 6938593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // alignment padding, and compensate if so. 6948494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson if (isThumb && 6958494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MI->getOpcode() == ARM::CONSTPOOL_ENTRY && 6964d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach (Offset%4 != 0 || HasInlineAsm)) 6978593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen Offset += 2; 6988593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 699a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Sum instructions before MI in MBB. 700a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::iterator I = MBB->begin(); ; ++I) { 701a8e2989ece6dc46df59b0768184028257f913843Evan Cheng assert(I != MBB->end() && "Didn't find MI in its own basic block?"); 702a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (&*I == MI) return Offset; 70352e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray Offset += TII->GetInstSizeInBytes(I); 704a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 705a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 706a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 707a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// CompareMBBNumbers - Little predicate function to sort the WaterList by MBB 708a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// ID. 709a8e2989ece6dc46df59b0768184028257f913843Evan Chengstatic bool CompareMBBNumbers(const MachineBasicBlock *LHS, 710a8e2989ece6dc46df59b0768184028257f913843Evan Cheng const MachineBasicBlock *RHS) { 711a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return LHS->getNumber() < RHS->getNumber(); 712a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 713a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 714a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// UpdateForInsertedWaterBlock - When a block is newly inserted into the 715a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// machine function, it upsets all of the block numbers. Renumber the blocks 716a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// and update the arrays that parallel this numbering. 717a8e2989ece6dc46df59b0768184028257f913843Evan Chengvoid ARMConstantIslands::UpdateForInsertedWaterBlock(MachineBasicBlock *NewBB) { 718ab4c366274a582dd8146b2820c6b999cad5fce36Duncan Sands // Renumber the MBB's to keep them consecutive. 719a8e2989ece6dc46df59b0768184028257f913843Evan Cheng NewBB->getParent()->RenumberBlocks(NewBB); 7208494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 721a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen // Insert an entry into BBInfo to align it properly with the (newly 722a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // renumbered) block numbers. 723a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo.insert(BBInfo.begin() + NewBB->getNumber(), BasicBlockInfo()); 7248494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 7258494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // Next, update WaterList. Specifically, we need to add NewMBB as having 726a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // available water after it. 727034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson water_iterator IP = 728a8e2989ece6dc46df59b0768184028257f913843Evan Cheng std::lower_bound(WaterList.begin(), WaterList.end(), NewBB, 729a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CompareMBBNumbers); 730a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.insert(IP, NewBB); 731a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 732a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 733a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 734a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// Split the basic block containing MI into two blocks, which are joined by 735b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson/// an unconditional branch. Update data structures and renumber blocks to 7360c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng/// account for this change and returns the newly created block. 7370c61584d05894a5543f690803191a8b0da05b8fcEvan ChengMachineBasicBlock *ARMConstantIslands::SplitBlockBeforeInstr(MachineInstr *MI) { 738a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock *OrigBB = MI->getParent(); 7398e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MachineFunction &MF = *OrigBB->getParent(); 740a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 741a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Create a new MBB for the code after the OrigBB. 7428494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MachineBasicBlock *NewBB = 7438494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MF.CreateMachineBasicBlock(OrigBB->getBasicBlock()); 744a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineFunction::iterator MBBI = OrigBB; ++MBBI; 7458e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MF.insert(MBBI, NewBB); 7468494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 747a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Splice the instructions starting with MI over to NewBB. 748a8e2989ece6dc46df59b0768184028257f913843Evan Cheng NewBB->splice(NewBB->end(), OrigBB, MI, OrigBB->end()); 7498494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 750a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add an unconditional branch from OrigBB to NewBB. 751a9b8b8d62c67e96bc4dc2ed25298c539102f8638Evan Cheng // Note the new unconditional branch is not being recorded. 752b67284057ee130114055309eabe0bcd1af13777dDale Johannesen // There doesn't seem to be meaningful DebugInfo available; this doesn't 753b67284057ee130114055309eabe0bcd1af13777dDale Johannesen // correspond to anything in the source. 75458541fd62707b6856beee3db9e254b0110607bb1Evan Cheng unsigned Opc = isThumb ? (isThumb2 ? ARM::t2B : ARM::tB) : ARM::B; 75551f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson if (!isThumb) 75651f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(OrigBB, DebugLoc(), TII->get(Opc)).addMBB(NewBB); 75751f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson else 75851f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(OrigBB, DebugLoc(), TII->get(Opc)).addMBB(NewBB) 75951f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson .addImm(ARMCC::AL).addReg(0); 760fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumSplit; 7618494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 762a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Update the CFG. All succs of OrigBB are now succs of NewBB. 763e80fba0e6c976039c132c3d5d4fcad569d2259a8Jakob Stoklund Olesen NewBB->transferSuccessors(OrigBB); 7648494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 765a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // OrigBB branches to NewBB. 766a8e2989ece6dc46df59b0768184028257f913843Evan Cheng OrigBB->addSuccessor(NewBB); 7678494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 768a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Update internal data structures to account for the newly inserted MBB. 76988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // This is almost the same as UpdateForInsertedWaterBlock, except that 77088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // the Water goes after OrigBB, not NewBB. 7718e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MF.RenumberBlocks(NewBB); 7728494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 773a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen // Insert an entry into BBInfo to align it properly with the (newly 77488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // renumbered) block numbers. 775a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo.insert(BBInfo.begin() + NewBB->getNumber(), BasicBlockInfo()); 77699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 7778494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // Next, update WaterList. Specifically, we need to add OrigMBB as having 77888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // available water after it (but not if it's already there, which happens 77988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // when splitting before a conditional branch that is followed by an 78088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // unconditional branch - in that case we want to insert NewBB). 781034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson water_iterator IP = 78288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen std::lower_bound(WaterList.begin(), WaterList.end(), OrigBB, 78388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen CompareMBBNumbers); 78488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen MachineBasicBlock* WaterBB = *IP; 78588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (WaterBB == OrigBB) 7867896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner WaterList.insert(llvm::next(IP), NewBB); 78788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen else 78888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen WaterList.insert(IP, OrigBB); 789b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(OrigBB); 79088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 79199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned OrigBBI = OrigBB->getNumber(); 79299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned NewBBI = NewBB->getNumber(); 7938494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 79425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng int delta = isThumb1 ? 2 : 4; 7958086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 7968086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // Figure out how large the OrigBB is. As the first half of the original 7978086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // block, it cannot contain a tablejump. The size includes 7988086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // the new jump we added. (It should be possible to do this without 7998086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // recounting everything, but it's very confusing, and this is rarely 8008086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // executed.) 8018086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen unsigned OrigBBSize = 0; 8028086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen for (MachineBasicBlock::iterator I = OrigBB->begin(), E = OrigBB->end(); 8038086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen I != E; ++I) 8048086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen OrigBBSize += TII->GetInstSizeInBytes(I); 805a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[OrigBBI].Size = OrigBBSize; 80699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 80799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // ...and adjust BBOffsets for NewBB accordingly. 8085bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen BBInfo[NewBBI].Offset = BBInfo[OrigBBI].postOffset(); 80999c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 8108086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // Figure out how large the NewMBB is. As the second half of the original 8118086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // block, it may contain a tablejump. 8128086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen unsigned NewBBSize = 0; 8138086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen for (MachineBasicBlock::iterator I = NewBB->begin(), E = NewBB->end(); 8148086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen I != E; ++I) 8158086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen NewBBSize += TII->GetInstSizeInBytes(I); 8168086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // Set the size of NewBB in BBSizes. It does not include any padding now. 817a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[NewBBI].Size = NewBBSize; 8188086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 8196fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen MachineInstr* ThumbJTMI = prior(NewBB->end()); 8206fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen if (ThumbJTMI->getOpcode() == ARM::tBR_JTr) { 8216fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // We've added another 2-byte instruction before this tablejump, which 8226fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // means we will always need padding if we didn't before, and vice versa. 8236fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen 8246fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // The original offset of the jump instruction was: 8255bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen unsigned OrigOffset = BBInfo[OrigBBI].postOffset() - delta; 8266fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen if (OrigOffset%4 == 0) { 8276fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // We had padding before and now we don't. No net change in code size. 8286fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen delta = 0; 8296fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen } else { 8306fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen // We didn't have padding before and now we do. 831a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[NewBBI].Size += 2; 8326fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen delta = 4; 8336fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen } 8346fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen } 8356fbea43b0b35e2a3f6f91a92edeffa873c5cd794Jakob Stoklund Olesen 83699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // All BBOffsets following these blocks must be modified. 8378086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen if (delta) 8388086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen AdjustBBOffsetsAfter(NewBB, delta); 8390c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng 8400c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng return NewBB; 841a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 842a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 8438593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// OffsetIsInRange - Checks whether UserOffset (the location of a constant pool 8448494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson/// reference) is within MaxDisp of TrialOffset (a proposed location of a 8458593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// constant pool entry). 8468494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilsonbool ARMConstantIslands::OffsetIsInRange(unsigned UserOffset, 847d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng unsigned TrialOffset, unsigned MaxDisp, 848d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool NegativeOK, bool IsSoImm) { 8498494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // On Thumb offsets==2 mod 4 are rounded down by the hardware for 8508494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // purposes of the displacement computation; compensate for that here. 8518593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Effectively, the valid range of displacements is 2 bytes smaller for such 8528593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // references. 85331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned TotalAdj = 0; 85431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb && UserOffset%4 !=0) { 8558593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen UserOffset -= 2; 85631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng TotalAdj = 2; 85731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 8588593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // CPEs will be rounded up to a multiple of 4. 85931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb && TrialOffset%4 != 0) { 8608593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen TrialOffset += 2; 86131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng TotalAdj += 2; 86231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 86331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 86431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // In Thumb2 mode, later branch adjustments can shift instructions up and 86531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // cause alignment change. In the worst case scenario this can cause the 86631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // user's effective address to be subtracted by 2 and the CPE's address to 86731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // be plus 2. 86831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb2 && TotalAdj != 4) 86931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng MaxDisp -= (4 - TotalAdj); 8708593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 87199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen if (UserOffset <= TrialOffset) { 87299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // User before the Trial. 873d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (TrialOffset - UserOffset <= MaxDisp) 874d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return true; 87540efc251cd7a52dd2375ec95ee38b1be4572178fEvan Cheng // FIXME: Make use full range of soimm values. 87699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen } else if (NegativeOK) { 877d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (UserOffset - TrialOffset <= MaxDisp) 878d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return true; 87940efc251cd7a52dd2375ec95ee38b1be4572178fEvan Cheng // FIXME: Make use full range of soimm values. 88099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen } 88199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen return false; 88299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen} 88399c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 88488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// WaterIsInRange - Returns true if a CPE placed after the specified 88588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// Water (a basic block) will be in range for the specific MI. 88688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 88788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesenbool ARMConstantIslands::WaterIsInRange(unsigned UserOffset, 8885d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng MachineBasicBlock* Water, CPUser &U) { 8895d9c4b60204d741c213456e21b87e9af6a3dc627Dale Johannesen unsigned MaxDisp = U.MaxDisp; 8905bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen unsigned CPEOffset = BBInfo[Water->getNumber()].postOffset(); 89188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 892d959aa421a8d14fc5aad29141f816db8f4362c7fDale Johannesen // If the CPE is to be inserted before the instruction, that will raise 893af4b7352193e4a024d4a4e87cac1ba1589e4de57Bob Wilson // the offset of the instruction. 894d959aa421a8d14fc5aad29141f816db8f4362c7fDale Johannesen if (CPEOffset < UserOffset) 8955d9c4b60204d741c213456e21b87e9af6a3dc627Dale Johannesen UserOffset += U.CPEMI->getOperand(2).getImm(); 896d959aa421a8d14fc5aad29141f816db8f4362c7fDale Johannesen 897d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return OffsetIsInRange(UserOffset, CPEOffset, MaxDisp, U.NegOk, U.IsSoImm); 89888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen} 89988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 90088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// CPEIsInRange - Returns true if the distance between specific MI and 901c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng/// specific ConstPool entry instruction can fit in MI's displacement field. 90288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesenbool ARMConstantIslands::CPEIsInRange(MachineInstr *MI, unsigned UserOffset, 9035d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng MachineInstr *CPEMI, unsigned MaxDisp, 9045d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool NegOk, bool DoDump) { 9058593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen unsigned CPEOffset = GetOffsetOf(CPEMI); 9064d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach assert((CPEOffset%4 == 0 || HasInlineAsm) && "Misaligned CPE"); 9072021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng 90888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (DoDump) { 909705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << "User of CPE#" << CPEMI->getOperand(0).getImm() 910705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " max delta=" << MaxDisp 911705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " insn address=" << UserOffset 912705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " CPE address=" << CPEOffset 913705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " offset=" << int(CPEOffset-UserOffset) << "\t" << *MI); 91488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 915a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 9165d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng return OffsetIsInRange(UserOffset, CPEOffset, MaxDisp, NegOk); 917c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng} 918c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng 919d1e7d9a88b5f4fa5e9a85affc4599c650c591ffbEvan Cheng#ifndef NDEBUG 920c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// BBIsJumpedOver - Return true of the specified basic block's only predecessor 921c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// unconditionally branches to its only successor. 922c99ef085b90b32952b484e8843fb66ad65215b61Evan Chengstatic bool BBIsJumpedOver(MachineBasicBlock *MBB) { 923c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng if (MBB->pred_size() != 1 || MBB->succ_size() != 1) 924c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return false; 925c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 926c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineBasicBlock *Succ = *MBB->succ_begin(); 927c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineBasicBlock *Pred = *MBB->pred_begin(); 928c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineInstr *PredMI = &Pred->back(); 9295e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin if (PredMI->getOpcode() == ARM::B || PredMI->getOpcode() == ARM::tB 9305e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin || PredMI->getOpcode() == ARM::t2B) 931c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return PredMI->getOperand(0).getMBB() == Succ; 932c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return false; 933c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng} 934d1e7d9a88b5f4fa5e9a85affc4599c650c591ffbEvan Cheng#endif // NDEBUG 935c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 9368494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilsonvoid ARMConstantIslands::AdjustBBOffsetsAfter(MachineBasicBlock *BB, 9378593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen int delta) { 9387896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineFunction::iterator MBBI = BB; MBBI = llvm::next(MBBI); 939d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng for(unsigned i = BB->getNumber()+1, e = BB->getParent()->getNumBlockIDs(); 940d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng i < e; ++i) { 941a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[i].Offset += delta; 9428593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // If some existing blocks have padding, adjust the padding as needed, a 9438593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // bit tricky. delta can be negative so don't use % on that. 944d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (!isThumb) 945d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng continue; 946d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MachineBasicBlock *MBB = MBBI; 9474d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach if (!MBB->empty() && !HasInlineAsm) { 948d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // Constant pool entries require padding. 949d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (MBB->begin()->getOpcode() == ARM::CONSTPOOL_ENTRY) { 950a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen unsigned OldOffset = BBInfo[i].Offset - delta; 951a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen if ((OldOffset%4) == 0 && (BBInfo[i].Offset%4) != 0) { 952d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // add new padding 953a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[i].Size += 2; 954d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta += 2; 955a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen } else if ((OldOffset%4) != 0 && (BBInfo[i].Offset%4) == 0) { 956d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // remove existing padding 957a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[i].Size -= 2; 958d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta -= 2; 9598593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 960d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng } 961d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // Thumb1 jump tables require padding. They should be at the end; 962d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // following unconditional branches are removed by AnalyzeBranch. 963b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng // tBR_JTr expands to a mov pc followed by .align 2 and then the jump 9648086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // table entries. So this code checks whether offset of tBR_JTr 9658086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // is aligned; if it is, the offset of the jump table following the 9668086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // instruction will not be aligned, and we need padding. 967789476240d6b6f8ad9366cadf790a82bd41bb0b3Evan Cheng MachineInstr *ThumbJTMI = prior(MBB->end()); 96866ac53165e17b7c76b8c69e57bde623d44ec492eEvan Cheng if (ThumbJTMI->getOpcode() == ARM::tBR_JTr) { 9698086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen unsigned NewMIOffset = GetOffsetOf(ThumbJTMI); 9704a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng unsigned OldMIOffset = NewMIOffset - delta; 9714a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng if ((OldMIOffset%4) == 0 && (NewMIOffset%4) != 0) { 972d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // remove existing padding 973a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[i].Size -= 2; 974d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta -= 2; 9754a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng } else if ((OldMIOffset%4) != 0 && (NewMIOffset%4) == 0) { 976d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // add new padding 977a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[i].Size += 2; 978d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta += 2; 9798593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 9808593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 981d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (delta==0) 982d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return; 9838593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 9847896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MBBI = llvm::next(MBBI); 9858593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 98699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen} 98799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 98888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// DecrementOldEntry - find the constant pool entry with index CPI 98988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// and instruction CPEMI, and decrement its refcount. If the refcount 9908494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson/// becomes 0 remove the entry and instruction. Returns true if we removed 99188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// the entry, false if we didn't. 992b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng 993ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Chengbool ARMConstantIslands::DecrementOldEntry(unsigned CPI, MachineInstr *CPEMI) { 994c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Find the old entry. Eliminate it if it is no longer used. 995ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng CPEntry *CPE = findConstPoolEntry(CPI, CPEMI); 996ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng assert(CPE && "Unexpected!"); 997ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (--CPE->RefCount == 0) { 998ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng RemoveDeadCPEMI(CPEMI); 999ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng CPE->CPEMI = NULL; 1000fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman --NumCPEs; 100188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return true; 100288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 100388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return false; 100488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen} 100588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 100688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// LookForCPEntryInRange - see if the currently referenced CPE is in range; 100788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// if not, see if an in-range clone of the CPE is in range, and if so, 100888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// change the data structures so the user references the clone. Returns: 100988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// 0 = no existing entry found 101088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// 1 = entry found, and there were no code insertions or deletions 101188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// 2 = entry found, and there were code insertions or deletions 101288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesenint ARMConstantIslands::LookForExistingCPEntry(CPUser& U, unsigned UserOffset) 101388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen{ 101488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen MachineInstr *UserMI = U.MI; 101588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen MachineInstr *CPEMI = U.CPEMI; 101688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 101788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Check to see if the CPE is already in-range. 10185d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng if (CPEIsInRange(UserMI, UserOffset, CPEMI, U.MaxDisp, U.NegOk, true)) { 1019893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "In range\n"); 102088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return 1; 1021c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng } 1022c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 102388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // No. Look for previously created clones of the CPE that are in range. 10248aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner unsigned CPI = CPEMI->getOperand(1).getIndex(); 102588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen std::vector<CPEntry> &CPEs = CPEntries[CPI]; 102688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen for (unsigned i = 0, e = CPEs.size(); i != e; ++i) { 102788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // We already tried this one 102888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (CPEs[i].CPEMI == CPEMI) 102988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen continue; 103088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Removing CPEs can leave empty entries, skip 103188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (CPEs[i].CPEMI == NULL) 103288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen continue; 10335d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng if (CPEIsInRange(UserMI, UserOffset, CPEs[i].CPEMI, U.MaxDisp, U.NegOk)) { 1034893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Replacing CPE#" << CPI << " with CPE#" 1035893e1c90a03a53cf13f73849324e83612688428aChris Lattner << CPEs[i].CPI << "\n"); 103688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Point the CPUser node to the replacement 103788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen U.CPEMI = CPEs[i].CPEMI; 103888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Change the CPI in the instruction operand to refer to the clone. 103988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen for (unsigned j = 0, e = UserMI->getNumOperands(); j != e; ++j) 1040d735b8019b0f297d7c14b55adcd887af24d8e602Dan Gohman if (UserMI->getOperand(j).isCPI()) { 10418aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner UserMI->getOperand(j).setIndex(CPEs[i].CPI); 104288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen break; 104388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 104488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Adjust the refcount of the clone... 104588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen CPEs[i].RefCount++; 104688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // ...and the original. If we didn't remove the old entry, none of the 104788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // addresses changed, so we don't need another pass. 1048ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng return DecrementOldEntry(CPI, CPEMI) ? 2 : 1; 104988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 105088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 105188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return 0; 105288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen} 105388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 1054f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen/// getUnconditionalBrDisp - Returns the maximum displacement that can fit in 1055f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen/// the specific unconditional branch instruction. 1056f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesenstatic inline unsigned getUnconditionalBrDisp(int Opc) { 10575e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin switch (Opc) { 10585e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::tB: 10595e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin return ((1<<10)-1)*2; 10605e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::t2B: 10615e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin return ((1<<23)-1)*2; 10625e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin default: 10635e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin break; 10645e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin } 1065764ab52dd80310a205c9888bf166d09dab858f90Jim Grosbach 10665e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin return ((1<<23)-1)*4; 1067f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen} 1068f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen 1069b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson/// LookForWater - Look for an existing entry in the WaterList in which 1070b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// we can place the CPE referenced from U so it's within range of U's MI. 1071b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson/// Returns true if found, false if not. If it returns true, WaterIter 1072f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// is set to the WaterList entry. For Thumb, prefer water that will not 1073f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// introduce padding to water that will. To ensure that this pass 1074f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// terminates, the CPE location for a particular CPUser is only allowed to 1075f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// move to a lower address, so search backward from the end of the list and 1076f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// prefer the first water that is in range. 1077b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesenbool ARMConstantIslands::LookForWater(CPUser &U, unsigned UserOffset, 1078b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson water_iterator &WaterIter) { 10793b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson if (WaterList.empty()) 10803b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson return false; 10813b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson 108232c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson bool FoundWaterThatWouldPad = false; 108332c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson water_iterator IPThatWouldPad; 10843b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson for (water_iterator IP = prior(WaterList.end()), 10853b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson B = WaterList.begin();; --IP) { 10863b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson MachineBasicBlock* WaterBB = *IP; 1087b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Check if water is in range and is either at a lower address than the 1088b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // current "high water mark" or a new water block that was created since 1089b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // the previous iteration by inserting an unconditional branch. In the 1090b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // latter case, we want to allow resetting the high water mark back to 1091b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // this new water since we haven't seen it before. Inserting branches 1092b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // should be relatively uncommon and when it does happen, we want to be 1093b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // sure to take advantage of it for all the CPEs near that block, so that 1094b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // we don't insert more branches than necessary. 1095b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (WaterIsInRange(UserOffset, WaterBB, U) && 1096b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson (WaterBB->getNumber() < U.HighWaterMark->getNumber() || 1097b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.count(WaterBB))) { 10983b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson unsigned WBBId = WaterBB->getNumber(); 10995bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen if (isThumb && BBInfo[WBBId].postOffset()%4 != 0) { 11003b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson // This is valid Water, but would introduce padding. Remember 11013b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson // it in case we don't find any Water that doesn't do this. 110232c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson if (!FoundWaterThatWouldPad) { 110332c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson FoundWaterThatWouldPad = true; 11043b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson IPThatWouldPad = IP; 1105f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 11063b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson } else { 1107b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterIter = IP; 11083b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson return true; 1109d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng } 111088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 11113b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson if (IP == B) 11123b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson break; 111388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 111432c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson if (FoundWaterThatWouldPad) { 1115b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterIter = IPThatWouldPad; 11168593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 11178593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 1118b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen return false; 1119b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen} 112088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 11218494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson/// CreateNewWater - No existing WaterList entry will work for 1122b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// CPUsers[CPUserIndex], so create a place to put the CPE. The end of the 1123b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// block is used if in range, and the conditional branch munged so control 1124b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// flow is correct. Otherwise the block is split to create a hole with an 1125757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson/// unconditional branch around it. In either case NewMBB is set to a 1126b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// block following which the new island can be inserted (the WaterList 1127b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// is not adjusted). 11288494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilsonvoid ARMConstantIslands::CreateNewWater(unsigned CPUserIndex, 1129757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson unsigned UserOffset, 1130757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson MachineBasicBlock *&NewMBB) { 1131b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUser &U = CPUsers[CPUserIndex]; 1132b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *UserMI = U.MI; 1133b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *CPEMI = U.CPEMI; 1134b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineBasicBlock *UserMBB = UserMI->getParent(); 11355bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen unsigned OffsetOfNextBlock = BBInfo[UserMBB->getNumber()].postOffset(); 11365bb32530bc1adb970eee2ac18508ea2876a2f410Jakob Stoklund Olesen assert(OffsetOfNextBlock == BBInfo[UserMBB->getNumber()+1].Offset); 1137b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 113836fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // If the block does not end in an unconditional branch already, and if the 113936fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // end of the block is within range, make new water there. (The addition 114036fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // below is for the unconditional branch we will be adding: 4 bytes on ARM + 114136fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // Thumb2, 2 on Thumb1. Possible Thumb1 alignment padding is allowed for 11428593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // inside OffsetIsInRange. 114336fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson if (BBHasFallthrough(UserMBB) && 1144d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng OffsetIsInRange(UserOffset, OffsetOfNextBlock + (isThumb1 ? 2: 4), 1145d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng U.MaxDisp, U.NegOk, U.IsSoImm)) { 1146893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Split at end of block\n"); 1147b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (&UserMBB->back() == UserMI) 1148b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen assert(BBHasFallthrough(UserMBB) && "Expected a fallthrough BB!"); 11497896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner NewMBB = llvm::next(MachineFunction::iterator(UserMBB)); 1150b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // Add an unconditional branch from UserMBB to fallthrough block. 1151b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // Record it for branch lengthening; this new branch will not get out of 1152b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // range, but if the preceding conditional branch is out of range, the 1153b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // targets will be exchanged, and the altered branch may be out of 1154b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // range, so the machinery has to know about it. 11555e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin int UncondBr = isThumb ? ((isThumb2) ? ARM::t2B : ARM::tB) : ARM::B; 115651f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson if (!isThumb) 115751f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(UserMBB, DebugLoc(), TII->get(UncondBr)).addMBB(NewMBB); 115851f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson else 115951f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(UserMBB, DebugLoc(), TII->get(UncondBr)).addMBB(NewMBB) 116051f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson .addImm(ARMCC::AL).addReg(0); 1161b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned MaxDisp = getUnconditionalBrDisp(UncondBr); 11628494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson ImmBranches.push_back(ImmBranch(&UserMBB->back(), 1163b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MaxDisp, false, UncondBr)); 1164d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng int delta = isThumb1 ? 2 : 4; 1165a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[UserMBB->getNumber()].Size += delta; 1166b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen AdjustBBOffsetsAfter(UserMBB, delta); 1167b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen } else { 1168b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // What a big block. Find a place within the block to split it. 1169d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // This is a little tricky on Thumb1 since instructions are 2 bytes 1170b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // and constant pool entries are 4 bytes: if instruction I references 1171b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // island CPE, and instruction I+1 references CPE', it will 1172b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // not work well to put CPE as far forward as possible, since then 1173b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // CPE' cannot immediately follow it (that location is 2 bytes 1174b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // farther away from I+1 than CPE was from I) and we'd need to create 11758593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // a new island. So, we make a first guess, then walk through the 11768593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // instructions between the one currently being looked at and the 11778593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // possible insertion point, and make sure any other instructions 11788593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // that reference CPEs will be able to use the same island area; 11798593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // if not, we back up the insertion point. 11808593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 1181b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // The 4 in the following is for the unconditional branch we'll be 1182d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // inserting (allows for long branch on Thumb1). Alignment of the 11838593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // island is handled inside OffsetIsInRange. 11848593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen unsigned BaseInsertOffset = UserOffset + U.MaxDisp -4; 1185b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // This could point off the end of the block if we've already got 1186b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // constant pool entries following this block; only the last one is 1187b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // in the water list. Back past any possible branches (allow for a 1188b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // conditional and a maximally long unconditional). 1189a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen if (BaseInsertOffset >= BBInfo[UserMBB->getNumber()+1].Offset) 1190a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BaseInsertOffset = BBInfo[UserMBB->getNumber()+1].Offset - 1191d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng (isThumb1 ? 6 : 8); 1192b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned EndInsertOffset = BaseInsertOffset + 1193b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPEMI->getOperand(2).getImm(); 1194b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineBasicBlock::iterator MI = UserMI; 1195b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen ++MI; 1196b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned CPUIndex = CPUserIndex+1; 1197719510a178a910feb1db707140011c32a30992c4Evan Cheng unsigned NumCPUsers = CPUsers.size(); 1198719510a178a910feb1db707140011c32a30992c4Evan Cheng MachineInstr *LastIT = 0; 119952e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray for (unsigned Offset = UserOffset+TII->GetInstSizeInBytes(UserMI); 1200b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen Offset < BaseInsertOffset; 120152e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray Offset += TII->GetInstSizeInBytes(MI), 1202719510a178a910feb1db707140011c32a30992c4Evan Cheng MI = llvm::next(MI)) { 1203719510a178a910feb1db707140011c32a30992c4Evan Cheng if (CPUIndex < NumCPUsers && CPUsers[CPUIndex].MI == MI) { 1204d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng CPUser &U = CPUsers[CPUIndex]; 12058494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson if (!OffsetIsInRange(Offset, EndInsertOffset, 1206d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng U.MaxDisp, U.NegOk, U.IsSoImm)) { 1207d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng BaseInsertOffset -= (isThumb1 ? 2 : 4); 1208d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng EndInsertOffset -= (isThumb1 ? 2 : 4); 1209f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 1210b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // This is overly conservative, as we don't account for CPEMIs 1211b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // being reused within the block, but it doesn't matter much. 1212b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen EndInsertOffset += CPUsers[CPUIndex].CPEMI->getOperand(2).getImm(); 1213b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUIndex++; 1214f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 1215719510a178a910feb1db707140011c32a30992c4Evan Cheng 1216719510a178a910feb1db707140011c32a30992c4Evan Cheng // Remember the last IT instruction. 1217719510a178a910feb1db707140011c32a30992c4Evan Cheng if (MI->getOpcode() == ARM::t2IT) 1218719510a178a910feb1db707140011c32a30992c4Evan Cheng LastIT = MI; 121988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 1220719510a178a910feb1db707140011c32a30992c4Evan Cheng 1221893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Split in middle of big block\n"); 1222719510a178a910feb1db707140011c32a30992c4Evan Cheng --MI; 1223719510a178a910feb1db707140011c32a30992c4Evan Cheng 1224719510a178a910feb1db707140011c32a30992c4Evan Cheng // Avoid splitting an IT block. 1225719510a178a910feb1db707140011c32a30992c4Evan Cheng if (LastIT) { 1226719510a178a910feb1db707140011c32a30992c4Evan Cheng unsigned PredReg = 0; 1227719510a178a910feb1db707140011c32a30992c4Evan Cheng ARMCC::CondCodes CC = llvm::getITInstrPredicate(MI, PredReg); 1228719510a178a910feb1db707140011c32a30992c4Evan Cheng if (CC != ARMCC::AL) 1229719510a178a910feb1db707140011c32a30992c4Evan Cheng MI = LastIT; 1230719510a178a910feb1db707140011c32a30992c4Evan Cheng } 1231719510a178a910feb1db707140011c32a30992c4Evan Cheng NewMBB = SplitBlockBeforeInstr(MI); 1232b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen } 1233b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen} 1234b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1235b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// HandleConstantPoolUser - Analyze the specified user, checking to see if it 123639bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson/// is out-of-range. If so, pick up the constant pool value and move it some 1237b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// place in-range. Return true if we changed any addresses (thus must run 1238b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// another pass of branch lengthening), false otherwise. 12395657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::HandleConstantPoolUser(MachineFunction &MF, 12408494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson unsigned CPUserIndex) { 1241b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUser &U = CPUsers[CPUserIndex]; 1242b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *UserMI = U.MI; 1243b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *CPEMI = U.CPEMI; 12448aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner unsigned CPI = CPEMI->getOperand(1).getIndex(); 1245b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned Size = CPEMI->getOperand(2).getImm(); 12468593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Compute this only once, it's expensive. The 4 or 8 is the value the 1247a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // hardware keeps in the PC. 1248b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned UserOffset = GetOffsetOf(UserMI) + (isThumb ? 4 : 8); 1249768c9f725bda048b3406b6289beb586ff6e933dfEvan Cheng 1250b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // See if the current entry is within range, or there is a clone of it 1251b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // in range. 1252b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen int result = LookForExistingCPEntry(U, UserOffset); 1253b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (result==1) return false; 1254b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen else if (result==2) return true; 1255b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1256b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // No existing clone of this CPE is within range. 1257b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // We will be generating a new clone. Get a UID for it. 12585de5d4b6d0eb3fd379fa571d82f6fa764460b3b8Evan Cheng unsigned ID = AFI->createPICLabelUId(); 1259b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1260f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson // Look for water where we can place this CPE. 1261b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *NewIsland = MF.CreateMachineBasicBlock(); 1262b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *NewMBB; 1263b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson water_iterator IP; 1264b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (LookForWater(U, UserOffset, IP)) { 1265b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson DEBUG(errs() << "found water in range\n"); 1266b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *WaterBB = *IP; 1267b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1268b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // If the original WaterList entry was "new water" on this iteration, 1269b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // propagate that to the new island. This is just keeping NewWaterList 1270b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // updated to match the WaterList, which will be updated below. 1271b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (NewWaterList.count(WaterBB)) { 1272b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.erase(WaterBB); 1273b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(NewIsland); 1274b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson } 1275b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // The new CPE goes before the following block (NewMBB). 12767896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner NewMBB = llvm::next(MachineFunction::iterator(WaterBB)); 1277b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1278b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson } else { 1279b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // No water found. 1280893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "No water found\n"); 1281757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson CreateNewWater(CPUserIndex, UserOffset, NewMBB); 1282b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1283b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // SplitBlockBeforeInstr adds to WaterList, which is important when it is 1284b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // called while handling branches so that the water will be seen on the 1285b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // next iteration for constant pools, but in this context, we don't want 1286b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // it. Check for this so it will be removed from the WaterList. 1287b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Also remove any entry from NewWaterList. 1288b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *WaterBB = prior(MachineFunction::iterator(NewMBB)); 1289b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson IP = std::find(WaterList.begin(), WaterList.end(), WaterBB); 1290b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (IP != WaterList.end()) 1291b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.erase(WaterBB); 1292b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1293b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // We are adding new water. Update NewWaterList. 1294b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(NewIsland); 129588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 129688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 1297b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Remove the original WaterList entry; we want subsequent insertions in 1298b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // this vicinity to go after the one we're about to insert. This 1299b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // considerably reduces the number of times we have to move the same CPE 1300b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // more than once and is also important to ensure the algorithm terminates. 1301b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (IP != WaterList.end()) 1302b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterList.erase(IP); 1303b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 130488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Okay, we know we can put an island before NewMBB now, do it! 13055657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.insert(NewMBB, NewIsland); 130688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 130788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Update internal data structures to account for the newly inserted MBB. 130888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen UpdateForInsertedWaterBlock(NewIsland); 130988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 131088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Decrement the old entry, and remove it if refcount becomes 0. 1311ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng DecrementOldEntry(CPI, CPEMI); 131288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 131388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Now that we have an island to add the CPE to, clone the original CPE and 131488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // add it to the island. 1315549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson U.HighWaterMark = NewIsland; 1316c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner U.CPEMI = BuildMI(NewIsland, DebugLoc(), TII->get(ARM::CONSTPOOL_ENTRY)) 1317a8e2989ece6dc46df59b0768184028257f913843Evan Cheng .addImm(ID).addConstantPoolIndex(CPI).addImm(Size); 131888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen CPEntries[CPI].push_back(CPEntry(U.CPEMI, ID, 1)); 1319fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCPEs; 1320c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 13213e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen // Mark the basic block as 4-byte aligned as required by the const-pool entry. 13223e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen NewIsland->setAlignment(2); 13233e572ac2fbdf6aa538500be07b9b050ac008669eJakob Stoklund Olesen 1324a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[NewIsland->getNumber()].Offset = BBInfo[NewMBB->getNumber()].Offset; 1325b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng // Compensate for .align 2 in thumb mode. 1326a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen if (isThumb && (BBInfo[NewIsland->getNumber()].Offset%4 != 0 || HasInlineAsm)) 13278593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen Size += 2; 1328a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Increase the size of the island block to account for the new entry. 1329a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[NewIsland->getNumber()].Size += Size; 133099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen AdjustBBOffsetsAfter(NewIsland, Size); 13318494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1332a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Finally, change the CPI in the instruction operand to be ID. 1333a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned i = 0, e = UserMI->getNumOperands(); i != e; ++i) 1334d735b8019b0f297d7c14b55adcd887af24d8e602Dan Gohman if (UserMI->getOperand(i).isCPI()) { 13358aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner UserMI->getOperand(i).setIndex(ID); 1336a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 1337a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 13388494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1339705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Moved CPE to #" << ID << " CPI=" << CPI 1340705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << '\t' << *UserMI); 13418494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1342a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return true; 1343a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 1344a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 1345ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// RemoveDeadCPEMI - Remove a dead constant pool entry instruction. Update 1346ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// sizes and offsets of impacted basic blocks. 1347ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Chengvoid ARMConstantIslands::RemoveDeadCPEMI(MachineInstr *CPEMI) { 1348ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng MachineBasicBlock *CPEBB = CPEMI->getParent(); 13498593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen unsigned Size = CPEMI->getOperand(2).getImm(); 13508593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen CPEMI->eraseFromParent(); 1351a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[CPEBB->getNumber()].Size -= Size; 13528593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // All succeeding offsets have the current size value added in, fix this. 1353ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (CPEBB->empty()) { 1354d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // In thumb1 mode, the size of island may be padded by two to compensate for 13558593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // the alignment requirement. Then it will now be 2 when the block is 1356ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng // empty, so fix this. 1357ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng // All succeeding offsets have the current size value added in, fix this. 1358a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen if (BBInfo[CPEBB->getNumber()].Size != 0) { 1359a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen Size += BBInfo[CPEBB->getNumber()].Size; 1360a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[CPEBB->getNumber()].Size = 0; 1361ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 1362305e5fe797cbba32d8091d687d47e98c8f3ee1f4Jakob Stoklund Olesen 1363305e5fe797cbba32d8091d687d47e98c8f3ee1f4Jakob Stoklund Olesen // This block no longer needs to be aligned. <rdar://problem/10534709>. 1364305e5fe797cbba32d8091d687d47e98c8f3ee1f4Jakob Stoklund Olesen CPEBB->setAlignment(0); 1365ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 13668593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen AdjustBBOffsetsAfter(CPEBB, -Size); 13678593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // An island has only one predecessor BB and one successor BB. Check if 13688593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // this BB's predecessor jumps directly to this BB's successor. This 13698593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // shouldn't happen currently. 13708593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen assert(!BBIsJumpedOver(CPEBB) && "How did this happen?"); 13718593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // FIXME: remove the empty blocks after all the work is done? 1372ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng} 1373ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 1374ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// RemoveUnusedCPEntries - Remove constant pool entries whose refcounts 1375ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// are zero. 1376ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Chengbool ARMConstantIslands::RemoveUnusedCPEntries() { 1377ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng unsigned MadeChange = false; 1378ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng for (unsigned i = 0, e = CPEntries.size(); i != e; ++i) { 1379ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng std::vector<CPEntry> &CPEs = CPEntries[i]; 1380ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng for (unsigned j = 0, ee = CPEs.size(); j != ee; ++j) { 1381ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (CPEs[j].RefCount == 0 && CPEs[j].CPEMI) { 1382ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng RemoveDeadCPEMI(CPEs[j].CPEMI); 1383ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng CPEs[j].CPEMI = NULL; 1384ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng MadeChange = true; 1385ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 1386ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 13878494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson } 1388ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng return MadeChange; 1389ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng} 1390ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 139188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// BBIsInRange - Returns true if the distance between specific MI and 139243aeab68a69e443c528092b4424a498d813f96b7Evan Cheng/// specific BB can fit in MI's displacement field. 1393c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Chengbool ARMConstantIslands::BBIsInRange(MachineInstr *MI,MachineBasicBlock *DestBB, 1394c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng unsigned MaxDisp) { 1395b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned PCAdj = isThumb ? 4 : 8; 1396c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng unsigned BrOffset = GetOffsetOf(MI) + PCAdj; 1397a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen unsigned DestOffset = BBInfo[DestBB->getNumber()].Offset; 139843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1399705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << "Branch of destination BB#" << DestBB->getNumber() 1400705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " from BB#" << MI->getParent()->getNumber() 1401705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " max delta=" << MaxDisp 1402705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " from " << GetOffsetOf(MI) << " to " << DestOffset 1403705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " offset " << int(DestOffset-BrOffset) << "\t" << *MI); 1404c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng 14058593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (BrOffset <= DestOffset) { 14068593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Branch before the Dest. 14078593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (DestOffset-BrOffset <= MaxDisp) 14088593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 14098593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } else { 14108593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (BrOffset-DestOffset <= MaxDisp) 14118593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 14128593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 14138593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return false; 141443aeab68a69e443c528092b4424a498d813f96b7Evan Cheng} 141543aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1416d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// FixUpImmediateBr - Fix up an immediate branch whose destination is too far 1417d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// away to fit in its displacement field. 14185657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::FixUpImmediateBr(MachineFunction &MF, ImmBranch &Br) { 1419d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = Br.MI; 14208aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *DestBB = MI->getOperand(0).getMBB(); 1421d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1422c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng // Check to see if the DestBB is already in-range. 1423c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng if (BBIsInRange(MI, DestBB, Br.MaxDisp)) 1424d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return false; 1425d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1426d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng if (!Br.isCond) 14275657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return FixUpUnconditionalBr(MF, Br); 14285657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return FixUpConditionalBr(MF, Br); 1429d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 1430d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 143188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// FixUpUnconditionalBr - Fix up an unconditional branch whose destination is 143288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// too far away to fit in its displacement field. If the LR register has been 1433d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// spilled in the epilogue, then we can use BL to implement a far jump. 143439bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson/// Otherwise, add an intermediate branch instruction to a branch. 1435d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Chengbool 14365657c01949dca6c012ac60d242d1a8d2ffdf5603Evan ChengARMConstantIslands::FixUpUnconditionalBr(MachineFunction &MF, ImmBranch &Br) { 1437d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = Br.MI; 1438d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineBasicBlock *MBB = MI->getParent(); 143953c67c0218d8420234dd71bf2d9df3388909af77Evan Cheng if (!isThumb1) 144053c67c0218d8420234dd71bf2d9df3388909af77Evan Cheng llvm_unreachable("FixUpUnconditionalBr is Thumb1 only!"); 1441d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1442d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // Use BL to implement far jump. 1443d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng Br.MaxDisp = (1 << 21) * 2; 14445080f4d9919d39b367891dc51e739c571a66036cChris Lattner MI->setDesc(TII->get(ARM::tBfar)); 1445a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size += 2; 144699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen AdjustBBOffsetsAfter(MBB, 2); 1447d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng HasFarJump = true; 1448fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumUBrFixed; 1449bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng 1450705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Changed B to long jump " << *MI); 1451bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng 1452d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return true; 1453d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 1454d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 145588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// FixUpConditionalBr - Fix up a conditional branch whose destination is too 1456d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// far away to fit in its displacement field. It is converted to an inverse 1457d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// conditional branch + an unconditional branch to the destination. 1458af5cbcb809bdbd30ebacab942994721c134d16a2Evan Chengbool 14595657c01949dca6c012ac60d242d1a8d2ffdf5603Evan ChengARMConstantIslands::FixUpConditionalBr(MachineFunction &MF, ImmBranch &Br) { 1460af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MachineInstr *MI = Br.MI; 14618aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *DestBB = MI->getOperand(0).getMBB(); 1462af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 146339bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // Add an unconditional branch to the destination and invert the branch 1464d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // condition to jump over it: 1465af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // blt L1 1466af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // => 1467af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // bge L2 1468af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // b L1 1469af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // L2: 14709a1ceaedc282f0cae31f2723f4d6c00c7b88fe90Chris Lattner ARMCC::CondCodes CC = (ARMCC::CondCodes)MI->getOperand(1).getImm(); 1471af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng CC = ARMCC::getOppositeCondition(CC); 14720e1d37904abbf7e8c4c478408253dd995f3040f4Evan Cheng unsigned CCReg = MI->getOperand(2).getReg(); 1473af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 1474af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // If the branch is at the end of its MBB and that has a fall-through block, 1475af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // direct the updated conditional branch to the fall-through block. Otherwise, 1476af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // split the MBB before the next instruction. 1477af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 1478bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng MachineInstr *BMI = &MBB->back(); 1479bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng bool NeedSplit = (BMI != MI) || !BBHasFallthrough(MBB); 148043aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1481fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCBrFixed; 1482bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng if (BMI != MI) { 14837896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner if (llvm::next(MachineBasicBlock::iterator(MI)) == prior(MBB->end()) && 1484bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng BMI->getOpcode() == Br.UncondBr) { 148539bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // Last MI in the BB is an unconditional branch. Can we simply invert the 148643aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // condition and swap destinations: 148743aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // beq L1 148843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // b L2 148943aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // => 149043aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // bne L2 149143aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // b L1 14928aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *NewDest = BMI->getOperand(0).getMBB(); 1493c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng if (BBIsInRange(MI, NewDest, Br.MaxDisp)) { 1494705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Invert Bcc condition and swap its destination with " 1495705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << *BMI); 14968aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner BMI->getOperand(0).setMBB(DestBB); 14978aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MI->getOperand(0).setMBB(NewDest); 149843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng MI->getOperand(1).setImm(CC); 149943aeab68a69e443c528092b4424a498d813f96b7Evan Cheng return true; 150043aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 150143aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 150243aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 150343aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 150443aeab68a69e443c528092b4424a498d813f96b7Evan Cheng if (NeedSplit) { 1505af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng SplitBlockBeforeInstr(MI); 150639bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // No need for the branch to the next block. We're adding an unconditional 1507dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng // branch to the destination. 150852e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray int delta = TII->GetInstSizeInBytes(&MBB->back()); 1509a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size -= delta; 15107896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineBasicBlock* SplitBB = llvm::next(MachineFunction::iterator(MBB)); 15118593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen AdjustBBOffsetsAfter(SplitBB, -delta); 1512dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng MBB->back().eraseFromParent(); 1513a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen // BBInfo[SplitBB].Offset is wrong temporarily, fixed below 1514dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng } 15157896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineBasicBlock *NextBB = llvm::next(MachineFunction::iterator(MBB)); 15168494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1517893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << " Insert B to BB#" << DestBB->getNumber() 1518893e1c90a03a53cf13f73849324e83612688428aChris Lattner << " also invert condition and change dest. to BB#" 1519893e1c90a03a53cf13f73849324e83612688428aChris Lattner << NextBB->getNumber() << "\n"); 1520af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 152156c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen // Insert a new conditional branch and a new unconditional branch. 1522af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // Also update the ImmBranch as well as adding a new entry for the new branch. 1523c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(MBB, DebugLoc(), TII->get(MI->getOpcode())) 1524b67284057ee130114055309eabe0bcd1af13777dDale Johannesen .addMBB(NextBB).addImm(CC).addReg(CCReg); 1525af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Br.MI = &MBB->back(); 1526a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size += TII->GetInstSizeInBytes(&MBB->back()); 1527cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson if (isThumb) 1528cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson BuildMI(MBB, DebugLoc(), TII->get(Br.UncondBr)).addMBB(DestBB) 1529cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson .addImm(ARMCC::AL).addReg(0); 1530cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson else 1531cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson BuildMI(MBB, DebugLoc(), TII->get(Br.UncondBr)).addMBB(DestBB); 1532a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size += TII->GetInstSizeInBytes(&MBB->back()); 1533a9b8b8d62c67e96bc4dc2ed25298c539102f8638Evan Cheng unsigned MaxDisp = getUnconditionalBrDisp(Br.UncondBr); 1534a0bf794eb60b6795a121efcb9ff759e9e0955772Evan Cheng ImmBranches.push_back(ImmBranch(&MBB->back(), MaxDisp, false, Br.UncondBr)); 153556c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen 153656c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen // Remove the old conditional branch. It may or may not still be in MBB. 1537a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MI->getParent()->getNumber()].Size -= TII->GetInstSizeInBytes(MI); 1538af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MI->eraseFromParent(); 1539af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 154056c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen // The net size change is an addition of one unconditional branch. 154152e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray int delta = TII->GetInstSizeInBytes(&MBB->back()); 154299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen AdjustBBOffsetsAfter(MBB, delta); 1543af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng return true; 1544af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng} 1545d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1546d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// UndoLRSpillRestore - Remove Thumb push / pop instructions that only spills 15474b322e58b77d16f103d88a3af3a4ebd2675245a0Evan Cheng/// LR / restores LR to pc. FIXME: This is done here because it's only possible 15484b322e58b77d16f103d88a3af3a4ebd2675245a0Evan Cheng/// to do this if tBfar is not used. 1549d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Chengbool ARMConstantIslands::UndoLRSpillRestore() { 1550d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng bool MadeChange = false; 1551d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng for (unsigned i = 0, e = PushPopMIs.size(); i != e; ++i) { 1552d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = PushPopMIs[i]; 1553815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson // First two operands are predicates. 155444bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng if (MI->getOpcode() == ARM::tPOP_RET && 1555815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson MI->getOperand(2).getReg() == ARM::PC && 1556815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson MI->getNumExplicitOperands() == 3) { 155725e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach // Create the new insn and copy the predicate from the old. 155825e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach BuildMI(MI->getParent(), MI->getDebugLoc(), TII->get(ARM::tBX_RET)) 155925e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach .addOperand(MI->getOperand(0)) 156025e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach .addOperand(MI->getOperand(1)); 156144bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng MI->eraseFromParent(); 156244bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng MadeChange = true; 1563d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng } 1564d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng } 1565d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return MadeChange; 1566d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 15675657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 1568a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Chengbool ARMConstantIslands::OptimizeThumb2Instructions(MachineFunction &MF) { 1569a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng bool MadeChange = false; 1570a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1571a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // Shrink ADR and LDR from constantpool. 1572a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng for (unsigned i = 0, e = CPUsers.size(); i != e; ++i) { 1573a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng CPUser &U = CPUsers[i]; 1574a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Opcode = U.MI->getOpcode(); 1575a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned NewOpc = 0; 1576a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Scale = 1; 1577a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Bits = 0; 1578a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng switch (Opcode) { 1579a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng default: break; 15806b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson case ARM::t2LEApcrel: 1581a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (isARMLowRegister(U.MI->getOperand(0).getReg())) { 1582a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng NewOpc = ARM::tLEApcrel; 1583a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Bits = 8; 1584a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Scale = 4; 1585a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1586a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng break; 1587a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng case ARM::t2LDRpci: 1588a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (isARMLowRegister(U.MI->getOperand(0).getReg())) { 1589a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng NewOpc = ARM::tLDRpci; 1590a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Bits = 8; 1591a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Scale = 4; 1592a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1593a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng break; 1594a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1595a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1596a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (!NewOpc) 1597a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng continue; 1598a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1599a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned UserOffset = GetOffsetOf(U.MI) + 4; 1600a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned MaxOffs = ((1 << Bits) - 1) * Scale; 1601a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // FIXME: Check if offset is multiple of scale if scale is not 4. 1602a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (CPEIsInRange(U.MI, UserOffset, U.CPEMI, MaxOffs, false, true)) { 1603a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng U.MI->setDesc(TII->get(NewOpc)); 1604a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MachineBasicBlock *MBB = U.MI->getParent(); 1605a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size -= 2; 1606a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng AdjustBBOffsetsAfter(MBB, -2); 1607a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng ++NumT2CPShrunk; 1608a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MadeChange = true; 1609a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1610a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1611a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1612a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MadeChange |= OptimizeThumb2Branches(MF); 161301dec0e545de18aadcd3911563a93d10a625be80Jim Grosbach MadeChange |= OptimizeThumb2JumpTables(MF); 1614a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng return MadeChange; 1615a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng} 1616a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1617a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Chengbool ARMConstantIslands::OptimizeThumb2Branches(MachineFunction &MF) { 161831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng bool MadeChange = false; 161931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 162031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng for (unsigned i = 0, e = ImmBranches.size(); i != e; ++i) { 162131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng ImmBranch &Br = ImmBranches[i]; 162231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Opcode = Br.MI->getOpcode(); 162331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned NewOpc = 0; 162431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Scale = 1; 162531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Bits = 0; 162631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng switch (Opcode) { 162731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng default: break; 162831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng case ARM::t2B: 162931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng NewOpc = ARM::tB; 163031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Bits = 11; 163131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Scale = 2; 163231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng break; 1633de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng case ARM::t2Bcc: { 163431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng NewOpc = ARM::tBcc; 163531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Bits = 8; 1636de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Scale = 2; 163731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng break; 163831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 1639de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1640de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (NewOpc) { 1641de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned MaxOffs = ((1 << (Bits-1))-1) * Scale; 1642de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MachineBasicBlock *DestBB = Br.MI->getOperand(0).getMBB(); 1643de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (BBIsInRange(Br.MI, DestBB, MaxOffs)) { 1644de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Br.MI->setDesc(TII->get(NewOpc)); 1645de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MachineBasicBlock *MBB = Br.MI->getParent(); 1646a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size -= 2; 1647de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng AdjustBBOffsetsAfter(MBB, -2); 1648de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng ++NumT2BrShrunk; 1649de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MadeChange = true; 1650de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1651de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1652de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng 1653de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Opcode = Br.MI->getOpcode(); 1654de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (Opcode != ARM::tBcc) 165531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng continue; 165631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 1657de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = 0; 1658de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned PredReg = 0; 1659de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng ARMCC::CondCodes Pred = llvm::getInstrPredicate(Br.MI, PredReg); 1660de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (Pred == ARMCC::EQ) 1661de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = ARM::tCBZ; 1662de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng else if (Pred == ARMCC::NE) 1663de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = ARM::tCBNZ; 1664de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (!NewOpc) 1665de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng continue; 166631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng MachineBasicBlock *DestBB = Br.MI->getOperand(0).getMBB(); 1667de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng // Check if the distance is within 126. Subtract starting offset by 2 1668de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng // because the cmp will be eliminated. 1669de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned BrOffset = GetOffsetOf(Br.MI) + 4 - 2; 1670a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen unsigned DestOffset = BBInfo[DestBB->getNumber()].Offset; 1671de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (BrOffset < DestOffset && (DestOffset - BrOffset) <= 126) { 16720539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MachineBasicBlock::iterator CmpMI = Br.MI; 16730539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng if (CmpMI != Br.MI->getParent()->begin()) { 16740539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng --CmpMI; 16750539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng if (CmpMI->getOpcode() == ARM::tCMPi8) { 16760539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng unsigned Reg = CmpMI->getOperand(0).getReg(); 16770539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng Pred = llvm::getInstrPredicate(CmpMI, PredReg); 16780539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng if (Pred == ARMCC::AL && 16790539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng CmpMI->getOperand(1).getImm() == 0 && 16800539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng isARMLowRegister(Reg)) { 16810539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MachineBasicBlock *MBB = Br.MI->getParent(); 16820539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MachineInstr *NewBR = 16830539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng BuildMI(*MBB, CmpMI, Br.MI->getDebugLoc(), TII->get(NewOpc)) 16840539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng .addReg(Reg).addMBB(DestBB,Br.MI->getOperand(0).getTargetFlags()); 16850539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng CmpMI->eraseFromParent(); 16860539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng Br.MI->eraseFromParent(); 16870539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng Br.MI = NewBR; 1688a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size -= 2; 16890539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng AdjustBBOffsetsAfter(MBB, -2); 16900539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng ++NumCBZ; 16910539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MadeChange = true; 16920539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng } 1693de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1694de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 169531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 169631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 169731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 169831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng return MadeChange; 1699a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng} 1700a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1701a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng/// OptimizeThumb2JumpTables - Use tbb / tbh instructions to generate smaller 1702a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng/// jumptables when it's possible. 17035657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::OptimizeThumb2JumpTables(MachineFunction &MF) { 17045657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool MadeChange = false; 17055657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17065657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng // FIXME: After the tables are shrunk, can we get rid some of the 17075657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng // constantpool tables? 17081fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineJumpTableInfo *MJTI = MF.getJumpTableInfo(); 1709b1e803985d3378538ae9cff7eed4102c002d1e22Chris Lattner if (MJTI == 0) return false; 171026b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach 17115657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 17125657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned i = 0, e = T2JumpTables.size(); i != e; ++i) { 17135657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineInstr *MI = T2JumpTables[i]; 1714e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng const MCInstrDesc &MCID = MI->getDesc(); 1715e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng unsigned NumOps = MCID.getNumOperands(); 1716e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng unsigned JTOpIdx = NumOps - (MCID.isPredicable() ? 3 : 2); 17175657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineOperand JTOP = MI->getOperand(JTOpIdx); 17185657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned JTI = JTOP.getIndex(); 17195657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng assert(JTI < JT.size()); 17205657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17211fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach bool ByteOk = true; 17221fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach bool HalfWordOk = true; 172380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach unsigned JTOffset = GetOffsetOf(MI) + 4; 172480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 17255657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned j = 0, ee = JTBBs.size(); j != ee; ++j) { 17265657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *MBB = JTBBs[j]; 1727a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen unsigned DstOffset = BBInfo[MBB->getNumber()].Offset; 17288770f747a98194056805f1b7cbcb0b75a7633b87Evan Cheng // Negative offset is not ok. FIXME: We should change BB layout to make 17298770f747a98194056805f1b7cbcb0b75a7633b87Evan Cheng // sure all the branches are forward. 1730d26b14c34cbcee1448b86b524578fc51cc979023Evan Cheng if (ByteOk && (DstOffset - JTOffset) > ((1<<8)-1)*2) 17315657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng ByteOk = false; 173225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned TBHLimit = ((1<<16)-1)*2; 173325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng if (HalfWordOk && (DstOffset - JTOffset) > TBHLimit) 17345657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng HalfWordOk = false; 17355657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!ByteOk && !HalfWordOk) 17365657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 17375657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17385657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17395657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (ByteOk || HalfWordOk) { 17405657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 17415657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned BaseReg = MI->getOperand(0).getReg(); 17425657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool BaseRegKill = MI->getOperand(0).isKill(); 17435657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!BaseRegKill) 17445657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17455657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned IdxReg = MI->getOperand(1).getReg(); 17465657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool IdxRegKill = MI->getOperand(1).isKill(); 1747c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 1748c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // Scan backwards to find the instruction that defines the base 1749c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // register. Due to post-RA scheduling, we can't count on it 1750c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // immediately preceding the branch instruction. 17515657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock::iterator PrevI = MI; 1752c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineBasicBlock::iterator B = MBB->begin(); 1753c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach while (PrevI != B && !PrevI->definesRegister(BaseReg)) 1754c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach --PrevI; 1755c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 1756c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // If for some reason we didn't find it, we can't do anything, so 1757c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // just skip this one. 1758c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach if (!PrevI->definesRegister(BaseReg)) 17595657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17605657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 1761c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineInstr *AddrMI = PrevI; 17625657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool OptOk = true; 176326b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach // Examine the instruction that calculates the jumptable entry address. 1764c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // Make sure it only defines the base register and kills any uses 1765c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // other than the index register. 17665657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned k = 0, eee = AddrMI->getNumOperands(); k != eee; ++k) { 17675657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const MachineOperand &MO = AddrMI->getOperand(k); 17685657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!MO.isReg() || !MO.getReg()) 17695657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17705657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (MO.isDef() && MO.getReg() != BaseReg) { 17715657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng OptOk = false; 17725657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 17735657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17745657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (MO.isUse() && !MO.isKill() && MO.getReg() != IdxReg) { 17755657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng OptOk = false; 17765657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 17775657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17785657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17795657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!OptOk) 17805657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17815657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17826b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson // Now scan back again to find the tLEApcrel or t2LEApcrelJT instruction 1783c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // that gave us the initial base register definition. 1784c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach for (--PrevI; PrevI != B && !PrevI->definesRegister(BaseReg); --PrevI) 1785c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach ; 1786c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 17876b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson // The instruction should be a tLEApcrel or t2LEApcrelJT; we want 1788a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // to delete it as well. 1789c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineInstr *LeaMI = PrevI; 1790a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if ((LeaMI->getOpcode() != ARM::tLEApcrelJT && 17916b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson LeaMI->getOpcode() != ARM::t2LEApcrelJT) || 17925657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng LeaMI->getOperand(0).getReg() != BaseReg) 179325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OptOk = false; 179425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 179525f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng if (!OptOk) 179625f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng continue; 179725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 1798d092a87ba3f905a6801a0bdf816267329cf0391cJim Grosbach unsigned Opc = ByteOk ? ARM::t2TBB_JT : ARM::t2TBH_JT; 179925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MachineInstr *NewJTMI = BuildMI(MBB, MI->getDebugLoc(), TII->get(Opc)) 180025f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addReg(IdxReg, getKillRegState(IdxRegKill)) 180125f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addJumpTableIndex(JTI, JTOP.getTargetFlags()) 180225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addImm(MI->getOperand(JTOpIdx+1).getImm()); 180325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng // FIXME: Insert an "ALIGN" instruction to ensure the next instruction 180425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng // is 2-byte aligned. For now, asm printer will fix it up. 180525f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned NewSize = TII->GetInstSizeInBytes(NewJTMI); 180625f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned OrigSize = TII->GetInstSizeInBytes(AddrMI); 180725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OrigSize += TII->GetInstSizeInBytes(LeaMI); 180825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OrigSize += TII->GetInstSizeInBytes(MI); 180925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 181025f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng AddrMI->eraseFromParent(); 181125f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng LeaMI->eraseFromParent(); 181225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MI->eraseFromParent(); 181325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 181425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng int delta = OrigSize - NewSize; 1815a3f331bd81f9d468654635df4428ecc8d8ebb5eaJakob Stoklund Olesen BBInfo[MBB->getNumber()].Size -= delta; 181625f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng AdjustBBOffsetsAfter(MBB, -delta); 181725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 181825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng ++NumTBs; 181925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MadeChange = true; 18205657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 18215657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 18225657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 18235657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return MadeChange; 18245657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng} 18251fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 18269249efe4c7451e83fb4c904fd7fcc8edfe08d815Jim Grosbach/// ReorderThumb2JumpTables - Adjust the function's block layout to ensure that 18279249efe4c7451e83fb4c904fd7fcc8edfe08d815Jim Grosbach/// jump tables always branch forwards, since that's what tbb and tbh need. 182880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbachbool ARMConstantIslands::ReorderThumb2JumpTables(MachineFunction &MF) { 182980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach bool MadeChange = false; 183080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 183180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineJumpTableInfo *MJTI = MF.getJumpTableInfo(); 1832b1e803985d3378538ae9cff7eed4102c002d1e22Chris Lattner if (MJTI == 0) return false; 183326b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach 183480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 183580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (unsigned i = 0, e = T2JumpTables.size(); i != e; ++i) { 183680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineInstr *MI = T2JumpTables[i]; 1837e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng const MCInstrDesc &MCID = MI->getDesc(); 1838e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng unsigned NumOps = MCID.getNumOperands(); 1839e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng unsigned JTOpIdx = NumOps - (MCID.isPredicable() ? 3 : 2); 184080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineOperand JTOP = MI->getOperand(JTOpIdx); 184180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach unsigned JTI = JTOP.getIndex(); 184280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach assert(JTI < JT.size()); 184380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 184480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // We prefer if target blocks for the jump table come after the jump 184580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // instruction so we can use TB[BH]. Loop through the target blocks 184680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // and try to adjust them such that that's true. 184708cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach int JTNumber = MI->getParent()->getNumber(); 184880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 184980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (unsigned j = 0, ee = JTBBs.size(); j != ee; ++j) { 185080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *MBB = JTBBs[j]; 185108cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach int DTNumber = MBB->getNumber(); 185280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 185308cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach if (DTNumber < JTNumber) { 185480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // The destination precedes the switch. Try to move the block forward 185580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // so we have a positive offset. 185680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *NewBB = 185780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach AdjustJTTargetBlockForward(MBB, MI->getParent()); 185880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach if (NewBB) 185900a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach MJTI->ReplaceMBBInJumpTable(JTI, JTBBs[j], NewBB); 186080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MadeChange = true; 186180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 186280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 186380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 186480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 186580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach return MadeChange; 186680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach} 186780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 18681fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim GrosbachMachineBasicBlock *ARMConstantIslands:: 18691fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim GrosbachAdjustJTTargetBlockForward(MachineBasicBlock *BB, MachineBasicBlock *JTBB) 18701fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach{ 18711fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineFunction &MF = *BB->getParent(); 18721fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 187303e2d44722c1ebd3953007db0579147b46efba18Jim Grosbach // If the destination block is terminated by an unconditional branch, 187480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // try to move it; otherwise, create a new block following the jump 187508cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // table that branches back to the actual target. This is a very simple 187608cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // heuristic. FIXME: We can definitely improve it. 187780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *TBB = 0, *FBB = 0; 187880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach SmallVector<MachineOperand, 4> Cond; 1879a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach SmallVector<MachineOperand, 4> CondPrior; 1880a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MachineFunction::iterator BBi = BB; 1881a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MachineFunction::iterator OldPrior = prior(BBi); 188200a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach 1883ca215e7804ca5d85e19e31850c3ba3d155624e89Jim Grosbach // If the block terminator isn't analyzable, don't try to move the block 1884a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach bool B = TII->AnalyzeBranch(*BB, TBB, FBB, Cond); 1885ca215e7804ca5d85e19e31850c3ba3d155624e89Jim Grosbach 1886a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach // If the block ends in an unconditional branch, move it. The prior block 1887a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach // has to have an analyzable terminator for us to move this one. Be paranoid 188808cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // and make sure we're not trying to move the entry block of the function. 1889a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach if (!B && Cond.empty() && BB != MF.begin() && 1890a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach !TII->AnalyzeBranch(*OldPrior, TBB, FBB, CondPrior)) { 189180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach BB->moveAfter(JTBB); 189280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach OldPrior->updateTerminator(); 189300a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach BB->updateTerminator(); 189408cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // Update numbering to account for the block being moved. 1895a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MF.RenumberBlocks(); 189680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach ++NumJTMoved; 189780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach return NULL; 189880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 18991fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 19001fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Create a new MBB for the code after the jump BB. 19011fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineBasicBlock *NewBB = 19021fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MF.CreateMachineBasicBlock(JTBB->getBasicBlock()); 19031fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineFunction::iterator MBBI = JTBB; ++MBBI; 19041fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MF.insert(MBBI, NewBB); 19051fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 19061fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Add an unconditional branch from NewBB to BB. 19071fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // There doesn't seem to be meaningful DebugInfo available; this doesn't 19081fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // correspond directly to anything in the source. 19091fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach assert (isThumb2 && "Adjusting for TB[BH] but not in Thumb2?"); 191051f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(NewBB, DebugLoc(), TII->get(ARM::t2B)).addMBB(BB) 191151f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson .addImm(ARMCC::AL).addReg(0); 19121fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 191300a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach // Update internal data structures to account for the newly inserted MBB. 191400a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach MF.RenumberBlocks(NewBB); 191500a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach 19161fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Update the CFG. 19171fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach NewBB->addSuccessor(BB); 19181fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach JTBB->removeSuccessor(BB); 19191fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach JTBB->addSuccessor(NewBB); 19201fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 192180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach ++NumJTInserted; 19221fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach return NewBB; 19231fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach} 1924