ARMConstantIslandPass.cpp revision cd4338fff5cc9427003766519bebcfa213b32d61
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 { 67a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// BBSizes - The size of each MachineBasicBlock in bytes of code, indexed 688593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen /// by MBB Number. The two-byte pads required for Thumb alignment are 698593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen /// counted as part of the following block (i.e., the offset and size for 708593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen /// a padded block will both be ==2 mod 4). 71e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<unsigned> BBSizes; 728494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 7399c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen /// BBOffsets - the offset of each MBB in bytes, starting from 0. 748593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen /// The two-byte pads required for Thumb alignment are counted as part of 758593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen /// the following block. 7699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen std::vector<unsigned> BBOffsets; 7799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 78a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// WaterList - A sorted list of basic blocks where islands could be placed 79a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// (i.e. blocks that don't fall through to the following block, due 80a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// to a return, unreachable, or unconditional branch). 81e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<MachineBasicBlock*> WaterList; 82c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 83b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson /// NewWaterList - The subset of WaterList that was created since the 84b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson /// previous iteration by inserting unconditional branches. 85b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson SmallSet<MachineBasicBlock*, 4> NewWaterList; 86b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 87034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson typedef std::vector<MachineBasicBlock*>::iterator water_iterator; 88034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson 89a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// CPUser - One user of a constant pool, keeping the machine instruction 90a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// pointer, the constant pool being referenced, and the max displacement 91549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// allowed from the instruction to the CP. The HighWaterMark records the 92549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// highest basic block where a new CPEntry can be placed. To ensure this 93549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// pass terminates, the CP entries are initially placed at the end of the 94549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// function and then move monotonically to lower addresses. The 95549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// exception to this rule is when the current CP entry for a particular 96549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// CPUser is out of range, but there is another CP entry for the same 97549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// constant value in range. We want to use the existing in-range CP 98549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// entry, but if it later moves out of range, the search for new water 99549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// should resume where it left off. The HighWaterMark is used to record 100549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson /// that point. 101a8e2989ece6dc46df59b0768184028257f913843Evan Cheng struct CPUser { 102a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineInstr *MI; 103a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineInstr *CPEMI; 104549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson MachineBasicBlock *HighWaterMark; 105a8e2989ece6dc46df59b0768184028257f913843Evan Cheng unsigned MaxDisp; 1065d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool NegOk; 107d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool IsSoImm; 108d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng CPUser(MachineInstr *mi, MachineInstr *cpemi, unsigned maxdisp, 109d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool neg, bool soimm) 110549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson : MI(mi), CPEMI(cpemi), MaxDisp(maxdisp), NegOk(neg), IsSoImm(soimm) { 111549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson HighWaterMark = CPEMI->getParent(); 112549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson } 113a8e2989ece6dc46df59b0768184028257f913843Evan Cheng }; 1148494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 115a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// CPUsers - Keep track of all of the machine instructions that use various 116a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// constant pools and their max displacement. 117e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<CPUser> CPUsers; 1188494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 119c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// CPEntry - One per constant pool entry, keeping the machine instruction 120c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// pointer, the constpool index, and the number of CPUser's which 121c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// reference this entry. 122c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng struct CPEntry { 123c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineInstr *CPEMI; 124c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng unsigned CPI; 125c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng unsigned RefCount; 126c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntry(MachineInstr *cpemi, unsigned cpi, unsigned rc = 0) 127c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng : CPEMI(cpemi), CPI(cpi), RefCount(rc) {} 128c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng }; 129c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 130c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng /// CPEntries - Keep track of all of the constant pool entry machine 13188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// instructions. For each original constpool index (i.e. those that 13288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// existed upon entry to this pass), it keeps a vector of entries. 13388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// Original elements are cloned as we go along; the clones are 13488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen /// put in the vector of the original element, but have distinct CPIs. 135c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng std::vector<std::vector<CPEntry> > CPEntries; 1368494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 137af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// ImmBranch - One per immediate branch, keeping the machine instruction 138af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// pointer, conditional or unconditional, the max displacement, 139af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// and (if isCond is true) the corresponding unconditional branch 140af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// opcode. 141af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng struct ImmBranch { 142af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MachineInstr *MI; 143c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng unsigned MaxDisp : 31; 144c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng bool isCond : 1; 145af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng int UncondBr; 146c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng ImmBranch(MachineInstr *mi, unsigned maxdisp, bool cond, int ubr) 147c285414988ba026d01e5d8acc07a21cd06fd5732Evan Cheng : MI(mi), MaxDisp(maxdisp), isCond(cond), UncondBr(ubr) {} 148af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng }; 149af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 1502706f9771de8e90ee6379e70afedd91892bb9c8cEvan Cheng /// ImmBranches - Keep track of all the immediate branch instructions. 151af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng /// 152e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<ImmBranch> ImmBranches; 153af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 154d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// PushPopMIs - Keep track of all the Thumb push / pop instructions. 155d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// 156c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng SmallVector<MachineInstr*, 4> PushPopMIs; 157d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1585657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng /// T2JumpTables - Keep track of all the Thumb2 jumptable instructions. 1595657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng SmallVector<MachineInstr*, 4> T2JumpTables; 1605657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 161d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// HasFarJump - True if any far jump instruction has been emitted during 162d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng /// the branch fix up pass. 163d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng bool HasFarJump; 164d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1654d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach /// HasInlineAsm - True if the function contains inline assembly. 1664d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach bool HasInlineAsm; 1674d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach 1682062875a7d8f7dd94a20d9e3a298e9e216efb4b5Chris Lattner const ARMInstrInfo *TII; 16925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng const ARMSubtarget *STI; 1708593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen ARMFunctionInfo *AFI; 171b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen bool isThumb; 172d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool isThumb1; 1735e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin bool isThumb2; 174a8e2989ece6dc46df59b0768184028257f913843Evan Cheng public: 1751997473cf72957d0e70322e2fe6fe2ab141c58a6Devang Patel static char ID; 17690c579de5a383cee278acc3f7e7b9d0a656e6a35Owen Anderson ARMConstantIslands() : MachineFunctionPass(ID) {} 177794fd75c67a2cdc128d67342c6d88a504d186896Devang Patel 1785657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng virtual bool runOnMachineFunction(MachineFunction &MF); 179a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 180a8e2989ece6dc46df59b0768184028257f913843Evan Cheng virtual const char *getPassName() const { 181af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng return "ARM constant island placement and branch shortening pass"; 182a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 1838494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 184a8e2989ece6dc46df59b0768184028257f913843Evan Cheng private: 1855657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng void DoInitialPlacement(MachineFunction &MF, 186e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<MachineInstr*> &CPEMIs); 187c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntry *findConstPoolEntry(unsigned CPI, const MachineInstr *CPEMI); 18880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach void JumpTableFunctionScan(MachineFunction &MF); 1895657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng void InitialFunctionScan(MachineFunction &MF, 190e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng const std::vector<MachineInstr*> &CPEMIs); 1910c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng MachineBasicBlock *SplitBlockBeforeInstr(MachineInstr *MI); 192a8e2989ece6dc46df59b0768184028257f913843Evan Cheng void UpdateForInsertedWaterBlock(MachineBasicBlock *NewBB); 19399c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen void AdjustBBOffsetsAfter(MachineBasicBlock *BB, int delta); 194ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng bool DecrementOldEntry(unsigned CPI, MachineInstr* CPEMI); 19588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen int LookForExistingCPEntry(CPUser& U, unsigned UserOffset); 196b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson bool LookForWater(CPUser&U, unsigned UserOffset, water_iterator &WaterIter); 197b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen void CreateNewWater(unsigned CPUserIndex, unsigned UserOffset, 198757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson MachineBasicBlock *&NewMBB); 1995657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool HandleConstantPoolUser(MachineFunction &MF, unsigned CPUserIndex); 200ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng void RemoveDeadCPEMI(MachineInstr *CPEMI); 201ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng bool RemoveUnusedCPEntries(); 2028494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson bool CPEIsInRange(MachineInstr *MI, unsigned UserOffset, 2035d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng MachineInstr *CPEMI, unsigned Disp, bool NegOk, 2045d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool DoDump = false); 20599c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen bool WaterIsInRange(unsigned UserOffset, MachineBasicBlock *Water, 2065d9c4b60204d741c213456e21b87e9af6a3dc627Dale Johannesen CPUser &U); 20799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen bool OffsetIsInRange(unsigned UserOffset, unsigned TrialOffset, 208d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng unsigned Disp, bool NegativeOK, bool IsSoImm = false); 209c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng bool BBIsInRange(MachineInstr *MI, MachineBasicBlock *BB, unsigned Disp); 2105657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool FixUpImmediateBr(MachineFunction &MF, ImmBranch &Br); 2115657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool FixUpConditionalBr(MachineFunction &MF, ImmBranch &Br); 2125657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool FixUpUnconditionalBr(MachineFunction &MF, ImmBranch &Br); 213d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng bool UndoLRSpillRestore(); 214a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng bool OptimizeThumb2Instructions(MachineFunction &MF); 215a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng bool OptimizeThumb2Branches(MachineFunction &MF); 21680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach bool ReorderThumb2JumpTables(MachineFunction &MF); 2175657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool OptimizeThumb2JumpTables(MachineFunction &MF); 2181fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineBasicBlock *AdjustJTTargetBlockForward(MachineBasicBlock *BB, 2191fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineBasicBlock *JTBB); 220a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 221a8e2989ece6dc46df59b0768184028257f913843Evan Cheng unsigned GetOffsetOf(MachineInstr *MI) const; 2228593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen void dumpBBs(); 2235657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng void verify(MachineFunction &MF); 224a8e2989ece6dc46df59b0768184028257f913843Evan Cheng }; 2251997473cf72957d0e70322e2fe6fe2ab141c58a6Devang Patel char ARMConstantIslands::ID = 0; 226a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 227a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 2288593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// verify - check BBOffsets, BBSizes, alignment of islands 2295657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengvoid ARMConstantIslands::verify(MachineFunction &MF) { 2308593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen assert(BBOffsets.size() == BBSizes.size()); 2318593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen for (unsigned i = 1, e = BBOffsets.size(); i != e; ++i) 2328593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen assert(BBOffsets[i-1]+BBSizes[i-1] == BBOffsets[i]); 233d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (!isThumb) 234d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return; 235d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng#ifndef NDEBUG 2365657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 237d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MBBI != E; ++MBBI) { 238d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MachineBasicBlock *MBB = MBBI; 239d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (!MBB->empty() && 240d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MBB->begin()->getOpcode() == ARM::CONSTPOOL_ENTRY) { 241d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng unsigned MBBId = MBB->getNumber(); 2424d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach assert(HasInlineAsm || 2434d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach (BBOffsets[MBBId]%4 == 0 && BBSizes[MBBId]%4 == 0) || 244d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng (BBOffsets[MBBId]%4 != 0 && BBSizes[MBBId]%4 != 0)); 2458593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 2468593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 2474d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach for (unsigned i = 0, e = CPUsers.size(); i != e; ++i) { 2484d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach CPUser &U = CPUsers[i]; 2494d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach unsigned UserOffset = GetOffsetOf(U.MI) + (isThumb ? 4 : 8); 250a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach unsigned CPEOffset = GetOffsetOf(U.CPEMI); 251a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach unsigned Disp = UserOffset < CPEOffset ? CPEOffset - UserOffset : 252a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach UserOffset - CPEOffset; 253a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach assert(Disp <= U.MaxDisp || "Constant pool entry out of range!"); 2544d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach } 255a9562568e5c2a897e3a51b18700eeb70f0dda48cJim Grosbach#endif 2568593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen} 2578593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 2588593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// print block size and offset information - debugging 2598593e418555fdae21a070357fd8734b4069c17d0Dale Johannesenvoid ARMConstantIslands::dumpBBs() { 2608593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen for (unsigned J = 0, E = BBOffsets.size(); J !=E; ++J) { 261893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "block " << J << " offset " << BBOffsets[J] 262893e1c90a03a53cf13f73849324e83612688428aChris Lattner << " size " << BBSizes[J] << "\n"); 2638593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 2648593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen} 2658593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 266af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng/// createARMConstantIslandPass - returns an instance of the constpool 267af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng/// island pass. 268a8e2989ece6dc46df59b0768184028257f913843Evan ChengFunctionPass *llvm::createARMConstantIslandPass() { 269a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return new ARMConstantIslands(); 270a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 271a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 2725657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::runOnMachineFunction(MachineFunction &MF) { 2735657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineConstantPool &MCP = *MF.getConstantPool(); 2748494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 2752062875a7d8f7dd94a20d9e3a298e9e216efb4b5Chris Lattner TII = (const ARMInstrInfo*)MF.getTarget().getInstrInfo(); 2765657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng AFI = MF.getInfo<ARMFunctionInfo>(); 27725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng STI = &MF.getTarget().getSubtarget<ARMSubtarget>(); 27825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 279b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen isThumb = AFI->isThumbFunction(); 280d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng isThumb1 = AFI->isThumb1OnlyFunction(); 2815e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin isThumb2 = AFI->isThumb2Function(); 282d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 283d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng HasFarJump = false; 2844d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach HasInlineAsm = false; 285d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 286a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Renumber all of the machine basic blocks in the function, guaranteeing that 287a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // the numbers agree with the position of the block in the function. 2885657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.RenumberBlocks(); 289a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 29080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // Try to reorder and otherwise adjust the block layout to make good use 29180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // of the TB[BH] instructions. 29280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach bool MadeChange = false; 29380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach if (isThumb2 && AdjustJumpTableBlocks) { 29480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach JumpTableFunctionScan(MF); 29580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MadeChange |= ReorderThumb2JumpTables(MF); 29680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // Data is out of date, so clear it. It'll be re-computed later. 29780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach T2JumpTables.clear(); 29880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // Blocks may have shifted around. Keep the numbering up to date. 29980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MF.RenumberBlocks(); 30080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 30180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 302d26b14c34cbcee1448b86b524578fc51cc979023Evan Cheng // Thumb1 functions containing constant pools get 4-byte alignment. 303d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // This is so we can keep exact track of where the alignment padding goes. 304d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 3057d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner // ARM and Thumb2 functions need to be 4-byte aligned. 3067d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner if (!isThumb1) 3077d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner MF.EnsureAlignment(2); // 2 = log2(4) 30856c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen 309a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Perform the initial placement of the constant pool entries. To start with, 310a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // we put them all at the end of the function. 311e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng std::vector<MachineInstr*> CPEMIs; 31256c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen if (!MCP.isEmpty()) { 3135657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng DoInitialPlacement(MF, CPEMIs); 314d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (isThumb1) 3157d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner MF.EnsureAlignment(2); // 2 = log2(4) 31656c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen } 3178494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 318a8e2989ece6dc46df59b0768184028257f913843Evan Cheng /// The next UID to take is the first unused one. 3195de5d4b6d0eb3fd379fa571d82f6fa764460b3b8Evan Cheng AFI->initPICLabelUId(CPEMIs.size()); 3208494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 321a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Do the initial scan of the function, building up information about the 322a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // sizes of each block, the location of all the water, and finding all of the 323a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // constant pool users. 3245657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng InitialFunctionScan(MF, CPEMIs); 325a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CPEMIs.clear(); 3268086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen DEBUG(dumpBBs()); 3278086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 3288494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 329ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng /// Remove dead constant pool entries. 330cd080249fc249a51d8b0021a651d8b9d4a4977e0Bill Wendling MadeChange |= RemoveUnusedCPEntries(); 331ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 332d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // Iteratively place constant pool entries and fix up branches until there 333d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // is no change. 334b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng unsigned NoCPIters = 0, NoBRIters = 0; 335d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng while (true) { 336b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng bool CPChange = false; 337a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned i = 0, e = CPUsers.size(); i != e; ++i) 338b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng CPChange |= HandleConstantPoolUser(MF, i); 339b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng if (CPChange && ++NoCPIters > 30) 340b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng llvm_unreachable("Constant Island pass failed to converge!"); 3418202010364e1bfe6111f1ce62f154499b80877fbEvan Cheng DEBUG(dumpBBs()); 34226b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach 343b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Clear NewWaterList now. If we split a block for branches, it should 344b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // appear as "new water" for the next iteration of constant pool placement. 345b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.clear(); 346b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng 347b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng bool BRChange = false; 348af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng for (unsigned i = 0, e = ImmBranches.size(); i != e; ++i) 349b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng BRChange |= FixUpImmediateBr(MF, ImmBranches[i]); 350b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng if (BRChange && ++NoBRIters > 30) 351b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng llvm_unreachable("Branch Fix Up pass failed to converge!"); 3528202010364e1bfe6111f1ce62f154499b80877fbEvan Cheng DEBUG(dumpBBs()); 353b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng 354b6879b2b84df2f642cd39f5bf58584c4a39f8080Evan Cheng if (!CPChange && !BRChange) 355d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng break; 356d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MadeChange = true; 357d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng } 358ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 359a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // Shrink 32-bit Thumb2 branch, load, and store instructions. 360e44be6381609d31b2d8879dbd5107e01404fa475Evan Cheng if (isThumb2 && !STI->prefers32BitThumb()) 361a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MadeChange |= OptimizeThumb2Instructions(MF); 36225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 3638593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // After a while, this might be made debug-only, but it is not expensive. 3645657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng verify(MF); 3658593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 36626b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach // If LR has been forced spilled and no far jump (i.e. BL) has been issued, 36726b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach // undo the spill / restore of LR if possible. 3685657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (isThumb && !HasFarJump && AFI->isLRSpilledForFarJump()) 369d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MadeChange |= UndoLRSpillRestore(); 370d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 37198b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov // Save the mapping between original and cloned constpool entries. 37298b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov for (unsigned i = 0, e = CPEntries.size(); i != e; ++i) { 37398b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov for (unsigned j = 0, je = CPEntries[i].size(); j != je; ++j) { 37498b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov const CPEntry & CPE = CPEntries[i][j]; 37598b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov AFI->recordCPEClone(i, CPE.CPI); 37698b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov } 37798b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov } 37898b928ea71576c243bdb203879d966be9cde5f3cAnton Korobeynikov 379b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng DEBUG(errs() << '\n'; dumpBBs()); 380b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng 381a8e2989ece6dc46df59b0768184028257f913843Evan Cheng BBSizes.clear(); 38299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets.clear(); 383a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.clear(); 384a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CPUsers.clear(); 385c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntries.clear(); 386af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng ImmBranches.clear(); 387c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng PushPopMIs.clear(); 3885657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng T2JumpTables.clear(); 389d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 390d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return MadeChange; 391a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 392a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 393a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// DoInitialPlacement - Perform the initial placement of the constant pool 394a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// entries. To start with, we put them all at the end of the function. 3955657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengvoid ARMConstantIslands::DoInitialPlacement(MachineFunction &MF, 3968494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson std::vector<MachineInstr*> &CPEMIs) { 397a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Create the basic block to hold the CPE's. 3985657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *BB = MF.CreateMachineBasicBlock(); 3995657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.push_back(BB); 4008494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 401a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add all of the constants from the constant pool to the end block, use an 402a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // identity mapping of CPI's to CPE's. 403a8e2989ece6dc46df59b0768184028257f913843Evan Cheng const std::vector<MachineConstantPoolEntry> &CPs = 4045657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.getConstantPool()->getConstants(); 4058494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 4065657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const TargetData &TD = *MF.getTarget().getTargetData(); 407a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned i = 0, e = CPs.size(); i != e; ++i) { 408777d2306b36816a53bc1ae1244c0dc7d998ae691Duncan Sands unsigned Size = TD.getTypeAllocSize(CPs[i].getType()); 409a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Verify that all constant pool entries are a multiple of 4 bytes. If not, 410a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // we would have to pad them out or something so that instructions stay 411a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // aligned. 412a8e2989ece6dc46df59b0768184028257f913843Evan Cheng assert((Size & 3) == 0 && "CP Entry not multiple of 4 bytes!"); 413a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineInstr *CPEMI = 414c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(BB, DebugLoc(), TII->get(ARM::CONSTPOOL_ENTRY)) 415c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner .addImm(i).addConstantPoolIndex(i).addImm(Size); 416a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CPEMIs.push_back(CPEMI); 417c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 418c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Add a new CPEntry, but no corresponding CPUser yet. 419c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng std::vector<CPEntry> CPEs; 420c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEs.push_back(CPEntry(CPEMI, i)); 421c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntries.push_back(CPEs); 422fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCPEs; 423893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Moved CPI#" << i << " to end of function as #" << i 424893e1c90a03a53cf13f73849324e83612688428aChris Lattner << "\n"); 425a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 426a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 427a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 42888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// BBHasFallthrough - Return true if the specified basic block can fallthrough 429a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// into the block immediately after it. 430a8e2989ece6dc46df59b0768184028257f913843Evan Chengstatic bool BBHasFallthrough(MachineBasicBlock *MBB) { 431a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Get the next machine basic block in the function. 432a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineFunction::iterator MBBI = MBB; 43318f30e6f5e80787808fe1455742452a5210afe07Jim Grosbach // Can't fall off end of function. 43418f30e6f5e80787808fe1455742452a5210afe07Jim Grosbach if (llvm::next(MBBI) == MBB->getParent()->end()) 435a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return false; 4368494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 4377896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineBasicBlock *NextBB = llvm::next(MBBI); 438a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::succ_iterator I = MBB->succ_begin(), 439a8e2989ece6dc46df59b0768184028257f913843Evan Cheng E = MBB->succ_end(); I != E; ++I) 440a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (*I == NextBB) 441a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return true; 4428494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 443a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return false; 444a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 445a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 446c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// findConstPoolEntry - Given the constpool index and CONSTPOOL_ENTRY MI, 447c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// look up the corresponding CPEntry. 448c99ef085b90b32952b484e8843fb66ad65215b61Evan ChengARMConstantIslands::CPEntry 449c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng*ARMConstantIslands::findConstPoolEntry(unsigned CPI, 450c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng const MachineInstr *CPEMI) { 451c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng std::vector<CPEntry> &CPEs = CPEntries[CPI]; 452c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Number of entries per constpool index should be small, just do a 453c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // linear search. 454c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng for (unsigned i = 0, e = CPEs.size(); i != e; ++i) { 455c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng if (CPEs[i].CPEMI == CPEMI) 456c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return &CPEs[i]; 457c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng } 458c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return NULL; 459c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng} 460c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 46180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// JumpTableFunctionScan - Do a scan of the function, building up 46280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// information about the sizes of each block and the locations of all 46380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// the jump tables. 46480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbachvoid ARMConstantIslands::JumpTableFunctionScan(MachineFunction &MF) { 46580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 46680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MBBI != E; ++MBBI) { 46780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock &MBB = *MBBI; 46880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 46980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 47008cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach I != E; ++I) 47108cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach if (I->getDesc().isBranch() && I->getOpcode() == ARM::t2BR_JT) 47208cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach T2JumpTables.push_back(I); 47380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 47480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach} 47580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 476a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// InitialFunctionScan - Do the initial scan of the function, building up 477a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// information about the sizes of each block, the location of all the water, 478a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// and finding all of the constant pool users. 4795657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengvoid ARMConstantIslands::InitialFunctionScan(MachineFunction &MF, 480e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng const std::vector<MachineInstr*> &CPEMIs) { 4814d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // First thing, see if the function has any inline assembly in it. If so, 4824d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // we have to be conservative about alignment assumptions, as we don't 4834d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // know for sure the size of any instructions in the inline assembly. 4844d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 4854d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach MBBI != E; ++MBBI) { 4864d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach MachineBasicBlock &MBB = *MBBI; 4874d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 4884d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach I != E; ++I) 4894d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach if (I->getOpcode() == ARM::INLINEASM) 4904d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach HasInlineAsm = true; 4914d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach } 4924d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach 4939a4d2e40a02b6e5fab5ccf1c768a52c76f3aec6aBill Wendling // Now go back through the instructions and build up our data structures. 49499c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned Offset = 0; 4955657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 496a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MBBI != E; ++MBBI) { 497a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock &MBB = *MBBI; 4988494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 499a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // If this block doesn't fall through into the next MBB, then this is 500a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // 'water' that a constant pool island could be placed. 501a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (!BBHasFallthrough(&MBB)) 502a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.push_back(&MBB); 5038494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 504a8e2989ece6dc46df59b0768184028257f913843Evan Cheng unsigned MBBSize = 0; 505a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 506a8e2989ece6dc46df59b0768184028257f913843Evan Cheng I != E; ++I) { 5079cfcfeb24bf7182d40d8e8a54e350451b67a1136Jim Grosbach if (I->isDebugValue()) 5089cfcfeb24bf7182d40d8e8a54e350451b67a1136Jim Grosbach continue; 509a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add instruction size to MBBSize. 51052e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray MBBSize += TII->GetInstSizeInBytes(I); 511a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 512af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng int Opc = I->getOpcode(); 513749c6f6b5ed301c84aac562e414486549d7b98ebChris Lattner if (I->getDesc().isBranch()) { 514af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng bool isCond = false; 515af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng unsigned Bits = 0; 516af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng unsigned Scale = 1; 517af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng int UOpc = Opc; 518af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng switch (Opc) { 5195657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng default: 5205657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; // Ignore other JT branches 5218593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen case ARM::tBR_JTr: 52266ac53165e17b7c76b8c69e57bde623d44ec492eEvan Cheng // A Thumb1 table jump may involve padding; for the offsets to 5238593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // be right, functions containing these must be 4-byte aligned. 524b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng // tBR_JTr expands to a mov pc followed by .align 2 and then the jump 525b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng // table entries. So this code checks whether offset of tBR_JTr + 2 5268086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // is aligned. That is held in Offset+MBBSize, which already has 5278086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // 2 added in for the size of the mov pc instruction. 5287d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner MF.EnsureAlignment(2U); 5298086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen if ((Offset+MBBSize)%4 != 0 || HasInlineAsm) 5305657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng // FIXME: Add a pseudo ALIGN instruction instead. 5318593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen MBBSize += 2; // padding 5328593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen continue; // Does not get an entry in ImmBranches 5335657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng case ARM::t2BR_JT: 5345657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng T2JumpTables.push_back(I); 5355657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; // Does not get an entry in ImmBranches 536af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::Bcc: 537af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng isCond = true; 538af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng UOpc = ARM::B; 539af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // Fallthrough 540af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::B: 541af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 24; 542af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 4; 543af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 544af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::tBcc: 545af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng isCond = true; 546af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng UOpc = ARM::tB; 547af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 8; 548af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 2; 549af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 550af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::tB: 551af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 11; 552af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 2; 553af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 5545e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::t2Bcc: 5555e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin isCond = true; 5565e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin UOpc = ARM::t2B; 5575e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Bits = 20; 5585e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Scale = 2; 5595e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin break; 5605e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::t2B: 5615e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Bits = 24; 5625e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Scale = 2; 5635e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin break; 564af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng } 565b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng 566b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng // Record this immediate branch. 567bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng unsigned MaxOffs = ((1 << (Bits-1))-1) * Scale; 568b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng ImmBranches.push_back(ImmBranch(I, MaxOffs, isCond, UOpc)); 569af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng } 570af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 571d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng if (Opc == ARM::tPUSH || Opc == ARM::tPOP_RET) 572d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng PushPopMIs.push_back(I); 573d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 574d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (Opc == ARM::CONSTPOOL_ENTRY) 575d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng continue; 576d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 577a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Scan the instructions for constant pool operands. 578a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned op = 0, e = I->getNumOperands(); op != e; ++op) 579d735b8019b0f297d7c14b55adcd887af24d8e602Dan Gohman if (I->getOperand(op).isCPI()) { 580a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // We found one. The addressing mode tells us the max displacement 581a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // from the PC that this instruction permits. 5828494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 583a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Basic size info comes from the TSFlags field. 584b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng unsigned Bits = 0; 585b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng unsigned Scale = 1; 5865d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool NegOk = false; 587d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool IsSoImm = false; 588d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 589d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng switch (Opc) { 5908494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson default: 591c23197a26f34f559ea9797de51e187087c039c42Torok Edwin llvm_unreachable("Unknown addressing mode for CP reference!"); 592a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 593d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 594d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // Taking the address of a CP entry. 595d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::LEApcrel: 596d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // This takes a SoImm, which is 8 bit immediate rotated. We'll 597d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // pretend the maximum offset is 255 * 4. Since each instruction 598dec6de92d1425c88f319179fb4a0b0a23f781df9Jim Grosbach // 4 byte wide, this is always correct. We'll check for other 599d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // displacements that fits in a SoImm as well. 600d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 8; 601d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; 6025d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng NegOk = true; 603d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng IsSoImm = true; 604a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 6056b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson case ARM::t2LEApcrel: 606d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 12; 6075d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng NegOk = true; 608a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 609d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::tLEApcrel: 610b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Bits = 8; 611d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; 612a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 613d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 6143e5561247202bae994dd259a2d8dc4eff8f799f3Jim Grosbach case ARM::LDRi12: 615d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::LDRcp: 616971b83b67a9812556cdb97bb58aa96fb37af458dOwen Anderson case ARM::t2LDRpci: 617d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 12; // +-offset_12 618d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng NegOk = true; 619a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 620d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 621d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::tLDRpci: 622b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Bits = 8; 623b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Scale = 4; // +(offset_8*4) 624012f2d97b78e4eb9128f1d491f2c177768dbe527Evan Cheng break; 625d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 626e5165490b7ba24bb2f3043399e0d60e7f3bcf8a5Jim Grosbach case ARM::VLDRD: 627e5165490b7ba24bb2f3043399e0d60e7f3bcf8a5Jim Grosbach case ARM::VLDRS: 628d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 8; 629d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; // +-(offset_8*4) 630d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng NegOk = true; 631055b0310f862b91f33699037ce67d3ab8137c20cEvan Cheng break; 632a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 633b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng 634a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Remember that this is a user of a CP entry. 6358aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner unsigned CPI = I->getOperand(op).getIndex(); 636c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineInstr *CPEMI = CPEMIs[CPI]; 63731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned MaxOffs = ((1 << Bits)-1) * Scale; 638d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng CPUsers.push_back(CPUser(I, CPEMI, MaxOffs, NegOk, IsSoImm)); 639c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 640c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Increment corresponding CPEntry reference count. 641c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntry *CPE = findConstPoolEntry(CPI, CPEMI); 642c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng assert(CPE && "Cannot find a corresponding CPEntry!"); 643c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPE->RefCount++; 6448494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 645a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Instructions can only use one CP entry, don't bother scanning the 646a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // rest of the operands. 647a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 648a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 649a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 6502021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng 6518593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // In thumb mode, if this block is a constpool island, we may need padding 6528593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // so it's aligned on 4 byte boundary. 653b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (isThumb && 65405cc424082f797c5820b19f29f398c9cce9b9928Evan Cheng !MBB.empty() && 6558593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen MBB.begin()->getOpcode() == ARM::CONSTPOOL_ENTRY && 6564d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach ((Offset%4) != 0 || HasInlineAsm)) 6572021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng MBBSize += 2; 6582021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng 659a8e2989ece6dc46df59b0768184028257f913843Evan Cheng BBSizes.push_back(MBBSize); 66099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets.push_back(Offset); 66199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen Offset += MBBSize; 662a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 663a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 664a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 665a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// GetOffsetOf - Return the current offset of the specified machine instruction 666a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// from the start of the function. This offset changes as stuff is moved 667a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// around inside the function. 668a8e2989ece6dc46df59b0768184028257f913843Evan Chengunsigned ARMConstantIslands::GetOffsetOf(MachineInstr *MI) const { 669a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 6708494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 671a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // The offset is composed of two things: the sum of the sizes of all MBB's 672a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // before this instruction's block, and the offset from the start of the block 673a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // it is in. 67499c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned Offset = BBOffsets[MBB->getNumber()]; 675a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 6768593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // If we're looking for a CONSTPOOL_ENTRY in Thumb, see if this block has 6778593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // alignment padding, and compensate if so. 6788494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson if (isThumb && 6798494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MI->getOpcode() == ARM::CONSTPOOL_ENTRY && 6804d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach (Offset%4 != 0 || HasInlineAsm)) 6818593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen Offset += 2; 6828593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 683a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Sum instructions before MI in MBB. 684a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::iterator I = MBB->begin(); ; ++I) { 685a8e2989ece6dc46df59b0768184028257f913843Evan Cheng assert(I != MBB->end() && "Didn't find MI in its own basic block?"); 686a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (&*I == MI) return Offset; 68752e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray Offset += TII->GetInstSizeInBytes(I); 688a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 689a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 690a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 691a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// CompareMBBNumbers - Little predicate function to sort the WaterList by MBB 692a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// ID. 693a8e2989ece6dc46df59b0768184028257f913843Evan Chengstatic bool CompareMBBNumbers(const MachineBasicBlock *LHS, 694a8e2989ece6dc46df59b0768184028257f913843Evan Cheng const MachineBasicBlock *RHS) { 695a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return LHS->getNumber() < RHS->getNumber(); 696a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 697a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 698a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// UpdateForInsertedWaterBlock - When a block is newly inserted into the 699a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// machine function, it upsets all of the block numbers. Renumber the blocks 700a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// and update the arrays that parallel this numbering. 701a8e2989ece6dc46df59b0768184028257f913843Evan Chengvoid ARMConstantIslands::UpdateForInsertedWaterBlock(MachineBasicBlock *NewBB) { 702ab4c366274a582dd8146b2820c6b999cad5fce36Duncan Sands // Renumber the MBB's to keep them consecutive. 703a8e2989ece6dc46df59b0768184028257f913843Evan Cheng NewBB->getParent()->RenumberBlocks(NewBB); 7048494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 705a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Insert a size into BBSizes to align it properly with the (newly 706a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // renumbered) block numbers. 707a8e2989ece6dc46df59b0768184028257f913843Evan Cheng BBSizes.insert(BBSizes.begin()+NewBB->getNumber(), 0); 70899c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 70999c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // Likewise for BBOffsets. 71099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets.insert(BBOffsets.begin()+NewBB->getNumber(), 0); 7118494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 7128494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // Next, update WaterList. Specifically, we need to add NewMBB as having 713a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // available water after it. 714034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson water_iterator IP = 715a8e2989ece6dc46df59b0768184028257f913843Evan Cheng std::lower_bound(WaterList.begin(), WaterList.end(), NewBB, 716a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CompareMBBNumbers); 717a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.insert(IP, NewBB); 718a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 719a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 720a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 721a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// Split the basic block containing MI into two blocks, which are joined by 722b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson/// an unconditional branch. Update data structures and renumber blocks to 7230c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng/// account for this change and returns the newly created block. 7240c61584d05894a5543f690803191a8b0da05b8fcEvan ChengMachineBasicBlock *ARMConstantIslands::SplitBlockBeforeInstr(MachineInstr *MI) { 725a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock *OrigBB = MI->getParent(); 7268e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MachineFunction &MF = *OrigBB->getParent(); 727a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 728a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Create a new MBB for the code after the OrigBB. 7298494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MachineBasicBlock *NewBB = 7308494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MF.CreateMachineBasicBlock(OrigBB->getBasicBlock()); 731a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineFunction::iterator MBBI = OrigBB; ++MBBI; 7328e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MF.insert(MBBI, NewBB); 7338494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 734a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Splice the instructions starting with MI over to NewBB. 735a8e2989ece6dc46df59b0768184028257f913843Evan Cheng NewBB->splice(NewBB->end(), OrigBB, MI, OrigBB->end()); 7368494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 737a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add an unconditional branch from OrigBB to NewBB. 738a9b8b8d62c67e96bc4dc2ed25298c539102f8638Evan Cheng // Note the new unconditional branch is not being recorded. 739b67284057ee130114055309eabe0bcd1af13777dDale Johannesen // There doesn't seem to be meaningful DebugInfo available; this doesn't 740b67284057ee130114055309eabe0bcd1af13777dDale Johannesen // correspond to anything in the source. 74158541fd62707b6856beee3db9e254b0110607bb1Evan Cheng unsigned Opc = isThumb ? (isThumb2 ? ARM::t2B : ARM::tB) : ARM::B; 74251f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson if (!isThumb) 74351f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(OrigBB, DebugLoc(), TII->get(Opc)).addMBB(NewBB); 74451f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson else 74551f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(OrigBB, DebugLoc(), TII->get(Opc)).addMBB(NewBB) 74651f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson .addImm(ARMCC::AL).addReg(0); 747fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumSplit; 7488494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 749a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Update the CFG. All succs of OrigBB are now succs of NewBB. 750a8e2989ece6dc46df59b0768184028257f913843Evan Cheng while (!OrigBB->succ_empty()) { 751a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock *Succ = *OrigBB->succ_begin(); 752a8e2989ece6dc46df59b0768184028257f913843Evan Cheng OrigBB->removeSuccessor(Succ); 753a8e2989ece6dc46df59b0768184028257f913843Evan Cheng NewBB->addSuccessor(Succ); 7548494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 755a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // This pass should be run after register allocation, so there should be no 756a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // PHI nodes to update. 757518bb53485df640d7b7e3f6b0544099020c42aa7Chris Lattner assert((Succ->empty() || !Succ->begin()->isPHI()) 758a8e2989ece6dc46df59b0768184028257f913843Evan Cheng && "PHI nodes should be eliminated by now!"); 759a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 7608494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 761a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // OrigBB branches to NewBB. 762a8e2989ece6dc46df59b0768184028257f913843Evan Cheng OrigBB->addSuccessor(NewBB); 7638494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 764a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Update internal data structures to account for the newly inserted MBB. 76588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // This is almost the same as UpdateForInsertedWaterBlock, except that 76688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // the Water goes after OrigBB, not NewBB. 7678e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MF.RenumberBlocks(NewBB); 7688494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 76988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Insert a size into BBSizes to align it properly with the (newly 77088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // renumbered) block numbers. 77188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen BBSizes.insert(BBSizes.begin()+NewBB->getNumber(), 0); 7728494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 77399c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // Likewise for BBOffsets. 77499c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets.insert(BBOffsets.begin()+NewBB->getNumber(), 0); 77599c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 7768494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // Next, update WaterList. Specifically, we need to add OrigMBB as having 77788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // available water after it (but not if it's already there, which happens 77888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // when splitting before a conditional branch that is followed by an 77988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // unconditional branch - in that case we want to insert NewBB). 780034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson water_iterator IP = 78188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen std::lower_bound(WaterList.begin(), WaterList.end(), OrigBB, 78288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen CompareMBBNumbers); 78388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen MachineBasicBlock* WaterBB = *IP; 78488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (WaterBB == OrigBB) 7857896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner WaterList.insert(llvm::next(IP), NewBB); 78688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen else 78788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen WaterList.insert(IP, OrigBB); 788b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(OrigBB); 78988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 79099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned OrigBBI = OrigBB->getNumber(); 79199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned NewBBI = NewBB->getNumber(); 7928494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 79325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng int delta = isThumb1 ? 2 : 4; 7948086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 7958086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // Figure out how large the OrigBB is. As the first half of the original 7968086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // block, it cannot contain a tablejump. The size includes 7978086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // the new jump we added. (It should be possible to do this without 7988086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // recounting everything, but it's very confusing, and this is rarely 7998086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // executed.) 8008086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen unsigned OrigBBSize = 0; 8018086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen for (MachineBasicBlock::iterator I = OrigBB->begin(), E = OrigBB->end(); 8028086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen I != E; ++I) 8038086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen OrigBBSize += TII->GetInstSizeInBytes(I); 8048086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen BBSizes[OrigBBI] = OrigBBSize; 80599c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 80699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // ...and adjust BBOffsets for NewBB accordingly. 80799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets[NewBBI] = BBOffsets[OrigBBI] + BBSizes[OrigBBI]; 80899c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 8098086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // Figure out how large the NewMBB is. As the second half of the original 8108086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // block, it may contain a tablejump. 8118086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen unsigned NewBBSize = 0; 8128086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen for (MachineBasicBlock::iterator I = NewBB->begin(), E = NewBB->end(); 8138086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen I != E; ++I) 8148086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen NewBBSize += TII->GetInstSizeInBytes(I); 8158086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // Set the size of NewBB in BBSizes. It does not include any padding now. 8168086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen BBSizes[NewBBI] = NewBBSize; 8178086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 8188086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen MachineInstr* ThumbJTMI = prior(NewBB->end()); 8198086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen if (ThumbJTMI->getOpcode() == ARM::tBR_JTr) { 8208086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // We've added another 2-byte instruction before this tablejump, which 8218086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // means we will always need padding if we didn't before, and vice versa. 8228086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 8238086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // The original offset of the jump instruction was: 8248086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen unsigned OrigOffset = BBOffsets[OrigBBI] + BBSizes[OrigBBI] - delta; 8258086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen if (OrigOffset%4 == 0) { 8268086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // We had padding before and now we don't. No net change in code size. 8278086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen delta = 0; 8288086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen } else { 8298086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // We didn't have padding before and now we do. 8308086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen BBSizes[NewBBI] += 2; 8318086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen delta = 4; 8328086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen } 8338086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen } 8348086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 83599c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // All BBOffsets following these blocks must be modified. 8368086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen if (delta) 8378086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen AdjustBBOffsetsAfter(NewBB, delta); 8380c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng 8390c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng return NewBB; 840a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 841a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 8428593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// OffsetIsInRange - Checks whether UserOffset (the location of a constant pool 8438494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson/// reference) is within MaxDisp of TrialOffset (a proposed location of a 8448593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// constant pool entry). 8458494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilsonbool ARMConstantIslands::OffsetIsInRange(unsigned UserOffset, 846d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng unsigned TrialOffset, unsigned MaxDisp, 847d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool NegativeOK, bool IsSoImm) { 8488494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // On Thumb offsets==2 mod 4 are rounded down by the hardware for 8498494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // purposes of the displacement computation; compensate for that here. 8508593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Effectively, the valid range of displacements is 2 bytes smaller for such 8518593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // references. 85231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned TotalAdj = 0; 85331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb && UserOffset%4 !=0) { 8548593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen UserOffset -= 2; 85531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng TotalAdj = 2; 85631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 8578593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // CPEs will be rounded up to a multiple of 4. 85831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb && TrialOffset%4 != 0) { 8598593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen TrialOffset += 2; 86031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng TotalAdj += 2; 86131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 86231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 86331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // In Thumb2 mode, later branch adjustments can shift instructions up and 86431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // cause alignment change. In the worst case scenario this can cause the 86531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // user's effective address to be subtracted by 2 and the CPE's address to 86631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // be plus 2. 86731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb2 && TotalAdj != 4) 86831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng MaxDisp -= (4 - TotalAdj); 8698593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 87099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen if (UserOffset <= TrialOffset) { 87199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // User before the Trial. 872d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (TrialOffset - UserOffset <= MaxDisp) 873d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return true; 87440efc251cd7a52dd2375ec95ee38b1be4572178fEvan Cheng // FIXME: Make use full range of soimm values. 87599c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen } else if (NegativeOK) { 876d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (UserOffset - TrialOffset <= MaxDisp) 877d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return true; 87840efc251cd7a52dd2375ec95ee38b1be4572178fEvan Cheng // FIXME: Make use full range of soimm values. 87999c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen } 88099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen return false; 88199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen} 88299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 88388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// WaterIsInRange - Returns true if a CPE placed after the specified 88488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// Water (a basic block) will be in range for the specific MI. 88588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 88688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesenbool ARMConstantIslands::WaterIsInRange(unsigned UserOffset, 8875d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng MachineBasicBlock* Water, CPUser &U) { 8885d9c4b60204d741c213456e21b87e9af6a3dc627Dale Johannesen unsigned MaxDisp = U.MaxDisp; 8898494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson unsigned CPEOffset = BBOffsets[Water->getNumber()] + 89088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen BBSizes[Water->getNumber()]; 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) { 94199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets[i] += 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) { 9504a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng unsigned OldOffset = BBOffsets[i] - delta; 9514a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng if ((OldOffset%4) == 0 && (BBOffsets[i]%4) != 0) { 952d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // add new padding 953d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng BBSizes[i] += 2; 954d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta += 2; 9554a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng } else if ((OldOffset%4) != 0 && (BBOffsets[i]%4) == 0) { 956d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // remove existing padding 9574a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng BBSizes[i] -= 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 973d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng BBSizes[i] -= 2; 974d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta -= 2; 9754a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng } else if ((OldMIOffset%4) != 0 && (NewMIOffset%4) == 0) { 976d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // add new padding 977d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng BBSizes[i] += 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(); 10993b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson if (isThumb && 11003b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson (BBOffsets[WBBId] + BBSizes[WBBId])%4 != 0) { 11013b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson // This is valid Water, but would introduce padding. Remember 11023b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson // it in case we don't find any Water that doesn't do this. 110332c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson if (!FoundWaterThatWouldPad) { 110432c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson FoundWaterThatWouldPad = true; 11053b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson IPThatWouldPad = IP; 1106f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 11073b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson } else { 1108b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterIter = IP; 11093b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson return true; 1110d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng } 111188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 11123b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson if (IP == B) 11133b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson break; 111488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 111532c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson if (FoundWaterThatWouldPad) { 1116b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterIter = IPThatWouldPad; 11178593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 11188593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 1119b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen return false; 1120b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen} 112188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 11228494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson/// CreateNewWater - No existing WaterList entry will work for 1123b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// CPUsers[CPUserIndex], so create a place to put the CPE. The end of the 1124b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// block is used if in range, and the conditional branch munged so control 1125b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// flow is correct. Otherwise the block is split to create a hole with an 1126757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson/// unconditional branch around it. In either case NewMBB is set to a 1127b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// block following which the new island can be inserted (the WaterList 1128b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// is not adjusted). 11298494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilsonvoid ARMConstantIslands::CreateNewWater(unsigned CPUserIndex, 1130757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson unsigned UserOffset, 1131757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson MachineBasicBlock *&NewMBB) { 1132b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUser &U = CPUsers[CPUserIndex]; 1133b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *UserMI = U.MI; 1134b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *CPEMI = U.CPEMI; 1135b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineBasicBlock *UserMBB = UserMI->getParent(); 11368494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson unsigned OffsetOfNextBlock = BBOffsets[UserMBB->getNumber()] + 1137b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen BBSizes[UserMBB->getNumber()]; 11388593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen assert(OffsetOfNextBlock== BBOffsets[UserMBB->getNumber()+1]); 1139b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 114036fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // If the block does not end in an unconditional branch already, and if the 114136fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // end of the block is within range, make new water there. (The addition 114236fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // below is for the unconditional branch we will be adding: 4 bytes on ARM + 114336fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // Thumb2, 2 on Thumb1. Possible Thumb1 alignment padding is allowed for 11448593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // inside OffsetIsInRange. 114536fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson if (BBHasFallthrough(UserMBB) && 1146d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng OffsetIsInRange(UserOffset, OffsetOfNextBlock + (isThumb1 ? 2: 4), 1147d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng U.MaxDisp, U.NegOk, U.IsSoImm)) { 1148893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Split at end of block\n"); 1149b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (&UserMBB->back() == UserMI) 1150b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen assert(BBHasFallthrough(UserMBB) && "Expected a fallthrough BB!"); 11517896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner NewMBB = llvm::next(MachineFunction::iterator(UserMBB)); 1152b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // Add an unconditional branch from UserMBB to fallthrough block. 1153b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // Record it for branch lengthening; this new branch will not get out of 1154b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // range, but if the preceding conditional branch is out of range, the 1155b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // targets will be exchanged, and the altered branch may be out of 1156b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // range, so the machinery has to know about it. 11575e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin int UncondBr = isThumb ? ((isThumb2) ? ARM::t2B : ARM::tB) : ARM::B; 115851f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson if (!isThumb) 115951f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(UserMBB, DebugLoc(), TII->get(UncondBr)).addMBB(NewMBB); 116051f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson else 116151f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(UserMBB, DebugLoc(), TII->get(UncondBr)).addMBB(NewMBB) 116251f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson .addImm(ARMCC::AL).addReg(0); 1163b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned MaxDisp = getUnconditionalBrDisp(UncondBr); 11648494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson ImmBranches.push_back(ImmBranch(&UserMBB->back(), 1165b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MaxDisp, false, UncondBr)); 1166d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng int delta = isThumb1 ? 2 : 4; 1167b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen BBSizes[UserMBB->getNumber()] += delta; 1168b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen AdjustBBOffsetsAfter(UserMBB, delta); 1169b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen } else { 1170b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // What a big block. Find a place within the block to split it. 1171d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // This is a little tricky on Thumb1 since instructions are 2 bytes 1172b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // and constant pool entries are 4 bytes: if instruction I references 1173b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // island CPE, and instruction I+1 references CPE', it will 1174b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // not work well to put CPE as far forward as possible, since then 1175b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // CPE' cannot immediately follow it (that location is 2 bytes 1176b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // farther away from I+1 than CPE was from I) and we'd need to create 11778593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // a new island. So, we make a first guess, then walk through the 11788593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // instructions between the one currently being looked at and the 11798593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // possible insertion point, and make sure any other instructions 11808593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // that reference CPEs will be able to use the same island area; 11818593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // if not, we back up the insertion point. 11828593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 1183b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // The 4 in the following is for the unconditional branch we'll be 1184d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // inserting (allows for long branch on Thumb1). Alignment of the 11858593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // island is handled inside OffsetIsInRange. 11868593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen unsigned BaseInsertOffset = UserOffset + U.MaxDisp -4; 1187b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // This could point off the end of the block if we've already got 1188b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // constant pool entries following this block; only the last one is 1189b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // in the water list. Back past any possible branches (allow for a 1190b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // conditional and a maximally long unconditional). 1191b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (BaseInsertOffset >= BBOffsets[UserMBB->getNumber()+1]) 11928494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson BaseInsertOffset = BBOffsets[UserMBB->getNumber()+1] - 1193d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng (isThumb1 ? 6 : 8); 1194b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned EndInsertOffset = BaseInsertOffset + 1195b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPEMI->getOperand(2).getImm(); 1196b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineBasicBlock::iterator MI = UserMI; 1197b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen ++MI; 1198b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned CPUIndex = CPUserIndex+1; 1199719510a178a910feb1db707140011c32a30992c4Evan Cheng unsigned NumCPUsers = CPUsers.size(); 1200719510a178a910feb1db707140011c32a30992c4Evan Cheng MachineInstr *LastIT = 0; 120152e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray for (unsigned Offset = UserOffset+TII->GetInstSizeInBytes(UserMI); 1202b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen Offset < BaseInsertOffset; 120352e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray Offset += TII->GetInstSizeInBytes(MI), 1204719510a178a910feb1db707140011c32a30992c4Evan Cheng MI = llvm::next(MI)) { 1205719510a178a910feb1db707140011c32a30992c4Evan Cheng if (CPUIndex < NumCPUsers && CPUsers[CPUIndex].MI == MI) { 1206d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng CPUser &U = CPUsers[CPUIndex]; 12078494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson if (!OffsetIsInRange(Offset, EndInsertOffset, 1208d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng U.MaxDisp, U.NegOk, U.IsSoImm)) { 1209d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng BaseInsertOffset -= (isThumb1 ? 2 : 4); 1210d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng EndInsertOffset -= (isThumb1 ? 2 : 4); 1211f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 1212b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // This is overly conservative, as we don't account for CPEMIs 1213b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // being reused within the block, but it doesn't matter much. 1214b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen EndInsertOffset += CPUsers[CPUIndex].CPEMI->getOperand(2).getImm(); 1215b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUIndex++; 1216f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 1217719510a178a910feb1db707140011c32a30992c4Evan Cheng 1218719510a178a910feb1db707140011c32a30992c4Evan Cheng // Remember the last IT instruction. 1219719510a178a910feb1db707140011c32a30992c4Evan Cheng if (MI->getOpcode() == ARM::t2IT) 1220719510a178a910feb1db707140011c32a30992c4Evan Cheng LastIT = MI; 122188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 1222719510a178a910feb1db707140011c32a30992c4Evan Cheng 1223893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Split in middle of big block\n"); 1224719510a178a910feb1db707140011c32a30992c4Evan Cheng --MI; 1225719510a178a910feb1db707140011c32a30992c4Evan Cheng 1226719510a178a910feb1db707140011c32a30992c4Evan Cheng // Avoid splitting an IT block. 1227719510a178a910feb1db707140011c32a30992c4Evan Cheng if (LastIT) { 1228719510a178a910feb1db707140011c32a30992c4Evan Cheng unsigned PredReg = 0; 1229719510a178a910feb1db707140011c32a30992c4Evan Cheng ARMCC::CondCodes CC = llvm::getITInstrPredicate(MI, PredReg); 1230719510a178a910feb1db707140011c32a30992c4Evan Cheng if (CC != ARMCC::AL) 1231719510a178a910feb1db707140011c32a30992c4Evan Cheng MI = LastIT; 1232719510a178a910feb1db707140011c32a30992c4Evan Cheng } 1233719510a178a910feb1db707140011c32a30992c4Evan Cheng NewMBB = SplitBlockBeforeInstr(MI); 1234b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen } 1235b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen} 1236b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1237b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// HandleConstantPoolUser - Analyze the specified user, checking to see if it 123839bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson/// is out-of-range. If so, pick up the constant pool value and move it some 1239b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// place in-range. Return true if we changed any addresses (thus must run 1240b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// another pass of branch lengthening), false otherwise. 12415657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::HandleConstantPoolUser(MachineFunction &MF, 12428494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson unsigned CPUserIndex) { 1243b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUser &U = CPUsers[CPUserIndex]; 1244b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *UserMI = U.MI; 1245b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *CPEMI = U.CPEMI; 12468aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner unsigned CPI = CPEMI->getOperand(1).getIndex(); 1247b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned Size = CPEMI->getOperand(2).getImm(); 12488593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Compute this only once, it's expensive. The 4 or 8 is the value the 1249a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // hardware keeps in the PC. 1250b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned UserOffset = GetOffsetOf(UserMI) + (isThumb ? 4 : 8); 1251768c9f725bda048b3406b6289beb586ff6e933dfEvan Cheng 1252b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // See if the current entry is within range, or there is a clone of it 1253b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // in range. 1254b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen int result = LookForExistingCPEntry(U, UserOffset); 1255b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (result==1) return false; 1256b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen else if (result==2) return true; 1257b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1258b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // No existing clone of this CPE is within range. 1259b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // We will be generating a new clone. Get a UID for it. 12605de5d4b6d0eb3fd379fa571d82f6fa764460b3b8Evan Cheng unsigned ID = AFI->createPICLabelUId(); 1261b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1262f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson // Look for water where we can place this CPE. 1263b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *NewIsland = MF.CreateMachineBasicBlock(); 1264b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *NewMBB; 1265b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson water_iterator IP; 1266b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (LookForWater(U, UserOffset, IP)) { 1267b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson DEBUG(errs() << "found water in range\n"); 1268b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *WaterBB = *IP; 1269b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1270b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // If the original WaterList entry was "new water" on this iteration, 1271b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // propagate that to the new island. This is just keeping NewWaterList 1272b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // updated to match the WaterList, which will be updated below. 1273b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (NewWaterList.count(WaterBB)) { 1274b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.erase(WaterBB); 1275b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(NewIsland); 1276b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson } 1277b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // The new CPE goes before the following block (NewMBB). 12787896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner NewMBB = llvm::next(MachineFunction::iterator(WaterBB)); 1279b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1280b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson } else { 1281b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // No water found. 1282893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "No water found\n"); 1283757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson CreateNewWater(CPUserIndex, UserOffset, NewMBB); 1284b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1285b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // SplitBlockBeforeInstr adds to WaterList, which is important when it is 1286b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // called while handling branches so that the water will be seen on the 1287b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // next iteration for constant pools, but in this context, we don't want 1288b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // it. Check for this so it will be removed from the WaterList. 1289b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Also remove any entry from NewWaterList. 1290b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *WaterBB = prior(MachineFunction::iterator(NewMBB)); 1291b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson IP = std::find(WaterList.begin(), WaterList.end(), WaterBB); 1292b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (IP != WaterList.end()) 1293b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.erase(WaterBB); 1294b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1295b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // We are adding new water. Update NewWaterList. 1296b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(NewIsland); 129788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 129888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 1299b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Remove the original WaterList entry; we want subsequent insertions in 1300b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // this vicinity to go after the one we're about to insert. This 1301b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // considerably reduces the number of times we have to move the same CPE 1302b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // more than once and is also important to ensure the algorithm terminates. 1303b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (IP != WaterList.end()) 1304b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterList.erase(IP); 1305b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 130688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Okay, we know we can put an island before NewMBB now, do it! 13075657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.insert(NewMBB, NewIsland); 130888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 130988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Update internal data structures to account for the newly inserted MBB. 131088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen UpdateForInsertedWaterBlock(NewIsland); 131188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 131288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Decrement the old entry, and remove it if refcount becomes 0. 1313ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng DecrementOldEntry(CPI, CPEMI); 131488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 131588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Now that we have an island to add the CPE to, clone the original CPE and 131688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // add it to the island. 1317549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson U.HighWaterMark = NewIsland; 1318c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner U.CPEMI = BuildMI(NewIsland, DebugLoc(), TII->get(ARM::CONSTPOOL_ENTRY)) 1319a8e2989ece6dc46df59b0768184028257f913843Evan Cheng .addImm(ID).addConstantPoolIndex(CPI).addImm(Size); 132088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen CPEntries[CPI].push_back(CPEntry(U.CPEMI, ID, 1)); 1321fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCPEs; 1322c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 13238593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen BBOffsets[NewIsland->getNumber()] = BBOffsets[NewMBB->getNumber()]; 1324b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng // Compensate for .align 2 in thumb mode. 13254d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach if (isThumb && (BBOffsets[NewIsland->getNumber()]%4 != 0 || HasInlineAsm)) 13268593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen Size += 2; 1327a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Increase the size of the island block to account for the new entry. 1328a8e2989ece6dc46df59b0768184028257f913843Evan Cheng BBSizes[NewIsland->getNumber()] += Size; 132999c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen AdjustBBOffsetsAfter(NewIsland, Size); 13308494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1331a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Finally, change the CPI in the instruction operand to be ID. 1332a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned i = 0, e = UserMI->getNumOperands(); i != e; ++i) 1333d735b8019b0f297d7c14b55adcd887af24d8e602Dan Gohman if (UserMI->getOperand(i).isCPI()) { 13348aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner UserMI->getOperand(i).setIndex(ID); 1335a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 1336a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 13378494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1338705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Moved CPE to #" << ID << " CPI=" << CPI 1339705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << '\t' << *UserMI); 13408494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1341a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return true; 1342a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 1343a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 1344ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// RemoveDeadCPEMI - Remove a dead constant pool entry instruction. Update 1345ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// sizes and offsets of impacted basic blocks. 1346ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Chengvoid ARMConstantIslands::RemoveDeadCPEMI(MachineInstr *CPEMI) { 1347ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng MachineBasicBlock *CPEBB = CPEMI->getParent(); 13488593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen unsigned Size = CPEMI->getOperand(2).getImm(); 13498593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen CPEMI->eraseFromParent(); 13508593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen BBSizes[CPEBB->getNumber()] -= Size; 13518593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // All succeeding offsets have the current size value added in, fix this. 1352ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (CPEBB->empty()) { 1353d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // In thumb1 mode, the size of island may be padded by two to compensate for 13548593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // the alignment requirement. Then it will now be 2 when the block is 1355ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng // empty, so fix this. 1356ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng // All succeeding offsets have the current size value added in, fix this. 1357ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (BBSizes[CPEBB->getNumber()] != 0) { 13588593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen Size += BBSizes[CPEBB->getNumber()]; 1359ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng BBSizes[CPEBB->getNumber()] = 0; 1360ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 1361ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 13628593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen AdjustBBOffsetsAfter(CPEBB, -Size); 13638593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // An island has only one predecessor BB and one successor BB. Check if 13648593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // this BB's predecessor jumps directly to this BB's successor. This 13658593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // shouldn't happen currently. 13668593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen assert(!BBIsJumpedOver(CPEBB) && "How did this happen?"); 13678593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // FIXME: remove the empty blocks after all the work is done? 1368ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng} 1369ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 1370ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// RemoveUnusedCPEntries - Remove constant pool entries whose refcounts 1371ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// are zero. 1372ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Chengbool ARMConstantIslands::RemoveUnusedCPEntries() { 1373ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng unsigned MadeChange = false; 1374ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng for (unsigned i = 0, e = CPEntries.size(); i != e; ++i) { 1375ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng std::vector<CPEntry> &CPEs = CPEntries[i]; 1376ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng for (unsigned j = 0, ee = CPEs.size(); j != ee; ++j) { 1377ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (CPEs[j].RefCount == 0 && CPEs[j].CPEMI) { 1378ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng RemoveDeadCPEMI(CPEs[j].CPEMI); 1379ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng CPEs[j].CPEMI = NULL; 1380ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng MadeChange = true; 1381ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 1382ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 13838494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson } 1384ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng return MadeChange; 1385ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng} 1386ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 138788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// BBIsInRange - Returns true if the distance between specific MI and 138843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng/// specific BB can fit in MI's displacement field. 1389c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Chengbool ARMConstantIslands::BBIsInRange(MachineInstr *MI,MachineBasicBlock *DestBB, 1390c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng unsigned MaxDisp) { 1391b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned PCAdj = isThumb ? 4 : 8; 1392c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng unsigned BrOffset = GetOffsetOf(MI) + PCAdj; 139399c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned DestOffset = BBOffsets[DestBB->getNumber()]; 139443aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1395705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << "Branch of destination BB#" << DestBB->getNumber() 1396705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " from BB#" << MI->getParent()->getNumber() 1397705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " max delta=" << MaxDisp 1398705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " from " << GetOffsetOf(MI) << " to " << DestOffset 1399705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " offset " << int(DestOffset-BrOffset) << "\t" << *MI); 1400c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng 14018593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (BrOffset <= DestOffset) { 14028593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Branch before the Dest. 14038593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (DestOffset-BrOffset <= MaxDisp) 14048593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 14058593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } else { 14068593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (BrOffset-DestOffset <= MaxDisp) 14078593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 14088593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 14098593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return false; 141043aeab68a69e443c528092b4424a498d813f96b7Evan Cheng} 141143aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1412d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// FixUpImmediateBr - Fix up an immediate branch whose destination is too far 1413d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// away to fit in its displacement field. 14145657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::FixUpImmediateBr(MachineFunction &MF, ImmBranch &Br) { 1415d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = Br.MI; 14168aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *DestBB = MI->getOperand(0).getMBB(); 1417d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1418c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng // Check to see if the DestBB is already in-range. 1419c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng if (BBIsInRange(MI, DestBB, Br.MaxDisp)) 1420d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return false; 1421d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1422d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng if (!Br.isCond) 14235657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return FixUpUnconditionalBr(MF, Br); 14245657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return FixUpConditionalBr(MF, Br); 1425d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 1426d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 142788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// FixUpUnconditionalBr - Fix up an unconditional branch whose destination is 142888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// too far away to fit in its displacement field. If the LR register has been 1429d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// spilled in the epilogue, then we can use BL to implement a far jump. 143039bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson/// Otherwise, add an intermediate branch instruction to a branch. 1431d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Chengbool 14325657c01949dca6c012ac60d242d1a8d2ffdf5603Evan ChengARMConstantIslands::FixUpUnconditionalBr(MachineFunction &MF, ImmBranch &Br) { 1433d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = Br.MI; 1434d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineBasicBlock *MBB = MI->getParent(); 143553c67c0218d8420234dd71bf2d9df3388909af77Evan Cheng if (!isThumb1) 143653c67c0218d8420234dd71bf2d9df3388909af77Evan Cheng llvm_unreachable("FixUpUnconditionalBr is Thumb1 only!"); 1437d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1438d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // Use BL to implement far jump. 1439d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng Br.MaxDisp = (1 << 21) * 2; 14405080f4d9919d39b367891dc51e739c571a66036cChris Lattner MI->setDesc(TII->get(ARM::tBfar)); 14410af0dc8ac6d084bb04cf0188e48eecd6c98903baOwen Anderson MI->addOperand(MachineOperand::CreateImm((int64_t)ARMCC::AL)); 14420af0dc8ac6d084bb04cf0188e48eecd6c98903baOwen Anderson MI->addOperand(MachineOperand::CreateReg(0, false)); 1443d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng BBSizes[MBB->getNumber()] += 2; 144499c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen AdjustBBOffsetsAfter(MBB, 2); 1445d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng HasFarJump = true; 1446fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumUBrFixed; 1447bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng 1448705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Changed B to long jump " << *MI); 1449bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng 1450d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return true; 1451d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 1452d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 145388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// FixUpConditionalBr - Fix up a conditional branch whose destination is too 1454d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// far away to fit in its displacement field. It is converted to an inverse 1455d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// conditional branch + an unconditional branch to the destination. 1456af5cbcb809bdbd30ebacab942994721c134d16a2Evan Chengbool 14575657c01949dca6c012ac60d242d1a8d2ffdf5603Evan ChengARMConstantIslands::FixUpConditionalBr(MachineFunction &MF, ImmBranch &Br) { 1458af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MachineInstr *MI = Br.MI; 14598aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *DestBB = MI->getOperand(0).getMBB(); 1460af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 146139bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // Add an unconditional branch to the destination and invert the branch 1462d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // condition to jump over it: 1463af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // blt L1 1464af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // => 1465af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // bge L2 1466af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // b L1 1467af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // L2: 14689a1ceaedc282f0cae31f2723f4d6c00c7b88fe90Chris Lattner ARMCC::CondCodes CC = (ARMCC::CondCodes)MI->getOperand(1).getImm(); 1469af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng CC = ARMCC::getOppositeCondition(CC); 14700e1d37904abbf7e8c4c478408253dd995f3040f4Evan Cheng unsigned CCReg = MI->getOperand(2).getReg(); 1471af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 1472af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // If the branch is at the end of its MBB and that has a fall-through block, 1473af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // direct the updated conditional branch to the fall-through block. Otherwise, 1474af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // split the MBB before the next instruction. 1475af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 1476bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng MachineInstr *BMI = &MBB->back(); 1477bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng bool NeedSplit = (BMI != MI) || !BBHasFallthrough(MBB); 147843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1479fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCBrFixed; 1480bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng if (BMI != MI) { 14817896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner if (llvm::next(MachineBasicBlock::iterator(MI)) == prior(MBB->end()) && 1482bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng BMI->getOpcode() == Br.UncondBr) { 148339bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // Last MI in the BB is an unconditional branch. Can we simply invert the 148443aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // condition and swap destinations: 148543aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // beq L1 148643aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // b L2 148743aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // => 148843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // bne L2 148943aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // b L1 14908aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *NewDest = BMI->getOperand(0).getMBB(); 1491c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng if (BBIsInRange(MI, NewDest, Br.MaxDisp)) { 1492705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Invert Bcc condition and swap its destination with " 1493705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << *BMI); 14948aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner BMI->getOperand(0).setMBB(DestBB); 14958aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MI->getOperand(0).setMBB(NewDest); 149643aeab68a69e443c528092b4424a498d813f96b7Evan Cheng MI->getOperand(1).setImm(CC); 149743aeab68a69e443c528092b4424a498d813f96b7Evan Cheng return true; 149843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 149943aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 150043aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 150143aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 150243aeab68a69e443c528092b4424a498d813f96b7Evan Cheng if (NeedSplit) { 1503af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng SplitBlockBeforeInstr(MI); 150439bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // No need for the branch to the next block. We're adding an unconditional 1505dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng // branch to the destination. 150652e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray int delta = TII->GetInstSizeInBytes(&MBB->back()); 150756c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen BBSizes[MBB->getNumber()] -= delta; 15087896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineBasicBlock* SplitBB = llvm::next(MachineFunction::iterator(MBB)); 15098593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen AdjustBBOffsetsAfter(SplitBB, -delta); 1510dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng MBB->back().eraseFromParent(); 15118593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // BBOffsets[SplitBB] is wrong temporarily, fixed below 1512dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng } 15137896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineBasicBlock *NextBB = llvm::next(MachineFunction::iterator(MBB)); 15148494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1515893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << " Insert B to BB#" << DestBB->getNumber() 1516893e1c90a03a53cf13f73849324e83612688428aChris Lattner << " also invert condition and change dest. to BB#" 1517893e1c90a03a53cf13f73849324e83612688428aChris Lattner << NextBB->getNumber() << "\n"); 1518af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 151956c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen // Insert a new conditional branch and a new unconditional branch. 1520af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // Also update the ImmBranch as well as adding a new entry for the new branch. 1521c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(MBB, DebugLoc(), TII->get(MI->getOpcode())) 1522b67284057ee130114055309eabe0bcd1af13777dDale Johannesen .addMBB(NextBB).addImm(CC).addReg(CCReg); 1523af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Br.MI = &MBB->back(); 152452e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray BBSizes[MBB->getNumber()] += TII->GetInstSizeInBytes(&MBB->back()); 1525cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson if (isThumb) 1526cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson BuildMI(MBB, DebugLoc(), TII->get(Br.UncondBr)).addMBB(DestBB) 1527cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson .addImm(ARMCC::AL).addReg(0); 1528cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson else 1529cd4338fff5cc9427003766519bebcfa213b32d61Owen Anderson BuildMI(MBB, DebugLoc(), TII->get(Br.UncondBr)).addMBB(DestBB); 153052e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray BBSizes[MBB->getNumber()] += TII->GetInstSizeInBytes(&MBB->back()); 1531a9b8b8d62c67e96bc4dc2ed25298c539102f8638Evan Cheng unsigned MaxDisp = getUnconditionalBrDisp(Br.UncondBr); 1532a0bf794eb60b6795a121efcb9ff759e9e0955772Evan Cheng ImmBranches.push_back(ImmBranch(&MBB->back(), MaxDisp, false, Br.UncondBr)); 153356c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen 153456c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen // Remove the old conditional branch. It may or may not still be in MBB. 153552e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray BBSizes[MI->getParent()->getNumber()] -= TII->GetInstSizeInBytes(MI); 1536af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MI->eraseFromParent(); 1537af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 153856c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen // The net size change is an addition of one unconditional branch. 153952e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray int delta = TII->GetInstSizeInBytes(&MBB->back()); 154099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen AdjustBBOffsetsAfter(MBB, delta); 1541af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng return true; 1542af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng} 1543d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1544d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// UndoLRSpillRestore - Remove Thumb push / pop instructions that only spills 15454b322e58b77d16f103d88a3af3a4ebd2675245a0Evan Cheng/// LR / restores LR to pc. FIXME: This is done here because it's only possible 15464b322e58b77d16f103d88a3af3a4ebd2675245a0Evan Cheng/// to do this if tBfar is not used. 1547d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Chengbool ARMConstantIslands::UndoLRSpillRestore() { 1548d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng bool MadeChange = false; 1549d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng for (unsigned i = 0, e = PushPopMIs.size(); i != e; ++i) { 1550d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = PushPopMIs[i]; 1551815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson // First two operands are predicates. 155244bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng if (MI->getOpcode() == ARM::tPOP_RET && 1553815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson MI->getOperand(2).getReg() == ARM::PC && 1554815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson MI->getNumExplicitOperands() == 3) { 155525e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach // Create the new insn and copy the predicate from the old. 155625e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach BuildMI(MI->getParent(), MI->getDebugLoc(), TII->get(ARM::tBX_RET)) 155725e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach .addOperand(MI->getOperand(0)) 155825e6d48220330d17875d0ae0ad6a45597d5ac36cJim Grosbach .addOperand(MI->getOperand(1)); 155944bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng MI->eraseFromParent(); 156044bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng MadeChange = true; 1561d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng } 1562d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng } 1563d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return MadeChange; 1564d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 15655657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 1566a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Chengbool ARMConstantIslands::OptimizeThumb2Instructions(MachineFunction &MF) { 1567a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng bool MadeChange = false; 1568a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1569a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // Shrink ADR and LDR from constantpool. 1570a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng for (unsigned i = 0, e = CPUsers.size(); i != e; ++i) { 1571a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng CPUser &U = CPUsers[i]; 1572a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Opcode = U.MI->getOpcode(); 1573a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned NewOpc = 0; 1574a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Scale = 1; 1575a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Bits = 0; 1576a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng switch (Opcode) { 1577a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng default: break; 15786b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson case ARM::t2LEApcrel: 1579a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (isARMLowRegister(U.MI->getOperand(0).getReg())) { 1580a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng NewOpc = ARM::tLEApcrel; 1581a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Bits = 8; 1582a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Scale = 4; 1583a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1584a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng break; 1585a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng case ARM::t2LDRpci: 1586a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (isARMLowRegister(U.MI->getOperand(0).getReg())) { 1587a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng NewOpc = ARM::tLDRpci; 1588a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Bits = 8; 1589a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Scale = 4; 1590a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1591a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng break; 1592a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1593a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1594a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (!NewOpc) 1595a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng continue; 1596a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1597a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned UserOffset = GetOffsetOf(U.MI) + 4; 1598a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned MaxOffs = ((1 << Bits) - 1) * Scale; 1599a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // FIXME: Check if offset is multiple of scale if scale is not 4. 1600a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (CPEIsInRange(U.MI, UserOffset, U.CPEMI, MaxOffs, false, true)) { 1601a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng U.MI->setDesc(TII->get(NewOpc)); 1602a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MachineBasicBlock *MBB = U.MI->getParent(); 1603a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng BBSizes[MBB->getNumber()] -= 2; 1604a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng AdjustBBOffsetsAfter(MBB, -2); 1605a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng ++NumT2CPShrunk; 1606a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MadeChange = true; 1607a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1608a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1609a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1610a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MadeChange |= OptimizeThumb2Branches(MF); 161101dec0e545de18aadcd3911563a93d10a625be80Jim Grosbach MadeChange |= OptimizeThumb2JumpTables(MF); 1612a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng return MadeChange; 1613a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng} 1614a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1615a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Chengbool ARMConstantIslands::OptimizeThumb2Branches(MachineFunction &MF) { 161631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng bool MadeChange = false; 161731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 161831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng for (unsigned i = 0, e = ImmBranches.size(); i != e; ++i) { 161931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng ImmBranch &Br = ImmBranches[i]; 162031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Opcode = Br.MI->getOpcode(); 162131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned NewOpc = 0; 162231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Scale = 1; 162331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Bits = 0; 162431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng switch (Opcode) { 162531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng default: break; 162631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng case ARM::t2B: 162731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng NewOpc = ARM::tB; 162831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Bits = 11; 162931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Scale = 2; 163031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng break; 1631de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng case ARM::t2Bcc: { 163231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng NewOpc = ARM::tBcc; 163331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Bits = 8; 1634de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Scale = 2; 163531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng break; 163631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 1637de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1638de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (NewOpc) { 1639de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned MaxOffs = ((1 << (Bits-1))-1) * Scale; 1640de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MachineBasicBlock *DestBB = Br.MI->getOperand(0).getMBB(); 1641de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (BBIsInRange(Br.MI, DestBB, MaxOffs)) { 1642de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Br.MI->setDesc(TII->get(NewOpc)); 1643de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MachineBasicBlock *MBB = Br.MI->getParent(); 1644de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng BBSizes[MBB->getNumber()] -= 2; 1645de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng AdjustBBOffsetsAfter(MBB, -2); 1646de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng ++NumT2BrShrunk; 1647de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MadeChange = true; 1648de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1649de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1650de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng 1651de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Opcode = Br.MI->getOpcode(); 1652de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (Opcode != ARM::tBcc) 165331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng continue; 165431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 1655de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = 0; 1656de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned PredReg = 0; 1657de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng ARMCC::CondCodes Pred = llvm::getInstrPredicate(Br.MI, PredReg); 1658de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (Pred == ARMCC::EQ) 1659de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = ARM::tCBZ; 1660de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng else if (Pred == ARMCC::NE) 1661de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = ARM::tCBNZ; 1662de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (!NewOpc) 1663de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng continue; 166431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng MachineBasicBlock *DestBB = Br.MI->getOperand(0).getMBB(); 1665de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng // Check if the distance is within 126. Subtract starting offset by 2 1666de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng // because the cmp will be eliminated. 1667de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned BrOffset = GetOffsetOf(Br.MI) + 4 - 2; 1668de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned DestOffset = BBOffsets[DestBB->getNumber()]; 1669de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (BrOffset < DestOffset && (DestOffset - BrOffset) <= 126) { 16700539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MachineBasicBlock::iterator CmpMI = Br.MI; 16710539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng if (CmpMI != Br.MI->getParent()->begin()) { 16720539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng --CmpMI; 16730539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng if (CmpMI->getOpcode() == ARM::tCMPi8) { 16740539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng unsigned Reg = CmpMI->getOperand(0).getReg(); 16750539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng Pred = llvm::getInstrPredicate(CmpMI, PredReg); 16760539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng if (Pred == ARMCC::AL && 16770539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng CmpMI->getOperand(1).getImm() == 0 && 16780539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng isARMLowRegister(Reg)) { 16790539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MachineBasicBlock *MBB = Br.MI->getParent(); 16800539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MachineInstr *NewBR = 16810539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng BuildMI(*MBB, CmpMI, Br.MI->getDebugLoc(), TII->get(NewOpc)) 16820539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng .addReg(Reg).addMBB(DestBB,Br.MI->getOperand(0).getTargetFlags()); 16830539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng CmpMI->eraseFromParent(); 16840539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng Br.MI->eraseFromParent(); 16850539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng Br.MI = NewBR; 16860539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng BBSizes[MBB->getNumber()] -= 2; 16870539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng AdjustBBOffsetsAfter(MBB, -2); 16880539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng ++NumCBZ; 16890539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng MadeChange = true; 16900539c159fb6e3f8d09d4790d8d6a4615c26d3e98Evan Cheng } 1691de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1692de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 169331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 169431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 169531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 169631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng return MadeChange; 1697a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng} 1698a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1699a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng/// OptimizeThumb2JumpTables - Use tbb / tbh instructions to generate smaller 1700a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng/// jumptables when it's possible. 17015657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::OptimizeThumb2JumpTables(MachineFunction &MF) { 17025657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool MadeChange = false; 17035657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17045657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng // FIXME: After the tables are shrunk, can we get rid some of the 17055657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng // constantpool tables? 17061fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineJumpTableInfo *MJTI = MF.getJumpTableInfo(); 1707b1e803985d3378538ae9cff7eed4102c002d1e22Chris Lattner if (MJTI == 0) return false; 170826b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach 17095657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 17105657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned i = 0, e = T2JumpTables.size(); i != e; ++i) { 17115657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineInstr *MI = T2JumpTables[i]; 1712e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng const MCInstrDesc &MCID = MI->getDesc(); 1713e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng unsigned NumOps = MCID.getNumOperands(); 1714e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng unsigned JTOpIdx = NumOps - (MCID.isPredicable() ? 3 : 2); 17155657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineOperand JTOP = MI->getOperand(JTOpIdx); 17165657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned JTI = JTOP.getIndex(); 17175657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng assert(JTI < JT.size()); 17185657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17191fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach bool ByteOk = true; 17201fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach bool HalfWordOk = true; 172180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach unsigned JTOffset = GetOffsetOf(MI) + 4; 172280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 17235657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned j = 0, ee = JTBBs.size(); j != ee; ++j) { 17245657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *MBB = JTBBs[j]; 17255657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned DstOffset = BBOffsets[MBB->getNumber()]; 17268770f747a98194056805f1b7cbcb0b75a7633b87Evan Cheng // Negative offset is not ok. FIXME: We should change BB layout to make 17278770f747a98194056805f1b7cbcb0b75a7633b87Evan Cheng // sure all the branches are forward. 1728d26b14c34cbcee1448b86b524578fc51cc979023Evan Cheng if (ByteOk && (DstOffset - JTOffset) > ((1<<8)-1)*2) 17295657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng ByteOk = false; 173025f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned TBHLimit = ((1<<16)-1)*2; 173125f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng if (HalfWordOk && (DstOffset - JTOffset) > TBHLimit) 17325657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng HalfWordOk = false; 17335657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!ByteOk && !HalfWordOk) 17345657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 17355657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17365657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17375657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (ByteOk || HalfWordOk) { 17385657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 17395657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned BaseReg = MI->getOperand(0).getReg(); 17405657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool BaseRegKill = MI->getOperand(0).isKill(); 17415657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!BaseRegKill) 17425657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17435657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned IdxReg = MI->getOperand(1).getReg(); 17445657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool IdxRegKill = MI->getOperand(1).isKill(); 1745c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 1746c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // Scan backwards to find the instruction that defines the base 1747c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // register. Due to post-RA scheduling, we can't count on it 1748c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // immediately preceding the branch instruction. 17495657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock::iterator PrevI = MI; 1750c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineBasicBlock::iterator B = MBB->begin(); 1751c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach while (PrevI != B && !PrevI->definesRegister(BaseReg)) 1752c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach --PrevI; 1753c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 1754c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // If for some reason we didn't find it, we can't do anything, so 1755c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // just skip this one. 1756c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach if (!PrevI->definesRegister(BaseReg)) 17575657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17585657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 1759c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineInstr *AddrMI = PrevI; 17605657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool OptOk = true; 176126b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach // Examine the instruction that calculates the jumptable entry address. 1762c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // Make sure it only defines the base register and kills any uses 1763c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // other than the index register. 17645657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned k = 0, eee = AddrMI->getNumOperands(); k != eee; ++k) { 17655657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const MachineOperand &MO = AddrMI->getOperand(k); 17665657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!MO.isReg() || !MO.getReg()) 17675657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17685657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (MO.isDef() && MO.getReg() != BaseReg) { 17695657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng OptOk = false; 17705657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 17715657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17725657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (MO.isUse() && !MO.isKill() && MO.getReg() != IdxReg) { 17735657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng OptOk = false; 17745657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 17755657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17765657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17775657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!OptOk) 17785657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17795657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17806b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson // Now scan back again to find the tLEApcrel or t2LEApcrelJT instruction 1781c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // that gave us the initial base register definition. 1782c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach for (--PrevI; PrevI != B && !PrevI->definesRegister(BaseReg); --PrevI) 1783c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach ; 1784c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 17856b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson // The instruction should be a tLEApcrel or t2LEApcrelJT; we want 1786a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // to delete it as well. 1787c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineInstr *LeaMI = PrevI; 1788a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if ((LeaMI->getOpcode() != ARM::tLEApcrelJT && 17896b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson LeaMI->getOpcode() != ARM::t2LEApcrelJT) || 17905657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng LeaMI->getOperand(0).getReg() != BaseReg) 179125f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OptOk = false; 179225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 179325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng if (!OptOk) 179425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng continue; 179525f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 1796d092a87ba3f905a6801a0bdf816267329cf0391cJim Grosbach unsigned Opc = ByteOk ? ARM::t2TBB_JT : ARM::t2TBH_JT; 179725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MachineInstr *NewJTMI = BuildMI(MBB, MI->getDebugLoc(), TII->get(Opc)) 179825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addReg(IdxReg, getKillRegState(IdxRegKill)) 179925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addJumpTableIndex(JTI, JTOP.getTargetFlags()) 180025f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addImm(MI->getOperand(JTOpIdx+1).getImm()); 180125f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng // FIXME: Insert an "ALIGN" instruction to ensure the next instruction 180225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng // is 2-byte aligned. For now, asm printer will fix it up. 180325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned NewSize = TII->GetInstSizeInBytes(NewJTMI); 180425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned OrigSize = TII->GetInstSizeInBytes(AddrMI); 180525f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OrigSize += TII->GetInstSizeInBytes(LeaMI); 180625f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OrigSize += TII->GetInstSizeInBytes(MI); 180725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 180825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng AddrMI->eraseFromParent(); 180925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng LeaMI->eraseFromParent(); 181025f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MI->eraseFromParent(); 181125f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 181225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng int delta = OrigSize - NewSize; 181325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng BBSizes[MBB->getNumber()] -= delta; 181425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng AdjustBBOffsetsAfter(MBB, -delta); 181525f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 181625f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng ++NumTBs; 181725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MadeChange = true; 18185657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 18195657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 18205657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 18215657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return MadeChange; 18225657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng} 18231fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 18249249efe4c7451e83fb4c904fd7fcc8edfe08d815Jim Grosbach/// ReorderThumb2JumpTables - Adjust the function's block layout to ensure that 18259249efe4c7451e83fb4c904fd7fcc8edfe08d815Jim Grosbach/// jump tables always branch forwards, since that's what tbb and tbh need. 182680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbachbool ARMConstantIslands::ReorderThumb2JumpTables(MachineFunction &MF) { 182780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach bool MadeChange = false; 182880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 182980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineJumpTableInfo *MJTI = MF.getJumpTableInfo(); 1830b1e803985d3378538ae9cff7eed4102c002d1e22Chris Lattner if (MJTI == 0) return false; 183126b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach 183280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 183380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (unsigned i = 0, e = T2JumpTables.size(); i != e; ++i) { 183480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineInstr *MI = T2JumpTables[i]; 1835e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng const MCInstrDesc &MCID = MI->getDesc(); 1836e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng unsigned NumOps = MCID.getNumOperands(); 1837e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng unsigned JTOpIdx = NumOps - (MCID.isPredicable() ? 3 : 2); 183880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineOperand JTOP = MI->getOperand(JTOpIdx); 183980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach unsigned JTI = JTOP.getIndex(); 184080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach assert(JTI < JT.size()); 184180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 184280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // We prefer if target blocks for the jump table come after the jump 184380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // instruction so we can use TB[BH]. Loop through the target blocks 184480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // and try to adjust them such that that's true. 184508cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach int JTNumber = MI->getParent()->getNumber(); 184680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 184780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (unsigned j = 0, ee = JTBBs.size(); j != ee; ++j) { 184880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *MBB = JTBBs[j]; 184908cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach int DTNumber = MBB->getNumber(); 185080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 185108cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach if (DTNumber < JTNumber) { 185280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // The destination precedes the switch. Try to move the block forward 185380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // so we have a positive offset. 185480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *NewBB = 185580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach AdjustJTTargetBlockForward(MBB, MI->getParent()); 185680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach if (NewBB) 185700a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach MJTI->ReplaceMBBInJumpTable(JTI, JTBBs[j], NewBB); 185880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MadeChange = true; 185980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 186080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 186180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 186280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 186380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach return MadeChange; 186480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach} 186580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 18661fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim GrosbachMachineBasicBlock *ARMConstantIslands:: 18671fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim GrosbachAdjustJTTargetBlockForward(MachineBasicBlock *BB, MachineBasicBlock *JTBB) 18681fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach{ 18691fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineFunction &MF = *BB->getParent(); 18701fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 187103e2d44722c1ebd3953007db0579147b46efba18Jim Grosbach // If the destination block is terminated by an unconditional branch, 187280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // try to move it; otherwise, create a new block following the jump 187308cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // table that branches back to the actual target. This is a very simple 187408cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // heuristic. FIXME: We can definitely improve it. 187580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *TBB = 0, *FBB = 0; 187680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach SmallVector<MachineOperand, 4> Cond; 1877a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach SmallVector<MachineOperand, 4> CondPrior; 1878a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MachineFunction::iterator BBi = BB; 1879a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MachineFunction::iterator OldPrior = prior(BBi); 188000a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach 1881ca215e7804ca5d85e19e31850c3ba3d155624e89Jim Grosbach // If the block terminator isn't analyzable, don't try to move the block 1882a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach bool B = TII->AnalyzeBranch(*BB, TBB, FBB, Cond); 1883ca215e7804ca5d85e19e31850c3ba3d155624e89Jim Grosbach 1884a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach // If the block ends in an unconditional branch, move it. The prior block 1885a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach // has to have an analyzable terminator for us to move this one. Be paranoid 188608cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // and make sure we're not trying to move the entry block of the function. 1887a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach if (!B && Cond.empty() && BB != MF.begin() && 1888a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach !TII->AnalyzeBranch(*OldPrior, TBB, FBB, CondPrior)) { 188980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach BB->moveAfter(JTBB); 189080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach OldPrior->updateTerminator(); 189100a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach BB->updateTerminator(); 189208cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // Update numbering to account for the block being moved. 1893a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MF.RenumberBlocks(); 189480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach ++NumJTMoved; 189580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach return NULL; 189680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 18971fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 18981fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Create a new MBB for the code after the jump BB. 18991fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineBasicBlock *NewBB = 19001fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MF.CreateMachineBasicBlock(JTBB->getBasicBlock()); 19011fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineFunction::iterator MBBI = JTBB; ++MBBI; 19021fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MF.insert(MBBI, NewBB); 19031fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 19041fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Add an unconditional branch from NewBB to BB. 19051fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // There doesn't seem to be meaningful DebugInfo available; this doesn't 19061fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // correspond directly to anything in the source. 19071fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach assert (isThumb2 && "Adjusting for TB[BH] but not in Thumb2?"); 190851f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson BuildMI(NewBB, DebugLoc(), TII->get(ARM::t2B)).addMBB(BB) 190951f6a7abf27fc92c3d8904c2334feab8b498e8e9Owen Anderson .addImm(ARMCC::AL).addReg(0); 19101fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 191100a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach // Update internal data structures to account for the newly inserted MBB. 191200a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach MF.RenumberBlocks(NewBB); 191300a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach 19141fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Update the CFG. 19151fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach NewBB->addSuccessor(BB); 19161fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach JTBB->removeSuccessor(BB); 19171fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach JTBB->addSuccessor(NewBB); 19181fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 191980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach ++NumJTInserted; 19201fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach return NewBB; 19211fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach} 1922