ARMConstantIslandPass.cpp revision cd080249fc249a51d8b0021a651d8b9d4a4977e0
1a8e2989ece6dc46df59b0768184028257f913843Evan Cheng//===-- ARMConstantIslandPass.cpp - ARM constant islands --------*- C++ -*-===// 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" 18d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng#include "ARMAddressingModes.h" 19af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng#include "ARMMachineFunctionInfo.h" 20a8e2989ece6dc46df59b0768184028257f913843Evan Cheng#include "ARMInstrInfo.h" 21719510a178a910feb1db707140011c32a30992c4Evan Cheng#include "Thumb2InstrInfo.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. 319f1bbb9577a42cf7dc3079412f1dd7683e3a03665Evan Cheng AFI->initConstPoolEntryUId(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 371b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng DEBUG(errs() << '\n'; dumpBBs()); 372b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng 373a8e2989ece6dc46df59b0768184028257f913843Evan Cheng BBSizes.clear(); 37499c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets.clear(); 375a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.clear(); 376a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CPUsers.clear(); 377c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntries.clear(); 378af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng ImmBranches.clear(); 379c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng PushPopMIs.clear(); 3805657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng T2JumpTables.clear(); 381d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 382d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return MadeChange; 383a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 384a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 385a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// DoInitialPlacement - Perform the initial placement of the constant pool 386a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// entries. To start with, we put them all at the end of the function. 3875657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengvoid ARMConstantIslands::DoInitialPlacement(MachineFunction &MF, 3888494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson std::vector<MachineInstr*> &CPEMIs) { 389a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Create the basic block to hold the CPE's. 3905657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *BB = MF.CreateMachineBasicBlock(); 3915657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.push_back(BB); 3928494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 393a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add all of the constants from the constant pool to the end block, use an 394a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // identity mapping of CPI's to CPE's. 395a8e2989ece6dc46df59b0768184028257f913843Evan Cheng const std::vector<MachineConstantPoolEntry> &CPs = 3965657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.getConstantPool()->getConstants(); 3978494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 3985657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const TargetData &TD = *MF.getTarget().getTargetData(); 399a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned i = 0, e = CPs.size(); i != e; ++i) { 400777d2306b36816a53bc1ae1244c0dc7d998ae691Duncan Sands unsigned Size = TD.getTypeAllocSize(CPs[i].getType()); 401a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Verify that all constant pool entries are a multiple of 4 bytes. If not, 402a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // we would have to pad them out or something so that instructions stay 403a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // aligned. 404a8e2989ece6dc46df59b0768184028257f913843Evan Cheng assert((Size & 3) == 0 && "CP Entry not multiple of 4 bytes!"); 405a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineInstr *CPEMI = 406c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(BB, DebugLoc(), TII->get(ARM::CONSTPOOL_ENTRY)) 407c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner .addImm(i).addConstantPoolIndex(i).addImm(Size); 408a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CPEMIs.push_back(CPEMI); 409c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 410c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Add a new CPEntry, but no corresponding CPUser yet. 411c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng std::vector<CPEntry> CPEs; 412c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEs.push_back(CPEntry(CPEMI, i)); 413c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntries.push_back(CPEs); 414fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCPEs; 415893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Moved CPI#" << i << " to end of function as #" << i 416893e1c90a03a53cf13f73849324e83612688428aChris Lattner << "\n"); 417a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 418a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 419a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 42088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// BBHasFallthrough - Return true if the specified basic block can fallthrough 421a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// into the block immediately after it. 422a8e2989ece6dc46df59b0768184028257f913843Evan Chengstatic bool BBHasFallthrough(MachineBasicBlock *MBB) { 423a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Get the next machine basic block in the function. 424a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineFunction::iterator MBBI = MBB; 42518f30e6f5e80787808fe1455742452a5210afe07Jim Grosbach // Can't fall off end of function. 42618f30e6f5e80787808fe1455742452a5210afe07Jim Grosbach if (llvm::next(MBBI) == MBB->getParent()->end()) 427a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return false; 4288494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 4297896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineBasicBlock *NextBB = llvm::next(MBBI); 430a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::succ_iterator I = MBB->succ_begin(), 431a8e2989ece6dc46df59b0768184028257f913843Evan Cheng E = MBB->succ_end(); I != E; ++I) 432a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (*I == NextBB) 433a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return true; 4348494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 435a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return false; 436a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 437a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 438c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// findConstPoolEntry - Given the constpool index and CONSTPOOL_ENTRY MI, 439c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// look up the corresponding CPEntry. 440c99ef085b90b32952b484e8843fb66ad65215b61Evan ChengARMConstantIslands::CPEntry 441c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng*ARMConstantIslands::findConstPoolEntry(unsigned CPI, 442c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng const MachineInstr *CPEMI) { 443c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng std::vector<CPEntry> &CPEs = CPEntries[CPI]; 444c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Number of entries per constpool index should be small, just do a 445c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // linear search. 446c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng for (unsigned i = 0, e = CPEs.size(); i != e; ++i) { 447c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng if (CPEs[i].CPEMI == CPEMI) 448c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return &CPEs[i]; 449c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng } 450c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return NULL; 451c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng} 452c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 45380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// JumpTableFunctionScan - Do a scan of the function, building up 45480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// information about the sizes of each block and the locations of all 45580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach/// the jump tables. 45680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbachvoid ARMConstantIslands::JumpTableFunctionScan(MachineFunction &MF) { 45780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 45880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MBBI != E; ++MBBI) { 45980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock &MBB = *MBBI; 46080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 46180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 46208cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach I != E; ++I) 46308cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach if (I->getDesc().isBranch() && I->getOpcode() == ARM::t2BR_JT) 46408cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach T2JumpTables.push_back(I); 46580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 46680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach} 46780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 468a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// InitialFunctionScan - Do the initial scan of the function, building up 469a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// information about the sizes of each block, the location of all the water, 470a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// and finding all of the constant pool users. 4715657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengvoid ARMConstantIslands::InitialFunctionScan(MachineFunction &MF, 472e03cff6812ac41598e2bca7854985dc821a07f44Evan Cheng const std::vector<MachineInstr*> &CPEMIs) { 4734d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // First thing, see if the function has any inline assembly in it. If so, 4744d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // we have to be conservative about alignment assumptions, as we don't 4754d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // know for sure the size of any instructions in the inline assembly. 4764d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 4774d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach MBBI != E; ++MBBI) { 4784d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach MachineBasicBlock &MBB = *MBBI; 4794d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 4804d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach I != E; ++I) 4814d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach if (I->getOpcode() == ARM::INLINEASM) 4824d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach HasInlineAsm = true; 4834d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach } 4844d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach 4854d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach // Now go back through the instructions and build up our data structures 48699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned Offset = 0; 4875657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); 488a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MBBI != E; ++MBBI) { 489a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock &MBB = *MBBI; 4908494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 491a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // If this block doesn't fall through into the next MBB, then this is 492a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // 'water' that a constant pool island could be placed. 493a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (!BBHasFallthrough(&MBB)) 494a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.push_back(&MBB); 4958494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 496a8e2989ece6dc46df59b0768184028257f913843Evan Cheng unsigned MBBSize = 0; 497a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); 498a8e2989ece6dc46df59b0768184028257f913843Evan Cheng I != E; ++I) { 4999cfcfeb24bf7182d40d8e8a54e350451b67a1136Jim Grosbach if (I->isDebugValue()) 5009cfcfeb24bf7182d40d8e8a54e350451b67a1136Jim Grosbach continue; 501a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add instruction size to MBBSize. 50252e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray MBBSize += TII->GetInstSizeInBytes(I); 503a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 504af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng int Opc = I->getOpcode(); 505749c6f6b5ed301c84aac562e414486549d7b98ebChris Lattner if (I->getDesc().isBranch()) { 506af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng bool isCond = false; 507af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng unsigned Bits = 0; 508af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng unsigned Scale = 1; 509af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng int UOpc = Opc; 510af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng switch (Opc) { 5115657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng default: 5125657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; // Ignore other JT branches 5138593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen case ARM::tBR_JTr: 51466ac53165e17b7c76b8c69e57bde623d44ec492eEvan Cheng // A Thumb1 table jump may involve padding; for the offsets to 5158593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // be right, functions containing these must be 4-byte aligned. 516b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng // tBR_JTr expands to a mov pc followed by .align 2 and then the jump 517b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng // table entries. So this code checks whether offset of tBR_JTr + 2 5188086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // is aligned. That is held in Offset+MBBSize, which already has 5198086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // 2 added in for the size of the mov pc instruction. 5207d7dab02783fb4f1f5d0cf274c52a4fb059bfbeaChris Lattner MF.EnsureAlignment(2U); 5218086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen if ((Offset+MBBSize)%4 != 0 || HasInlineAsm) 5225657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng // FIXME: Add a pseudo ALIGN instruction instead. 5238593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen MBBSize += 2; // padding 5248593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen continue; // Does not get an entry in ImmBranches 5255657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng case ARM::t2BR_JT: 5265657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng T2JumpTables.push_back(I); 5275657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; // Does not get an entry in ImmBranches 528af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::Bcc: 529af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng isCond = true; 530af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng UOpc = ARM::B; 531af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // Fallthrough 532af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::B: 533af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 24; 534af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 4; 535af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 536af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::tBcc: 537af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng isCond = true; 538af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng UOpc = ARM::tB; 539af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 8; 540af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 2; 541af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 542af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng case ARM::tB: 543af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Bits = 11; 544af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Scale = 2; 545af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng break; 5465e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::t2Bcc: 5475e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin isCond = true; 5485e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin UOpc = ARM::t2B; 5495e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Bits = 20; 5505e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Scale = 2; 5515e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin break; 5525e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::t2B: 5535e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Bits = 24; 5545e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin Scale = 2; 5555e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin break; 556af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng } 557b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng 558b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng // Record this immediate branch. 559bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng unsigned MaxOffs = ((1 << (Bits-1))-1) * Scale; 560b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng ImmBranches.push_back(ImmBranch(I, MaxOffs, isCond, UOpc)); 561af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng } 562af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 563d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng if (Opc == ARM::tPUSH || Opc == ARM::tPOP_RET) 564d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng PushPopMIs.push_back(I); 565d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 566d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (Opc == ARM::CONSTPOOL_ENTRY) 567d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng continue; 568d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 569a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Scan the instructions for constant pool operands. 570a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned op = 0, e = I->getNumOperands(); op != e; ++op) 571d735b8019b0f297d7c14b55adcd887af24d8e602Dan Gohman if (I->getOperand(op).isCPI()) { 572a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // We found one. The addressing mode tells us the max displacement 573a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // from the PC that this instruction permits. 5748494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 575a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Basic size info comes from the TSFlags field. 576b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng unsigned Bits = 0; 577b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng unsigned Scale = 1; 5785d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool NegOk = false; 579d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool IsSoImm = false; 580d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 581d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng switch (Opc) { 5828494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson default: 583c23197a26f34f559ea9797de51e187087c039c42Torok Edwin llvm_unreachable("Unknown addressing mode for CP reference!"); 584a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 585d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 586d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // Taking the address of a CP entry. 587d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::LEApcrel: 588d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // This takes a SoImm, which is 8 bit immediate rotated. We'll 589d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // pretend the maximum offset is 255 * 4. Since each instruction 590dec6de92d1425c88f319179fb4a0b0a23f781df9Jim Grosbach // 4 byte wide, this is always correct. We'll check for other 591d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // displacements that fits in a SoImm as well. 592d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 8; 593d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; 5945d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng NegOk = true; 595d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng IsSoImm = true; 596a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 5976b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson case ARM::t2LEApcrel: 598d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 12; 5995d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng NegOk = true; 600a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 601d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::tLEApcrel: 602b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Bits = 8; 603d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; 604a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 605d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 6063e5561247202bae994dd259a2d8dc4eff8f799f3Jim Grosbach case ARM::LDRi12: 607d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::LDRcp: 608eb6779c5b98383e33542207f062102e79263df16Owen Anderson case ARM::t2LDRi12: 609eb6779c5b98383e33542207f062102e79263df16Owen Anderson case ARM::t2LDRHi12: 610eb6779c5b98383e33542207f062102e79263df16Owen Anderson case ARM::t2LDRBi12: 611eb6779c5b98383e33542207f062102e79263df16Owen Anderson case ARM::t2LDRSHi12: 612eb6779c5b98383e33542207f062102e79263df16Owen Anderson case ARM::t2LDRSBi12: 613d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 12; // +-offset_12 614d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng NegOk = true; 615a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 616d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 617d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng case ARM::tLDRpci: 618b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Bits = 8; 619b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng Scale = 4; // +(offset_8*4) 620012f2d97b78e4eb9128f1d491f2c177768dbe527Evan Cheng break; 621d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng 622e5165490b7ba24bb2f3043399e0d60e7f3bcf8a5Jim Grosbach case ARM::VLDRD: 623e5165490b7ba24bb2f3043399e0d60e7f3bcf8a5Jim Grosbach case ARM::VLDRS: 624d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Bits = 8; 625d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng Scale = 4; // +-(offset_8*4) 626d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng NegOk = true; 627055b0310f862b91f33699037ce67d3ab8137c20cEvan Cheng break; 628a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 629b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng 630a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Remember that this is a user of a CP entry. 6318aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner unsigned CPI = I->getOperand(op).getIndex(); 632c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineInstr *CPEMI = CPEMIs[CPI]; 63331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned MaxOffs = ((1 << Bits)-1) * Scale; 634d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng CPUsers.push_back(CPUser(I, CPEMI, MaxOffs, NegOk, IsSoImm)); 635c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 636c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Increment corresponding CPEntry reference count. 637c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPEntry *CPE = findConstPoolEntry(CPI, CPEMI); 638c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng assert(CPE && "Cannot find a corresponding CPEntry!"); 639c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng CPE->RefCount++; 6408494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 641a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Instructions can only use one CP entry, don't bother scanning the 642a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // rest of the operands. 643a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 644a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 645a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 6462021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng 6478593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // In thumb mode, if this block is a constpool island, we may need padding 6488593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // so it's aligned on 4 byte boundary. 649b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (isThumb && 65005cc424082f797c5820b19f29f398c9cce9b9928Evan Cheng !MBB.empty() && 6518593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen MBB.begin()->getOpcode() == ARM::CONSTPOOL_ENTRY && 6524d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach ((Offset%4) != 0 || HasInlineAsm)) 6532021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng MBBSize += 2; 6542021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng 655a8e2989ece6dc46df59b0768184028257f913843Evan Cheng BBSizes.push_back(MBBSize); 65699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets.push_back(Offset); 65799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen Offset += MBBSize; 658a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 659a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 660a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 661a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// GetOffsetOf - Return the current offset of the specified machine instruction 662a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// from the start of the function. This offset changes as stuff is moved 663a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// around inside the function. 664a8e2989ece6dc46df59b0768184028257f913843Evan Chengunsigned ARMConstantIslands::GetOffsetOf(MachineInstr *MI) const { 665a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 6668494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 667a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // The offset is composed of two things: the sum of the sizes of all MBB's 668a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // before this instruction's block, and the offset from the start of the block 669a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // it is in. 67099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned Offset = BBOffsets[MBB->getNumber()]; 671a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 6728593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // If we're looking for a CONSTPOOL_ENTRY in Thumb, see if this block has 6738593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // alignment padding, and compensate if so. 6748494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson if (isThumb && 6758494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MI->getOpcode() == ARM::CONSTPOOL_ENTRY && 6764d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach (Offset%4 != 0 || HasInlineAsm)) 6778593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen Offset += 2; 6788593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 679a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Sum instructions before MI in MBB. 680a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (MachineBasicBlock::iterator I = MBB->begin(); ; ++I) { 681a8e2989ece6dc46df59b0768184028257f913843Evan Cheng assert(I != MBB->end() && "Didn't find MI in its own basic block?"); 682a8e2989ece6dc46df59b0768184028257f913843Evan Cheng if (&*I == MI) return Offset; 68352e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray Offset += TII->GetInstSizeInBytes(I); 684a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 685a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 686a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 687a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// CompareMBBNumbers - Little predicate function to sort the WaterList by MBB 688a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// ID. 689a8e2989ece6dc46df59b0768184028257f913843Evan Chengstatic bool CompareMBBNumbers(const MachineBasicBlock *LHS, 690a8e2989ece6dc46df59b0768184028257f913843Evan Cheng const MachineBasicBlock *RHS) { 691a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return LHS->getNumber() < RHS->getNumber(); 692a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 693a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 694a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// UpdateForInsertedWaterBlock - When a block is newly inserted into the 695a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// machine function, it upsets all of the block numbers. Renumber the blocks 696a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// and update the arrays that parallel this numbering. 697a8e2989ece6dc46df59b0768184028257f913843Evan Chengvoid ARMConstantIslands::UpdateForInsertedWaterBlock(MachineBasicBlock *NewBB) { 698a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Renumber the MBB's to keep them consequtive. 699a8e2989ece6dc46df59b0768184028257f913843Evan Cheng NewBB->getParent()->RenumberBlocks(NewBB); 7008494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 701a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Insert a size into BBSizes to align it properly with the (newly 702a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // renumbered) block numbers. 703a8e2989ece6dc46df59b0768184028257f913843Evan Cheng BBSizes.insert(BBSizes.begin()+NewBB->getNumber(), 0); 70499c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 70599c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // Likewise for BBOffsets. 70699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets.insert(BBOffsets.begin()+NewBB->getNumber(), 0); 7078494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 7088494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // Next, update WaterList. Specifically, we need to add NewMBB as having 709a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // available water after it. 710034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson water_iterator IP = 711a8e2989ece6dc46df59b0768184028257f913843Evan Cheng std::lower_bound(WaterList.begin(), WaterList.end(), NewBB, 712a8e2989ece6dc46df59b0768184028257f913843Evan Cheng CompareMBBNumbers); 713a8e2989ece6dc46df59b0768184028257f913843Evan Cheng WaterList.insert(IP, NewBB); 714a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 715a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 716a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 717a8e2989ece6dc46df59b0768184028257f913843Evan Cheng/// Split the basic block containing MI into two blocks, which are joined by 718b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson/// an unconditional branch. Update data structures and renumber blocks to 7190c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng/// account for this change and returns the newly created block. 7200c61584d05894a5543f690803191a8b0da05b8fcEvan ChengMachineBasicBlock *ARMConstantIslands::SplitBlockBeforeInstr(MachineInstr *MI) { 721a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock *OrigBB = MI->getParent(); 7228e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MachineFunction &MF = *OrigBB->getParent(); 723a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 724a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Create a new MBB for the code after the OrigBB. 7258494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MachineBasicBlock *NewBB = 7268494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson MF.CreateMachineBasicBlock(OrigBB->getBasicBlock()); 727a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineFunction::iterator MBBI = OrigBB; ++MBBI; 7288e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MF.insert(MBBI, NewBB); 7298494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 730a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Splice the instructions starting with MI over to NewBB. 731a8e2989ece6dc46df59b0768184028257f913843Evan Cheng NewBB->splice(NewBB->end(), OrigBB, MI, OrigBB->end()); 7328494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 733a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Add an unconditional branch from OrigBB to NewBB. 734a9b8b8d62c67e96bc4dc2ed25298c539102f8638Evan Cheng // Note the new unconditional branch is not being recorded. 735b67284057ee130114055309eabe0bcd1af13777dDale Johannesen // There doesn't seem to be meaningful DebugInfo available; this doesn't 736b67284057ee130114055309eabe0bcd1af13777dDale Johannesen // correspond to anything in the source. 73758541fd62707b6856beee3db9e254b0110607bb1Evan Cheng unsigned Opc = isThumb ? (isThumb2 ? ARM::t2B : ARM::tB) : ARM::B; 738c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(OrigBB, DebugLoc(), TII->get(Opc)).addMBB(NewBB); 739fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumSplit; 7408494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 741a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Update the CFG. All succs of OrigBB are now succs of NewBB. 742a8e2989ece6dc46df59b0768184028257f913843Evan Cheng while (!OrigBB->succ_empty()) { 743a8e2989ece6dc46df59b0768184028257f913843Evan Cheng MachineBasicBlock *Succ = *OrigBB->succ_begin(); 744a8e2989ece6dc46df59b0768184028257f913843Evan Cheng OrigBB->removeSuccessor(Succ); 745a8e2989ece6dc46df59b0768184028257f913843Evan Cheng NewBB->addSuccessor(Succ); 7468494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 747a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // This pass should be run after register allocation, so there should be no 748a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // PHI nodes to update. 749518bb53485df640d7b7e3f6b0544099020c42aa7Chris Lattner assert((Succ->empty() || !Succ->begin()->isPHI()) 750a8e2989ece6dc46df59b0768184028257f913843Evan Cheng && "PHI nodes should be eliminated by now!"); 751a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 7528494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 753a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // OrigBB branches to NewBB. 754a8e2989ece6dc46df59b0768184028257f913843Evan Cheng OrigBB->addSuccessor(NewBB); 7558494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 756a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Update internal data structures to account for the newly inserted MBB. 75788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // This is almost the same as UpdateForInsertedWaterBlock, except that 75888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // the Water goes after OrigBB, not NewBB. 7598e5f2c6f65841542e2a7092553fe42a00048e4c7Dan Gohman MF.RenumberBlocks(NewBB); 7608494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 76188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Insert a size into BBSizes to align it properly with the (newly 76288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // renumbered) block numbers. 76388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen BBSizes.insert(BBSizes.begin()+NewBB->getNumber(), 0); 7648494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 76599c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // Likewise for BBOffsets. 76699c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets.insert(BBOffsets.begin()+NewBB->getNumber(), 0); 76799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 7688494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // Next, update WaterList. Specifically, we need to add OrigMBB as having 76988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // available water after it (but not if it's already there, which happens 77088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // when splitting before a conditional branch that is followed by an 77188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // unconditional branch - in that case we want to insert NewBB). 772034de5f65f9139954cb01d94eaebbaefd294946eBob Wilson water_iterator IP = 77388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen std::lower_bound(WaterList.begin(), WaterList.end(), OrigBB, 77488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen CompareMBBNumbers); 77588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen MachineBasicBlock* WaterBB = *IP; 77688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (WaterBB == OrigBB) 7777896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner WaterList.insert(llvm::next(IP), NewBB); 77888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen else 77988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen WaterList.insert(IP, OrigBB); 780b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(OrigBB); 78188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 78299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned OrigBBI = OrigBB->getNumber(); 78399c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned NewBBI = NewBB->getNumber(); 7848494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 78525f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng int delta = isThumb1 ? 2 : 4; 7868086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 7878086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // Figure out how large the OrigBB is. As the first half of the original 7888086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // block, it cannot contain a tablejump. The size includes 7898086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // the new jump we added. (It should be possible to do this without 7908086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // recounting everything, but it's very confusing, and this is rarely 7918086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // executed.) 7928086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen unsigned OrigBBSize = 0; 7938086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen for (MachineBasicBlock::iterator I = OrigBB->begin(), E = OrigBB->end(); 7948086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen I != E; ++I) 7958086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen OrigBBSize += TII->GetInstSizeInBytes(I); 7968086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen BBSizes[OrigBBI] = OrigBBSize; 79799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 79899c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // ...and adjust BBOffsets for NewBB accordingly. 79999c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets[NewBBI] = BBOffsets[OrigBBI] + BBSizes[OrigBBI]; 80099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 8018086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // Figure out how large the NewMBB is. As the second half of the original 8028086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // block, it may contain a tablejump. 8038086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen unsigned NewBBSize = 0; 8048086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen for (MachineBasicBlock::iterator I = NewBB->begin(), E = NewBB->end(); 8058086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen I != E; ++I) 8068086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen NewBBSize += TII->GetInstSizeInBytes(I); 8078086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // Set the size of NewBB in BBSizes. It does not include any padding now. 8088086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen BBSizes[NewBBI] = NewBBSize; 8098086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 8108086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen MachineInstr* ThumbJTMI = prior(NewBB->end()); 8118086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen if (ThumbJTMI->getOpcode() == ARM::tBR_JTr) { 8128086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // We've added another 2-byte instruction before this tablejump, which 8138086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // means we will always need padding if we didn't before, and vice versa. 8148086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 8158086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // The original offset of the jump instruction was: 8168086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen unsigned OrigOffset = BBOffsets[OrigBBI] + BBSizes[OrigBBI] - delta; 8178086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen if (OrigOffset%4 == 0) { 8188086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // We had padding before and now we don't. No net change in code size. 8198086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen delta = 0; 8208086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen } else { 8218086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // We didn't have padding before and now we do. 8228086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen BBSizes[NewBBI] += 2; 8238086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen delta = 4; 8248086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen } 8258086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen } 8268086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen 82799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // All BBOffsets following these blocks must be modified. 8288086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen if (delta) 8298086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen AdjustBBOffsetsAfter(NewBB, delta); 8300c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng 8310c61584d05894a5543f690803191a8b0da05b8fcEvan Cheng return NewBB; 832a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 833a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 8348593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// OffsetIsInRange - Checks whether UserOffset (the location of a constant pool 8358494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson/// reference) is within MaxDisp of TrialOffset (a proposed location of a 8368593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen/// constant pool entry). 8378494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilsonbool ARMConstantIslands::OffsetIsInRange(unsigned UserOffset, 838d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng unsigned TrialOffset, unsigned MaxDisp, 839d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng bool NegativeOK, bool IsSoImm) { 8408494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // On Thumb offsets==2 mod 4 are rounded down by the hardware for 8418494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson // purposes of the displacement computation; compensate for that here. 8428593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Effectively, the valid range of displacements is 2 bytes smaller for such 8438593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // references. 84431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned TotalAdj = 0; 84531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb && UserOffset%4 !=0) { 8468593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen UserOffset -= 2; 84731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng TotalAdj = 2; 84831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 8498593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // CPEs will be rounded up to a multiple of 4. 85031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb && TrialOffset%4 != 0) { 8518593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen TrialOffset += 2; 85231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng TotalAdj += 2; 85331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 85431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 85531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // In Thumb2 mode, later branch adjustments can shift instructions up and 85631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // cause alignment change. In the worst case scenario this can cause the 85731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // user's effective address to be subtracted by 2 and the CPE's address to 85831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng // be plus 2. 85931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng if (isThumb2 && TotalAdj != 4) 86031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng MaxDisp -= (4 - TotalAdj); 8618593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 86299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen if (UserOffset <= TrialOffset) { 86399c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen // User before the Trial. 864d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (TrialOffset - UserOffset <= MaxDisp) 865d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return true; 86640efc251cd7a52dd2375ec95ee38b1be4572178fEvan Cheng // FIXME: Make use full range of soimm values. 86799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen } else if (NegativeOK) { 868d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (UserOffset - TrialOffset <= MaxDisp) 869d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return true; 87040efc251cd7a52dd2375ec95ee38b1be4572178fEvan Cheng // FIXME: Make use full range of soimm values. 87199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen } 87299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen return false; 87399c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen} 87499c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 87588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// WaterIsInRange - Returns true if a CPE placed after the specified 87688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// Water (a basic block) will be in range for the specific MI. 87788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 87888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesenbool ARMConstantIslands::WaterIsInRange(unsigned UserOffset, 8795d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng MachineBasicBlock* Water, CPUser &U) { 8805d9c4b60204d741c213456e21b87e9af6a3dc627Dale Johannesen unsigned MaxDisp = U.MaxDisp; 8818494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson unsigned CPEOffset = BBOffsets[Water->getNumber()] + 88288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen BBSizes[Water->getNumber()]; 88388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 884d959aa421a8d14fc5aad29141f816db8f4362c7fDale Johannesen // If the CPE is to be inserted before the instruction, that will raise 885af4b7352193e4a024d4a4e87cac1ba1589e4de57Bob Wilson // the offset of the instruction. 886d959aa421a8d14fc5aad29141f816db8f4362c7fDale Johannesen if (CPEOffset < UserOffset) 8875d9c4b60204d741c213456e21b87e9af6a3dc627Dale Johannesen UserOffset += U.CPEMI->getOperand(2).getImm(); 888d959aa421a8d14fc5aad29141f816db8f4362c7fDale Johannesen 889d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return OffsetIsInRange(UserOffset, CPEOffset, MaxDisp, U.NegOk, U.IsSoImm); 89088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen} 89188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 89288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// CPEIsInRange - Returns true if the distance between specific MI and 893c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng/// specific ConstPool entry instruction can fit in MI's displacement field. 89488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesenbool ARMConstantIslands::CPEIsInRange(MachineInstr *MI, unsigned UserOffset, 8955d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng MachineInstr *CPEMI, unsigned MaxDisp, 8965d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng bool NegOk, bool DoDump) { 8978593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen unsigned CPEOffset = GetOffsetOf(CPEMI); 8984d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach assert((CPEOffset%4 == 0 || HasInlineAsm) && "Misaligned CPE"); 8992021abe154e3cac523755b74fc5e62a2c9dad1fcEvan Cheng 90088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (DoDump) { 901705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << "User of CPE#" << CPEMI->getOperand(0).getImm() 902705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " max delta=" << MaxDisp 903705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " insn address=" << UserOffset 904705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " CPE address=" << CPEOffset 905705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " offset=" << int(CPEOffset-UserOffset) << "\t" << *MI); 90688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 907a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 9085d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng return OffsetIsInRange(UserOffset, CPEOffset, MaxDisp, NegOk); 909c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng} 910c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng 911d1e7d9a88b5f4fa5e9a85affc4599c650c591ffbEvan Cheng#ifndef NDEBUG 912c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// BBIsJumpedOver - Return true of the specified basic block's only predecessor 913c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng/// unconditionally branches to its only successor. 914c99ef085b90b32952b484e8843fb66ad65215b61Evan Chengstatic bool BBIsJumpedOver(MachineBasicBlock *MBB) { 915c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng if (MBB->pred_size() != 1 || MBB->succ_size() != 1) 916c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return false; 917c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 918c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineBasicBlock *Succ = *MBB->succ_begin(); 919c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineBasicBlock *Pred = *MBB->pred_begin(); 920c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng MachineInstr *PredMI = &Pred->back(); 9215e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin if (PredMI->getOpcode() == ARM::B || PredMI->getOpcode() == ARM::tB 9225e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin || PredMI->getOpcode() == ARM::t2B) 923c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return PredMI->getOperand(0).getMBB() == Succ; 924c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng return false; 925c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng} 926d1e7d9a88b5f4fa5e9a85affc4599c650c591ffbEvan Cheng#endif // NDEBUG 927c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 9288494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilsonvoid ARMConstantIslands::AdjustBBOffsetsAfter(MachineBasicBlock *BB, 9298593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen int delta) { 9307896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineFunction::iterator MBBI = BB; MBBI = llvm::next(MBBI); 931d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng for(unsigned i = BB->getNumber()+1, e = BB->getParent()->getNumBlockIDs(); 932d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng i < e; ++i) { 93399c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen BBOffsets[i] += delta; 9348593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // If some existing blocks have padding, adjust the padding as needed, a 9358593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // bit tricky. delta can be negative so don't use % on that. 936d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (!isThumb) 937d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng continue; 938d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng MachineBasicBlock *MBB = MBBI; 9394d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach if (!MBB->empty() && !HasInlineAsm) { 940d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // Constant pool entries require padding. 941d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (MBB->begin()->getOpcode() == ARM::CONSTPOOL_ENTRY) { 9424a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng unsigned OldOffset = BBOffsets[i] - delta; 9434a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng if ((OldOffset%4) == 0 && (BBOffsets[i]%4) != 0) { 944d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // add new padding 945d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng BBSizes[i] += 2; 946d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta += 2; 9474a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng } else if ((OldOffset%4) != 0 && (BBOffsets[i]%4) == 0) { 948d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // remove existing padding 9494a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng BBSizes[i] -= 2; 950d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta -= 2; 9518593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 952d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng } 953d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // Thumb1 jump tables require padding. They should be at the end; 954d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // following unconditional branches are removed by AnalyzeBranch. 955b1c857bb7b3d7bc187de4e97439eb212a8604bf0Evan Cheng // tBR_JTr expands to a mov pc followed by .align 2 and then the jump 9568086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // table entries. So this code checks whether offset of tBR_JTr 9578086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // is aligned; if it is, the offset of the jump table following the 9588086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen // instruction will not be aligned, and we need padding. 959789476240d6b6f8ad9366cadf790a82bd41bb0b3Evan Cheng MachineInstr *ThumbJTMI = prior(MBB->end()); 96066ac53165e17b7c76b8c69e57bde623d44ec492eEvan Cheng if (ThumbJTMI->getOpcode() == ARM::tBR_JTr) { 9618086d5800dbe8cc392ce217adccfaca915858aedDale Johannesen unsigned NewMIOffset = GetOffsetOf(ThumbJTMI); 9624a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng unsigned OldMIOffset = NewMIOffset - delta; 9634a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng if ((OldMIOffset%4) == 0 && (NewMIOffset%4) != 0) { 964d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // remove existing padding 965d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng BBSizes[i] -= 2; 966d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta -= 2; 9674a8ea215e69e9ca19c8acf1c236b73860188a023Evan Cheng } else if ((OldMIOffset%4) != 0 && (NewMIOffset%4) == 0) { 968d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // add new padding 969d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng BBSizes[i] += 2; 970d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng delta += 2; 9718593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 9728593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 973d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng if (delta==0) 974d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng return; 9758593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 9767896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MBBI = llvm::next(MBBI); 9778593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 97899c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen} 97999c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen 98088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// DecrementOldEntry - find the constant pool entry with index CPI 98188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// and instruction CPEMI, and decrement its refcount. If the refcount 9828494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson/// becomes 0 remove the entry and instruction. Returns true if we removed 98388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// the entry, false if we didn't. 984b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng 985ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Chengbool ARMConstantIslands::DecrementOldEntry(unsigned CPI, MachineInstr *CPEMI) { 986c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng // Find the old entry. Eliminate it if it is no longer used. 987ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng CPEntry *CPE = findConstPoolEntry(CPI, CPEMI); 988ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng assert(CPE && "Unexpected!"); 989ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (--CPE->RefCount == 0) { 990ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng RemoveDeadCPEMI(CPEMI); 991ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng CPE->CPEMI = NULL; 992fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman --NumCPEs; 99388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return true; 99488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 99588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return false; 99688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen} 99788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 99888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// LookForCPEntryInRange - see if the currently referenced CPE is in range; 99988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// if not, see if an in-range clone of the CPE is in range, and if so, 100088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// change the data structures so the user references the clone. Returns: 100188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// 0 = no existing entry found 100288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// 1 = entry found, and there were no code insertions or deletions 100388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// 2 = entry found, and there were code insertions or deletions 100488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesenint ARMConstantIslands::LookForExistingCPEntry(CPUser& U, unsigned UserOffset) 100588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen{ 100688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen MachineInstr *UserMI = U.MI; 100788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen MachineInstr *CPEMI = U.CPEMI; 100888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 100988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Check to see if the CPE is already in-range. 10105d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng if (CPEIsInRange(UserMI, UserOffset, CPEMI, U.MaxDisp, U.NegOk, true)) { 1011893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "In range\n"); 101288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return 1; 1013c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng } 1014c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 101588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // No. Look for previously created clones of the CPE that are in range. 10168aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner unsigned CPI = CPEMI->getOperand(1).getIndex(); 101788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen std::vector<CPEntry> &CPEs = CPEntries[CPI]; 101888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen for (unsigned i = 0, e = CPEs.size(); i != e; ++i) { 101988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // We already tried this one 102088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (CPEs[i].CPEMI == CPEMI) 102188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen continue; 102288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Removing CPEs can leave empty entries, skip 102388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen if (CPEs[i].CPEMI == NULL) 102488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen continue; 10255d8f1cae76e4e424bf3b4392eddb3f4dbf38662aEvan Cheng if (CPEIsInRange(UserMI, UserOffset, CPEs[i].CPEMI, U.MaxDisp, U.NegOk)) { 1026893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Replacing CPE#" << CPI << " with CPE#" 1027893e1c90a03a53cf13f73849324e83612688428aChris Lattner << CPEs[i].CPI << "\n"); 102888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Point the CPUser node to the replacement 102988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen U.CPEMI = CPEs[i].CPEMI; 103088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Change the CPI in the instruction operand to refer to the clone. 103188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen for (unsigned j = 0, e = UserMI->getNumOperands(); j != e; ++j) 1032d735b8019b0f297d7c14b55adcd887af24d8e602Dan Gohman if (UserMI->getOperand(j).isCPI()) { 10338aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner UserMI->getOperand(j).setIndex(CPEs[i].CPI); 103488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen break; 103588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 103688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Adjust the refcount of the clone... 103788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen CPEs[i].RefCount++; 103888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // ...and the original. If we didn't remove the old entry, none of the 103988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // addresses changed, so we don't need another pass. 1040ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng return DecrementOldEntry(CPI, CPEMI) ? 2 : 1; 104188e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 104288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 104388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen return 0; 104488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen} 104588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 1046f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen/// getUnconditionalBrDisp - Returns the maximum displacement that can fit in 1047f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen/// the specific unconditional branch instruction. 1048f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesenstatic inline unsigned getUnconditionalBrDisp(int Opc) { 10495e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin switch (Opc) { 10505e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::tB: 10515e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin return ((1<<10)-1)*2; 10525e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin case ARM::t2B: 10535e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin return ((1<<23)-1)*2; 10545e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin default: 10555e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin break; 10565e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin } 1057764ab52dd80310a205c9888bf166d09dab858f90Jim Grosbach 10585e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin return ((1<<23)-1)*4; 1059f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen} 1060f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen 1061b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson/// LookForWater - Look for an existing entry in the WaterList in which 1062b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// we can place the CPE referenced from U so it's within range of U's MI. 1063b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson/// Returns true if found, false if not. If it returns true, WaterIter 1064f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// is set to the WaterList entry. For Thumb, prefer water that will not 1065f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// introduce padding to water that will. To ensure that this pass 1066f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// terminates, the CPE location for a particular CPUser is only allowed to 1067f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// move to a lower address, so search backward from the end of the list and 1068f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson/// prefer the first water that is in range. 1069b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesenbool ARMConstantIslands::LookForWater(CPUser &U, unsigned UserOffset, 1070b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson water_iterator &WaterIter) { 10713b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson if (WaterList.empty()) 10723b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson return false; 10733b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson 107432c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson bool FoundWaterThatWouldPad = false; 107532c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson water_iterator IPThatWouldPad; 10763b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson for (water_iterator IP = prior(WaterList.end()), 10773b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson B = WaterList.begin();; --IP) { 10783b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson MachineBasicBlock* WaterBB = *IP; 1079b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Check if water is in range and is either at a lower address than the 1080b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // current "high water mark" or a new water block that was created since 1081b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // the previous iteration by inserting an unconditional branch. In the 1082b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // latter case, we want to allow resetting the high water mark back to 1083b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // this new water since we haven't seen it before. Inserting branches 1084b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // should be relatively uncommon and when it does happen, we want to be 1085b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // sure to take advantage of it for all the CPEs near that block, so that 1086b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // we don't insert more branches than necessary. 1087b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (WaterIsInRange(UserOffset, WaterBB, U) && 1088b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson (WaterBB->getNumber() < U.HighWaterMark->getNumber() || 1089b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.count(WaterBB))) { 10903b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson unsigned WBBId = WaterBB->getNumber(); 10913b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson if (isThumb && 10923b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson (BBOffsets[WBBId] + BBSizes[WBBId])%4 != 0) { 10933b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson // This is valid Water, but would introduce padding. Remember 10943b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson // it in case we don't find any Water that doesn't do this. 109532c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson if (!FoundWaterThatWouldPad) { 109632c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson FoundWaterThatWouldPad = true; 10973b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson IPThatWouldPad = IP; 1098f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 10993b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson } else { 1100b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterIter = IP; 11013b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson return true; 1102d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng } 110388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 11043b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson if (IP == B) 11053b7573517ccd0f8f9e4bc64cf1923bae68e40d3fBob Wilson break; 110688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 110732c50e8f9920bb7835eb42926945c9a1e6385de5Bob Wilson if (FoundWaterThatWouldPad) { 1108b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterIter = IPThatWouldPad; 11098593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 11108593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 1111b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen return false; 1112b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen} 111388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 11148494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson/// CreateNewWater - No existing WaterList entry will work for 1115b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// CPUsers[CPUserIndex], so create a place to put the CPE. The end of the 1116b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// block is used if in range, and the conditional branch munged so control 1117b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// flow is correct. Otherwise the block is split to create a hole with an 1118757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson/// unconditional branch around it. In either case NewMBB is set to a 1119b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// block following which the new island can be inserted (the WaterList 1120b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// is not adjusted). 11218494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilsonvoid ARMConstantIslands::CreateNewWater(unsigned CPUserIndex, 1122757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson unsigned UserOffset, 1123757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson MachineBasicBlock *&NewMBB) { 1124b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUser &U = CPUsers[CPUserIndex]; 1125b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *UserMI = U.MI; 1126b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *CPEMI = U.CPEMI; 1127b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineBasicBlock *UserMBB = UserMI->getParent(); 11288494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson unsigned OffsetOfNextBlock = BBOffsets[UserMBB->getNumber()] + 1129b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen BBSizes[UserMBB->getNumber()]; 11308593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen assert(OffsetOfNextBlock== BBOffsets[UserMBB->getNumber()+1]); 1131b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 113236fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // If the block does not end in an unconditional branch already, and if the 113336fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // end of the block is within range, make new water there. (The addition 113436fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // below is for the unconditional branch we will be adding: 4 bytes on ARM + 113536fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson // Thumb2, 2 on Thumb1. Possible Thumb1 alignment padding is allowed for 11368593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // inside OffsetIsInRange. 113736fa5321bacf351f47d6193f56c464e6ab93b934Bob Wilson if (BBHasFallthrough(UserMBB) && 1138d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng OffsetIsInRange(UserOffset, OffsetOfNextBlock + (isThumb1 ? 2: 4), 1139d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng U.MaxDisp, U.NegOk, U.IsSoImm)) { 1140893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Split at end of block\n"); 1141b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (&UserMBB->back() == UserMI) 1142b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen assert(BBHasFallthrough(UserMBB) && "Expected a fallthrough BB!"); 11437896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner NewMBB = llvm::next(MachineFunction::iterator(UserMBB)); 1144b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // Add an unconditional branch from UserMBB to fallthrough block. 1145b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // Record it for branch lengthening; this new branch will not get out of 1146b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // range, but if the preceding conditional branch is out of range, the 1147b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // targets will be exchanged, and the altered branch may be out of 1148b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // range, so the machinery has to know about it. 11495e47a9a6e46bd271eba058fb831da1a1edf8707cDavid Goodwin int UncondBr = isThumb ? ((isThumb2) ? ARM::t2B : ARM::tB) : ARM::B; 1150c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(UserMBB, DebugLoc(), TII->get(UncondBr)).addMBB(NewMBB); 1151b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned MaxDisp = getUnconditionalBrDisp(UncondBr); 11528494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson ImmBranches.push_back(ImmBranch(&UserMBB->back(), 1153b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MaxDisp, false, UncondBr)); 1154d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng int delta = isThumb1 ? 2 : 4; 1155b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen BBSizes[UserMBB->getNumber()] += delta; 1156b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen AdjustBBOffsetsAfter(UserMBB, delta); 1157b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen } else { 1158b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // What a big block. Find a place within the block to split it. 1159d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // This is a little tricky on Thumb1 since instructions are 2 bytes 1160b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // and constant pool entries are 4 bytes: if instruction I references 1161b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // island CPE, and instruction I+1 references CPE', it will 1162b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // not work well to put CPE as far forward as possible, since then 1163b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // CPE' cannot immediately follow it (that location is 2 bytes 1164b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // farther away from I+1 than CPE was from I) and we'd need to create 11658593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // a new island. So, we make a first guess, then walk through the 11668593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // instructions between the one currently being looked at and the 11678593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // possible insertion point, and make sure any other instructions 11688593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // that reference CPEs will be able to use the same island area; 11698593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // if not, we back up the insertion point. 11708593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen 1171b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // The 4 in the following is for the unconditional branch we'll be 1172d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // inserting (allows for long branch on Thumb1). Alignment of the 11738593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // island is handled inside OffsetIsInRange. 11748593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen unsigned BaseInsertOffset = UserOffset + U.MaxDisp -4; 1175b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // This could point off the end of the block if we've already got 1176b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // constant pool entries following this block; only the last one is 1177b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // in the water list. Back past any possible branches (allow for a 1178b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // conditional and a maximally long unconditional). 1179b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (BaseInsertOffset >= BBOffsets[UserMBB->getNumber()+1]) 11808494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson BaseInsertOffset = BBOffsets[UserMBB->getNumber()+1] - 1181d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng (isThumb1 ? 6 : 8); 1182b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned EndInsertOffset = BaseInsertOffset + 1183b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPEMI->getOperand(2).getImm(); 1184b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineBasicBlock::iterator MI = UserMI; 1185b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen ++MI; 1186b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned CPUIndex = CPUserIndex+1; 1187719510a178a910feb1db707140011c32a30992c4Evan Cheng unsigned NumCPUsers = CPUsers.size(); 1188719510a178a910feb1db707140011c32a30992c4Evan Cheng MachineInstr *LastIT = 0; 118952e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray for (unsigned Offset = UserOffset+TII->GetInstSizeInBytes(UserMI); 1190b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen Offset < BaseInsertOffset; 119152e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray Offset += TII->GetInstSizeInBytes(MI), 1192719510a178a910feb1db707140011c32a30992c4Evan Cheng MI = llvm::next(MI)) { 1193719510a178a910feb1db707140011c32a30992c4Evan Cheng if (CPUIndex < NumCPUsers && CPUsers[CPUIndex].MI == MI) { 1194d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng CPUser &U = CPUsers[CPUIndex]; 11958494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson if (!OffsetIsInRange(Offset, EndInsertOffset, 1196d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng U.MaxDisp, U.NegOk, U.IsSoImm)) { 1197d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng BaseInsertOffset -= (isThumb1 ? 2 : 4); 1198d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng EndInsertOffset -= (isThumb1 ? 2 : 4); 1199f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 1200b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // This is overly conservative, as we don't account for CPEMIs 1201b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // being reused within the block, but it doesn't matter much. 1202b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen EndInsertOffset += CPUsers[CPUIndex].CPEMI->getOperand(2).getImm(); 1203b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUIndex++; 1204f1b214d3ca12f2d85f0d092b4920172bcc797bacDale Johannesen } 1205719510a178a910feb1db707140011c32a30992c4Evan Cheng 1206719510a178a910feb1db707140011c32a30992c4Evan Cheng // Remember the last IT instruction. 1207719510a178a910feb1db707140011c32a30992c4Evan Cheng if (MI->getOpcode() == ARM::t2IT) 1208719510a178a910feb1db707140011c32a30992c4Evan Cheng LastIT = MI; 120988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 1210719510a178a910feb1db707140011c32a30992c4Evan Cheng 1211893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "Split in middle of big block\n"); 1212719510a178a910feb1db707140011c32a30992c4Evan Cheng --MI; 1213719510a178a910feb1db707140011c32a30992c4Evan Cheng 1214719510a178a910feb1db707140011c32a30992c4Evan Cheng // Avoid splitting an IT block. 1215719510a178a910feb1db707140011c32a30992c4Evan Cheng if (LastIT) { 1216719510a178a910feb1db707140011c32a30992c4Evan Cheng unsigned PredReg = 0; 1217719510a178a910feb1db707140011c32a30992c4Evan Cheng ARMCC::CondCodes CC = llvm::getITInstrPredicate(MI, PredReg); 1218719510a178a910feb1db707140011c32a30992c4Evan Cheng if (CC != ARMCC::AL) 1219719510a178a910feb1db707140011c32a30992c4Evan Cheng MI = LastIT; 1220719510a178a910feb1db707140011c32a30992c4Evan Cheng } 1221719510a178a910feb1db707140011c32a30992c4Evan Cheng NewMBB = SplitBlockBeforeInstr(MI); 1222b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen } 1223b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen} 1224b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1225b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// HandleConstantPoolUser - Analyze the specified user, checking to see if it 122639bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson/// is out-of-range. If so, pick up the constant pool value and move it some 1227b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// place in-range. Return true if we changed any addresses (thus must run 1228b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen/// another pass of branch lengthening), false otherwise. 12295657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::HandleConstantPoolUser(MachineFunction &MF, 12308494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson unsigned CPUserIndex) { 1231b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen CPUser &U = CPUsers[CPUserIndex]; 1232b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *UserMI = U.MI; 1233b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen MachineInstr *CPEMI = U.CPEMI; 12348aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner unsigned CPI = CPEMI->getOperand(1).getIndex(); 1235b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned Size = CPEMI->getOperand(2).getImm(); 12368593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Compute this only once, it's expensive. The 4 or 8 is the value the 1237a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // hardware keeps in the PC. 1238b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned UserOffset = GetOffsetOf(UserMI) + (isThumb ? 4 : 8); 1239768c9f725bda048b3406b6289beb586ff6e933dfEvan Cheng 1240b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // See if the current entry is within range, or there is a clone of it 1241b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // in range. 1242b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen int result = LookForExistingCPEntry(U, UserOffset); 1243b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen if (result==1) return false; 1244b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen else if (result==2) return true; 1245b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1246b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // No existing clone of this CPE is within range. 1247b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // We will be generating a new clone. Get a UID for it. 124839bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson unsigned ID = AFI->createConstPoolEntryUId(); 1249b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen 1250f98032ef64a777fe63d390539f901d7d6d4e868cBob Wilson // Look for water where we can place this CPE. 1251b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *NewIsland = MF.CreateMachineBasicBlock(); 1252b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *NewMBB; 1253b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson water_iterator IP; 1254b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (LookForWater(U, UserOffset, IP)) { 1255b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson DEBUG(errs() << "found water in range\n"); 1256b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *WaterBB = *IP; 1257b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1258b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // If the original WaterList entry was "new water" on this iteration, 1259b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // propagate that to the new island. This is just keeping NewWaterList 1260b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // updated to match the WaterList, which will be updated below. 1261b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (NewWaterList.count(WaterBB)) { 1262b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.erase(WaterBB); 1263b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(NewIsland); 1264b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson } 1265b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // The new CPE goes before the following block (NewMBB). 12667896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner NewMBB = llvm::next(MachineFunction::iterator(WaterBB)); 1267b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1268b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson } else { 1269b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen // No water found. 1270893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << "No water found\n"); 1271757652c5ba820bbea75d8713d7bf3749e4113778Bob Wilson CreateNewWater(CPUserIndex, UserOffset, NewMBB); 1272b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1273b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // SplitBlockBeforeInstr adds to WaterList, which is important when it is 1274b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // called while handling branches so that the water will be seen on the 1275b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // next iteration for constant pools, but in this context, we don't want 1276b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // it. Check for this so it will be removed from the WaterList. 1277b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Also remove any entry from NewWaterList. 1278b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson MachineBasicBlock *WaterBB = prior(MachineFunction::iterator(NewMBB)); 1279b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson IP = std::find(WaterList.begin(), WaterList.end(), WaterBB); 1280b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (IP != WaterList.end()) 1281b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.erase(WaterBB); 1282b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 1283b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // We are adding new water. Update NewWaterList. 1284b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson NewWaterList.insert(NewIsland); 128588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen } 128688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 1287b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // Remove the original WaterList entry; we want subsequent insertions in 1288b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // this vicinity to go after the one we're about to insert. This 1289b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // considerably reduces the number of times we have to move the same CPE 1290b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson // more than once and is also important to ensure the algorithm terminates. 1291b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson if (IP != WaterList.end()) 1292b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson WaterList.erase(IP); 1293b923953733ee6b0f477cd767dcc16f94a0966158Bob Wilson 129488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Okay, we know we can put an island before NewMBB now, do it! 12955657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MF.insert(NewMBB, NewIsland); 129688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 129788e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Update internal data structures to account for the newly inserted MBB. 129888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen UpdateForInsertedWaterBlock(NewIsland); 129988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 130088e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Decrement the old entry, and remove it if refcount becomes 0. 1301ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng DecrementOldEntry(CPI, CPEMI); 130288e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen 130388e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // Now that we have an island to add the CPE to, clone the original CPE and 130488e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen // add it to the island. 1305549dda9d82a5ec0a0cbf429a18d33a8e66062424Bob Wilson U.HighWaterMark = NewIsland; 1306c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner U.CPEMI = BuildMI(NewIsland, DebugLoc(), TII->get(ARM::CONSTPOOL_ENTRY)) 1307a8e2989ece6dc46df59b0768184028257f913843Evan Cheng .addImm(ID).addConstantPoolIndex(CPI).addImm(Size); 130888e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen CPEntries[CPI].push_back(CPEntry(U.CPEMI, ID, 1)); 1309fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCPEs; 1310c99ef085b90b32952b484e8843fb66ad65215b61Evan Cheng 13118593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen BBOffsets[NewIsland->getNumber()] = BBOffsets[NewMBB->getNumber()]; 1312b43216ee4a418257ce5530c02601b77efe86c354Evan Cheng // Compensate for .align 2 in thumb mode. 13134d8e90a026a29a812616690bd77b72e0b5ae6c75Jim Grosbach if (isThumb && (BBOffsets[NewIsland->getNumber()]%4 != 0 || HasInlineAsm)) 13148593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen Size += 2; 1315a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Increase the size of the island block to account for the new entry. 1316a8e2989ece6dc46df59b0768184028257f913843Evan Cheng BBSizes[NewIsland->getNumber()] += Size; 131799c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen AdjustBBOffsetsAfter(NewIsland, Size); 13188494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1319a8e2989ece6dc46df59b0768184028257f913843Evan Cheng // Finally, change the CPI in the instruction operand to be ID. 1320a8e2989ece6dc46df59b0768184028257f913843Evan Cheng for (unsigned i = 0, e = UserMI->getNumOperands(); i != e; ++i) 1321d735b8019b0f297d7c14b55adcd887af24d8e602Dan Gohman if (UserMI->getOperand(i).isCPI()) { 13228aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner UserMI->getOperand(i).setIndex(ID); 1323a8e2989ece6dc46df59b0768184028257f913843Evan Cheng break; 1324a8e2989ece6dc46df59b0768184028257f913843Evan Cheng } 13258494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1326705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Moved CPE to #" << ID << " CPI=" << CPI 1327705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << '\t' << *UserMI); 13288494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1329a8e2989ece6dc46df59b0768184028257f913843Evan Cheng return true; 1330a8e2989ece6dc46df59b0768184028257f913843Evan Cheng} 1331a8e2989ece6dc46df59b0768184028257f913843Evan Cheng 1332ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// RemoveDeadCPEMI - Remove a dead constant pool entry instruction. Update 1333ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// sizes and offsets of impacted basic blocks. 1334ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Chengvoid ARMConstantIslands::RemoveDeadCPEMI(MachineInstr *CPEMI) { 1335ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng MachineBasicBlock *CPEBB = CPEMI->getParent(); 13368593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen unsigned Size = CPEMI->getOperand(2).getImm(); 13378593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen CPEMI->eraseFromParent(); 13388593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen BBSizes[CPEBB->getNumber()] -= Size; 13398593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // All succeeding offsets have the current size value added in, fix this. 1340ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (CPEBB->empty()) { 1341d3d9d66dd211d1267e764c7294876d9a227f04caEvan Cheng // In thumb1 mode, the size of island may be padded by two to compensate for 13428593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // the alignment requirement. Then it will now be 2 when the block is 1343ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng // empty, so fix this. 1344ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng // All succeeding offsets have the current size value added in, fix this. 1345ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (BBSizes[CPEBB->getNumber()] != 0) { 13468593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen Size += BBSizes[CPEBB->getNumber()]; 1347ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng BBSizes[CPEBB->getNumber()] = 0; 1348ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 1349ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 13508593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen AdjustBBOffsetsAfter(CPEBB, -Size); 13518593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // An island has only one predecessor BB and one successor BB. Check if 13528593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // this BB's predecessor jumps directly to this BB's successor. This 13538593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // shouldn't happen currently. 13548593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen assert(!BBIsJumpedOver(CPEBB) && "How did this happen?"); 13558593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // FIXME: remove the empty blocks after all the work is done? 1356ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng} 1357ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 1358ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// RemoveUnusedCPEntries - Remove constant pool entries whose refcounts 1359ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng/// are zero. 1360ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Chengbool ARMConstantIslands::RemoveUnusedCPEntries() { 1361ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng unsigned MadeChange = false; 1362ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng for (unsigned i = 0, e = CPEntries.size(); i != e; ++i) { 1363ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng std::vector<CPEntry> &CPEs = CPEntries[i]; 1364ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng for (unsigned j = 0, ee = CPEs.size(); j != ee; ++j) { 1365ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng if (CPEs[j].RefCount == 0 && CPEs[j].CPEMI) { 1366ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng RemoveDeadCPEMI(CPEs[j].CPEMI); 1367ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng CPEs[j].CPEMI = NULL; 1368ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng MadeChange = true; 1369ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 1370ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng } 13718494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson } 1372ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng return MadeChange; 1373ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng} 1374ed884f3a2f7225a0ea40fc18964b6f949cac3680Evan Cheng 137588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// BBIsInRange - Returns true if the distance between specific MI and 137643aeab68a69e443c528092b4424a498d813f96b7Evan Cheng/// specific BB can fit in MI's displacement field. 1377c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Chengbool ARMConstantIslands::BBIsInRange(MachineInstr *MI,MachineBasicBlock *DestBB, 1378c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng unsigned MaxDisp) { 1379b71aa2b6ca801d407c702483c412a290ab4af3b2Dale Johannesen unsigned PCAdj = isThumb ? 4 : 8; 1380c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng unsigned BrOffset = GetOffsetOf(MI) + PCAdj; 138199c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen unsigned DestOffset = BBOffsets[DestBB->getNumber()]; 138243aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1383705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << "Branch of destination BB#" << DestBB->getNumber() 1384705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " from BB#" << MI->getParent()->getNumber() 1385705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " max delta=" << MaxDisp 1386705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " from " << GetOffsetOf(MI) << " to " << DestOffset 1387705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << " offset " << int(DestOffset-BrOffset) << "\t" << *MI); 1388c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng 13898593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (BrOffset <= DestOffset) { 13908593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // Branch before the Dest. 13918593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (DestOffset-BrOffset <= MaxDisp) 13928593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 13938593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } else { 13948593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen if (BrOffset-DestOffset <= MaxDisp) 13958593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return true; 13968593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen } 13978593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen return false; 139843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng} 139943aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1400d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// FixUpImmediateBr - Fix up an immediate branch whose destination is too far 1401d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// away to fit in its displacement field. 14025657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::FixUpImmediateBr(MachineFunction &MF, ImmBranch &Br) { 1403d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = Br.MI; 14048aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *DestBB = MI->getOperand(0).getMBB(); 1405d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1406c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng // Check to see if the DestBB is already in-range. 1407c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng if (BBIsInRange(MI, DestBB, Br.MaxDisp)) 1408d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return false; 1409d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1410d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng if (!Br.isCond) 14115657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return FixUpUnconditionalBr(MF, Br); 14125657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return FixUpConditionalBr(MF, Br); 1413d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 1414d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 141588e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// FixUpUnconditionalBr - Fix up an unconditional branch whose destination is 141688e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// too far away to fit in its displacement field. If the LR register has been 1417d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// spilled in the epilogue, then we can use BL to implement a far jump. 141839bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson/// Otherwise, add an intermediate branch instruction to a branch. 1419d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Chengbool 14205657c01949dca6c012ac60d242d1a8d2ffdf5603Evan ChengARMConstantIslands::FixUpUnconditionalBr(MachineFunction &MF, ImmBranch &Br) { 1421d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = Br.MI; 1422d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineBasicBlock *MBB = MI->getParent(); 142353c67c0218d8420234dd71bf2d9df3388909af77Evan Cheng if (!isThumb1) 142453c67c0218d8420234dd71bf2d9df3388909af77Evan Cheng llvm_unreachable("FixUpUnconditionalBr is Thumb1 only!"); 1425d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1426d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // Use BL to implement far jump. 1427d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng Br.MaxDisp = (1 << 21) * 2; 14285080f4d9919d39b367891dc51e739c571a66036cChris Lattner MI->setDesc(TII->get(ARM::tBfar)); 1429d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng BBSizes[MBB->getNumber()] += 2; 143099c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen AdjustBBOffsetsAfter(MBB, 2); 1431d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng HasFarJump = true; 1432fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumUBrFixed; 1433bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng 1434705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Changed B to long jump " << *MI); 1435bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng 1436d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return true; 1437d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 1438d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 143988e37ae36652546c8e409cab69a1777af63cf095Dale Johannesen/// FixUpConditionalBr - Fix up a conditional branch whose destination is too 1440d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// far away to fit in its displacement field. It is converted to an inverse 1441d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// conditional branch + an unconditional branch to the destination. 1442af5cbcb809bdbd30ebacab942994721c134d16a2Evan Chengbool 14435657c01949dca6c012ac60d242d1a8d2ffdf5603Evan ChengARMConstantIslands::FixUpConditionalBr(MachineFunction &MF, ImmBranch &Br) { 1444af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MachineInstr *MI = Br.MI; 14458aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *DestBB = MI->getOperand(0).getMBB(); 1446af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 144739bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // Add an unconditional branch to the destination and invert the branch 1448d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng // condition to jump over it: 1449af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // blt L1 1450af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // => 1451af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // bge L2 1452af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // b L1 1453af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // L2: 14549a1ceaedc282f0cae31f2723f4d6c00c7b88fe90Chris Lattner ARMCC::CondCodes CC = (ARMCC::CondCodes)MI->getOperand(1).getImm(); 1455af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng CC = ARMCC::getOppositeCondition(CC); 14560e1d37904abbf7e8c4c478408253dd995f3040f4Evan Cheng unsigned CCReg = MI->getOperand(2).getReg(); 1457af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 1458af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // If the branch is at the end of its MBB and that has a fall-through block, 1459af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // direct the updated conditional branch to the fall-through block. Otherwise, 1460af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // split the MBB before the next instruction. 1461af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 1462bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng MachineInstr *BMI = &MBB->back(); 1463bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng bool NeedSplit = (BMI != MI) || !BBHasFallthrough(MBB); 146443aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 1465fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumCBrFixed; 1466bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng if (BMI != MI) { 14677896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner if (llvm::next(MachineBasicBlock::iterator(MI)) == prior(MBB->end()) && 1468bd5d3dbdbe46c7325545a7cb8c891c0347375451Evan Cheng BMI->getOpcode() == Br.UncondBr) { 146939bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // Last MI in the BB is an unconditional branch. Can we simply invert the 147043aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // condition and swap destinations: 147143aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // beq L1 147243aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // b L2 147343aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // => 147443aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // bne L2 147543aeab68a69e443c528092b4424a498d813f96b7Evan Cheng // b L1 14768aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MachineBasicBlock *NewDest = BMI->getOperand(0).getMBB(); 1477c0dbec7e1038ee60b8525eb1e8e3eaa6a839bd5bEvan Cheng if (BBIsInRange(MI, NewDest, Br.MaxDisp)) { 1478705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner DEBUG(errs() << " Invert Bcc condition and swap its destination with " 1479705e07f578e2b3af47ddab610feb4e7f2d3063a5Chris Lattner << *BMI); 14808aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner BMI->getOperand(0).setMBB(DestBB); 14818aa797aa51cd4ea1ec6f46f4891a6897944b75b2Chris Lattner MI->getOperand(0).setMBB(NewDest); 148243aeab68a69e443c528092b4424a498d813f96b7Evan Cheng MI->getOperand(1).setImm(CC); 148343aeab68a69e443c528092b4424a498d813f96b7Evan Cheng return true; 148443aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 148543aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 148643aeab68a69e443c528092b4424a498d813f96b7Evan Cheng } 148743aeab68a69e443c528092b4424a498d813f96b7Evan Cheng 148843aeab68a69e443c528092b4424a498d813f96b7Evan Cheng if (NeedSplit) { 1489af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng SplitBlockBeforeInstr(MI); 149039bf051ec2865cd715c41473d2a9fc34ff252534Bob Wilson // No need for the branch to the next block. We're adding an unconditional 1491dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng // branch to the destination. 149252e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray int delta = TII->GetInstSizeInBytes(&MBB->back()); 149356c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen BBSizes[MBB->getNumber()] -= delta; 14947896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineBasicBlock* SplitBB = llvm::next(MachineFunction::iterator(MBB)); 14958593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen AdjustBBOffsetsAfter(SplitBB, -delta); 1496dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng MBB->back().eraseFromParent(); 14978593e418555fdae21a070357fd8734b4069c17d0Dale Johannesen // BBOffsets[SplitBB] is wrong temporarily, fixed below 1498dd353b8ad747a8731a191848ff5db978a70bd0fbEvan Cheng } 14997896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner MachineBasicBlock *NextBB = llvm::next(MachineFunction::iterator(MBB)); 15008494526a2396fd9cde027ab6ae11dd28b54ac90eBob Wilson 1501893e1c90a03a53cf13f73849324e83612688428aChris Lattner DEBUG(errs() << " Insert B to BB#" << DestBB->getNumber() 1502893e1c90a03a53cf13f73849324e83612688428aChris Lattner << " also invert condition and change dest. to BB#" 1503893e1c90a03a53cf13f73849324e83612688428aChris Lattner << NextBB->getNumber() << "\n"); 1504af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 150556c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen // Insert a new conditional branch and a new unconditional branch. 1506af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng // Also update the ImmBranch as well as adding a new entry for the new branch. 1507c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(MBB, DebugLoc(), TII->get(MI->getOpcode())) 1508b67284057ee130114055309eabe0bcd1af13777dDale Johannesen .addMBB(NextBB).addImm(CC).addReg(CCReg); 1509af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng Br.MI = &MBB->back(); 151052e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray BBSizes[MBB->getNumber()] += TII->GetInstSizeInBytes(&MBB->back()); 1511c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(MBB, DebugLoc(), TII->get(Br.UncondBr)).addMBB(DestBB); 151252e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray BBSizes[MBB->getNumber()] += TII->GetInstSizeInBytes(&MBB->back()); 1513a9b8b8d62c67e96bc4dc2ed25298c539102f8638Evan Cheng unsigned MaxDisp = getUnconditionalBrDisp(Br.UncondBr); 1514a0bf794eb60b6795a121efcb9ff759e9e0955772Evan Cheng ImmBranches.push_back(ImmBranch(&MBB->back(), MaxDisp, false, Br.UncondBr)); 151556c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen 151656c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen // Remove the old conditional branch. It may or may not still be in MBB. 151752e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray BBSizes[MI->getParent()->getNumber()] -= TII->GetInstSizeInBytes(MI); 1518af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng MI->eraseFromParent(); 1519af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng 152056c42ef3e43f8eb75c435e781d0ac8251c7588a1Dale Johannesen // The net size change is an addition of one unconditional branch. 152152e724ad7e679ee590f4bd763d55280586a8f1bcNicolas Geoffray int delta = TII->GetInstSizeInBytes(&MBB->back()); 152299c49a4b94ffabdd22f55e8274c7f92892e25559Dale Johannesen AdjustBBOffsetsAfter(MBB, delta); 1523af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng return true; 1524af5cbcb809bdbd30ebacab942994721c134d16a2Evan Cheng} 1525d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng 1526d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng/// UndoLRSpillRestore - Remove Thumb push / pop instructions that only spills 15274b322e58b77d16f103d88a3af3a4ebd2675245a0Evan Cheng/// LR / restores LR to pc. FIXME: This is done here because it's only possible 15284b322e58b77d16f103d88a3af3a4ebd2675245a0Evan Cheng/// to do this if tBfar is not used. 1529d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Chengbool ARMConstantIslands::UndoLRSpillRestore() { 1530d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng bool MadeChange = false; 1531d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng for (unsigned i = 0, e = PushPopMIs.size(); i != e; ++i) { 1532d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng MachineInstr *MI = PushPopMIs[i]; 1533815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson // First two operands are predicates. 153444bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng if (MI->getOpcode() == ARM::tPOP_RET && 1535815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson MI->getOperand(2).getReg() == ARM::PC && 1536815baebe1c8dc02accf128ae10dff9a1742d3244Bob Wilson MI->getNumExplicitOperands() == 3) { 1537b67284057ee130114055309eabe0bcd1af13777dDale Johannesen BuildMI(MI->getParent(), MI->getDebugLoc(), TII->get(ARM::tBX_RET)); 153844bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng MI->eraseFromParent(); 153944bec52b1b7e9a3ac1efbae90db240b8c1ca2ad4Evan Cheng MadeChange = true; 1540d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng } 1541d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng } 1542d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng return MadeChange; 1543d1b2c1e88fe4a7728ca9739b0f1c6fd90a19c5fdEvan Cheng} 15445657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 1545a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Chengbool ARMConstantIslands::OptimizeThumb2Instructions(MachineFunction &MF) { 1546a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng bool MadeChange = false; 1547a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1548a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // Shrink ADR and LDR from constantpool. 1549a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng for (unsigned i = 0, e = CPUsers.size(); i != e; ++i) { 1550a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng CPUser &U = CPUsers[i]; 1551a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Opcode = U.MI->getOpcode(); 1552a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned NewOpc = 0; 1553a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Scale = 1; 1554a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned Bits = 0; 1555a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng switch (Opcode) { 1556a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng default: break; 15576b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson case ARM::t2LEApcrel: 1558a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (isARMLowRegister(U.MI->getOperand(0).getReg())) { 1559a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng NewOpc = ARM::tLEApcrel; 1560a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Bits = 8; 1561a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Scale = 4; 1562a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1563a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng break; 1564a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng case ARM::t2LDRpci: 1565a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (isARMLowRegister(U.MI->getOperand(0).getReg())) { 1566a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng NewOpc = ARM::tLDRpci; 1567a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Bits = 8; 1568a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng Scale = 4; 1569a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1570a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng break; 1571a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1572a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1573a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (!NewOpc) 1574a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng continue; 1575a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1576a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned UserOffset = GetOffsetOf(U.MI) + 4; 1577a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng unsigned MaxOffs = ((1 << Bits) - 1) * Scale; 1578a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // FIXME: Check if offset is multiple of scale if scale is not 4. 1579a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if (CPEIsInRange(U.MI, UserOffset, U.CPEMI, MaxOffs, false, true)) { 1580a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng U.MI->setDesc(TII->get(NewOpc)); 1581a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MachineBasicBlock *MBB = U.MI->getParent(); 1582a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng BBSizes[MBB->getNumber()] -= 2; 1583a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng AdjustBBOffsetsAfter(MBB, -2); 1584a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng ++NumT2CPShrunk; 1585a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MadeChange = true; 1586a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1587a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng } 1588a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1589a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng MadeChange |= OptimizeThumb2Branches(MF); 159001dec0e545de18aadcd3911563a93d10a625be80Jim Grosbach MadeChange |= OptimizeThumb2JumpTables(MF); 1591a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng return MadeChange; 1592a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng} 1593a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1594a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Chengbool ARMConstantIslands::OptimizeThumb2Branches(MachineFunction &MF) { 159531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng bool MadeChange = false; 159631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 159731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng for (unsigned i = 0, e = ImmBranches.size(); i != e; ++i) { 159831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng ImmBranch &Br = ImmBranches[i]; 159931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Opcode = Br.MI->getOpcode(); 160031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned NewOpc = 0; 160131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Scale = 1; 160231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng unsigned Bits = 0; 160331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng switch (Opcode) { 160431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng default: break; 160531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng case ARM::t2B: 160631b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng NewOpc = ARM::tB; 160731b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Bits = 11; 160831b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Scale = 2; 160931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng break; 1610de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng case ARM::t2Bcc: { 161131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng NewOpc = ARM::tBcc; 161231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng Bits = 8; 1613de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Scale = 2; 161431b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng break; 161531b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 1616de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1617de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (NewOpc) { 1618de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned MaxOffs = ((1 << (Bits-1))-1) * Scale; 1619de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MachineBasicBlock *DestBB = Br.MI->getOperand(0).getMBB(); 1620de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (BBIsInRange(Br.MI, DestBB, MaxOffs)) { 1621de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Br.MI->setDesc(TII->get(NewOpc)); 1622de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MachineBasicBlock *MBB = Br.MI->getParent(); 1623de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng BBSizes[MBB->getNumber()] -= 2; 1624de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng AdjustBBOffsetsAfter(MBB, -2); 1625de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng ++NumT2BrShrunk; 1626de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MadeChange = true; 1627de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1628de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1629de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng 1630de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Opcode = Br.MI->getOpcode(); 1631de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (Opcode != ARM::tBcc) 163231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng continue; 163331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 1634de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = 0; 1635de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned PredReg = 0; 1636de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng ARMCC::CondCodes Pred = llvm::getInstrPredicate(Br.MI, PredReg); 1637de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (Pred == ARMCC::EQ) 1638de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = ARM::tCBZ; 1639de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng else if (Pred == ARMCC::NE) 1640de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng NewOpc = ARM::tCBNZ; 1641de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (!NewOpc) 1642de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng continue; 164331b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng MachineBasicBlock *DestBB = Br.MI->getOperand(0).getMBB(); 1644de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng // Check if the distance is within 126. Subtract starting offset by 2 1645de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng // because the cmp will be eliminated. 1646de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned BrOffset = GetOffsetOf(Br.MI) + 4 - 2; 1647de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned DestOffset = BBOffsets[DestBB->getNumber()]; 1648de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (BrOffset < DestOffset && (DestOffset - BrOffset) <= 126) { 1649de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MachineBasicBlock::iterator CmpMI = Br.MI; --CmpMI; 165097a884d602538705644e296a57a039959cdb6f6eJim Grosbach if (CmpMI->getOpcode() == ARM::tCMPi8) { 1651de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng unsigned Reg = CmpMI->getOperand(0).getReg(); 1652de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Pred = llvm::getInstrPredicate(CmpMI, PredReg); 1653de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng if (Pred == ARMCC::AL && 1654de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng CmpMI->getOperand(1).getImm() == 0 && 1655de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng isARMLowRegister(Reg)) { 1656de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MachineBasicBlock *MBB = Br.MI->getParent(); 1657de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MachineInstr *NewBR = 1658de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng BuildMI(*MBB, CmpMI, Br.MI->getDebugLoc(), TII->get(NewOpc)) 1659de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng .addReg(Reg).addMBB(DestBB, Br.MI->getOperand(0).getTargetFlags()); 1660de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng CmpMI->eraseFromParent(); 1661de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Br.MI->eraseFromParent(); 1662de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng Br.MI = NewBR; 1663de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng BBSizes[MBB->getNumber()] -= 2; 1664de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng AdjustBBOffsetsAfter(MBB, -2); 1665de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng ++NumCBZ; 1666de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng MadeChange = true; 1667de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 1668de17fb6e4dd8f169f707d58d4e124c8d4d2c7dbaEvan Cheng } 166931b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 167031b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng } 167131b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng 167231b99dd76035067b1c3cc6c7e9d663b7b0210938Evan Cheng return MadeChange; 1673a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng} 1674a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng 1675a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng/// OptimizeThumb2JumpTables - Use tbb / tbh instructions to generate smaller 1676a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng/// jumptables when it's possible. 16775657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Chengbool ARMConstantIslands::OptimizeThumb2JumpTables(MachineFunction &MF) { 16785657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool MadeChange = false; 16795657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 16805657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng // FIXME: After the tables are shrunk, can we get rid some of the 16815657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng // constantpool tables? 16821fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineJumpTableInfo *MJTI = MF.getJumpTableInfo(); 1683b1e803985d3378538ae9cff7eed4102c002d1e22Chris Lattner if (MJTI == 0) return false; 168426b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach 16855657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 16865657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned i = 0, e = T2JumpTables.size(); i != e; ++i) { 16875657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineInstr *MI = T2JumpTables[i]; 16885657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const TargetInstrDesc &TID = MI->getDesc(); 16895657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned NumOps = TID.getNumOperands(); 16905657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned JTOpIdx = NumOps - (TID.isPredicable() ? 3 : 2); 16915657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineOperand JTOP = MI->getOperand(JTOpIdx); 16925657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned JTI = JTOP.getIndex(); 16935657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng assert(JTI < JT.size()); 16945657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 16951fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach bool ByteOk = true; 16961fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach bool HalfWordOk = true; 169780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach unsigned JTOffset = GetOffsetOf(MI) + 4; 169880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 16995657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned j = 0, ee = JTBBs.size(); j != ee; ++j) { 17005657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *MBB = JTBBs[j]; 17015657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned DstOffset = BBOffsets[MBB->getNumber()]; 17028770f747a98194056805f1b7cbcb0b75a7633b87Evan Cheng // Negative offset is not ok. FIXME: We should change BB layout to make 17038770f747a98194056805f1b7cbcb0b75a7633b87Evan Cheng // sure all the branches are forward. 1704d26b14c34cbcee1448b86b524578fc51cc979023Evan Cheng if (ByteOk && (DstOffset - JTOffset) > ((1<<8)-1)*2) 17055657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng ByteOk = false; 170625f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned TBHLimit = ((1<<16)-1)*2; 170725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng if (HalfWordOk && (DstOffset - JTOffset) > TBHLimit) 17085657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng HalfWordOk = false; 17095657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!ByteOk && !HalfWordOk) 17105657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 17115657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17125657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17135657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (ByteOk || HalfWordOk) { 17145657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock *MBB = MI->getParent(); 17155657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned BaseReg = MI->getOperand(0).getReg(); 17165657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool BaseRegKill = MI->getOperand(0).isKill(); 17175657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!BaseRegKill) 17185657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17195657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng unsigned IdxReg = MI->getOperand(1).getReg(); 17205657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool IdxRegKill = MI->getOperand(1).isKill(); 1721c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 1722c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // Scan backwards to find the instruction that defines the base 1723c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // register. Due to post-RA scheduling, we can't count on it 1724c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // immediately preceding the branch instruction. 17255657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng MachineBasicBlock::iterator PrevI = MI; 1726c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineBasicBlock::iterator B = MBB->begin(); 1727c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach while (PrevI != B && !PrevI->definesRegister(BaseReg)) 1728c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach --PrevI; 1729c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 1730c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // If for some reason we didn't find it, we can't do anything, so 1731c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // just skip this one. 1732c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach if (!PrevI->definesRegister(BaseReg)) 17335657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17345657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 1735c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineInstr *AddrMI = PrevI; 17365657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng bool OptOk = true; 173726b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach // Examine the instruction that calculates the jumptable entry address. 1738c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // Make sure it only defines the base register and kills any uses 1739c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // other than the index register. 17405657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng for (unsigned k = 0, eee = AddrMI->getNumOperands(); k != eee; ++k) { 17415657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng const MachineOperand &MO = AddrMI->getOperand(k); 17425657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!MO.isReg() || !MO.getReg()) 17435657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17445657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (MO.isDef() && MO.getReg() != BaseReg) { 17455657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng OptOk = false; 17465657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 17475657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17485657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (MO.isUse() && !MO.isKill() && MO.getReg() != IdxReg) { 17495657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng OptOk = false; 17505657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng break; 17515657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17525657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17535657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng if (!OptOk) 17545657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng continue; 17555657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17566b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson // Now scan back again to find the tLEApcrel or t2LEApcrelJT instruction 1757c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach // that gave us the initial base register definition. 1758c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach for (--PrevI; PrevI != B && !PrevI->definesRegister(BaseReg); --PrevI) 1759c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach ; 1760c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach 17616b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson // The instruction should be a tLEApcrel or t2LEApcrelJT; we want 1762a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng // to delete it as well. 1763c7937ae025194cb62ffcd592785c3ad97e7882ceJim Grosbach MachineInstr *LeaMI = PrevI; 1764a1efbbdbf3217598f334a6f39dab84ca06f5de41Evan Cheng if ((LeaMI->getOpcode() != ARM::tLEApcrelJT && 17656b8719fd7dc527e4c1910ae49ebee61d90907c08Owen Anderson LeaMI->getOpcode() != ARM::t2LEApcrelJT) || 17665657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng LeaMI->getOperand(0).getReg() != BaseReg) 176725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OptOk = false; 176825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 176925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng if (!OptOk) 177025f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng continue; 177125f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 1772d092a87ba3f905a6801a0bdf816267329cf0391cJim Grosbach unsigned Opc = ByteOk ? ARM::t2TBB_JT : ARM::t2TBH_JT; 177325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MachineInstr *NewJTMI = BuildMI(MBB, MI->getDebugLoc(), TII->get(Opc)) 177425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addReg(IdxReg, getKillRegState(IdxRegKill)) 177525f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addJumpTableIndex(JTI, JTOP.getTargetFlags()) 177625f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng .addImm(MI->getOperand(JTOpIdx+1).getImm()); 177725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng // FIXME: Insert an "ALIGN" instruction to ensure the next instruction 177825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng // is 2-byte aligned. For now, asm printer will fix it up. 177925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned NewSize = TII->GetInstSizeInBytes(NewJTMI); 178025f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng unsigned OrigSize = TII->GetInstSizeInBytes(AddrMI); 178125f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OrigSize += TII->GetInstSizeInBytes(LeaMI); 178225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng OrigSize += TII->GetInstSizeInBytes(MI); 178325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 178425f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng AddrMI->eraseFromParent(); 178525f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng LeaMI->eraseFromParent(); 178625f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MI->eraseFromParent(); 178725f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 178825f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng int delta = OrigSize - NewSize; 178925f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng BBSizes[MBB->getNumber()] -= delta; 179025f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng AdjustBBOffsetsAfter(MBB, -delta); 179125f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng 179225f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng ++NumTBs; 179325f7cfc3cccba6f569f29f79ea533bae960b93c0Evan Cheng MadeChange = true; 17945657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17955657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng } 17965657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng 17975657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng return MadeChange; 17985657c01949dca6c012ac60d242d1a8d2ffdf5603Evan Cheng} 17991fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 18009249efe4c7451e83fb4c904fd7fcc8edfe08d815Jim Grosbach/// ReorderThumb2JumpTables - Adjust the function's block layout to ensure that 18019249efe4c7451e83fb4c904fd7fcc8edfe08d815Jim Grosbach/// jump tables always branch forwards, since that's what tbb and tbh need. 180280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbachbool ARMConstantIslands::ReorderThumb2JumpTables(MachineFunction &MF) { 180380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach bool MadeChange = false; 180480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 180580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineJumpTableInfo *MJTI = MF.getJumpTableInfo(); 1806b1e803985d3378538ae9cff7eed4102c002d1e22Chris Lattner if (MJTI == 0) return false; 180726b8ef53ff2ff1ffd72d140b5be264e32dee0195Jim Grosbach 180880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 180980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (unsigned i = 0, e = T2JumpTables.size(); i != e; ++i) { 181080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineInstr *MI = T2JumpTables[i]; 181180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const TargetInstrDesc &TID = MI->getDesc(); 181280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach unsigned NumOps = TID.getNumOperands(); 181380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach unsigned JTOpIdx = NumOps - (TID.isPredicable() ? 3 : 2); 181480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineOperand JTOP = MI->getOperand(JTOpIdx); 181580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach unsigned JTI = JTOP.getIndex(); 181680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach assert(JTI < JT.size()); 181780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 181880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // We prefer if target blocks for the jump table come after the jump 181980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // instruction so we can use TB[BH]. Loop through the target blocks 182080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // and try to adjust them such that that's true. 182108cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach int JTNumber = MI->getParent()->getNumber(); 182280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 182380697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach for (unsigned j = 0, ee = JTBBs.size(); j != ee; ++j) { 182480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *MBB = JTBBs[j]; 182508cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach int DTNumber = MBB->getNumber(); 182680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 182708cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach if (DTNumber < JTNumber) { 182880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // The destination precedes the switch. Try to move the block forward 182980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // so we have a positive offset. 183080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *NewBB = 183180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach AdjustJTTargetBlockForward(MBB, MI->getParent()); 183280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach if (NewBB) 183300a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach MJTI->ReplaceMBBInJumpTable(JTI, JTBBs[j], NewBB); 183480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MadeChange = true; 183580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 183680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 183780697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 183880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 183980697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach return MadeChange; 184080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach} 184180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach 18421fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim GrosbachMachineBasicBlock *ARMConstantIslands:: 18431fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim GrosbachAdjustJTTargetBlockForward(MachineBasicBlock *BB, MachineBasicBlock *JTBB) 18441fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach{ 18451fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineFunction &MF = *BB->getParent(); 18461fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 184703e2d44722c1ebd3953007db0579147b46efba18Jim Grosbach // If the destination block is terminated by an unconditional branch, 184880697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach // try to move it; otherwise, create a new block following the jump 184908cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // table that branches back to the actual target. This is a very simple 185008cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // heuristic. FIXME: We can definitely improve it. 185180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach MachineBasicBlock *TBB = 0, *FBB = 0; 185280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach SmallVector<MachineOperand, 4> Cond; 1853a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach SmallVector<MachineOperand, 4> CondPrior; 1854a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MachineFunction::iterator BBi = BB; 1855a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MachineFunction::iterator OldPrior = prior(BBi); 185600a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach 1857ca215e7804ca5d85e19e31850c3ba3d155624e89Jim Grosbach // If the block terminator isn't analyzable, don't try to move the block 1858a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach bool B = TII->AnalyzeBranch(*BB, TBB, FBB, Cond); 1859ca215e7804ca5d85e19e31850c3ba3d155624e89Jim Grosbach 1860a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach // If the block ends in an unconditional branch, move it. The prior block 1861a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach // has to have an analyzable terminator for us to move this one. Be paranoid 186208cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // and make sure we're not trying to move the entry block of the function. 1863a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach if (!B && Cond.empty() && BB != MF.begin() && 1864a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach !TII->AnalyzeBranch(*OldPrior, TBB, FBB, CondPrior)) { 186580697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach BB->moveAfter(JTBB); 186680697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach OldPrior->updateTerminator(); 186700a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach BB->updateTerminator(); 186808cbda56b6a45a2c29bdf3d9668ad614ad86cb77Jim Grosbach // Update numbering to account for the block being moved. 1869a0a95a3c1cea79757854cf39ba07734b39e2b0e9Jim Grosbach MF.RenumberBlocks(); 187080697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach ++NumJTMoved; 187180697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach return NULL; 187280697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach } 18731fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 18741fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Create a new MBB for the code after the jump BB. 18751fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineBasicBlock *NewBB = 18761fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MF.CreateMachineBasicBlock(JTBB->getBasicBlock()); 18771fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MachineFunction::iterator MBBI = JTBB; ++MBBI; 18781fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach MF.insert(MBBI, NewBB); 18791fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 18801fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Add an unconditional branch from NewBB to BB. 18811fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // There doesn't seem to be meaningful DebugInfo available; this doesn't 18821fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // correspond directly to anything in the source. 18831fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach assert (isThumb2 && "Adjusting for TB[BH] but not in Thumb2?"); 1884c7f3ace20c325521c68335a1689645b43b06ddf0Chris Lattner BuildMI(NewBB, DebugLoc(), TII->get(ARM::t2B)).addMBB(BB); 18851fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 188600a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach // Update internal data structures to account for the newly inserted MBB. 188700a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach MF.RenumberBlocks(NewBB); 188800a6a1f0225b01229134ecee7a853be638703c36Jim Grosbach 18891fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach // Update the CFG. 18901fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach NewBB->addSuccessor(BB); 18911fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach JTBB->removeSuccessor(BB); 18921fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach JTBB->addSuccessor(NewBB); 18931fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach 189480697d1b266cd3cd3b92edd424d66d573db6b4b1Jim Grosbach ++NumJTInserted; 18951fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach return NewBB; 18961fc7d715aa35703fcc4a87ece718a8c447e8ee72Jim Grosbach} 1897