LLVM: lib/Target/ARM/ARMBranchTargets.cpp Source File (original) (raw)

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26using namespace llvm;

27

28#define DEBUG_TYPE "arm-branch-targets"

29#define ARM_BRANCH_TARGETS_NAME "ARM Branch Targets"

30

31namespace {

33public:

34 static char ID;

36 void getAnalysisUsage(AnalysisUsage &AU) const override;

39

40private:

42};

43}

44

45char ARMBranchTargets::ID = 0;

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48 false, false)

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50void ARMBranchTargets::getAnalysisUsage(AnalysisUsage &AU) const {

51 AU.setPreservesCFG();

53}

54

56 return new ARMBranchTargets();

57}

58

59bool ARMBranchTargets::runOnMachineFunction(MachineFunction &MF) {

60 if (!MF.getInfo()->branchTargetEnforcement())

61 return false;

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63 LLVM_DEBUG(dbgs() << "********** ARM Branch Targets **********\n"

64 << "********** Function: " << MF.getName() << '\n');

65 const ARMInstrInfo &TII =

66 *static_cast<const ARMInstrInfo *>(MF.getSubtarget().getInstrInfo());

67

68 bool MadeChange = false;

69 for (MachineBasicBlock &MBB : MF) {

70 bool IsFirstBB = &MBB == &MF.front();

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82 addBTI(TII, MBB, IsFirstBB);

83 MadeChange = true;

84 }

85 }

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87 return MadeChange;

88}

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96void ARMBranchTargets::addBTI(const ARMInstrInfo &TII, MachineBasicBlock &MBB,

97 bool IsFirstBB) {

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99 unsigned OpCode = ARM::t2BTI;

100 unsigned MIFlags = 0;

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104 return MI.isMetaInstruction();

105 });

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109 if (IsFirstBB) {

112 << "' to replace with PACBTI\n");

113 OpCode = ARM::t2PACBTI;

115 auto NextMBBI = std::next(MBBI);

117 MBBI = NextMBBI;

118 }

119 }

120

122 << (OpCode == ARM::t2BTI ? "BTI" : "PACBTI")

123 << "' instr into BB '" << MBB.getName() << "'\n");

124

127}

const TargetInstrInfo & TII

#define ARM_BRANCH_TARGETS_NAME

Definition ARMBranchTargets.cpp:29

MachineBasicBlock MachineBasicBlock::iterator MBBI

#define INITIALIZE_PASS(passName, arg, name, cfg, analysis)

Represent the analysis usage information of a pass.

FunctionPass class - This class is used to implement most global optimizations.

const MCInstrDesc & get(unsigned Opcode) const

Return the machine instruction descriptor that corresponds to the specified instruction opcode.

bool isEHPad() const

Returns true if the block is a landing pad.

bool isIRBlockAddressTaken() const

Test whether this block is the target of an IR BlockAddress.

LLVM_ABI DebugLoc findDebugLoc(instr_iterator MBBI)

Find the next valid DebugLoc starting at MBBI, skipping any debug instructions.

LLVM_ABI void eraseFromParent()

This method unlinks 'this' from the containing function and deletes it.

instr_iterator instr_end()

bool isMachineBlockAddressTaken() const

Test whether this block is used as something other than the target of a terminator,...

LLVM_ABI StringRef getName() const

Return the name of the corresponding LLVM basic block, or an empty string.

MachineFunctionPass - This class adapts the FunctionPass interface to allow convenient creation of pa...

void getAnalysisUsage(AnalysisUsage &AU) const override

getAnalysisUsage - Subclasses that override getAnalysisUsage must call this.

const TargetSubtargetInfo & getSubtarget() const

getSubtarget - Return the subtarget for which this machine code is being compiled.

StringRef getName() const

getName - Return the name of the corresponding LLVM function.

Ty * getInfo()

getInfo - Keep track of various per-function pieces of information for backends that would like to do...

const MachineInstrBuilder & setMIFlags(unsigned Flags) const

StringRef - Represent a constant reference to a string, i.e.

unsigned ID

LLVM IR allows to use arbitrary numbers as calling convention identifiers.

This is an optimization pass for GlobalISel generic memory operations.

MachineInstrBuilder BuildMI(MachineFunction &MF, const MIMetadata &MIMD, const MCInstrDesc &MCID)

Builder interface. Specify how to create the initial instruction itself.

FunctionPass * createARMBranchTargetsPass()

auto find_if_not(R &&Range, UnaryPredicate P)

LLVM_ABI raw_ostream & dbgs()

dbgs() - This returns a reference to a raw_ostream for debugging messages.