LLVM: lib/CodeGen/GCEmptyBasicBlocks.cpp Source File (original) (raw)

1

2

3

4

5

6

7

8

9

10

11

12

13

22

23using namespace llvm;

24

25#define DEBUG_TYPE "gc-empty-basic-blocks"

26

27STATISTIC(NumEmptyBlocksRemoved, "Number of empty blocks removed");

28

30public:

31 static char ID;

32

36

38 return "Remove Empty Basic Blocks.";

39 }

40

42};

43

45 if (MF.size() < 2)

46 return false;

48 int NumRemoved = 0;

49

50

51

54 NextMBB;

55 MBB != LastMBB; MBB = NextMBB) {

56 NextMBB = std::next(MBB);

57

58

59

60 if (MBB->isEHPad() || MBB->hasAddressTaken())

61 continue;

62

64 return MI.isPosition() && MI.isImplicitDef() && MI.isKill() &&

65 MI.isDebugInstr();

66 });

67 if (HasAnyRealCode)

68 continue;

69

71 << " in function " << MF.getName() << ":\n"

72 << *MBB << "\n");

74

75 for (auto &Pred : Preds)

76 Pred->ReplaceUsesOfBlockWith(&*MBB, &*NextMBB);

77

78 if (JTI)

80

81 while (MBB->succ_empty())

82 MBB->removeSuccessor(MBB->succ_end() - 1);

83

84 MBB->eraseFromParent();

85 ++NumRemoved;

86 }

87 NumEmptyBlocksRemoved += NumRemoved;

88 return NumRemoved != 0;

89}

90

93 "Removes empty basic blocks and redirects their uses to their "

94 "fallthrough blocks.",

95 false, false)

96

99}

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

This file defines the SmallVector class.

This file defines the 'Statistic' class, which is designed to be an easy way to expose various metric...

#define STATISTIC(VARNAME, DESC)

GCEmptyBasicBlocks()

Definition GCEmptyBasicBlocks.cpp:33

StringRef getPassName() const override

getPassName - Return a nice clean name for a pass.

Definition GCEmptyBasicBlocks.cpp:37

bool runOnMachineFunction(MachineFunction &MF) override

runOnMachineFunction - This method must be overloaded to perform the desired machine code transformat...

Definition GCEmptyBasicBlocks.cpp:44

static char ID

Definition GCEmptyBasicBlocks.cpp:31

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

MachineFunctionPass(char &ID)

StringRef getName() const

getName - Return the name of the corresponding LLVM function.

const MachineBasicBlock & back() const

BasicBlockListType::iterator iterator

const MachineJumpTableInfo * getJumpTableInfo() const

getJumpTableInfo - Return the jump table info object for the current function.

Representation of each machine instruction.

LLVM_ABI bool ReplaceMBBInJumpTables(MachineBasicBlock *Old, MachineBasicBlock *New)

ReplaceMBBInJumpTables - If Old is the target of any jump tables, update the jump tables to branch to...

static LLVM_ABI PassRegistry * getPassRegistry()

getPassRegistry - Access the global registry object, which is automatically initialized at applicatio...

This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.

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

This is an optimization pass for GlobalISel generic memory operations.

LLVM_ABI MachineFunctionPass * createGCEmptyBasicBlocksPass()

createGCEmptyBasicblocksPass - Empty basic blocks (basic blocks without real code) appear as the resu...

bool any_of(R &&range, UnaryPredicate P)

Provide wrappers to std::any_of which take ranges instead of having to pass begin/end explicitly.

LLVM_ABI void initializeGCEmptyBasicBlocksPass(PassRegistry &)

LLVM_ABI raw_ostream & dbgs()

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