diff options
Diffstat (limited to 'lib/CodeGen/BranchFolding.cpp')
| -rw-r--r-- | lib/CodeGen/BranchFolding.cpp | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/lib/CodeGen/BranchFolding.cpp b/lib/CodeGen/BranchFolding.cpp index d8ec340692..7cc4c2db79 100644 --- a/lib/CodeGen/BranchFolding.cpp +++ b/lib/CodeGen/BranchFolding.cpp @@ -35,12 +35,19 @@ using namespace llvm; STATISTIC(NumDeadBlocks, "Number of dead blocks removed"); STATISTIC(NumBranchOpts, "Number of branches optimized"); STATISTIC(NumTailMerge , "Number of block tails merged"); -static cl::opt<bool> EnableTailMerge("enable-tail-merge", cl::Hidden); - +static cl::opt<cl::boolOrDefault> FlagEnableTailMerge("enable-tail-merge", + cl::init(cl::BOU_UNSET), cl::Hidden); namespace { struct BranchFolder : public MachineFunctionPass { static char ID; - BranchFolder() : MachineFunctionPass((intptr_t)&ID) {} + BranchFolder(bool defaultEnableTailMerge) : + MachineFunctionPass((intptr_t)&ID) { + switch (FlagEnableTailMerge) { + case cl::BOU_UNSET: EnableTailMerge = defaultEnableTailMerge; break; + case cl::BOU_TRUE: EnableTailMerge = true; break; + case cl::BOU_FALSE: EnableTailMerge = false; break; + } + } virtual bool runOnMachineFunction(MachineFunction &MF); virtual const char *getPassName() const { return "Control Flow Optimizer"; } @@ -49,6 +56,7 @@ namespace { bool MadeChange; private: // Tail Merging. + bool EnableTailMerge; bool TailMergeBlocks(MachineFunction &MF); bool TryMergeBlocks(MachineBasicBlock* SuccBB, MachineBasicBlock* PredBB); @@ -79,7 +87,8 @@ static bool CorrectExtraCFGEdges(MachineBasicBlock &MBB, bool isCond, MachineFunction::iterator FallThru); -FunctionPass *llvm::createBranchFoldingPass() { return new BranchFolder(); } +FunctionPass *llvm::createBranchFoldingPass(bool DefaultEnableTailMerge) { + return new BranchFolder(DefaultEnableTailMerge); } /// RemoveDeadBlock - Remove the specified dead machine basic block from the /// function, updating the CFG. |