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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106809 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman
2010-06-24 23:41:59 +00:00
parent 8b94297727
commit 0879e22790
1 changed files with 7 additions and 0 deletions
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7
lib/CodeGen/LLVMTargetMachine.cpp
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@ -330,6 +330,13 @@ bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM,
PM.add(createOptimizePHIsPass()); PM.add(createOptimizePHIsPass());
// Delete dead machine instructions regardless of optimization level. // Delete dead machine instructions regardless of optimization level.
//
// At -O0, fast-isel frequently creates dead instructions.
//
// With optimization, dead code should already be eliminated. However
// there is one known exception: lowered code for arguments that are only
// used by tail calls, where the tail calls reuse the incoming stack
// arguments directly (see t11 in test/CodeGen/X86/sibcall.ll).
PM.add(createDeadMachineInstructionElimPass()); PM.add(createDeadMachineInstructionElimPass());
printAndVerify(PM, "After codegen DCE pass", printAndVerify(PM, "After codegen DCE pass",
/* allowDoubleDefs= */ true); /* allowDoubleDefs= */ true);