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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106809 91177308-0d34-0410-b5e6-96231b3b80d8
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@ -330,6 +330,13 @@ bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM,
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PM.add(createOptimizePHIsPass());
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// Delete dead machine instructions regardless of optimization level.
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//
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// At -O0, fast-isel frequently creates dead instructions.
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//
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// With optimization, dead code should already be eliminated. However
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// there is one known exception: lowered code for arguments that are only
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// used by tail calls, where the tail calls reuse the incoming stack
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// arguments directly (see t11 in test/CodeGen/X86/sibcall.ll).
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PM.add(createDeadMachineInstructionElimPass());
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printAndVerify(PM, "After codegen DCE pass",
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/* allowDoubleDefs= */ true);
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