From a528bc0e8af8e4d70ba03e03319cce7c5775e4ea Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Thu, 1 Jul 2010 03:49:59 +0000 Subject: [PATCH] Fast isel no longer needs DeadMachineInstrElim to clean up after it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107381 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/LLVMTargetMachine.cpp | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/lib/CodeGen/LLVMTargetMachine.cpp b/lib/CodeGen/LLVMTargetMachine.cpp index d437370031d..bf3137e4953 100644 --- a/lib/CodeGen/LLVMTargetMachine.cpp +++ b/lib/CodeGen/LLVMTargetMachine.cpp @@ -329,19 +329,15 @@ bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM, if (OptLevel != CodeGenOpt::None) PM.add(createOptimizePHIsPass()); - // 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()); - printAndVerify(PM, "After codegen DCE pass", - /* allowDoubleDefs= */ true); - if (OptLevel != CodeGenOpt::None) { + // 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()); + printAndVerify(PM, "After codegen DCE pass", + /* allowDoubleDefs= */ true); + PM.add(createOptimizeExtsPass()); if (!DisableMachineLICM) PM.add(createMachineLICMPass()); -- 2.11.0