From 25483911049304c069b76f0a3b2f4f6b2216ef51 Mon Sep 17 00:00:00 2001 From: Rafael Espindola Date: Mon, 4 Jul 2011 04:54:22 +0000 Subject: [PATCH] Move early tail duplication earlier. This fixes the issue noted in PR10251 where early tail dup of bbs with indirectbr would cause a bb to be duplicated into a loop preheader and then into its predecessors, creating phi nodes with identical operands just before register allocation. This helps with jsinterp.o size (__TEXT goes from 163568 to 126656) and a bit with performance 1.005x faster on sunspider (jits still enabled). The result on webkit with the jit disabled is more significant: 1.021x faster. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134372 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/LLVMTargetMachine.cpp | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/lib/CodeGen/LLVMTargetMachine.cpp b/lib/CodeGen/LLVMTargetMachine.cpp index b98fbed695b..0255b28a49d 100644 --- a/lib/CodeGen/LLVMTargetMachine.cpp +++ b/lib/CodeGen/LLVMTargetMachine.cpp @@ -388,6 +388,12 @@ bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM, // Expand pseudo-instructions emitted by ISel. PM.add(createExpandISelPseudosPass()); + // Pre-ra tail duplication. + if (OptLevel != CodeGenOpt::None && !DisableEarlyTailDup) { + PM.add(createTailDuplicatePass(true)); + printAndVerify(PM, "After Pre-RegAlloc TailDuplicate"); + } + // Optimize PHIs before DCE: removing dead PHI cycles may make more // instructions dead. if (OptLevel != CodeGenOpt::None) @@ -416,12 +422,6 @@ bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM, printAndVerify(PM, "After codegen peephole optimization pass"); } - // Pre-ra tail duplication. - if (OptLevel != CodeGenOpt::None && !DisableEarlyTailDup) { - PM.add(createTailDuplicatePass(true)); - printAndVerify(PM, "After Pre-RegAlloc TailDuplicate"); - } - // Run pre-ra passes. if (addPreRegAlloc(PM, OptLevel)) printAndVerify(PM, "After PreRegAlloc passes");