From 97d14fcb6aa54b66e8513fccea0d0470afa4056a Mon Sep 17 00:00:00 2001 From: Dale Johannesen Date: Sat, 18 Apr 2009 00:09:40 +0000 Subject: [PATCH] Inline asm's were still introducing bogus dependencies; my earlier patch to this code only fixed half of it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69408 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp index 5204113b3aa..b20f061e03c 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp @@ -5111,7 +5111,9 @@ void SelectionDAGLowering::visitInlineAsm(CallSite CS) { /// ConstraintOperands - Information about all of the constraints. std::vector ConstraintOperands; - SDValue Chain = getRoot(); + // We won't need to flush pending loads if this asm doesn't touch + // memory and is nonvolatile. + SDValue Chain = IA->hasSideEffects() ? getRoot() : DAG.getRoot(); SDValue Flag; std::set OutputRegs, InputRegs; @@ -5122,6 +5124,10 @@ void SelectionDAGLowering::visitInlineAsm(CallSite CS) { ConstraintInfos = IA->ParseConstraints(); bool hasMemory = hasInlineAsmMemConstraint(ConstraintInfos, TLI); + // Flush pending loads if this touches memory (includes clobbering it). + // It's possible this is overly conservative. + if (hasMemory) + Chain = getRoot(); unsigned ArgNo = 0; // ArgNo - The argument of the CallInst. unsigned ResNo = 0; // ResNo - The result number of the next output. -- 2.34.1