From e08ec140e0734c9eec86097106995715d672692f Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Tue, 29 Jan 2008 19:01:37 +0000 Subject: [PATCH] Don't let globalopt hack on volatile loads or stores. llvm-svn: 46523 --- lib/Transforms/IPO/GlobalOpt.cpp | 5 ++++- test/Transforms/GlobalOpt/2008-01-29-VolatileGlobal.ll | 9 +++++++++ 2 files changed, 13 insertions(+), 1 deletion(-) create mode 100644 test/Transforms/GlobalOpt/2008-01-29-VolatileGlobal.ll diff --git a/lib/Transforms/IPO/GlobalOpt.cpp b/lib/Transforms/IPO/GlobalOpt.cpp index ea8080e35e8..7bed9e22d11 100644 --- a/lib/Transforms/IPO/GlobalOpt.cpp +++ b/lib/Transforms/IPO/GlobalOpt.cpp @@ -163,12 +163,15 @@ static bool AnalyzeGlobal(Value *V, GlobalStatus &GS, else if (GS.AccessingFunction != F) GS.HasMultipleAccessingFunctions = true; } - if (isa(I)) { + if (LoadInst *LI = dyn_cast(I)) { GS.isLoaded = true; + if (LI->isVolatile()) return true; // Don't hack on volatile loads. } else if (StoreInst *SI = dyn_cast(I)) { // Don't allow a store OF the address, only stores TO the address. if (SI->getOperand(0) == V) return true; + if (SI->isVolatile()) return true; // Don't hack on volatile stores. + // If this is a direct store to the global (i.e., the global is a scalar // value, not an aggregate), keep more specific information about // stores. diff --git a/test/Transforms/GlobalOpt/2008-01-29-VolatileGlobal.ll b/test/Transforms/GlobalOpt/2008-01-29-VolatileGlobal.ll new file mode 100644 index 00000000000..0a8dd499c65 --- /dev/null +++ b/test/Transforms/GlobalOpt/2008-01-29-VolatileGlobal.ll @@ -0,0 +1,9 @@ +; RUN: llvm-as < %s | opt -globalopt | llvm-dis | grep {volatile load} +@t0.1441 = internal global double 0x3FD5555555555555, align 8 ; [#uses=1] + +define double @foo() nounwind { +entry: + %tmp1 = volatile load double* @t0.1441, align 8 ; [#uses=2] + %tmp4 = mul double %tmp1, %tmp1 ; [#uses=1] + ret double %tmp4 +}