From 1857b51ef57697992afe3955f5f90e79612142d8 Mon Sep 17 00:00:00 2001 From: Eli Friedman Date: Mon, 16 Jan 2012 16:42:21 +0000 Subject: Make sure the non-SSE lowering for fences correctly clobbers EFLAGS. PR11768. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148240 91177308-0d34-0410-b5e6-96231b3b80d8 --- test/CodeGen/X86/2012-01-16-mfence-nosse-flags.ll | 34 +++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 test/CodeGen/X86/2012-01-16-mfence-nosse-flags.ll (limited to 'test/CodeGen/X86/2012-01-16-mfence-nosse-flags.ll') diff --git a/test/CodeGen/X86/2012-01-16-mfence-nosse-flags.ll b/test/CodeGen/X86/2012-01-16-mfence-nosse-flags.ll new file mode 100644 index 0000000..a883d79 --- /dev/null +++ b/test/CodeGen/X86/2012-01-16-mfence-nosse-flags.ll @@ -0,0 +1,34 @@ +; RUN: llc < %s -mtriple=i686-linux -mattr=-sse | FileCheck %s +; PR11768 + +@ptr = external global i8* + +define void @baz() nounwind ssp { +entry: + %0 = load i8** @ptr, align 4 + %cmp = icmp eq i8* %0, null + fence seq_cst + br i1 %cmp, label %if.then, label %if.else + +; Make sure the fence comes before the comparison, since it +; clobbers EFLAGS. + +; CHECK: lock +; CHECK-NEXT: orl {{.*}}, (%esp) +; CHECK-NEXT: cmpl $0 + +if.then: ; preds = %entry + tail call void bitcast (void (...)* @foo to void ()*)() nounwind + br label %if.end + +if.else: ; preds = %entry + tail call void bitcast (void (...)* @bar to void ()*)() nounwind + br label %if.end + +if.end: ; preds = %if.else, %if.then + ret void +} + +declare void @foo(...) + +declare void @bar(...) -- cgit v1.1