PR10067: Add missing safety check to call return transformation in MemCpyOpt::processStore. If something accesses the dest of the "copy" between the call and the copy, the performCallSlotOptzn transformation is not valid.

llvm-svn: 132485

1 files changed, 36 insertions, 0 deletions

diff --git a/llvm/test/Transforms/MemCpyOpt/2011-06-02-CallSlotOverwritten.ll b/llvm/test/Transforms/MemCpyOpt/2011-06-02-CallSlotOverwritten.ll
new file mode 100644
index 00000000000..132966ef6b9
--- /dev/null
+++ b/llvm/test/Transforms/MemCpyOpt/2011-06-02-CallSlotOverwritten.ll
@@ -0,0 +1,36 @@
+; RUN: opt < %s -basicaa -memcpyopt -S | FileCheck %s
+; PR10067
+; Make sure the call+copy isn't optimized in such a way that
+; %ret ends up with the wrong value.
+
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n8:16:32"
+target triple = "i386-apple-darwin10"
+
+%struct1 = type { i32, i32 }
+%struct2 = type { %struct1, i8* }
+
+declare void @bar(%struct1* nocapture sret %agg.result) nounwind
+
+define i32 @foo() nounwind {
+  %x = alloca %struct1, align 8
+  %y = alloca %struct2, align 8
+  call void @bar(%struct1* sret %x) nounwind
+; CHECK: call void @bar(%struct1* sret %x)
+
+  %gepn1 = getelementptr inbounds %struct2* %y, i32 0, i32 0, i32 0
+  store i32 0, i32* %gepn1, align 8
+  %gepn2 = getelementptr inbounds %struct2* %y, i32 0, i32 0, i32 1
+  store i32 0, i32* %gepn2, align 4
+
+  %bit1 = bitcast %struct1* %x to i64*
+  %bit2 = bitcast %struct2* %y to i64*
+  %load = load i64* %bit1, align 8
+  store i64 %load, i64* %bit2, align 8
+
+; CHECK: %load = load i64* %bit1, align 8
+; CHECK: store i64 %load, i64* %bit2, align 8
+
+  %gep1 = getelementptr %struct2* %y, i32 0, i32 0, i32 0
+  %ret = load i32* %gep1
+  ret i32 %ret
+}