Fix a memcpy lowering bug. Even though the memcpy alignment is smaller than the desir...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51970 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index a9b7381a096c75d32c88211bf5c8c4ed2911c5a3..8d0d344d62b66442ac3d013e3c83eae0caa701a9 100644 (file)
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -2633,8 +2633,9 @@ bool MeetsMaxMemopRequirement(std::vector<MVT::ValueType> &MemOps,
           if (AllowUnalign)
             VT = MVT::iAny;
         } else {
-          // Give the stack frame object a larger alignment.
-          MFI->setObjectAlignment(FI, NewAlign);
+          // Give the stack frame object a larger alignment if needed.
+          if (MFI->getObjectAlignment(FI) < NewAlign)
+            MFI->setObjectAlignment(FI, NewAlign);
           Align = NewAlign;
         }
       }

diff --git a/test/CodeGen/X86/2008-06-04-MemCpyLoweringBug.ll b/test/CodeGen/X86/2008-06-04-MemCpyLoweringBug.ll
new file mode 100644 (file)
index 0000000..d282761
--- /dev/null
+++ b/test/CodeGen/X86/2008-06-04-MemCpyLoweringBug.ll
@@ -0,0 +1,19 @@
+; RUN: llvm-as < %s | llc -mtriple=i386-apple-darwin -mattr=+sse2 -disable-fp-elim | grep subl | grep 24
+
+       %struct.argument_t = type { i8*, %struct.argument_t*, i32, %struct.ipc_type_t*, i32, void (...)*, void (...)*, void (...)*, void (...)*, void (...)*, i8*, i8*, i8*, i8*, i8*, i32, i32, i32, %struct.routine*, %struct.argument_t*, %struct.argument_t*, %struct.argument_t*, %struct.argument_t*, %struct.argument_t*, %struct.argument_t*, %struct.argument_t*, i32, i32, i32, i32, i32, i32 }
+       %struct.ipc_type_t = type { i8*, %struct.ipc_type_t*, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i8*, i8*, i32, i32, i32, i32, i32, i32, %struct.ipc_type_t*, i8*, i8*, i8*, i8*, i8*, i8*, i8*, i8* }
+       %struct.routine = type opaque
+@"\01LC" = external constant [11 x i8]         ; <[11 x i8]*> [#uses=1]
+
+define i8* @InArgMsgField(%struct.argument_t* %arg, i8* %str) nounwind  {
+entry:
+       %who = alloca [20 x i8]         ; <[20 x i8]*> [#uses=1]
+       %who1 = getelementptr [20 x i8]* %who, i32 0, i32 0             ; <i8*> [#uses=2]
+       call void @llvm.memset.i32( i8* %who1, i8 0, i32 20, i32 1 )
+       call void @llvm.memcpy.i32( i8* %who1, i8* getelementptr ([11 x i8]* @"\01LC", i32 0, i32 0), i32 11, i32 1 )
+       unreachable
+}
+
+declare void @llvm.memset.i32(i8*, i8, i32, i32) nounwind 
+
+declare void @llvm.memcpy.i32(i8*, i8*, i32, i32) nounwind