Teach ConvertUsesToScalar to handle memset, allowing it to handle 
crazy cases like:

struct f {  int A, B, C, D, E, F; };
short test4() {
  struct f A;
  A.A = 1;
  memset(&A.B, 2, 12);
  return A.C;
}



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63596 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Transforms/ScalarRepl/memset-aggregate.ll b/test/Transforms/ScalarRepl/memset-aggregate.ll
index 4febda5..b7b3352 100644
--- a/test/Transforms/ScalarRepl/memset-aggregate.ll
+++ b/test/Transforms/ScalarRepl/memset-aggregate.ll
@@ -1,6 +1,7 @@
 ; PR1226
 ; RUN: llvm-as < %s | opt -scalarrepl | llvm-dis | grep {ret i32 16843009}
 ; RUN: llvm-as < %s | opt -scalarrepl | llvm-dis | not grep alloca
+; RUN: llvm-as < %s | opt -scalarrepl -instcombine | llvm-dis | grep {ret i16 514}
 
 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"
 target triple = "i686-apple-darwin8"
@@ -46,3 +47,20 @@
 	%tmp7 = load i32* %tmp6		; <i32> [#uses=1]
 	ret i32 %tmp7
 }
+
+
+	%struct.f = type { i32, i32, i32, i32, i32, i32 }
+
+define i16 @test4() nounwind {
+entry:
+	%A = alloca %struct.f, align 8		; <%struct.f*> [#uses=3]
+	%0 = getelementptr %struct.f* %A, i32 0, i32 0		; <i32*> [#uses=1]
+	store i32 1, i32* %0, align 8
+	%1 = getelementptr %struct.f* %A, i32 0, i32 1		; <i32*> [#uses=1]
+	%2 = bitcast i32* %1 to i8*		; <i8*> [#uses=1]
+	call void @llvm.memset.i32(i8* %2, i8 2, i32 12, i32 4)
+	%3 = getelementptr %struct.f* %A, i32 0, i32 2		; <i32*> [#uses=1]
+	%4 = load i32* %3, align 8		; <i32> [#uses=1]
+	%retval12 = trunc i32 %4 to i16		; <i16> [#uses=1]
+	ret i16 %retval12
+}