; RUN: opt < %s -basic-aa -dse -S | FileCheck %s target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" target triple = "x86_64-apple-macosx10.8.0" %struct.anon = type { i32, i32, i32 } @b = global %struct.anon { i32 1, i32 0, i32 0 }, align 4 @c = common global i32 0, align 4 @a = common global %struct.anon zeroinitializer, align 4 @.str = private unnamed_addr constant [4 x i8] c"%d\0A\00", align 1 declare i32 @printf(i8* nocapture, ...) nounwind declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i1) nounwind ; Make sure that the initial memcpy call does not go away ; because the volatile load is in the way. PR12899 ; CHECK: main_entry: ; CHECK-NEXT: tail call void @llvm.memcpy.p0i8.p0i8.i64 define i32 @main() nounwind uwtable ssp { main_entry: tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 4 bitcast (%struct.anon* @b to i8*), i8* align 4 bitcast (%struct.anon* @a to i8*), i64 12, i1 false) %0 = load volatile i32, i32* getelementptr inbounds (%struct.anon, %struct.anon* @b, i64 0, i32 0), align 4 store i32 %0, i32* @c, align 4 tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 4 bitcast (%struct.anon* @b to i8*), i8* align 4 bitcast (%struct.anon* @a to i8*), i64 12, i1 false) nounwind %call = tail call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i32 %0) nounwind ret i32 0 }