1; RUN: opt < %s -passes=dse -S | FileCheck %s 2 3target 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" 4target triple = "x86_64-apple-macosx10.8.0" 5 6%struct.anon = type { i32, i32, i32 } 7@b = global %struct.anon { i32 1, i32 0, i32 0 }, align 4 8@c = common global i32 0, align 4 9@a = common global %struct.anon zeroinitializer, align 4 10@.str = private unnamed_addr constant [4 x i8] c"%d\0A\00", align 1 11 12declare i32 @printf(ptr nocapture, ...) nounwind 13declare void @llvm.memcpy.p0.p0.i64(ptr nocapture, ptr nocapture, i64, i1) nounwind 14 15 16; Make sure that the initial memcpy call does not go away 17; because the volatile load is in the way. PR12899 18 19; CHECK: main_entry: 20; CHECK-NEXT: tail call void @llvm.memcpy.p0.p0.i64 21 22define i32 @main() nounwind uwtable ssp { 23main_entry: 24 tail call void @llvm.memcpy.p0.p0.i64(ptr align 4 @b, ptr align 4 @a, i64 12, i1 false) 25 %0 = load volatile i32, ptr @b, align 4 26 store i32 %0, ptr @c, align 4 27 tail call void @llvm.memcpy.p0.p0.i64(ptr align 4 @b, ptr align 4 @a, i64 12, i1 false) nounwind 28 %call = tail call i32 (ptr, ...) @printf(ptr @.str, i32 %0) nounwind 29 ret i32 0 30} 31