; RUN: opt -basicaa -memcpyopt -instcombine -S < %s | FileCheck %s target datalayout = "e-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" define void @foo([8 x i64]* noalias nocapture sret dereferenceable(64) %sret) { entry-block: %a = alloca [8 x i64], align 8 %a.cast = bitcast [8 x i64]* %a to i8* call void @llvm.lifetime.start(i64 64, i8* %a.cast) call void @llvm.memset.p0i8.i64(i8* %a.cast, i8 0, i64 64, i32 8, i1 false) %sret.cast = bitcast [8 x i64]* %sret to i8* call void @llvm.memcpy.p0i8.p0i8.i64(i8* %sret.cast, i8* %a.cast, i64 64, i32 8, i1 false) call void @llvm.lifetime.end(i64 64, i8* %a.cast) ret void ; CHECK-LABEL: @foo( ; CHECK: %[[sret_cast:[^=]+]] = bitcast [8 x i64]* %sret to i8* ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %[[sret_cast]], i8 0, i64 64 ; CHECK-NOT: call void @llvm.memcpy ; CHECK: ret void } define void @bar([8 x i64]* noalias nocapture sret dereferenceable(64) %sret, [8 x i64]* noalias nocapture dereferenceable(64) %out) { entry-block: %a = alloca [8 x i64], align 8 %a.cast = bitcast [8 x i64]* %a to i8* call void @llvm.lifetime.start(i64 64, i8* %a.cast) call void @llvm.memset.p0i8.i64(i8* %a.cast, i8 0, i64 64, i32 8, i1 false) %sret.cast = bitcast [8 x i64]* %sret to i8* call void @llvm.memcpy.p0i8.p0i8.i64(i8* %sret.cast, i8* %a.cast, i64 64, i32 8, i1 false) call void @llvm.memset.p0i8.i64(i8* %a.cast, i8 42, i64 32, i32 8, i1 false) %out.cast = bitcast [8 x i64]* %out to i8* call void @llvm.memcpy.p0i8.p0i8.i64(i8* %out.cast, i8* %a.cast, i64 64, i32 8, i1 false) call void @llvm.lifetime.end(i64 64, i8* %a.cast) ret void ; CHECK-LABEL: @bar( ; CHECK: %[[a:[^=]+]] = alloca [8 x i64] ; CHECK: %[[a_cast:[^=]+]] = bitcast [8 x i64]* %[[a]] to i8* ; CHECK: call void @llvm.memset.p0i8.i64(i8* %[[a_cast]], i8 0, i64 64 ; CHECK: %[[sret_cast:[^=]+]] = bitcast [8 x i64]* %sret to i8* ; CHECK: call void @llvm.memset.p0i8.i64(i8* %[[sret_cast]], i8 0, i64 64 ; CHECK: call void @llvm.memset.p0i8.i64(i8* %[[a_cast]], i8 42, i64 32 ; CHECK: %[[out_cast:[^=]+]] = bitcast [8 x i64]* %out to i8* ; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %[[out_cast]], i8* %[[a_cast]], i64 64 ; CHECK-NOT: call void @llvm.memcpy ; CHECK: ret void } declare void @llvm.lifetime.start(i64, i8* nocapture) nounwind declare void @llvm.lifetime.end(i64, i8* nocapture) nounwind declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i32, i1) nounwind declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) nounwind