1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2; RUN: opt < %s -S -passes=memcpyopt -verify-memoryssa | FileCheck %s 3target datalayout = "e-i64:64-f80:128-n8:16:32:64-S128" 4 5declare void @llvm.memcpy.p0.p0.i64(ptr nocapture, ptr nocapture readonly, i64, i1) unnamed_addr nounwind 6declare void @llvm.memset.p0.i64(ptr nocapture, i8, i64, i1) nounwind 7 8; all bytes of %dst that are touch by the memset are dereferenceable 9define void @must_remove_memcpy(ptr noalias nocapture writable dereferenceable(4096) %dst) nofree nosync { 10; CHECK-LABEL: @must_remove_memcpy( 11; CHECK-NEXT: [[SRC:%.*]] = alloca [4096 x i8], align 1 12; CHECK-NEXT: call void @llvm.memset.p0.i64(ptr [[DST:%.*]], i8 0, i64 4096, i1 false) 13; CHECK-NEXT: ret void 14; 15 %src = alloca [4096 x i8], align 1 16 call void @llvm.memset.p0.i64(ptr %src, i8 0, i64 4096, i1 false) 17 call void @llvm.memcpy.p0.p0.i64(ptr %dst, ptr %src, i64 4096, i1 false) #2 18 ret void 19} 20 21; memset touch more bytes than those guaranteed to be dereferenceable 22; We can't remove the memcpy, but we can turn it into an independent memset. 23define void @must_not_remove_memcpy(ptr noalias nocapture writable dereferenceable(1024) %dst) nofree nosync { 24; CHECK-LABEL: @must_not_remove_memcpy( 25; CHECK-NEXT: [[SRC:%.*]] = alloca [4096 x i8], align 1 26; CHECK-NEXT: call void @llvm.memset.p0.i64(ptr [[SRC]], i8 0, i64 4096, i1 false) 27; CHECK-NEXT: call void @llvm.memset.p0.i64(ptr [[DST:%.*]], i8 0, i64 4096, i1 false) 28; CHECK-NEXT: ret void 29; 30 %src = alloca [4096 x i8], align 1 31 call void @llvm.memset.p0.i64(ptr %src, i8 0, i64 4096, i1 false) 32 call void @llvm.memcpy.p0.p0.i64(ptr %dst, ptr %src, i64 4096, i1 false) #2 33 ret void 34} 35