; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt -memcpyopt -S %s -enable-memcpyopt-memoryssa=0 | FileCheck %s ; RUN: opt -memcpyopt -S %s -enable-memcpyopt-memoryssa=1 -verify-memoryssa | FileCheck %s ; memset -> memcpy forwarding, if memcpy is larger than memset, but trailing ; bytes are known to be undef. %T = type { i64, i32, i32 } define void @test_alloca(i8* %result) { ; CHECK-LABEL: @test_alloca( ; CHECK-NEXT: [[A:%.*]] = alloca [[T:%.*]], align 8 ; CHECK-NEXT: [[B:%.*]] = bitcast %T* [[A]] to i8* ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 8 [[B]], i8 0, i64 12, i1 false) ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* [[RESULT:%.*]], i8 0, i64 12, i1 false) ; CHECK-NEXT: ret void ; %a = alloca %T, align 8 %b = bitcast %T* %a to i8* call void @llvm.memset.p0i8.i64(i8* align 8 %b, i8 0, i64 12, i1 false) call void @llvm.memcpy.p0i8.p0i8.i64(i8* %result, i8* align 8 %b, i64 16, i1 false) ret void } define void @test_alloca_with_lifetimes(i8* %result) { ; CHECK-LABEL: @test_alloca_with_lifetimes( ; CHECK-NEXT: [[A:%.*]] = alloca [[T:%.*]], align 8 ; CHECK-NEXT: [[B:%.*]] = bitcast %T* [[A]] to i8* ; CHECK-NEXT: call void @llvm.lifetime.start.p0i8(i64 16, i8* [[B]]) ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 8 [[B]], i8 0, i64 12, i1 false) ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* [[RESULT:%.*]], i8 0, i64 12, i1 false) ; CHECK-NEXT: call void @llvm.lifetime.end.p0i8(i64 16, i8* [[B]]) ; CHECK-NEXT: ret void ; %a = alloca %T, align 8 %b = bitcast %T* %a to i8* call void @llvm.lifetime.start.p0i8(i64 16, i8* %b) call void @llvm.memset.p0i8.i64(i8* align 8 %b, i8 0, i64 12, i1 false) call void @llvm.memcpy.p0i8.p0i8.i64(i8* %result, i8* align 8 %b, i64 16, i1 false) call void @llvm.lifetime.end.p0i8(i64 16, i8* %b) ret void } define void @test_malloc_with_lifetimes(i8* %result) { ; CHECK-LABEL: @test_malloc_with_lifetimes( ; CHECK-NEXT: [[A:%.*]] = call i8* @malloc(i64 16) ; CHECK-NEXT: call void @llvm.lifetime.start.p0i8(i64 16, i8* [[A]]) ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 8 [[A]], i8 0, i64 12, i1 false) ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* [[RESULT:%.*]], i8 0, i64 12, i1 false) ; CHECK-NEXT: call void @llvm.lifetime.end.p0i8(i64 16, i8* [[A]]) ; CHECK-NEXT: call void @free(i8* [[A]]) ; CHECK-NEXT: ret void ; %a = call i8* @malloc(i64 16) call void @llvm.lifetime.start.p0i8(i64 16, i8* %a) call void @llvm.memset.p0i8.i64(i8* align 8 %a, i8 0, i64 12, i1 false) call void @llvm.memcpy.p0i8.p0i8.i64(i8* %result, i8* align 8 %a, i64 16, i1 false) call void @llvm.lifetime.end.p0i8(i64 16, i8* %a) call void @free(i8* %a) ret void } ; memcpy size is larger than lifetime, don't optimize. define void @test_copy_larger_than_lifetime_size(i8* %result) { ; CHECK-LABEL: @test_copy_larger_than_lifetime_size( ; CHECK-NEXT: [[A:%.*]] = call i8* @malloc(i64 16) ; CHECK-NEXT: call void @llvm.lifetime.start.p0i8(i64 12, i8* [[A]]) ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 8 [[A]], i8 0, i64 12, i1 false) ; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* [[RESULT:%.*]], i8* align 8 [[A]], i64 16, i1 false) ; CHECK-NEXT: call void @llvm.lifetime.end.p0i8(i64 12, i8* [[A]]) ; CHECK-NEXT: call void @free(i8* [[A]]) ; CHECK-NEXT: ret void ; %a = call i8* @malloc(i64 16) call void @llvm.lifetime.start.p0i8(i64 12, i8* %a) call void @llvm.memset.p0i8.i64(i8* align 8 %a, i8 0, i64 12, i1 false) call void @llvm.memcpy.p0i8.p0i8.i64(i8* %result, i8* align 8 %a, i64 16, i1 false) call void @llvm.lifetime.end.p0i8(i64 12, i8* %a) call void @free(i8* %a) ret void } ; The trailing bytes are not known to be undef, we can't ignore them. define void @test_not_undef_memory(i8* %result, i8* %input) { ; CHECK-LABEL: @test_not_undef_memory( ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 8 [[INPUT:%.*]], i8 0, i64 12, i1 false) ; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* [[RESULT:%.*]], i8* align 8 [[INPUT]], i64 16, i1 false) ; CHECK-NEXT: ret void ; call void @llvm.memset.p0i8.i64(i8* align 8 %input, i8 0, i64 12, i1 false) call void @llvm.memcpy.p0i8.p0i8.i64(i8* %result, i8* align 8 %input, i64 16, i1 false) ret void } ; Memset is volatile, memcpy is not. Can be optimized. define void @test_volatile_memset(i8* %result) { ; CHECK-LABEL: @test_volatile_memset( ; CHECK-NEXT: [[A:%.*]] = alloca [[T:%.*]], align 8 ; CHECK-NEXT: [[B:%.*]] = bitcast %T* [[A]] to i8* ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 8 [[B]], i8 0, i64 12, i1 true) ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* [[RESULT:%.*]], i8 0, i64 12, i1 false) ; CHECK-NEXT: ret void ; %a = alloca %T, align 8 %b = bitcast %T* %a to i8* call void @llvm.memset.p0i8.i64(i8* align 8 %b, i8 0, i64 12, i1 true) call void @llvm.memcpy.p0i8.p0i8.i64(i8* %result, i8* align 8 %b, i64 16, i1 false) ret void } ; Memcpy is volatile, memset is not. Cannot be optimized. define void @test_volatile_memcpy(i8* %result) { ; CHECK-LABEL: @test_volatile_memcpy( ; CHECK-NEXT: [[A:%.*]] = alloca [[T:%.*]], align 8 ; CHECK-NEXT: [[B:%.*]] = bitcast %T* [[A]] to i8* ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 8 [[B]], i8 0, i64 12, i1 false) ; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* [[RESULT:%.*]], i8* align 8 [[B]], i64 16, i1 true) ; CHECK-NEXT: ret void ; %a = alloca %T, align 8 %b = bitcast %T* %a to i8* call void @llvm.memset.p0i8.i64(i8* align 8 %b, i8 0, i64 12, i1 false) call void @llvm.memcpy.p0i8.p0i8.i64(i8* %result, i8* align 8 %b, i64 16, i1 true) ret void } ; Write between memset and memcpy, can't optimize. define void @test_write_between(i8* %result) { ; CHECK-LABEL: @test_write_between( ; CHECK-NEXT: [[A:%.*]] = alloca [[T:%.*]], align 8 ; CHECK-NEXT: [[B:%.*]] = bitcast %T* [[A]] to i8* ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 8 [[B]], i8 0, i64 12, i1 false) ; CHECK-NEXT: store i8 -1, i8* [[B]], align 1 ; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* [[RESULT:%.*]], i8* align 8 [[B]], i64 16, i1 false) ; CHECK-NEXT: ret void ; %a = alloca %T, align 8 %b = bitcast %T* %a to i8* call void @llvm.memset.p0i8.i64(i8* align 8 %b, i8 0, i64 12, i1 false) store i8 -1, i8* %b call void @llvm.memcpy.p0i8.p0i8.i64(i8* %result, i8* align 8 %b, i64 16, i1 false) ret void } ; A write prior to the memset, which is part of the memset region. ; We could optimize this, but currently don't, because the used memory location is imprecise. define void @test_write_before_memset_in_memset_region(i8* %result) { ; CHECK-LABEL: @test_write_before_memset_in_memset_region( ; CHECK-NEXT: [[A:%.*]] = alloca [[T:%.*]], align 8 ; CHECK-NEXT: [[B:%.*]] = bitcast %T* [[A]] to i8* ; CHECK-NEXT: store i8 -1, i8* [[B]], align 1 ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 8 [[B]], i8 0, i64 8, i1 false) ; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* [[RESULT:%.*]], i8* align 8 [[B]], i64 16, i1 false) ; CHECK-NEXT: ret void ; %a = alloca %T, align 8 %b = bitcast %T* %a to i8* store i8 -1, i8* %b call void @llvm.memset.p0i8.i64(i8* align 8 %b, i8 0, i64 8, i1 false) call void @llvm.memcpy.p0i8.p0i8.i64(i8* %result, i8* align 8 %b, i64 16, i1 false) ret void } ; A write prior to the memset, which is part of the memcpy (but not memset) region. ; This cannot be optimized. define void @test_write_before_memset_in_memcpy_region(i8* %result) { ; CHECK-LABEL: @test_write_before_memset_in_memcpy_region( ; CHECK-NEXT: [[A:%.*]] = alloca [[T:%.*]], align 8 ; CHECK-NEXT: [[B:%.*]] = bitcast %T* [[A]] to i8* ; CHECK-NEXT: [[C:%.*]] = getelementptr inbounds [[T]], %T* [[A]], i64 0, i32 2 ; CHECK-NEXT: store i32 -1, i32* [[C]], align 4 ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 8 [[B]], i8 0, i64 8, i1 false) ; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* [[RESULT:%.*]], i8* align 8 [[B]], i64 16, i1 false) ; CHECK-NEXT: ret void ; %a = alloca %T, align 8 %b = bitcast %T* %a to i8* %c = getelementptr inbounds %T, %T* %a, i64 0, i32 2 store i32 -1, i32* %c call void @llvm.memset.p0i8.i64(i8* align 8 %b, i8 0, i64 8, i1 false) call void @llvm.memcpy.p0i8.p0i8.i64(i8* %result, i8* align 8 %b, i64 16, i1 false) ret void } ; A write prior to the memset, which is part of both the memset and memcpy regions. ; This cannot be optimized. define void @test_write_before_memset_in_both_regions(i8* %result) { ; CHECK-LABEL: @test_write_before_memset_in_both_regions( ; CHECK-NEXT: [[A:%.*]] = alloca [[T:%.*]], align 8 ; CHECK-NEXT: [[B:%.*]] = bitcast %T* [[A]] to i8* ; CHECK-NEXT: [[C:%.*]] = getelementptr inbounds [[T]], %T* [[A]], i64 0, i32 1 ; CHECK-NEXT: store i32 -1, i32* [[C]], align 4 ; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 8 [[B]], i8 0, i64 10, i1 false) ; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* [[RESULT:%.*]], i8* align 8 [[B]], i64 16, i1 false) ; CHECK-NEXT: ret void ; %a = alloca %T, align 8 %b = bitcast %T* %a to i8* %c = getelementptr inbounds %T, %T* %a, i64 0, i32 1 store i32 -1, i32* %c call void @llvm.memset.p0i8.i64(i8* align 8 %b, i8 0, i64 10, i1 false) call void @llvm.memcpy.p0i8.p0i8.i64(i8* %result, i8* align 8 %b, i64 16, i1 false) ret void } declare i8* @malloc(i64) declare void @free(i8*) declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i1) declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i1) declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture) declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture)