llvm-6502/test/Transforms/MemCpyOpt/memset-memcpy-to-2x-memset.ll
Ahmed Bougacha 8081057fca [MemCpyOpt] Turn memcpy from just-memset'd source into memset.
There's no point in copying around constants, so, when all else fails,
we can still transform memcpy of memset into two independent memsets.

To quote the example, we can turn:
  memset(dst1, c, dst1_size);
  memcpy(dst2, dst1, dst2_size);
into:
  memset(dst1, c, dst1_size);
  memset(dst2, c, dst2_size);
When dst2_size <= dst1_size.

Like r235232 for copy constructors, this can occur in move constructors.

Differential Revision: http://reviews.llvm.org/D9682


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237506 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-16 01:32:26 +00:00

102 lines
5.0 KiB
LLVM

; RUN: opt -memcpyopt -S %s | FileCheck %s
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
; CHECK-LABEL: define void @test(
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 1, i1 false)
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst2, i8 %c, i64 128, i32 8, i1 false)
; CHECK-NEXT: ret void
define void @test(i8* %dst1, i8* %dst2, i8 %c) {
call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 1, i1 false)
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %dst1, i64 128, i32 8, i1 false)
ret void
}
; CHECK-LABEL: define void @test_smaller_memcpy(
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 1, i1 false)
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst2, i8 %c, i64 100, i32 1, i1 false)
; CHECK-NEXT: ret void
define void @test_smaller_memcpy(i8* %dst1, i8* %dst2, i8 %c) {
call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 1, i1 false)
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %dst1, i64 100, i32 1, i1 false)
ret void
}
; CHECK-LABEL: define void @test_smaller_memset(
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 100, i32 1, i1 false)
; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %dst1, i64 128, i32 1, i1 false)
; CHECK-NEXT: ret void
define void @test_smaller_memset(i8* %dst1, i8* %dst2, i8 %c) {
call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 100, i32 1, i1 false)
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %dst1, i64 128, i32 1, i1 false)
ret void
}
; CHECK-LABEL: define void @test_align_memset(
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 8, i1 false)
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst2, i8 %c, i64 128, i32 1, i1 false)
; CHECK-NEXT: ret void
define void @test_align_memset(i8* %dst1, i8* %dst2, i8 %c) {
call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 8, i1 false)
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %dst1, i64 128, i32 1, i1 false)
ret void
}
; CHECK-LABEL: define void @test_different_types(
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 8, i1 false)
; CHECK-NEXT: call void @llvm.memset.p0i8.i32(i8* %dst2, i8 %c, i32 100, i32 1, i1 false)
; CHECK-NEXT: ret void
define void @test_different_types(i8* %dst1, i8* %dst2, i8 %c) {
call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 8, i1 false)
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst2, i8* %dst1, i32 100, i32 1, i1 false)
ret void
}
; CHECK-LABEL: define void @test_different_types_2(
; CHECK-NEXT: call void @llvm.memset.p0i8.i32(i8* %dst1, i8 %c, i32 128, i32 8, i1 false)
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst2, i8 %c, i64 100, i32 1, i1 false)
; CHECK-NEXT: ret void
define void @test_different_types_2(i8* %dst1, i8* %dst2, i8 %c) {
call void @llvm.memset.p0i8.i32(i8* %dst1, i8 %c, i32 128, i32 8, i1 false)
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %dst1, i64 100, i32 1, i1 false)
ret void
}
; CHECK-LABEL: define void @test_different_source_gep(
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 1, i1 false)
; CHECK-NEXT: %p = getelementptr i8, i8* %dst1, i64 64
; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %p, i64 64, i32 1, i1 false)
; CHECK-NEXT: ret void
define void @test_different_source_gep(i8* %dst1, i8* %dst2, i8 %c) {
call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 1, i1 false)
; FIXME: We could optimize this as well.
%p = getelementptr i8, i8* %dst1, i64 64
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %p, i64 64, i32 1, i1 false)
ret void
}
; CHECK-LABEL: define void @test_variable_size_1(
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 %dst1_size, i32 1, i1 false)
; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %dst1, i64 128, i32 1, i1 false)
; CHECK-NEXT: ret void
define void @test_variable_size_1(i8* %dst1, i64 %dst1_size, i8* %dst2, i8 %c) {
call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 %dst1_size, i32 1, i1 false)
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %dst1, i64 128, i32 1, i1 false)
ret void
}
; CHECK-LABEL: define void @test_variable_size_2(
; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 1, i1 false)
; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %dst1, i64 %dst2_size, i32 1, i1 false)
; CHECK-NEXT: ret void
define void @test_variable_size_2(i8* %dst1, i8* %dst2, i64 %dst2_size, i8 %c) {
call void @llvm.memset.p0i8.i64(i8* %dst1, i8 %c, i64 128, i32 1, i1 false)
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst2, i8* %dst1, i64 %dst2_size, i32 1, i1 false)
ret void
}
declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1)
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i32, i1)
declare void @llvm.memset.p0i8.i32(i8* nocapture, i8, i32, i32, i1)
declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1)