llvm-6502/test/CodeGen/ARM64/memset-to-bzero.ll
Tim Northover 7b837d8c75 ARM64: initial backend import
This adds a second implementation of the AArch64 architecture to LLVM,
accessible in parallel via the "arm64" triple. The plan over the
coming weeks & months is to merge the two into a single backend,
during which time thorough code review should naturally occur.

Everything will be easier with the target in-tree though, hence this
commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205090 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-29 10:18:08 +00:00

102 lines
2.7 KiB
LLVM

; RUN: llc %s -march arm64 -o - | FileCheck %s
; <rdar://problem/14199482> ARM64: Calls to bzero() replaced with calls to memset()
; CHECK: @fct1
; For small size (<= 256), we do not change memset to bzero.
; CHECK: memset
define void @fct1(i8* nocapture %ptr) {
entry:
tail call void @llvm.memset.p0i8.i64(i8* %ptr, i8 0, i64 256, i32 1, i1 false)
ret void
}
declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1)
; CHECK: @fct2
; When the size is bigger than 256, change into bzero.
; CHECK: bzero
define void @fct2(i8* nocapture %ptr) {
entry:
tail call void @llvm.memset.p0i8.i64(i8* %ptr, i8 0, i64 257, i32 1, i1 false)
ret void
}
; CHECK: @fct3
; For unknown size, change to bzero.
; CHECK: bzero
define void @fct3(i8* nocapture %ptr, i32 %unknown) {
entry:
%conv = sext i32 %unknown to i64
tail call void @llvm.memset.p0i8.i64(i8* %ptr, i8 0, i64 %conv, i32 1, i1 false)
ret void
}
; CHECK: @fct4
; Size <= 256, no change.
; CHECK: memset
define void @fct4(i8* %ptr) {
entry:
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 0, i64 256, i64 %tmp)
ret void
}
declare i8* @__memset_chk(i8*, i32, i64, i64)
declare i64 @llvm.objectsize.i64(i8*, i1)
; CHECK: @fct5
; Size > 256, change.
; CHECK: bzero
define void @fct5(i8* %ptr) {
entry:
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 0, i64 257, i64 %tmp)
ret void
}
; CHECK: @fct6
; Size = unknown, change.
; CHECK: bzero
define void @fct6(i8* %ptr, i32 %unknown) {
entry:
%conv = sext i32 %unknown to i64
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 0, i64 %conv, i64 %tmp)
ret void
}
; Next functions check that memset is not turned into bzero
; when the set constant is non-zero, whatever the given size.
; CHECK: @fct7
; memset with something that is not a zero, no change.
; CHECK: memset
define void @fct7(i8* %ptr) {
entry:
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 1, i64 256, i64 %tmp)
ret void
}
; CHECK: @fct8
; memset with something that is not a zero, no change.
; CHECK: memset
define void @fct8(i8* %ptr) {
entry:
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 1, i64 257, i64 %tmp)
ret void
}
; CHECK: @fct9
; memset with something that is not a zero, no change.
; CHECK: memset
define void @fct9(i8* %ptr, i32 %unknown) {
entry:
%conv = sext i32 %unknown to i64
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 1, i64 %conv, i64 %tmp)
ret void
}