llvm/test/CodeGen/XCore/memcpy.ll
Richard Osborne c26292d4dc [XCore] Target optimized library function __memcpy_4()
Summary:
If the src, dst and size of a memcpy are known to be 4 byte aligned we
can call __memcpy_4() instead of memcpy().

Reviewers: robertlytton

Reviewed By: robertlytton

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D2871

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202395 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-27 13:39:07 +00:00

33 lines
956 B
LLVM

; RUN: llc < %s -march=xcore | FileCheck %s
; Optimize memcpy to __memcpy_4 if src, dst and size are all 4 byte aligned.
define void @f1(i8* %dst, i8* %src, i32 %n) nounwind {
; CHECK-LABEL: f1:
; CHECK: bl __memcpy_4
entry:
%0 = shl i32 %n, 2
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %src, i32 %0, i32 4, i1 false)
ret void
}
; Can't optimize - size is not a multiple of 4.
define void @f2(i8* %dst, i8* %src, i32 %n) nounwind {
; CHECK-LABEL: f2:
; CHECK: bl memcpy
entry:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %src, i32 %n, i32 4, i1 false)
ret void
}
; Can't optimize - alignment is not a multiple of 4.
define void @f3(i8* %dst, i8* %src, i32 %n) nounwind {
; CHECK-LABEL: f3:
; CHECK: bl memcpy
entry:
%0 = shl i32 %n, 2
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %src, i32 %0, i32 2, i1 false)
ret void
}
declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32, i1) nounwind