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; RUN: llc -mtriple=arm-eabi -mattr=+v4t %s -o - | FileCheck %s
;; Integer absolute value, should produce something as good as: ARM:
;; movs r0, r0
;; rsbmi r0, r0, #0
;; bx lr
define i32 @test(i32 %a) {
%tmp1neg = sub i32 0, %a
%b = icmp sgt i32 %a, -1
%abs = select i1 %b, i32 %a, i32 %tmp1neg
ret i32 %abs
; CHECK: cmp
; CHECK: rsbmi r0, r0, #0
; CHECK: bx lr
}
; rdar://11633193
;; 3 instructions will be generated for abs(a-b):
;; subs
;; rsbmi
;; bx
define i32 @test2(i32 %a, i32 %b) nounwind readnone ssp {
entry:
; CHECK: test2
; CHECK: subs
; CHECK-NEXT: rsbmi
; CHECK-NEXT: bx
%sub = sub nsw i32 %a, %b
%cmp = icmp sgt i32 %sub, -1
%sub1 = sub nsw i32 0, %sub
%cond = select i1 %cmp, i32 %sub, i32 %sub1
ret i32 %cond
}
define i64 @test3(i64 %a) {
; CHECK-LABEL: test3:
; CHECK: @ %bb.0:
; CHECK-NEXT: eor r0, r0, r1, asr #31
; CHECK-NEXT: eor r2, r1, r1, asr #31
; CHECK-NEXT: subs r0, r0, r1, asr #31
; CHECK-NEXT: sbc r1, r2, r1, asr #31
; CHECK-NEXT: bx lr
%tmp1neg = sub i64 0, %a
%b = icmp sgt i64 %a, -1
%abs = select i1 %b, i64 %a, i64 %tmp1neg
ret i64 %abs
}
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