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; RUN: llc < %s -mtriple=arm-apple-darwin | FileCheck %s
define i32 @f(i32 %a, i32 %b) nounwind ssp {
entry:
; CHECK-LABEL: f:
; CHECK: subs
; CHECK-NOT: cmp
%cmp = icmp sgt i32 %a, %b
%sub = sub nsw i32 %a, %b
%sub. = select i1 %cmp, i32 %sub, i32 0
ret i32 %sub.
}
define i32 @g(i32 %a, i32 %b) nounwind ssp {
entry:
; CHECK-LABEL: g:
; CHECK: subs
; CHECK-NOT: cmp
%cmp = icmp slt i32 %a, %b
%sub = sub nsw i32 %b, %a
%sub. = select i1 %cmp, i32 %sub, i32 0
ret i32 %sub.
}
define i32 @h(i32 %a, i32 %b) nounwind ssp {
entry:
; CHECK-LABEL: h:
; CHECK: subs
; CHECK-NOT: cmp
%cmp = icmp sgt i32 %a, 3
%sub = sub nsw i32 %a, 3
%sub. = select i1 %cmp, i32 %sub, i32 %b
ret i32 %sub.
}
; rdar://11725965
define i32 @i(i32 %a, i32 %b) nounwind readnone ssp {
entry:
; CHECK-LABEL: i:
; CHECK: subs
; CHECK-NOT: cmp
%cmp = icmp ult i32 %a, %b
%sub = sub i32 %b, %a
%sub. = select i1 %cmp, i32 %sub, i32 0
ret i32 %sub.
}
; If CPSR is live-out, we can't remove cmp if there exists
; a swapped sub.
define i32 @j(i32 %a, i32 %b) nounwind {
entry:
; CHECK-LABEL: j:
; CHECK: sub
; CHECK: cmp
%cmp = icmp eq i32 %b, %a
%sub = sub nsw i32 %a, %b
br i1 %cmp, label %if.then, label %if.else
if.then:
%cmp2 = icmp sgt i32 %b, %a
%sel = select i1 %cmp2, i32 %sub, i32 %a
ret i32 %sel
if.else:
ret i32 %sub
}
; If the sub/rsb instruction is predicated, we can't use the flags.
; <rdar://problem/12263428>
; Test case from MultiSource/Benchmarks/Ptrdist/bc/number.s
; CHECK: bc_raise
; CHECK: rsbeq
; CHECK: cmp
define i32 @bc_raise() nounwind ssp {
entry:
%val.2.i = select i1 undef, i32 0, i32 undef
%sub.i = sub nsw i32 0, %val.2.i
%retval.0.i = select i1 undef, i32 %val.2.i, i32 %sub.i
%cmp1 = icmp eq i32 %retval.0.i, 0
br i1 %cmp1, label %land.lhs.true, label %if.end11
land.lhs.true: ; preds = %num2long.exit
ret i32 17
if.end11: ; preds = %num2long.exit
ret i32 23
}
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