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; RUN: llc < %s -march=x86-64 -o - | FileCheck %s
; Reuse the flags value from the add instructions instead of emitting separate
; testl instructions.
; Use the flags on the add.
; CHECK: add_zf:
; CHECK: addl (%rdi), %esi
; CHECK-NEXT: movl %edx, %eax
; CHECK-NEXT: cmovnsl %ecx, %eax
; CHECK-NEXT: ret
define i32 @add_zf(i32* %x, i32 %y, i32 %a, i32 %b) nounwind {
%tmp2 = load i32* %x, align 4 ; <i32> [#uses=1]
%tmp4 = add i32 %tmp2, %y ; <i32> [#uses=1]
%tmp5 = icmp slt i32 %tmp4, 0 ; <i1> [#uses=1]
%tmp.0 = select i1 %tmp5, i32 %a, i32 %b ; <i32> [#uses=1]
ret i32 %tmp.0
}
declare void @foo(i32)
; Don't use the flags result of the and here, since the and has no
; other use. A simple test is better.
; CHECK: bar:
; CHECK: testb $16, %dil
define void @bar(i32 %x) nounwind {
%y = and i32 %x, 16
%t = icmp eq i32 %y, 0
br i1 %t, label %true, label %false
true:
call void @foo(i32 %x)
ret void
false:
ret void
}
; Do use the flags result of the and here, since the and has another use.
; CHECK: qux:
; CHECK: andl $16, %edi
; CHECK-NEXT: jne
define void @qux(i32 %x) nounwind {
%y = and i32 %x, 16
%t = icmp eq i32 %y, 0
br i1 %t, label %true, label %false
true:
call void @foo(i32 %y)
ret void
false:
ret void
}
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