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; RUN: llc < %s -march=x86 -mcpu=yonah | FileCheck %s
; rdar://5752025
; We want:
; CHECK: movl $42, %ecx
; CHECK-NEXT: movl 4(%esp), %eax
; CHECK-NEXT: andl $15, %eax
; CHECK-NEXT: cmovnel %ecx, %eax
; CHECK-NEXT: ret
;
; We don't want:
; movl 4(%esp), %eax
; movl %eax, %ecx # bad: extra copy
; andl $15, %ecx
; testl $15, %eax # bad: peep obstructed
; movl $42, %eax
; cmovel %ecx, %eax
; ret
;
; We also don't want:
; movl $15, %ecx # bad: larger encoding
; andl 4(%esp), %ecx
; movl $42, %eax
; cmovel %ecx, %eax
; ret
;
; We also don't want:
; movl 4(%esp), %ecx
; andl $15, %ecx
; testl %ecx, %ecx # bad: unnecessary test
; movl $42, %eax
; cmovel %ecx, %eax
; ret
define i32 @t1(i32 %X) nounwind {
entry:
%tmp2 = and i32 %X, 15 ; <i32> [#uses=2]
%tmp4 = icmp eq i32 %tmp2, 0 ; <i1> [#uses=1]
%retval = select i1 %tmp4, i32 %tmp2, i32 42 ; <i32> [#uses=1]
ret i32 %retval
}
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