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; RUN: opt -instcombine -S < %s | FileCheck %s
define i32 @test1(i32 %x) nounwind {
%and = and i32 %x, 31
%sub = sub i32 63, %and
ret i32 %sub
; CHECK: @test1
; CHECK-NEXT: and i32 %x, 31
; CHECK-NEXT: xor i32 %and, 63
; CHECK-NEXT: ret
}
declare i32 @llvm.ctlz.i32(i32, i1) nounwind readnone
define i32 @test2(i32 %x) nounwind {
%count = tail call i32 @llvm.ctlz.i32(i32 %x, i1 true) nounwind readnone
%sub = sub i32 31, %count
ret i32 %sub
; CHECK: @test2
; CHECK-NEXT: ctlz
; CHECK-NEXT: xor i32 %count, 31
; CHECK-NEXT: ret
}
define i32 @test3(i32 %x) nounwind {
%and = and i32 %x, 31
%sub = xor i32 31, %and
%add = add i32 %sub, 42
ret i32 %add
; CHECK: @test3
; CHECK-NEXT: and i32 %x, 31
; CHECK-NEXT: sub i32 73, %and
; CHECK-NEXT: ret
}
define i32 @test4(i32 %x) nounwind {
%sub = xor i32 %x, 2147483648
%add = add i32 %sub, 42
ret i32 %add
; CHECK: @test4
; CHECK-NEXT: add i32 %x, -2147483606
; CHECK-NEXT: ret
}
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