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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=-bmi | FileCheck %s --check-prefix=ALL --check-prefix=NO_BMI
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+bmi | FileCheck %s --check-prefix=ALL --check-prefix=BMI
; Clear high bits via shift, set them with xor (not), then mask them off.
define i32 @shrink_xor_constant1(i32 %x) {
; ALL-LABEL: shrink_xor_constant1:
; ALL: # BB#0:
; ALL-NEXT: shrl $31, %edi
; ALL-NEXT: xorl $1, %edi
; ALL-NEXT: movl %edi, %eax
; ALL-NEXT: retq
;
%sh = lshr i32 %x, 31
%not = xor i32 %sh, -1
%and = and i32 %not, 1
ret i32 %and
}
; Clear low bits via shift, set them with xor (not), then mask them off.
define i8 @shrink_xor_constant2(i8 %x) {
; ALL-LABEL: shrink_xor_constant2:
; ALL: # BB#0:
; ALL-NEXT: shlb $5, %dil
; ALL-NEXT: xorb $-32, %dil
; ALL-NEXT: movl %edi, %eax
; ALL-NEXT: retq
;
%sh = shl i8 %x, 5
%not = xor i8 %sh, -1
%and = and i8 %not, 224 ; 0xE0
ret i8 %and
}
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