| ; 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 |
| } |
| |