2016-12-03 01:48:48 +08:00
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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
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; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=-bmi | FileCheck %s --check-prefix=NO_BMI
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; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+bmi | FileCheck %s --check-prefix=BMI
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; Clear high bits via shift, set them with xor (not), then mask them off.
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define i32 @shrink_xor_constant1(i32 %x) {
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; NO_BMI-LABEL: shrink_xor_constant1:
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; NO_BMI: # BB#0:
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; NO_BMI-NEXT: shrl $31, %edi
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; NO_BMI-NEXT: notl %edi
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; NO_BMI-NEXT: andl $1, %edi
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; NO_BMI-NEXT: movl %edi, %eax
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; NO_BMI-NEXT: retq
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;
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; BMI-LABEL: shrink_xor_constant1:
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; BMI: # BB#0:
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; BMI-NEXT: shrl $31, %edi
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; BMI-NEXT: movl $1, %eax
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; BMI-NEXT: andnl %eax, %edi, %eax
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; BMI-NEXT: retq
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;
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%sh = lshr i32 %x, 31
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%not = xor i32 %sh, -1
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%and = and i32 %not, 1
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ret i32 %and
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}
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; Clear low bits via shift, set them with xor (not), then mask them off.
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define i8 @shrink_xor_constant2(i8 %x) {
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; NO_BMI-LABEL: shrink_xor_constant2:
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; NO_BMI: # BB#0:
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; NO_BMI-NEXT: shlb $5, %dil
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; NO_BMI-NEXT: notb %dil
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; NO_BMI-NEXT: andb $-32, %dil
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; NO_BMI-NEXT: movl %edi, %eax
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; NO_BMI-NEXT: retq
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;
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2016-12-03 01:50:14 +08:00
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; BMI-LABEL: shrink_xor_constant2:
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2016-12-03 01:48:48 +08:00
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; BMI: # BB#0:
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; BMI-NEXT: shlb $5, %dil
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; BMI-NEXT: notb %dil
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; BMI-NEXT: andb $-32, %dil
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; BMI-NEXT: movl %edi, %eax
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; BMI-NEXT: retq
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;
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%sh = shl i8 %x, 5
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%not = xor i8 %sh, -1
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%and = and i8 %not, 224 ; 0xE0
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ret i8 %and
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}
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