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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=instcombine -S | FileCheck %s
declare void @use(i8)
declare void @use_i1(i1)
declare void @use_i1_vec(<2 x i1>)
; (X & -X) < 0 --> X == MinSignC
; (X & X) > -1 --> X != MinSignC
define i1 @pow2_or_zero_is_negative(i8 %x) {
; CHECK-LABEL: @pow2_or_zero_is_negative(
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[X:%.*]], -128
; CHECK-NEXT: [[CMP_2:%.*]] = icmp eq i8 [[X]], -128
; CHECK-NEXT: call void @use_i1(i1 [[CMP_2]])
; CHECK-NEXT: ret i1 [[CMP]]
;
%neg = sub i8 0, %x
%pow2_or_zero = and i8 %x, %neg
%cmp = icmp slt i8 %pow2_or_zero, 0
%cmp.2 = icmp ugt i8 %pow2_or_zero, 127
call void @use_i1(i1 %cmp.2)
ret i1 %cmp
}
define i1 @pow2_or_zero_is_negative_commute(i8 %A) {
; CHECK-LABEL: @pow2_or_zero_is_negative_commute(
; CHECK-NEXT: [[X:%.*]] = mul i8 [[A:%.*]], 42
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[X]], -128
; CHECK-NEXT: ret i1 [[CMP]]
;
%x = mul i8 42, %A ; thwart complexity-based canonicalization
%neg = sub i8 0, %x
%pow2_or_zero = and i8 %neg, %x
%cmp = icmp slt i8 %pow2_or_zero, 0
ret i1 %cmp
}
define <2 x i1> @pow2_or_zero_is_negative_vec(<2 x i8> %x) {
; CHECK-LABEL: @pow2_or_zero_is_negative_vec(
; CHECK-NEXT: [[CMP:%.*]] = icmp eq <2 x i8> [[X:%.*]], <i8 -128, i8 -128>
; CHECK-NEXT: [[CMP_2:%.*]] = icmp eq <2 x i8> [[X]], <i8 -128, i8 -128>
; CHECK-NEXT: call void @use_i1_vec(<2 x i1> [[CMP_2]])
; CHECK-NEXT: ret <2 x i1> [[CMP]]
;
%neg = sub <2 x i8> <i8 0, i8 0>, %x
%pow2_or_zero = and <2 x i8> %x, %neg
%cmp = icmp slt <2 x i8> %pow2_or_zero, <i8 0, i8 0>
%cmp.2 = icmp ugt <2 x i8> %pow2_or_zero, <i8 127, i8 127>
call void @use_i1_vec(<2 x i1> %cmp.2)
ret <2 x i1> %cmp
}
define <2 x i1> @pow2_or_zero_is_negative_vec_commute(<2 x i8> %A) {
; CHECK-LABEL: @pow2_or_zero_is_negative_vec_commute(
; CHECK-NEXT: [[X:%.*]] = mul <2 x i8> [[A:%.*]], <i8 42, i8 42>
; CHECK-NEXT: [[CMP:%.*]] = icmp eq <2 x i8> [[X]], <i8 -128, i8 -128>
; CHECK-NEXT: ret <2 x i1> [[CMP]]
;
%x = mul <2 x i8> <i8 42, i8 42>, %A ; thwart complexity-based canonicalization
%neg = sub <2 x i8> <i8 0, i8 0>, %x
%pow2_or_zero = and <2 x i8> %neg, %x
%cmp = icmp slt <2 x i8> %pow2_or_zero, <i8 0, i8 0>
ret <2 x i1> %cmp
}
define i1 @pow2_or_zero_is_not_negative(i8 %x) {
; CHECK-LABEL: @pow2_or_zero_is_not_negative(
; CHECK-NEXT: [[CMP:%.*]] = icmp ne i8 [[X:%.*]], -128
; CHECK-NEXT: [[CMP_2:%.*]] = icmp ne i8 [[X]], -128
; CHECK-NEXT: call void @use_i1(i1 [[CMP_2]])
; CHECK-NEXT: ret i1 [[CMP]]
;
%neg = sub i8 0, %x
%pow2_or_zero = and i8 %x, %neg
%cmp = icmp sgt i8 %pow2_or_zero, -1
%cmp.2 = icmp ult i8 %pow2_or_zero, -128
call void @use_i1(i1 %cmp.2)
ret i1 %cmp
}
define i1 @pow2_or_zero_is_not_negative_commute(i8 %A) {
; CHECK-LABEL: @pow2_or_zero_is_not_negative_commute(
; CHECK-NEXT: [[X:%.*]] = mul i8 [[A:%.*]], 42
; CHECK-NEXT: [[CMP:%.*]] = icmp ne i8 [[X]], -128
; CHECK-NEXT: ret i1 [[CMP]]
;
%x = mul i8 42, %A ; thwart complexity-based canonicalization
%neg = sub i8 0, %x
%pow2_or_zero = and i8 %neg, %x
%cmp = icmp sgt i8 %pow2_or_zero, -1
ret i1 %cmp
}
define <2 x i1> @pow2_or_zero_is_not_negative_vec(<2 x i8> %x) {
; CHECK-LABEL: @pow2_or_zero_is_not_negative_vec(
; CHECK-NEXT: [[CMP:%.*]] = icmp ne <2 x i8> [[X:%.*]], <i8 -128, i8 -128>
; CHECK-NEXT: [[CMP_2:%.*]] = icmp ne <2 x i8> [[X]], <i8 -128, i8 -128>
; CHECK-NEXT: call void @use_i1_vec(<2 x i1> [[CMP_2]])
; CHECK-NEXT: ret <2 x i1> [[CMP]]
;
%neg = sub <2 x i8> <i8 0, i8 0>, %x
%pow2_or_zero = and <2 x i8> %x, %neg
%cmp = icmp sgt <2 x i8> %pow2_or_zero, <i8 -1, i8 -1>
%cmp.2 = icmp ult <2 x i8> %pow2_or_zero, <i8 -128, i8 -128>
call void @use_i1_vec(<2 x i1> %cmp.2)
ret <2 x i1> %cmp
}
define <2 x i1> @pow2_or_zero_is_not_negative_vec_commute(<2 x i8> %A) {
; CHECK-LABEL: @pow2_or_zero_is_not_negative_vec_commute(
; CHECK-NEXT: [[X:%.*]] = mul <2 x i8> [[A:%.*]], <i8 42, i8 42>
; CHECK-NEXT: [[CMP:%.*]] = icmp ne <2 x i8> [[X]], <i8 -128, i8 -128>
; CHECK-NEXT: ret <2 x i1> [[CMP]]
;
%x = mul <2 x i8> <i8 42, i8 42>, %A ; thwart complexity-based canonicalization
%neg = sub <2 x i8> <i8 0, i8 0>, %x
%pow2_or_zero = and <2 x i8> %neg, %x
%cmp = icmp sgt <2 x i8> %pow2_or_zero, <i8 -1, i8 -1>
ret <2 x i1> %cmp
}
define i1 @pow2_or_zero_is_negative_extra_use(i8 %x) {
; CHECK-LABEL: @pow2_or_zero_is_negative_extra_use(
; CHECK-NEXT: [[NEG:%.*]] = sub i8 0, [[X:%.*]]
; CHECK-NEXT: call void @use(i8 [[NEG]])
; CHECK-NEXT: [[POW2_OR_ZERO:%.*]] = and i8 [[NEG]], [[X]]
; CHECK-NEXT: call void @use(i8 [[POW2_OR_ZERO]])
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[X]], -128
; CHECK-NEXT: ret i1 [[CMP]]
;
%neg = sub i8 0, %x
call void @use(i8 %neg)
%pow2_or_zero = and i8 %x, %neg
call void @use(i8 %pow2_or_zero)
%cmp = icmp slt i8 %pow2_or_zero, 0
ret i1 %cmp
}
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