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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=instcombine -S < %s | FileCheck %s
; Given:
; sub %y, (xor %x, -1)
; Transform it to:
; add (add %x, 1), %y
; We prefer this form because that is what -passes=reassociate would produce.
;------------------------------------------------------------------------------;
; Scalar tests
;------------------------------------------------------------------------------;
define i32 @p0_scalar(i32 %x, i32 %y) {
; CHECK-LABEL: @p0_scalar(
; CHECK-NEXT: [[T0_NEG:%.*]] = add i32 [[X:%.*]], 1
; CHECK-NEXT: [[T1:%.*]] = add i32 [[T0_NEG]], [[Y:%.*]]
; CHECK-NEXT: ret i32 [[T1]]
;
%t0 = xor i32 %x, -1
%t1 = sub i32 %y, %t0
ret i32 %t1
}
define i8 @p0_scalar_not_truly_negatable(i8 %x, i8 %y) {
; CHECK-LABEL: @p0_scalar_not_truly_negatable(
; CHECK-NEXT: [[XX:%.*]] = xor i8 [[X:%.*]], 123
; CHECK-NEXT: [[YY:%.*]] = xor i8 [[Y:%.*]], 45
; CHECK-NEXT: [[R:%.*]] = sub i8 [[XX]], [[YY]]
; CHECK-NEXT: ret i8 [[R]]
;
%xx = xor i8 %x, 123
%yy = xor i8 %y, 45
%r = sub i8 %xx, %yy
ret i8 %r
}
;------------------------------------------------------------------------------;
; Vector tests
;------------------------------------------------------------------------------;
define <4 x i32> @p1_vector_splat(<4 x i32> %x, <4 x i32> %y) {
; CHECK-LABEL: @p1_vector_splat(
; CHECK-NEXT: [[T0_NEG:%.*]] = add <4 x i32> [[X:%.*]], <i32 1, i32 1, i32 1, i32 1>
; CHECK-NEXT: [[T1:%.*]] = add <4 x i32> [[T0_NEG]], [[Y:%.*]]
; CHECK-NEXT: ret <4 x i32> [[T1]]
;
%t0 = xor <4 x i32> %x, <i32 -1, i32 -1, i32 -1, i32 -1>
%t1 = sub <4 x i32> %y, %t0
ret <4 x i32> %t1
}
define <4 x i32> @p2_vector_poison(<4 x i32> %x, <4 x i32> %y) {
; CHECK-LABEL: @p2_vector_poison(
; CHECK-NEXT: [[T0_NEG:%.*]] = add <4 x i32> [[X:%.*]], <i32 1, i32 1, i32 1, i32 1>
; CHECK-NEXT: [[T1:%.*]] = add <4 x i32> [[T0_NEG]], [[Y:%.*]]
; CHECK-NEXT: ret <4 x i32> [[T1]]
;
%t0 = xor <4 x i32> %x, <i32 -1, i32 -1, i32 poison, i32 -1>
%t1 = sub <4 x i32> %y, %t0
ret <4 x i32> %t1
}
;------------------------------------------------------------------------------;
; One-use test
;------------------------------------------------------------------------------;
declare void @use32(i32)
define i32 @p3_oneuse(i32 %x, i32 %y) {
; CHECK-LABEL: @p3_oneuse(
; CHECK-NEXT: [[T0:%.*]] = xor i32 [[X:%.*]], -1
; CHECK-NEXT: call void @use32(i32 [[T0]])
; CHECK-NEXT: [[T1:%.*]] = sub i32 [[Y:%.*]], [[T0]]
; CHECK-NEXT: ret i32 [[T1]]
;
%t0 = xor i32 %x, -1
call void @use32(i32 %t0)
%t1 = sub i32 %y, %t0
ret i32 %t1
}
;------------------------------------------------------------------------------;
; Basic negative tests
;------------------------------------------------------------------------------;
; The `sub` (and the fold) is not commutative.
define i32 @n4(i32 %x, i32 %y) {
; CHECK-LABEL: @n4(
; CHECK-NEXT: [[T0:%.*]] = xor i32 [[X:%.*]], -1
; CHECK-NEXT: [[T1:%.*]] = sub i32 [[T0]], [[Y:%.*]]
; CHECK-NEXT: ret i32 [[T1]]
;
%t0 = xor i32 %x, -1
%t1 = sub i32 %t0, %y ; swapped
ret i32 %t1
}
define i32 @n5_is_not_not(i32 %x, i32 %y) {
; CHECK-LABEL: @n5_is_not_not(
; CHECK-NEXT: [[T0:%.*]] = xor i32 [[X:%.*]], 2147483647
; CHECK-NEXT: [[T1:%.*]] = sub i32 [[Y:%.*]], [[T0]]
; CHECK-NEXT: ret i32 [[T1]]
;
%t0 = xor i32 %x, 2147483647 ; not -1
%t1 = sub i32 %y, %t0
ret i32 %t1
}
define <2 x i32> @n5_is_not_not_vec_splat(<2 x i32> %x, <2 x i32> %y) {
; CHECK-LABEL: @n5_is_not_not_vec_splat(
; CHECK-NEXT: [[T0:%.*]] = xor <2 x i32> [[X:%.*]], <i32 2147483647, i32 2147483647>
; CHECK-NEXT: [[T1:%.*]] = sub <2 x i32> [[Y:%.*]], [[T0]]
; CHECK-NEXT: ret <2 x i32> [[T1]]
;
%t0 = xor <2 x i32> %x, <i32 2147483647, i32 2147483647> ; signmask, but not -1
%t1 = sub <2 x i32> %y, %t0
ret <2 x i32> %t1
}
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