; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=instcombine -S | FileCheck %s
; https://bugs.llvm.org/show_bug.cgi?id=38123
; Pattern:
; x & C == x
; Should be transformed into:
; x u<= C
; Iff: isPowerOf2(C + 1)
; C can be 0 and -1.
; ============================================================================ ;
; Basic positive tests
; ============================================================================ ;
define i1 @p0(i8 %x) {
; CHECK-LABEL: @p0(
; CHECK-NEXT: [[RET:%.*]] = icmp ult i8 [[X:%.*]], 4
; CHECK-NEXT: ret i1 [[RET]]
;
%tmp0 = and i8 %x, 3
%ret = icmp eq i8 %tmp0, %x
ret i1 %ret
}
define i1 @pv(i8 %x, i8 %y) {
; CHECK-LABEL: @pv(
; CHECK-NEXT: [[TMP0:%.*]] = lshr i8 -1, [[Y:%.*]]
; CHECK-NEXT: [[RET:%.*]] = icmp ule i8 [[X:%.*]], [[TMP0]]
; CHECK-NEXT: ret i1 [[RET]]
;
%tmp0 = lshr i8 -1, %y
%tmp1 = and i8 %tmp0, %x
%ret = icmp eq i8 %tmp1, %x
ret i1 %ret
}
; ============================================================================ ;
; Vector tests
; ============================================================================ ;
define <2 x i1> @p1_vec_splat(<2 x i8> %x) {
; CHECK-LABEL: @p1_vec_splat(
; CHECK-NEXT: [[RET:%.*]] = icmp ult <2 x i8> [[X:%.*]], <i8 4, i8 4>
; CHECK-NEXT: ret <2 x i1> [[RET]]
;
%tmp0 = and <2 x i8> %x, <i8 3, i8 3>
%ret = icmp eq <2 x i8> %tmp0, %x
ret <2 x i1> %ret
}
define <2 x i1> @p2_vec_nonsplat(<2 x i8> %x) {
; CHECK-LABEL: @p2_vec_nonsplat(
; CHECK-NEXT: [[RET:%.*]] = icmp ult <2 x i8> [[X:%.*]], <i8 4, i8 16>
; CHECK-NEXT: ret <2 x i1> [[RET]]
;
%tmp0 = and <2 x i8> %x, <i8 3, i8 15> ; doesn't have to be splat.
%ret = icmp eq <2 x i8> %tmp0, %x
ret <2 x i1> %ret
}
define <2 x i1> @p2_vec_nonsplat_edgecase0(<2 x i8> %x) {
; CHECK-LABEL: @p2_vec_nonsplat_edgecase0(
; CHECK-NEXT: [[RET:%.*]] = icmp ult <2 x i8> [[X:%.*]], <i8 4, i8 1>
; CHECK-NEXT: ret <2 x i1> [[RET]]
;
%tmp0 = and <2 x i8> %x, <i8 3, i8 0>
%ret = icmp eq <2 x i8> %tmp0, %x
ret <2 x i1> %ret
}
define <2 x i1> @p2_vec_nonsplat_edgecase1(<2 x i8> %x) {
; CHECK-LABEL: @p2_vec_nonsplat_edgecase1(
; CHECK-NEXT: [[RET:%.*]] = icmp ule <2 x i8> [[X:%.*]], <i8 3, i8 -1>
; CHECK-NEXT: ret <2 x i1> [[RET]]
;
%tmp0 = and <2 x i8> %x, <i8 3, i8 -1>
%ret = icmp eq <2 x i8> %tmp0, %x
ret <2 x i1> %ret
}
define <3 x i1> @p3_vec_splat_poison(<3 x i8> %x) {
; CHECK-LABEL: @p3_vec_splat_poison(
; CHECK-NEXT: [[RET:%.*]] = icmp ult <3 x i8> [[X:%.*]], <i8 4, i8 4, i8 4>
; CHECK-NEXT: ret <3 x i1> [[RET]]
;
%tmp0 = and <3 x i8> %x, <i8 3, i8 poison, i8 3>
%ret = icmp eq <3 x i8> %tmp0, %x
ret <3 x i1> %ret
}
; ============================================================================ ;
; Commutativity tests.
; ============================================================================ ;
declare i8 @gen8()
define i1 @c0() {
; CHECK-LABEL: @c0(
; CHECK-NEXT: [[X:%.*]] = call i8 @gen8()
; CHECK-NEXT: [[RET:%.*]] = icmp ult i8 [[X]], 4
; CHECK-NEXT: ret i1 [[RET]]
;
%x = call i8 @gen8()
%tmp0 = and i8 %x, 3
%ret = icmp eq i8 %x, %tmp0 ; swapped order
ret i1 %ret
}
; ============================================================================ ;
; Commutativity tests with variable
; ============================================================================ ;
define i1 @cv0(i8 %y) {
; CHECK-LABEL: @cv0(
; CHECK-NEXT: [[X:%.*]] = call i8 @gen8()
; CHECK-NEXT: [[TMP0:%.*]] = lshr i8 -1, [[Y:%.*]]
; CHECK-NEXT: [[RET:%.*]] = icmp ule i8 [[X]], [[TMP0]]
; CHECK-NEXT: ret i1 [[RET]]
;
%x = call i8 @gen8()
%tmp0 = lshr i8 -1, %y
%tmp1 = and i8 %x, %tmp0 ; swapped order
%ret = icmp eq i8 %tmp1, %x
ret i1 %ret
}
define i1 @cv1(i8 %y) {
; CHECK-LABEL: @cv1(
; CHECK-NEXT: [[X:%.*]] = call i8 @gen8()
; CHECK-NEXT: [[TMP0:%.*]] = lshr i8 -1, [[Y:%.*]]
; CHECK-NEXT: [[RET:%.*]] = icmp ule i8 [[X]], [[TMP0]]
; CHECK-NEXT: ret i1 [[RET]]
;
%x = call i8 @gen8()
%tmp0 = lshr i8 -1, %y
%tmp1 = and i8 %tmp0, %x
%ret = icmp eq i8 %x, %tmp1 ; swapped order
ret i1 %ret
}
define i1 @cv2(i8 %y) {
; CHECK-LABEL: @cv2(
; CHECK-NEXT: [[X:%.*]] = call i8 @gen8()
; CHECK-NEXT: [[TMP0:%.*]] = lshr i8 -1, [[Y:%.*]]
; CHECK-NEXT: [[RET:%.*]] = icmp ule i8 [[X]], [[TMP0]]
; CHECK-NEXT: ret i1 [[RET]]
;
%x = call i8 @gen8()
%tmp0 = lshr i8 -1, %y
%tmp1 = and i8 %x, %tmp0 ; swapped order
%ret = icmp eq i8 %x, %tmp1 ; swapped order
ret i1 %ret
}
; ============================================================================ ;
; One-use tests. We don't care about multi-uses here.
; ============================================================================ ;
declare void @use8(i8)
define i1 @oneuse0(i8 %x) {
; CHECK-LABEL: @oneuse0(
; CHECK-NEXT: [[TMP0:%.*]] = and i8 [[X:%.*]], 3
; CHECK-NEXT: call void @use8(i8 [[TMP0]])
; CHECK-NEXT: [[RET:%.*]] = icmp ult i8 [[X]], 4
; CHECK-NEXT: ret i1 [[RET]]
;
%tmp0 = and i8 %x, 3
call void @use8(i8 %tmp0)
%ret = icmp eq i8 %tmp0, %x
ret i1 %ret
}
; ============================================================================ ;
; Negative tests
; ============================================================================ ;
define i1 @n0(i8 %x) {
; CHECK-LABEL: @n0(
; CHECK-NEXT: [[TMP1:%.*]] = and i8 [[X:%.*]], -5
; CHECK-NEXT: [[RET:%.*]] = icmp eq i8 [[TMP1]], 0
; CHECK-NEXT: ret i1 [[RET]]
;
%tmp0 = and i8 %x, 4 ; power-of-two, but invalid.
%ret = icmp eq i8 %tmp0, %x
ret i1 %ret
}
define i1 @n1(i8 %x, i8 %y, i8 %notx) {
; CHECK-LABEL: @n1(
; CHECK-NEXT: [[TMP0:%.*]] = and i8 [[X:%.*]], 3
; CHECK-NEXT: [[RET:%.*]] = icmp eq i8 [[TMP0]], [[NOTX:%.*]]
; CHECK-NEXT: ret i1 [[RET]]
;
%tmp0 = and i8 %x, 3
%ret = icmp eq i8 %tmp0, %notx ; not %x
ret i1 %ret
}
define <2 x i1> @n2(<2 x i8> %x) {
; CHECK-LABEL: @n2(
; CHECK-NEXT: [[TMP1:%.*]] = and <2 x i8> [[X:%.*]], <i8 -4, i8 -17>
; CHECK-NEXT: [[RET:%.*]] = icmp eq <2 x i8> [[TMP1]], zeroinitializer
; CHECK-NEXT: ret <2 x i1> [[RET]]
;
%tmp0 = and <2 x i8> %x, <i8 3, i8 16> ; only the first one is valid.
%ret = icmp eq <2 x i8> %tmp0, %x
ret <2 x i1> %ret
}
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