Iris Shi 32f911f3e8
[InstCombine] Fold ceil(X / (2 ^ C)) == 0 -> X == 0 (#143683)
Co-authored-by: Yingwei Zheng <dtcxzyw2333@gmail.com>
2025-06-23 10:51:17 +08:00

309 lines
10 KiB
LLVM

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
; RUN: opt < %s -passes=instcombine -S | FileCheck %s
define i1 @ceil_shift4(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift4(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i32 [[ARG0]], 0
; CHECK-NEXT: ret i1 [[TMP1]]
;
%quot = lshr i32 %arg0, 4
%rem = and i32 %arg0, 15
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_or_rem = or i32 %quot, %zext_has_rem
%is_zero = icmp eq i32 %quot_or_rem, 0
ret i1 %is_zero
}
define i1 @ceil_shift4_add(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift4_add(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP6:%.*]] = icmp eq i32 [[ARG0]], 0
; CHECK-NEXT: ret i1 [[TMP6]]
;
%quot = lshr i32 %arg0, 4
%rem = and i32 %arg0, 15
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%ceil = add i32 %quot, %zext_has_rem
%res = icmp eq i32 %ceil, 0
ret i1 %res
}
define i1 @ceil_shift6(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift6(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i32 [[ARG0]], 0
; CHECK-NEXT: ret i1 [[TMP1]]
;
%quot = lshr i32 %arg0, 6
%rem = and i32 %arg0, 63
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_or_rem = or i32 %quot, %zext_has_rem
%res = icmp eq i32 %quot_or_rem, 0
ret i1 %res
}
define i1 @ceil_shift6_ne(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift6_ne(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[RES:%.*]] = icmp ne i32 [[ARG0]], 0
; CHECK-NEXT: ret i1 [[RES]]
;
%quot = lshr i32 %arg0, 6
%rem = and i32 %arg0, 63
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_or_rem = or i32 %quot, %zext_has_rem
%res = icmp ne i32 %quot_or_rem, 0
ret i1 %res
}
define i1 @ceil_shift11(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift11(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i32 [[ARG0]], 0
; CHECK-NEXT: ret i1 [[TMP1]]
;
%quot = lshr i32 %arg0, 11
%rem = and i32 %arg0, 2047
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_or_rem = or i32 %quot, %zext_has_rem
%res = icmp eq i32 %quot_or_rem, 0
ret i1 %res
}
define i1 @ceil_shift11_ne(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift11_ne(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[RES:%.*]] = icmp ne i32 [[ARG0]], 0
; CHECK-NEXT: ret i1 [[RES]]
;
%quot = lshr i32 %arg0, 6
%rem = and i32 %arg0, 63
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_or_rem = or i32 %quot, %zext_has_rem
%res = icmp ne i32 %quot_or_rem, 0
ret i1 %res
}
define i1 @ceil_shift0(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift0(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i32 [[ARG0]], 0
; CHECK-NEXT: ret i1 [[TMP1]]
;
%quot = lshr i32 %arg0, 0
%rem = and i32 %arg0, 0
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_or_rem = or i32 %quot, %zext_has_rem
%res = icmp eq i32 %quot_or_rem, 0
ret i1 %res
}
define i1 @ceil_shift4_comm(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift4_comm(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP6:%.*]] = icmp eq i32 [[ARG0]], 0
; CHECK-NEXT: ret i1 [[TMP6]]
;
%quot = lshr i32 %arg0, 4
%rem = and i32 %arg0, 15
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_or_rem = or i32 %zext_has_rem, %quot
%res = icmp eq i32 %quot_or_rem, 0
ret i1 %res
}
declare void @use(i32)
define i1 @ceil_shift4_used_1(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift4_used_1(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 [[ARG0]], 4
; CHECK-NEXT: call void @use(i32 [[TMP1]])
; CHECK-NEXT: [[TMP6:%.*]] = icmp eq i32 [[ARG0]], 0
; CHECK-NEXT: ret i1 [[TMP6]]
;
%quot = lshr i32 %arg0, 4
call void @use(i32 %quot)
%rem = and i32 %arg0, 15
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_or_rem = or i32 %quot, %zext_has_rem
%res = icmp eq i32 %quot_or_rem, 0
ret i1 %res
}
define i1 @ceil_shift4_used_5(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift4_used_5(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 [[ARG0]], 4
; CHECK-NEXT: [[TMP2:%.*]] = and i32 [[ARG0]], 15
; CHECK-NEXT: [[TMP3:%.*]] = icmp ne i32 [[TMP2]], 0
; CHECK-NEXT: [[TMP4:%.*]] = zext i1 [[TMP3]] to i32
; CHECK-NEXT: [[TMP5:%.*]] = or i32 [[TMP1]], [[TMP4]]
; CHECK-NEXT: call void @use(i32 [[TMP5]])
; CHECK-NEXT: [[TMP6:%.*]] = icmp eq i32 [[ARG0]], 0
; CHECK-NEXT: ret i1 [[TMP6]]
;
%quot = lshr i32 %arg0, 4
%rem = and i32 %arg0, 15
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_or_rem = or i32 %quot, %zext_has_rem
call void @use(i32 %quot_or_rem)
%res = icmp eq i32 %quot_or_rem, 0
ret i1 %res
}
define i1 @ceil_shift4_used_add_nuw_nsw(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift4_used_add_nuw_nsw(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[QUOT:%.*]] = lshr i32 [[ARG0]], 4
; CHECK-NEXT: [[REM:%.*]] = and i32 [[ARG0]], 15
; CHECK-NEXT: [[HAS_REM:%.*]] = icmp ne i32 [[REM]], 0
; CHECK-NEXT: [[ZEXT_HAS_REM:%.*]] = zext i1 [[HAS_REM]] to i32
; CHECK-NEXT: [[CEIL:%.*]] = add nuw nsw i32 [[QUOT]], [[ZEXT_HAS_REM]]
; CHECK-NEXT: call void @use(i32 [[CEIL]])
; CHECK-NEXT: [[RES:%.*]] = icmp eq i32 [[ARG0]], 0
; CHECK-NEXT: ret i1 [[RES]]
;
%quot = lshr i32 %arg0, 4
%rem = and i32 %arg0, 15
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%ceil = add nuw nsw i32 %quot, %zext_has_rem
call void @use(i32 %ceil)
%res = icmp eq i32 %ceil, 0
ret i1 %res
}
define <4 x i1> @ceil_shift4_v4i32(<4 x i32> %arg0) {
; CHECK-LABEL: define <4 x i1> @ceil_shift4_v4i32(
; CHECK-SAME: <4 x i32> [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP1:%.*]] = icmp eq <4 x i32> [[ARG0]], zeroinitializer
; CHECK-NEXT: ret <4 x i1> [[TMP1]]
;
%quot = lshr <4 x i32> %arg0, splat (i32 16)
%rem = and <4 x i32> %arg0, splat (i32 65535)
%has_rem = icmp ne <4 x i32> %rem, zeroinitializer
%zext_has_rem = zext <4 x i1> %has_rem to <4 x i32>
%quot_or_rem = or <4 x i32> %quot, %zext_has_rem
%res = icmp eq <4 x i32> %quot_or_rem, zeroinitializer
ret <4 x i1> %res
}
define <8 x i1> @ceil_shift4_v8i16(<8 x i16> %arg0) {
; CHECK-LABEL: define <8 x i1> @ceil_shift4_v8i16(
; CHECK-SAME: <8 x i16> [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP1:%.*]] = icmp eq <8 x i16> [[ARG0]], zeroinitializer
; CHECK-NEXT: ret <8 x i1> [[TMP1]]
;
%quot = lshr <8 x i16> %arg0, splat (i16 4)
%rem = and <8 x i16> %arg0, splat (i16 15)
%has_rem = icmp ne <8 x i16> %rem, zeroinitializer
%zext_has_rem = zext <8 x i1> %has_rem to <8 x i16>
%quot_or_rem = or <8 x i16> %quot, %zext_has_rem
%res = icmp eq <8 x i16> %quot_or_rem, zeroinitializer
ret <8 x i1> %res
}
; negative tests
define i1 @ceil_shift_not_mask_1(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift_not_mask_1(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 [[ARG0]], 4
; CHECK-NEXT: [[TMP2:%.*]] = and i32 [[ARG0]], 31
; CHECK-NEXT: [[TMP3:%.*]] = icmp ne i32 [[TMP2]], 0
; CHECK-NEXT: [[TMP4:%.*]] = zext i1 [[TMP3]] to i32
; CHECK-NEXT: [[TMP5:%.*]] = or i32 [[TMP1]], [[TMP4]]
; CHECK-NEXT: [[TMP6:%.*]] = icmp eq i32 [[TMP5]], 0
; CHECK-NEXT: ret i1 [[TMP6]]
;
%quot = lshr i32 %arg0, 4
%rem = and i32 %arg0, 31
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_or_rem = or i32 %quot, %zext_has_rem
%res = icmp eq i32 %quot_or_rem, 0
ret i1 %res
}
define i1 @ceil_shift_not_mask_2(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift_not_mask_2(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 [[ARG0]], 5
; CHECK-NEXT: [[TMP2:%.*]] = and i32 [[ARG0]], 15
; CHECK-NEXT: [[TMP3:%.*]] = icmp ne i32 [[TMP2]], 0
; CHECK-NEXT: [[TMP4:%.*]] = zext i1 [[TMP3]] to i32
; CHECK-NEXT: [[TMP5:%.*]] = or i32 [[TMP1]], [[TMP4]]
; CHECK-NEXT: [[TMP6:%.*]] = icmp eq i32 [[TMP5]], 0
; CHECK-NEXT: ret i1 [[TMP6]]
;
%quot = lshr i32 %arg0, 5
%rem = and i32 %arg0, 15
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_or_rem = or i32 %quot, %zext_has_rem
%res = icmp eq i32 %quot_or_rem, 0
ret i1 %res
}
define i1 @ceil_shift_not_add_or(i32 %arg0) {
; CHECK-LABEL: define i1 @ceil_shift_not_add_or(
; CHECK-SAME: i32 [[ARG0:%.*]]) {
; CHECK-NEXT: [[REM:%.*]] = and i32 [[ARG0]], 15
; CHECK-NEXT: [[HAS_REM_NOT:%.*]] = icmp eq i32 [[REM]], 0
; CHECK-NEXT: [[TMP1:%.*]] = and i32 [[ARG0]], 32
; CHECK-NEXT: [[RES1:%.*]] = icmp eq i32 [[TMP1]], 0
; CHECK-NEXT: [[RES:%.*]] = or i1 [[HAS_REM_NOT]], [[RES1]]
; CHECK-NEXT: ret i1 [[RES]]
;
%quot = lshr i32 %arg0, 5
%rem = and i32 %arg0, 15
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%quot_and_rem = and i32 %quot, %zext_has_rem
%res = icmp eq i32 %quot_and_rem, 0
ret i1 %res
}
define i32 @ceil_shift_should_infer_ge_zero(i32 %x) {
; CHECK-LABEL: define i32 @ceil_shift_should_infer_ge_zero(
; CHECK-SAME: i32 [[X:%.*]]) {
; CHECK-NEXT: [[COND_NOT:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT: br i1 [[COND_NOT]], label %[[IF_ELSE:.*]], label %[[IF_THEN:.*]]
; CHECK: [[IF_THEN]]:
; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 [[X]], 20
; CHECK-NEXT: [[TMP2:%.*]] = and i32 [[X]], 1048575
; CHECK-NEXT: [[TMP3:%.*]] = icmp ne i32 [[TMP2]], 0
; CHECK-NEXT: [[TMP4:%.*]] = zext i1 [[TMP3]] to i32
; CHECK-NEXT: [[TMP5:%.*]] = add nuw nsw i32 [[TMP1]], [[TMP4]]
; CHECK-NEXT: ret i32 [[TMP5]]
; CHECK: [[IF_ELSE]]:
; CHECK-NEXT: ret i32 0
;
%cond = icmp ne i32 %x, 0
br i1 %cond, label %if.then, label %if.else
if.then:
%quot = lshr i32 %x, 20
%rem = and i32 %x, 1048575
%has_rem = icmp ne i32 %rem, 0
%zext_has_rem = zext i1 %has_rem to i32
%ceil = add nuw nsw i32 %quot, %zext_has_rem
%max = call i32 @llvm.umax.i32(i32 %ceil, i32 1)
ret i32 %max
if.else:
ret i32 0
}