; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=instcombine %s -S -o - | FileCheck %s
; Clamp positive to allOnes:
; E.g., clamp255 implemented in a shifty way, could be optimized as v > 255 ? 255 : v, where sub hasNoSignedWrap.
; int32 clamp255(int32 v) {
; return (((255 - (v)) >> 31) | (v)) & 255;
; }
;
; Scalar Types
define i32 @clamp255_i32(i32 %x) {
; CHECK-LABEL: @clamp255_i32(
; CHECK-NEXT: [[OR:%.*]] = call i32 @llvm.smin.i32(i32 [[X:%.*]], i32 255)
; CHECK-NEXT: [[AND:%.*]] = and i32 [[OR]], 255
; CHECK-NEXT: ret i32 [[AND]]
;
%sub = sub nsw i32 255, %x
%shr = ashr i32 %sub, 31
%or = or i32 %shr, %x
%and = and i32 %or, 255
ret i32 %and
}
define i8 @sub_ashr_or_i8(i8 %x, i8 %y) {
; CHECK-LABEL: @sub_ashr_or_i8(
; CHECK-NEXT: [[TMP1:%.*]] = icmp slt i8 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[OR:%.*]] = select i1 [[TMP1]], i8 -1, i8 [[X]]
; CHECK-NEXT: ret i8 [[OR]]
;
%sub = sub nsw i8 %y, %x
%shr = ashr i8 %sub, 7
%or = or i8 %shr, %x
ret i8 %or
}
define i16 @sub_ashr_or_i16(i16 %x, i16 %y) {
; CHECK-LABEL: @sub_ashr_or_i16(
; CHECK-NEXT: [[TMP1:%.*]] = icmp slt i16 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[OR:%.*]] = select i1 [[TMP1]], i16 -1, i16 [[X]]
; CHECK-NEXT: ret i16 [[OR]]
;
%sub = sub nsw i16 %y, %x
%shr = ashr i16 %sub, 15
%or = or i16 %shr, %x
ret i16 %or
}
define i32 @sub_ashr_or_i32(i32 %x, i32 %y) {
; CHECK-LABEL: @sub_ashr_or_i32(
; CHECK-NEXT: [[TMP1:%.*]] = icmp slt i32 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[OR:%.*]] = select i1 [[TMP1]], i32 -1, i32 [[X]]
; CHECK-NEXT: ret i32 [[OR]]
;
%sub = sub nsw i32 %y, %x
%shr = ashr i32 %sub, 31
%or = or i32 %shr, %x
ret i32 %or
}
define i64 @sub_ashr_or_i64(i64 %x, i64 %y) {
; CHECK-LABEL: @sub_ashr_or_i64(
; CHECK-NEXT: [[TMP1:%.*]] = icmp slt i64 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[OR:%.*]] = select i1 [[TMP1]], i64 -1, i64 [[X]]
; CHECK-NEXT: ret i64 [[OR]]
;
%sub = sub nsw i64 %y, %x
%shr = ashr i64 %sub, 63
%or = or i64 %shr, %x
ret i64 %or
}
define i32 @neg_or_ashr_i32(i32 %x) {
; CHECK-LABEL: @neg_or_ashr_i32(
; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i32 [[X:%.*]], 0
; CHECK-NEXT: [[SHR:%.*]] = sext i1 [[TMP1]] to i32
; CHECK-NEXT: ret i32 [[SHR]]
;
%neg = sub i32 0, %x
%or = or i32 %neg, %x
%shr = ashr i32 %or, 31
ret i32 %shr
}
; nuw nsw
define i32 @sub_ashr_or_i32_nuw_nsw(i32 %x, i32 %y) {
; CHECK-LABEL: @sub_ashr_or_i32_nuw_nsw(
; CHECK-NEXT: [[TMP1:%.*]] = icmp slt i32 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[OR:%.*]] = select i1 [[TMP1]], i32 -1, i32 [[X]]
; CHECK-NEXT: ret i32 [[OR]]
;
%sub = sub nuw nsw i32 %y, %x
%shr = ashr i32 %sub, 31
%or = or i32 %shr, %x
ret i32 %or
}
; Commute
define i32 @sub_ashr_or_i32_commute(i32 %x, i32 %y) {
; CHECK-LABEL: @sub_ashr_or_i32_commute(
; CHECK-NEXT: [[TMP1:%.*]] = icmp slt i32 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[OR:%.*]] = select i1 [[TMP1]], i32 -1, i32 [[X]]
; CHECK-NEXT: ret i32 [[OR]]
;
%sub = sub nsw i32 %y, %x
%shr = ashr i32 %sub, 31
%or = or i32 %x, %shr ; commute %shr and %x
ret i32 %or
}
define i32 @neg_or_ashr_i32_commute(i32 %x0) {
; CHECK-LABEL: @neg_or_ashr_i32_commute(
; CHECK-NEXT: [[X:%.*]] = sdiv i32 42, [[X0:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i32 [[X]], 0
; CHECK-NEXT: [[SHR:%.*]] = sext i1 [[TMP1]] to i32
; CHECK-NEXT: ret i32 [[SHR]]
;
%x = sdiv i32 42, %x0 ; thwart complexity-based canonicalization
%neg = sub i32 0, %x
%or = or i32 %x, %neg
%shr = ashr i32 %or, 31
ret i32 %shr
}
; Vector Types
define <4 x i32> @sub_ashr_or_i32_vec(<4 x i32> %x, <4 x i32> %y) {
; CHECK-LABEL: @sub_ashr_or_i32_vec(
; CHECK-NEXT: [[TMP1:%.*]] = icmp slt <4 x i32> [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[OR:%.*]] = select <4 x i1> [[TMP1]], <4 x i32> <i32 -1, i32 -1, i32 -1, i32 -1>, <4 x i32> [[X]]
; CHECK-NEXT: ret <4 x i32> [[OR]]
;
%sub = sub nsw <4 x i32> %y, %x
%shr = ashr <4 x i32> %sub, <i32 31, i32 31, i32 31, i32 31>
%or = or <4 x i32> %shr, %x
ret <4 x i32> %or
}
define <4 x i32> @sub_ashr_or_i32_vec_nuw_nsw(<4 x i32> %x, <4 x i32> %y) {
; CHECK-LABEL: @sub_ashr_or_i32_vec_nuw_nsw(
; CHECK-NEXT: [[TMP1:%.*]] = icmp slt <4 x i32> [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[OR:%.*]] = select <4 x i1> [[TMP1]], <4 x i32> <i32 -1, i32 -1, i32 -1, i32 -1>, <4 x i32> [[X]]
; CHECK-NEXT: ret <4 x i32> [[OR]]
;
%sub = sub nuw nsw <4 x i32> %y, %x
%shr = ashr <4 x i32> %sub, <i32 31, i32 31, i32 31, i32 31>
%or = or <4 x i32> %shr, %x
ret <4 x i32> %or
}
define <4 x i32> @neg_or_ashr_i32_vec(<4 x i32> %x) {
; CHECK-LABEL: @neg_or_ashr_i32_vec(
; CHECK-NEXT: [[TMP1:%.*]] = icmp ne <4 x i32> [[X:%.*]], zeroinitializer
; CHECK-NEXT: [[SHR:%.*]] = sext <4 x i1> [[TMP1]] to <4 x i32>
; CHECK-NEXT: ret <4 x i32> [[SHR]]
;
%neg = sub <4 x i32> zeroinitializer, %x
%or = or <4 x i32> %neg, %x
%shr = ashr <4 x i32> %or, <i32 31, i32 31, i32 31, i32 31>
ret <4 x i32> %shr
}
define <4 x i32> @sub_ashr_or_i32_vec_commute(<4 x i32> %x, <4 x i32> %y) {
; CHECK-LABEL: @sub_ashr_or_i32_vec_commute(
; CHECK-NEXT: [[TMP1:%.*]] = icmp slt <4 x i32> [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[OR:%.*]] = select <4 x i1> [[TMP1]], <4 x i32> <i32 -1, i32 -1, i32 -1, i32 -1>, <4 x i32> [[X]]
; CHECK-NEXT: ret <4 x i32> [[OR]]
;
%sub = sub nsw <4 x i32> %y, %x
%shr = ashr <4 x i32> %sub, <i32 31, i32 31, i32 31, i32 31>
%or = or <4 x i32> %x, %shr
ret <4 x i32> %or
}
define <4 x i32> @neg_or_ashr_i32_vec_commute(<4 x i32> %x0) {
; CHECK-LABEL: @neg_or_ashr_i32_vec_commute(
; CHECK-NEXT: [[X:%.*]] = sdiv <4 x i32> <i32 42, i32 42, i32 42, i32 42>, [[X0:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = icmp ne <4 x i32> [[X]], zeroinitializer
; CHECK-NEXT: [[SHR:%.*]] = sext <4 x i1> [[TMP1]] to <4 x i32>
; CHECK-NEXT: ret <4 x i32> [[SHR]]
;
%x = sdiv <4 x i32> <i32 42, i32 42, i32 42, i32 42>, %x0 ; thwart complexity-based canonicalization
%neg = sub <4 x i32> zeroinitializer, %x
%or = or <4 x i32> %x, %neg
%shr = ashr <4 x i32> %or, <i32 31, i32 31, i32 31, i32 31>
ret <4 x i32> %shr
}
; Extra uses
define i32 @sub_ashr_or_i32_extra_use_sub(i32 %x, i32 %y, ptr %p) {
; CHECK-LABEL: @sub_ashr_or_i32_extra_use_sub(
; CHECK-NEXT: [[SUB:%.*]] = sub nsw i32 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: store i32 [[SUB]], ptr [[P:%.*]], align 4
; CHECK-NEXT: [[TMP1:%.*]] = icmp sgt i32 [[X]], [[Y]]
; CHECK-NEXT: [[OR:%.*]] = select i1 [[TMP1]], i32 -1, i32 [[X]]
; CHECK-NEXT: ret i32 [[OR]]
;
%sub = sub nsw i32 %y, %x
store i32 %sub, ptr %p
%shr = ashr i32 %sub, 31
%or = or i32 %shr, %x
ret i32 %or
}
define i32 @sub_ashr_or_i32_extra_use_or(i32 %x, i32 %y, ptr %p) {
; CHECK-LABEL: @sub_ashr_or_i32_extra_use_or(
; CHECK-NEXT: [[TMP1:%.*]] = icmp slt i32 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[OR:%.*]] = select i1 [[TMP1]], i32 -1, i32 [[X]]
; CHECK-NEXT: store i32 [[OR]], ptr [[P:%.*]], align 4
; CHECK-NEXT: ret i32 [[OR]]
;
%sub = sub nsw i32 %y, %x
%shr = ashr i32 %sub, 31
%or = or i32 %shr, %x
store i32 %or, ptr %p
ret i32 %or
}
define i32 @neg_extra_use_or_ashr_i32(i32 %x, ptr %p) {
; CHECK-LABEL: @neg_extra_use_or_ashr_i32(
; CHECK-NEXT: [[NEG:%.*]] = sub i32 0, [[X:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i32 [[X]], 0
; CHECK-NEXT: [[SHR:%.*]] = sext i1 [[TMP1]] to i32
; CHECK-NEXT: store i32 [[NEG]], ptr [[P:%.*]], align 4
; CHECK-NEXT: ret i32 [[SHR]]
;
%neg = sub i32 0, %x
%or = or i32 %neg, %x
%shr = ashr i32 %or, 31
store i32 %neg, ptr %p
ret i32 %shr
}
; Negative Tests
define i32 @sub_ashr_or_i32_extra_use_ashr(i32 %x, i32 %y, ptr %p) {
; CHECK-LABEL: @sub_ashr_or_i32_extra_use_ashr(
; CHECK-NEXT: [[TMP1:%.*]] = icmp slt i32 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[SHR:%.*]] = sext i1 [[TMP1]] to i32
; CHECK-NEXT: store i32 [[SHR]], ptr [[P:%.*]], align 4
; CHECK-NEXT: [[OR:%.*]] = or i32 [[X]], [[SHR]]
; CHECK-NEXT: ret i32 [[OR]]
;
%sub = sub nsw i32 %y, %x
%shr = ashr i32 %sub, 31
store i32 %shr, ptr %p
%or = or i32 %shr, %x
ret i32 %or
}
define i32 @sub_ashr_or_i32_no_nsw_nuw(i32 %x, i32 %y) {
; CHECK-LABEL: @sub_ashr_or_i32_no_nsw_nuw(
; CHECK-NEXT: [[SUB:%.*]] = sub i32 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[SHR:%.*]] = ashr i32 [[SUB]], 31
; CHECK-NEXT: [[OR:%.*]] = or i32 [[SHR]], [[X]]
; CHECK-NEXT: ret i32 [[OR]]
;
%sub = sub i32 %y, %x
%shr = ashr i32 %sub, 31
%or = or i32 %shr, %x
ret i32 %or
}
define i32 @neg_or_extra_use_ashr_i32(i32 %x, ptr %p) {
; CHECK-LABEL: @neg_or_extra_use_ashr_i32(
; CHECK-NEXT: [[NEG:%.*]] = sub i32 0, [[X:%.*]]
; CHECK-NEXT: [[OR:%.*]] = or i32 [[X]], [[NEG]]
; CHECK-NEXT: [[SHR:%.*]] = ashr i32 [[OR]], 31
; CHECK-NEXT: store i32 [[OR]], ptr [[P:%.*]], align 4
; CHECK-NEXT: ret i32 [[SHR]]
;
%neg = sub i32 0, %x
%or = or i32 %neg, %x
%shr = ashr i32 %or, 31
store i32 %or, ptr %p
ret i32 %shr
}
define <4 x i32> @sub_ashr_or_i32_vec_undef1(<4 x i32> %x) {
; CHECK-LABEL: @sub_ashr_or_i32_vec_undef1(
; CHECK-NEXT: [[SUB:%.*]] = sub <4 x i32> <i32 255, i32 255, i32 undef, i32 255>, [[X:%.*]]
; CHECK-NEXT: [[SHR:%.*]] = ashr <4 x i32> [[SUB]], <i32 31, i32 31, i32 31, i32 31>
; CHECK-NEXT: [[OR:%.*]] = or <4 x i32> [[SHR]], [[X]]
; CHECK-NEXT: ret <4 x i32> [[OR]]
;
%sub = sub <4 x i32> <i32 255, i32 255, i32 undef, i32 255>, %x
%shr = ashr <4 x i32> %sub, <i32 31, i32 31, i32 31, i32 31>
%or = or <4 x i32> %shr, %x
ret <4 x i32> %or
}
define <4 x i32> @sub_ashr_or_i32_vec_undef2(<4 x i32> %x) {
; CHECK-LABEL: @sub_ashr_or_i32_vec_undef2(
; CHECK-NEXT: [[SUB:%.*]] = sub nsw <4 x i32> <i32 255, i32 255, i32 255, i32 255>, [[X:%.*]]
; CHECK-NEXT: [[SHR:%.*]] = ashr <4 x i32> [[SUB]], <i32 undef, i32 31, i32 31, i32 31>
; CHECK-NEXT: [[OR:%.*]] = or <4 x i32> [[SHR]], [[X]]
; CHECK-NEXT: ret <4 x i32> [[OR]]
;
%sub = sub nsw <4 x i32> <i32 255, i32 255, i32 255, i32 255>, %x
%shr = ashr <4 x i32> %sub, <i32 undef, i32 31, i32 31, i32 31>
%or = or <4 x i32> %shr, %x
ret <4 x i32> %or
}
define i32 @sub_ashr_or_i32_shift_wrong_bit(i32 %x, i32 %y) {
; CHECK-LABEL: @sub_ashr_or_i32_shift_wrong_bit(
; CHECK-NEXT: [[SUB:%.*]] = sub nsw i32 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[SHR:%.*]] = ashr i32 [[SUB]], 11
; CHECK-NEXT: [[OR:%.*]] = or i32 [[SHR]], [[X]]
; CHECK-NEXT: ret i32 [[OR]]
;
%sub = sub nsw i32 %y, %x
%shr = ashr i32 %sub, 11
%or = or i32 %shr, %x
ret i32 %or
}
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