; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt -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: [[TMP1:%.*]] = icmp slt i32 [[X:%.*]], 255 ; CHECK-NEXT: [[OR:%.*]] = select i1 [[TMP1]], 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 } ; 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 } ; 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> , <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, %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> , <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, %or = or <4 x i32> %shr, %x ret <4 x i32> %or } 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> , <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, %or = or <4 x i32> %x, %shr ret <4 x i32> %or } ; Extra uses define i32 @sub_ashr_or_i32_extra_use_sub(i32 %x, i32 %y, i32* %p) { ; CHECK-LABEL: @sub_ashr_or_i32_extra_use_sub( ; CHECK-NEXT: [[SUB:%.*]] = sub nsw i32 [[Y:%.*]], [[X:%.*]] ; CHECK-NEXT: store i32 [[SUB]], i32* [[P:%.*]], align 4 ; 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 store i32 %sub, i32* %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, i32* %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]], i32* [[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, i32* %p ret i32 %or } ; Negative Tests define i32 @sub_ashr_or_i32_extra_use_ashr(i32 %x, i32 %y, i32* %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]], i32* [[P:%.*]], align 4 ; CHECK-NEXT: [[OR:%.*]] = or i32 [[SHR]], [[X]] ; CHECK-NEXT: ret i32 [[OR]] ; %sub = sub nsw i32 %y, %x %shr = ashr i32 %sub, 31 store i32 %shr, i32* %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 <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> , [[X:%.*]] ; CHECK-NEXT: [[SHR:%.*]] = ashr <4 x i32> [[SUB]], ; CHECK-NEXT: [[OR:%.*]] = or <4 x i32> [[SHR]], [[X]] ; CHECK-NEXT: ret <4 x i32> [[OR]] ; %sub = sub <4 x i32> , %x %shr = ashr <4 x i32> %sub, %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> , [[X:%.*]] ; CHECK-NEXT: [[SHR:%.*]] = ashr <4 x i32> [[SUB]], ; CHECK-NEXT: [[OR:%.*]] = or <4 x i32> [[SHR]], [[X]] ; CHECK-NEXT: ret <4 x i32> [[OR]] ; %sub = sub nsw <4 x i32> , %x %shr = ashr <4 x i32> %sub, %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 }