; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -S -passes=instcombine | FileCheck %s ; ; Canonicalize ((X & -X) - 1) --> ((X - 1) & ~X) ; define i32 @dec_mask_neg_i32(i32 %X) { ; CHECK-LABEL: @dec_mask_neg_i32( ; CHECK-NEXT: [[TMP1:%.*]] = add i32 [[X:%.*]], -1 ; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[X]], -1 ; CHECK-NEXT: [[DEC:%.*]] = and i32 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i32 [[DEC]] ; %neg = sub i32 0, %X %mask = and i32 %neg, %X %dec = add i32 %mask, -1 ret i32 %dec } define i32 @dec_mask_commute_neg_i32(i32 %A) { ; CHECK-LABEL: @dec_mask_commute_neg_i32( ; CHECK-NEXT: [[X:%.*]] = sdiv i32 42, [[A:%.*]] ; CHECK-NEXT: [[TMP1:%.*]] = add nsw i32 [[X]], -1 ; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[X]], -1 ; CHECK-NEXT: [[DEC:%.*]] = and i32 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i32 [[DEC]] ; %X = sdiv i32 42, %A ; thwart complexity-based canonicalization %neg = sub i32 0, %X %mask = and i32 %X, %neg %dec = add i32 %mask, -1 ret i32 %dec } define i32 @dec_commute_mask_neg_i32(i32 %X) { ; CHECK-LABEL: @dec_commute_mask_neg_i32( ; CHECK-NEXT: [[TMP1:%.*]] = add i32 [[X:%.*]], -1 ; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[X]], -1 ; CHECK-NEXT: [[DEC:%.*]] = and i32 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i32 [[DEC]] ; %neg = sub i32 0, %X %mask = and i32 %neg, %X %dec = add i32 -1, %mask ret i32 %dec } define i32 @dec_mask_neg_multiuse_i32(i32 %X) { ; CHECK-LABEL: @dec_mask_neg_multiuse_i32( ; CHECK-NEXT: [[NEG:%.*]] = sub i32 0, [[X:%.*]] ; CHECK-NEXT: [[MASK:%.*]] = and i32 [[NEG]], [[X]] ; CHECK-NEXT: [[DEC:%.*]] = add i32 [[MASK]], -1 ; CHECK-NEXT: call void @use(i32 [[NEG]]) ; CHECK-NEXT: ret i32 [[DEC]] ; %neg = sub i32 0, %X %mask = and i32 %neg, %X %dec = add i32 %mask, -1 call void @use(i32 %neg) ret i32 %dec } define i32 @dec_mask_multiuse_neg_i32(i32 %X) { ; CHECK-LABEL: @dec_mask_multiuse_neg_i32( ; CHECK-NEXT: [[NEG:%.*]] = sub i32 0, [[X:%.*]] ; CHECK-NEXT: [[MASK:%.*]] = and i32 [[NEG]], [[X]] ; CHECK-NEXT: [[DEC:%.*]] = add i32 [[MASK]], -1 ; CHECK-NEXT: call void @use(i32 [[MASK]]) ; CHECK-NEXT: ret i32 [[DEC]] ; %neg = sub i32 0, %X %mask = and i32 %neg, %X %dec = add i32 %mask, -1 call void @use(i32 %mask) ret i32 %dec } define <2 x i32> @dec_mask_neg_v2i32(<2 x i32> %X) { ; CHECK-LABEL: @dec_mask_neg_v2i32( ; CHECK-NEXT: [[TMP1:%.*]] = add <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[TMP2:%.*]] = xor <2 x i32> [[X]], ; CHECK-NEXT: [[DEC:%.*]] = and <2 x i32> [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret <2 x i32> [[DEC]] ; %neg = sub <2 x i32> zeroinitializer, %X %mask = and <2 x i32> %neg, %X %dec = add <2 x i32> %mask, ret <2 x i32> %dec } define <2 x i32> @dec_mask_neg_v2i32_undef(<2 x i32> %X) { ; CHECK-LABEL: @dec_mask_neg_v2i32_undef( ; CHECK-NEXT: [[TMP1:%.*]] = add <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[TMP2:%.*]] = xor <2 x i32> [[X]], ; CHECK-NEXT: [[DEC:%.*]] = and <2 x i32> [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret <2 x i32> [[DEC]] ; %neg = sub <2 x i32> zeroinitializer, %X %mask = and <2 x i32> %neg, %X %dec = add <2 x i32> %mask, ret <2 x i32> %dec } define <2 x i32> @dec_mask_multiuse_neg_multiuse_v2i32(<2 x i32> %X) { ; CHECK-LABEL: @dec_mask_multiuse_neg_multiuse_v2i32( ; CHECK-NEXT: [[NEG:%.*]] = sub <2 x i32> zeroinitializer, [[X:%.*]] ; CHECK-NEXT: [[MASK:%.*]] = and <2 x i32> [[NEG]], [[X]] ; CHECK-NEXT: [[DEC:%.*]] = add <2 x i32> [[MASK]], ; CHECK-NEXT: call void @usev(<2 x i32> [[NEG]]) ; CHECK-NEXT: call void @usev(<2 x i32> [[MASK]]) ; CHECK-NEXT: ret <2 x i32> [[DEC]] ; %neg = sub <2 x i32> zeroinitializer, %X %mask = and <2 x i32> %neg, %X %dec = add <2 x i32> %mask, call void @usev(<2 x i32> %neg) call void @usev(<2 x i32> %mask) ret <2 x i32> %dec } declare void @use(i32) declare void @usev(<2 x i32>)