; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -passes=instcombine -S | FileCheck %s ; Transform ; (~x) a>> y ; into: ; ~(x a>> y) declare void @use8(i8) ; Most basic positive test define i8 @t0(i8 %x, i8 %y) { ; CHECK-LABEL: @t0( ; CHECK-NEXT: [[NOT_X_NOT:%.*]] = ashr i8 [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[ASHR:%.*]] = xor i8 [[NOT_X_NOT]], -1 ; CHECK-NEXT: ret i8 [[ASHR]] ; %not_x = xor i8 %x, -1 %ashr = ashr i8 %not_x, %y ret i8 %ashr } ; 'exact'-ness isn't preserved! define i8 @t1(i8 %x, i8 %y) { ; CHECK-LABEL: @t1( ; CHECK-NEXT: [[NOT_X_NOT:%.*]] = ashr i8 [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[ASHR:%.*]] = xor i8 [[NOT_X_NOT]], -1 ; CHECK-NEXT: ret i8 [[ASHR]] ; %not_x = xor i8 %x, -1 %ashr = ashr exact i8 %not_x, %y ret i8 %ashr } ; Basic vector test define <2 x i8> @t2_vec(<2 x i8> %x, <2 x i8> %y) { ; CHECK-LABEL: @t2_vec( ; CHECK-NEXT: [[NOT_X_NOT:%.*]] = ashr <2 x i8> [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[ASHR:%.*]] = xor <2 x i8> [[NOT_X_NOT]], <i8 -1, i8 -1> ; CHECK-NEXT: ret <2 x i8> [[ASHR]] ; %not_x = xor <2 x i8> %x, <i8 -1, i8 -1> %ashr = ashr <2 x i8> %not_x, %y ret <2 x i8> %ashr } ; Note that we must sanitize undef elts of -1 constant to -1 or 0. define <2 x i8> @t3_vec_undef(<2 x i8> %x, <2 x i8> %y) { ; CHECK-LABEL: @t3_vec_undef( ; CHECK-NEXT: [[NOT_X_NOT:%.*]] = ashr <2 x i8> [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[ASHR:%.*]] = xor <2 x i8> [[NOT_X_NOT]], <i8 -1, i8 -1> ; CHECK-NEXT: ret <2 x i8> [[ASHR]] ; %not_x = xor <2 x i8> %x, <i8 -1, i8 undef> %ashr = ashr <2 x i8> %not_x, %y ret <2 x i8> %ashr } ; Extra use prevents the fold. define i8 @n4(i8 %x, i8 %y) { ; CHECK-LABEL: @n4( ; CHECK-NEXT: [[NOT_X:%.*]] = xor i8 [[X:%.*]], -1 ; CHECK-NEXT: call void @use8(i8 [[NOT_X]]) ; CHECK-NEXT: [[ASHR:%.*]] = ashr i8 [[NOT_X]], [[Y:%.*]] ; CHECK-NEXT: ret i8 [[ASHR]] ; %not_x = xor i8 %x, -1 call void @use8(i8 %not_x) %ashr = ashr i8 %not_x, %y ret i8 %ashr }