| ; 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 |
| } |