| ; RUN: opt < %s -instsimplify -S | FileCheck %s |
| |
| ; PR8862 |
| |
| ; CHECK: @shift1 |
| ; CHECK: ret i32 %A |
| define i32 @shift1(i32 %A, i32 %B) { |
| %C = lshr exact i32 %A, %B |
| %D = shl nuw i32 %C, %B |
| ret i32 %D |
| } |
| |
| ; CHECK: @shift2 |
| ; CHECK: lshr |
| ; CHECK: ret i32 %D |
| define i32 @shift2(i32 %A, i32 %B) { |
| %C = lshr i32 %A, %B |
| %D = shl nuw i32 %C, %B |
| ret i32 %D |
| } |
| |
| ; CHECK: @shift3 |
| ; CHECK: ret i32 %A |
| define i32 @shift3(i32 %A, i32 %B) { |
| %C = ashr exact i32 %A, %B |
| %D = shl nuw i32 %C, %B |
| ret i32 %D |
| } |
| |
| ; CHECK: @shift4 |
| ; CHECK: ret i32 %A |
| define i32 @shift4(i32 %A, i32 %B) { |
| %C = shl nuw i32 %A, %B |
| %D = lshr i32 %C, %B |
| ret i32 %D |
| } |
| |
| ; CHECK: @shift5 |
| ; CHECK: ret i32 %A |
| define i32 @shift5(i32 %A, i32 %B) { |
| %C = shl nsw i32 %A, %B |
| %D = ashr i32 %C, %B |
| ret i32 %D |
| } |