| ; 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 | |
| } |