| ; RUN: opt < %s -reassociate -instcombine -S | FileCheck %s |
| |
| ; With sub reassociation, constant folding can eliminate the 12 and -12 constants. |
| define i32 @test1(i32 %A, i32 %B) { |
| ; CHECK-LABEL: @test1( |
| ; CHECK-NEXT: [[Z:%.*]] = sub i32 %A, %B |
| ; CHECK-NEXT: ret i32 [[Z]] |
| ; |
| %X = add i32 -12, %A |
| %Y = sub i32 %X, %B |
| %Z = add i32 %Y, 12 |
| ret i32 %Z |
| } |
| |
| ; PR2047 |
| ; With sub reassociation, constant folding can eliminate the uses of %a. |
| define i32 @test2(i32 %a, i32 %b, i32 %c) { |
| ; CHECK-LABEL: @test2( |
| ; CHECK-NEXT: [[SUM:%.*]] = add i32 %c, %b |
| ; CHECK-NEXT: [[TMP7:%.*]] = sub i32 0, [[SUM]] |
| ; CHECK-NEXT: ret i32 [[TMP7]] |
| ; |
| %tmp3 = sub i32 %a, %b |
| %tmp5 = sub i32 %tmp3, %c |
| %tmp7 = sub i32 %tmp5, %a |
| ret i32 %tmp7 |
| } |
| |
