test/Transforms/InstCombine/2002-05-14-SubFailure.ll - llvm - Git at Google

 ; Instcombine was missing a test that caused it to make illegal transformations
 ; sometimes.  In this case, it transforms the sub into an add:
 ; RUN: opt < %s -instcombine -S | grep sub
 ;
 define i32 @test(i32 %i, i32 %j) {
         %A = mul i32 %i, %j
         %B = sub i32 2, %A
         ret i32 %B
 }
	; Instcombine was missing a test that caused it to make illegal transformations
	; sometimes. In this case, it transforms the sub into an add:
	; RUN: opt < %s -instcombine -S \| grep sub
	;
	define i32 @test(i32 %i, i32 %j) {
	%A = mul i32 %i, %j
	%B = sub i32 2, %A
	ret i32 %B
	}