reuse negates where possible instead of always creating them from scratch.
This allows us to optimize test12 into:
define i32 @test12(i32 %X) {
%factor = mul i32 %X, -3 ; <i32> [#uses=1]
%Z = add i32 %factor, 6 ; <i32> [#uses=1]
ret i32 %Z
}
instead of:
define i32 @test12(i32 %X) {
%Y = sub i32 6, %X ; <i32> [#uses=1]
%C = sub i32 %Y, %X ; <i32> [#uses=1]
%Z = sub i32 %C, %X ; <i32> [#uses=1]
ret i32 %Z
}
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92373
91177308-0d34-0410-b5e6-
96231b3b80d8