tree f38443eb3ee03b51ad5a2dfe6d4aee74ee9511b7
parent 75bab9249d2dace814fb5cde6be19760ddee7731
author John Stiles <johnstiles@google.com> 1630352820 -0400
committer SkCQ <skcq-be@skia-corp.google.com.iam.gserviceaccount.com> 1630356017 +0000

Fix flaws in minus-prefix optimization.

We had a logic bug when attempting to optimize the following code:
    const vecN x = vecN(a, b, c);
    -x;

The goal was to replace `-x` with `vecN(-a, -b, -c)` but we accidentally
tried to cast the `x` VariableReference to a Constructor. We
unfortunately didn't cover this in any of our test cases, but the fuzzer
managed to synthesize it by mixing and matching elements from its new
corpus.

This affected several different constructor types: splat, diagonal-
matrix, compound and array.

Change-Id: I10dd2460ab26ba3e820b0cff5db091368fb7e648
Bug: oss-fuzz:37764, oss-fuzz:37861
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/443407
Commit-Queue: John Stiles <johnstiles@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>