Fix misdetection of dead global variables.
A global variable should be considered "dead" if it's never written and
never read. The previous code checked if it was never written OR never
read, which is not the same.
This would generate GLSL/Metal that didn't compile. In SPIR-V, it would
SkASSERT, then crash, during codegen. The fuzzer was able to detect the
SPIR-V issue, but it was wrong in all three cases.
Change-Id: Id59a2499eb5baa3839b93826bfbc24191bfd490b
Bug: oss-fuzz:32005
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/385280
Commit-Queue: John Stiles <johnstiles@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
5 files changed