aa5a8c482e
Some Metal devices have a bug where storage resources can still be written to even if the fragment is discarded. This is obviously a bug in Metal, but bothering Apple to fix it will only fix it for newer versions; therefore, a workaround is needed for older versions. I have made this an option so that, in case the bug is ever fixed, the workaround can be disabled. This workaround is simple: if a fragment shader may discard its fragment and writes to a storage resource, a variable representing the `HelperInvocation` built-in is created and passed to all functions. The flag is checked on all resource writes; writes do not occur when `HelperInvocation` is `true`. This relies on the earlier workaround to update `HelperInvocation` when the fragment is discarded. Fixes at least 3 failures in the CTS. |
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| .. | ||
| opt | ||
| shaders | ||
| shaders-hlsl | ||
| shaders-hlsl-no-opt | ||
| shaders-msl | ||
| shaders-msl-no-opt | ||
| shaders-no-opt | ||
| shaders-reflection | ||
| shaders-ue4/asm | ||
| shaders-ue4-no-opt/asm | ||