Roll SwiftShader from 542593f0e311 to 7a571328541a (2 revisions)

https://swiftshader.googlesource.com/SwiftShader.git/+log/542593f0e311..7a571328541a

2021-11-02 sugoi@google.com Perform all blend operations in floating-point
2021-11-02 swiftshader.regress@gmail.com Regres: Update test lists @ 542593f0

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/swiftshader-angle-autoroll
Please CC cnorthrop@google.com on the revert to ensure that a human
is aware of the problem.

To file a bug in SwiftShader: https://bugs.chromium.org/p/swiftshader/issues/entry
To file a bug in ANGLE: https://bugs.chromium.org/p/angleproject/issues/entry

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md

Bug: None
Tbr: cnorthrop@google.com
Change-Id: I1cd36fbf0483351d4d9b30be3108dafc366364e1
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3259062
Commit-Queue: angle-autoroll <angle-autoroll@skia-public.iam.gserviceaccount.com>
Bot-Commit: angle-autoroll <angle-autoroll@skia-public.iam.gserviceaccount.com>

DEPS

@@ -496,7 +496,7 @@ deps = {
   },
 
   'third_party/SwiftShader': {
-    'url': '{swiftshader_git}/SwiftShader@542593f0e3116c8e3dc9dd5d389aafa0438ffba5',
+    'url': '{swiftshader_git}/SwiftShader@7a571328541a7c4c8b6a203877b551fa18b17d86',
     'condition': 'not build_with_chromium',
   },