tree 9b0d3dd767c6792e3fcdb7852dde6f1de49c590d
parent 0540e683d4fc5116d1839ca7b4259146d7b127a0
author Nicolas Capens <capn@google.com> 1613066863 -0500
committer Nicolas Capens <nicolascapens@google.com> 1613759371 +0000

Eliminate code randomization support from Subzero

SwiftShader has no use for this since shader execution with robustness
features enabled can not access memory outside of the graphics
resources. For Chromium it also runs in the GPU process, which isolates
it from browser-wide and even tab renderer data and code, and also has
its own sandboxing.

If we ever do need randomization to prevent attacks, and project Bunker
doesn't provide the needed site isolation, it should be implemented
either at the Reactor level or as separate transformation passes where
possible.

While previously this feature was already disabled, there might have
been inadvertent randomization which could explain our test time
variability. It may also improve code generation performance a bit to
not have this code around any more.

Bug: b/179832693
Change-Id: If1ccb54981edb61f443dd5949c56b75bab07c7c2
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/52808
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
Presubmit-Ready: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>