Add the SH_TIMING_RESTRICTIONS compile flag and dependency graph implementation.
Description of the algorithm:
http://code.google.com/p/mvujovic/wiki/ShaderControlFlowAnalysis
This flag is one potential solution to timing attacks on textures containing cross-domain content
or user agent data.
This kind of analysis could be useful for both WebGL and CSS Shaders.
The SH_TIMING_RESTRICTIONS flag will reject a shader if it uses texture dependent data to affect
control flow.
Other ways of affecting shader timing such as using NaNs in basic arithmetic operations or using
built-in functions (e.g. atan) with different inputs are still under investigation.
Issue=329
Review URL: http://codereview.appspot.com/6195062/
git-svn-id: https://angleproject.googlecode.com/svn/trunk@1101 736b8ea6-26fd-11df-bfd4-992fa37f6226
19 files changed