The Tor Browser: gfx/angle/src/compiler/VersionGLSL.cpp@97036ab72558 (annotated)

gfx/angle/src/compiler/VersionGLSL.cpp@97036ab72558 (annotated)

gfx/angle/src/compiler/VersionGLSL.cpp

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 //
 // Copyright (c) 2002-2012 The ANGLE Project Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 #include "compiler/VersionGLSL.h"
 static const int GLSL_VERSION_110 = 110;
 static const int GLSL_VERSION_120 = 120;
 // We need to scan for the following:
 // 1. "invariant" keyword: This can occur in both - vertex and fragment shaders
 //    but only at the global scope.
 // 2. "gl_PointCoord" built-in variable: This can only occur in fragment shader
 //    but inside any scope.
 // 3. Call to a matrix constructor with another matrix as argument.
 //    (These constructors were reserved in GLSL version 1.10.)
 // 4. Arrays as "out" function parameters.
 //    GLSL spec section 6.1.1: "When calling a function, expressions that do
 //    not evaluate to l-values cannot be passed to parameters declared as
 //    out or inout."
 //    GLSL 1.1 section 5.8: "Other binary or unary expressions,
 //    non-dereferenced arrays, function names, swizzles with repeated fields,
 //    and constants cannot be l-values."
 //    GLSL 1.2 relaxed the restriction on arrays, section 5.8: "Variables that
 //    are built-in types, entire structures or arrays... are all l-values."
 //
 // TODO(alokp): The following two cases of invariant decalaration get lost
 // during parsing - they do not get carried over to the intermediate tree.
 // Handle these cases:
 // 1. When a pragma is used to force all output variables to be invariant:
 //    - #pragma STDGL invariant(all)
 // 2. When a previously decalared or built-in variable is marked invariant:
 //    - invariant gl_Position;
 //    - varying vec3 color; invariant color;
 //
 TVersionGLSL::TVersionGLSL(ShShaderType type)
     : mShaderType(type),
       mVersion(GLSL_VERSION_110)
 {
 }
 void TVersionGLSL::visitSymbol(TIntermSymbol* node)
 {
     if (node->getSymbol() == "gl_PointCoord")
         updateVersion(GLSL_VERSION_120);
 }
 void TVersionGLSL::visitConstantUnion(TIntermConstantUnion*)
 {
 }
 bool TVersionGLSL::visitBinary(Visit, TIntermBinary*)
 {
     return true;
 }
 bool TVersionGLSL::visitUnary(Visit, TIntermUnary*)
 {
     return true;
 }
 bool TVersionGLSL::visitSelection(Visit, TIntermSelection*)
 {
     return true;
 }
 bool TVersionGLSL::visitAggregate(Visit, TIntermAggregate* node)
 {
     bool visitChildren = true;
     switch (node->getOp()) {
       case EOpSequence:
         // We need to visit sequence children to get to global or inner scope.
         visitChildren = true;
         break;
       case EOpDeclaration: {
         const TIntermSequence& sequence = node->getSequence();
         TQualifier qualifier = sequence.front()->getAsTyped()->getQualifier();
         if ((qualifier == EvqInvariantVaryingIn) ||
             (qualifier == EvqInvariantVaryingOut)) {
             updateVersion(GLSL_VERSION_120);
         }
         break;
       }
       case EOpParameters: {
         const TIntermSequence& params = node->getSequence();
         for (TIntermSequence::const_iterator iter = params.begin();
              iter != params.end(); ++iter)
         {
             const TIntermTyped* param = (*iter)->getAsTyped();
             if (param->isArray())
             {
                 TQualifier qualifier = param->getQualifier();
                 if ((qualifier == EvqOut) || (qualifier ==  EvqInOut))
                 {
                     updateVersion(GLSL_VERSION_120);
                     break;
                 }
             }
         }
         // Fully processed. No need to visit children.
         visitChildren = false;
         break;
       }
       case EOpConstructMat2:
       case EOpConstructMat3:
       case EOpConstructMat4: {
         const TIntermSequence& sequence = node->getSequence();
         if (sequence.size() == 1) {
           TIntermTyped* typed = sequence.front()->getAsTyped();
           if (typed && typed->isMatrix()) {
             updateVersion(GLSL_VERSION_120);
           }
         }
         break;
       }
       default: break;
     }
     return visitChildren;
 }
 bool TVersionGLSL::visitLoop(Visit, TIntermLoop*)
 {
     return true;
 }
 bool TVersionGLSL::visitBranch(Visit, TIntermBranch*)
 {
     return true;
 }
 void TVersionGLSL::updateVersion(int version)
 {
     mVersion = std::max(version, mVersion);
 }

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gfx/angle/src/compiler/VersionGLSL.cpp@97036ab72558 (annotated)

gfx/angle/src/compiler/VersionGLSL.cpp