gfx/angle/src/compiler/UnfoldShortCircuit.cpp@97036ab72558 (annotated)
gfx/angle/src/compiler/UnfoldShortCircuit.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.
| michael@0 | 1 | // |
| michael@0 | 2 | // Copyright (c) 2002-2013 The ANGLE Project Authors. All rights reserved. |
| michael@0 | 3 | // Use of this source code is governed by a BSD-style license that can be |
| michael@0 | 4 | // found in the LICENSE file. |
| michael@0 | 5 | // |
| michael@0 | 6 | // UnfoldShortCircuit is an AST traverser to output short-circuiting operators as if-else statements. |
| michael@0 | 7 | // The results are assigned to s# temporaries, which are used by the main translator instead of |
| michael@0 | 8 | // the original expression. |
| michael@0 | 9 | // |
| michael@0 | 10 | |
| michael@0 | 11 | #include "compiler/UnfoldShortCircuit.h" |
| michael@0 | 12 | |
| michael@0 | 13 | #include "compiler/InfoSink.h" |
| michael@0 | 14 | #include "compiler/OutputHLSL.h" |
| michael@0 | 15 | |
| michael@0 | 16 | namespace sh |
| michael@0 | 17 | { |
| michael@0 | 18 | UnfoldShortCircuit::UnfoldShortCircuit(TParseContext &context, OutputHLSL *outputHLSL) : mContext(context), mOutputHLSL(outputHLSL) |
| michael@0 | 19 | { |
| michael@0 | 20 | mTemporaryIndex = 0; |
| michael@0 | 21 | } |
| michael@0 | 22 | |
| michael@0 | 23 | void UnfoldShortCircuit::traverse(TIntermNode *node) |
| michael@0 | 24 | { |
| michael@0 | 25 | int rewindIndex = mTemporaryIndex; |
| michael@0 | 26 | node->traverse(this); |
| michael@0 | 27 | mTemporaryIndex = rewindIndex; |
| michael@0 | 28 | } |
| michael@0 | 29 | |
| michael@0 | 30 | bool UnfoldShortCircuit::visitBinary(Visit visit, TIntermBinary *node) |
| michael@0 | 31 | { |
| michael@0 | 32 | TInfoSinkBase &out = mOutputHLSL->getBodyStream(); |
| michael@0 | 33 | |
| michael@0 | 34 | switch (node->getOp()) |
| michael@0 | 35 | { |
| michael@0 | 36 | case EOpLogicalOr: |
| michael@0 | 37 | // "x || y" is equivalent to "x ? true : y", which unfolds to "bool s; if(x) s = true; else s = y;", |
| michael@0 | 38 | // and then further simplifies down to "bool s = x; if(!s) s = y;". |
| michael@0 | 39 | { |
| michael@0 | 40 | int i = mTemporaryIndex; |
| michael@0 | 41 | |
| michael@0 | 42 | out << "bool s" << i << ";\n"; |
| michael@0 | 43 | |
| michael@0 | 44 | out << "{\n"; |
| michael@0 | 45 | |
| michael@0 | 46 | mTemporaryIndex = i + 1; |
| michael@0 | 47 | node->getLeft()->traverse(this); |
| michael@0 | 48 | out << "s" << i << " = "; |
| michael@0 | 49 | mTemporaryIndex = i + 1; |
| michael@0 | 50 | node->getLeft()->traverse(mOutputHLSL); |
| michael@0 | 51 | out << ";\n"; |
| michael@0 | 52 | out << "if(!s" << i << ")\n" |
| michael@0 | 53 | "{\n"; |
| michael@0 | 54 | mTemporaryIndex = i + 1; |
| michael@0 | 55 | node->getRight()->traverse(this); |
| michael@0 | 56 | out << " s" << i << " = "; |
| michael@0 | 57 | mTemporaryIndex = i + 1; |
| michael@0 | 58 | node->getRight()->traverse(mOutputHLSL); |
| michael@0 | 59 | out << ";\n" |
| michael@0 | 60 | "}\n"; |
| michael@0 | 61 | |
| michael@0 | 62 | out << "}\n"; |
| michael@0 | 63 | |
| michael@0 | 64 | mTemporaryIndex = i + 1; |
| michael@0 | 65 | } |
| michael@0 | 66 | return false; |
| michael@0 | 67 | case EOpLogicalAnd: |
| michael@0 | 68 | // "x && y" is equivalent to "x ? y : false", which unfolds to "bool s; if(x) s = y; else s = false;", |
| michael@0 | 69 | // and then further simplifies down to "bool s = x; if(s) s = y;". |
| michael@0 | 70 | { |
| michael@0 | 71 | int i = mTemporaryIndex; |
| michael@0 | 72 | |
| michael@0 | 73 | out << "bool s" << i << ";\n"; |
| michael@0 | 74 | |
| michael@0 | 75 | out << "{\n"; |
| michael@0 | 76 | |
| michael@0 | 77 | mTemporaryIndex = i + 1; |
| michael@0 | 78 | node->getLeft()->traverse(this); |
| michael@0 | 79 | out << "s" << i << " = "; |
| michael@0 | 80 | mTemporaryIndex = i + 1; |
| michael@0 | 81 | node->getLeft()->traverse(mOutputHLSL); |
| michael@0 | 82 | out << ";\n"; |
| michael@0 | 83 | out << "if(s" << i << ")\n" |
| michael@0 | 84 | "{\n"; |
| michael@0 | 85 | mTemporaryIndex = i + 1; |
| michael@0 | 86 | node->getRight()->traverse(this); |
| michael@0 | 87 | out << " s" << i << " = "; |
| michael@0 | 88 | mTemporaryIndex = i + 1; |
| michael@0 | 89 | node->getRight()->traverse(mOutputHLSL); |
| michael@0 | 90 | out << ";\n" |
| michael@0 | 91 | "}\n"; |
| michael@0 | 92 | |
| michael@0 | 93 | out << "}\n"; |
| michael@0 | 94 | |
| michael@0 | 95 | mTemporaryIndex = i + 1; |
| michael@0 | 96 | } |
| michael@0 | 97 | return false; |
| michael@0 | 98 | default: |
| michael@0 | 99 | return true; |
| michael@0 | 100 | } |
| michael@0 | 101 | } |
| michael@0 | 102 | |
| michael@0 | 103 | bool UnfoldShortCircuit::visitSelection(Visit visit, TIntermSelection *node) |
| michael@0 | 104 | { |
| michael@0 | 105 | TInfoSinkBase &out = mOutputHLSL->getBodyStream(); |
| michael@0 | 106 | |
| michael@0 | 107 | // Unfold "b ? x : y" into "type s; if(b) s = x; else s = y;" |
| michael@0 | 108 | if (node->usesTernaryOperator()) |
| michael@0 | 109 | { |
| michael@0 | 110 | int i = mTemporaryIndex; |
| michael@0 | 111 | |
| michael@0 | 112 | out << mOutputHLSL->typeString(node->getType()) << " s" << i << ";\n"; |
| michael@0 | 113 | |
| michael@0 | 114 | out << "{\n"; |
| michael@0 | 115 | |
| michael@0 | 116 | mTemporaryIndex = i + 1; |
| michael@0 | 117 | node->getCondition()->traverse(this); |
| michael@0 | 118 | out << "if("; |
| michael@0 | 119 | mTemporaryIndex = i + 1; |
| michael@0 | 120 | node->getCondition()->traverse(mOutputHLSL); |
| michael@0 | 121 | out << ")\n" |
| michael@0 | 122 | "{\n"; |
| michael@0 | 123 | mTemporaryIndex = i + 1; |
| michael@0 | 124 | node->getTrueBlock()->traverse(this); |
| michael@0 | 125 | out << " s" << i << " = "; |
| michael@0 | 126 | mTemporaryIndex = i + 1; |
| michael@0 | 127 | node->getTrueBlock()->traverse(mOutputHLSL); |
| michael@0 | 128 | out << ";\n" |
| michael@0 | 129 | "}\n" |
| michael@0 | 130 | "else\n" |
| michael@0 | 131 | "{\n"; |
| michael@0 | 132 | mTemporaryIndex = i + 1; |
| michael@0 | 133 | node->getFalseBlock()->traverse(this); |
| michael@0 | 134 | out << " s" << i << " = "; |
| michael@0 | 135 | mTemporaryIndex = i + 1; |
| michael@0 | 136 | node->getFalseBlock()->traverse(mOutputHLSL); |
| michael@0 | 137 | out << ";\n" |
| michael@0 | 138 | "}\n"; |
| michael@0 | 139 | |
| michael@0 | 140 | out << "}\n"; |
| michael@0 | 141 | |
| michael@0 | 142 | mTemporaryIndex = i + 1; |
| michael@0 | 143 | } |
| michael@0 | 144 | |
| michael@0 | 145 | return false; |
| michael@0 | 146 | } |
| michael@0 | 147 | |
| michael@0 | 148 | bool UnfoldShortCircuit::visitLoop(Visit visit, TIntermLoop *node) |
| michael@0 | 149 | { |
| michael@0 | 150 | int rewindIndex = mTemporaryIndex; |
| michael@0 | 151 | |
| michael@0 | 152 | if (node->getInit()) |
| michael@0 | 153 | { |
| michael@0 | 154 | node->getInit()->traverse(this); |
| michael@0 | 155 | } |
| michael@0 | 156 | |
| michael@0 | 157 | if (node->getCondition()) |
| michael@0 | 158 | { |
| michael@0 | 159 | node->getCondition()->traverse(this); |
| michael@0 | 160 | } |
| michael@0 | 161 | |
| michael@0 | 162 | if (node->getExpression()) |
| michael@0 | 163 | { |
| michael@0 | 164 | node->getExpression()->traverse(this); |
| michael@0 | 165 | } |
| michael@0 | 166 | |
| michael@0 | 167 | mTemporaryIndex = rewindIndex; |
| michael@0 | 168 | |
| michael@0 | 169 | return false; |
| michael@0 | 170 | } |
| michael@0 | 171 | |
| michael@0 | 172 | int UnfoldShortCircuit::getNextTemporaryIndex() |
| michael@0 | 173 | { |
| michael@0 | 174 | return mTemporaryIndex++; |
| michael@0 | 175 | } |
| michael@0 | 176 | } |
