1 files changed, 214 insertions, 0 deletions
diff --git a/gfx/angle/src/compiler/translator/LoopInfo.cpp b/gfx/angle/src/compiler/translator/LoopInfo.cpp
new file mode 100755
index 000000000..48fa24472
--- /dev/null
+++ b/gfx/angle/src/compiler/translator/LoopInfo.cpp
@@ -0,0 +1,214 @@
+//
+// Copyright (c) 2002-2014 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/translator/LoopInfo.h"
+
+namespace sh
+{
+
+namespace
+{
+
+int EvaluateIntConstant(TIntermConstantUnion *node)
+{
+    ASSERT(node && node->getUnionArrayPointer());
+    return node->getIConst(0);
+}
+
+int GetLoopIntIncrement(TIntermLoop *node)
+{
+    TIntermNode *expr = node->getExpression();
+    // for expression has one of the following forms:
+    //     loop_index++
+    //     loop_index--
+    //     loop_index += constant_expression
+    //     loop_index -= constant_expression
+    //     ++loop_index
+    //     --loop_index
+    // The last two forms are not specified in the spec, but I am assuming
+    // its an oversight.
+    TIntermUnary *unOp = expr->getAsUnaryNode();
+    TIntermBinary *binOp = unOp ? NULL : expr->getAsBinaryNode();
+
+    TOperator op = EOpNull;
+    TIntermConstantUnion *incrementNode = NULL;
+    if (unOp)
+    {
+        op = unOp->getOp();
+    }
+    else if (binOp)
+    {
+        op = binOp->getOp();
+        ASSERT(binOp->getRight());
+        incrementNode = binOp->getRight()->getAsConstantUnion();
+        ASSERT(incrementNode);
+    }
+
+    int increment = 0;
+    // The operator is one of: ++ -- += -=.
+    switch (op)
+    {
+      case EOpPostIncrement:
+      case EOpPreIncrement:
+        ASSERT(unOp && !binOp);
+        increment = 1;
+        break;
+      case EOpPostDecrement:
+      case EOpPreDecrement:
+        ASSERT(unOp && !binOp);
+        increment = -1;
+        break;
+      case EOpAddAssign:
+        ASSERT(!unOp && binOp);
+        increment = EvaluateIntConstant(incrementNode);
+        break;
+      case EOpSubAssign:
+        ASSERT(!unOp && binOp);
+        increment = - EvaluateIntConstant(incrementNode);
+        break;
+      default:
+        UNREACHABLE();
+    }
+
+    return increment;
+}
+
+}  // namespace anonymous
+
+TLoopIndexInfo::TLoopIndexInfo()
+    : mId(-1),
+      mType(EbtVoid),
+      mInitValue(0),
+      mStopValue(0),
+      mIncrementValue(0),
+      mOp(EOpNull),
+      mCurrentValue(0)
+{
+}
+
+void TLoopIndexInfo::fillInfo(TIntermLoop *node)
+{
+    if (node == NULL)
+        return;
+
+    // Here we assume all the operations are valid, because the loop node is
+    // already validated in ValidateLimitations.
+    TIntermSequence *declSeq = node->getInit()->getAsDeclarationNode()->getSequence();
+    TIntermBinary *declInit = (*declSeq)[0]->getAsBinaryNode();
+    TIntermSymbol *symbol = declInit->getLeft()->getAsSymbolNode();
+
+    mId = symbol->getId();
+    mType = symbol->getBasicType();
+
+    if (mType == EbtInt)
+    {
+        TIntermConstantUnion* initNode = declInit->getRight()->getAsConstantUnion();
+        mInitValue = EvaluateIntConstant(initNode);
+        mCurrentValue = mInitValue;
+        mIncrementValue = GetLoopIntIncrement(node);
+
+        TIntermBinary* binOp = node->getCondition()->getAsBinaryNode();
+        mStopValue = EvaluateIntConstant(
+            binOp->getRight()->getAsConstantUnion());
+        mOp = binOp->getOp();
+    }
+}
+
+bool TLoopIndexInfo::satisfiesLoopCondition() const
+{
+    // Relational operator is one of: > >= < <= == or !=.
+    switch (mOp)
+    {
+      case EOpEqual:
+        return (mCurrentValue == mStopValue);
+      case EOpNotEqual:
+        return (mCurrentValue != mStopValue);
+      case EOpLessThan:
+        return (mCurrentValue < mStopValue);
+      case EOpGreaterThan:
+        return (mCurrentValue > mStopValue);
+      case EOpLessThanEqual:
+        return (mCurrentValue <= mStopValue);
+      case EOpGreaterThanEqual:
+        return (mCurrentValue >= mStopValue);
+      default:
+        UNREACHABLE();
+        return false;
+    }
+}
+
+TLoopInfo::TLoopInfo()
+    : loop(NULL)
+{
+}
+
+TLoopInfo::TLoopInfo(TIntermLoop *node)
+    : loop(node)
+{
+    index.fillInfo(node);
+}
+
+TIntermLoop *TLoopStack::findLoop(TIntermSymbol *symbol)
+{
+    if (!symbol)
+        return NULL;
+    for (iterator iter = begin(); iter != end(); ++iter)
+    {
+        if (iter->index.getId() == symbol->getId())
+            return iter->loop;
+    }
+    return NULL;
+}
+
+TLoopIndexInfo *TLoopStack::getIndexInfo(TIntermSymbol *symbol)
+{
+    if (!symbol)
+        return NULL;
+    for (iterator iter = begin(); iter != end(); ++iter)
+    {
+        if (iter->index.getId() == symbol->getId())
+            return &(iter->index);
+    }
+    return NULL;
+}
+
+void TLoopStack::step()
+{
+    ASSERT(!empty());
+    rbegin()->index.step();
+}
+
+bool TLoopStack::satisfiesLoopCondition()
+{
+    ASSERT(!empty());
+    return rbegin()->index.satisfiesLoopCondition();
+}
+
+bool TLoopStack::needsToReplaceSymbolWithValue(TIntermSymbol *symbol)
+{
+    TIntermLoop *loop = findLoop(symbol);
+    return loop && loop->getUnrollFlag();
+}
+
+int TLoopStack::getLoopIndexValue(TIntermSymbol *symbol)
+{
+    TLoopIndexInfo *info = getIndexInfo(symbol);
+    ASSERT(info);
+    return info->getCurrentValue();
+}
+
+void TLoopStack::push(TIntermLoop *loop)
+{
+    TLoopInfo info(loop);
+    push_back(info);
+}
+
+void TLoopStack::pop()
+{
+    pop_back();
+}
+
+}  // namespace sh