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//
// Copyright 2019 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.
//
// NameNamelessUniformBuffers: Gives nameless uniform buffer variables internal names.
//
#include "compiler/translator/tree_ops/NameNamelessUniformBuffers.h"
#include "compiler/translator/SymbolTable.h"
#include "compiler/translator/tree_util/IntermNode_util.h"
#include "compiler/translator/tree_util/IntermTraverse.h"
namespace sh
{
namespace
{
// Traverse uniform buffer declarations and give name to nameless declarations. Keeps track of
// the interface fields which will be used in the source without the interface block variable name
// and replaces them with name.field.
class NameUniformBufferVariablesTraverser : public TIntermTraverser
{
public:
explicit NameUniformBufferVariablesTraverser(TSymbolTable *symbolTable)
: TIntermTraverser(true, false, false, symbolTable)
{}
bool visitDeclaration(Visit visit, TIntermDeclaration *decl) override
{
ASSERT(visit == PreVisit);
const TIntermSequence &sequence = *(decl->getSequence());
TIntermTyped *variableNode = sequence.front()->getAsTyped();
const TType &type = variableNode->getType();
// If it's an interface block, it may have to be converted if it contains any row-major
// fields.
if (!type.isInterfaceBlock())
{
return true;
}
// Multi declaration statements are already separated, so there can only be one variable
// here.
ASSERT(sequence.size() == 1);
const TVariable *variable = &variableNode->getAsSymbolNode()->variable();
if (variable->symbolType() != SymbolType::Empty)
{
return false;
}
TIntermDeclaration *newDeclaration = new TIntermDeclaration;
TVariable *newVariable = new TVariable(mSymbolTable, kEmptyImmutableString, &type,
SymbolType::AngleInternal, variable->extensions());
newDeclaration->appendDeclarator(new TIntermSymbol(newVariable));
queueReplacement(newDeclaration, OriginalNode::IS_DROPPED);
// It's safe to key the map with the interface block, as there couldn't have been multiple
// declarations with this interface block (as the variable is nameless), so for nameless
// uniform buffers, the interface block is unique.
mNamelessUniformBuffersMap[type.getInterfaceBlock()] = newVariable;
return false;
}
void visitSymbol(TIntermSymbol *symbol) override
{
const TType &type = symbol->getType();
// The symbols we are looking for have the interface block pointer set, but are not
// interface blocks. These are references to fields of nameless uniform buffers.
if (type.isInterfaceBlock() || type.getInterfaceBlock() == nullptr)
{
return;
}
const TInterfaceBlock *block = type.getInterfaceBlock();
// If block variable is not nameless, there's nothing to do.
if (mNamelessUniformBuffersMap.count(block) == 0)
{
return;
}
const ImmutableString symbolName = symbol->getName();
// Find which field it is
const TVector<TField *> fields = block->fields();
for (size_t fieldIndex = 0; fieldIndex < fields.size(); ++fieldIndex)
{
const TField *field = fields[fieldIndex];
if (field->name() != symbolName)
{
continue;
}
// Replace this node with a binary node that indexes the named uniform buffer.
TIntermSymbol *namedUniformBuffer =
new TIntermSymbol(mNamelessUniformBuffersMap[block]);
TIntermBinary *replacement =
new TIntermBinary(EOpIndexDirectInterfaceBlock, namedUniformBuffer,
CreateIndexNode(static_cast<uint32_t>(fieldIndex)));
queueReplacement(replacement, OriginalNode::IS_DROPPED);
return;
}
UNREACHABLE();
}
private:
// A map from nameless uniform buffers to their named replacements.
std::unordered_map<const TInterfaceBlock *, const TVariable *> mNamelessUniformBuffersMap;
};
} // anonymous namespace
bool NameNamelessUniformBuffers(TCompiler *compiler, TIntermBlock *root, TSymbolTable *symbolTable)
{
NameUniformBufferVariablesTraverser nameUniformBufferVariables(symbolTable);
root->traverse(&nameUniformBufferVariables);
return nameUniformBufferVariables.updateTree(compiler, root);
}
} // namespace sh