dolphin/Externals/glslang/hlsl/hlslTokenStream.cpp

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C++
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//
// Copyright (C) 2016 Google, Inc.
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
//
// Neither the name of Google, Inc., nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
// COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
// BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
#include "hlslTokenStream.h"
namespace glslang {
void HlslTokenStream::pushPreToken(const HlslToken& tok)
{
assert(preTokenStackSize < tokenBufferSize);
preTokenStack[preTokenStackSize++] = tok;
}
HlslToken HlslTokenStream::popPreToken()
{
assert(preTokenStackSize > 0);
return preTokenStack[--preTokenStackSize];
}
void HlslTokenStream::pushTokenBuffer(const HlslToken& tok)
{
tokenBuffer[tokenBufferPos] = tok;
tokenBufferPos = (tokenBufferPos+1) % tokenBufferSize;
}
HlslToken HlslTokenStream::popTokenBuffer()
{
// Back up
tokenBufferPos = (tokenBufferPos+tokenBufferSize-1) % tokenBufferSize;
return tokenBuffer[tokenBufferPos];
}
//
// Make a new source of tokens, not from the source, but from an
// already pre-processed token stream.
//
// This interrupts current token processing which must be restored
// later. Some simplifying assumptions are made (and asserted).
//
void HlslTokenStream::pushTokenStream(const TVector<HlslToken>* tokens)
{
// not yet setup to interrupt a stream that has been receded
// and not yet reconsumed
assert(preTokenStackSize == 0);
// save current state
currentTokenStack.push_back(token);
// set up new token stream
tokenStreamStack.push_back(tokens);
// start position at first token:
token = (*tokens)[0];
tokenPosition.push_back(0);
}
// Undo pushTokenStream(), see above
void HlslTokenStream::popTokenStream()
{
tokenStreamStack.pop_back();
tokenPosition.pop_back();
token = currentTokenStack.back();
currentTokenStack.pop_back();
}
// Load 'token' with the next token in the stream of tokens.
void HlslTokenStream::advanceToken()
{
pushTokenBuffer(token);
if (preTokenStackSize > 0)
token = popPreToken();
else {
if (tokenStreamStack.size() == 0)
scanner.tokenize(token);
else {
++tokenPosition.back();
if (tokenPosition.back() >= (int)tokenStreamStack.back()->size())
token.tokenClass = EHTokNone;
else
token = (*tokenStreamStack.back())[tokenPosition.back()];
}
}
}
void HlslTokenStream::recedeToken()
{
pushPreToken(token);
token = popTokenBuffer();
}
// Return the current token class.
EHlslTokenClass HlslTokenStream::peek() const
{
return token.tokenClass;
}
// Return true, without advancing to the next token, if the current token is
// the expected (passed in) token class.
bool HlslTokenStream::peekTokenClass(EHlslTokenClass tokenClass) const
{
return peek() == tokenClass;
}
// Return true and advance to the next token if the current token is the
// expected (passed in) token class.
bool HlslTokenStream::acceptTokenClass(EHlslTokenClass tokenClass)
{
if (peekTokenClass(tokenClass)) {
advanceToken();
return true;
}
return false;
}
} // end namespace glslang