chromium/third_party/angle/src/compiler/translator/tree_ops/RewriteArrayOfArrayOfOpaqueUniforms.cpp

//
// 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.
//
// RewriteAtomicCounters: Emulate atomic counter buffers with storage buffers.
//

#include "compiler/translator/tree_ops/RewriteArrayOfArrayOfOpaqueUniforms.h"

#include "compiler/translator/Compiler.h"
#include "compiler/translator/ImmutableStringBuilder.h"
#include "compiler/translator/SymbolTable.h"
#include "compiler/translator/tree_util/IntermNode_util.h"
#include "compiler/translator/tree_util/IntermTraverse.h"
#include "compiler/translator/tree_util/ReplaceVariable.h"

namespace sh
{
namespace
{
struct UniformData
{ … };

UniformMap;

TIntermTyped *RewriteArrayOfArraySubscriptExpression(TCompiler *compiler,
                                                     TIntermBinary *node,
                                                     const UniformMap &uniformMap);

// Given an expression, this traverser calculates a new expression where array of array of opaque
// uniforms are replaced with their flattened ones.  In particular, this is run on the right node of
// EOpIndexIndirect binary nodes, so that the expression in the index gets a chance to go through
// this transformation.
class RewriteExpressionTraverser final : public TIntermTraverser
{ … };

// Rewrite the index of an EOpIndexIndirect expression.  The root can never need replacing, because
// it cannot be an opaque uniform itself.
void RewriteIndexExpression(TCompiler *compiler,
                            TIntermTyped *expression,
                            const UniformMap &uniformMap)
{ … }

// Given an expression such as the following:
//
//                                              EOpIndex(In)Direct (opaque uniform)
//                                                    /           \
//                                            EOpIndex(In)Direct   I1
//                                                  /           \
//                                                ...            I2
//                                            /
//                                    EOpIndex(In)Direct
//                                          /           \
//                                      uniform          In
//
// produces:
//
//          EOpIndex(In)Direct
//            /        \
//        uniform    In*Pn + ... + I2*P2 + I1*P1
//
TIntermTyped *RewriteArrayOfArraySubscriptExpression(TCompiler *compiler,
                                                     TIntermBinary *node,
                                                     const UniformMap &uniformMap)
{ … }

// Traverser that takes:
//
//     uniform sampler/image/atomic_uint u[N][M]..
//
// and transforms it to:
//
//     uniform sampler/image/atomic_uint u[N * M * ..]
//
// MonomorphizeUnsupportedFunctions makes it impossible for this array to be partially
// subscripted, or passed as argument to a function unsubscripted.  This means that every encounter
// of this uniform can be expected to be fully subscripted.
//
class RewriteArrayOfArrayOfOpaqueUniformsTraverser : public TIntermTraverser
{ … };
}  // anonymous namespace

bool RewriteArrayOfArrayOfOpaqueUniforms(TCompiler *compiler,
                                         TIntermBlock *root,
                                         TSymbolTable *symbolTable)
{ … }
}  // namespace sh