Hash :
5d91dda9
Author :
Date :
2015-06-18T15:47:46
Remove dynamic indexing of matrices and vectors in HLSL
Re-re-relanding after clang warning fix.
Re-re-landing with fix to setting qualifiers on generated nodes. The
previous version failed when a uniform was indexed, because it would
set the uniform qualifier on some of the generated nodes and that
interfered with the operation of UniformsHLSL.
Re-landing after fixing D3D9 specific issues.
HLSL doesn't support dynamic indexing of matrices and vectors, so replace
that with helper functions that unroll dynamic indexing into switch/case
and static indexing.
Both the indexed vector/matrix expression and the index may have side
effects, and these will be evaluated correctly. If necessary, index
expressions that have side effects will be written to a temporary
variable that will replace the index.
Besides dEQP tests, this change is tested by a WebGL 2 conformance test.
In the case that a dynamic index is out-of-range, the base ESSL 3.00 spec
allows undefined behavior. KHR_robust_buffer_access_behavior adds the
requirement that program termination should not occur and that
out-of-range reads must return either a value from the active program's
memory or zero, and out-of-range writes should only affect the active
program's memory or do nothing. This patch clamps out-of-range indices so
that either the first or last item of the matrix/vector is accessed.
The code is not transformed in case the it fits within the limited subset
of ESSL 1.00 given in Appendix A of the spec. If the code isn't within
the restricted subset, even ESSL 1.00 shaders may require this
workaround.
BUG=angleproject:1116
TEST=dEQP-GLES3.functional.shaders.indexing.* (all pass after change)
WebGL 2 conformance tests (glsl3/vector-dynamic-indexing.html)
Change-Id: I9f6d7c7ecda8ac4dc3c30b39e15a9a0b5381c5a8
Reviewed-on: https://chromium-review.googlesource.com/310010
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Tested-by: Geoff Lang <geofflang@chromium.org>
//
// Copyright (c) 2002-2015 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.
//
// RemoveDynamicIndexing is an AST traverser to remove dynamic indexing of vectors and matrices,
// replacing them with calls to functions that choose which component to return or write.
//
#ifndef COMPILER_TRANSLATOR_REMOVEDYNAMICINDEXING_H_
#define COMPILER_TRANSLATOR_REMOVEDYNAMICINDEXING_H_
class TIntermNode;
class TSymbolTable;
void RemoveDynamicIndexing(TIntermNode *root,
unsigned int *temporaryIndex,
const TSymbolTable &symbolTable,
int shaderVersion);
#endif // COMPILER_TRANSLATOR_REMOVEDYNAMICINDEXING_H_