gecko-dev/dom/canvas/WebGLShaderValidator.cpp
2016-07-25 20:01:09 -07:00

584 lines
19 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "WebGLShaderValidator.h"
#include "angle/ShaderLang.h"
#include "gfxPrefs.h"
#include "GLContext.h"
#include "mozilla/Preferences.h"
#include "MurmurHash3.h"
#include "nsPrintfCString.h"
#include <string>
#include <vector>
#include "WebGLContext.h"
namespace mozilla {
namespace webgl {
uint64_t
IdentifierHashFunc(const char* name, size_t len)
{
// NB: we use the x86 function everywhere, even though it's suboptimal perf
// on x64. They return different results; not sure if that's a requirement.
uint64_t hash[2];
MurmurHash3_x86_128(name, len, 0, hash);
return hash[0];
}
static int
ChooseValidatorCompileOptions(const ShBuiltInResources& resources,
const mozilla::gl::GLContext* gl)
{
int options = SH_VARIABLES |
SH_ENFORCE_PACKING_RESTRICTIONS |
SH_INIT_VARYINGS_WITHOUT_STATIC_USE |
SH_OBJECT_CODE |
SH_LIMIT_CALL_STACK_DEPTH |
SH_INIT_GL_POSITION;
if (resources.MaxExpressionComplexity > 0) {
options |= SH_LIMIT_EXPRESSION_COMPLEXITY;
}
// Sampler arrays indexed with non-constant expressions are forbidden in
// GLSL 1.30 and later.
// ESSL 3 requires constant-integral-expressions for this as well.
// Just do it universally.
options |= SH_UNROLL_FOR_LOOP_WITH_SAMPLER_ARRAY_INDEX;
if (gfxPrefs::WebGLAllANGLEOptions()) {
return options |
SH_VALIDATE_LOOP_INDEXING |
SH_UNROLL_FOR_LOOP_WITH_INTEGER_INDEX |
SH_UNROLL_FOR_LOOP_WITH_SAMPLER_ARRAY_INDEX |
SH_EMULATE_BUILT_IN_FUNCTIONS |
SH_CLAMP_INDIRECT_ARRAY_BOUNDS |
SH_UNFOLD_SHORT_CIRCUIT |
SH_SCALARIZE_VEC_AND_MAT_CONSTRUCTOR_ARGS |
SH_REGENERATE_STRUCT_NAMES;
}
#ifndef XP_MACOSX
// We want to do this everywhere, but to do this on Mac, we need
// to do it only on Mac OSX > 10.6 as this causes the shader
// compiler in 10.6 to crash
options |= SH_CLAMP_INDIRECT_ARRAY_BOUNDS;
#endif
#ifdef XP_MACOSX
if (gl->WorkAroundDriverBugs()) {
// Work around https://bugs.webkit.org/show_bug.cgi?id=124684,
// https://chromium.googlesource.com/angle/angle/+/5e70cf9d0b1bb
options |= SH_UNFOLD_SHORT_CIRCUIT;
// Work around bug 665578 and bug 769810
if (gl->Vendor() == gl::GLVendor::ATI) {
options |= SH_EMULATE_BUILT_IN_FUNCTIONS;
}
// Work around bug 735560
if (gl->Vendor() == gl::GLVendor::Intel) {
options |= SH_EMULATE_BUILT_IN_FUNCTIONS;
}
// Work around that Mac drivers handle struct scopes incorrectly.
options |= SH_REGENERATE_STRUCT_NAMES;
}
#endif
return options;
}
} // namespace webgl
////////////////////////////////////////
static ShShaderOutput
ShaderOutput(gl::GLContext* gl)
{
if (gl->IsGLES()) {
return SH_ESSL_OUTPUT;
} else {
uint32_t version = gl->ShadingLanguageVersion();
switch (version) {
case 100: return SH_GLSL_COMPATIBILITY_OUTPUT;
case 120: return SH_GLSL_COMPATIBILITY_OUTPUT;
case 130: return SH_GLSL_130_OUTPUT;
case 140: return SH_GLSL_140_OUTPUT;
case 150: return SH_GLSL_150_CORE_OUTPUT;
case 330: return SH_GLSL_330_CORE_OUTPUT;
case 400: return SH_GLSL_400_CORE_OUTPUT;
case 410: return SH_GLSL_410_CORE_OUTPUT;
case 420: return SH_GLSL_420_CORE_OUTPUT;
case 430: return SH_GLSL_430_CORE_OUTPUT;
case 440: return SH_GLSL_440_CORE_OUTPUT;
case 450: return SH_GLSL_450_CORE_OUTPUT;
default:
MOZ_CRASH("GFX: Unexpected GLSL version.");
}
}
return SH_GLSL_COMPATIBILITY_OUTPUT;
}
webgl::ShaderValidator*
WebGLContext::CreateShaderValidator(GLenum shaderType) const
{
if (mBypassShaderValidation)
return nullptr;
const auto spec = (IsWebGL2() ? SH_WEBGL2_SPEC : SH_WEBGL_SPEC);
const auto outputLanguage = ShaderOutput(gl);
ShBuiltInResources resources;
memset(&resources, 0, sizeof(resources));
ShInitBuiltInResources(&resources);
resources.HashFunction = webgl::IdentifierHashFunc;
resources.MaxVertexAttribs = mGLMaxVertexAttribs;
resources.MaxVertexUniformVectors = mGLMaxVertexUniformVectors;
resources.MaxVaryingVectors = mGLMaxVaryingVectors;
resources.MaxVertexTextureImageUnits = mGLMaxVertexTextureImageUnits;
resources.MaxCombinedTextureImageUnits = mGLMaxTextureUnits;
resources.MaxTextureImageUnits = mGLMaxTextureImageUnits;
resources.MaxFragmentUniformVectors = mGLMaxFragmentUniformVectors;
const bool hasMRTs = (IsWebGL2() ||
IsExtensionEnabled(WebGLExtensionID::WEBGL_draw_buffers));
resources.MaxDrawBuffers = (hasMRTs ? mGLMaxDrawBuffers : 1);
if (IsExtensionEnabled(WebGLExtensionID::EXT_frag_depth))
resources.EXT_frag_depth = 1;
if (IsExtensionEnabled(WebGLExtensionID::OES_standard_derivatives))
resources.OES_standard_derivatives = 1;
if (IsExtensionEnabled(WebGLExtensionID::WEBGL_draw_buffers))
resources.EXT_draw_buffers = 1;
if (IsExtensionEnabled(WebGLExtensionID::EXT_shader_texture_lod))
resources.EXT_shader_texture_lod = 1;
// Tell ANGLE to allow highp in frag shaders. (unless disabled)
// If underlying GLES doesn't have highp in frag shaders, it should complain anyways.
resources.FragmentPrecisionHigh = mDisableFragHighP ? 0 : 1;
if (gl->WorkAroundDriverBugs()) {
#ifdef XP_MACOSX
if (gl->Vendor() == gl::GLVendor::NVIDIA) {
// Work around bug 890432
resources.MaxExpressionComplexity = 1000;
}
#endif
}
int compileOptions = webgl::ChooseValidatorCompileOptions(resources, gl);
return webgl::ShaderValidator::Create(shaderType, spec, outputLanguage, resources,
compileOptions);
}
////////////////////////////////////////
namespace webgl {
/*static*/ ShaderValidator*
ShaderValidator::Create(GLenum shaderType, ShShaderSpec spec,
ShShaderOutput outputLanguage,
const ShBuiltInResources& resources, int compileOptions)
{
ShHandle handle = ShConstructCompiler(shaderType, spec, outputLanguage, &resources);
if (!handle)
return nullptr;
return new ShaderValidator(handle, compileOptions, resources.MaxVaryingVectors);
}
ShaderValidator::~ShaderValidator()
{
ShDestruct(mHandle);
}
bool
ShaderValidator::ValidateAndTranslate(const char* source)
{
MOZ_ASSERT(!mHasRun);
mHasRun = true;
const char* const parts[] = {
source
};
return ShCompile(mHandle, parts, ArrayLength(parts), mCompileOptions);
}
void
ShaderValidator::GetInfoLog(nsACString* out) const
{
MOZ_ASSERT(mHasRun);
const std::string &log = ShGetInfoLog(mHandle);
out->Assign(log.data(), log.length());
}
void
ShaderValidator::GetOutput(nsACString* out) const
{
MOZ_ASSERT(mHasRun);
const std::string &output = ShGetObjectCode(mHandle);
out->Assign(output.data(), output.length());
}
template<size_t N>
static bool
StartsWith(const std::string& haystack, const char (&needle)[N])
{
return haystack.compare(0, N - 1, needle) == 0;
}
bool
ShaderValidator::CanLinkTo(const ShaderValidator* prev, nsCString* const out_log) const
{
if (!prev) {
nsPrintfCString error("Passed in NULL prev ShaderValidator.");
*out_log = error;
return false;
}
const auto shaderVersion = ShGetShaderVersion(mHandle);
if (ShGetShaderVersion(prev->mHandle) != shaderVersion) {
nsPrintfCString error("Vertex shader version %d does not match"
" fragment shader version %d.",
ShGetShaderVersion(prev->mHandle),
ShGetShaderVersion(mHandle));
*out_log = error;
return false;
}
{
const std::vector<sh::Uniform>* vertPtr = ShGetUniforms(prev->mHandle);
const std::vector<sh::Uniform>* fragPtr = ShGetUniforms(mHandle);
if (!vertPtr || !fragPtr) {
nsPrintfCString error("Could not create uniform list.");
*out_log = error;
return false;
}
for (auto itrFrag = fragPtr->begin(); itrFrag != fragPtr->end(); ++itrFrag) {
for (auto itrVert = vertPtr->begin(); itrVert != vertPtr->end(); ++itrVert) {
if (itrVert->name != itrFrag->name)
continue;
if (!itrVert->isSameUniformAtLinkTime(*itrFrag)) {
nsPrintfCString error("Uniform `%s`is not linkable between"
" attached shaders.",
itrFrag->name.c_str());
*out_log = error;
return false;
}
break;
}
}
}
const auto& vertVaryings = ShGetVaryings(prev->mHandle);
const auto& fragVaryings = ShGetVaryings(mHandle);
if (!vertVaryings || !fragVaryings) {
nsPrintfCString error("Could not create varying list.");
*out_log = error;
return false;
}
{
std::vector<ShVariableInfo> staticUseVaryingList;
for (const auto& fragVarying : *fragVaryings) {
const ShVariableInfo varInfo = { fragVarying.type,
(int)fragVarying.elementCount() };
static const char prefix[] = "gl_";
if (StartsWith(fragVarying.name, prefix)) {
if (fragVarying.staticUse) {
staticUseVaryingList.push_back(varInfo);
}
continue;
}
bool definedInVertShader = false;
bool staticVertUse = false;
for (const auto& vertVarying : *vertVaryings) {
if (vertVarying.name != fragVarying.name)
continue;
if (!vertVarying.isSameVaryingAtLinkTime(fragVarying, shaderVersion)) {
nsPrintfCString error("Varying `%s`is not linkable between"
" attached shaders.",
fragVarying.name.c_str());
*out_log = error;
return false;
}
definedInVertShader = true;
staticVertUse = vertVarying.staticUse;
break;
}
if (!definedInVertShader && fragVarying.staticUse) {
nsPrintfCString error("Varying `%s` has static-use in the frag"
" shader, but is undeclared in the vert"
" shader.", fragVarying.name.c_str());
*out_log = error;
return false;
}
if (staticVertUse && fragVarying.staticUse) {
staticUseVaryingList.push_back(varInfo);
}
}
if (!ShCheckVariablesWithinPackingLimits(mMaxVaryingVectors,
staticUseVaryingList.data(),
staticUseVaryingList.size()))
{
*out_log = "Statically used varyings do not fit within packing limits. (see"
" GLSL ES Specification 1.0.17, p111)";
return false;
}
}
if (shaderVersion == 100) {
// Enforce ESSL1 invariant linking rules.
bool isInvariant_Position = false;
bool isInvariant_PointSize = false;
bool isInvariant_FragCoord = false;
bool isInvariant_PointCoord = false;
for (const auto& varying : *vertVaryings) {
if (varying.name == "gl_Position") {
isInvariant_Position = varying.isInvariant;
} else if (varying.name == "gl_PointSize") {
isInvariant_PointSize = varying.isInvariant;
}
}
for (const auto& varying : *fragVaryings) {
if (varying.name == "gl_FragCoord") {
isInvariant_FragCoord = varying.isInvariant;
} else if (varying.name == "gl_PointCoord") {
isInvariant_PointCoord = varying.isInvariant;
}
}
////
const auto fnCanBuiltInsLink = [](bool vertIsInvariant, bool fragIsInvariant) {
if (vertIsInvariant)
return true;
return !fragIsInvariant;
};
if (!fnCanBuiltInsLink(isInvariant_Position, isInvariant_FragCoord)) {
*out_log = "gl_Position must be invariant if gl_FragCoord is. (see GLSL ES"
" Specification 1.0.17, p39)";
return false;
}
if (!fnCanBuiltInsLink(isInvariant_PointSize, isInvariant_PointCoord)) {
*out_log = "gl_PointSize must be invariant if gl_PointCoord is. (see GLSL ES"
" Specification 1.0.17, p39)";
return false;
}
}
return true;
}
size_t
ShaderValidator::CalcNumSamplerUniforms() const
{
size_t accum = 0;
const std::vector<sh::Uniform>& uniforms = *ShGetUniforms(mHandle);
for (auto itr = uniforms.begin(); itr != uniforms.end(); ++itr) {
GLenum type = itr->type;
if (type == LOCAL_GL_SAMPLER_2D ||
type == LOCAL_GL_SAMPLER_CUBE)
{
accum += itr->arraySize;
}
}
return accum;
}
size_t
ShaderValidator::NumAttributes() const
{
return ShGetAttributes(mHandle)->size();
}
// Attribs cannot be structs or arrays, and neither can vertex inputs in ES3.
// Therefore, attrib names are always simple.
bool
ShaderValidator::FindAttribUserNameByMappedName(const std::string& mappedName,
const std::string** const out_userName) const
{
const std::vector<sh::Attribute>& attribs = *ShGetAttributes(mHandle);
for (auto itr = attribs.begin(); itr != attribs.end(); ++itr) {
if (itr->mappedName == mappedName) {
*out_userName = &(itr->name);
return true;
}
}
return false;
}
bool
ShaderValidator::FindAttribMappedNameByUserName(const std::string& userName,
const std::string** const out_mappedName) const
{
const std::vector<sh::Attribute>& attribs = *ShGetAttributes(mHandle);
for (auto itr = attribs.begin(); itr != attribs.end(); ++itr) {
if (itr->name == userName) {
*out_mappedName = &(itr->mappedName);
return true;
}
}
return false;
}
bool
ShaderValidator::FindVaryingByMappedName(const std::string& mappedName,
std::string* const out_userName,
bool* const out_isArray) const
{
const std::vector<sh::Varying>& varyings = *ShGetVaryings(mHandle);
for (auto itr = varyings.begin(); itr != varyings.end(); ++itr) {
const sh::ShaderVariable* found;
if (!itr->findInfoByMappedName(mappedName, &found, out_userName))
continue;
*out_isArray = found->isArray();
return true;
}
return false;
}
bool
ShaderValidator::FindVaryingMappedNameByUserName(const std::string& userName,
const std::string** const out_mappedName) const
{
const std::vector<sh::Varying>& attribs = *ShGetVaryings(mHandle);
for (auto itr = attribs.begin(); itr != attribs.end(); ++itr) {
if (itr->name == userName) {
*out_mappedName = &(itr->mappedName);
return true;
}
}
return false;
}
// This must handle names like "foo.bar[0]".
bool
ShaderValidator::FindUniformByMappedName(const std::string& mappedName,
std::string* const out_userName,
bool* const out_isArray) const
{
const std::vector<sh::Uniform>& uniforms = *ShGetUniforms(mHandle);
for (auto itr = uniforms.begin(); itr != uniforms.end(); ++itr) {
const sh::ShaderVariable* found;
if (!itr->findInfoByMappedName(mappedName, &found, out_userName))
continue;
*out_isArray = found->isArray();
return true;
}
const size_t dotPos = mappedName.find(".");
const std::vector<sh::InterfaceBlock>& interfaces = *ShGetInterfaceBlocks(mHandle);
for (const auto& interface : interfaces) {
std::string mappedFieldName;
const bool hasInstanceName = !interface.instanceName.empty();
// If the InterfaceBlock has an instanceName, all variables defined
// within the block are qualified with the block name, as opposed
// to being placed in the global scope.
if (hasInstanceName) {
// If mappedName has no block name prefix, skip
if (std::string::npos == dotPos)
continue;
// If mappedName has a block name prefix that doesn't match, skip
const std::string mappedInterfaceBlockName = mappedName.substr(0, dotPos);
if (interface.mappedName != mappedInterfaceBlockName)
continue;
mappedFieldName = mappedName.substr(dotPos + 1);
} else {
mappedFieldName = mappedName;
}
for (const auto& field : interface.fields) {
const sh::ShaderVariable* found;
if (!field.findInfoByMappedName(mappedFieldName, &found, out_userName))
continue;
if (hasInstanceName) {
// Prepend the user name of the interface that matched
*out_userName = interface.name + "." + *out_userName;
}
*out_isArray = found->isArray();
return true;
}
}
return false;
}
bool
ShaderValidator::FindUniformBlockByMappedName(const std::string& mappedName,
std::string* const out_userName) const
{
const std::vector<sh::InterfaceBlock>& interfaces = *ShGetInterfaceBlocks(mHandle);
for (const auto& interface : interfaces) {
if (mappedName == interface.mappedName) {
*out_userName = interface.name;
return true;
}
}
return false;
}
void
ShaderValidator::EnumerateFragOutputs(std::map<nsCString, const nsCString> &out_FragOutputs) const
{
const auto* fragOutputs = ShGetOutputVariables(mHandle);
if (fragOutputs) {
for (const auto& fragOutput : *fragOutputs) {
out_FragOutputs.insert({nsCString(fragOutput.name.c_str()),
nsCString(fragOutput.mappedName.c_str())});
}
}
}
} // namespace webgl
} // namespace mozilla