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//
// Copyright 2002 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.
//
#include "compiler/translator/TranslatorESSL.h"
#include "angle_gl.h"
#include "common/utilities.h"
#include "compiler/translator/BuiltInFunctionEmulatorGLSL.h"
#include "compiler/translator/OutputESSL.h"
#include "compiler/translator/tree_ops/RecordConstantPrecision.h"
namespace sh
{
TranslatorESSL::TranslatorESSL(sh::GLenum type, ShShaderSpec spec)
: TCompiler(type, spec, SH_ESSL_OUTPUT)
{}
void TranslatorESSL::initBuiltInFunctionEmulator(BuiltInFunctionEmulator *emu,
const ShCompileOptions &compileOptions)
{
if (compileOptions.emulateAtan2FloatFunction)
{
InitBuiltInAtanFunctionEmulatorForGLSLWorkarounds(emu);
}
}
bool TranslatorESSL::translate(TIntermBlock *root,
const ShCompileOptions &compileOptions,
PerformanceDiagnostics * /*perfDiagnostics*/)
{
TInfoSinkBase &sink = getInfoSink().obj;
int shaderVer = getShaderVersion(); // Frontend shader version.
if (hasPixelLocalStorageUniforms() &&
ShPixelLocalStorageTypeUsesImages(compileOptions.pls.type))
{
// The backend translator emits shader image code. Use a minimum version of 310.
shaderVer = std::max(shaderVer, 310);
}
if (shaderVer > 100)
{
sink << "#version " << shaderVer << " es\n";
}
// Write built-in extension behaviors.
writeExtensionBehavior(compileOptions);
// Write pragmas after extensions because some drivers consider pragmas
// like non-preprocessor tokens.
WritePragma(sink, compileOptions, getPragma());
if (!RecordConstantPrecision(this, root, &getSymbolTable()))
{
return false;
}
// Write emulated built-in functions if needed.
if (!getBuiltInFunctionEmulator().isOutputEmpty())
{
sink << "// BEGIN: Generated code for built-in function emulation\n\n";
if (getShaderType() == GL_FRAGMENT_SHADER)
{
sink << "#if defined(GL_FRAGMENT_PRECISION_HIGH)\n"
<< "#define emu_precision highp\n"
<< "#else\n"
<< "#define emu_precision mediump\n"
<< "#endif\n\n";
}
else
{
sink << "#define emu_precision highp\n";
}
getBuiltInFunctionEmulator().outputEmulatedFunctions(sink);
sink << "// END: Generated code for built-in function emulation\n\n";
}
if (getShaderType() == GL_FRAGMENT_SHADER)
{
EmitEarlyFragmentTestsGLSL(*this, sink);
}
if (getShaderType() == GL_COMPUTE_SHADER)
{
EmitWorkGroupSizeGLSL(*this, sink);
}
if (getShaderType() == GL_GEOMETRY_SHADER_EXT)
{
WriteGeometryShaderLayoutQualifiers(
sink, getGeometryShaderInputPrimitiveType(), getGeometryShaderInvocations(),
getGeometryShaderOutputPrimitiveType(), getGeometryShaderMaxVertices());
}
// Write translated shader.
TOutputESSL outputESSL(this, sink, compileOptions);
root->traverse(&outputESSL);
return true;
}
bool TranslatorESSL::shouldFlattenPragmaStdglInvariantAll()
{
// If following the spec to the letter, we should not flatten this pragma.
// However, the spec's wording means that the pragma applies only to outputs.
// This contradicts the spirit of using the pragma,
// because if the pragma is used in a vertex shader,
// the only way to be able to link it to a fragment shader
// is to manually qualify each of fragment shader's inputs as invariant.
// Which defeats the purpose of this pragma - temporarily make all varyings
// invariant for debugging.
// Thus, we should be non-conformant to spec's letter here and flatten.
return true;
}
void TranslatorESSL::writeExtensionBehavior(const ShCompileOptions &compileOptions)
{
TInfoSinkBase &sink = getInfoSink().obj;
const TExtensionBehavior &extBehavior = getExtensionBehavior();
for (TExtensionBehavior::const_iterator iter = extBehavior.begin(); iter != extBehavior.end();
++iter)
{
if (iter->second != EBhUndefined)
{
const bool isMultiview = (iter->first == TExtension::OVR_multiview) ||
(iter->first == TExtension::OVR_multiview2);
if (getResources().NV_shader_framebuffer_fetch &&
iter->first == TExtension::EXT_shader_framebuffer_fetch)
{
sink << "#extension GL_NV_shader_framebuffer_fetch : "
<< GetBehaviorString(iter->second) << "\n";
}
else if (getResources().NV_draw_buffers && iter->first == TExtension::EXT_draw_buffers)
{
sink << "#extension GL_NV_draw_buffers : " << GetBehaviorString(iter->second)
<< "\n";
}
else if (isMultiview)
{
// Only either OVR_multiview OR OVR_multiview2 should be emitted.
if ((iter->first != TExtension::OVR_multiview) ||
!IsExtensionEnabled(extBehavior, TExtension::OVR_multiview2))
{
EmitMultiviewGLSL(*this, compileOptions, iter->first, iter->second, sink);
}
}
else if (iter->first == TExtension::EXT_geometry_shader ||
iter->first == TExtension::OES_geometry_shader)
{
sink << "#ifdef GL_EXT_geometry_shader\n"
<< "#extension GL_EXT_geometry_shader : " << GetBehaviorString(iter->second)
<< "\n"
<< "#elif defined GL_OES_geometry_shader\n"
<< "#extension GL_OES_geometry_shader : " << GetBehaviorString(iter->second)
<< "\n";
if (iter->second == EBhRequire)
{
sink << "#else\n"
<< "#error \"No geometry shader extensions available.\" // Only generate "
"this if the extension is \"required\"\n";
}
sink << "#endif\n";
}
else if (iter->first == TExtension::ANGLE_multi_draw)
{
// Don't emit anything. This extension is emulated
ASSERT(compileOptions.emulateGLDrawID);
continue;
}
else if (iter->first == TExtension::ANGLE_base_vertex_base_instance_shader_builtin)
{
// Don't emit anything. This extension is emulated
ASSERT(compileOptions.emulateGLBaseVertexBaseInstance);
continue;
}
else if (iter->first == TExtension::ANGLE_shader_pixel_local_storage)
{
// TODO(anglebug.com/7279): future impl that uses EXT_shader_pixel_local_storage.
if (compileOptions.pls.type == ShPixelLocalStorageType::FramebufferFetch)
{
// Just enable the extension. Appropriate warnings will be generated by the
// frontend compiler for GL_ANGLE_shader_pixel_local_storage, if desired.
sink << "#extension GL_EXT_shader_framebuffer_fetch : enable\n";
}
continue;
}
else if (iter->first == TExtension::EXT_shader_framebuffer_fetch)
{
sink << "#extension GL_EXT_shader_framebuffer_fetch : "
<< GetBehaviorString(iter->second) << "\n";
continue;
}
else if (iter->first == TExtension::EXT_shader_framebuffer_fetch_non_coherent)
{
sink << "#extension GL_EXT_shader_framebuffer_fetch_non_coherent : "
<< GetBehaviorString(iter->second) << "\n";
continue;
}
else if (iter->first == TExtension::WEBGL_video_texture)
{
// Don't emit anything. This extension is emulated
// TODO(crbug.com/776222): support external image.
continue;
}
else
{
sink << "#extension " << GetExtensionNameString(iter->first) << " : "
<< GetBehaviorString(iter->second) << "\n";
}
}
}
}
} // namespace sh
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