// We need to scan for the following:
// 1. "invariant" keyword: This can occur in both - vertex and fragment shaders
// but only at the global scope.
// 2. "gl_PointCoord" built-in variable: This can only occur in fragment shader
// but inside any scope.
// 3. Call to a matrix constructor with another matrix as argument.
// (These constructors were reserved in GLSL version 1.10.)
// 4. Arrays as "out" function parameters.
// GLSL spec section 6.1.1: "When calling a function, expressions that do
// not evaluate to l-values cannot be passed to parameters declared as
// out or inout."
// GLSL 1.1 section 5.8: "Other binary or unary expressions,
// non-dereferenced arrays, function names, swizzles with repeated fields,
// and constants cannot be l-values."
// GLSL 1.2 relaxed the restriction on arrays, section 5.8: "Variables that
// are built-in types, entire structures or arrays... are all l-values."
//
TVersionGLSL::TVersionGLSL(sh::GLenum type, const TPragma &pragma, ShShaderOutput output)
: TIntermTraverser(true, false, false)
{
mVersion = ShaderOutputTypeToGLSLVersion(output);
if (pragma.stdgl.invariantAll)
{
ensureVersionIsAtLeast(GLSL_VERSION_120);
}
if (type == GL_COMPUTE_SHADER)
{
ensureVersionIsAtLeast(GLSL_VERSION_430);
}
}
void TVersionGLSL::visitSymbol(TIntermSymbol *node)
{
if (node->getSymbol() == "gl_PointCoord")
{
ensureVersionIsAtLeast(GLSL_VERSION_120);
}
}
void TVersionGLSL::visitSymbol(TIntermSymbol *node)
{
if (node->variable().symbolType() == SymbolType::BuiltIn &&
node->getName() == kGlPointCoordString)
{
ensureVersionIsAtLeast(GLSL_VERSION_120);
}
}
bool TVersionGLSL::visitDeclaration(Visit, TIntermDeclaration *node)
{
const TIntermSequence &sequence = *(node->getSequence());
if (sequence.front()->getAsTyped()->getType().isInvariant())
{
ensureVersionIsAtLeast(GLSL_VERSION_120);
}
return true;
}
bool TVersionGLSL::visitAggregate(Visit, TIntermAggregate *node)
{
if (node->getOp() == EOpConstruct && node->getType().isMatrix())
{
const TIntermSequence &sequence = *(node->getSequence());
if (sequence.size() == 1)
{
TIntermTyped *typed = sequence.front()->getAsTyped();
if (typed && typed->isMatrix())
{
ensureVersionIsAtLeast(GLSL_VERSION_120);
}
}
}
return true;
}
void TVersionGLSL::visitFunctionPrototype(TIntermFunctionPrototype *node)
{
size_t paramCount = node->getFunction()->getParamCount();
for (size_t i = 0; i < paramCount; ++i)
{
const TVariable *param = node->getFunction()->getParam(i);
const TType &type = param->getType();
if (type.isArray())
{
TQualifier qualifier = type.getQualifier();
if ((qualifier == EvqOut) || (qualifier == EvqInOut))
{
ensureVersionIsAtLeast(GLSL_VERSION_120);
break;
}
}
}
}
bool TVersionGLSL::visitAggregate(Visit, TIntermAggregate *node)
{
bool visitChildren = true;
switch (node->getOp())
{
case EOpDeclaration:
{
const TIntermSequence &sequence = *(node->getSequence());
if (sequence.front()->getAsTyped()->getType().isInvariant())
{
ensureVersionIsAtLeast(GLSL_VERSION_120);
}
break;
}
case EOpInvariantDeclaration:
ensureVersionIsAtLeast(GLSL_VERSION_120);
break;
case EOpParameters:
{
const TIntermSequence ¶ms = *(node->getSequence());
for (TIntermSequence::const_iterator iter = params.begin();
iter != params.end(); ++iter)
{
const TIntermTyped *param = (*iter)->getAsTyped();
if (param->isArray())
{
TQualifier qualifier = param->getQualifier();
if ((qualifier == EvqOut) || (qualifier == EvqInOut))
{
ensureVersionIsAtLeast(GLSL_VERSION_120);
break;
}
}
}
// Fully processed. No need to visit children.
visitChildren = false;
break;
}
case EOpConstructMat2:
case EOpConstructMat2x3:
case EOpConstructMat2x4:
case EOpConstructMat3x2:
case EOpConstructMat3:
case EOpConstructMat3x4:
case EOpConstructMat4x2:
case EOpConstructMat4x3:
case EOpConstructMat4:
{
const TIntermSequence &sequence = *(node->getSequence());
if (sequence.size() == 1)
{
TIntermTyped *typed = sequence.front()->getAsTyped();
if (typed && typed->isMatrix())
{
ensureVersionIsAtLeast(GLSL_VERSION_120);
}
}
break;
}
default:
break;
}
return visitChildren;
}
bool TVersionGLSL::visitInvariantDeclaration(Visit, TIntermInvariantDeclaration *node)
{
ensureVersionIsAtLeast(GLSL_VERSION_120);
return true;
}
