SkSL::ConstructorCompound Class Reference

#include <SkSLConstructorCompound.h>

Inheritance diagram for SkSL::ConstructorCompound:

Public Member Functions
	ConstructorCompound (Position pos, const Type &type, ExpressionArray args)
std::unique_ptr< Expression >	clone (Position pos) const override
Public Member Functions inherited from SkSL::MultiArgumentConstructor
	MultiArgumentConstructor (Position pos, Kind kind, const Type *type, ExpressionArray arguments)
ExpressionArray &	arguments ()
const ExpressionArray &	arguments () const
SkSpan< std::unique_ptr< Expression > >	argumentSpan () final
SkSpan< const std::unique_ptr< Expression > >	argumentSpan () const final
Public Member Functions inherited from SkSL::AnyConstructor
	AnyConstructor (Position pos, Kind kind, const Type *type)
virtual SkSpan< std::unique_ptr< Expression > >	argumentSpan ()=0
virtual SkSpan< const std::unique_ptr< Expression > >	argumentSpan () const =0
std::string	description (OperatorPrecedence) const override
const Type &	componentType () const
bool	supportsConstantValues () const override
std::optional< double >	getConstantValue (int n) const override
ComparisonResult	compareConstant (const Expression &other) const override
Public Member Functions inherited from SkSL::Expression
	Expression (Position pos, Kind kind, const Type *type)
Kind	kind () const
const Type &	type () const
bool	isAnyConstructor () const
bool	isIntLiteral () const
bool	isFloatLiteral () const
bool	isBoolLiteral () const
AnyConstructor &	asAnyConstructor ()
const AnyConstructor &	asAnyConstructor () const
bool	isIncomplete (const Context &context) const
virtual ComparisonResult	compareConstant (const Expression &other) const
CoercionCost	coercionCost (const Type &target) const
virtual bool	supportsConstantValues () const
virtual std::optional< double >	getConstantValue (int n) const
virtual std::unique_ptr< Expression >	clone (Position pos) const =0
std::unique_ptr< Expression >	clone () const
std::string	description () const final
virtual std::string	description (OperatorPrecedence parentPrecedence) const =0
Public Member Functions inherited from SkSL::IRNode
virtual	~IRNode ()
virtual std::string	description () const =0
	IRNode (const IRNode &)=delete
IRNode &	operator= (const IRNode &)=delete
Position	position () const
void	setPosition (Position p)
template<typename T >
bool	is () const
template<typename T >
const T &	as () const
template<typename T >
T &	as ()

Static Public Member Functions
static std::unique_ptr< Expression >	Make (const Context &context, Position pos, const Type &type, ExpressionArray args)
static std::unique_ptr< Expression >	MakeFromConstants (const Context &context, Position pos, const Type &type, const double values[])
Static Public Member Functions inherited from SkSL::Poolable
static void *	operator new (const size_t size)
static void	operator delete (void *ptr)

Static Public Attributes
static constexpr Kind	kIRNodeKind = Kind::kConstructorCompound

Additional Inherited Members
Public Types inherited from SkSL::Expression
enum class	ComparisonResult { kUnknown = -1 , kNotEqual , kEqual }
using	Kind = ExpressionKind
Public Attributes inherited from SkSL::IRNode
Position	fPosition
Protected Member Functions inherited from SkSL::IRNode
	IRNode (Position position, int kind)
Protected Attributes inherited from SkSL::IRNode
int	fKind

Detailed Description

Represents a vector or matrix that is composed from other expressions, such as half3(pos.xy, 1) or mat3(a.xyz, b.xyz, 0, 0, 1)

These can contain a mix of scalars and aggregates. The total number of scalar values inside the constructor must always match the type's slot count. (e.g. pos.xy consumes two slots.) The inner values must have the same component type as the vector/matrix.

Definition at line 33 of file SkSLConstructorCompound.h.

Constructor & Destructor Documentation

ConstructorCompound()

SkSL::ConstructorCompound::ConstructorCompound ( Position  pos, const Type &  type, ExpressionArray  args  )

inline

Definition at line 37 of file SkSLConstructorCompound.h.

            : INHERITED(pos, kIRNodeKind, &type, std::move(args)) {}

Member Function Documentation

clone()

std::unique_ptr< Expression > SkSL::ConstructorCompound::clone ( Position  pos ) const

inlineoverridevirtual

Implements SkSL::Expression.

Definition at line 50 of file SkSLConstructorCompound.h.

                                                                 {
        return std::make_unique<ConstructorCompound>(pos, this->type(), this->arguments().clone());
    }

Make()

std::unique_ptr< Expression > SkSL::ConstructorCompound::Make ( const Context &  context, Position  pos, const Type &  type, ExpressionArray  args  )

static

Definition at line 78 of file SkSLConstructorCompound.cpp.

                                                                            {
    SkASSERT(type.isAllowedInES2(context));
 
    // All the arguments must have matching component type.
    SkASSERT(std::all_of(args.begin(), args.end(), [&](const std::unique_ptr<Expression>& arg) {
        const Type& argType = arg->type();
        return (argType.isScalar() || argType.isVector() || argType.isMatrix()) &&
               (argType.componentType().matches(type.componentType()));
    }));
 
    // The slot count of the combined argument list must match the composite type's slot count.
    SkASSERT(type.slotCount() ==
             std::accumulate(args.begin(), args.end(), /*initial value*/ (size_t)0,
                             [](size_t n, const std::unique_ptr<Expression>& arg) {
                                 return n + arg->type().slotCount();
                             }));
    // No-op compound constructors (containing a single argument of the same type) are eliminated.
    // (Even though this is a "compound constructor," we let scalars pass through here; it's
    // harmless to allow and simplifies call sites which need to narrow a vector and may sometimes
    // end up with a scalar.)
    if (args.size() == 1 && is_safe_to_eliminate(type, *args.front())) {
        args.front()->fPosition = pos;
        return std::move(args.front());
    }
    // Beyond this point, the type must be a vector or matrix.
    SkASSERT(type.isVector() || type.isMatrix());
 
    if (context.fConfig->fSettings.fOptimize) {
        // Find ConstructorCompounds embedded inside other ConstructorCompounds and flatten them.
        //   -  float4(float2(1, 2), 3, 4)                -->  float4(1, 2, 3, 4)
        //   -  float4(w, float3(sin(x), cos(y), tan(z))) -->  float4(w, sin(x), cos(y), tan(z))
        //   -  mat2(float2(a, b), float2(c, d))          -->  mat2(a, b, c, d)
 
        // See how many fields we would have if composite constructors were flattened out.
        int fields = 0;
        for (const std::unique_ptr<Expression>& arg : args) {
            fields += arg->is<ConstructorCompound>()
                              ? arg->as<ConstructorCompound>().arguments().size()
                              : 1;
        }
 
        // If we added up more fields than we're starting with, we found at least one input that can
        // be flattened out.
        if (fields > args.size()) {
            ExpressionArray flattened;
            flattened.reserve_exact(fields);
            for (std::unique_ptr<Expression>& arg : args) {
                // For non-ConstructorCompound fields, move them over as-is.
                if (!arg->is<ConstructorCompound>()) {
                    flattened.push_back(std::move(arg));
                    continue;
                }
                // For ConstructorCompound fields, move over their inner arguments individually.
                ConstructorCompound& compositeCtor = arg->as<ConstructorCompound>();
                for (std::unique_ptr<Expression>& innerArg : compositeCtor.arguments()) {
                    flattened.push_back(std::move(innerArg));
                }
            }
            args = std::move(flattened);
        }
    }
 
    // Replace constant variables with their corresponding values, so `float2(one, two)` can
    // compile down to `float2(1.0, 2.0)` (the latter is a compile-time constant).
    for (std::unique_ptr<Expression>& arg : args) {
        arg = ConstantFolder::MakeConstantValueForVariable(pos, std::move(arg));
    }
 
    if (context.fConfig->fSettings.fOptimize) {
        // Reduce compound constructors to splats where possible.
        if (const Expression* splat = make_splat_from_arguments(type, args)) {
            return ConstructorSplat::Make(context, pos, type, splat->clone());
        }
    }
 
    return std::make_unique<ConstructorCompound>(pos, type, std::move(args));
}

MakeFromConstants()

std::unique_ptr< Expression > SkSL::ConstructorCompound::MakeFromConstants ( const Context &  context, Position  pos, const Type &  type, const double  values[]  )

static

Definition at line 159 of file SkSLConstructorCompound.cpp.

                                                                                         {
    int numSlots = returnType.slotCount();
    ExpressionArray array;
    array.reserve_exact(numSlots);
    for (int index = 0; index < numSlots; ++index) {
        array.push_back(Literal::Make(pos, value[index], &returnType.componentType()));
    }
    return ConstructorCompound::Make(context, pos, returnType, std::move(array));
}

Member Data Documentation

kIRNodeKind

constexpr Kind SkSL::ConstructorCompound::kIRNodeKind = Kind::kConstructorCompound

inlinestaticconstexpr

Definition at line 35 of file SkSLConstructorCompound.h.

---

The documentation for this class was generated from the following files:

• third_party/skia/src/sksl/ir/SkSLConstructorCompound.h
• third_party/skia/src/sksl/ir/SkSLConstructorCompound.cpp