src/sksl/ir/SkSLFunctionDeclaration.cpp - platform/external/skia - Gitiles

 /*
  * Copyright 2021 Google LLC.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #include "src/sksl/ir/SkSLFunctionDeclaration.h"

 #include "src/sksl/SkSLCompiler.h"
 #include "src/sksl/SkSLIRGenerator.h"
 #include "src/sksl/ir/SkSLUnresolvedFunction.h"

 namespace SkSL {

 static bool check_modifiers(const Context& context, int offset, const Modifiers& modifiers) {
     IRGenerator::CheckModifiers(
             context,
             offset,
             modifiers,
             Modifiers::kHasSideEffects_Flag | Modifiers::kInline_Flag | Modifiers::kNoInline_Flag,
             /*permittedLayoutFlags=*/0);
     if ((modifiers.fFlags & Modifiers::kInline_Flag) &&
         (modifiers.fFlags & Modifiers::kNoInline_Flag)) {
         context.fErrors.error(offset, "functions cannot be both 'inline' and 'noinline'");
         return false;
     }
     return true;
 }

 static bool check_return_type(const Context& context, int offset, const Type& returnType,
                               bool isBuiltin) {
     ErrorReporter& errors = context.fErrors;
     if (returnType.isArray()) {
         errors.error(offset, "functions may not return type '" + returnType.displayName() + "'");
         return false;
     }
     if (context.fConfig->strictES2Mode() && returnType.isOrContainsArray()) {
         errors.error(offset, "functions may not return structs containing arrays");
         return false;
     }
     if (!isBuiltin && !returnType.isVoid() && returnType.componentType().isOpaque()) {
         errors.error(offset, "functions may not return opaque type '" + returnType.displayName() +
                              "'");
         return false;
     }
     return true;
 }

 static bool check_parameters(const Context& context, ModifiersPool& modifiersPool,
                              std::vector<std::unique_ptr<Variable>>& parameters, bool isMain,
                              bool isBuiltin) {
     auto typeIsValidForColor = [&](const Type& type) {
         return type == *context.fTypes.fHalf4 || type == *context.fTypes.fFloat4;
     };

     // Check modifiers on each function parameter.
     for (auto& param : parameters) {
         IRGenerator::CheckModifiers(context, param->fOffset, param->modifiers(),
                                     Modifiers::kConst_Flag | Modifiers::kIn_Flag |
                                     Modifiers::kOut_Flag, /*permittedLayoutFlags=*/0);
         const Type& type = param->type();
         // Only the (builtin) declarations of 'sample' are allowed to have shader/colorFilter or FP
         // parameters. You can pass other opaque types to functions safely; this restriction is
         // specific to "child" objects.
         if ((type.isEffectChild() || type.isFragmentProcessor()) && !isBuiltin) {
             context.fErrors.error(param->fOffset, "parameters of type '" + type.displayName() +
                                                   "' not allowed");
             return false;
         }

         Modifiers m = param->modifiers();
         ProgramKind kind = context.fConfig->fKind;
         if (isMain && (kind == ProgramKind::kRuntimeColorFilter ||
                        kind == ProgramKind::kRuntimeShader ||
                        kind == ProgramKind::kFragmentProcessor)) {
             // We verify that the signature is fully correct later. For now, if this is an .fp or
             // runtime effect of any flavor, a float2 param is supposed to be the coords, and
             // a half4/float parameter is supposed to be the input color:
             if (type == *context.fTypes.fFloat2) {
                 m.fLayout.fBuiltin = SK_MAIN_COORDS_BUILTIN;
             } else if(typeIsValidForColor(type)) {
                 m.fLayout.fBuiltin = SK_INPUT_COLOR_BUILTIN;
             }
             if (m.fLayout.fBuiltin) {
                 param->setModifiers(modifiersPool.add(m));
             }
         }
         if (isMain && (kind == ProgramKind::kFragment)) {
             // For testing purposes, we have .sksl inputs that are treated as both runtime effects
             // and fragment shaders. To make that work, fragment shaders are allowed to have a
             // coords parameter. We turn it into sk_FragCoord.
             if (type == *context.fTypes.fFloat2) {
                 m.fLayout.fBuiltin = SK_FRAGCOORD_BUILTIN;
                 param->setModifiers(modifiersPool.add(m));
             }
         }
     }
     return true;
 }

 static bool check_main_signature(const Context& context, int offset, const Type& returnType,
                                  std::vector<std::unique_ptr<Variable>>& parameters,
                                  bool isBuiltin) {
     ErrorReporter& errors = context.fErrors;
     ProgramKind kind = context.fConfig->fKind;

     auto typeIsValidForColor = [&](const Type& type) {
         return type == *context.fTypes.fHalf4 || type == *context.fTypes.fFloat4;
     };

     auto paramIsCoords = [&](int idx) {
         const Variable& p = *parameters[idx];
         return p.type() == *context.fTypes.fFloat2 &&
                p.modifiers().fFlags == 0 &&
                p.modifiers().fLayout.fBuiltin == (kind == ProgramKind::kFragment
                                                            ? SK_FRAGCOORD_BUILTIN
                                                            : SK_MAIN_COORDS_BUILTIN);
     };

     auto paramIsInputColor = [&](int idx) {
         return typeIsValidForColor(parameters[idx]->type()) &&
                parameters[idx]->modifiers().fFlags == 0 &&
                parameters[idx]->modifiers().fLayout.fBuiltin == SK_INPUT_COLOR_BUILTIN;
     };

     switch (kind) {
         case ProgramKind::kRuntimeColorFilter: {
             // (half4|float4) main(half4|float4)
             if (!typeIsValidForColor(returnType)) {
                 errors.error(offset, "'main' must return: 'vec4', 'float4', or 'half4'");
                 return false;
             }
             bool validParams = (parameters.size() == 1 && paramIsInputColor(0));
             if (!validParams) {
                 errors.error(offset, "'main' parameter must be 'vec4', 'float4', or 'half4'");
                 return false;
             }
             break;
         }
         case ProgramKind::kRuntimeShader: {
             // (half4|float4) main(float2)  -or-  (half4|float4) main(float2, half4|float4)
             if (!typeIsValidForColor(returnType)) {
                 errors.error(offset, "'main' must return: 'vec4', 'float4', or 'half4'");
                 return false;
             }
             bool validParams =
                     (parameters.size() == 1 && paramIsCoords(0)) ||
                     (parameters.size() == 2 && paramIsCoords(0) && paramIsInputColor(1));
             if (!validParams) {
                 errors.error(offset, "'main' parameters must be (float2, (vec4|float4|half4)?)");
                 return false;
             }
             break;
         }
         case ProgramKind::kFragmentProcessor: {
             if (returnType != *context.fTypes.fHalf4) {
                 errors.error(offset, ".fp 'main' must return 'half4'");
                 return false;
             }
             bool validParams = (parameters.size() == 0) ||
                                (parameters.size() == 1 && paramIsCoords(0));
             if (!validParams) {
                 errors.error(offset, ".fp 'main' must be declared main() or main(float2)");
                 return false;
             }
             break;
         }
         case ProgramKind::kGeneric:
             // No rules apply here
             break;
         case ProgramKind::kFragment: {
             bool validParams = (parameters.size() == 0) ||
                                (parameters.size() == 1 && paramIsCoords(0));
             if (!validParams) {
                 errors.error(offset, "shader 'main' must be main() or main(float2)");
                 return false;
             }
             break;
         }
         case ProgramKind::kVertex:
         case ProgramKind::kGeometry:
             if (parameters.size()) {
                 errors.error(offset, "shader 'main' must have zero parameters");
                 return false;
             }
             break;
     }
     return true;
 }

 /**
  * Checks for a previously existing declaration of this function, reporting errors if there is an
  * incompatible symbol. Returns true and sets outExistingDecl to point to the existing declaration
  * (or null if none) on success, returns false on error.
  */
 static bool find_existing_declaration(const Context& context, SymbolTable& symbols, int offset,
                                       StringFragment name,
                                       std::vector<std::unique_ptr<Variable>>& parameters,
                                       const Type* returnType, bool isBuiltin,
                                       const FunctionDeclaration** outExistingDecl) {
     ErrorReporter& errors = context.fErrors;
     const Symbol* entry = symbols[name];
     *outExistingDecl = nullptr;
     if (entry) {
         std::vector<const FunctionDeclaration*> functions;
         switch (entry->kind()) {
             case Symbol::Kind::kUnresolvedFunction:
                 functions = entry->as<UnresolvedFunction>().functions();
                 break;
             case Symbol::Kind::kFunctionDeclaration:
                 functions.push_back(&entry->as<FunctionDeclaration>());
                 break;
             default:
                 errors.error(offset, "symbol '" + name + "' was already defined");
                 return false;
         }
         for (const FunctionDeclaration* other : functions) {
             SkASSERT(name == other->name());
             if (parameters.size() != other->parameters().size()) {
                 continue;
             }
             bool match = true;
             for (size_t i = 0; i < parameters.size(); i++) {
                 if (parameters[i]->type() != other->parameters()[i]->type()) {
                     match = false;
                     break;
                 }
             }
             if (!match) {
                 continue;
             }
             if (*returnType != other->returnType()) {
                 std::vector<const Variable*> paramPtrs;
                 paramPtrs.reserve(parameters.size());
                 for (std::unique_ptr<Variable>& param : parameters) {
                     paramPtrs.push_back(param.get());
                 }
                 FunctionDeclaration invalidDecl(offset,
                                                 &other->modifiers(),
                                                 name,
                                                 std::move(paramPtrs),
                                                 returnType,
                                                 isBuiltin);
                 errors.error(offset,
                              "functions '" + invalidDecl.description() + "' and '" +
                              other->description() + "' differ only in return type");
                 return false;
             }
             for (size_t i = 0; i < parameters.size(); i++) {
                 if (parameters[i]->modifiers() != other->parameters()[i]->modifiers()) {
                     errors.error(offset,
                                  "modifiers on parameter " + to_string((uint64_t)i + 1) +
                                  " differ between declaration and definition");
                     return false;
                 }
             }
             if (other->definition() && !other->isBuiltin()) {
                 errors.error(offset, "duplicate definition of " + other->description());
                 return false;
             }
             *outExistingDecl = other;
             break;
         }
     }
     return true;
 }

 const FunctionDeclaration* FunctionDeclaration::Convert(const Context& context,
         SymbolTable& symbols, ModifiersPool& modifiersPool, int offset, const Modifiers* modifiers,
         StringFragment name, std::vector<std::unique_ptr<Variable>> parameters,
         const Type* returnType, bool isBuiltin) {
     bool isMain = (name == "main");

     const FunctionDeclaration* decl = nullptr;
     if (!check_modifiers(context, offset, *modifiers) ||
         !check_return_type(context, offset, *returnType, isBuiltin) ||
         !check_parameters(context, modifiersPool, parameters, isMain, isBuiltin) ||
         (isMain && !check_main_signature(context, offset, *returnType, parameters, isBuiltin)) ||
         !find_existing_declaration(context, symbols, offset, name, parameters, returnType,
                                    isBuiltin, &decl)) {
         return nullptr;
     }
     std::vector<const Variable*> finalParameters;
     finalParameters.reserve(parameters.size());
     for (auto& param : parameters) {
         finalParameters.push_back(symbols.takeOwnershipOfSymbol(std::move(param)));
     }
     if (decl) {
         return decl;
     }
     auto result = std::make_unique<FunctionDeclaration>(offset, modifiers, name,
                                                         std::move(finalParameters), returnType,
                                                         isBuiltin);
     return symbols.add(std::move(result));
 }

 }  // namespace SkSL
	/*
	* Copyright 2021 Google LLC.
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#include "src/sksl/ir/SkSLFunctionDeclaration.h"

	#include "src/sksl/SkSLCompiler.h"
	#include "src/sksl/SkSLIRGenerator.h"
	#include "src/sksl/ir/SkSLUnresolvedFunction.h"

	namespace SkSL {

	static bool check_modifiers(const Context& context, int offset, const Modifiers& modifiers) {
	IRGenerator::CheckModifiers(
	context,
	offset,
	modifiers,
	Modifiers::kHasSideEffects_Flag \| Modifiers::kInline_Flag \| Modifiers::kNoInline_Flag,
	/permittedLayoutFlags=/0);
	if ((modifiers.fFlags & Modifiers::kInline_Flag) &&
	(modifiers.fFlags & Modifiers::kNoInline_Flag)) {
	context.fErrors.error(offset, "functions cannot be both 'inline' and 'noinline'");
	return false;
	}
	return true;
	}

	static bool check_return_type(const Context& context, int offset, const Type& returnType,
	bool isBuiltin) {
	ErrorReporter& errors = context.fErrors;
	if (returnType.isArray()) {
	errors.error(offset, "functions may not return type '" + returnType.displayName() + "'");
	return false;
	}
	if (context.fConfig->strictES2Mode() && returnType.isOrContainsArray()) {
	errors.error(offset, "functions may not return structs containing arrays");
	return false;
	}
	if (!isBuiltin && !returnType.isVoid() && returnType.componentType().isOpaque()) {
	errors.error(offset, "functions may not return opaque type '" + returnType.displayName() +
	"'");
	return false;
	}
	return true;
	}

	static bool check_parameters(const Context& context, ModifiersPool& modifiersPool,
	std::vector<std::unique_ptr<Variable>>& parameters, bool isMain,
	bool isBuiltin) {
	auto typeIsValidForColor = [&](const Type& type) {
	return type == context.fTypes.fHalf4 \|\| type == context.fTypes.fFloat4;
	};

	// Check modifiers on each function parameter.
	for (auto& param : parameters) {
	IRGenerator::CheckModifiers(context, param->fOffset, param->modifiers(),
	Modifiers::kConst_Flag \| Modifiers::kIn_Flag \|
	Modifiers::kOut_Flag, /permittedLayoutFlags=/0);
	const Type& type = param->type();
	// Only the (builtin) declarations of 'sample' are allowed to have shader/colorFilter or FP
	// parameters. You can pass other opaque types to functions safely; this restriction is
	// specific to "child" objects.
	if ((type.isEffectChild() \|\| type.isFragmentProcessor()) && !isBuiltin) {
	context.fErrors.error(param->fOffset, "parameters of type '" + type.displayName() +
	"' not allowed");
	return false;
	}

	Modifiers m = param->modifiers();
	ProgramKind kind = context.fConfig->fKind;
	if (isMain && (kind == ProgramKind::kRuntimeColorFilter \|\|
	kind == ProgramKind::kRuntimeShader \|\|
	kind == ProgramKind::kFragmentProcessor)) {
	// We verify that the signature is fully correct later. For now, if this is an .fp or
	// runtime effect of any flavor, a float2 param is supposed to be the coords, and
	// a half4/float parameter is supposed to be the input color:
	if (type == *context.fTypes.fFloat2) {
	m.fLayout.fBuiltin = SK_MAIN_COORDS_BUILTIN;
	} else if(typeIsValidForColor(type)) {
	m.fLayout.fBuiltin = SK_INPUT_COLOR_BUILTIN;
	}
	if (m.fLayout.fBuiltin) {
	param->setModifiers(modifiersPool.add(m));
	}
	}
	if (isMain && (kind == ProgramKind::kFragment)) {
	// For testing purposes, we have .sksl inputs that are treated as both runtime effects
	// and fragment shaders. To make that work, fragment shaders are allowed to have a
	// coords parameter. We turn it into sk_FragCoord.
	if (type == *context.fTypes.fFloat2) {
	m.fLayout.fBuiltin = SK_FRAGCOORD_BUILTIN;
	param->setModifiers(modifiersPool.add(m));
	}
	}
	}
	return true;
	}

	static bool check_main_signature(const Context& context, int offset, const Type& returnType,
	std::vector<std::unique_ptr<Variable>>& parameters,
	bool isBuiltin) {
	ErrorReporter& errors = context.fErrors;
	ProgramKind kind = context.fConfig->fKind;

	auto typeIsValidForColor = [&](const Type& type) {
	return type == context.fTypes.fHalf4 \|\| type == context.fTypes.fFloat4;
	};

	auto paramIsCoords = [&](int idx) {
	const Variable& p = *parameters[idx];
	return p.type() == *context.fTypes.fFloat2 &&
	p.modifiers().fFlags == 0 &&
	p.modifiers().fLayout.fBuiltin == (kind == ProgramKind::kFragment
	? SK_FRAGCOORD_BUILTIN
	: SK_MAIN_COORDS_BUILTIN);
	};

	auto paramIsInputColor = [&](int idx) {
	return typeIsValidForColor(parameters[idx]->type()) &&
	parameters[idx]->modifiers().fFlags == 0 &&
	parameters[idx]->modifiers().fLayout.fBuiltin == SK_INPUT_COLOR_BUILTIN;
	};

	switch (kind) {
	case ProgramKind::kRuntimeColorFilter: {
	// (half4\|float4) main(half4\|float4)
	if (!typeIsValidForColor(returnType)) {
	errors.error(offset, "'main' must return: 'vec4', 'float4', or 'half4'");
	return false;
	}
	bool validParams = (parameters.size() == 1 && paramIsInputColor(0));
	if (!validParams) {
	errors.error(offset, "'main' parameter must be 'vec4', 'float4', or 'half4'");
	return false;
	}
	break;
	}
	case ProgramKind::kRuntimeShader: {
	// (half4\|float4) main(float2) -or- (half4\|float4) main(float2, half4\|float4)
	if (!typeIsValidForColor(returnType)) {
	errors.error(offset, "'main' must return: 'vec4', 'float4', or 'half4'");
	return false;
	}
	bool validParams =
	(parameters.size() == 1 && paramIsCoords(0)) \|\|
	(parameters.size() == 2 && paramIsCoords(0) && paramIsInputColor(1));
	if (!validParams) {
	errors.error(offset, "'main' parameters must be (float2, (vec4\|float4\|half4)?)");
	return false;
	}
	break;
	}
	case ProgramKind::kFragmentProcessor: {
	if (returnType != *context.fTypes.fHalf4) {
	errors.error(offset, ".fp 'main' must return 'half4'");
	return false;
	}
	bool validParams = (parameters.size() == 0) \|\|
	(parameters.size() == 1 && paramIsCoords(0));
	if (!validParams) {
	errors.error(offset, ".fp 'main' must be declared main() or main(float2)");
	return false;
	}
	break;
	}
	case ProgramKind::kGeneric:
	// No rules apply here
	break;
	case ProgramKind::kFragment: {
	bool validParams = (parameters.size() == 0) \|\|
	(parameters.size() == 1 && paramIsCoords(0));
	if (!validParams) {
	errors.error(offset, "shader 'main' must be main() or main(float2)");
	return false;
	}
	break;
	}
	case ProgramKind::kVertex:
	case ProgramKind::kGeometry:
	if (parameters.size()) {
	errors.error(offset, "shader 'main' must have zero parameters");
	return false;
	}
	break;
	}
	return true;
	}

	/**
	* Checks for a previously existing declaration of this function, reporting errors if there is an
	* incompatible symbol. Returns true and sets outExistingDecl to point to the existing declaration
	* (or null if none) on success, returns false on error.
	*/
	static bool find_existing_declaration(const Context& context, SymbolTable& symbols, int offset,
	StringFragment name,
	std::vector<std::unique_ptr<Variable>>& parameters,
	const Type* returnType, bool isBuiltin,
	const FunctionDeclaration** outExistingDecl) {
	ErrorReporter& errors = context.fErrors;
	const Symbol* entry = symbols[name];
	*outExistingDecl = nullptr;
	if (entry) {
	std::vector<const FunctionDeclaration*> functions;
	switch (entry->kind()) {
	case Symbol::Kind::kUnresolvedFunction:
	functions = entry->as<UnresolvedFunction>().functions();
	break;
	case Symbol::Kind::kFunctionDeclaration:
	functions.push_back(&entry->as<FunctionDeclaration>());
	break;
	default:
	errors.error(offset, "symbol '" + name + "' was already defined");
	return false;
	}
	for (const FunctionDeclaration* other : functions) {
	SkASSERT(name == other->name());
	if (parameters.size() != other->parameters().size()) {
	continue;
	}
	bool match = true;
	for (size_t i = 0; i < parameters.size(); i++) {
	if (parameters[i]->type() != other->parameters()[i]->type()) {
	match = false;
	break;
	}
	}
	if (!match) {
	continue;
	}
	if (*returnType != other->returnType()) {
	std::vector<const Variable*> paramPtrs;
	paramPtrs.reserve(parameters.size());
	for (std::unique_ptr<Variable>& param : parameters) {
	paramPtrs.push_back(param.get());
	}
	FunctionDeclaration invalidDecl(offset,
	&other->modifiers(),
	name,
	std::move(paramPtrs),
	returnType,
	isBuiltin);
	errors.error(offset,
	"functions '" + invalidDecl.description() + "' and '" +
	other->description() + "' differ only in return type");
	return false;
	}
	for (size_t i = 0; i < parameters.size(); i++) {
	if (parameters[i]->modifiers() != other->parameters()[i]->modifiers()) {
	errors.error(offset,
	"modifiers on parameter " + to_string((uint64_t)i + 1) +
	" differ between declaration and definition");
	return false;
	}
	}
	if (other->definition() && !other->isBuiltin()) {
	errors.error(offset, "duplicate definition of " + other->description());
	return false;
	}
	*outExistingDecl = other;
	break;
	}
	}
	return true;
	}

	const FunctionDeclaration* FunctionDeclaration::Convert(const Context& context,
	SymbolTable& symbols, ModifiersPool& modifiersPool, int offset, const Modifiers* modifiers,
	StringFragment name, std::vector<std::unique_ptr<Variable>> parameters,
	const Type* returnType, bool isBuiltin) {
	bool isMain = (name == "main");

	const FunctionDeclaration* decl = nullptr;
	if (!check_modifiers(context, offset, *modifiers) \|\|
	!check_return_type(context, offset, *returnType, isBuiltin) \|\|
	!check_parameters(context, modifiersPool, parameters, isMain, isBuiltin) \|\|
	(isMain && !check_main_signature(context, offset, *returnType, parameters, isBuiltin)) \|\|
	!find_existing_declaration(context, symbols, offset, name, parameters, returnType,
	isBuiltin, &decl)) {
	return nullptr;
	}
	std::vector<const Variable*> finalParameters;
	finalParameters.reserve(parameters.size());
	for (auto& param : parameters) {
	finalParameters.push_back(symbols.takeOwnershipOfSymbol(std::move(param)));
	}
	if (decl) {
	return decl;
	}
	auto result = std::make_unique<FunctionDeclaration>(offset, modifiers, name,
	std::move(finalParameters), returnType,
	isBuiltin);
	return symbols.add(std::move(result));
	}

	} // namespace SkSL