blob: 316c0fd287db4a2131d916340400834b9892aa4f [file] [log] [blame]
/*
* Copyright 2016 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "src/sksl/SkSLParser.h"
#include <memory>
#include "stdio.h"
#include "include/private/SkSLModifiers.h"
#include "src/sksl/SkSLASTNode.h"
#include "src/sksl/ir/SkSLSymbolTable.h"
#include "src/sksl/ir/SkSLType.h"
#ifndef SKSL_STANDALONE
#include "include/private/SkOnce.h"
#endif
namespace SkSL {
static constexpr int kMaxParseDepth = 50;
static constexpr int kMaxStructDepth = 8;
static bool struct_is_too_deeply_nested(const Type& type, int limit) {
if (limit < 0) {
return true;
}
if (type.isStruct()) {
for (const Type::Field& f : type.fields()) {
if (struct_is_too_deeply_nested(*f.fType, limit - 1)) {
return true;
}
}
}
return false;
}
static int parse_modifier_token(Token::Kind token) {
switch (token) {
case Token::Kind::TK_UNIFORM: return Modifiers::kUniform_Flag;
case Token::Kind::TK_CONST: return Modifiers::kConst_Flag;
case Token::Kind::TK_IN: return Modifiers::kIn_Flag;
case Token::Kind::TK_OUT: return Modifiers::kOut_Flag;
case Token::Kind::TK_INOUT: return Modifiers::kIn_Flag | Modifiers::kOut_Flag;
case Token::Kind::TK_FLAT: return Modifiers::kFlat_Flag;
case Token::Kind::TK_NOPERSPECTIVE: return Modifiers::kNoPerspective_Flag;
case Token::Kind::TK_HASSIDEEFFECTS: return Modifiers::kHasSideEffects_Flag;
case Token::Kind::TK_INLINE: return Modifiers::kInline_Flag;
case Token::Kind::TK_NOINLINE: return Modifiers::kNoInline_Flag;
case Token::Kind::TK_HIGHP: return Modifiers::kHighp_Flag;
case Token::Kind::TK_MEDIUMP: return Modifiers::kMediump_Flag;
case Token::Kind::TK_LOWP: return Modifiers::kLowp_Flag;
case Token::Kind::TK_ES3: return Modifiers::kES3_Flag;
default: return 0;
}
}
class AutoDepth {
public:
AutoDepth(Parser* p)
: fParser(p)
, fDepth(0) {}
~AutoDepth() {
fParser->fDepth -= fDepth;
}
bool increase() {
++fDepth;
++fParser->fDepth;
if (fParser->fDepth > kMaxParseDepth) {
fParser->error(fParser->peek(), String("exceeded max parse depth"));
return false;
}
return true;
}
private:
Parser* fParser;
int fDepth;
};
std::unordered_map<String, Parser::LayoutToken>* Parser::layoutTokens;
void Parser::InitLayoutMap() {
layoutTokens = new std::unordered_map<String, LayoutToken>;
#define TOKEN(name, text) (*layoutTokens)[text] = LayoutToken::name
TOKEN(LOCATION, "location");
TOKEN(OFFSET, "offset");
TOKEN(BINDING, "binding");
TOKEN(INDEX, "index");
TOKEN(SET, "set");
TOKEN(BUILTIN, "builtin");
TOKEN(INPUT_ATTACHMENT_INDEX, "input_attachment_index");
TOKEN(ORIGIN_UPPER_LEFT, "origin_upper_left");
TOKEN(BLEND_SUPPORT_ALL_EQUATIONS, "blend_support_all_equations");
TOKEN(PUSH_CONSTANT, "push_constant");
TOKEN(POINTS, "points");
TOKEN(LINES, "lines");
TOKEN(LINE_STRIP, "line_strip");
TOKEN(LINES_ADJACENCY, "lines_adjacency");
TOKEN(TRIANGLES, "triangles");
TOKEN(TRIANGLE_STRIP, "triangle_strip");
TOKEN(TRIANGLES_ADJACENCY, "triangles_adjacency");
TOKEN(MAX_VERTICES, "max_vertices");
TOKEN(INVOCATIONS, "invocations");
TOKEN(SRGB_UNPREMUL, "srgb_unpremul");
#undef TOKEN
}
Parser::Parser(skstd::string_view text, SymbolTable& symbols, ErrorReporter& errors)
: fText(text)
, fPushback(Token::Kind::TK_NONE, -1, -1)
, fSymbols(symbols)
, fErrors(&errors) {
fLexer.start(text);
static const bool layoutMapInitialized = []{ return (void)InitLayoutMap(), true; }();
(void) layoutMapInitialized;
}
template <typename... Args>
ASTNode::ID Parser::createNode(Args&&... args) {
ASTNode::ID result(fFile->fNodes.size());
fFile->fNodes.emplace_back(&fFile->fNodes, std::forward<Args>(args)...);
return result;
}
ASTNode::ID Parser::addChild(ASTNode::ID target, ASTNode::ID child) {
fFile->fNodes[target.fValue].addChild(child);
return child;
}
void Parser::createEmptyChild(ASTNode::ID target) {
ASTNode::ID child(fFile->fNodes.size());
fFile->fNodes.emplace_back();
fFile->fNodes[target.fValue].addChild(child);
}
/* (directive | section | declaration)* END_OF_FILE */
std::unique_ptr<ASTFile> Parser::compilationUnit() {
fFile = std::make_unique<ASTFile>();
fFile->fNodes.reserve(fText.size() / 10); // a typical program is approx 10:1 for chars:nodes
ASTNode::ID result = this->createNode(/*offset=*/0, ASTNode::Kind::kFile);
fFile->fRoot = result;
for (;;) {
switch (this->peek().fKind) {
case Token::Kind::TK_END_OF_FILE:
return std::move(fFile);
case Token::Kind::TK_DIRECTIVE: {
ASTNode::ID dir = this->directive();
if (fErrors->errorCount()) {
return nullptr;
}
if (dir) {
getNode(result).addChild(dir);
}
break;
}
case Token::Kind::TK_INVALID: {
this->error(this->peek(), String("invalid token"));
return nullptr;
}
default: {
ASTNode::ID decl = this->declaration();
if (fErrors->errorCount()) {
return nullptr;
}
if (decl) {
getNode(result).addChild(decl);
}
}
}
}
return std::move(fFile);
}
Token Parser::nextRawToken() {
if (fPushback.fKind != Token::Kind::TK_NONE) {
Token result = fPushback;
fPushback.fKind = Token::Kind::TK_NONE;
return result;
}
Token result = fLexer.next();
return result;
}
Token Parser::nextToken() {
Token token = this->nextRawToken();
while (token.fKind == Token::Kind::TK_WHITESPACE ||
token.fKind == Token::Kind::TK_LINE_COMMENT ||
token.fKind == Token::Kind::TK_BLOCK_COMMENT) {
token = this->nextRawToken();
}
return token;
}
void Parser::pushback(Token t) {
SkASSERT(fPushback.fKind == Token::Kind::TK_NONE);
fPushback = std::move(t);
}
Token Parser::peek() {
if (fPushback.fKind == Token::Kind::TK_NONE) {
fPushback = this->nextToken();
}
return fPushback;
}
bool Parser::checkNext(Token::Kind kind, Token* result) {
if (fPushback.fKind != Token::Kind::TK_NONE && fPushback.fKind != kind) {
return false;
}
Token next = this->nextToken();
if (next.fKind == kind) {
if (result) {
*result = next;
}
return true;
}
this->pushback(std::move(next));
return false;
}
bool Parser::expect(Token::Kind kind, const char* expected, Token* result) {
Token next = this->nextToken();
if (next.fKind == kind) {
if (result) {
*result = std::move(next);
}
return true;
} else {
this->error(next, "expected " + String(expected) + ", but found '" +
this->text(next) + "'");
return false;
}
}
bool Parser::expectIdentifier(Token* result) {
if (!this->expect(Token::Kind::TK_IDENTIFIER, "an identifier", result)) {
return false;
}
if (this->isType(this->text(*result))) {
this->error(*result, "expected an identifier, but found type '" +
this->text(*result) + "'");
return false;
}
return true;
}
skstd::string_view Parser::text(Token token) {
return skstd::string_view(fText.begin() + token.fOffset, token.fLength);
}
void Parser::error(Token token, String msg) {
this->error(token.fOffset, msg);
}
void Parser::error(int offset, String msg) {
fErrors->error(offset, msg);
}
bool Parser::isType(skstd::string_view name) {
const Symbol* s = fSymbols[name];
return s && s->is<Type>();
}
bool Parser::isArrayType(ASTNode::ID type) {
const ASTNode& node = this->getNode(type);
SkASSERT(node.fKind == ASTNode::Kind::kType);
return node.begin() != node.end();
}
/* DIRECTIVE(#version) INT_LITERAL ("es" | "compatibility")? |
DIRECTIVE(#extension) IDENTIFIER COLON IDENTIFIER */
ASTNode::ID Parser::directive() {
Token start;
if (!this->expect(Token::Kind::TK_DIRECTIVE, "a directive", &start)) {
return ASTNode::ID::Invalid();
}
skstd::string_view text = this->text(start);
if (text == "#extension") {
Token name;
if (!this->expectIdentifier(&name)) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_COLON, "':'")) {
return ASTNode::ID::Invalid();
}
// FIXME: need to start paying attention to this token
if (!this->expect(Token::Kind::TK_IDENTIFIER, "an identifier")) {
return ASTNode::ID::Invalid();
}
return this->createNode(start.fOffset, ASTNode::Kind::kExtension, this->text(name));
} else {
this->error(start, "unsupported directive '" + this->text(start) + "'");
return ASTNode::ID::Invalid();
}
}
/* modifiers (interfaceBlock | structVarDeclaration | SEMICOLON |
type IDENTIFIER (varDeclarationEnd | LPAREN functionDeclarationEnd))) */
ASTNode::ID Parser::declaration() {
Token lookahead = this->peek();
switch (lookahead.fKind) {
case Token::Kind::TK_SEMICOLON:
this->error(lookahead.fOffset, "expected a declaration, but found ';'");
return ASTNode::ID::Invalid();
default:
break;
}
Modifiers modifiers = this->modifiers();
lookahead = this->peek();
if (lookahead.fKind == Token::Kind::TK_IDENTIFIER && !this->isType(this->text(lookahead))) {
// we have an identifier that's not a type, could be the start of an interface block
return this->interfaceBlock(modifiers);
}
if (lookahead.fKind == Token::Kind::TK_STRUCT) {
return this->structVarDeclaration(modifiers);
}
if (lookahead.fKind == Token::Kind::TK_SEMICOLON) {
this->nextToken();
return this->createNode(lookahead.fOffset, ASTNode::Kind::kModifiers, modifiers);
}
ASTNode::ID type = this->type();
if (!type) {
return ASTNode::ID::Invalid();
}
Token name;
if (!this->expectIdentifier(&name)) {
return ASTNode::ID::Invalid();
}
if (this->checkNext(Token::Kind::TK_LPAREN)) {
return this->functionDeclarationEnd(modifiers, type, name);
} else {
return this->varDeclarationEnd(modifiers, type, this->text(name));
}
}
/* (RPAREN | VOID RPAREN | parameter (COMMA parameter)* RPAREN) (block | SEMICOLON) */
ASTNode::ID Parser::functionDeclarationEnd(Modifiers modifiers,
ASTNode::ID type,
const Token& name) {
ASTNode::ID result = this->createNode(name.fOffset, ASTNode::Kind::kFunction);
ASTNode::FunctionData fd(modifiers, this->text(name), 0);
getNode(result).addChild(type);
Token lookahead = this->peek();
if (lookahead.fKind == Token::Kind::TK_RPAREN) {
// `()` means no parameters at all.
} else if (lookahead.fKind == Token::Kind::TK_IDENTIFIER && this->text(lookahead) == "void") {
// `(void)` also means no parameters at all.
this->nextToken();
} else {
for (;;) {
ASTNode::ID parameter = this->parameter();
if (!parameter) {
return ASTNode::ID::Invalid();
}
++fd.fParameterCount;
getNode(result).addChild(parameter);
if (!this->checkNext(Token::Kind::TK_COMMA)) {
break;
}
}
}
getNode(result).setFunctionData(fd);
if (!this->expect(Token::Kind::TK_RPAREN, "')'")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID body;
if (!this->checkNext(Token::Kind::TK_SEMICOLON)) {
body = this->block();
if (!body) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(body);
}
return result;
}
/* (varDeclarations | expressionStatement) */
ASTNode::ID Parser::varDeclarationsOrExpressionStatement() {
Token nextToken = this->peek();
if (nextToken.fKind == Token::Kind::TK_CONST) {
// Statements that begin with `const` might be variable declarations, but can't be legal
// SkSL expression-statements. (SkSL constructors don't take a `const` modifier.)
return this->varDeclarations();
}
if (nextToken.fKind == Token::Kind::TK_HIGHP ||
nextToken.fKind == Token::Kind::TK_MEDIUMP ||
nextToken.fKind == Token::Kind::TK_LOWP ||
this->isType(this->text(nextToken))) {
// Statements that begin with a typename are most often variable declarations, but
// occasionally the type is part of a constructor, and these are actually expression-
// statements in disguise. First, attempt the common case: parse it as a vardecl.
Checkpoint checkpoint(this);
VarDeclarationsPrefix prefix;
if (this->varDeclarationsPrefix(&prefix)) {
checkpoint.accept();
return this->varDeclarationEnd(prefix.modifiers, prefix.type, this->text(prefix.name));
}
// If this statement wasn't actually a vardecl after all, rewind and try parsing it as an
// expression-statement instead.
checkpoint.rewind();
}
return this->expressionStatement();
}
// Helper function for varDeclarations(). If this function succeeds, we assume that the rest of the
// statement is a variable-declaration statement, not an expression-statement.
bool Parser::varDeclarationsPrefix(VarDeclarationsPrefix* prefixData) {
prefixData->modifiers = this->modifiers();
prefixData->type = this->type();
if (!prefixData->type) {
return false;
}
return this->expectIdentifier(&prefixData->name);
}
/* modifiers type IDENTIFIER varDeclarationEnd */
ASTNode::ID Parser::varDeclarations() {
VarDeclarationsPrefix prefix;
if (!this->varDeclarationsPrefix(&prefix)) {
return ASTNode::ID::Invalid();
}
return this->varDeclarationEnd(prefix.modifiers, prefix.type, this->text(prefix.name));
}
/* STRUCT IDENTIFIER LBRACE varDeclaration* RBRACE */
ASTNode::ID Parser::structDeclaration() {
if (!this->expect(Token::Kind::TK_STRUCT, "'struct'")) {
return ASTNode::ID::Invalid();
}
Token name;
if (!this->expectIdentifier(&name)) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_LBRACE, "'{'")) {
return ASTNode::ID::Invalid();
}
std::vector<Type::Field> fields;
while (this->peek().fKind != Token::Kind::TK_RBRACE) {
ASTNode::ID decls = this->varDeclarations();
if (!decls) {
return ASTNode::ID::Invalid();
}
ASTNode& declsNode = getNode(decls);
const Modifiers& modifiers = declsNode.begin()->getModifiers();
if (modifiers.fFlags != Modifiers::kNo_Flag) {
String desc = modifiers.description();
desc.pop_back(); // remove trailing space
this->error(declsNode.fOffset,
"modifier '" + desc + "' is not permitted on a struct field");
}
const Symbol* symbol = fSymbols[(declsNode.begin() + 1)->getStringView()];
SkASSERT(symbol);
const Type* type = &symbol->as<Type>();
if (type->isOpaque()) {
this->error(declsNode.fOffset,
"opaque type '" + type->name() + "' is not permitted in a struct");
}
for (auto iter = declsNode.begin() + 2; iter != declsNode.end(); ++iter) {
ASTNode& var = *iter;
const ASTNode::VarData& vd = var.getVarData();
// Read array size if one is present.
if (vd.fIsArray) {
const ASTNode& size = *var.begin();
if (!size || size.fKind != ASTNode::Kind::kInt) {
this->error(declsNode.fOffset, "array size in struct field must be a constant");
return ASTNode::ID::Invalid();
}
if (size.getInt() <= 0 || size.getInt() > INT_MAX) {
this->error(declsNode.fOffset, "array size is invalid");
return ASTNode::ID::Invalid();
}
// Add the array dimensions to our type.
int arraySize = size.getInt();
type = fSymbols.addArrayDimension(type, arraySize);
}
fields.push_back(Type::Field(modifiers, vd.fName, type));
if (vd.fIsArray ? var.begin()->fNext : var.fFirstChild) {
this->error(declsNode.fOffset, "initializers are not permitted on struct fields");
}
}
}
if (!this->expect(Token::Kind::TK_RBRACE, "'}'")) {
return ASTNode::ID::Invalid();
}
if (fields.empty()) {
this->error(name.fOffset,
"struct '" + this->text(name) + "' must contain at least one field");
return ASTNode::ID::Invalid();
}
std::unique_ptr<Type> newType = Type::MakeStructType(name.fOffset, this->text(name), fields);
if (struct_is_too_deeply_nested(*newType, kMaxStructDepth)) {
this->error(name.fOffset, "struct '" + this->text(name) + "' is too deeply nested");
return ASTNode::ID::Invalid();
}
fSymbols.add(std::move(newType));
return this->createNode(name.fOffset, ASTNode::Kind::kType, this->text(name));
}
/* structDeclaration ((IDENTIFIER varDeclarationEnd) | SEMICOLON) */
ASTNode::ID Parser::structVarDeclaration(Modifiers modifiers) {
ASTNode::ID type = this->structDeclaration();
if (!type) {
return ASTNode::ID::Invalid();
}
Token name;
if (this->checkNext(Token::Kind::TK_IDENTIFIER, &name)) {
return this->varDeclarationEnd(modifiers, std::move(type), this->text(name));
}
this->expect(Token::Kind::TK_SEMICOLON, "';'");
return type;
}
/* (LBRACKET expression? RBRACKET)* (EQ assignmentExpression)? (COMMA IDENTIFER
(LBRACKET expression? RBRACKET)* (EQ assignmentExpression)?)* SEMICOLON */
ASTNode::ID Parser::varDeclarationEnd(Modifiers mods, ASTNode::ID type, skstd::string_view name) {
int offset = this->peek().fOffset;
ASTNode::ID result = this->createNode(offset, ASTNode::Kind::kVarDeclarations);
this->addChild(result, this->createNode(offset, ASTNode::Kind::kModifiers, mods));
getNode(result).addChild(type);
auto parseArrayDimensions = [&](ASTNode::ID currentVar, ASTNode::VarData* vd) -> bool {
while (this->checkNext(Token::Kind::TK_LBRACKET)) {
if (vd->fIsArray || this->isArrayType(type)) {
this->error(this->peek(), "multi-dimensional arrays are not supported");
return false;
}
if (this->checkNext(Token::Kind::TK_RBRACKET)) {
this->createEmptyChild(currentVar);
} else {
ASTNode::ID size = this->expression();
if (!size) {
return false;
}
getNode(currentVar).addChild(size);
if (!this->expect(Token::Kind::TK_RBRACKET, "']'")) {
return false;
}
}
vd->fIsArray = true;
}
return true;
};
auto parseInitializer = [this](ASTNode::ID currentVar) -> bool {
if (this->checkNext(Token::Kind::TK_EQ)) {
ASTNode::ID value = this->assignmentExpression();
if (!value) {
return false;
}
getNode(currentVar).addChild(value);
}
return true;
};
ASTNode::ID currentVar = this->createNode(offset, ASTNode::Kind::kVarDeclaration);
ASTNode::VarData vd{name, /*isArray=*/false};
getNode(result).addChild(currentVar);
if (!parseArrayDimensions(currentVar, &vd)) {
return ASTNode::ID::Invalid();
}
getNode(currentVar).setVarData(vd);
if (!parseInitializer(currentVar)) {
return ASTNode::ID::Invalid();
}
while (this->checkNext(Token::Kind::TK_COMMA)) {
Token identifierName;
if (!this->expectIdentifier(&identifierName)) {
return ASTNode::ID::Invalid();
}
currentVar = ASTNode::ID(fFile->fNodes.size());
vd = ASTNode::VarData{this->text(identifierName), /*isArray=*/false};
fFile->fNodes.emplace_back(&fFile->fNodes, offset, ASTNode::Kind::kVarDeclaration);
getNode(result).addChild(currentVar);
if (!parseArrayDimensions(currentVar, &vd)) {
return ASTNode::ID::Invalid();
}
getNode(currentVar).setVarData(vd);
if (!parseInitializer(currentVar)) {
return ASTNode::ID::Invalid();
}
}
if (!this->expect(Token::Kind::TK_SEMICOLON, "';'")) {
return ASTNode::ID::Invalid();
}
return result;
}
/* modifiers type IDENTIFIER (LBRACKET INT_LITERAL RBRACKET)? */
ASTNode::ID Parser::parameter() {
Modifiers modifiers = this->modifiersWithDefaults(0);
ASTNode::ID type = this->type();
if (!type) {
return ASTNode::ID::Invalid();
}
Token name;
if (!this->expectIdentifier(&name)) {
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(name.fOffset, ASTNode::Kind::kParameter);
ASTNode::ParameterData pd(modifiers, this->text(name), 0);
getNode(result).addChild(type);
while (this->checkNext(Token::Kind::TK_LBRACKET)) {
if (pd.fIsArray || this->isArrayType(type)) {
this->error(this->peek(), "multi-dimensional arrays are not supported");
return ASTNode::ID::Invalid();
}
Token sizeToken;
if (!this->expect(Token::Kind::TK_INT_LITERAL, "a positive integer", &sizeToken)) {
return ASTNode::ID::Invalid();
}
skstd::string_view arraySizeFrag = this->text(sizeToken);
SKSL_INT arraySize;
if (!SkSL::stoi(arraySizeFrag, &arraySize)) {
this->error(sizeToken, "array size is too large: " + arraySizeFrag);
return ASTNode::ID::Invalid();
}
this->addChild(result, this->createNode(sizeToken.fOffset, ASTNode::Kind::kInt, arraySize));
if (!this->expect(Token::Kind::TK_RBRACKET, "']'")) {
return ASTNode::ID::Invalid();
}
pd.fIsArray = true;
}
getNode(result).setParameterData(pd);
return result;
}
/** EQ INT_LITERAL */
int Parser::layoutInt() {
if (!this->expect(Token::Kind::TK_EQ, "'='")) {
return -1;
}
Token resultToken;
if (!this->expect(Token::Kind::TK_INT_LITERAL, "a non-negative integer", &resultToken)) {
return -1;
}
skstd::string_view resultFrag = this->text(resultToken);
SKSL_INT resultValue;
if (!SkSL::stoi(resultFrag, &resultValue)) {
this->error(resultToken, "value in layout is too large: " + resultFrag);
return -1;
}
return resultValue;
}
/** EQ IDENTIFIER */
skstd::string_view Parser::layoutIdentifier() {
if (!this->expect(Token::Kind::TK_EQ, "'='")) {
return skstd::string_view();
}
Token resultToken;
if (!this->expectIdentifier(&resultToken)) {
return skstd::string_view();
}
return this->text(resultToken);
}
/* LAYOUT LPAREN IDENTIFIER (EQ INT_LITERAL)? (COMMA IDENTIFIER (EQ INT_LITERAL)?)* RPAREN */
Layout Parser::layout() {
int flags = 0;
int location = -1;
int offset = -1;
int binding = -1;
int index = -1;
int set = -1;
int builtin = -1;
int inputAttachmentIndex = -1;
Layout::Primitive primitive = Layout::kUnspecified_Primitive;
int maxVertices = -1;
int invocations = -1;
if (this->checkNext(Token::Kind::TK_LAYOUT)) {
if (!this->expect(Token::Kind::TK_LPAREN, "'('")) {
return Layout(flags, location, offset, binding, index, set, builtin,
inputAttachmentIndex, primitive, maxVertices, invocations);
}
for (;;) {
Token t = this->nextToken();
String text(this->text(t));
auto setFlag = [&](Layout::Flag f) {
if (flags & f) {
this->error(t, "layout qualifier '" + text + "' appears more than once");
}
flags |= f;
};
auto setPrimitive = [&](Layout::Primitive p) {
if (flags & Layout::kPrimitive_Flag) {
this->error(t, "only one primitive-type layout qualifier is allowed");
}
flags |= Layout::kPrimitive_Flag;
primitive = p;
};
auto found = layoutTokens->find(text);
if (found != layoutTokens->end()) {
switch (found->second) {
case LayoutToken::ORIGIN_UPPER_LEFT:
setFlag(Layout::kOriginUpperLeft_Flag);
break;
case LayoutToken::PUSH_CONSTANT:
setFlag(Layout::kPushConstant_Flag);
break;
case LayoutToken::BLEND_SUPPORT_ALL_EQUATIONS:
setFlag(Layout::kBlendSupportAllEquations_Flag);
break;
case LayoutToken::SRGB_UNPREMUL:
setFlag(Layout::kSRGBUnpremul_Flag);
break;
case LayoutToken::LOCATION:
setFlag(Layout::kLocation_Flag);
location = this->layoutInt();
break;
case LayoutToken::OFFSET:
setFlag(Layout::kOffset_Flag);
offset = this->layoutInt();
break;
case LayoutToken::BINDING:
setFlag(Layout::kBinding_Flag);
binding = this->layoutInt();
break;
case LayoutToken::INDEX:
setFlag(Layout::kIndex_Flag);
index = this->layoutInt();
break;
case LayoutToken::SET:
setFlag(Layout::kSet_Flag);
set = this->layoutInt();
break;
case LayoutToken::BUILTIN:
setFlag(Layout::kBuiltin_Flag);
builtin = this->layoutInt();
break;
case LayoutToken::INPUT_ATTACHMENT_INDEX:
setFlag(Layout::kInputAttachmentIndex_Flag);
inputAttachmentIndex = this->layoutInt();
break;
case LayoutToken::POINTS:
setPrimitive(Layout::kPoints_Primitive);
break;
case LayoutToken::LINES:
setPrimitive(Layout::kLines_Primitive);
break;
case LayoutToken::LINE_STRIP:
setPrimitive(Layout::kLineStrip_Primitive);
break;
case LayoutToken::LINES_ADJACENCY:
setPrimitive(Layout::kLinesAdjacency_Primitive);
break;
case LayoutToken::TRIANGLES:
setPrimitive(Layout::kTriangles_Primitive);
break;
case LayoutToken::TRIANGLE_STRIP:
setPrimitive(Layout::kTriangleStrip_Primitive);
break;
case LayoutToken::TRIANGLES_ADJACENCY:
setPrimitive(Layout::kTrianglesAdjacency_Primitive);
break;
case LayoutToken::MAX_VERTICES:
setFlag(Layout::kMaxVertices_Flag);
maxVertices = this->layoutInt();
break;
case LayoutToken::INVOCATIONS:
setFlag(Layout::kInvocations_Flag);
invocations = this->layoutInt();
break;
default:
this->error(t, "'" + text + "' is not a valid layout qualifier");
break;
}
} else {
this->error(t, "'" + text + "' is not a valid layout qualifier");
}
if (this->checkNext(Token::Kind::TK_RPAREN)) {
break;
}
if (!this->expect(Token::Kind::TK_COMMA, "','")) {
break;
}
}
}
return Layout(flags, location, offset, binding, index, set, builtin, inputAttachmentIndex,
primitive, maxVertices, invocations);
}
/* layout? (UNIFORM | CONST | IN | OUT | INOUT | FLAT | NOPERSPECTIVE | INLINE)* */
Modifiers Parser::modifiers() {
Layout layout = this->layout();
int flags = 0;
for (;;) {
// TODO: handle duplicate / incompatible flags
int tokenFlag = parse_modifier_token(peek().fKind);
if (!tokenFlag) {
break;
}
flags |= tokenFlag;
this->nextToken();
}
return Modifiers(layout, flags);
}
Modifiers Parser::modifiersWithDefaults(int defaultFlags) {
Modifiers result = this->modifiers();
if (!result.fFlags) {
return Modifiers(result.fLayout, defaultFlags);
}
return result;
}
/* ifStatement | forStatement | doStatement | whileStatement | block | expression */
ASTNode::ID Parser::statement() {
Token start = this->nextToken();
AutoDepth depth(this);
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
this->pushback(start);
switch (start.fKind) {
case Token::Kind::TK_IF: // fall through
case Token::Kind::TK_STATIC_IF:
return this->ifStatement();
case Token::Kind::TK_FOR:
return this->forStatement();
case Token::Kind::TK_DO:
return this->doStatement();
case Token::Kind::TK_WHILE:
return this->whileStatement();
case Token::Kind::TK_SWITCH: // fall through
case Token::Kind::TK_STATIC_SWITCH:
return this->switchStatement();
case Token::Kind::TK_RETURN:
return this->returnStatement();
case Token::Kind::TK_BREAK:
return this->breakStatement();
case Token::Kind::TK_CONTINUE:
return this->continueStatement();
case Token::Kind::TK_DISCARD:
return this->discardStatement();
case Token::Kind::TK_LBRACE:
return this->block();
case Token::Kind::TK_SEMICOLON:
this->nextToken();
return this->createNode(start.fOffset, ASTNode::Kind::kBlock);
case Token::Kind::TK_HIGHP:
case Token::Kind::TK_MEDIUMP:
case Token::Kind::TK_LOWP:
case Token::Kind::TK_CONST:
case Token::Kind::TK_IDENTIFIER:
return this->varDeclarationsOrExpressionStatement();
default:
return this->expressionStatement();
}
}
/* IDENTIFIER(type) (LBRACKET intLiteral? RBRACKET)* QUESTION? */
ASTNode::ID Parser::type() {
Token type;
if (!this->expect(Token::Kind::TK_IDENTIFIER, "a type", &type)) {
return ASTNode::ID::Invalid();
}
if (!this->isType(this->text(type))) {
this->error(type, ("no type named '" + this->text(type) + "'").c_str());
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(type.fOffset, ASTNode::Kind::kType, this->text(type));
bool isArray = false;
while (this->checkNext(Token::Kind::TK_LBRACKET)) {
if (isArray) {
this->error(this->peek(), "multi-dimensional arrays are not supported");
return ASTNode::ID::Invalid();
}
if (this->peek().fKind != Token::Kind::TK_RBRACKET) {
SKSL_INT i;
if (this->intLiteral(&i)) {
this->addChild(result, this->createNode(this->peek().fOffset,
ASTNode::Kind::kInt, i));
} else {
return ASTNode::ID::Invalid();
}
} else {
this->createEmptyChild(result);
}
isArray = true;
this->expect(Token::Kind::TK_RBRACKET, "']'");
}
return result;
}
/* IDENTIFIER LBRACE
varDeclaration+
RBRACE (IDENTIFIER (LBRACKET expression? RBRACKET)*)? SEMICOLON */
ASTNode::ID Parser::interfaceBlock(Modifiers mods) {
Token name;
if (!this->expectIdentifier(&name)) {
return ASTNode::ID::Invalid();
}
if (peek().fKind != Token::Kind::TK_LBRACE) {
// we only get into interfaceBlock if we found a top-level identifier which was not a type.
// 99% of the time, the user was not actually intending to create an interface block, so
// it's better to report it as an unknown type
this->error(name, "no type named '" + this->text(name) + "'");
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(name.fOffset, ASTNode::Kind::kInterfaceBlock);
ASTNode::InterfaceBlockData id(mods, this->text(name), 0, "", 0);
this->nextToken();
while (this->peek().fKind != Token::Kind::TK_RBRACE) {
ASTNode::ID decl = this->varDeclarations();
if (!decl) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(decl);
++id.fDeclarationCount;
}
if (id.fDeclarationCount == 0) {
this->error(name, "interface block '" + this->text(name) +
"' must contain at least one member");
return ASTNode::ID::Invalid();
}
this->nextToken();
std::vector<ASTNode> sizes;
skstd::string_view instanceName;
Token instanceNameToken;
if (this->checkNext(Token::Kind::TK_IDENTIFIER, &instanceNameToken)) {
id.fInstanceName = this->text(instanceNameToken);
while (this->checkNext(Token::Kind::TK_LBRACKET)) {
if (id.fIsArray) {
this->error(this->peek(), "multi-dimensional arrays are not supported");
return false;
}
if (this->peek().fKind != Token::Kind::TK_RBRACKET) {
ASTNode::ID size = this->expression();
if (!size) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(size);
} else {
this->createEmptyChild(result);
}
this->expect(Token::Kind::TK_RBRACKET, "']'");
id.fIsArray = true;
}
instanceName = this->text(instanceNameToken);
}
getNode(result).setInterfaceBlockData(id);
this->expect(Token::Kind::TK_SEMICOLON, "';'");
return result;
}
/* IF LPAREN expression RPAREN statement (ELSE statement)? */
ASTNode::ID Parser::ifStatement() {
Token start;
bool isStatic = this->checkNext(Token::Kind::TK_STATIC_IF, &start);
if (!isStatic && !this->expect(Token::Kind::TK_IF, "'if'", &start)) {
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(start.fOffset, ASTNode::Kind::kIf, isStatic);
if (!this->expect(Token::Kind::TK_LPAREN, "'('")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID test = this->expression();
if (!test) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(test);
if (!this->expect(Token::Kind::TK_RPAREN, "')'")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID ifTrue = this->statement();
if (!ifTrue) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(ifTrue);
ASTNode::ID ifFalse;
if (this->checkNext(Token::Kind::TK_ELSE)) {
ifFalse = this->statement();
if (!ifFalse) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(ifFalse);
}
return result;
}
/* DO statement WHILE LPAREN expression RPAREN SEMICOLON */
ASTNode::ID Parser::doStatement() {
Token start;
if (!this->expect(Token::Kind::TK_DO, "'do'", &start)) {
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(start.fOffset, ASTNode::Kind::kDo);
ASTNode::ID statement = this->statement();
if (!statement) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(statement);
if (!this->expect(Token::Kind::TK_WHILE, "'while'")) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_LPAREN, "'('")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID test = this->expression();
if (!test) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(test);
if (!this->expect(Token::Kind::TK_RPAREN, "')'")) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_SEMICOLON, "';'")) {
return ASTNode::ID::Invalid();
}
return result;
}
/* WHILE LPAREN expression RPAREN STATEMENT */
ASTNode::ID Parser::whileStatement() {
Token start;
if (!this->expect(Token::Kind::TK_WHILE, "'while'", &start)) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_LPAREN, "'('")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(start.fOffset, ASTNode::Kind::kWhile);
ASTNode::ID test = this->expression();
if (!test) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(test);
if (!this->expect(Token::Kind::TK_RPAREN, "')'")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID statement = this->statement();
if (!statement) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(statement);
return result;
}
/* CASE expression COLON statement* */
ASTNode::ID Parser::switchCase() {
Token start;
if (!this->expect(Token::Kind::TK_CASE, "'case'", &start)) {
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(start.fOffset, ASTNode::Kind::kSwitchCase);
ASTNode::ID value = this->expression();
if (!value) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_COLON, "':'")) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(value);
while (this->peek().fKind != Token::Kind::TK_RBRACE &&
this->peek().fKind != Token::Kind::TK_CASE &&
this->peek().fKind != Token::Kind::TK_DEFAULT) {
ASTNode::ID s = this->statement();
if (!s) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(s);
}
return result;
}
/* SWITCH LPAREN expression RPAREN LBRACE switchCase* (DEFAULT COLON statement*)? RBRACE */
ASTNode::ID Parser::switchStatement() {
Token start;
bool isStatic = this->checkNext(Token::Kind::TK_STATIC_SWITCH, &start);
if (!isStatic && !this->expect(Token::Kind::TK_SWITCH, "'switch'", &start)) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_LPAREN, "'('")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID value = this->expression();
if (!value) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_RPAREN, "')'")) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_LBRACE, "'{'")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(start.fOffset, ASTNode::Kind::kSwitch, isStatic);
getNode(result).addChild(value);
while (this->peek().fKind == Token::Kind::TK_CASE) {
ASTNode::ID c = this->switchCase();
if (!c) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(c);
}
// Requiring default: to be last (in defiance of C and GLSL) was a deliberate decision. Other
// parts of the compiler may rely upon this assumption.
if (this->peek().fKind == Token::Kind::TK_DEFAULT) {
Token defaultStart;
SkAssertResult(this->expect(Token::Kind::TK_DEFAULT, "'default'", &defaultStart));
if (!this->expect(Token::Kind::TK_COLON, "':'")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID defaultCase = this->addChild(
result, this->createNode(defaultStart.fOffset, ASTNode::Kind::kSwitchCase));
this->createEmptyChild(defaultCase); // empty test to signify default case
while (this->peek().fKind != Token::Kind::TK_RBRACE) {
ASTNode::ID s = this->statement();
if (!s) {
return ASTNode::ID::Invalid();
}
getNode(defaultCase).addChild(s);
}
}
if (!this->expect(Token::Kind::TK_RBRACE, "'}'")) {
return ASTNode::ID::Invalid();
}
return result;
}
/* FOR LPAREN (declaration | expression)? SEMICOLON expression? SEMICOLON expression? RPAREN
STATEMENT */
ASTNode::ID Parser::forStatement() {
Token start;
if (!this->expect(Token::Kind::TK_FOR, "'for'", &start)) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_LPAREN, "'('")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(start.fOffset, ASTNode::Kind::kFor);
Token nextToken = this->peek();
if (nextToken.fKind == Token::Kind::TK_SEMICOLON) {
// An empty init-statement.
this->nextToken();
this->createEmptyChild(result);
} else {
// The init-statement must be an expression or variable declaration.
ASTNode::ID initializer = this->varDeclarationsOrExpressionStatement();
if (!initializer) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(initializer);
}
ASTNode::ID test;
if (this->peek().fKind != Token::Kind::TK_SEMICOLON) {
test = this->expression();
if (!test) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(test);
} else {
this->createEmptyChild(result);
}
if (!this->expect(Token::Kind::TK_SEMICOLON, "';'")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID next;
if (this->peek().fKind != Token::Kind::TK_RPAREN) {
next = this->expression();
if (!next) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(next);
} else {
this->createEmptyChild(result);
}
if (!this->expect(Token::Kind::TK_RPAREN, "')'")) {
return ASTNode::ID::Invalid();
}
ASTNode::ID statement = this->statement();
if (!statement) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(statement);
return result;
}
/* RETURN expression? SEMICOLON */
ASTNode::ID Parser::returnStatement() {
Token start;
if (!this->expect(Token::Kind::TK_RETURN, "'return'", &start)) {
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(start.fOffset, ASTNode::Kind::kReturn);
if (this->peek().fKind != Token::Kind::TK_SEMICOLON) {
ASTNode::ID expression = this->expression();
if (!expression) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(expression);
}
if (!this->expect(Token::Kind::TK_SEMICOLON, "';'")) {
return ASTNode::ID::Invalid();
}
return result;
}
/* BREAK SEMICOLON */
ASTNode::ID Parser::breakStatement() {
Token start;
if (!this->expect(Token::Kind::TK_BREAK, "'break'", &start)) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_SEMICOLON, "';'")) {
return ASTNode::ID::Invalid();
}
return this->createNode(start.fOffset, ASTNode::Kind::kBreak);
}
/* CONTINUE SEMICOLON */
ASTNode::ID Parser::continueStatement() {
Token start;
if (!this->expect(Token::Kind::TK_CONTINUE, "'continue'", &start)) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_SEMICOLON, "';'")) {
return ASTNode::ID::Invalid();
}
return this->createNode(start.fOffset, ASTNode::Kind::kContinue);
}
/* DISCARD SEMICOLON */
ASTNode::ID Parser::discardStatement() {
Token start;
if (!this->expect(Token::Kind::TK_DISCARD, "'continue'", &start)) {
return ASTNode::ID::Invalid();
}
if (!this->expect(Token::Kind::TK_SEMICOLON, "';'")) {
return ASTNode::ID::Invalid();
}
return this->createNode(start.fOffset, ASTNode::Kind::kDiscard);
}
/* LBRACE statement* RBRACE */
ASTNode::ID Parser::block() {
Token start;
if (!this->expect(Token::Kind::TK_LBRACE, "'{'", &start)) {
return ASTNode::ID::Invalid();
}
AutoDepth depth(this);
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(start.fOffset, ASTNode::Kind::kBlock);
for (;;) {
switch (this->peek().fKind) {
case Token::Kind::TK_RBRACE:
this->nextToken();
return result;
case Token::Kind::TK_END_OF_FILE:
this->error(this->peek(), "expected '}', but found end of file");
return ASTNode::ID::Invalid();
default: {
ASTNode::ID statement = this->statement();
if (!statement) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(statement);
}
}
}
return result;
}
/* expression SEMICOLON */
ASTNode::ID Parser::expressionStatement() {
ASTNode::ID expr = this->expression();
if (expr) {
if (this->expect(Token::Kind::TK_SEMICOLON, "';'")) {
return expr;
}
}
return ASTNode::ID::Invalid();
}
/* assignmentExpression (COMMA assignmentExpression)* */
ASTNode::ID Parser::expression() {
ASTNode::ID result = this->assignmentExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
Token t;
AutoDepth depth(this);
while (this->checkNext(Token::Kind::TK_COMMA, &t)) {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
ASTNode::ID right = this->assignmentExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(t.fOffset, ASTNode::Kind::kBinary,
Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
}
return result;
}
/* ternaryExpression ((EQEQ | STAREQ | SLASHEQ | PERCENTEQ | PLUSEQ | MINUSEQ | SHLEQ | SHREQ |
BITWISEANDEQ | BITWISEXOREQ | BITWISEOREQ | LOGICALANDEQ | LOGICALXOREQ | LOGICALOREQ)
assignmentExpression)*
*/
ASTNode::ID Parser::assignmentExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->ternaryExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
for (;;) {
switch (this->peek().fKind) {
case Token::Kind::TK_EQ: // fall through
case Token::Kind::TK_STAREQ: // fall through
case Token::Kind::TK_SLASHEQ: // fall through
case Token::Kind::TK_PERCENTEQ: // fall through
case Token::Kind::TK_PLUSEQ: // fall through
case Token::Kind::TK_MINUSEQ: // fall through
case Token::Kind::TK_SHLEQ: // fall through
case Token::Kind::TK_SHREQ: // fall through
case Token::Kind::TK_BITWISEANDEQ: // fall through
case Token::Kind::TK_BITWISEXOREQ: // fall through
case Token::Kind::TK_BITWISEOREQ: {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
Token t = this->nextToken();
ASTNode::ID right = this->assignmentExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset,
ASTNode::Kind::kBinary, Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
break;
}
default:
return result;
}
}
}
/* logicalOrExpression ('?' expression ':' assignmentExpression)? */
ASTNode::ID Parser::ternaryExpression() {
AutoDepth depth(this);
ASTNode::ID base = this->logicalOrExpression();
if (!base) {
return ASTNode::ID::Invalid();
}
if (this->checkNext(Token::Kind::TK_QUESTION)) {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
ASTNode::ID trueExpr = this->expression();
if (!trueExpr) {
return ASTNode::ID::Invalid();
}
if (this->expect(Token::Kind::TK_COLON, "':'")) {
ASTNode::ID falseExpr = this->assignmentExpression();
if (!falseExpr) {
return ASTNode::ID::Invalid();
}
ASTNode::ID ternary = this->createNode(getNode(base).fOffset, ASTNode::Kind::kTernary);
getNode(ternary).addChild(base);
getNode(ternary).addChild(trueExpr);
getNode(ternary).addChild(falseExpr);
return ternary;
}
return ASTNode::ID::Invalid();
}
return base;
}
/* logicalXorExpression (LOGICALOR logicalXorExpression)* */
ASTNode::ID Parser::logicalOrExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->logicalXorExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
Token t;
while (this->checkNext(Token::Kind::TK_LOGICALOR, &t)) {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
ASTNode::ID right = this->logicalXorExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset, ASTNode::Kind::kBinary,
Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
}
return result;
}
/* logicalAndExpression (LOGICALXOR logicalAndExpression)* */
ASTNode::ID Parser::logicalXorExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->logicalAndExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
Token t;
while (this->checkNext(Token::Kind::TK_LOGICALXOR, &t)) {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
ASTNode::ID right = this->logicalAndExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset, ASTNode::Kind::kBinary,
Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
}
return result;
}
/* bitwiseOrExpression (LOGICALAND bitwiseOrExpression)* */
ASTNode::ID Parser::logicalAndExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->bitwiseOrExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
Token t;
while (this->checkNext(Token::Kind::TK_LOGICALAND, &t)) {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
ASTNode::ID right = this->bitwiseOrExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset, ASTNode::Kind::kBinary,
Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
}
return result;
}
/* bitwiseXorExpression (BITWISEOR bitwiseXorExpression)* */
ASTNode::ID Parser::bitwiseOrExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->bitwiseXorExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
Token t;
while (this->checkNext(Token::Kind::TK_BITWISEOR, &t)) {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
ASTNode::ID right = this->bitwiseXorExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset, ASTNode::Kind::kBinary,
Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
}
return result;
}
/* bitwiseAndExpression (BITWISEXOR bitwiseAndExpression)* */
ASTNode::ID Parser::bitwiseXorExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->bitwiseAndExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
Token t;
while (this->checkNext(Token::Kind::TK_BITWISEXOR, &t)) {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
ASTNode::ID right = this->bitwiseAndExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset, ASTNode::Kind::kBinary,
Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
}
return result;
}
/* equalityExpression (BITWISEAND equalityExpression)* */
ASTNode::ID Parser::bitwiseAndExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->equalityExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
Token t;
while (this->checkNext(Token::Kind::TK_BITWISEAND, &t)) {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
ASTNode::ID right = this->equalityExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset, ASTNode::Kind::kBinary,
Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
}
return result;
}
/* relationalExpression ((EQEQ | NEQ) relationalExpression)* */
ASTNode::ID Parser::equalityExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->relationalExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
for (;;) {
switch (this->peek().fKind) {
case Token::Kind::TK_EQEQ: // fall through
case Token::Kind::TK_NEQ: {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
Token t = this->nextToken();
ASTNode::ID right = this->relationalExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset,
ASTNode::Kind::kBinary, Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
break;
}
default:
return result;
}
}
}
/* shiftExpression ((LT | GT | LTEQ | GTEQ) shiftExpression)* */
ASTNode::ID Parser::relationalExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->shiftExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
for (;;) {
switch (this->peek().fKind) {
case Token::Kind::TK_LT: // fall through
case Token::Kind::TK_GT: // fall through
case Token::Kind::TK_LTEQ: // fall through
case Token::Kind::TK_GTEQ: {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
Token t = this->nextToken();
ASTNode::ID right = this->shiftExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset,
ASTNode::Kind::kBinary, Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
break;
}
default:
return result;
}
}
}
/* additiveExpression ((SHL | SHR) additiveExpression)* */
ASTNode::ID Parser::shiftExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->additiveExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
for (;;) {
switch (this->peek().fKind) {
case Token::Kind::TK_SHL: // fall through
case Token::Kind::TK_SHR: {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
Token t = this->nextToken();
ASTNode::ID right = this->additiveExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset,
ASTNode::Kind::kBinary, Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
break;
}
default:
return result;
}
}
}
/* multiplicativeExpression ((PLUS | MINUS) multiplicativeExpression)* */
ASTNode::ID Parser::additiveExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->multiplicativeExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
for (;;) {
switch (this->peek().fKind) {
case Token::Kind::TK_PLUS: // fall through
case Token::Kind::TK_MINUS: {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
Token t = this->nextToken();
ASTNode::ID right = this->multiplicativeExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset,
ASTNode::Kind::kBinary, Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
break;
}
default:
return result;
}
}
}
/* unaryExpression ((STAR | SLASH | PERCENT) unaryExpression)* */
ASTNode::ID Parser::multiplicativeExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->unaryExpression();
if (!result) {
return ASTNode::ID::Invalid();
}
for (;;) {
switch (this->peek().fKind) {
case Token::Kind::TK_STAR: // fall through
case Token::Kind::TK_SLASH: // fall through
case Token::Kind::TK_PERCENT: {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
Token t = this->nextToken();
ASTNode::ID right = this->unaryExpression();
if (!right) {
return ASTNode::ID::Invalid();
}
ASTNode::ID newResult = this->createNode(getNode(result).fOffset,
ASTNode::Kind::kBinary, Operator(t.fKind));
getNode(newResult).addChild(result);
getNode(newResult).addChild(right);
result = newResult;
break;
}
default:
return result;
}
}
}
/* postfixExpression | (PLUS | MINUS | NOT | PLUSPLUS | MINUSMINUS) unaryExpression */
ASTNode::ID Parser::unaryExpression() {
AutoDepth depth(this);
switch (this->peek().fKind) {
case Token::Kind::TK_PLUS: // fall through
case Token::Kind::TK_MINUS: // fall through
case Token::Kind::TK_LOGICALNOT: // fall through
case Token::Kind::TK_BITWISENOT: // fall through
case Token::Kind::TK_PLUSPLUS: // fall through
case Token::Kind::TK_MINUSMINUS: {
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
Token t = this->nextToken();
ASTNode::ID expr = this->unaryExpression();
if (!expr) {
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->createNode(t.fOffset, ASTNode::Kind::kPrefix,
Operator(t.fKind));
getNode(result).addChild(expr);
return result;
}
default:
return this->postfixExpression();
}
}
/* term suffix* */
ASTNode::ID Parser::postfixExpression() {
AutoDepth depth(this);
ASTNode::ID result = this->term();
if (!result) {
return ASTNode::ID::Invalid();
}
for (;;) {
Token t = this->peek();
switch (t.fKind) {
case Token::Kind::TK_FLOAT_LITERAL:
if (this->text(t)[0] != '.') {
return result;
}
[[fallthrough]];
case Token::Kind::TK_LBRACKET:
case Token::Kind::TK_DOT:
case Token::Kind::TK_LPAREN:
case Token::Kind::TK_PLUSPLUS:
case Token::Kind::TK_MINUSMINUS:
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
result = this->suffix(result);
if (!result) {
return ASTNode::ID::Invalid();
}
break;
default:
return result;
}
}
}
/* LBRACKET expression? RBRACKET | DOT IDENTIFIER | LPAREN parameters RPAREN |
PLUSPLUS | MINUSMINUS | FLOAT_LITERAL [IDENTIFIER] */
ASTNode::ID Parser::suffix(ASTNode::ID base) {
SkASSERT(base);
Token next = this->nextToken();
AutoDepth depth(this);
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
switch (next.fKind) {
case Token::Kind::TK_LBRACKET: {
if (this->checkNext(Token::Kind::TK_RBRACKET)) {
ASTNode::ID result = this->createNode(next.fOffset, ASTNode::Kind::kIndex);
getNode(result).addChild(base);
return result;
}
ASTNode::ID e = this->expression();
if (!e) {
return ASTNode::ID::Invalid();
}
this->expect(Token::Kind::TK_RBRACKET, "']' to complete array access expression");
ASTNode::ID result = this->createNode(next.fOffset, ASTNode::Kind::kIndex);
getNode(result).addChild(base);
getNode(result).addChild(e);
return result;
}
case Token::Kind::TK_DOT: {
int offset = this->peek().fOffset;
skstd::string_view text;
if (this->identifier(&text)) {
ASTNode::ID result = this->createNode(offset, ASTNode::Kind::kField,
std::move(text));
getNode(result).addChild(base);
return result;
}
[[fallthrough]];
}
case Token::Kind::TK_FLOAT_LITERAL: {
// Swizzles that start with a constant number, e.g. '.000r', will be tokenized as
// floating point literals, possibly followed by an identifier. Handle that here.
skstd::string_view field = this->text(next);
SkASSERT(field[0] == '.');
field.remove_prefix(1);
for (auto iter = field.begin(); iter != field.end(); ++iter) {
if (*iter != '0' && *iter != '1') {
this->error(next, "invalid swizzle");
return ASTNode::ID::Invalid();
}
}
// use the next *raw* token so we don't ignore whitespace - we only care about
// identifiers that directly follow the float
Token id = this->nextRawToken();
if (id.fKind == Token::Kind::TK_IDENTIFIER) {
field = skstd::string_view(field.data(), field.length() + id.fLength);
} else {
this->pushback(id);
}
ASTNode::ID result = this->createNode(next.fOffset, ASTNode::Kind::kField, field);
getNode(result).addChild(base);
return result;
}
case Token::Kind::TK_LPAREN: {
ASTNode::ID result = this->createNode(next.fOffset, ASTNode::Kind::kCall);
getNode(result).addChild(base);
if (this->peek().fKind != Token::Kind::TK_RPAREN) {
for (;;) {
ASTNode::ID expr = this->assignmentExpression();
if (!expr) {
return ASTNode::ID::Invalid();
}
getNode(result).addChild(expr);
if (!this->checkNext(Token::Kind::TK_COMMA)) {
break;
}
}
}
this->expect(Token::Kind::TK_RPAREN, "')' to complete function parameters");
return result;
}
case Token::Kind::TK_PLUSPLUS: // fall through
case Token::Kind::TK_MINUSMINUS: {
ASTNode::ID result = this->createNode(next.fOffset, ASTNode::Kind::kPostfix,
Operator(next.fKind));
getNode(result).addChild(base);
return result;
}
default: {
this->error(next, "expected expression suffix, but found '" + this->text(next) + "'");
return ASTNode::ID::Invalid();
}
}
}
/* IDENTIFIER | intLiteral | floatLiteral | boolLiteral | '(' expression ')' */
ASTNode::ID Parser::term() {
Token t = this->peek();
switch (t.fKind) {
case Token::Kind::TK_IDENTIFIER: {
skstd::string_view text;
if (this->identifier(&text)) {
return this->createNode(t.fOffset, ASTNode::Kind::kIdentifier, std::move(text));
}
break;
}
case Token::Kind::TK_INT_LITERAL: {
SKSL_INT i;
if (this->intLiteral(&i)) {
return this->createNode(t.fOffset, ASTNode::Kind::kInt, i);
}
break;
}
case Token::Kind::TK_FLOAT_LITERAL: {
SKSL_FLOAT f;
if (this->floatLiteral(&f)) {
return this->createNode(t.fOffset, ASTNode::Kind::kFloat, f);
}
break;
}
case Token::Kind::TK_TRUE_LITERAL: // fall through
case Token::Kind::TK_FALSE_LITERAL: {
bool b;
if (this->boolLiteral(&b)) {
return this->createNode(t.fOffset, ASTNode::Kind::kBool, b);
}
break;
}
case Token::Kind::TK_LPAREN: {
this->nextToken();
AutoDepth depth(this);
if (!depth.increase()) {
return ASTNode::ID::Invalid();
}
ASTNode::ID result = this->expression();
if (result) {
this->expect(Token::Kind::TK_RPAREN, "')' to complete expression");
return result;
}
break;
}
default:
this->nextToken();
this->error(t.fOffset, "expected expression, but found '" + this->text(t) + "'");
}
return ASTNode::ID::Invalid();
}
/* INT_LITERAL */
bool Parser::intLiteral(SKSL_INT* dest) {
Token t;
if (!this->expect(Token::Kind::TK_INT_LITERAL, "integer literal", &t)) {
return false;
}
skstd::string_view s = this->text(t);
if (!SkSL::stoi(s, dest)) {
this->error(t, "integer is too large: " + s);
return false;
}
return true;
}
/* FLOAT_LITERAL */
bool Parser::floatLiteral(SKSL_FLOAT* dest) {
Token t;
if (!this->expect(Token::Kind::TK_FLOAT_LITERAL, "float literal", &t)) {
return false;
}
skstd::string_view s = this->text(t);
if (!SkSL::stod(s, dest)) {
this->error(t, "floating-point value is too large: " + s);
return false;
}
return true;
}
/* TRUE_LITERAL | FALSE_LITERAL */
bool Parser::boolLiteral(bool* dest) {
Token t = this->nextToken();
switch (t.fKind) {
case Token::Kind::TK_TRUE_LITERAL:
*dest = true;
return true;
case Token::Kind::TK_FALSE_LITERAL:
*dest = false;
return true;
default:
this->error(t, "expected 'true' or 'false', but found '" + this->text(t) + "'");
return false;
}
}
/* IDENTIFIER */
bool Parser::identifier(skstd::string_view* dest) {
Token t;
if (this->expect(Token::Kind::TK_IDENTIFIER, "identifier", &t)) {
*dest = this->text(t);
return true;
}
return false;
}
} // namespace SkSL