| // Copyright 2020 The Tint Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include "src/tint/reader/wgsl/parser_impl.h" |
| |
| #include <limits> |
| |
| #include "src/tint/ast/array.h" |
| #include "src/tint/ast/assignment_statement.h" |
| #include "src/tint/ast/bitcast_expression.h" |
| #include "src/tint/ast/break_statement.h" |
| #include "src/tint/ast/call_statement.h" |
| #include "src/tint/ast/continue_statement.h" |
| #include "src/tint/ast/discard_statement.h" |
| #include "src/tint/ast/external_texture.h" |
| #include "src/tint/ast/fallthrough_statement.h" |
| #include "src/tint/ast/id_attribute.h" |
| #include "src/tint/ast/if_statement.h" |
| #include "src/tint/ast/increment_decrement_statement.h" |
| #include "src/tint/ast/invariant_attribute.h" |
| #include "src/tint/ast/loop_statement.h" |
| #include "src/tint/ast/return_statement.h" |
| #include "src/tint/ast/stage_attribute.h" |
| #include "src/tint/ast/switch_statement.h" |
| #include "src/tint/ast/type_name.h" |
| #include "src/tint/ast/unary_op_expression.h" |
| #include "src/tint/ast/variable_decl_statement.h" |
| #include "src/tint/ast/vector.h" |
| #include "src/tint/ast/workgroup_attribute.h" |
| #include "src/tint/reader/wgsl/lexer.h" |
| #include "src/tint/sem/depth_texture.h" |
| #include "src/tint/sem/external_texture.h" |
| #include "src/tint/sem/multisampled_texture.h" |
| #include "src/tint/sem/sampled_texture.h" |
| |
| namespace tint::reader::wgsl { |
| namespace { |
| |
| template <typename T> |
| using Expect = ParserImpl::Expect<T>; |
| |
| template <typename T> |
| using Maybe = ParserImpl::Maybe<T>; |
| |
| /// Controls the maximum number of times we'll call into the sync() and |
| /// unary_expression() functions from themselves. This is to guard against stack |
| /// overflow when there is an excessive number of blocks. |
| constexpr uint32_t kMaxParseDepth = 128; |
| |
| /// The maximum number of tokens to look ahead to try and sync the |
| /// parser on error. |
| constexpr size_t const kMaxResynchronizeLookahead = 32; |
| |
| const char kVertexStage[] = "vertex"; |
| const char kFragmentStage[] = "fragment"; |
| const char kComputeStage[] = "compute"; |
| |
| const char kReadAccess[] = "read"; |
| const char kWriteAccess[] = "write"; |
| const char kReadWriteAccess[] = "read_write"; |
| |
| ast::Builtin ident_to_builtin(std::string_view str) { |
| if (str == "position") { |
| return ast::Builtin::kPosition; |
| } |
| if (str == "vertex_index") { |
| return ast::Builtin::kVertexIndex; |
| } |
| if (str == "instance_index") { |
| return ast::Builtin::kInstanceIndex; |
| } |
| if (str == "front_facing") { |
| return ast::Builtin::kFrontFacing; |
| } |
| if (str == "frag_depth") { |
| return ast::Builtin::kFragDepth; |
| } |
| if (str == "local_invocation_id") { |
| return ast::Builtin::kLocalInvocationId; |
| } |
| if (str == "local_invocation_idx" || str == "local_invocation_index") { |
| return ast::Builtin::kLocalInvocationIndex; |
| } |
| if (str == "global_invocation_id") { |
| return ast::Builtin::kGlobalInvocationId; |
| } |
| if (str == "workgroup_id") { |
| return ast::Builtin::kWorkgroupId; |
| } |
| if (str == "num_workgroups") { |
| return ast::Builtin::kNumWorkgroups; |
| } |
| if (str == "sample_index") { |
| return ast::Builtin::kSampleIndex; |
| } |
| if (str == "sample_mask") { |
| return ast::Builtin::kSampleMask; |
| } |
| return ast::Builtin::kNone; |
| } |
| |
| const char kBindingAttribute[] = "binding"; |
| const char kBuiltinAttribute[] = "builtin"; |
| const char kGroupAttribute[] = "group"; |
| const char kIdAttribute[] = "id"; |
| const char kInterpolateAttribute[] = "interpolate"; |
| const char kInvariantAttribute[] = "invariant"; |
| const char kLocationAttribute[] = "location"; |
| const char kSizeAttribute[] = "size"; |
| const char kAlignAttribute[] = "align"; |
| const char kStageAttribute[] = "stage"; |
| const char kWorkgroupSizeAttribute[] = "workgroup_size"; |
| |
| // https://gpuweb.github.io/gpuweb/wgsl.html#reserved-keywords |
| bool is_reserved(Token t) { |
| return t == "asm" || t == "bf16" || t == "const" || t == "do" || t == "enum" || t == "f64" || |
| t == "handle" || t == "i8" || t == "i16" || t == "i64" || t == "mat" || |
| t == "premerge" || t == "regardless" || t == "typedef" || t == "u8" || t == "u16" || |
| t == "u64" || t == "unless" || t == "using" || t == "vec" || t == "void" || t == "while"; |
| } |
| |
| /// Enter-exit counters for block token types. |
| /// Used by sync_to() to skip over closing block tokens that were opened during |
| /// the forward scan. |
| struct BlockCounters { |
| int brace = 0; // { } |
| int bracket = 0; // [ ] |
| int paren = 0; // ( ) |
| |
| /// @return the current enter-exit depth for the given block token type. If |
| /// `t` is not a block token type, then 0 is always returned. |
| int consume(const Token& t) { |
| if (t.Is(Token::Type::kBraceLeft)) { |
| return brace++; |
| } |
| if (t.Is(Token::Type::kBraceRight)) { |
| return brace--; |
| } |
| if (t.Is(Token::Type::kBracketLeft)) { |
| return bracket++; |
| } |
| if (t.Is(Token::Type::kBracketRight)) { |
| return bracket--; |
| } |
| if (t.Is(Token::Type::kParenLeft)) { |
| return paren++; |
| } |
| if (t.Is(Token::Type::kParenRight)) { |
| return paren--; |
| } |
| return 0; |
| } |
| }; |
| } // namespace |
| |
| /// RAII helper that combines a Source on construction with the last token's |
| /// source when implicitly converted to `Source`. |
| class ParserImpl::MultiTokenSource { |
| public: |
| /// Constructor that starts with Source at the current peek position |
| /// @param parser the parser |
| explicit MultiTokenSource(ParserImpl* parser) |
| : MultiTokenSource(parser, parser->peek().source().Begin()) {} |
| |
| /// Constructor that starts with the input `start` Source |
| /// @param parser the parser |
| /// @param start the start source of the range |
| MultiTokenSource(ParserImpl* parser, const Source& start) : parser_(parser), start_(start) {} |
| |
| /// Implicit conversion to Source that returns the combined source from start |
| /// to the current last token's source. |
| operator Source() const { |
| Source end = parser_->last_token().source().End(); |
| if (end < start_) { |
| end = start_; |
| } |
| return Source::Combine(start_, end); |
| } |
| |
| private: |
| ParserImpl* parser_; |
| Source start_; |
| }; |
| |
| ParserImpl::TypedIdentifier::TypedIdentifier() = default; |
| |
| ParserImpl::TypedIdentifier::TypedIdentifier(const TypedIdentifier&) = default; |
| |
| ParserImpl::TypedIdentifier::TypedIdentifier(const ast::Type* type_in, |
| std::string name_in, |
| Source source_in) |
| : type(type_in), name(std::move(name_in)), source(std::move(source_in)) {} |
| |
| ParserImpl::TypedIdentifier::~TypedIdentifier() = default; |
| |
| ParserImpl::FunctionHeader::FunctionHeader() = default; |
| |
| ParserImpl::FunctionHeader::FunctionHeader(const FunctionHeader&) = default; |
| |
| ParserImpl::FunctionHeader::FunctionHeader(Source src, |
| std::string n, |
| ast::VariableList p, |
| const ast::Type* ret_ty, |
| ast::AttributeList ret_attrs) |
| : source(src), name(n), params(p), return_type(ret_ty), return_type_attributes(ret_attrs) {} |
| |
| ParserImpl::FunctionHeader::~FunctionHeader() = default; |
| |
| ParserImpl::FunctionHeader& ParserImpl::FunctionHeader::operator=(const FunctionHeader& rhs) = |
| default; |
| |
| ParserImpl::VarDeclInfo::VarDeclInfo() = default; |
| |
| ParserImpl::VarDeclInfo::VarDeclInfo(const VarDeclInfo&) = default; |
| |
| ParserImpl::VarDeclInfo::VarDeclInfo(Source source_in, |
| std::string name_in, |
| ast::StorageClass storage_class_in, |
| ast::Access access_in, |
| const ast::Type* type_in) |
| : source(std::move(source_in)), |
| name(std::move(name_in)), |
| storage_class(storage_class_in), |
| access(access_in), |
| type(type_in) {} |
| |
| ParserImpl::VarDeclInfo::~VarDeclInfo() = default; |
| |
| ParserImpl::ParserImpl(Source::File const* file) : lexer_(std::make_unique<Lexer>(file)) {} |
| |
| ParserImpl::~ParserImpl() = default; |
| |
| ParserImpl::Failure::Errored ParserImpl::add_error(const Source& source, |
| std::string_view err, |
| std::string_view use) { |
| std::stringstream msg; |
| msg << err; |
| if (!use.empty()) { |
| msg << " for " << use; |
| } |
| add_error(source, msg.str()); |
| return Failure::kErrored; |
| } |
| |
| ParserImpl::Failure::Errored ParserImpl::add_error(const Token& t, const std::string& err) { |
| add_error(t.source(), err); |
| return Failure::kErrored; |
| } |
| |
| ParserImpl::Failure::Errored ParserImpl::add_error(const Source& source, const std::string& err) { |
| if (silence_errors_ == 0) { |
| builder_.Diagnostics().add_error(diag::System::Reader, err, source); |
| } |
| return Failure::kErrored; |
| } |
| |
| void ParserImpl::deprecated(const Source& source, const std::string& msg) { |
| builder_.Diagnostics().add_warning(diag::System::Reader, |
| "use of deprecated language feature: " + msg, source); |
| } |
| |
| Token ParserImpl::next() { |
| if (!token_queue_.empty()) { |
| auto t = token_queue_.front(); |
| token_queue_.pop_front(); |
| last_token_ = t; |
| return last_token_; |
| } |
| last_token_ = lexer_->next(); |
| return last_token_; |
| } |
| |
| Token ParserImpl::peek(size_t idx) { |
| while (token_queue_.size() < (idx + 1)) { |
| token_queue_.push_back(lexer_->next()); |
| } |
| return token_queue_[idx]; |
| } |
| |
| bool ParserImpl::peek_is(Token::Type tok, size_t idx) { |
| return peek(idx).Is(tok); |
| } |
| |
| Token ParserImpl::last_token() const { |
| return last_token_; |
| } |
| |
| bool ParserImpl::Parse() { |
| translation_unit(); |
| return !has_error(); |
| } |
| |
| // translation_unit |
| // : enable_directive* global_decl* EOF |
| void ParserImpl::translation_unit() { |
| bool after_global_decl = false; |
| while (continue_parsing()) { |
| auto p = peek(); |
| if (p.IsEof()) { |
| break; |
| } |
| |
| auto ed = enable_directive(); |
| if (ed.matched) { |
| if (after_global_decl) { |
| add_error(p, "enable directives must come before all global declarations"); |
| } |
| } else if (ed.errored) { |
| // Found a invalid enable directive. |
| continue; |
| } else { |
| auto gd = global_decl(); |
| |
| if (gd.matched) { |
| after_global_decl = true; |
| } |
| |
| if (!gd.matched && !gd.errored) { |
| add_error(p, "unexpected token"); |
| } |
| } |
| |
| if (builder_.Diagnostics().error_count() >= max_errors_) { |
| add_error(Source{{}, p.source().file}, |
| "stopping after " + std::to_string(max_errors_) + " errors"); |
| break; |
| } |
| } |
| } |
| |
| // enable_directive |
| // : enable name SEMICLON |
| Maybe<bool> ParserImpl::enable_directive() { |
| auto decl = sync(Token::Type::kSemicolon, [&]() -> Maybe<bool> { |
| if (!match(Token::Type::kEnable)) { |
| return Failure::kNoMatch; |
| } |
| |
| // Match the extension name. |
| Expect<std::string> name = {""}; |
| auto t = peek(); |
| if (t.IsIdentifier()) { |
| synchronized_ = true; |
| next(); |
| name = {t.to_str(), t.source()}; |
| } else if (t.Is(Token::Type::kF16)) { |
| // `f16` is a valid extension name and also a keyword |
| synchronized_ = true; |
| next(); |
| name = {"f16", t.source()}; |
| } else if (handle_error(t)) { |
| // The token might itself be an error. |
| return Failure::kErrored; |
| } else { |
| // Failed to match an extension name. |
| synchronized_ = false; |
| return add_error(t.source(), "invalid extension name"); |
| } |
| |
| if (!expect("enable directive", Token::Type::kSemicolon)) { |
| return Failure::kErrored; |
| } |
| |
| auto extension = ast::ParseExtension(name.value); |
| if (extension == ast::Extension::kNone) { |
| return add_error(name.source, "unsupported extension: '" + name.value + "'"); |
| } |
| builder_.AST().AddEnable(create<ast::Enable>(name.source, extension)); |
| |
| return true; |
| }); |
| |
| if (decl.errored) { |
| return Failure::kErrored; |
| } |
| if (decl.matched) { |
| return true; |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| // global_decl |
| // : SEMICOLON |
| // | global_variable_decl SEMICLON |
| // | global_constant_decl SEMICOLON |
| // | type_alias SEMICOLON |
| // | struct_decl |
| // | function_decl |
| Maybe<bool> ParserImpl::global_decl() { |
| if (match(Token::Type::kSemicolon) || match(Token::Type::kEOF)) { |
| return true; |
| } |
| |
| bool errored = false; |
| |
| auto attrs = attribute_list(); |
| if (attrs.errored) { |
| errored = true; |
| } |
| if (!continue_parsing()) { |
| return Failure::kErrored; |
| } |
| |
| auto decl = sync(Token::Type::kSemicolon, [&]() -> Maybe<bool> { |
| auto gv = global_variable_decl(attrs.value); |
| if (gv.errored) { |
| return Failure::kErrored; |
| } |
| if (gv.matched) { |
| if (!expect("variable declaration", Token::Type::kSemicolon)) { |
| return Failure::kErrored; |
| } |
| |
| builder_.AST().AddGlobalVariable(gv.value); |
| return true; |
| } |
| |
| auto gc = global_constant_decl(attrs.value); |
| if (gc.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (gc.matched) { |
| if (!expect("let declaration", Token::Type::kSemicolon)) { |
| return Failure::kErrored; |
| } |
| |
| builder_.AST().AddGlobalVariable(gc.value); |
| return true; |
| } |
| |
| auto ta = type_alias(); |
| if (ta.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (ta.matched) { |
| if (!expect("type alias", Token::Type::kSemicolon)) { |
| return Failure::kErrored; |
| } |
| |
| builder_.AST().AddTypeDecl(ta.value); |
| return true; |
| } |
| |
| auto str = struct_decl(); |
| if (str.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (str.matched) { |
| builder_.AST().AddTypeDecl(str.value); |
| return true; |
| } |
| |
| return Failure::kNoMatch; |
| }); |
| |
| if (decl.errored) { |
| errored = true; |
| } |
| if (decl.matched) { |
| return expect_attributes_consumed(attrs.value); |
| } |
| |
| auto func = function_decl(attrs.value); |
| if (func.errored) { |
| errored = true; |
| } |
| if (func.matched) { |
| builder_.AST().AddFunction(func.value); |
| return true; |
| } |
| |
| if (errored) { |
| return Failure::kErrored; |
| } |
| |
| // Invalid syntax found - try and determine the best error message |
| |
| // We have attributes parsed, but nothing to consume them? |
| if (attrs.value.size() > 0) { |
| return add_error(next(), "expected declaration after attributes"); |
| } |
| |
| // We have a statement outside of a function? |
| auto t = peek(); |
| auto stat = without_error([&] { return statement(); }); |
| if (stat.matched) { |
| // Attempt to jump to the next '}' - the function might have just been |
| // missing an opening line. |
| sync_to(Token::Type::kBraceRight, true); |
| return add_error(t, "statement found outside of function body"); |
| } |
| if (!stat.errored) { |
| // No match, no error - the parser might not have progressed. |
| // Ensure we always make _some_ forward progress. |
| next(); |
| } |
| |
| // The token might itself be an error. |
| if (handle_error(t)) { |
| return Failure::kErrored; |
| } |
| |
| // Exhausted all attempts to make sense of where we're at. |
| // Return a no-match |
| |
| return Failure::kNoMatch; |
| } |
| |
| // global_variable_decl |
| // : variable_attribute_list* variable_decl |
| // | variable_attribute_list* variable_decl EQUAL const_expr |
| Maybe<const ast::Variable*> ParserImpl::global_variable_decl(ast::AttributeList& attrs) { |
| auto decl = variable_decl(); |
| if (decl.errored) { |
| return Failure::kErrored; |
| } |
| if (!decl.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| const ast::Expression* constructor = nullptr; |
| if (match(Token::Type::kEqual)) { |
| auto expr = expect_const_expr(); |
| if (expr.errored) { |
| return Failure::kErrored; |
| } |
| constructor = expr.value; |
| } |
| |
| return create<ast::Variable>(decl->source, // source |
| builder_.Symbols().Register(decl->name), // symbol |
| decl->storage_class, // storage class |
| decl->access, // access control |
| decl->type, // type |
| false, // is_const |
| false, // is_overridable |
| constructor, // constructor |
| std::move(attrs)); // attributes |
| } |
| |
| // global_constant_decl : |
| // | LET (ident | variable_ident_decl) global_const_initializer |
| // | attribute* override (ident | variable_ident_decl) (equal expression)? |
| // global_const_initializer |
| // : EQUAL const_expr |
| Maybe<const ast::Variable*> ParserImpl::global_constant_decl(ast::AttributeList& attrs) { |
| bool is_overridable = false; |
| const char* use = nullptr; |
| if (match(Token::Type::kLet)) { |
| use = "let declaration"; |
| } else if (match(Token::Type::kOverride)) { |
| use = "override declaration"; |
| is_overridable = true; |
| } else { |
| return Failure::kNoMatch; |
| } |
| |
| auto decl = expect_variable_ident_decl(use, /* allow_inferred = */ true); |
| if (decl.errored) { |
| return Failure::kErrored; |
| } |
| |
| const ast::Expression* initializer = nullptr; |
| if (match(Token::Type::kEqual)) { |
| auto init = expect_const_expr(); |
| if (init.errored) { |
| return Failure::kErrored; |
| } |
| initializer = std::move(init.value); |
| } |
| |
| return create<ast::Variable>(decl->source, // source |
| builder_.Symbols().Register(decl->name), // symbol |
| ast::StorageClass::kNone, // storage class |
| ast::Access::kUndefined, // access control |
| decl->type, // type |
| true, // is_const |
| is_overridable, // is_overridable |
| initializer, // constructor |
| std::move(attrs)); // attributes |
| } |
| |
| // variable_decl |
| // : VAR variable_qualifier? variable_ident_decl |
| Maybe<ParserImpl::VarDeclInfo> ParserImpl::variable_decl(bool allow_inferred) { |
| Source source; |
| if (!match(Token::Type::kVar, &source)) { |
| return Failure::kNoMatch; |
| } |
| |
| VariableQualifier vq; |
| auto explicit_vq = variable_qualifier(); |
| if (explicit_vq.errored) { |
| return Failure::kErrored; |
| } |
| if (explicit_vq.matched) { |
| vq = explicit_vq.value; |
| } |
| |
| auto decl = expect_variable_ident_decl("variable declaration", allow_inferred); |
| if (decl.errored) { |
| return Failure::kErrored; |
| } |
| |
| return VarDeclInfo{decl->source, decl->name, vq.storage_class, vq.access, decl->type}; |
| } |
| |
| // texture_samplers |
| // : sampler |
| // | depth_texture |
| // | sampled_texture LESS_THAN type_decl GREATER_THAN |
| // | multisampled_texture LESS_THAN type_decl GREATER_THAN |
| // | storage_texture LESS_THAN texel_format |
| // COMMA access GREATER_THAN |
| Maybe<const ast::Type*> ParserImpl::texture_samplers() { |
| auto type = sampler(); |
| if (type.matched) { |
| return type; |
| } |
| |
| type = depth_texture(); |
| if (type.matched) { |
| return type; |
| } |
| |
| type = external_texture(); |
| if (type.matched) { |
| return type.value; |
| } |
| |
| auto source_range = make_source_range(); |
| |
| auto dim = sampled_texture(); |
| if (dim.matched) { |
| const char* use = "sampled texture type"; |
| |
| auto subtype = expect_lt_gt_block(use, [&] { return expect_type(use); }); |
| if (subtype.errored) { |
| return Failure::kErrored; |
| } |
| |
| return builder_.ty.sampled_texture(source_range, dim.value, subtype.value); |
| } |
| |
| auto ms_dim = multisampled_texture(); |
| if (ms_dim.matched) { |
| const char* use = "multisampled texture type"; |
| |
| auto subtype = expect_lt_gt_block(use, [&] { return expect_type(use); }); |
| if (subtype.errored) { |
| return Failure::kErrored; |
| } |
| |
| return builder_.ty.multisampled_texture(source_range, ms_dim.value, subtype.value); |
| } |
| |
| auto storage = storage_texture(); |
| if (storage.matched) { |
| const char* use = "storage texture type"; |
| using StorageTextureInfo = std::pair<tint::ast::TexelFormat, tint::ast::Access>; |
| auto params = expect_lt_gt_block(use, [&]() -> Expect<StorageTextureInfo> { |
| auto format = expect_texel_format(use); |
| if (format.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (!expect("access control", Token::Type::kComma)) { |
| return Failure::kErrored; |
| } |
| |
| auto access = expect_access("access control"); |
| if (access.errored) { |
| return Failure::kErrored; |
| } |
| |
| return std::make_pair(format.value, access.value); |
| }); |
| |
| if (params.errored) { |
| return Failure::kErrored; |
| } |
| |
| return builder_.ty.storage_texture(source_range, storage.value, params->first, |
| params->second); |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| // sampler |
| // : SAMPLER |
| // | SAMPLER_COMPARISON |
| Maybe<const ast::Type*> ParserImpl::sampler() { |
| Source source; |
| if (match(Token::Type::kSampler, &source)) { |
| return builder_.ty.sampler(source, ast::SamplerKind::kSampler); |
| } |
| |
| if (match(Token::Type::kComparisonSampler, &source)) { |
| return builder_.ty.sampler(source, ast::SamplerKind::kComparisonSampler); |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| // sampled_texture |
| // : TEXTURE_SAMPLED_1D |
| // | TEXTURE_SAMPLED_2D |
| // | TEXTURE_SAMPLED_2D_ARRAY |
| // | TEXTURE_SAMPLED_3D |
| // | TEXTURE_SAMPLED_CUBE |
| // | TEXTURE_SAMPLED_CUBE_ARRAY |
| Maybe<const ast::TextureDimension> ParserImpl::sampled_texture() { |
| if (match(Token::Type::kTextureSampled1d)) { |
| return ast::TextureDimension::k1d; |
| } |
| |
| if (match(Token::Type::kTextureSampled2d)) { |
| return ast::TextureDimension::k2d; |
| } |
| |
| if (match(Token::Type::kTextureSampled2dArray)) { |
| return ast::TextureDimension::k2dArray; |
| } |
| |
| if (match(Token::Type::kTextureSampled3d)) { |
| return ast::TextureDimension::k3d; |
| } |
| |
| if (match(Token::Type::kTextureSampledCube)) { |
| return ast::TextureDimension::kCube; |
| } |
| |
| if (match(Token::Type::kTextureSampledCubeArray)) { |
| return ast::TextureDimension::kCubeArray; |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| // external_texture |
| // : TEXTURE_EXTERNAL |
| Maybe<const ast::Type*> ParserImpl::external_texture() { |
| Source source; |
| if (match(Token::Type::kTextureExternal, &source)) { |
| return builder_.ty.external_texture(source); |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| // multisampled_texture |
| // : TEXTURE_MULTISAMPLED_2D |
| Maybe<const ast::TextureDimension> ParserImpl::multisampled_texture() { |
| if (match(Token::Type::kTextureMultisampled2d)) { |
| return ast::TextureDimension::k2d; |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| // storage_texture |
| // : TEXTURE_STORAGE_1D |
| // | TEXTURE_STORAGE_2D |
| // | TEXTURE_STORAGE_2D_ARRAY |
| // | TEXTURE_STORAGE_3D |
| Maybe<const ast::TextureDimension> ParserImpl::storage_texture() { |
| if (match(Token::Type::kTextureStorage1d)) { |
| return ast::TextureDimension::k1d; |
| } |
| if (match(Token::Type::kTextureStorage2d)) { |
| return ast::TextureDimension::k2d; |
| } |
| if (match(Token::Type::kTextureStorage2dArray)) { |
| return ast::TextureDimension::k2dArray; |
| } |
| if (match(Token::Type::kTextureStorage3d)) { |
| return ast::TextureDimension::k3d; |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| // depth_texture |
| // : TEXTURE_DEPTH_2D |
| // | TEXTURE_DEPTH_2D_ARRAY |
| // | TEXTURE_DEPTH_CUBE |
| // | TEXTURE_DEPTH_CUBE_ARRAY |
| // | TEXTURE_DEPTH_MULTISAMPLED_2D |
| Maybe<const ast::Type*> ParserImpl::depth_texture() { |
| Source source; |
| if (match(Token::Type::kTextureDepth2d, &source)) { |
| return builder_.ty.depth_texture(source, ast::TextureDimension::k2d); |
| } |
| if (match(Token::Type::kTextureDepth2dArray, &source)) { |
| return builder_.ty.depth_texture(source, ast::TextureDimension::k2dArray); |
| } |
| if (match(Token::Type::kTextureDepthCube, &source)) { |
| return builder_.ty.depth_texture(source, ast::TextureDimension::kCube); |
| } |
| if (match(Token::Type::kTextureDepthCubeArray, &source)) { |
| return builder_.ty.depth_texture(source, ast::TextureDimension::kCubeArray); |
| } |
| if (match(Token::Type::kTextureDepthMultisampled2d, &source)) { |
| return builder_.ty.depth_multisampled_texture(source, ast::TextureDimension::k2d); |
| } |
| return Failure::kNoMatch; |
| } |
| |
| // texel_format |
| // : 'rgba8unorm' |
| // | 'rgba8snorm' |
| // | 'rgba8uint' |
| // | 'rgba8sint' |
| // | 'rgba16uint' |
| // | 'rgba16sint' |
| // | 'rgba16float' |
| // | 'r32uint' |
| // | 'r32sint' |
| // | 'r32float' |
| // | 'rg32uint' |
| // | 'rg32sint' |
| // | 'rg32float' |
| // | 'rgba32uint' |
| // | 'rgba32sint' |
| // | 'rgba32float' |
| Expect<ast::TexelFormat> ParserImpl::expect_texel_format(std::string_view use) { |
| auto t = next(); |
| if (t == "rgba8unorm") { |
| return ast::TexelFormat::kRgba8Unorm; |
| } |
| if (t == "rgba8snorm") { |
| return ast::TexelFormat::kRgba8Snorm; |
| } |
| if (t == "rgba8uint") { |
| return ast::TexelFormat::kRgba8Uint; |
| } |
| if (t == "rgba8sint") { |
| return ast::TexelFormat::kRgba8Sint; |
| } |
| if (t == "rgba16uint") { |
| return ast::TexelFormat::kRgba16Uint; |
| } |
| if (t == "rgba16sint") { |
| return ast::TexelFormat::kRgba16Sint; |
| } |
| if (t == "rgba16float") { |
| return ast::TexelFormat::kRgba16Float; |
| } |
| if (t == "r32uint") { |
| return ast::TexelFormat::kR32Uint; |
| } |
| if (t == "r32sint") { |
| return ast::TexelFormat::kR32Sint; |
| } |
| if (t == "r32float") { |
| return ast::TexelFormat::kR32Float; |
| } |
| if (t == "rg32uint") { |
| return ast::TexelFormat::kRg32Uint; |
| } |
| if (t == "rg32sint") { |
| return ast::TexelFormat::kRg32Sint; |
| } |
| if (t == "rg32float") { |
| return ast::TexelFormat::kRg32Float; |
| } |
| if (t == "rgba32uint") { |
| return ast::TexelFormat::kRgba32Uint; |
| } |
| if (t == "rgba32sint") { |
| return ast::TexelFormat::kRgba32Sint; |
| } |
| if (t == "rgba32float") { |
| return ast::TexelFormat::kRgba32Float; |
| } |
| return add_error(t.source(), "invalid format", use); |
| } |
| |
| // variable_ident_decl |
| // : IDENT COLON type_decl |
| Expect<ParserImpl::TypedIdentifier> ParserImpl::expect_variable_ident_decl(std::string_view use, |
| bool allow_inferred) { |
| auto ident = expect_ident(use); |
| if (ident.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (allow_inferred && !peek_is(Token::Type::kColon)) { |
| return TypedIdentifier{nullptr, ident.value, ident.source}; |
| } |
| |
| if (!expect(use, Token::Type::kColon)) { |
| return Failure::kErrored; |
| } |
| |
| auto t = peek(); |
| auto type = type_decl(); |
| if (type.errored) { |
| return Failure::kErrored; |
| } |
| if (!type.matched) { |
| return add_error(t.source(), "invalid type", use); |
| } |
| |
| return TypedIdentifier{type.value, ident.value, ident.source}; |
| } |
| |
| Expect<ast::Access> ParserImpl::expect_access(std::string_view use) { |
| auto ident = expect_ident(use); |
| if (ident.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (ident.value == kReadAccess) { |
| return {ast::Access::kRead, ident.source}; |
| } |
| if (ident.value == kWriteAccess) { |
| return {ast::Access::kWrite, ident.source}; |
| } |
| if (ident.value == kReadWriteAccess) { |
| return {ast::Access::kReadWrite, ident.source}; |
| } |
| |
| return add_error(ident.source, "invalid value for access control"); |
| } |
| |
| // variable_qualifier |
| // : LESS_THAN storage_class (COMMA access_mode)? GREATER_THAN |
| Maybe<ParserImpl::VariableQualifier> ParserImpl::variable_qualifier() { |
| if (!peek_is(Token::Type::kLessThan)) { |
| return Failure::kNoMatch; |
| } |
| |
| auto* use = "variable declaration"; |
| auto vq = expect_lt_gt_block(use, [&]() -> Expect<VariableQualifier> { |
| auto source = make_source_range(); |
| auto sc = expect_storage_class(use); |
| if (sc.errored) { |
| return Failure::kErrored; |
| } |
| if (match(Token::Type::kComma)) { |
| auto ac = expect_access(use); |
| if (ac.errored) { |
| return Failure::kErrored; |
| } |
| return VariableQualifier{sc.value, ac.value}; |
| } |
| return Expect<VariableQualifier>{VariableQualifier{sc.value, ast::Access::kUndefined}, |
| source}; |
| }); |
| |
| if (vq.errored) { |
| return Failure::kErrored; |
| } |
| |
| return vq; |
| } |
| |
| // type_alias |
| // : TYPE IDENT EQUAL type_decl |
| Maybe<const ast::Alias*> ParserImpl::type_alias() { |
| if (!peek_is(Token::Type::kType)) { |
| return Failure::kNoMatch; |
| } |
| |
| auto t = next(); |
| const char* use = "type alias"; |
| |
| auto name = expect_ident(use); |
| if (name.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (!expect(use, Token::Type::kEqual)) { |
| return Failure::kErrored; |
| } |
| |
| auto type = type_decl(); |
| if (type.errored) { |
| return Failure::kErrored; |
| } |
| if (!type.matched) { |
| return add_error(peek(), "invalid type alias"); |
| } |
| |
| return builder_.ty.alias(make_source_range_from(t.source()), name.value, type.value); |
| } |
| |
| // type_decl |
| // : IDENTIFIER |
| // | BOOL |
| // | FLOAT32 |
| // | INT32 |
| // | UINT32 |
| // | VEC2 LESS_THAN type_decl GREATER_THAN |
| // | VEC3 LESS_THAN type_decl GREATER_THAN |
| // | VEC4 LESS_THAN type_decl GREATER_THAN |
| // | PTR LESS_THAN storage_class, type_decl (COMMA access_mode)? GREATER_THAN |
| // | array_attribute_list* ARRAY LESS_THAN type_decl COMMA |
| // INT_LITERAL GREATER_THAN |
| // | array_attribute_list* ARRAY LESS_THAN type_decl |
| // GREATER_THAN |
| // | MAT2x2 LESS_THAN type_decl GREATER_THAN |
| // | MAT2x3 LESS_THAN type_decl GREATER_THAN |
| // | MAT2x4 LESS_THAN type_decl GREATER_THAN |
| // | MAT3x2 LESS_THAN type_decl GREATER_THAN |
| // | MAT3x3 LESS_THAN type_decl GREATER_THAN |
| // | MAT3x4 LESS_THAN type_decl GREATER_THAN |
| // | MAT4x2 LESS_THAN type_decl GREATER_THAN |
| // | MAT4x3 LESS_THAN type_decl GREATER_THAN |
| // | MAT4x4 LESS_THAN type_decl GREATER_THAN |
| // | texture_samplers |
| Maybe<const ast::Type*> ParserImpl::type_decl() { |
| auto t = peek(); |
| Source source; |
| if (match(Token::Type::kIdentifier, &source)) { |
| return builder_.create<ast::TypeName>(source, builder_.Symbols().Register(t.to_str())); |
| } |
| |
| if (match(Token::Type::kBool, &source)) { |
| return builder_.ty.bool_(source); |
| } |
| |
| if (match(Token::Type::kF16, &source)) { |
| return builder_.ty.f16(source); |
| } |
| |
| if (match(Token::Type::kF32, &source)) { |
| return builder_.ty.f32(source); |
| } |
| |
| if (match(Token::Type::kI32, &source)) { |
| return builder_.ty.i32(source); |
| } |
| |
| if (match(Token::Type::kU32, &source)) { |
| return builder_.ty.u32(source); |
| } |
| |
| if (t.IsVector()) { |
| next(); // Consume the peek |
| return expect_type_decl_vector(t); |
| } |
| |
| if (match(Token::Type::kPtr)) { |
| return expect_type_decl_pointer(t); |
| } |
| |
| if (match(Token::Type::kAtomic)) { |
| return expect_type_decl_atomic(t); |
| } |
| |
| if (match(Token::Type::kArray, &source)) { |
| return expect_type_decl_array(t); |
| } |
| |
| if (t.IsMatrix()) { |
| next(); // Consume the peek |
| return expect_type_decl_matrix(t); |
| } |
| |
| auto texture_or_sampler = texture_samplers(); |
| if (texture_or_sampler.errored) { |
| return Failure::kErrored; |
| } |
| if (texture_or_sampler.matched) { |
| return texture_or_sampler; |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| Expect<const ast::Type*> ParserImpl::expect_type(std::string_view use) { |
| auto type = type_decl(); |
| if (type.errored) { |
| return Failure::kErrored; |
| } |
| if (!type.matched) { |
| return add_error(peek().source(), "invalid type", use); |
| } |
| return type.value; |
| } |
| |
| Expect<const ast::Type*> ParserImpl::expect_type_decl_pointer(Token t) { |
| const char* use = "ptr declaration"; |
| |
| auto storage_class = ast::StorageClass::kNone; |
| auto access = ast::Access::kUndefined; |
| |
| auto subtype = expect_lt_gt_block(use, [&]() -> Expect<const ast::Type*> { |
| auto sc = expect_storage_class(use); |
| if (sc.errored) { |
| return Failure::kErrored; |
| } |
| storage_class = sc.value; |
| |
| if (!expect(use, Token::Type::kComma)) { |
| return Failure::kErrored; |
| } |
| |
| auto type = expect_type(use); |
| if (type.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (match(Token::Type::kComma)) { |
| auto ac = expect_access("access control"); |
| if (ac.errored) { |
| return Failure::kErrored; |
| } |
| access = ac.value; |
| } |
| |
| return type.value; |
| }); |
| |
| if (subtype.errored) { |
| return Failure::kErrored; |
| } |
| |
| return builder_.ty.pointer(make_source_range_from(t.source()), subtype.value, storage_class, |
| access); |
| } |
| |
| Expect<const ast::Type*> ParserImpl::expect_type_decl_atomic(Token t) { |
| const char* use = "atomic declaration"; |
| |
| auto subtype = expect_lt_gt_block(use, [&] { return expect_type(use); }); |
| if (subtype.errored) { |
| return Failure::kErrored; |
| } |
| |
| return builder_.ty.atomic(make_source_range_from(t.source()), subtype.value); |
| } |
| |
| Expect<const ast::Type*> ParserImpl::expect_type_decl_vector(Token t) { |
| uint32_t count = 2; |
| if (t.Is(Token::Type::kVec3)) { |
| count = 3; |
| } else if (t.Is(Token::Type::kVec4)) { |
| count = 4; |
| } |
| |
| const ast::Type* subtype = nullptr; |
| if (peek_is(Token::Type::kLessThan)) { |
| const char* use = "vector"; |
| auto ty = expect_lt_gt_block(use, [&] { return expect_type(use); }); |
| if (ty.errored) { |
| return Failure::kErrored; |
| } |
| subtype = ty.value; |
| } |
| |
| return builder_.ty.vec(make_source_range_from(t.source()), subtype, count); |
| } |
| |
| Expect<const ast::Type*> ParserImpl::expect_type_decl_array(Token t) { |
| const char* use = "array declaration"; |
| |
| const ast::Expression* size = nullptr; |
| |
| auto subtype = expect_lt_gt_block(use, [&]() -> Expect<const ast::Type*> { |
| auto type = expect_type(use); |
| if (type.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (match(Token::Type::kComma)) { |
| auto expr = primary_expression(); |
| if (expr.errored) { |
| return Failure::kErrored; |
| } else if (!expr.matched) { |
| return add_error(peek(), "expected array size expression"); |
| } |
| |
| size = std::move(expr.value); |
| } |
| |
| return type.value; |
| }); |
| |
| if (subtype.errored) { |
| return Failure::kErrored; |
| } |
| |
| return builder_.ty.array(make_source_range_from(t.source()), subtype.value, size); |
| } |
| |
| Expect<const ast::Type*> ParserImpl::expect_type_decl_matrix(Token t) { |
| uint32_t rows = 2; |
| uint32_t columns = 2; |
| if (t.IsMat3xN()) { |
| columns = 3; |
| } else if (t.IsMat4xN()) { |
| columns = 4; |
| } |
| if (t.IsMatNx3()) { |
| rows = 3; |
| } else if (t.IsMatNx4()) { |
| rows = 4; |
| } |
| |
| const ast::Type* subtype = nullptr; |
| if (peek_is(Token::Type::kLessThan)) { |
| const char* use = "matrix"; |
| auto ty = expect_lt_gt_block(use, [&] { return expect_type(use); }); |
| if (ty.errored) { |
| return Failure::kErrored; |
| } |
| subtype = ty.value; |
| } |
| |
| return builder_.ty.mat(make_source_range_from(t.source()), subtype, columns, rows); |
| } |
| |
| // storage_class |
| // : INPUT |
| // | OUTPUT |
| // | UNIFORM |
| // | WORKGROUP |
| // | STORAGE |
| // | PRIVATE |
| // | FUNCTION |
| Expect<ast::StorageClass> ParserImpl::expect_storage_class(std::string_view use) { |
| auto source = peek().source(); |
| |
| if (match(Token::Type::kUniform)) { |
| return {ast::StorageClass::kUniform, source}; |
| } |
| |
| if (match(Token::Type::kWorkgroup)) { |
| return {ast::StorageClass::kWorkgroup, source}; |
| } |
| |
| if (match(Token::Type::kStorage)) { |
| return {ast::StorageClass::kStorage, source}; |
| } |
| |
| if (match(Token::Type::kPrivate)) { |
| return {ast::StorageClass::kPrivate, source}; |
| } |
| |
| if (match(Token::Type::kFunction)) { |
| return {ast::StorageClass::kFunction, source}; |
| } |
| |
| return add_error(source, "invalid storage class", use); |
| } |
| |
| // struct_decl |
| // : STRUCT IDENT struct_body_decl |
| Maybe<const ast::Struct*> ParserImpl::struct_decl() { |
| auto t = peek(); |
| auto source = t.source(); |
| |
| if (!match(Token::Type::kStruct)) { |
| return Failure::kNoMatch; |
| } |
| |
| auto name = expect_ident("struct declaration"); |
| if (name.errored) { |
| return Failure::kErrored; |
| } |
| |
| auto body = expect_struct_body_decl(); |
| if (body.errored) { |
| return Failure::kErrored; |
| } |
| |
| auto sym = builder_.Symbols().Register(name.value); |
| return create<ast::Struct>(source, sym, std::move(body.value), ast::AttributeList{}); |
| } |
| |
| // struct_body_decl |
| // : BRACE_LEFT (struct_member COMMA)* struct_member COMMA? BRACE_RIGHT |
| Expect<ast::StructMemberList> ParserImpl::expect_struct_body_decl() { |
| return expect_brace_block("struct declaration", [&]() -> Expect<ast::StructMemberList> { |
| ast::StructMemberList members; |
| bool errored = false; |
| while (continue_parsing()) { |
| // Check for the end of the list. |
| auto t = peek(); |
| if (!t.IsIdentifier() && !t.Is(Token::Type::kAttr)) { |
| break; |
| } |
| |
| auto member = expect_struct_member(); |
| if (member.errored) { |
| errored = true; |
| if (!sync_to(Token::Type::kComma, /* consume: */ false)) { |
| return Failure::kErrored; |
| } |
| } else { |
| members.push_back(member.value); |
| } |
| |
| // TODO(crbug.com/tint/1475): Remove support for semicolons. |
| if (auto sc = peek(); sc.Is(Token::Type::kSemicolon)) { |
| deprecated(sc.source(), "struct members should be separated with commas"); |
| next(); |
| continue; |
| } |
| if (!match(Token::Type::kComma)) { |
| break; |
| } |
| } |
| if (errored) { |
| return Failure::kErrored; |
| } |
| return members; |
| }); |
| } |
| |
| // struct_member |
| // : attribute* variable_ident_decl |
| Expect<ast::StructMember*> ParserImpl::expect_struct_member() { |
| auto attrs = attribute_list(); |
| if (attrs.errored) { |
| return Failure::kErrored; |
| } |
| |
| auto decl = expect_variable_ident_decl("struct member"); |
| if (decl.errored) { |
| return Failure::kErrored; |
| } |
| |
| return create<ast::StructMember>(decl->source, builder_.Symbols().Register(decl->name), |
| decl->type, std::move(attrs.value)); |
| } |
| |
| // function_decl |
| // : function_header body_stmt |
| Maybe<const ast::Function*> ParserImpl::function_decl(ast::AttributeList& attrs) { |
| auto header = function_header(); |
| if (header.errored) { |
| if (sync_to(Token::Type::kBraceLeft, /* consume: */ false)) { |
| // There were errors in the function header, but the parser has managed to |
| // resynchronize with the opening brace. As there's no outer |
| // synchronization token for function declarations, attempt to parse the |
| // function body. The AST isn't used as we've already errored, but this |
| // catches any errors inside the body, and can help keep the parser in |
| // sync. |
| expect_body_stmt(); |
| } |
| return Failure::kErrored; |
| } |
| if (!header.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| bool errored = false; |
| |
| auto body = expect_body_stmt(); |
| if (body.errored) { |
| errored = true; |
| } |
| |
| if (errored) { |
| return Failure::kErrored; |
| } |
| |
| return create<ast::Function>(header->source, builder_.Symbols().Register(header->name), |
| header->params, header->return_type, body.value, attrs, |
| header->return_type_attributes); |
| } |
| |
| // function_header |
| // : FN IDENT PAREN_LEFT param_list PAREN_RIGHT return_type_decl_optional |
| // return_type_decl_optional |
| // : |
| // | ARROW attribute_list* type_decl |
| Maybe<ParserImpl::FunctionHeader> ParserImpl::function_header() { |
| Source source; |
| if (!match(Token::Type::kFn, &source)) { |
| return Failure::kNoMatch; |
| } |
| |
| const char* use = "function declaration"; |
| bool errored = false; |
| |
| auto name = expect_ident(use); |
| if (name.errored) { |
| errored = true; |
| if (!sync_to(Token::Type::kParenLeft, /* consume: */ false)) { |
| return Failure::kErrored; |
| } |
| } |
| |
| auto params = expect_paren_block(use, [&] { return expect_param_list(); }); |
| if (params.errored) { |
| errored = true; |
| if (!synchronized_) { |
| return Failure::kErrored; |
| } |
| } |
| |
| const ast::Type* return_type = nullptr; |
| ast::AttributeList return_attributes; |
| |
| if (match(Token::Type::kArrow)) { |
| auto attrs = attribute_list(); |
| if (attrs.errored) { |
| return Failure::kErrored; |
| } |
| return_attributes = attrs.value; |
| |
| auto type = type_decl(); |
| if (type.errored) { |
| errored = true; |
| } else if (!type.matched) { |
| return add_error(peek(), "unable to determine function return type"); |
| } else { |
| return_type = type.value; |
| } |
| } else { |
| return_type = builder_.ty.void_(); |
| } |
| |
| if (errored) { |
| return Failure::kErrored; |
| } |
| |
| return FunctionHeader{source, name.value, std::move(params.value), return_type, |
| std::move(return_attributes)}; |
| } |
| |
| // param_list |
| // : |
| // | (param COMMA)* param COMMA? |
| Expect<ast::VariableList> ParserImpl::expect_param_list() { |
| ast::VariableList ret; |
| while (continue_parsing()) { |
| // Check for the end of the list. |
| auto t = peek(); |
| if (!t.IsIdentifier() && !t.Is(Token::Type::kAttr)) { |
| break; |
| } |
| |
| auto param = expect_param(); |
| if (param.errored) { |
| return Failure::kErrored; |
| } |
| ret.push_back(param.value); |
| |
| if (!match(Token::Type::kComma)) { |
| break; |
| } |
| } |
| |
| return ret; |
| } |
| |
| // param |
| // : attribute_list* variable_ident_decl |
| Expect<ast::Variable*> ParserImpl::expect_param() { |
| auto attrs = attribute_list(); |
| |
| auto decl = expect_variable_ident_decl("parameter"); |
| if (decl.errored) { |
| return Failure::kErrored; |
| } |
| |
| auto* var = create<ast::Variable>(decl->source, // source |
| builder_.Symbols().Register(decl->name), // symbol |
| ast::StorageClass::kNone, // storage class |
| ast::Access::kUndefined, // access control |
| decl->type, // type |
| true, // is_const |
| false, // is_overridable |
| nullptr, // constructor |
| std::move(attrs.value)); // attributes |
| // Formal parameters are treated like a const declaration where the |
| // initializer value is provided by the call's argument. The key point is |
| // that it's not updatable after initially set. This is unlike C or GLSL |
| // which treat formal parameters like local variables that can be updated. |
| |
| return var; |
| } |
| |
| // pipeline_stage |
| // : VERTEX |
| // | FRAGMENT |
| // | COMPUTE |
| Expect<ast::PipelineStage> ParserImpl::expect_pipeline_stage() { |
| auto t = peek(); |
| if (t == kVertexStage) { |
| next(); // Consume the peek |
| return {ast::PipelineStage::kVertex, t.source()}; |
| } |
| if (t == kFragmentStage) { |
| next(); // Consume the peek |
| return {ast::PipelineStage::kFragment, t.source()}; |
| } |
| if (t == kComputeStage) { |
| next(); // Consume the peek |
| return {ast::PipelineStage::kCompute, t.source()}; |
| } |
| return add_error(peek(), "invalid value for stage attribute"); |
| } |
| |
| Expect<ast::Builtin> ParserImpl::expect_builtin() { |
| auto ident = expect_ident("builtin"); |
| if (ident.errored) { |
| return Failure::kErrored; |
| } |
| |
| ast::Builtin builtin = ident_to_builtin(ident.value); |
| if (builtin == ast::Builtin::kNone) { |
| return add_error(ident.source, "invalid value for builtin attribute"); |
| } |
| |
| return {builtin, ident.source}; |
| } |
| |
| // body_stmt |
| // : BRACE_LEFT statements BRACE_RIGHT |
| Expect<ast::BlockStatement*> ParserImpl::expect_body_stmt() { |
| return expect_brace_block("", [&]() -> Expect<ast::BlockStatement*> { |
| auto stmts = expect_statements(); |
| if (stmts.errored) { |
| return Failure::kErrored; |
| } |
| return create<ast::BlockStatement>(Source{}, stmts.value); |
| }); |
| } |
| |
| // paren_rhs_stmt |
| // : PAREN_LEFT logical_or_expression PAREN_RIGHT |
| Expect<const ast::Expression*> ParserImpl::expect_paren_rhs_stmt() { |
| return expect_paren_block("", [&]() -> Expect<const ast::Expression*> { |
| auto expr = logical_or_expression(); |
| if (expr.errored) { |
| return Failure::kErrored; |
| } |
| if (!expr.matched) { |
| return add_error(peek(), "unable to parse expression"); |
| } |
| |
| return expr.value; |
| }); |
| } |
| |
| // statements |
| // : statement* |
| Expect<ast::StatementList> ParserImpl::expect_statements() { |
| bool errored = false; |
| ast::StatementList stmts; |
| |
| while (continue_parsing()) { |
| auto stmt = statement(); |
| if (stmt.errored) { |
| errored = true; |
| } else if (stmt.matched) { |
| stmts.emplace_back(stmt.value); |
| } else { |
| break; |
| } |
| } |
| |
| if (errored) { |
| return Failure::kErrored; |
| } |
| |
| return stmts; |
| } |
| |
| // statement |
| // : SEMICOLON |
| // | body_stmt? |
| // | if_stmt |
| // | switch_stmt |
| // | loop_stmt |
| // | for_stmt |
| // | non_block_statement |
| // : return_stmt SEMICOLON |
| // | func_call_stmt SEMICOLON |
| // | variable_stmt SEMICOLON |
| // | break_stmt SEMICOLON |
| // | continue_stmt SEMICOLON |
| // | DISCARD SEMICOLON |
| // | assignment_stmt SEMICOLON |
| // | increment_stmt SEMICOLON |
| // | decrement_stmt SEMICOLON |
| Maybe<const ast::Statement*> ParserImpl::statement() { |
| while (match(Token::Type::kSemicolon)) { |
| // Skip empty statements |
| } |
| |
| // Non-block statments that error can resynchronize on semicolon. |
| auto stmt = sync(Token::Type::kSemicolon, [&] { return non_block_statement(); }); |
| |
| if (stmt.errored) { |
| return Failure::kErrored; |
| } |
| if (stmt.matched) { |
| return stmt; |
| } |
| |
| auto stmt_if = if_stmt(); |
| if (stmt_if.errored) { |
| return Failure::kErrored; |
| } |
| if (stmt_if.matched) { |
| return stmt_if.value; |
| } |
| |
| auto sw = switch_stmt(); |
| if (sw.errored) { |
| return Failure::kErrored; |
| } |
| if (sw.matched) { |
| return sw.value; |
| } |
| |
| auto loop = loop_stmt(); |
| if (loop.errored) { |
| return Failure::kErrored; |
| } |
| if (loop.matched) { |
| return loop.value; |
| } |
| |
| auto stmt_for = for_stmt(); |
| if (stmt_for.errored) { |
| return Failure::kErrored; |
| } |
| if (stmt_for.matched) { |
| return stmt_for.value; |
| } |
| |
| if (peek_is(Token::Type::kBraceLeft)) { |
| auto body = expect_body_stmt(); |
| if (body.errored) { |
| return Failure::kErrored; |
| } |
| return body.value; |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| // statement (continued) |
| // : return_stmt SEMICOLON |
| // | func_call_stmt SEMICOLON |
| // | variable_stmt SEMICOLON |
| // | break_stmt SEMICOLON |
| // | continue_stmt SEMICOLON |
| // | DISCARD SEMICOLON |
| // | assignment_stmt SEMICOLON |
| // | increment_stmt SEMICOLON |
| // | decrement_stmt SEMICOLON |
| Maybe<const ast::Statement*> ParserImpl::non_block_statement() { |
| auto stmt = [&]() -> Maybe<const ast::Statement*> { |
| auto ret_stmt = return_stmt(); |
| if (ret_stmt.errored) { |
| return Failure::kErrored; |
| } |
| if (ret_stmt.matched) { |
| return ret_stmt.value; |
| } |
| |
| auto func = func_call_stmt(); |
| if (func.errored) { |
| return Failure::kErrored; |
| } |
| if (func.matched) { |
| return func.value; |
| } |
| |
| auto var = variable_stmt(); |
| if (var.errored) { |
| return Failure::kErrored; |
| } |
| if (var.matched) { |
| return var.value; |
| } |
| |
| auto b = break_stmt(); |
| if (b.errored) { |
| return Failure::kErrored; |
| } |
| if (b.matched) { |
| return b.value; |
| } |
| |
| auto cont = continue_stmt(); |
| if (cont.errored) { |
| return Failure::kErrored; |
| } |
| if (cont.matched) { |
| return cont.value; |
| } |
| |
| auto assign = assignment_stmt(); |
| if (assign.errored) { |
| return Failure::kErrored; |
| } |
| if (assign.matched) { |
| return assign.value; |
| } |
| |
| Source source; |
| if (match(Token::Type::kDiscard, &source)) { |
| return create<ast::DiscardStatement>(source); |
| } |
| |
| return Failure::kNoMatch; |
| }(); |
| |
| if (stmt.matched && !expect(stmt->Name(), Token::Type::kSemicolon)) { |
| return Failure::kErrored; |
| } |
| |
| return stmt; |
| } |
| |
| // return_stmt |
| // : RETURN logical_or_expression? |
| Maybe<const ast::ReturnStatement*> ParserImpl::return_stmt() { |
| Source source; |
| if (!match(Token::Type::kReturn, &source)) { |
| return Failure::kNoMatch; |
| } |
| |
| if (peek_is(Token::Type::kSemicolon)) { |
| return create<ast::ReturnStatement>(source, nullptr); |
| } |
| |
| auto expr = logical_or_expression(); |
| if (expr.errored) { |
| return Failure::kErrored; |
| } |
| |
| // TODO(bclayton): Check matched? |
| return create<ast::ReturnStatement>(source, expr.value); |
| } |
| |
| // variable_stmt |
| // : variable_decl |
| // | variable_decl EQUAL logical_or_expression |
| // | CONST variable_ident_decl EQUAL logical_or_expression |
| Maybe<const ast::VariableDeclStatement*> ParserImpl::variable_stmt() { |
| if (match(Token::Type::kLet)) { |
| auto decl = expect_variable_ident_decl("let declaration", |
| /*allow_inferred = */ true); |
| if (decl.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (!expect("let declaration", Token::Type::kEqual)) { |
| return Failure::kErrored; |
| } |
| |
| auto constructor = logical_or_expression(); |
| if (constructor.errored) { |
| return Failure::kErrored; |
| } |
| if (!constructor.matched) { |
| return add_error(peek(), "missing constructor for let declaration"); |
| } |
| |
| auto* var = create<ast::Variable>(decl->source, // source |
| builder_.Symbols().Register(decl->name), // symbol |
| ast::StorageClass::kNone, // storage class |
| ast::Access::kUndefined, // access control |
| decl->type, // type |
| true, // is_const |
| false, // is_overridable |
| constructor.value, // constructor |
| ast::AttributeList{}); // attributes |
| |
| return create<ast::VariableDeclStatement>(decl->source, var); |
| } |
| |
| auto decl = variable_decl(/*allow_inferred = */ true); |
| if (decl.errored) { |
| return Failure::kErrored; |
| } |
| if (!decl.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| const ast::Expression* constructor = nullptr; |
| if (match(Token::Type::kEqual)) { |
| auto constructor_expr = logical_or_expression(); |
| if (constructor_expr.errored) { |
| return Failure::kErrored; |
| } |
| if (!constructor_expr.matched) { |
| return add_error(peek(), "missing constructor for variable declaration"); |
| } |
| |
| constructor = constructor_expr.value; |
| } |
| |
| auto* var = create<ast::Variable>(decl->source, // source |
| builder_.Symbols().Register(decl->name), // symbol |
| decl->storage_class, // storage class |
| decl->access, // access control |
| decl->type, // type |
| false, // is_const |
| false, // is_overridable |
| constructor, // constructor |
| ast::AttributeList{}); // attributes |
| |
| return create<ast::VariableDeclStatement>(var->source, var); |
| } |
| |
| // if_stmt |
| // : IF expression compound_stmt ( ELSE else_stmt ) ? |
| // else_stmt |
| // : body_stmt |
| // | if_stmt |
| Maybe<const ast::IfStatement*> ParserImpl::if_stmt() { |
| // Parse if-else chains iteratively instead of recursively, to avoid |
| // stack-overflow for long chains of if-else statements. |
| |
| struct IfInfo { |
| Source source; |
| const ast::Expression* condition; |
| const ast::BlockStatement* body; |
| }; |
| |
| // Parse an if statement, capturing the source, condition, and body statement. |
| auto parse_if = [&]() -> Maybe<IfInfo> { |
| Source source; |
| if (!match(Token::Type::kIf, &source)) { |
| return Failure::kNoMatch; |
| } |
| |
| auto condition = logical_or_expression(); |
| if (condition.errored) { |
| return Failure::kErrored; |
| } |
| if (!condition.matched) { |
| return add_error(peek(), "unable to parse condition expression"); |
| } |
| |
| auto body = expect_body_stmt(); |
| if (body.errored) { |
| return Failure::kErrored; |
| } |
| |
| return IfInfo{source, condition.value, body.value}; |
| }; |
| |
| std::vector<IfInfo> statements; |
| |
| // Parse the first if statement. |
| auto first_if = parse_if(); |
| if (first_if.errored) { |
| return Failure::kErrored; |
| } else if (!first_if.matched) { |
| return Failure::kNoMatch; |
| } |
| statements.push_back(first_if.value); |
| |
| // Parse the components of every "else {if}" in the chain. |
| const ast::Statement* last_stmt = nullptr; |
| while (continue_parsing()) { |
| if (!match(Token::Type::kElse)) { |
| break; |
| } |
| |
| // Try to parse an "else if". |
| auto else_if = parse_if(); |
| if (else_if.errored) { |
| return Failure::kErrored; |
| } else if (else_if.matched) { |
| statements.push_back(else_if.value); |
| continue; |
| } |
| |
| // If it wasn't an "else if", it must just be an "else". |
| auto else_body = expect_body_stmt(); |
| if (else_body.errored) { |
| return Failure::kErrored; |
| } |
| last_stmt = else_body.value; |
| break; |
| } |
| |
| // Now walk back through the statements to create their AST nodes. |
| for (auto itr = statements.rbegin(); itr != statements.rend(); itr++) { |
| last_stmt = create<ast::IfStatement>(itr->source, itr->condition, itr->body, last_stmt); |
| } |
| |
| return last_stmt->As<ast::IfStatement>(); |
| } |
| |
| // switch_stmt |
| // : SWITCH paren_rhs_stmt BRACKET_LEFT switch_body+ BRACKET_RIGHT |
| Maybe<const ast::SwitchStatement*> ParserImpl::switch_stmt() { |
| Source source; |
| if (!match(Token::Type::kSwitch, &source)) { |
| return Failure::kNoMatch; |
| } |
| |
| auto condition = logical_or_expression(); |
| if (condition.errored) { |
| return Failure::kErrored; |
| } |
| if (!condition.matched) { |
| return add_error(peek(), "unable to parse selector expression"); |
| } |
| |
| auto body = expect_brace_block("switch statement", [&]() -> Expect<ast::CaseStatementList> { |
| bool errored = false; |
| ast::CaseStatementList list; |
| while (continue_parsing()) { |
| auto stmt = switch_body(); |
| if (stmt.errored) { |
| errored = true; |
| continue; |
| } |
| if (!stmt.matched) { |
| break; |
| } |
| list.push_back(stmt.value); |
| } |
| if (errored) { |
| return Failure::kErrored; |
| } |
| return list; |
| }); |
| |
| if (body.errored) { |
| return Failure::kErrored; |
| } |
| |
| return create<ast::SwitchStatement>(source, condition.value, body.value); |
| } |
| |
| // switch_body |
| // : CASE case_selectors COLON? BRACKET_LEFT case_body BRACKET_RIGHT |
| // | DEFAULT COLON? BRACKET_LEFT case_body BRACKET_RIGHT |
| Maybe<const ast::CaseStatement*> ParserImpl::switch_body() { |
| if (!peek_is(Token::Type::kCase) && !peek_is(Token::Type::kDefault)) { |
| return Failure::kNoMatch; |
| } |
| |
| auto t = next(); |
| auto source = t.source(); |
| |
| ast::CaseSelectorList selector_list; |
| if (t.Is(Token::Type::kCase)) { |
| auto selectors = expect_case_selectors(); |
| if (selectors.errored) { |
| return Failure::kErrored; |
| } |
| |
| selector_list = std::move(selectors.value); |
| } |
| |
| // Consume the optional colon if present. |
| match(Token::Type::kColon); |
| |
| const char* use = "case statement"; |
| auto body = expect_brace_block(use, [&] { return case_body(); }); |
| |
| if (body.errored) { |
| return Failure::kErrored; |
| } |
| if (!body.matched) { |
| return add_error(body.source, "expected case body"); |
| } |
| |
| return create<ast::CaseStatement>(source, selector_list, body.value); |
| } |
| |
| // case_selectors |
| // : const_literal (COMMA const_literal)* COMMA? |
| Expect<ast::CaseSelectorList> ParserImpl::expect_case_selectors() { |
| ast::CaseSelectorList selectors; |
| |
| while (continue_parsing()) { |
| auto cond = const_literal(); |
| if (cond.errored) { |
| return Failure::kErrored; |
| } else if (!cond.matched) { |
| break; |
| } else if (!cond->Is<ast::IntLiteralExpression>()) { |
| return add_error(cond.value->source, "invalid case selector must be an integer value"); |
| } |
| |
| selectors.push_back(cond.value->As<ast::IntLiteralExpression>()); |
| |
| if (!match(Token::Type::kComma)) { |
| break; |
| } |
| } |
| |
| if (selectors.empty()) { |
| return add_error(peek(), "unable to parse case selectors"); |
| } |
| |
| return selectors; |
| } |
| |
| // case_body |
| // : |
| // | statement case_body |
| // | FALLTHROUGH SEMICOLON |
| Maybe<const ast::BlockStatement*> ParserImpl::case_body() { |
| ast::StatementList stmts; |
| while (continue_parsing()) { |
| Source source; |
| if (match(Token::Type::kFallthrough, &source)) { |
| if (!expect("fallthrough statement", Token::Type::kSemicolon)) { |
| return Failure::kErrored; |
| } |
| |
| stmts.emplace_back(create<ast::FallthroughStatement>(source)); |
| break; |
| } |
| |
| auto stmt = statement(); |
| if (stmt.errored) { |
| return Failure::kErrored; |
| } |
| if (!stmt.matched) { |
| break; |
| } |
| |
| stmts.emplace_back(stmt.value); |
| } |
| |
| return create<ast::BlockStatement>(Source{}, stmts); |
| } |
| |
| // loop_stmt |
| // : LOOP BRACKET_LEFT statements continuing_stmt? BRACKET_RIGHT |
| Maybe<const ast::LoopStatement*> ParserImpl::loop_stmt() { |
| Source source; |
| if (!match(Token::Type::kLoop, &source)) { |
| return Failure::kNoMatch; |
| } |
| |
| return expect_brace_block("loop", [&]() -> Maybe<const ast::LoopStatement*> { |
| auto stmts = expect_statements(); |
| if (stmts.errored) { |
| return Failure::kErrored; |
| } |
| |
| auto continuing = continuing_stmt(); |
| if (continuing.errored) { |
| return Failure::kErrored; |
| } |
| |
| auto* body = create<ast::BlockStatement>(source, stmts.value); |
| return create<ast::LoopStatement>(source, body, continuing.value); |
| }); |
| } |
| |
| ForHeader::ForHeader(const ast::Statement* init, |
| const ast::Expression* cond, |
| const ast::Statement* cont) |
| : initializer(init), condition(cond), continuing(cont) {} |
| |
| ForHeader::~ForHeader() = default; |
| |
| // (variable_stmt | increment_stmt | decrement_stmt | assignment_stmt | |
| // func_call_stmt)? |
| Maybe<const ast::Statement*> ParserImpl::for_header_initializer() { |
| auto call = func_call_stmt(); |
| if (call.errored) { |
| return Failure::kErrored; |
| } |
| if (call.matched) { |
| return call.value; |
| } |
| |
| auto var = variable_stmt(); |
| if (var.errored) { |
| return Failure::kErrored; |
| } |
| if (var.matched) { |
| return var.value; |
| } |
| |
| auto assign = assignment_stmt(); |
| if (assign.errored) { |
| return Failure::kErrored; |
| } |
| if (assign.matched) { |
| return assign.value; |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| // (increment_stmt | decrement_stmt | assignment_stmt | func_call_stmt)? |
| Maybe<const ast::Statement*> ParserImpl::for_header_continuing() { |
| auto call_stmt = func_call_stmt(); |
| if (call_stmt.errored) { |
| return Failure::kErrored; |
| } |
| if (call_stmt.matched) { |
| return call_stmt.value; |
| } |
| |
| auto assign = assignment_stmt(); |
| if (assign.errored) { |
| return Failure::kErrored; |
| } |
| if (assign.matched) { |
| return assign.value; |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| // for_header |
| // : (variable_stmt | assignment_stmt | func_call_stmt)? |
| // SEMICOLON |
| // logical_or_expression? SEMICOLON |
| // (assignment_stmt | func_call_stmt)? |
| Expect<std::unique_ptr<ForHeader>> ParserImpl::expect_for_header() { |
| auto initializer = for_header_initializer(); |
| if (initializer.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (!expect("initializer in for loop", Token::Type::kSemicolon)) { |
| return Failure::kErrored; |
| } |
| |
| auto condition = logical_or_expression(); |
| if (condition.errored) { |
| return Failure::kErrored; |
| } |
| |
| if (!expect("condition in for loop", Token::Type::kSemicolon)) { |
| return Failure::kErrored; |
| } |
| |
| auto continuing = for_header_continuing(); |
| if (continuing.errored) { |
| return Failure::kErrored; |
| } |
| |
| return std::make_unique<ForHeader>(initializer.value, condition.value, continuing.value); |
| } |
| |
| // for_statement |
| // : FOR PAREN_LEFT for_header PAREN_RIGHT BRACE_LEFT statements BRACE_RIGHT |
| Maybe<const ast::ForLoopStatement*> ParserImpl::for_stmt() { |
| Source source; |
| if (!match(Token::Type::kFor, &source)) { |
| return Failure::kNoMatch; |
| } |
| |
| auto header = expect_paren_block("for loop", [&] { return expect_for_header(); }); |
| if (header.errored) { |
| return Failure::kErrored; |
| } |
| |
| auto stmts = expect_brace_block("for loop", [&] { return expect_statements(); }); |
| if (stmts.errored) { |
| return Failure::kErrored; |
| } |
| |
| return create<ast::ForLoopStatement>(source, header->initializer, header->condition, |
| header->continuing, |
| create<ast::BlockStatement>(stmts.value)); |
| } |
| |
| // func_call_stmt |
| // : IDENT argument_expression_list |
| Maybe<const ast::CallStatement*> ParserImpl::func_call_stmt() { |
| auto t = peek(); |
| auto t2 = peek(1); |
| if (!t.IsIdentifier() || !t2.Is(Token::Type::kParenLeft)) { |
| return Failure::kNoMatch; |
| } |
| |
| next(); // Consume the first peek |
| |
| auto source = t.source(); |
| auto name = t.to_str(); |
| |
| auto params = expect_argument_expression_list("function call"); |
| if (params.errored) { |
| return Failure::kErrored; |
| } |
| |
| return create<ast::CallStatement>( |
| source, |
| create<ast::CallExpression>( |
| source, create<ast::IdentifierExpression>(source, builder_.Symbols().Register(name)), |
| std::move(params.value))); |
| } |
| |
| // break_stmt |
| // : BREAK |
| Maybe<const ast::BreakStatement*> ParserImpl::break_stmt() { |
| Source source; |
| if (!match(Token::Type::kBreak, &source)) { |
| return Failure::kNoMatch; |
| } |
| |
| return create<ast::BreakStatement>(source); |
| } |
| |
| // continue_stmt |
| // : CONTINUE |
| Maybe<const ast::ContinueStatement*> ParserImpl::continue_stmt() { |
| Source source; |
| if (!match(Token::Type::kContinue, &source)) { |
| return Failure::kNoMatch; |
| } |
| |
| return create<ast::ContinueStatement>(source); |
| } |
| |
| // continuing_stmt |
| // : CONTINUING body_stmt |
| Maybe<const ast::BlockStatement*> ParserImpl::continuing_stmt() { |
| if (!match(Token::Type::kContinuing)) { |
| return create<ast::BlockStatement>(Source{}, ast::StatementList{}); |
| } |
| |
| return expect_body_stmt(); |
| } |
| |
| // primary_expression |
| // : IDENT argument_expression_list? |
| // | type_decl argument_expression_list |
| // | const_literal |
| // | paren_rhs_stmt |
| // | BITCAST LESS_THAN type_decl GREATER_THAN paren_rhs_stmt |
| Maybe<const ast::Expression*> ParserImpl::primary_expression() { |
| auto t = peek(); |
| auto source = t.source(); |
| |
| auto lit = const_literal(); |
| if (lit.errored) { |
| return Failure::kErrored; |
| } |
| if (lit.matched) { |
| return lit.value; |
| } |
| |
| if (t.Is(Token::Type::kParenLeft)) { |
| auto paren = expect_paren_rhs_stmt(); |
| if (paren.errored) { |
| return Failure::kErrored; |
| } |
| |
| return paren.value; |
| } |
| |
| if (match(Token::Type::kBitcast)) { |
| const char* use = "bitcast expression"; |
| |
| auto type = expect_lt_gt_block(use, [&] { return expect_type(use); }); |
| if (type.errored) { |
| return Failure::kErrored; |
| } |
| |
| auto params = expect_paren_rhs_stmt(); |
| if (params.errored) { |
| return Failure::kErrored; |
| } |
| |
| return create<ast::BitcastExpression>(source, type.value, params.value); |
| } |
| |
| if (t.IsIdentifier()) { |
| next(); |
| |
| auto* ident = |
| create<ast::IdentifierExpression>(t.source(), builder_.Symbols().Register(t.to_str())); |
| |
| if (peek_is(Token::Type::kParenLeft)) { |
| auto params = expect_argument_expression_list("function call"); |
| if (params.errored) { |
| return Failure::kErrored; |
| } |
| |
| return create<ast::CallExpression>(source, ident, std::move(params.value)); |
| } |
| |
| return ident; |
| } |
| |
| auto type = type_decl(); |
| if (type.errored) { |
| return Failure::kErrored; |
| } |
| if (type.matched) { |
| auto params = expect_argument_expression_list("type constructor"); |
| if (params.errored) { |
| return Failure::kErrored; |
| } |
| |
| return builder_.Construct(source, type.value, std::move(params.value)); |
| } |
| |
| return Failure::kNoMatch; |
| } |
| |
| // postfix_expression |
| // : |
| // | BRACE_LEFT logical_or_expression BRACE_RIGHT postfix_expr |
| // | PERIOD IDENTIFIER postfix_expr |
| Maybe<const ast::Expression*> ParserImpl::postfix_expression(const ast::Expression* prefix) { |
| Source source; |
| |
| while (continue_parsing()) { |
| if (match(Token::Type::kBracketLeft, &source)) { |
| auto res = sync(Token::Type::kBracketRight, [&]() -> Maybe<const ast::Expression*> { |
| auto param = logical_or_expression(); |
| if (param.errored) { |
| return Failure::kErrored; |
| } |
| if (!param.matched) { |
| return add_error(peek(), "unable to parse expression inside []"); |
| } |
| |
| if (!expect("index accessor", Token::Type::kBracketRight)) { |
| return Failure::kErrored; |
| } |
| |
| return create<ast::IndexAccessorExpression>(source, prefix, param.value); |
| }); |
| |
| if (res.errored) { |
| return res; |
| } |
| prefix = res.value; |
| continue; |
| } |
| |
| if (match(Token::Type::kPeriod)) { |
| auto ident = expect_ident("member accessor"); |
| if (ident.errored) { |
| return Failure::kErrored; |
| } |
| |
| prefix = create<ast::MemberAccessorExpression>( |
| ident.source, prefix, |
| create<ast::IdentifierExpression>(ident.source, |
| builder_.Symbols().Register(ident.value))); |
| continue; |
| } |
| |
| return prefix; |
| } |
| |
| return Failure::kErrored; |
| } |
| |
| // singular_expression |
| // : primary_expression postfix_expr |
| Maybe<const ast::Expression*> ParserImpl::singular_expression() { |
| auto prefix = primary_expression(); |
| if (prefix.errored) { |
| return Failure::kErrored; |
| } |
| if (!prefix.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| return postfix_expression(prefix.value); |
| } |
| |
| // argument_expression_list |
| // : PAREN_LEFT ((logical_or_expression COMMA)* logical_or_expression COMMA?)? |
| // PAREN_RIGHT |
| Expect<ast::ExpressionList> ParserImpl::expect_argument_expression_list(std::string_view use) { |
| return expect_paren_block(use, [&]() -> Expect<ast::ExpressionList> { |
| ast::ExpressionList ret; |
| while (continue_parsing()) { |
| auto arg = logical_or_expression(); |
| if (arg.errored) { |
| return Failure::kErrored; |
| } else if (!arg.matched) { |
| break; |
| } |
| ret.push_back(arg.value); |
| |
| if (!match(Token::Type::kComma)) { |
| break; |
| } |
| } |
| return ret; |
| }); |
| } |
| |
| // unary_expression |
| // : singular_expression |
| // | MINUS unary_expression |
| // | BANG unary_expression |
| // | TILDE unary_expression |
| // | STAR unary_expression |
| // | AND unary_expression |
| Maybe<const ast::Expression*> ParserImpl::unary_expression() { |
| auto t = peek(); |
| |
| if (match(Token::Type::kPlusPlus) || match(Token::Type::kMinusMinus)) { |
| add_error(t.source(), |
| "prefix increment and decrement operators are reserved for a " |
| "future WGSL version"); |
| return Failure::kErrored; |
| } |
| |
| ast::UnaryOp op; |
| if (match(Token::Type::kMinus)) { |
| op = ast::UnaryOp::kNegation; |
| } else if (match(Token::Type::kBang)) { |
| op = ast::UnaryOp::kNot; |
| } else if (match(Token::Type::kTilde)) { |
| op = ast::UnaryOp::kComplement; |
| } else if (match(Token::Type::kStar)) { |
| op = ast::UnaryOp::kIndirection; |
| } else if (match(Token::Type::kAnd)) { |
| op = ast::UnaryOp::kAddressOf; |
| } else { |
| return singular_expression(); |
| } |
| |
| if (parse_depth_ >= kMaxParseDepth) { |
| // We've hit a maximum parser recursive depth. |
| // We can't call into unary_expression() as we might stack overflow. |
| // Instead, report an error |
| add_error(peek(), "maximum parser recursive depth reached"); |
| return Failure::kErrored; |
| } |
| |
| ++parse_depth_; |
| auto expr = unary_expression(); |
| --parse_depth_; |
| |
| if (expr.errored) { |
| return Failure::kErrored; |
| } |
| if (!expr.matched) { |
| return add_error( |
| peek(), "unable to parse right side of " + std::string(t.to_name()) + " expression"); |
| } |
| |
| return create<ast::UnaryOpExpression>(t.source(), op, expr.value); |
| } |
| |
| // multiplicative_expr |
| // : |
| // | STAR unary_expression multiplicative_expr |
| // | FORWARD_SLASH unary_expression multiplicative_expr |
| // | MODULO unary_expression multiplicative_expr |
| Expect<const ast::Expression*> ParserImpl::expect_multiplicative_expr(const ast::Expression* lhs) { |
| while (continue_parsing()) { |
| ast::BinaryOp op = ast::BinaryOp::kNone; |
| if (peek_is(Token::Type::kStar)) { |
| op = ast::BinaryOp::kMultiply; |
| } else if (peek_is(Token::Type::kForwardSlash)) { |
| op = ast::BinaryOp::kDivide; |
| } else if (peek_is(Token::Type::kMod)) { |
| op = ast::BinaryOp::kModulo; |
| } else { |
| return lhs; |
| } |
| |
| auto t = next(); |
| auto source = t.source(); |
| auto name = t.to_name(); |
| |
| auto rhs = unary_expression(); |
| if (rhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!rhs.matched) { |
| return add_error(peek(), |
| "unable to parse right side of " + std::string(name) + " expression"); |
| } |
| |
| lhs = create<ast::BinaryExpression>(source, op, lhs, rhs.value); |
| } |
| return Failure::kErrored; |
| } |
| |
| // multiplicative_expression |
| // : unary_expression multiplicative_expr |
| Maybe<const ast::Expression*> ParserImpl::multiplicative_expression() { |
| auto lhs = unary_expression(); |
| if (lhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!lhs.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| return expect_multiplicative_expr(lhs.value); |
| } |
| |
| // additive_expr |
| // : |
| // | PLUS multiplicative_expression additive_expr |
| // | MINUS multiplicative_expression additive_expr |
| Expect<const ast::Expression*> ParserImpl::expect_additive_expr(const ast::Expression* lhs) { |
| while (continue_parsing()) { |
| ast::BinaryOp op = ast::BinaryOp::kNone; |
| if (peek_is(Token::Type::kPlus)) { |
| op = ast::BinaryOp::kAdd; |
| } else if (peek_is(Token::Type::kMinus)) { |
| op = ast::BinaryOp::kSubtract; |
| } else { |
| return lhs; |
| } |
| |
| auto t = next(); |
| auto source = t.source(); |
| |
| auto rhs = multiplicative_expression(); |
| if (rhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!rhs.matched) { |
| return add_error(peek(), "unable to parse right side of + expression"); |
| } |
| |
| lhs = create<ast::BinaryExpression>(source, op, lhs, rhs.value); |
| } |
| return Failure::kErrored; |
| } |
| |
| // additive_expression |
| // : multiplicative_expression additive_expr |
| Maybe<const ast::Expression*> ParserImpl::additive_expression() { |
| auto lhs = multiplicative_expression(); |
| if (lhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!lhs.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| return expect_additive_expr(lhs.value); |
| } |
| |
| // shift_expr |
| // : |
| // | SHIFT_LEFT additive_expression shift_expr |
| // | SHIFT_RIGHT additive_expression shift_expr |
| Expect<const ast::Expression*> ParserImpl::expect_shift_expr(const ast::Expression* lhs) { |
| while (continue_parsing()) { |
| auto* name = ""; |
| ast::BinaryOp op = ast::BinaryOp::kNone; |
| if (peek_is(Token::Type::kShiftLeft)) { |
| op = ast::BinaryOp::kShiftLeft; |
| name = "<<"; |
| } else if (peek_is(Token::Type::kShiftRight)) { |
| op = ast::BinaryOp::kShiftRight; |
| name = ">>"; |
| } else { |
| return lhs; |
| } |
| |
| auto t = next(); |
| auto source = t.source(); |
| auto rhs = additive_expression(); |
| if (rhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!rhs.matched) { |
| return add_error(peek(), |
| std::string("unable to parse right side of ") + name + " expression"); |
| } |
| |
| return lhs = create<ast::BinaryExpression>(source, op, lhs, rhs.value); |
| } |
| return Failure::kErrored; |
| } |
| |
| // shift_expression |
| // : additive_expression shift_expr |
| Maybe<const ast::Expression*> ParserImpl::shift_expression() { |
| auto lhs = additive_expression(); |
| if (lhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!lhs.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| return expect_shift_expr(lhs.value); |
| } |
| |
| // relational_expr |
| // : |
| // | LESS_THAN shift_expression relational_expr |
| // | GREATER_THAN shift_expression relational_expr |
| // | LESS_THAN_EQUAL shift_expression relational_expr |
| // | GREATER_THAN_EQUAL shift_expression relational_expr |
| Expect<const ast::Expression*> ParserImpl::expect_relational_expr(const ast::Expression* lhs) { |
| while (continue_parsing()) { |
| ast::BinaryOp op = ast::BinaryOp::kNone; |
| if (peek_is(Token::Type::kLessThan)) { |
| op = ast::BinaryOp::kLessThan; |
| } else if (peek_is(Token::Type::kGreaterThan)) { |
| op = ast::BinaryOp::kGreaterThan; |
| } else if (peek_is(Token::Type::kLessThanEqual)) { |
| op = ast::BinaryOp::kLessThanEqual; |
| } else if (peek_is(Token::Type::kGreaterThanEqual)) { |
| op = ast::BinaryOp::kGreaterThanEqual; |
| } else { |
| return lhs; |
| } |
| |
| auto t = next(); |
| auto source = t.source(); |
| auto name = t.to_name(); |
| |
| auto rhs = shift_expression(); |
| if (rhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!rhs.matched) { |
| return add_error(peek(), |
| "unable to parse right side of " + std::string(name) + " expression"); |
| } |
| |
| lhs = create<ast::BinaryExpression>(source, op, lhs, rhs.value); |
| } |
| return Failure::kErrored; |
| } |
| |
| // relational_expression |
| // : shift_expression relational_expr |
| Maybe<const ast::Expression*> ParserImpl::relational_expression() { |
| auto lhs = shift_expression(); |
| if (lhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!lhs.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| return expect_relational_expr(lhs.value); |
| } |
| |
| // equality_expr |
| // : |
| // | EQUAL_EQUAL relational_expression equality_expr |
| // | NOT_EQUAL relational_expression equality_expr |
| Expect<const ast::Expression*> ParserImpl::expect_equality_expr(const ast::Expression* lhs) { |
| while (continue_parsing()) { |
| ast::BinaryOp op = ast::BinaryOp::kNone; |
| if (peek_is(Token::Type::kEqualEqual)) { |
| op = ast::BinaryOp::kEqual; |
| } else if (peek_is(Token::Type::kNotEqual)) { |
| op = ast::BinaryOp::kNotEqual; |
| } else { |
| return lhs; |
| } |
| |
| auto t = next(); |
| auto source = t.source(); |
| auto name = t.to_name(); |
| |
| auto rhs = relational_expression(); |
| if (rhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!rhs.matched) { |
| return add_error(peek(), |
| "unable to parse right side of " + std::string(name) + " expression"); |
| } |
| |
| lhs = create<ast::BinaryExpression>(source, op, lhs, rhs.value); |
| } |
| return Failure::kErrored; |
| } |
| |
| // equality_expression |
| // : relational_expression equality_expr |
| Maybe<const ast::Expression*> ParserImpl::equality_expression() { |
| auto lhs = relational_expression(); |
| if (lhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!lhs.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| return expect_equality_expr(lhs.value); |
| } |
| |
| // and_expr |
| // : |
| // | AND equality_expression and_expr |
| Expect<const ast::Expression*> ParserImpl::expect_and_expr(const ast::Expression* lhs) { |
| while (continue_parsing()) { |
| if (!peek_is(Token::Type::kAnd)) { |
| return lhs; |
| } |
| |
| auto t = next(); |
| auto source = t.source(); |
| |
| auto rhs = equality_expression(); |
| if (rhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!rhs.matched) { |
| return add_error(peek(), "unable to parse right side of & expression"); |
| } |
| |
| lhs = create<ast::BinaryExpression>(source, ast::BinaryOp::kAnd, lhs, rhs.value); |
| } |
| return Failure::kErrored; |
| } |
| |
| // and_expression |
| // : equality_expression and_expr |
| Maybe<const ast::Expression*> ParserImpl::and_expression() { |
| auto lhs = equality_expression(); |
| if (lhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!lhs.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| return expect_and_expr(lhs.value); |
| } |
| |
| // exclusive_or_expr |
| // : |
| // | XOR and_expression exclusive_or_expr |
| Expect<const ast::Expression*> ParserImpl::expect_exclusive_or_expr(const ast::Expression* lhs) { |
| while (continue_parsing()) { |
| Source source; |
| if (!match(Token::Type::kXor, &source)) { |
| return lhs; |
| } |
| |
| auto rhs = and_expression(); |
| if (rhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!rhs.matched) { |
| return add_error(peek(), "unable to parse right side of ^ expression"); |
| } |
| |
| lhs = create<ast::BinaryExpression>(source, ast::BinaryOp::kXor, lhs, rhs.value); |
| } |
| return Failure::kErrored; |
| } |
| |
| // exclusive_or_expression |
| // : and_expression exclusive_or_expr |
| Maybe<const ast::Expression*> ParserImpl::exclusive_or_expression() { |
| auto lhs = and_expression(); |
| if (lhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!lhs.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| return expect_exclusive_or_expr(lhs.value); |
| } |
| |
| // inclusive_or_expr |
| // : |
| // | OR exclusive_or_expression inclusive_or_expr |
| Expect<const ast::Expression*> ParserImpl::expect_inclusive_or_expr(const ast::Expression* lhs) { |
| while (continue_parsing()) { |
| Source source; |
| if (!match(Token::Type::kOr, &source)) { |
| return lhs; |
| } |
| |
| auto rhs = exclusive_or_expression(); |
| if (rhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!rhs.matched) { |
| return add_error(peek(), "unable to parse right side of | expression"); |
| } |
| |
| lhs = create<ast::BinaryExpression>(source, ast::BinaryOp::kOr, lhs, rhs.value); |
| } |
| return Failure::kErrored; |
| } |
| |
| // inclusive_or_expression |
| // : exclusive_or_expression inclusive_or_expr |
| Maybe<const ast::Expression*> ParserImpl::inclusive_or_expression() { |
| auto lhs = exclusive_or_expression(); |
| if (lhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!lhs.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| return expect_inclusive_or_expr(lhs.value); |
| } |
| |
| // logical_and_expr |
| // : |
| // | AND_AND inclusive_or_expression logical_and_expr |
| Expect<const ast::Expression*> ParserImpl::expect_logical_and_expr(const ast::Expression* lhs) { |
| while (continue_parsing()) { |
| if (!peek_is(Token::Type::kAndAnd)) { |
| return lhs; |
| } |
| |
| auto t = next(); |
| auto source = t.source(); |
| |
| auto rhs = inclusive_or_expression(); |
| if (rhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!rhs.matched) { |
| return add_error(peek(), "unable to parse right side of && expression"); |
| } |
| |
| lhs = create<ast::BinaryExpression>(source, ast::BinaryOp::kLogicalAnd, lhs, rhs.value); |
| } |
| return Failure::kErrored; |
| } |
| |
| // logical_and_expression |
| // : inclusive_or_expression logical_and_expr |
| Maybe<const ast::Expression*> ParserImpl::logical_and_expression() { |
| auto lhs = inclusive_or_expression(); |
| if (lhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!lhs.matched) { |
| return Failure::kNoMatch; |
| } |
| |
| return expect_logical_and_expr(lhs.value); |
| } |
| |
| // logical_or_expr |
| // : |
| // | OR_OR logical_and_expression logical_or_expr |
| Expect<const ast::Expression*> ParserImpl::expect_logical_or_expr(const ast::Expression* lhs) { |
| while (continue_parsing()) { |
| Source source; |
| if (!match(Token::Type::kOrOr, &source)) { |
| return lhs; |
| } |
| |
| auto rhs = logical_and_expression(); |
| if (rhs.errored) { |
| return Failure::kErrored; |
| } |
| if (!rhs.matched) { |
| return add_error(peek(), "unable to parse right side of || expression"); |
| } |
| |
| lhs = create<ast::BinaryExpression>(source, ast::BinaryOp::kLogicalOr, lhs, rhs.value); |
| } |
| return Failure::kErrored; |
| } |
| |
| // logical_or_expression |
| // : logical_and_expression logical_or_expr |
| Maybe<const ast::Expression*> ParserImpl::logical_or_expression() { |
| auto lhs = logical_and_expression(); |
| if (lhs.errored) { |
| return Failure::kErrored; |
| } |
| if (! |