wsgl parser: Use match() for trivial patterns
Replace uses of peek, test, return-or-next with match().
Reduces code.
Bug: tint:282
Change-Id: I5e53601746e78efd007773cfea7109483c5e1630
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/31726
Commit-Queue: dan sinclair <dsinclair@chromium.org>
Reviewed-by: dan sinclair <dsinclair@chromium.org>
diff --git a/src/reader/wgsl/parser_impl.cc b/src/reader/wgsl/parser_impl.cc
index 84af7b5..9634793 100644
--- a/src/reader/wgsl/parser_impl.cc
+++ b/src/reader/wgsl/parser_impl.cc
@@ -315,10 +315,7 @@
var = std::move(dv);
}
- auto t = peek();
- if (t.IsEqual()) {
- next(); // Consume the peek
-
+ if (match(Token::Type::kEqual)) {
auto expr = const_expr();
if (has_error())
return nullptr;
@@ -335,12 +332,9 @@
// global_constant_decl
// : CONST variable_ident_decl EQUAL const_expr
std::unique_ptr<ast::Variable> ParserImpl::global_constant_decl() {
- auto t = peek();
- if (!t.IsConst())
+ if (!match(Token::Type::kConst))
return nullptr;
- next(); // Consume the peek
-
auto decl = variable_ident_decl();
if (has_error())
return nullptr;
@@ -353,7 +347,7 @@
decl.source, decl.name, ast::StorageClass::kNone, decl.type);
var->set_is_const(true);
- t = next();
+ auto t = next();
if (!t.IsEqual()) {
add_error(t, "missing = for const declaration");
return nullptr;
@@ -404,11 +398,8 @@
for (;;) {
decos.push_back(std::move(deco));
- t = peek();
- if (!t.IsComma()) {
+ if (!match(Token::Type::kComma))
break;
- }
- next(); // consume the peek
deco = variable_decoration();
if (has_error()) {
@@ -549,12 +540,9 @@
// variable_decl
// : VAR variable_storage_decoration? variable_ident_decl
std::unique_ptr<ast::Variable> ParserImpl::variable_decl() {
- auto t = peek();
- if (!t.IsVar())
+ if (!match(Token::Type::kVar))
return nullptr;
- next(); // Consume the peek
-
auto sc = variable_storage_decoration();
if (has_error())
return {};
@@ -1043,12 +1031,9 @@
// variable_storage_decoration
// : LESS_THAN storage_class GREATER_THAN
ast::StorageClass ParserImpl::variable_storage_decoration() {
- auto t = peek();
- if (!t.IsLessThan())
+ if (!match(Token::Type::kLessThan))
return ast::StorageClass::kNone;
- next(); // Consume the peek
-
auto sc = storage_class();
if (has_error())
return sc;
@@ -1057,7 +1042,7 @@
return sc;
}
- t = next();
+ auto t = next();
if (!t.IsGreaterThan()) {
add_error(t, "missing > for variable decoration");
return ast::StorageClass::kNone;
@@ -1639,14 +1624,10 @@
// struct_member_decoration ATTR_RIGHT
bool ParserImpl::struct_member_decoration_decl(
ast::StructMemberDecorationList& decos) {
- auto t = peek();
- if (!t.IsAttrLeft()) {
+ if (!match(Token::Type::kAttrLeft))
return true;
- }
- next(); // Consume the peek
-
- t = peek();
+ auto t = peek();
if (t.IsAttrRight()) {
add_error(t, "empty struct member decoration found");
return false;
@@ -1910,14 +1891,12 @@
// function_header
// : FN IDENT PAREN_LEFT param_list PAREN_RIGHT ARROW function_type_decl
std::unique_ptr<ast::Function> ParserImpl::function_header() {
- auto t = peek();
- if (!t.IsFn())
+ auto source = peek().source();
+
+ if (!match(Token::Type::kFn))
return nullptr;
- auto source = t.source();
- next(); // Consume the peek
-
- t = next();
+ auto t = next();
if (!t.IsIdentifier()) {
add_error(t, "missing identifier for function");
return nullptr;
@@ -2218,16 +2197,13 @@
// return_stmt
// : RETURN logical_or_expression?
std::unique_ptr<ast::ReturnStatement> ParserImpl::return_stmt() {
- auto t = peek();
- if (!t.IsReturn())
+ auto source = peek().source();
+
+ if (!match(Token::Type::kReturn))
return nullptr;
- auto source = t.source();
- next(); // Consume the peek
-
std::unique_ptr<ast::Expression> expr = nullptr;
- t = peek();
- if (!t.IsSemicolon()) {
+ if (!peek().IsSemicolon()) {
expr = logical_or_expression();
if (has_error())
return nullptr;
@@ -2281,9 +2257,7 @@
if (var == nullptr)
return nullptr;
- t = peek();
- if (t.IsEqual()) {
- next(); // Consume the peek
+ if (match(Token::Type::kEqual)) {
auto constructor = logical_or_expression();
if (has_error())
return nullptr;
@@ -2301,12 +2275,10 @@
// if_stmt
// : IF paren_rhs_stmt body_stmt elseif_stmt? else_stmt?
std::unique_ptr<ast::IfStatement> ParserImpl::if_stmt() {
- auto t = peek();
- if (!t.IsIf())
- return nullptr;
+ auto source = peek().source();
- auto source = t.source();
- next(); // Consume the peek
+ if (!match(Token::Type::kIf))
+ return nullptr;
auto condition = paren_rhs_stmt();
if (has_error())
@@ -2393,12 +2365,10 @@
// switch_stmt
// : SWITCH paren_rhs_stmt BRACKET_LEFT switch_body+ BRACKET_RIGHT
std::unique_ptr<ast::SwitchStatement> ParserImpl::switch_stmt() {
- auto t = peek();
- if (!t.IsSwitch())
- return nullptr;
+ auto source = peek().source();
- auto source = t.source();
- next(); // Consume the peek
+ if (!match(Token::Type::kSwitch))
+ return nullptr;
auto condition = paren_rhs_stmt();
if (has_error())
@@ -2408,7 +2378,7 @@
return nullptr;
}
- t = next();
+ auto t = next();
if (!t.IsBraceLeft()) {
add_error(t, "missing { for switch statement");
return nullptr;
@@ -2543,14 +2513,12 @@
// loop_stmt
// : LOOP BRACKET_LEFT statements continuing_stmt? BRACKET_RIGHT
std::unique_ptr<ast::LoopStatement> ParserImpl::loop_stmt() {
- auto t = peek();
- if (!t.IsLoop())
+ auto source = peek().source();
+
+ if (!match(Token::Type::kLoop))
return nullptr;
- auto source = t.source();
- next(); // Consume the peek
-
- t = next();
+ auto t = next();
if (!t.IsBraceLeft()) {
add_error(t, "missing { for loop");
return nullptr;
@@ -2641,14 +2609,12 @@
// for_statement
// : FOR PAREN_LEFT for_header PAREN_RIGHT BRACE_LEFT statements BRACE_RIGHT
std::unique_ptr<ast::Statement> ParserImpl::for_stmt() {
- auto t = peek();
- if (!t.IsFor())
+ auto source = peek().source();
+
+ if (!match(Token::Type::kFor))
return nullptr;
- auto source = t.source();
- next(); // Consume the peek
-
- t = next();
+ auto t = next();
if (!t.IsParenLeft()) {
add_error(t, "missing for loop (");
return nullptr;
@@ -2760,33 +2726,30 @@
// break_stmt
// : BREAK
std::unique_ptr<ast::BreakStatement> ParserImpl::break_stmt() {
- auto t = peek();
- if (!t.IsBreak())
+ auto source = peek().source();
+
+ if (!match(Token::Type::kBreak))
return nullptr;
- next(); // Consume the peek
- return std::make_unique<ast::BreakStatement>(t.source());
+ return std::make_unique<ast::BreakStatement>(source);
}
// continue_stmt
// : CONTINUE
std::unique_ptr<ast::ContinueStatement> ParserImpl::continue_stmt() {
- auto t = peek();
- if (!t.IsContinue())
+ auto source = peek().source();
+
+ if (!match(Token::Type::kContinue))
return nullptr;
- next(); // Consume the peek
- return std::make_unique<ast::ContinueStatement>(t.source());
+ return std::make_unique<ast::ContinueStatement>(source);
}
// continuing_stmt
// : CONTINUING body_stmt
std::unique_ptr<ast::BlockStatement> ParserImpl::continuing_stmt() {
- auto t = peek();
- if (!t.IsContinuing()) {
+ if (!match(Token::Type::kContinuing))
return std::make_unique<ast::BlockStatement>();
- }
- next(); // Consume the peek
return body_stmt();
}