Files
carbon-lang/toolchain/check/handle_variable.cpp
T
Jon Ross-Perkins 0205645e7d Refactor BindName to support tracking the enclosing scope. (#3566)
This is a step towards adding enclosing scopes for imports. It creates
an indirection for all bind names.

We discussed specializing for bindings that are in function scope (i.e.,
not a useful enclosing scope for imports or diagnostics). However, the
thought is to go ahead with this singular approach for now, and only
change structure if it's a performance issues so that we have
incrementally fewer instructions to handle.
2024-01-05 02:56:03 +00:00

104 lines
3.8 KiB
C++

// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "toolchain/check/context.h"
#include "toolchain/check/convert.h"
#include "toolchain/check/modifiers.h"
#include "toolchain/sem_ir/inst.h"
namespace Carbon::Check {
auto HandleVariableIntroducer(Context& context,
Parse::VariableIntroducerId parse_node) -> bool {
// No action, just a bracketing node.
context.node_stack().Push(parse_node);
context.decl_state_stack().Push(DeclState::Var);
return true;
}
auto HandleReturnedModifier(Context& context,
Parse::ReturnedModifierId parse_node) -> bool {
// No action, just a bracketing node.
context.node_stack().Push(parse_node);
return true;
}
auto HandleVariableInitializer(Context& context,
Parse::VariableInitializerId parse_node)
-> bool {
// No action, just a bracketing node.
context.node_stack().Push(parse_node);
return true;
}
auto HandleVariableDecl(Context& context, Parse::VariableDeclId parse_node)
-> bool {
// Handle the optional initializer.
auto init_id = SemIR::InstId::Invalid;
Parse::NodeKind next_kind = context.node_stack().PeekParseNodeKind();
if (next_kind == Parse::NodeKind::TuplePattern) {
return context.TODO(parse_node, "tuple pattern in var");
}
// TODO: find a more robust way to determine if there was an initializer.
bool has_init = next_kind != Parse::NodeKind::BindingPattern;
if (has_init) {
init_id = context.node_stack().PopExpr();
context.node_stack()
.PopAndDiscardSoloParseNode<Parse::NodeKind::VariableInitializer>();
}
if (context.node_stack().PeekIs<Parse::NodeKind::TuplePattern>()) {
return context.TODO(parse_node, "tuple pattern in var");
}
// Extract the name binding.
auto value_id = context.node_stack().Pop<Parse::NodeKind::BindingPattern>();
if (auto bind_name = context.insts().Get(value_id).TryAs<SemIR::BindName>()) {
// Form a corresponding name in the current context, and bind the name to
// the variable.
auto name_context = context.decl_name_stack().MakeUnqualifiedName(
bind_name->parse_node,
context.bind_names().Get(bind_name->bind_name_id).name_id);
context.decl_name_stack().AddNameToLookup(name_context, value_id);
value_id = bind_name->value_id;
}
// Pop the `returned` specifier if present.
context.node_stack()
.PopAndDiscardSoloParseNodeIf<Parse::NodeKind::ReturnedModifier>();
// If there was an initializer, assign it to the storage.
if (has_init) {
if (context.GetCurrentScopeAs<SemIR::ClassDecl>()) {
// TODO: In a class scope, we should instead save the initializer
// somewhere so that we can use it as a default.
context.TODO(parse_node, "Field initializer");
} else {
init_id = Initialize(context, parse_node, value_id, init_id);
// TODO: Consider using different instruction kinds for assignment versus
// initialization.
context.AddInst(SemIR::Assign{parse_node, value_id, init_id});
}
}
context.node_stack()
.PopAndDiscardSoloParseNode<Parse::NodeKind::VariableIntroducer>();
// Process declaration modifiers.
CheckAccessModifiersOnDecl(context, Lex::TokenKind::Var);
LimitModifiersOnDecl(context, KeywordModifierSet::Access,
Lex::TokenKind::Var);
auto modifiers = context.decl_state_stack().innermost().modifier_set;
if (!!(modifiers & KeywordModifierSet::Access)) {
context.TODO(context.decl_state_stack().innermost().saw_access_modifier,
"access modifier");
}
context.decl_state_stack().Pop(DeclState::Var);
return true;
}
} // namespace Carbon::Check