Files
carbon-lang/toolchain/check/handle_statement.cpp
T
Richard Smith c7a9e29a89 Add typed nodes to SemIR. (#3280)
Replace `SemIR::Node::GetAsFoo` and `SemIR::Node::Foo::Make` with
`SemIR::Foo` class that represents a particular kind of node, with named
fields.

Rename `SemIR::IntegerLiteral` and `SemIR::RealLiteral` to
`IntegerValue` / `RealValue` to better reflect their purpose and avoid a
name collision with the corresponding `SemIR` node kinds.

Remove `NodeKind::Invalid` and the `SemIR::Node` default constructor
entirely, as they were not used for anything.
2023-10-11 05:39:59 +00:00

94 lines
3.6 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/sem_ir/node.h"
namespace Carbon::Check {
// TODO: Find a better home for this. We'll likely need it for more than just
// expression statements.
static auto HandleDiscardedExpression(Context& context, SemIR::NodeId expr_id)
-> void {
// If we discard an initializing expression, convert it to a value or
// reference so that it has something to initialize.
auto expr = context.semantics_ir().GetNode(expr_id);
Convert(context, expr.parse_node(), expr_id,
{.kind = ConversionTarget::Discarded, .type_id = expr.type_id()});
// TODO: This will eventually need to do some "do not discard" analysis.
}
auto HandleExpressionStatement(Context& context, Parse::Node /*parse_node*/)
-> bool {
HandleDiscardedExpression(context, context.node_stack().PopExpression());
return true;
}
auto HandleReturnStatement(Context& context, Parse::Node parse_node) -> bool {
CARBON_CHECK(!context.return_scope_stack().empty());
auto fn_node = context.semantics_ir().GetNodeAs<SemIR::FunctionDeclaration>(
context.return_scope_stack().back());
const auto& callable =
context.semantics_ir().GetFunction(fn_node.function_id);
if (context.parse_tree().node_kind(context.node_stack().PeekParseNode()) ==
Parse::NodeKind::ReturnStatementStart) {
context.node_stack()
.PopAndDiscardSoloParseNode<Parse::NodeKind::ReturnStatementStart>();
if (callable.return_type_id.is_valid()) {
// TODO: Add a note pointing at the return type's parse node.
CARBON_DIAGNOSTIC(ReturnStatementMissingExpression, Error,
"Must return a {0}.", std::string);
context.emitter()
.Build(parse_node, ReturnStatementMissingExpression,
context.semantics_ir().StringifyType(callable.return_type_id))
.Emit();
}
context.AddNode(SemIR::Return(parse_node));
} else {
auto arg = context.node_stack().PopExpression();
context.node_stack()
.PopAndDiscardSoloParseNode<Parse::NodeKind::ReturnStatementStart>();
if (!callable.return_type_id.is_valid()) {
CARBON_DIAGNOSTIC(
ReturnStatementDisallowExpression, Error,
"No return expression should be provided in this context.");
CARBON_DIAGNOSTIC(ReturnStatementImplicitNote, Note,
"There was no return type provided.");
context.emitter()
.Build(parse_node, ReturnStatementDisallowExpression)
.Note(fn_node.parse_node, ReturnStatementImplicitNote)
.Emit();
} else if (callable.return_slot_id.is_valid()) {
arg = Initialize(context, parse_node, callable.return_slot_id, arg);
} else {
arg = ConvertToValueOfType(context, parse_node, arg,
callable.return_type_id);
}
context.AddNode(SemIR::ReturnExpression(parse_node, arg));
}
// Switch to a new, unreachable, empty node block. This typically won't
// contain any semantics IR, but it can do if there are statements following
// the `return` statement.
context.node_block_stack().Pop();
context.node_block_stack().PushUnreachable();
return true;
}
auto HandleReturnStatementStart(Context& context, Parse::Node parse_node)
-> bool {
// No action, just a bracketing node.
context.node_stack().Push(parse_node);
return true;
}
} // namespace Carbon::Check