Files
carbon-lang/toolchain/semantics/semantics_handle_if_expression.cpp
T
Jon Ross-Perkins 67da700dd5 Split Semantics into Check and SemIR namespaces (#3138)
Splits IR files into SemIR, and logic files into Check. These will be
split into separate directories as part of a later move; the namespaces
are being done first in order to vet the switch, and hopefully make
conflicts a little easier to manage due to the substantial renames.

A lot of this is just automated removal of Semantics prefixes from
names, adding namespace references where needed. A few special-cases
are:

- SemanticsIR -> SemIR::File
- A few things were discussed, like Unit, CompileUnit, or CompiledUnit.
Unit was too vague for chandlerc, and I thought CompileUnit might lead
to incorrect inferences (CompilationUnit would be more precise, but
typically written as SemIR::CompilationUnit which is pretty long). File
seemed to be a short name that we could agree on.
- SemanticsIRFormatter -> SemIR::Formatter
- FormatSemanticsIR -> SemIR::FormatFile
- SemanticsFileTest -> CheckFileTest
- It remains in the Testing namespace, where just "FileTest" might be
too broad a name.
- SemanticsDeclarationNameStack::Context ->
Check::DeclarationNameStack::NameContext
  - This avoids a Check::Context name shadowing.

Changes check_internal.h to include ostream.h to improve finding of
Print/operator<< (otherwise it didn't compile).

This is part of #3070
2023-08-23 22:51:23 +00:00

64 lines
2.4 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/semantics/semantics_context.h"
namespace Carbon::Check {
auto HandleIfExpressionIf(Context& context, ParseTree::Node if_node) -> bool {
auto cond_value_id = context.node_stack().PopExpression();
context.node_stack().Push(if_node);
// Convert the condition to `bool`, and branch on it.
cond_value_id = context.ImplicitAsBool(if_node, cond_value_id);
auto then_block_id =
context.AddDominatedBlockAndBranchIf(if_node, cond_value_id);
auto else_block_id = context.AddDominatedBlockAndBranch(if_node);
// Push the `else` block and `then` block, and start emitting the `then`.
context.node_block_stack().Pop();
context.node_block_stack().Push(else_block_id);
context.node_block_stack().Push(then_block_id);
context.AddCurrentCodeBlockToFunction();
return true;
}
auto HandleIfExpressionThen(Context& context, ParseTree::Node then_node)
-> bool {
context.node_stack().Push(then_node, context.node_block_stack().Pop());
context.AddCurrentCodeBlockToFunction();
return true;
}
auto HandleIfExpressionElse(Context& context, ParseTree::Node else_node)
-> bool {
auto else_value_id = context.node_stack().PopExpression();
auto [then_node, then_end_block_id] =
context.node_stack().PopWithParseNode<ParseNodeKind::IfExpressionThen>();
auto then_value_id = context.node_stack().PopExpression();
auto if_node =
context.node_stack().PopForSoloParseNode<ParseNodeKind::IfExpressionIf>();
// Convert the `else` value to the `then` value's type, and finish the `else`
// block.
// TODO: Find a common type, and convert both operands to it instead.
auto result_type_id = context.semantics_ir().GetNode(then_value_id).type_id();
else_value_id =
context.ImplicitAsRequired(else_node, else_value_id, result_type_id);
auto else_end_block_id = context.node_block_stack().Pop();
// Create a resumption block and branches to it.
auto chosen_value_id = context.AddConvergenceBlockWithArgAndPush(
if_node,
{{then_end_block_id, then_value_id}, {else_end_block_id, else_value_id}});
context.AddCurrentCodeBlockToFunction();
// Push the result value.
context.node_stack().Push(else_node, chosen_value_id);
return true;
}
} // namespace Carbon::Check