Files
carbon-lang/toolchain/semantics/semantics_node_block_stack.h
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

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2.9 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
#ifndef CARBON_TOOLCHAIN_SEMANTICS_SEMANTICS_NODE_BLOCK_STACK_H_
#define CARBON_TOOLCHAIN_SEMANTICS_SEMANTICS_NODE_BLOCK_STACK_H_
#include <type_traits>
#include "llvm/ADT/SmallVector.h"
#include "toolchain/semantics/semantics_ir.h"
#include "toolchain/semantics/semantics_node.h"
namespace Carbon::Check {
// Wraps the stack of node blocks for Context.
//
// All pushes and pops will be vlogged.
class NodeBlockStack {
public:
explicit NodeBlockStack(llvm::StringLiteral name, SemIR::File& semantics_ir,
llvm::raw_ostream* vlog_stream)
: name_(name), semantics_ir_(&semantics_ir), vlog_stream_(vlog_stream) {}
// Pushes an existing node block.
auto Push(SemIR::NodeBlockId id) -> void;
// Pushes a new node block. It will be invalid unless PeekForAdd is called in
// order to support lazy allocation.
auto Push() -> void { Push(SemIR::NodeBlockId::Invalid); }
// Pushes a new unreachable code block.
auto PushUnreachable() -> void { Push(SemIR::NodeBlockId::Unreachable); }
// Allocates and pushes a new node block.
auto PushForAdd() -> SemIR::NodeBlockId {
Push();
return PeekForAdd();
}
// Peeks at the top node block. This does not trigger lazy allocation, so the
// returned node block may be invalid.
auto Peek() -> SemIR::NodeBlockId {
CARBON_CHECK(!stack_.empty()) << "no current block";
return stack_.back();
}
// Returns the top node block, allocating one if it's still invalid.
auto PeekForAdd() -> SemIR::NodeBlockId;
// Pops the top node block. This will always return a valid node block;
// SemIR::NodeBlockId::Empty is returned if one wasn't allocated.
auto Pop() -> SemIR::NodeBlockId;
// Pops the top node block, ensuring that it is lazily allocated if it's
// empty. For use when more nodes will be added to the block later.
auto PopForAdd() -> SemIR::NodeBlockId {
PeekForAdd();
return Pop();
}
// Returns whether the current block is statically reachable.
auto is_current_block_reachable() -> bool {
return Peek() != SemIR::NodeBlockId::Unreachable;
}
// Prints the stack for a stack dump.
auto PrintForStackDump(llvm::raw_ostream& output) const -> void;
auto empty() const -> bool { return stack_.empty(); }
auto size() const -> size_t { return stack_.size(); }
private:
// A name for debugging.
llvm::StringLiteral name_;
// The underlying SemIR::File instance. Always non-null.
SemIR::File* semantics_ir_;
// Whether to print verbose output.
llvm::raw_ostream* vlog_stream_;
// The actual stack.
// PushEntry and PopEntry control modification in order to centralize
// vlogging.
llvm::SmallVector<SemIR::NodeBlockId> stack_;
};
} // namespace Carbon::Check
#endif // CARBON_TOOLCHAIN_SEMANTICS_SEMANTICS_NODE_BLOCK_STACK_H_