mirror of
https://github.com/carbon-language/carbon-lang.git
synced 2026-09-24 22:02:23 +01:00
Jon Ross-Perkins
efa158d496
The use of ArrayStack here is intended to simplify the logic, and also make better use of the inst heap allocations. Prior changes #4101 and #4103 removed the less related logic from InstBlockStack, although #4103 is the actual part that blocked using ArrayStack. BTW, note the PrintForStackDump implementation was incorrect because it didn't apply size_. This simplification fixes the issue.
102 lines
3.6 KiB
C++
102 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
|
|
|
|
#ifndef CARBON_TOOLCHAIN_CHECK_INST_BLOCK_STACK_H_
|
|
#define CARBON_TOOLCHAIN_CHECK_INST_BLOCK_STACK_H_
|
|
|
|
#include "common/array_stack.h"
|
|
#include "llvm/ADT/SmallVector.h"
|
|
#include "toolchain/sem_ir/file.h"
|
|
|
|
namespace Carbon::Check {
|
|
|
|
// A stack of instruction blocks that are currently being constructed in a
|
|
// Context. The contents of the instruction blocks are stored here until the
|
|
// instruction block is popped from the stack, at which point they are
|
|
// transferred into the SemIR::File for long-term storage.
|
|
//
|
|
// All pushes and pops will be vlogged.
|
|
class InstBlockStack {
|
|
public:
|
|
explicit InstBlockStack(llvm::StringLiteral name, SemIR::File& sem_ir,
|
|
llvm::raw_ostream* vlog_stream)
|
|
: name_(name), sem_ir_(&sem_ir), vlog_stream_(vlog_stream) {}
|
|
|
|
// Pushes an existing instruction block.
|
|
auto Push(SemIR::InstBlockId id) -> void;
|
|
|
|
// Pushes an existing instruction block with a set of instructions.
|
|
auto Push(SemIR::InstBlockId id, llvm::ArrayRef<SemIR::InstId> inst_ids)
|
|
-> void;
|
|
|
|
// Pushes a new instruction block. It will be invalid unless PeekOrAdd is
|
|
// called in order to support lazy allocation.
|
|
auto Push() -> void { Push(SemIR::InstBlockId::Invalid); }
|
|
|
|
// Pushes a new unreachable code block.
|
|
auto PushUnreachable() -> void { Push(SemIR::InstBlockId::Unreachable); }
|
|
|
|
// Returns the ID of the top instruction block, allocating one if necessary.
|
|
// If `depth` is specified, returns the instruction at `depth` levels from the
|
|
// top of the stack instead of the top block, where the top block is at depth
|
|
// 0.
|
|
auto PeekOrAdd(int depth = 0) -> SemIR::InstBlockId;
|
|
|
|
// Pops the top instruction block. This will always return a valid instruction
|
|
// block; SemIR::InstBlockId::Empty is returned if one wasn't allocated.
|
|
auto Pop() -> SemIR::InstBlockId;
|
|
|
|
// Pops the top instruction block, and discards it if it hasn't had an ID
|
|
// allocated.
|
|
auto PopAndDiscard() -> void;
|
|
|
|
// Adds the given instruction ID to the block at the top of the stack.
|
|
auto AddInstId(SemIR::InstId inst_id) -> void {
|
|
CARBON_CHECK(!empty()) << "no current block";
|
|
insts_stack_.AppendToTop(inst_id);
|
|
}
|
|
|
|
// Returns whether the current block is statically reachable.
|
|
auto is_current_block_reachable() -> bool {
|
|
return id_stack_.back() != SemIR::InstBlockId::Unreachable;
|
|
}
|
|
|
|
// Returns a view of the contents of the top instruction block on the stack.
|
|
auto PeekCurrentBlockContents() const -> llvm::ArrayRef<SemIR::InstId> {
|
|
CARBON_CHECK(!empty()) << "no current block";
|
|
return insts_stack_.PeekArray();
|
|
}
|
|
|
|
// Prints the stack for a stack dump.
|
|
auto PrintForStackDump(llvm::raw_ostream& output) const -> void;
|
|
|
|
// Runs verification that the processing cleanly finished.
|
|
auto VerifyOnFinish() const -> void {
|
|
CARBON_CHECK(empty()) << id_stack_.size();
|
|
}
|
|
|
|
auto empty() const -> bool { return id_stack_.empty(); }
|
|
|
|
private:
|
|
// A name for debugging.
|
|
llvm::StringLiteral name_;
|
|
|
|
// The underlying SemIR::File instance. Always non-null.
|
|
SemIR::File* sem_ir_;
|
|
|
|
// Whether to print verbose output.
|
|
llvm::raw_ostream* vlog_stream_;
|
|
|
|
// The stack of block IDs. Valid if allocated, Invalid if no block has been
|
|
// allocated, or Unreachable if this block is known to be unreachable.
|
|
llvm::SmallVector<SemIR::InstBlockId> id_stack_;
|
|
|
|
// The stack of insts in each block.
|
|
ArrayStack<SemIR::InstId> insts_stack_;
|
|
};
|
|
|
|
} // namespace Carbon::Check
|
|
|
|
#endif // CARBON_TOOLCHAIN_CHECK_INST_BLOCK_STACK_H_
|