mirror of
https://github.com/carbon-language/carbon-lang.git
synced 2026-10-05 14:41:06 +01:00
Richard Smith
c78751338b
Add support for "jump to declaration", "find references", type information on hover. This support is strictly single-file for now; only references and declarations within the same file are found. We could go a bit beyond that, but to properly handle cross-file references we'll need to build an index and a compilation database, which is beyond the scope of this change. On hover, we provide the type information for the instruction under the cursor as-is. This is frequently not very useful, as the type of a function F is simply "<type of F>", but is a starting point for richer information. Assisted-by: Claude Code
70 lines
3.1 KiB
C++
70 lines
3.1 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_LANGUAGE_SERVER_SEM_IR_INDEX_H_
|
|
#define CARBON_TOOLCHAIN_LANGUAGE_SERVER_SEM_IR_INDEX_H_
|
|
|
|
#include "llvm/ADT/ArrayRef.h"
|
|
#include "llvm/ADT/SmallVector.h"
|
|
#include "toolchain/lex/token_index.h"
|
|
#include "toolchain/lex/tokenized_buffer.h"
|
|
#include "toolchain/parse/node_ids.h"
|
|
#include "toolchain/parse/tree_and_subtrees.h"
|
|
#include "toolchain/sem_ir/file.h"
|
|
|
|
namespace Carbon::LanguageServer {
|
|
|
|
// Returns the token that identifies `node_id`: the name it declares, if it
|
|
// declares one, and otherwise the node's own token.
|
|
//
|
|
// A declaration's own token is wherever the parser finished it -- the `{` of a
|
|
// function body, or the `:` of a binding -- which is not what a user points at
|
|
// to mean that declaration. Requests are answered at the name instead, so both
|
|
// the index and the locations we report are keyed on it.
|
|
auto GetNameToken(const Parse::TreeAndSubtrees& tree_and_subtrees,
|
|
Parse::NodeId node_id) -> Lex::TokenIndex;
|
|
|
|
// Maps each token to the instructions that were checked from it.
|
|
//
|
|
// Position-based requests such as `hover` and `definition` all start from a
|
|
// source position, so this is keyed by token rather than by parse node: the
|
|
// caller has to find the token for a position anyway, and the parse node is
|
|
// recoverable from an instruction's `LocId`. Instructions imported from other
|
|
// files are excluded, because their locations refer to another file's parse
|
|
// tree rather than to a token in this one.
|
|
//
|
|
// Build this lazily, on the first query after the file's text changes. Building
|
|
// costs the same single pass over the instructions that an unindexed scan
|
|
// would, and most text changes are never followed by a query, so building
|
|
// eagerly would only add work to the latency-sensitive path that produces
|
|
// diagnostics.
|
|
class SemIRIndex {
|
|
public:
|
|
explicit SemIRIndex(const SemIR::File& sem_ir,
|
|
const Parse::TreeAndSubtrees& tree_and_subtrees);
|
|
|
|
// Returns the instructions checked from `token`, in `InstId` order. Returns
|
|
// an empty list for a token that produced no instructions, which is common:
|
|
// punctuation and keywords usually contribute to an enclosing instruction
|
|
// rather than producing one of their own.
|
|
auto InstsForToken(Lex::TokenIndex token) const
|
|
-> llvm::ArrayRef<SemIR::InstId>;
|
|
|
|
private:
|
|
// Instructions grouped by token, in the compressed-sparse-row layout: the
|
|
// group for token `i` is `insts_[token_starts_[i] .. token_starts_[i + 1])`.
|
|
// `token_starts_` therefore has one more entry than there are tokens.
|
|
//
|
|
// Token indices are dense, so this is built by counting sort in a single pass
|
|
// over the instructions, and looked up in constant time. A hash map would
|
|
// need to handle the many-instructions-per-token case explicitly; here it
|
|
// falls out of the layout.
|
|
llvm::SmallVector<SemIR::InstId, 0> insts_;
|
|
llvm::SmallVector<int32_t, 0> token_starts_;
|
|
};
|
|
|
|
} // namespace Carbon::LanguageServer
|
|
|
|
#endif // CARBON_TOOLCHAIN_LANGUAGE_SERVER_SEM_IR_INDEX_H_
|