Files
carbon-lang/toolchain/testing/compile_helper.cpp
T
Chandler Carruth 577fda1ca2 Speed up type literal lexing and make it more strict. (#4430)
This rejects type literals with more digits than we can lex without
APInt's help, and using a custom diagnostic. This is a pretty arbitrary
implementation limit, I'm wide open to even more strict rules here.

Despite no special casing and a very simplistic approach, by not using
APInt this completely eliminates the lexing overhead for `i32` in the
generated compilation benchmark where that specific type literal is very
common. We see a 10% improvement in lexing there:
```
BM_CompileAPIFileDenseDecls<Phase::Lex>/256        39.0µs ± 4%  34.8µs ± 2%  -10.86%  (p=0.000 n=19+20)
BM_CompileAPIFileDenseDecls<Phase::Lex>/1024        180µs ± 1%   158µs ± 2%  -12.22%  (p=0.000 n=18+20)
BM_CompileAPIFileDenseDecls<Phase::Lex>/4096        731µs ± 2%   641µs ± 1%  -12.31%  (p=0.000 n=18+20)
BM_CompileAPIFileDenseDecls<Phase::Lex>/16384      3.20ms ± 2%  2.86ms ± 2%  -10.47%  (p=0.000 n=18+19)
BM_CompileAPIFileDenseDecls<Phase::Lex>/65536      13.8ms ± 1%  12.4ms ± 2%   -9.78%  (p=0.000 n=18+19)
BM_CompileAPIFileDenseDecls<Phase::Lex>/262144     64.0ms ± 2%  58.4ms ± 2%   -8.70%  (p=0.000 n=19+18)
```

This starts to fix a TODO in the diagnostic for these by giving a
reasonably good diagnostic about a very large type literal. However, in
practice it regresses the diagnostics because error tokens produce noisy
extraneous diagnostics from parse and check currently. Leaving the TODO
there, and I have a follow-up PR to start improving the extraneous
diagnostics.
2024-10-24 21:43:35 +00:00

58 lines
2.2 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/testing/compile_helper.h"
namespace Carbon::Testing {
auto CompileHelper::GetTokenizedBuffer(llvm::StringRef text,
DiagnosticConsumer* consumer)
-> Lex::TokenizedBuffer& {
auto& source = GetSourceBuffer(text);
value_store_storage_.emplace_front();
token_storage_.push_front(Lex::Lex(value_store_storage_.front(), source,
consumer ? *consumer : consumer_));
return token_storage_.front();
}
auto CompileHelper::GetTokenizedBufferWithSharedValueStore(
llvm::StringRef text, DiagnosticConsumer* consumer)
-> std::pair<Lex::TokenizedBuffer&, SharedValueStores&> {
auto& tokens = GetTokenizedBuffer(text, consumer);
return {tokens, value_store_storage_.front()};
}
auto CompileHelper::GetTree(llvm::StringRef text) -> Parse::Tree& {
auto& tokens = GetTokenizedBuffer(text);
tree_storage_.push_front(Parse::Parse(tokens, consumer_,
/*vlog_stream=*/nullptr));
return tree_storage_.front();
}
auto CompileHelper::GetTreeAndSubtrees(llvm::StringRef text)
-> Parse::TreeAndSubtrees& {
auto& tree = GetTree(text);
tree_and_subtrees_storage_.push_front(
Parse::TreeAndSubtrees(token_storage_.front(), tree));
return tree_and_subtrees_storage_.front();
}
auto CompileHelper::GetTokenizedBufferWithTreeAndSubtrees(llvm::StringRef text)
-> std::pair<Lex::TokenizedBuffer&, Parse::TreeAndSubtrees&> {
auto& tree_and_subtrees = GetTreeAndSubtrees(text);
return {token_storage_.front(), tree_and_subtrees};
}
auto CompileHelper::GetSourceBuffer(llvm::StringRef text) -> SourceBuffer& {
std::string filename = llvm::formatv("test{0}.carbon", ++file_index_);
CARBON_CHECK(fs_.addFile(filename, /*ModificationTime=*/0,
llvm::MemoryBuffer::getMemBuffer(text)));
source_storage_.push_front(
std::move(*SourceBuffer::MakeFromFile(fs_, filename, consumer_)));
return source_storage_.front();
}
} // namespace Carbon::Testing