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2021-03-06Change x64 size checks to not apply to x32.Harald van Dijk-1/+1
Rust contains various size checks conditional on target_arch = "x86_64", but these checks were never intended to apply to x86_64-unknown-linux-gnux32. Add target_pointer_width = "64" to the conditions.
2021-01-22Refactor token collection to capture trailing token immediatelyAaron Hill-11/+0
2021-01-03Edit rustc_ast::tokenstream docspierwill-16/+17
Fix some punctuation and wording, and add intra-documentation links.
2020-12-29Remove pretty-print/reparse hack, and add derive-specific hackAaron Hill-0/+6
2020-11-26Properly handle attributes on statementsAaron Hill-0/+11
We now collect tokens for the underlying node wrapped by `StmtKind` instead of storing tokens directly in `Stmt`. `LazyTokenStream` now supports capturing a trailing semicolon after it is initially constructed. This allows us to avoid refactoring statement parsing to wrap the parsing of the semicolon in `parse_tokens`. Attributes on item statements (e.g. `fn foo() { #[bar] struct MyStruct; }`) are now treated as item attributes, not statement attributes, which is consistent with how we handle attributes on other kinds of statements. The feature-gating code is adjusted so that proc-macro attributes are still allowed on item statements on stable. Two built-in macros (`#[global_allocator]` and `#[test]`) needed to be adjusted to support being passed `Annotatable::Stmt`.
2020-11-13Reserve space in advanceDániel Buga-1/+1
2020-11-03Expand `NtExpr` tokens only in key-value attributesVadim Petrochenkov-0/+34
2020-11-01Do not remove tokens before AST json serializationVadim Petrochenkov-2/+3
2020-10-31parser: Cleanup `LazyTokenStream` and avoid some clonesVadim Petrochenkov-43/+22
by using a named struct instead of a closure.
2020-10-21Auto merge of #77250 - Aaron1011:feature/flat-token-collection, r=petrochenkovbors-1/+73
Rewrite `collect_tokens` implementations to use a flattened buffer Instead of trying to collect tokens at each depth, we 'flatten' the stream as we go allong, pushing open/close delimiters to our buffer just like regular tokens. One capturing is complete, we reconstruct a nested `TokenTree::Delimited` structure, producing a normal `TokenStream`. The reconstructed `TokenStream` is not created immediately - instead, it is produced on-demand by a closure (wrapped in a new `LazyTokenStream` type). This closure stores a clone of the original `TokenCursor`, plus a record of the number of calls to `next()/next_desugared()`. This is sufficient to reconstruct the tokenstream seen by the callback without storing any additional state. If the tokenstream is never used (e.g. when a captured `macro_rules!` argument is never passed to a proc macro), we never actually create a `TokenStream`. This implementation has a number of advantages over the previous one: * It is significantly simpler, with no edge cases around capturing the start/end of a delimited group. * It can be easily extended to allow replacing tokens an an arbitrary 'depth' by just using `Vec::splice` at the proper position. This is important for PR #76130, which requires us to track information about attributes along with tokens. * The lazy approach to `TokenStream` construction allows us to easily parse an AST struct, and then decide after the fact whether we need a `TokenStream`. This will be useful when we start collecting tokens for `Attribute` - we can discard the `LazyTokenStream` if the parsed attribute doesn't need tokens (e.g. is a builtin attribute). The performance impact seems to be neglibile (see https://github.com/rust-lang/rust/pull/77250#issuecomment-703960604). There is a small slowdown on a few benchmarks, but it only rises above 1% for incremental builds, where it represents a larger fraction of the much smaller instruction count. There a ~1% speedup on a few other incremental benchmarks - my guess is that the speedups and slowdowns will usually cancel out in practice.
2020-10-19Rewrite `collect_tokens` implementations to use a flattened bufferAaron Hill-1/+73
Instead of trying to collect tokens at each depth, we 'flatten' the stream as we go allong, pushing open/close delimiters to our buffer just like regular tokens. One capturing is complete, we reconstruct a nested `TokenTree::Delimited` structure, producing a normal `TokenStream`. The reconstructed `TokenStream` is not created immediately - instead, it is produced on-demand by a closure (wrapped in a new `LazyTokenStream` type). This closure stores a clone of the original `TokenCursor`, plus a record of the number of calls to `next()/next_desugared()`. This is sufficient to reconstruct the tokenstream seen by the callback without storing any additional state. If the tokenstream is never used (e.g. when a captured `macro_rules!` argument is never passed to a proc macro), we never actually create a `TokenStream`. This implementation has a number of advantages over the previous one: * It is significantly simpler, with no edge cases around capturing the start/end of a delimited group. * It can be easily extended to allow replacing tokens an an arbitrary 'depth' by just using `Vec::splice` at the proper position. This is important for PR #76130, which requires us to track information about attributes along with tokens. * The lazy approach to `TokenStream` construction allows us to easily parse an AST struct, and then decide after the fact whether we need a `TokenStream`. This will be useful when we start collecting tokens for `Attribute` - we can discard the `LazyTokenStream` if the parsed attribute doesn't need tokens (e.g. is a builtin attribute). The performance impact seems to be neglibile (see https://github.com/rust-lang/rust/pull/77250#issuecomment-703960604). There is a small slowdown on a few benchmarks, but it only rises above 1% for incremental builds, where it represents a larger fraction of the much smaller instruction count. There a ~1% speedup on a few other incremental benchmarks - my guess is that the speedups and slowdowns will usually cancel out in practice.
2020-10-19Avoid cloning the contents of a `TokenStream` in a few placesAaron Hill-5/+5
2020-10-14Remove unused code from rustc_astest31-6/+0
2020-09-03Rename IsJoint -> SpacingAleksey Kladov-22/+19
To match better naming from proc-macro
2020-08-30mv compiler to compiler/mark-0/+433