Re-export more rustc_span::symbol things from rustc_span.

[nnethercote]

rustc_span::symbol defines some things that are re-exported from rustc_span, such as Symbol and sym. But it doesn't re-export some closely related things such as Ident and kw. So you can do use rustc_span::{Symbol, sym} but you have to do use rustc_span::symbol::{Ident, kw}, which is inconsistent for no good reason.

This commit re-exports Ident, kw, and MacroRulesNormalizedIdent, and changes many rustc_span::symbol:: qualifiers to rustc_span::. This is a 300+ net line of code reduction, mostly because many files with two use rustc_span items can be reduced to one.

r? @jieyouxu

[rustbot]

Some changes occurred in cfg and check-cfg configuration

cc @Urgau

rustc_macros::diagnostics was changed

cc @davidtwco, @compiler-errors, @TaKO8Ki

Some changes occurred in need_type_info.rs

cc @lcnr

HIR ty lowering was modified

cc @fmease

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

This PR changes MIR

cc @oli-obk, @RalfJung, @JakobDegen, @davidtwco, @celinval, @vakaras

Some changes occurred in src/tools/rustfmt

cc @rust-lang/rustfmt

Some changes occurred to the CTFE machinery

cc @rust-lang/wg-const-eval

Some changes occurred in match lowering

cc @Nadrieril

Some changes occurred in check-cfg diagnostics

cc @Urgau

These commits modify compiler targets.
(See the Target Tier Policy.)

Some changes occurred in compiler/rustc_codegen_cranelift

cc @bjorn3

Some changes occurred in src/tools/clippy

cc @rust-lang/clippy

Some changes occurred to the CTFE / Miri interpreter

cc @rust-lang/miri

[nnethercote]

Sorry for the tedious review. This is the line of note. The rest is just shortening rustc_span::symbol:: qualifiers.

[oli-obk]

I don't think I find this valuable. Reducing/merging imports is not very useful imo unless it allows removing of crate deps via reexports

[nnethercote]

I do think it's valuable. I think it's silly that you can import Symbol and sym via rustc_span, but the extremely similar things Ident and kw must be imported via rustc_span::symbol. It's one of those annoying rough edges and it shows up in a zillion files.

[jieyouxu]

I don't feel too strongly either way since the nesting doesn't seem very steep. Anyway, I'll look at this tmrw since there's several files to go through.

[ytmimi]

@nnethercote I'd like to opt out of these changes for rustfmt.

[bors]

☔ The latest upstream changes (presumably #133099) made this pull request unmergeable. Please resolve the merge conflicts.

[jieyouxu]

Thanks for the PR. I looked at the changes individually:

• We should drop rustfmt changes as @ytmimi requested.
• We should ask T-rustdoc if they want to opt-in to the rustdoc import changes (or at least in this PR).
• We should ask T-clippy if they want to opt-in to the clippy import changes (or at least in this PR).
• Compiler changes seem reasonable to me. If we want to make the re-exports/imports of {Ident, kw, sym} by downstream compiler crates and tool users more consistent, I guess better get it done earlier than later.

[nnethercote]

The diff from this file sums up the motivation for this change:

diff --git a/compiler/rustc_ast_lowering/src/format.rs b/compiler/rustc_ast_lowering/src/format.rs
index 653116e1fe0..22aa1e6fc20 100644
--- a/compiler/rustc_ast_lowering/src/format.rs
+++ b/compiler/rustc_ast_lowering/src/format.rs
@@ -6,8 +6,7 @@
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_hir as hir;
 use rustc_session::config::FmtDebug;
-use rustc_span::symbol::{Ident, kw};
-use rustc_span::{Span, Symbol, sym};
+use rustc_span::{Ident, Span, Symbol, kw, sym};

 use super::LoweringContext;

It's silly that Symbol gets a shortcut import but the closely related Ident doesn't. Likewise, sym gets a shortcut but the closely related kw does not.

[bors]

☔ The latest upstream changes (presumably #134414) made this pull request unmergeable. Please resolve the merge conflicts.

[jieyouxu]

@nnethercote if you don't want to wait for T-clippy/T-rustdoc, we could also split this PR into compiler-only changes vs tools changes, where the tool changes can be sent to the relevant teams. I can r+ the compiler changes specifically.

[nnethercote]

I've trimmed this down to just the compiler changes and rebased. It's conflict-prone, so:

@bors r=jieyouxu p=1

[bors]

📌 Commit 2620eb4 has been approved by jieyouxu

It is now in the queue for this repository.

[rust-log-analyzer]

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[bors]

⌛ Testing commit 2620eb4 with merge a89ca2c...

[bors]

☀️ Test successful - checks-actions
Approved by: jieyouxu
Pushing a89ca2c to master...

[rust-timer]

Finished benchmarking commit (a89ca2c): comparison URL.

Overall result: ❌ regressions - no action needed

@rustbot label: -perf-regression

Instruction count

This is the most reliable metric that we have; it was used to determine the overall result at the top of this comment. However, even this metric can sometimes exhibit noise.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	0.9%	[0.9%, 0.9%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (secondary 2.1%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.1%	[2.1%, 2.1%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Cycles

Results (secondary -4.9%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-4.9%	[-4.9%, -4.9%]	2
All ❌✅ (primary)	-	-	0

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 768.784s -> 769.265s (0.06%)
Artifact size: 330.32 MiB -> 330.34 MiB (0.01%)