better ObligationCause for normalization errors in `can_type_implement_copy`

Some logic is needed so we can point to the field when given totally nonsense types like `struct Foo(<u32 as Iterator>::Item);`

Fixes #93687

resolve/metadata: Stop encoding macros as reexports

Supersedes https://github.com/rust-lang/rust/pull/88335.
r? `@cjgillot`

To make the `macro_rules` flag more readily available without decoding everything else

Previously it always returned `MacroKind::Bang` while some of those macros are actually attributes and derives

Always format to internal String in FmtPrinter

This avoids monomorphizing for different parameters, decreasing generic code
instantiated downstream from rustc_middle -- locally seeing 7% unoptimized LLVM IR
line wins on rustc_borrowck, for example.

We likely can't/shouldn't get rid of the Result-ness on most functions, though some
further cleanup avoiding fmt::Error where we now know it won't occur may be possible,
though somewhat painful -- fmt::Write is a pretty annoying API to work with in practice
when you're trying to use it infallibly.

Partially move cg_ssa towards using a single builder

Not all codegen backends can handle hopping between blocks well. For example Cranelift requires blocks to be terminated before switching to building a new block. Rust-gpu requires a `RefCell` to allow hopping between blocks and cg_gcc currently has a buggy implementation of hopping between blocks. This PR reduces the amount of cases where cg_ssa switches between blocks before they are finished and mostly fixes the block hopping in cg_gcc. (~~only `scalar_to_backend` doesn't handle it correctly yet in cg_gcc~~ fixed that one.)

`@antoyo` please review the cg_gcc changes.

Back more metadata using per-query tables

r? `@ghost`

Rollup of 9 pull requests

Successful merges:

 - #89887 (Change `char` type in debuginfo to DW_ATE_UTF)
 - #94267 (Remove unused ordering derivations and bounds for `SimplifiedTypeGen`)
 - #94270 (Miri: relax fn ptr check)
 - #94273 (add matching doc to errorkind)
 - #94283 (remove feature gate in control_flow examples)
 - #94288 (Cleanup a few Decoder methods)
 - #94292 (riscv32imc_esp_espidf: set max_atomic_width to 64)
 - #94296 (⬆ rust-analyzer)
 - #94300 (Fix a typo in documentation of `array::IntoIter::new_unchecked`)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Fix a typo in documentation of `array::IntoIter::new_unchecked`

🌸

⬆ rust-analyzer

r? `@ghost`

riscv32imc_esp_espidf: set max_atomic_width to 64

For espidf targets without native atomics, there is atomic emulation inside [the newlib component of espidf](https://github.com/espressif/esp-idf/blob/master/components/newlib/stdatomic.c), this has been extended to support emulation up to 64bits therefore we are safe to increase the atomic width for the `riscv32imc_esp_espidf` target.

Closes https://github.com/esp-rs/rust/issues/107

cc: `@ivmarkov`

Cleanup a few Decoder methods

This is just some simple follow up to #93839.

r? `@nnethercote`

remove feature gate in control_flow examples

Stabilization was done in https://github.com/rust-lang/rust/pull/91091, but the two examples weren't updated accordingly.

Probably too late to put it into stable, but it should be in the next release :)

add matching doc to errorkind

Rework of #90706

Miri: relax fn ptr check

As discussed in https://github.com/rust-lang/unsafe-code-guidelines/issues/72#issuecomment-1025407536, the function pointer check done by Miri is currently overeager: contrary to our usual principle of only checking rather uncontroversial validity invariants, we actually check that the pointer points to a real function.

So, this relaxes the check to what the validity invariant probably will be (and what the reference already says it is): the function pointer must be non-null, and that's it.

The check that CTFE does on the final value of a constant is unchanged -- CTFE recurses through references, so it makes some sense to also recurse through function pointers. We might still want to relax this in the future, but that would be a separate change.

r? `@oli-obk`

Remove unused ordering derivations and bounds for `SimplifiedTypeGen`

This is another small PR clearing the way for work on #90317.

Change `char` type in debuginfo to DW_ATE_UTF

Rust previously encoded the `char` type as DW_ATE_unsigned_char. The more appropriate encoding is `DW_ATE_UTF`.

Clang also uses the DW_ATE_UTF for `char32_t` in C++.

This fixes the display of the `char` type in the Windows debuggers. Without this change, the variable did not show in the locals window.
![image](https://user-images.githubusercontent.com/704597/137368067-9b3e4dc8-a075-44ba-a687-bf3810a44e5a.png)

LLDB 13 is also able to display the char value, when before it failed with `need to add support for DW_TAG_base_type 'char' encoded with DW_ATE = 0x8, bit_size = 32`

r? `@wesleywiser`

Reapply cg_llvm: `fewer_names` in `uncached_llvm_type`

r? `@davidtwco` `@erikdesjardins`

Node id to hir id refactor

Related to #89278

r? `@oli-obk`

Co-authored-by: NJosh Triplett <josh@joshtriplett.org>

Rollup of 12 pull requests

Successful merges:

 - #94128 (rustdoc: several minor fixes)
 - #94137 (rustdoc-json: Better Header Type)
 - #94213 (fix names in feature(...) suggestion)
 - #94240 (Suggest calling .display() on `PathBuf` too)
 - #94253 (Use 2021 edition in ./x.py fmt)
 - #94259 (Bump download-ci-llvm-stamp for llvm-nm inclusion)
 - #94260 (Fix rustdoc infinite redirection generation)
 - #94263 (Typo fix: Close inline-code backtick)
 - #94264 (Fix typo.)
 - #94271 (Miri: extend comments on downcast operation)
 - #94280 (Rename `region_should_not_be_omitted` to `should_print_region`)
 - #94285 (Sync rustc_codegen_cranelift)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Rust previously encoded the `char` type as DW_ATE_unsigned_char. The more
appropriate encoding is DW_ATE_UTF.

Clang uses this same debug encoding for char32_t.

This fixes the display of `char` types in Windows debuggers as well as LLDB.

Sync rustc_codegen_cranelift

r? `@ghost`

`@rustbot` label +A-codegen +A-cranelift +T-compiler

Rename `region_should_not_be_omitted` to `should_print_region`

to avoid double negation

Miri: extend comments on downcast operation

r? `@oli-obk`

Fix typo.

Yeah just a typo (probably some breaking changes in here be careful) :)

Typo fix: Close inline-code backtick

A drop in the ocean.

Fix rustdoc infinite redirection generation

Someone came to me about a funny bug they had when clicking on any link on [this page](https://world.pages.gitlab.gnome.org/Rust/libadwaita-rs/stable/latest/docs/libadwaita/builders/index.html): it ended one page redirecting to itself indefinitely.

I was able to make a minimum reproducible case to trigger this bug which I now use as a test.

r? ``@notriddle``

Bump download-ci-llvm-stamp for llvm-nm inclusion

We started using it in https://github.com/rust-lang/rust/pull/94023.