rust/library
bors afa9fef709 Auto merge of #112418 - ferrocene:pa-mir-opt-panic, r=ozkanonur,saethlin
Add support for targets without unwinding in `mir-opt`, and improve `--bless` for it

The main goal of this PR is to add support for targets without unwinding support in the `mir-opt` test suite, by adding the `EMIT_MIR_FOR_EACH_PANIC_STRATEGY` comment. Similarly to 32bit vs 64bit, when that comment is present, blessed output files will have the `.panic-unwind` or `.panic-abort` suffix, and the right one will be chosen depending on the target's panic strategy.

The `EMIT_MIR_FOR_EACH_PANIC_STRATEGY` comment replaced all the `ignore-wasm32` comments in the `mir-opt` test suite, as those comments were added due to `wasm32` being a target without unwinding support. The comment was also added on other tests that were only executed on x86 but were still panic strategy dependent.

The `mir-opt` suite was then blessed, which caused a ton of churn as most of the existing output files had to be renamed and (mostly) duplicated with the abort strategy.

---

After [asking on Zulip](https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/mir-opt.20tests.20and.20panic.3Dabort), the main concern about this change is it'd make blessing the `mir-opt` suite even harder, as you'd need to both bless it with an unwinding target and an aborting target. This exacerbated the current situation, where you'd need to bless it with a 32bit and a 64bit target already.

Because of that, this PR also makes significant enhancements to `--bless` for the `mir-opt` suite, where it will automatically bless the suite four times with different targets, while requiring minimal cross-compilation.

To handle the 32bit vs 64bit blessing, there is now an hardcoded list of target mapping between 32bit and 64bit. The goal of the list is to find a related target that will *probably* work without requiring additional cross-compilation toolchains on the system. If a mapping is found, bootstrap will bless the suite with both targets, otherwise just with the current target.

To handle the panic strategy blessing (abort vs unwind), I had to resort to what I call "synthetic targets". For each of the target we're blessing (so either the current one, or a 32bit and a 64bit depending on the previous paragraph), bootstrap will extract the JSON spec of the target and change it to include `"panic-strategy": "abort"`. It will then build the standard library with this synthetic target, and bless the `mir-opt` suite with it.

As a result of these changes, blessing the `mir-opt` suite will actually bless it two or four times with different targets, ensuring all possible variants are actually blessed.

---

This PR is best reviewed commit-by-commit.

r? `@jyn514`
cc `@saethlin` `@oli-obk`
2023-06-14 14:20:59 +00:00
..
alloc Auto merge of #112314 - ferrocene:pa-core-alloc-abort, r=bjorn3 2023-06-13 19:03:27 +00:00
backtrace@4245978ca8 PS Vita std support 2023-05-07 18:57:43 +03:00
core Auto merge of #112314 - ferrocene:pa-core-alloc-abort, r=bjorn3 2023-06-13 19:03:27 +00:00
panic_abort Remove unnecessary raw pointer in __rust_start_panic arg 2023-03-26 16:40:18 +00:00
panic_unwind Partial stabilisation of c_unwind 2023-04-29 13:01:44 +01:00
portable-simd Explicit set workspace.resolver = "1" 2023-05-31 00:08:11 +01:00
proc_macro fix TODO comments 2023-05-02 10:32:07 +00:00
profiler_builtins Fully stabilize NLL 2022-06-03 17:16:41 -04:00
rtstartup Remove custom frame info registration on i686-pc-windows-gnu 2022-08-23 16:12:58 +08:00
rustc-std-workspace-alloc Replace libstd, libcore, liballoc in line comments. 2022-12-30 14:00:42 +01:00
rustc-std-workspace-core Switch all libraries to the 2021 edition 2021-12-23 19:03:47 +08:00
rustc-std-workspace-std Switch all libraries to the 2021 edition 2021-12-23 19:03:47 +08:00
std Auto merge of #112418 - ferrocene:pa-mir-opt-panic, r=ozkanonur,saethlin 2023-06-14 14:20:59 +00:00
stdarch@7e2cdc675b stdarch: update submodule, take 5 2023-05-08 19:03:55 +09:00
sysroot Add a sysroot crate to represent the standard library crates 2023-04-25 13:40:36 +02:00
test ignore core, alloc and test tests that require unwinding on panic=abort 2023-06-13 15:53:24 +02:00
unwind Rollup merge of #96971 - zhaixiaojuan:master, r=wesleywiser 2023-04-11 20:28:45 -07:00