Trait impls are still insta-stable yeah...?

…ed indirectly

Structs being passed indirectly is suprpising and have a high chance not to work as the device and host usually do not share memory.

…an-DPC

Clarify that `Cow::into_owned` returns owned data

Two sections of the `Cow::into_owned` docs imply that `into_owned` returns a `Cow`. Clarify that it returns the underlying owned object, either cloned or extracted from the `Cow`.

… r=nagisa

Fix codegen bug in "ptx-kernel" abi related to arg passing

I found a codegen bug in the nvptx abi related to that args are passed as ptrs ([see comment](rust-lang#38788 (comment))), this is not as specified in the [ptx-interoperability doc](https://docs.nvidia.com/cuda/ptx-writers-guide-to-interoperability/) or how C/C++ does it. It will also almost always fail in practice since device/host uses different memory spaces for most hardware.

This PR fixes the bug and add tests for passing structs to ptx kernels.

I observed that all nvptx assembly tests had been marked as [ignore a long time ago](rust-lang#59752 (comment)). I'm not sure if the new one should be marked as ignore, it passed on my computer but it might fail if ptx-linker is missing on the server? I guess this is outside scope for this PR and should be looked at in a different issue/PR.

I only fixed the nvptx64-nvidia-cuda target and not the potential code paths for the non-existing 32bit target. Even though 32bit nvptx is not a supported target there are still some code under the hood supporting codegen for 32 bit ptx. I was advised to create an MCP to find out if this code should be removed or updated.

Perhaps `@RDambrosio016` would have interest in taking a quick look at this.

Implement Default for AssertUnwindSafe

Trait impls are still insta-stable yeah...?

Switch JS code to ES6

Considering it's already quite big, I'll do the remaining files in another PR.

Part of rust-lang#93058.

r? `@notriddle`

…t, r=oli-obk

Suggest calling method on nested field when struct is missing method

Similar to the suggestion to change `x.field` to `x.nested.field`, implement a similar suggestion for when `x.method()` should be replaced with `x.nested.method()`.

simplify `describe_field` func in borrowck's diagnostics part

This PR simplify the `describe_field` func in borrowck's diagnostics part, besides fix the FIXME in it.

…an-DPC

Correct documentation for `Rvalue::ShallowInitBox`

As a part of the big MIR docs PR, I had added a comment indicating that `Rvalue::ShallowInitBox` is disallowed after drop elaboration, but this is not true (no idea why I thought it was). Codegen has support for it, and trying to enforce this rule in the validator causes compiling core to ICE on the very first `box` statement.

That being said, this `Rvalue` probably *should* be banned after drop elaboration - it doesn't seem like it's still useful for much. However, I do not have time right now to actually go investigate how difficult a change that is to make, so in the meantime fixing the docs to reflect the current situation seems like the right step.

r? rust-lang/mir-opt

Remove references to git.io

The git.io service is shutting down soon (see https://github.blog/changelog/2022-04-25-git-io-deprecation/). This removes the references of those short links with the actual destination.