On 64-bit this reduces the size of `Expr_` from 144 to 64 bytes, and
reduces the size of `Expr` from 176 to 96 bytes.

… node id

Most of the Rust community agrees that the vec! macro is more clear when
called using square brackets [] instead of regular brackets (). Most of
these ocurrences are from before macros allowed using different types of
brackets.

These are all legacies from before the clearer vec![] was possible to
write. They are now all gone. This would be a perfect time to write a
lint for ocurrences of vec!().

Sadly it looks like pretty printing still wants vec![]s to be vec!()s :(

This is something that should be fixed at another time.

Shrink Expr_::ExprInlineAsm.

On 64-bit this reduces the size of `Expr_` from 144 to 64 bytes, and
reduces the size of `Expr` from 176 to 96 bytes.

For the workload in rust-lang#36799 this reduces the RSS for the "lowering ast -> hir" phase and all subsequent phases by 50 MiB, which reduces the peak RSS for that workload by about 1%. Not huge, but it's a very easy improvement.

r? @eddyb

…ackets

Fix ICE when attempting to print closure generics

Fixes rust-lang#36622.

r? @eddyb or @arielb1

save-analysis: change imports to carry a ref id rather than their own…

… node id

To make jump to def for imports work

r? @eddyb

Do not clone Mir unnecessarily

r? @eddyb

…xcrichton

Replace all uses of SHA-256 with BLAKE2b.

Removes the SHA-256 implementation and replaces all uses of it with BLAKE2b, which we already use for debuginfo type guids and incremental compilation hashes. It doesn't make much sense to have two different cryptographic hash implementations in the compiler and Blake has a few advantages over SHA-2 (computationally less expensive, hashes of up to 512 bits).

Most of the Rust community agrees that the vec! macro is more clear when
called using square brackets [] instead of regular brackets (). Most of
these ocurrences are from before macros allowed using different types of
brackets.

…per-vec-brackets