…bc004bb6d1965a5f3f'

git-subtree-dir: compiler/rustc_codegen_gcc
git-subtree-mainline: ae90dcf
git-subtree-split: afae271

…t-codegen

…t-codegen

…t-codegen

* Implement basic support for inline assembly

* Disable LTO

We don't support it yet at all

* Handle `inout(reg) var` correctly

Turns out that `+` readwrite output registers cannot be tied with
input variables.

* Add limited support for llvm_asm!

* Handle CHANNEL correctly

* Add support for arbitrary explicit registers

* Handle symbols properly

* Add rudimentary asm tests

* Exclude llvm_asm! tests from tests runs

* Insert `__builtin_unreachable()` after diverging asm blocks

* Implement `black_box` as intrinsic

Responsibility of implementing the black box is now lies on backend

* Remove some TODOs

* Update to nightly-2021-09-17

* CI: don't fail on warnings

…t-codegen

* Correctly handle st(0) register in the clobbers list
* Gate the clobbers based on enabled target features

* Make define_global() return a RValue directly
* Return LValue in functions declaring a global variable
* Remove useless cast
* Fix bytes_in_context to use an array rvalue
* Remove global_names which is unused
* Make const_struct create a constant struct
* Correctly initialize global in static_addr_of_mut
* Fix global variable initialization
* Remove workaround for ARGV

* Cleanup fix for global initialization
* Remove linker script hack
* Use v0 symbol mangling
* Fix warnings

* Refactor test.sh script

* Fix mismatched types error

* Fix count trailing zeroes
* Fix pop count
* Fix bit reverse

…t-codegen

…t-codegen