Add support for powerpc-unknown-linux-gnuspe

[glaubitz]

This PR adds support for the embedded PowerPC variant "e500". On Linux, this architecture is usually called "powerpcspe", it is a 32-bit PowerPC architecture. The main difference between normal 32-bit PowerPC and PowerPCSPE is the lack of Altivec instructions and the additional SPE instruction set.

This architecture is supported in Debian through an unofficial port.

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @cramertj (or someone else) soon.

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[glaubitz]

CC @jrtc27

[cramertj]

r? @alexcrichton (why do I keep getting assigned to these? XD)

[alexcrichton]

@bors: r+ rollup

[bors]

📌 Commit 9bbacca has been approved by alexcrichton

[bors]

🌲 The tree is currently closed for pull requests below priority 900, this pull request will be tested once the tree is reopened

[bors]

☔ The latest upstream changes (presumably #48531) made this pull request unmergeable. Please resolve the merge conflicts.

[glaubitz]

@alexcrichton Just rebased the PR, could you have another look?

[alexcrichton]

@bors: r+

[bors]

📌 Commit 7c84ba4 has been approved by alexcrichton

[skydig]

@alexcrichton
I use following command to build std for powerpc gnuspe,

cargo build -Z build-std --target=powerpc-unknown-linux-gnuspe

and run under target, crash is as following,

Program received signal SIGILL, Illegal instruction.
0x204f2610 in core::sync::atomic::atomic_compare_exchange::hdd78233f59efc1d2 ()
at /usr/share/rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/sync/atomic.rs:2643
2643 /usr/share/rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/sync/atomic.rs: No such file or directory.
in /usr/share/rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/sync/atomic.rs
(gdb) quit

please help

thanks

[glaubitz]

Please open a new issue for your problem.