Stream: git-cranelift

Topic: cranelift / Issue #455 Use callee-saved registers across ...

GitHub (Feb 28 2020 at 23:24):

alexcrichton transferred Issue #455:

Currently, cranelift spills all registers across calls, without regard to whether they're callee-saved.

However the nice thing about callee-saved registers is that they're saved across calls ;-), and Cranelift indeed supports the callee side of this.

At a high level, the steps here are:

• Generalize x86's callee_saved_gprs into callee_saved_regs and make it not specific to GPRs (this appears needed for saving XMM registers on windows_fastcall too).
• Refactor this callee_saved_regs from being a private function to being a function in the TargetIsa trait, so that we can access the callee_saved_gprs from other places in the code.
• Make the code mentioned above in spilling.rs consult the TargetIsa's callee_saved_regs set and skip spilling registers in the callee-saved set.

Last updated: Oct 23 2024 at 20:03 UTC