[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Lightning] Argument Management

From: Paolo Bonzini
Subject: Re: [Lightning] Argument Management
Date: Wed, 20 Feb 2008 07:50:58 +0100
User-agent: Thunderbird (Macintosh/20071031)

Sandro Magi wrote:
Under the "Argument Management" section, it states the following:

  You cannot pass parameters between subroutines using the six
general-purpose registers. This might work only when targeting
particular architectures.

Does this mean that I can't write a VM which performs interprocedural
register allocation using GNU Lightning? Or is this statement intended
to apply only when using the C call convention?

It's mostly because of the SPARC, which uses register windows. If you don't care about it, you can pass parameters using GPR.

The way I worked around it in GNU Smalltalk was to run the whole interpreter in "continuation-passing style". Which is, in fact, a different calling convention than the standard one.

I'm assuming this applies only to functions which use the the standard
jit_prolog. If I'm generating code using another calling convention
using JIT_R/V/FPR, then the above doesn't apply, correct?

With the SPARC caveat -- no, it does not apply.


reply via email to

[Prev in Thread] Current Thread [Next in Thread]