clarification question

clarification question

[Péntek Imre]

Hi,

https://gcc.gnu.org/backends.html

by "Architecture does not have a single condition code register" do you 
mean it has none or do you mean it has multiple?

Thank you in advance for the clarification.
-- 
With regards: Imre PÉNTEK
Üdvözlettel: PÉNTEK Imre
E-mail: pentek.imre@gmail.com

Re: clarification question

[Marc Glisse]

On Sat, 22 Oct 2022, Péntek Imre via Gcc wrote:

> https://gcc.gnu.org/backends.html
>
> by "Architecture does not have a single condition code register" do you mean 
> it has none or do you mean it has multiple?

Either.

If you look at the examples below, there is a C for riscv, which has 0, 
and one for sparc, which has several.

-- 
Marc Glisse

Re: clarification question

[Paul Koning]

> On Oct 22, 2022, at 2:38 PM, Marc Glisse via Gcc <gcc@gcc.gnu.org> wrote:
> 
> On Sat, 22 Oct 2022, Péntek Imre via Gcc wrote:
> 
>> https://gcc.gnu.org/backends.html
>> 
>> by "Architecture does not have a single condition code register" do you mean it has none or do you mean it has multiple?
> 
> Either.
> 
> If you look at the examples below, there is a C for riscv, which has 0, and one for sparc, which has several.

Also pdp11, which has two: one for floating point, one for integers, and conditional branches act only on the integer CC register.  So the MD has to describe a "move float CC to integer CC" operation.

GCC supports all these strange things quite nicely -- this is one of several things that the newer CCmode machinery does well and the old "cc0" stuff doesn't.

	paul