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Cc: GCC List <gcc@gcc.gnu.org>
From: Syd Polk <spolk@apple.com>
Subject: Re: Help restricting args of an intrinsic function
Date: Sat, 31 Jan 2004 01:07:00 -0000
To: Diego Novillo <dnovillo@redhat.com>
X-SW-Source: 2004-01/txt/msg02299.txt.bz2


On Jan 30, 2004, at 4:54 PM, Diego Novillo wrote:

> On Fri, 2004-01-30 at 19:46, Syd Polk wrote:
>
>> How can I safely:
>> 	- Determine if a value is really a compile-time constant?
>> 	- Get the value of that constant?
>>
> If you could wait a little while until tree-ssa is merged in mainline,
> this would be relatively simple to implement inside the tree 
> optimizers.
>
> So, if the compiler cannot assert that the arguments are compile-time
> constants, you want to emit an error?

Not only that, but compile-time constants in a certain range.

__builtin_prefetch does something similar, but only supports actual 
integers in the source code; it has the same characteristics as my 
original implementation.

>
>
> Diego.
>
>
Syd Polk
Apple Computer
Technology EPM, Mac OS X Development Tools
+1 408 974-0577