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Re: ptx preliminary rtl patches [3/4]


On 09/11/2014 06:34 PM, Steven Bosscher wrote:
On Thu, Sep 11, 2014 at 6:19 PM, Bernd Schmidt wrote:
What do you expect that function to do different? It returns the correct
value.


No different. Just that if you want to check whether DECL is a global
variable then we have a predicate for it. So why use TREE_STATIC
instead?

In other words: Just trying to make/keep certain checks consistent. (A
hopeless cause, but a noble one... ;-)


You're talking about a different patch here. This one is about
num_sign_bit_copies.


Ah. *sigh* can't even keep two patches in my mind at any one time.

The point about num_sign_bit_copies is that it doesn't really return
the correct value IMHO, if there isn't really a correct value to speak
of: What is the sign of TRUE or FALSE, the only two values a BImode
value can take?

A 1-bit precision integer can have value 0 or -1 and in that case
num_sign_bit_copies should be 0. But for a BImode value, it seems to
me that asking for the sign bit or sign bit copies is just wrong.

I strongly disagree. It's the same as for any other integer - there's one sign bit, and since there aren't any other bits, the number of sign bit copies is always exactly 1.


Bernd



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