help about new porting (.h file)

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On Thu, 3 Apr 2003, Gabriele Caracausi wrote:

> Hi all, 
> 
> I'm working on GCC porting of PIC18C and I've a couple of questions. 
> 
> I'm studing ip2k porting because this is the most similar to PIC18C. 
> 
> I report from official "Using and Porting GCC" (p. 445), "Pmode is defined 
> as an alias for the machine mode for pointers. On most machines, define this 
> to be the integer mode corresponding to the width of a hardware pointer; 
> SImode on 32 bit machine or DImode on 64-bit machines. [...] The width of 
> Pmode must be at least as large as the value of POINTER_SIZE. If it is not 
> equal you must define the macro POINTERS_EXTEND_UNSIGNED to specify how 
> pointers are extended to Pmode." 
> 
> In the IP2k porting (ip2k.h):
> * POINTER_SIZE is setted to 16 bit
> * Pmode is setted to HImode
> * INT_TYPE_SIZE is setted to 16 bit so HImode should be 8 bit.

from "rtl.texi" line 890 of 3502:

@findex HImode
@item HImode
``Half-Integer'' mode represents a two-byte integer.

HImode is always 16 bits.

Toshi