[Info-vax] Userland programming languages on VMS.

[Andreas Gruhl]

Johnny Billquist schrieb am Montag, 31. Januar 2022 um 09:33:06 UTC+1:
> On 2022-01-31 01:43, Arne Vajhøj wrote: 
> > On 1/30/2022 7:19 PM, Simon Clubley wrote: 
> >> On 2022-01-29, Arne Vajhøj <ar... at vajhoej.dk> wrote: 
> >>> On 1/29/2022 1:53 AM, George Cornelius wrote: 
> >>>> 
> >>>> Works on Eisner. 
> >>>> 
> >>>> $ show sys/noproc 
> >>>> OpenVMS V8.4-2L2  on node EISNER   29-JAN-2022 [...] 
> >>>> 
> >>>> Here's the memory layout synopsis from a linker map: 
> >>>> 
> >>>> Virtual memory allocated:                         00010000 0005FFFF 
> >>>> 00050000 (327680. bytes, 640. pages) 
> >>>> 64-Bit Virtual memory allocated:                  00000000 00000000 
> >>>> 00000000 
> >>>>                                                     80000000 
> >>>> 80010000 00010000 (65536. bytes, 128. pages) 
> >>>> 
> >>>> The example, though, shows too small an allocation to escape 32 bit 
> >>>> address space. 
> >>> 
> >>> I consider 0000000080000000 to be 64 bit space. 
> >>> 
> >>> 0000000000000000 - 000000007FFFFFFF is P0 and P1 space 
> >>> FFFFFFFF80000000 - FFFFFFFFFFFFFFFF is S0 and S1 space 
> >>> 0000000080000000 and upward is P2 space 
> >>> 
> >> 
> >> I think George's point is that this specific address can be 
> >> represented in a 32-bit pointer. 
> > 
> > It can't. 
> > 
> > A 32 bit pointer with the value 80000000 will end up as 
> > FFFFFFFF80000000.
> Since when are pointers considered to be signed and need sign extension? 
> 
> Johnny