This may be better posted elsewhere but I thought I'd start here.
Here's the code running on a model 2828, hopefully it formats OK. This is just
a very basic test and not intended for production, just to try and experiment
with some new instructions.
BASR 12,0
USING *,12
open (sysprint,OUTPUT) open the dump file
snap dcb=sysprint,id=1, +
PDATA=(REGS,PSW)
lhi 7,256
llihf 8,256
sr 9,9
lhh 9,2
snap dcb=sysprint,id=2, +
PDATA=(REGS,PSW)
close sysprint
BR 14 return
drop 12
SYSPRINT dcb ddname=SYSPRINT, +
dsorg=PS,recfm=VBA,macrf=(W),blksize=1632,lrecl=125
The question is: why does the LHH never get executed? I tried using
MACHINE(ZS-6) but it still somehow goes from the SR straight to the SNAP. I
was expecting an operation exception if the opcode was invalid, or an access
exception if I didn't have addressability to the second operand. I even
single-stepped with Xpediter, which stepped right past the LHH as if it wasn't
there.
The SNAPs before and after show registers 7 and 8 as expected, but not 9 which
remains all zeroes. Obviously I've failed to understand something very basic.
Here's the snap after the LHH
64-BIT GPR VALUES
0-3 00000000 00000048 00000000 80007044 00000000 00000040
00000000 009D3D6C
4-7 00000000 009D3D48 00000000 009F8588 00000000 009BCFC8
00000000 00000100
8-11 00000100 00000000 00000000 00000000 00000000 00000000
00000000 00000000
12-15 00000000 00007002 00000000 00006008 00000000 80FD76C0
00000000 00000000
Would love to know why the LHH isn't working as expected. My reading of POps
leads me to think that R9 should be 00000002 00000000 but I must be reading it
wrong.
I was trying to find which document says which facilities are on which machine,
but the POps wasn't really helpful: although it describes the facilities in
detail it is not clear which models have which facility, in particular which
have the "high-word facility" that provides LHH and its ilk.
Thanks in advance for any insight you can offer.
best regards,
Peter
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