HP 3000 Manuals HP 3000 Manuals
Switch to NM Sequence
Examples 4-3 through 4-8 are a series of routines, intended to illustrate
the partial recompilation migration level, using a CM--> NM switch.
In these examples the target procedure migrates to Native Mode while the
calling routine remains in Compatibility Mode.
A possible reason for moving the target procedure to Native Mode is that
it has a feature that is no longer available on MPE XL and an attractive
alternative exists in the NM environment. Example 4-3 is a Pascal/V
source with a procedure call to the PTAPE intrinsic (deleted on MPE XL).
Example 4-3. Pascal/V Program Calling Routine With Deleted Featur
PROGRAM XAMPL43(input,output);
TYPE
pac37 = packed array [1..37] of char;
logical = 0..65535;
shortint = -32768..32767;
VAR
fname1 : pac37;
fname2 : pac37;
filenum1 : shortint;
filenum2 : shortint;
foptions1 : logical;
foptions2 : logical;
aoptions1 : logical;
aoptions2 : logical;
recsize1 : shortint;
recsize2 : shortint;
dev1 : shortint;
dev2 : shortint;
function fopen : shortint; intrinsic;
procedure ptape (fnum1, fnum2 : shortint); external;
BEGIN
fname1 := '$STDIN ';
foptions1 := 0;
aoptions1 := 0;
recsize1 := 0;
dev1 := 0;
filenum1 := FOPEN(fname1, foptions1, aoptions1,
recsize1, dev1);
writeln('fopen ',fname,'ccode is ',ccode);
fname2 := 'XMPLA ';
foptions2 := 0;
aoptions2 := 0;
recsize2 := 0;
dev2 :=0;
filenum2 := FOPEN(fname2, foptions2, aoptions2,
recsize2, dev2);
writeln('fopen ',fname2,'ccode is ',ccode);
Example 4-3. Pascal/V Program, continued
PTAPE(filenum1,filenum2);
writeln('ptape result: ');
case ccode of
0 : writeln('CCE');
1 : writeln('CCG');
2 : writeln('CCL');
end;
END.
{end Example 4-3}
Example 4-4 is an SPL procedure incorporating the call to the PTAPE
intrinsic.
Example 4-4. SPL Procedure With Feature Deleted on MPE XL
$CONTROL USLINIT,SUBPROGRAM,SEGMENT=XAMPL43
BEGIN
EQUATE BASE = 10;
DEFINE D'MININT = -214748256D#;
EQUATE OFFSET = 48;
EQUATE PLACES = 9; << size of maxint, 32-bits >>
INTRINSIC FREAD, FWRITE;
PROCEDURE PTAPE(FILE1, FILE2);
VALUE FILE1, FILE2;
INTEGER FILE1, FILE2;
<< PTAPE replaces the deleted MPE/V intrinsic of the >>
<< same name. This routine transfers records from >>
<< FILE1 to FILE2. >>
BEGIN
INTEGER RECLEN, LEN;
LOGICAL ARRAY BUFFER(1:256);
RECLEN := 256;
DO
BEGIN
LEN := FREAD(FILE1, BUFFER, RECLEN);
IF = THEN FWRITE(FILE2, BUFFER, LEN, 0);
END
UNTIL <>;
END;
END.
{end Example 4-4}
To replace the deleted feature, you may want to write your own NM
procedure. Example 4-5 is an HP Pascal/XL procedure replacing the call
to the deleted PTAPE intrinsic with an MPE XL feature. This procedure
will replace the SPL procedure.
Example 4-5. Pascal/XL Procedure Replacing Deleted Feature
$standard_level 'ext_modcal'$
$subprogram$
PROGRAM XAMPL45 (input,output);
TYPE
pac256 = packed array [1..256] of char;
FUNCTION FREAD : SHORTINT; INTRINSIC;
PROCEDURE FWRITE; INTRINSIC;
PROCEDURE PTAPE(FILE1, FILE2 : integer);
{ PTAPE replaces the deleted MPE/V intrinsic of the }
{ same name. This routine transfers records from }
{ FILE1 to FILE2. }
VAR
reclen : shortint;
len : shortint;
buffer : pac256;
BEGIN
reclen := 256;
repeat
begin
len := FREAD(file1, buffer, reclen);
if ccode = 2 then FWRITE(file2, buffer, len, 0);
end
until (ccode <> 2);
END;
begin
end.
{end Example 4-5}
It is advisable to test one thing at a time. You can test the NM
replacement procedure separately from a Switch stub or in-line Switch
that calls the appropriate intrinsic to invoke the target. Example 4-6
is an NM driver to test the HP Pascal/XL procedure.
Example 4-6. NM Driver
$standard_level 'ext_modcal'$
PROGRAM XAMPL46(input,output);
TYPE
pac37 = packed array [1..37] of char;
logical = 0..65535;
VAR
fname1 : pac37;
fname2 : pac37;
filenum1 : shortint;
filenum2 : shortint;
foptions1 : logical;
foptions2 : logical;
aoptions1 : logical;
aoptions2 : logical;
recsize1 : shortint;
recsize2 : shortint;
dev1 : shortint;
dev2 : shortint;
FUNCTION FOPEN : SHORTINT; INTRINSIC;
PROCEDURE ptape (filenum1, filenum2 : shortint); external;
BEGIN
fname1 := '$STDIN ';
foptions1 := 0;
aoptions1 := 0;
recsize1 := 0;
dev1 := 0;
filenum1 := FOPEN(fname1, foptions1, aoptions1,
recsize1, dev1);
writeln('fopen ',fname1,'ccode is ',ccode);
fname2 := 'PTAPE ';
foptions2 := 0;
aoptions2 := 0;
recsize2 := 0;
dev2 := 0;
filenum2 := FOPEN(fname2, foptions2, aoptions2,
recsize2, dev2);
writeln('fopen ',fname2,'ccode is ',ccode);
Example 4-6. NM Driver, continued
ptape(filenum1,filenum2);
writeln('ptape result: ');
case ccode of
0 : writeln('CCE');
1 : writeln('CCG');
2 : writeln('CCL');
end;
END.
{end Example 4-6}
As it stands, the HP Pascal/XL procedure represents an unresolvable
external reference to the CM routine that must call it. Again, you can
use either a Switch stub or an in-line Switch to enable the CM caller to
access the NM target. Example 4-7 is a Pascal/V Switch stub enabling
access to the HP Pascal/XL procedure.
Example 4-7. Pascal/V Switch Stub
$standard_level 'HP3000'$
PROGRAM XAMPL47(input, output);
TYPE
shortint = -32768..32767;
FUNCTION HPSWTONMNAME : integer; intrinsic;
PROCEDURE ptape(file1, file2 : shortint);
TYPE
pac256 = packed array [1..256] of char;
pac16 = packed array [1..16] of char;
shr_ary32 = packed array [1..32] of shortint;
VAR
proc_name : pac16;
proc_len : shortint;
lib_name : pac16;
lib_len : shortint;
nparms : shortint;
arglist : shr_ary32;
argdesc : shr_ary32;
fct_type : shortint;
rtn_st : integer;
Example 4-7. Pascal/V Switch Stub, continued
BEGIN
proc_name := 'PTAPE ';
proc_len := 5;
lib_name := 'SL ';
lib_len := 2;
nparms := 2;
arglist[1] := file1;
arglist[2] := file2;
argdesc[1] := 02; { 16-bit value }
argdesc[2] := 02; { 16-bit value }
fct_type := 0; {not a function }
rtn_st := HPSWTONMNAME(proc_name, proc_len, lib_name,
lib_len, nparms, arglist,
argdesc, fct_type);
END;
BEGIN
END.
{end Example 4-7}
To compile the Switch stub in Example 4-7, use the :PASCAL command. For
complete information, refer to the MPE XL Commands Reference Manual
(32650-90003).
On the CM side, you must use the MPE Segmenter to put the stub into the
CM SL in place of the SPL target procedure. Example 4-8 illustrates an
MPE Segmenter session to replace the SPL procedure with the Switch stub
in Example 4-7.
Example 4-8. Segmenter Session
:SEGMENTER
HP32050A.02.00 SEGMENTER/3000 (C) HEWLETT-PACKARD CO 1985
-SL SL
-LISTSL
SL FILE SL.SWITCH.EXAMPLE
SEGMENT 0 SWCMLIB LENGTH 706
ENTRY POINTS CHECK CAL STT ADR
PTAPE 3 C 1 13
EXTERNALS CHECK STT SEG
FWRITE 0 13 ?
FREAD 0 12 ?
USED 4600(23.0) AVAILABLE 2334200(11565.0)
-PURGESL PTAPE
-USL $OLDPASS
-ADDSL PTAPE
-EXIT
END OF SUBSYSTEM
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