[fpc-pascal] intel asm and fpc-1.9.8

[Jan Je/lowicki]

Hello,

I have dozens of blas-like assembler procedures. They have been 
written about 10 years ago and I still use them in both virtualpascal 
and free pascal programs.

Today I tried new fpc 1.9.8. Output generated from fpc 1.9.8 code 
seems errorenous. The isolated example given below tries to fill an 
array of float with contstant value. Gdb (5.3) gives no reasonable 
support, although for 1.0.10 code it does.

program atest;
type  dvector = array[1..10] of double;
const  dflsize = sizeof(double);
var   x: dvector;   i: integer;   a: double;
  {$ifdef VirtualPascal} 
  {$SAVES EBX,ESI,EDI} {$USES EAX,ECX,EDX}  {$endif}
  procedure vecfill(const dim0,dim1: integer; 
                    var r: dVector; c: extended); assembler;
  asm
    MOV     EAX,dim1;
    SUB     EAX,dim0;
    MOV     EDX,dflsize
    MUL     EDX

    FLD     TByte ptr [c]

    push    eax
    mov     eax,dim0
    dec     eax
    mov     edx,dflsize
    mul     edx
    MOV     EDX, r
    ADD     EDX,EAX
    pop     eax
    JMP     @@2
  @@1:
    FST     QWord ptr [EDX + EAX]
    SUB     EAX,dflsize
  @@2:
    CMP     EAX,0
    JGE     @@1

    FSTP    ST(0)
  end; {asmvecfill}
  
begin
  a := 123.45;  
  fillchar(x, sizeof(x),0);
  vecfill(2, 5, x, a);
  for i := 1 to 6 do
    writeln(x[i]);
end.

Here is output by fpc 1.9.8:

 0.000000000000000E+000
 0.000000000000000E+000
 0.000000000000000E+000
 0.000000000000000E+000

(or access violation when arrays allocated dynamically).
Output by fpc 1.0.10 and vp 2.1 which is one I expect:

 1.234500000000000E+002
 1.234500000000000E+002
 1.234500000000000E+002
 1.234500000000000E+002

Any ideas?


                                       Jan Jelowicki
                                       jasj at ozi.ar.wroc.pl
                         
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Wroclaw University of Agriculture    Akademia Rolnicza we Wroclawiu
Department of Mathematics            Katedra Matematyki
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