fpc/rtl/inc/int64.inc

490 lines
12 KiB
PHP

{
$Id$
This file is part of the Free Pascal run time library.
Copyright (c) 1999-2000 by the Free Pascal development team
This file contains some helper routines for int64 and qword
See the file COPYING.FPC, included in this distribution,
for details about the copyright.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
**********************************************************************}
{$Q- no overflow checking }
{$R- no range checking }
type
tqwordrec = packed record
low : dword;
high : dword;
end;
function count_leading_zeros(q : qword) : longint;
var
r,i : longint;
begin
r:=0;
for i:=0 to 31 do
begin
if (tqwordrec(q).high and ($80000000 shr i))<>0 then
begin
count_leading_zeros:=r;
exit;
end;
inc(r);
end;
for i:=0 to 31 do
begin
if (tqwordrec(q).low and ($80000000 shr i))<>0 then
begin
count_leading_zeros:=r;
exit;
end;
inc(r);
end;
count_leading_zeros:=r;
end;
function divqword(n,z : qword) : qword;[public,alias: 'FPC_DIV_QWORD'];
var
shift,lzz,lzn : longint;
{ one : qword; }
begin
divqword:=0;
if n=0 then
HandleErrorFrame(200,get_frame);
lzz:=count_leading_zeros(z);
lzn:=count_leading_zeros(n);
{ if the denominator contains less zeros }
{ then the numerator }
{ the d is greater than the n }
if lzn<lzz then
exit;
shift:=lzn-lzz;
n:=n shl shift;
repeat
if z>=n then
begin
z:=z-n;
divqword:=divqword+(qword(1) shl shift);
end;
dec(shift);
n:=n shr 1;
until shift<0;
end;
function modqword(n,z : qword) : qword;[public,alias: 'FPC_MOD_QWORD'];
var
shift,lzz,lzn : longint;
begin
modqword:=0;
if n=0 then
HandleErrorFrame(200,get_frame);
lzz:=count_leading_zeros(z);
lzn:=count_leading_zeros(n);
{ if the denominator contains less zeros }
{ then the numerator }
{ the d is greater than the n }
if lzn<lzz then
begin
modqword:=z;
exit;
end;
shift:=lzn-lzz;
n:=n shl shift;
repeat
if z>=n then
z:=z-n;
dec(shift);
n:=n shr 1;
until shift<0;
modqword:=z;
end;
function divint64(n,z : int64) : int64;[public,alias: 'FPC_DIV_INT64'];
var
sign : boolean;
q1,q2 : qword;
c : comp;
begin
if n=0 then
HandleErrorFrame(200,get_frame);
{ can the fpu do the work? }
if fpuint64 then
begin
// the c:=comp(...) is necessary to shut up the compiler
c:=comp(comp(z)/comp(n));
divint64:=qword(c);
end
else
begin
sign:=false;
if z<0 then
begin
sign:=not(sign);
q1:=qword(-z);
end
else
q1:=z;
if n<0 then
begin
sign:=not(sign);
q2:=qword(-n);
end
else
q2:=n;
{ the div is coded by the compiler as call to divqword }
if sign then
divint64:=-(q1 div q2)
else
divint64:=q1 div q2;
end;
end;
{ multiplies two qwords
the longbool for checkoverflow avoids a misaligned stack
}
function mulqword(f1,f2 : qword;checkoverflow : longbool) : qword;[public,alias: 'FPC_MUL_QWORD'];
var
_f1,bitpos : qword;
l : longint;
{$ifdef i386}
r : qword;
{$endif i386}
begin
{$ifdef i386}
if not(checkoverflow) then
begin
asm
movl f1+4,%edx
movl f2+4,%ecx
orl %ecx,%edx
movl f2,%edx
movl f1,%eax
jnz .Lqwordmultwomul
mull %edx
jmp .Lqwordmulready
.Lqwordmultwomul:
imul f1+4,%edx
imul %eax,%ecx
addl %edx,%ecx
mull f2
add %ecx,%edx
.Lqwordmulready:
movl %eax,r
movl %edx,r+4
end;
mulqword:=r;
end
else
{$endif i386}
begin
mulqword:=0;
bitpos:=1;
// store f1 for overflow checking
_f1:=f1;
for l:=0 to 63 do
begin
if (f2 and bitpos)<>0 then
mulqword:=mulqword+f1;
f1:=f1 shl 1;
bitpos:=bitpos shl 1;
end;
{ if one of the operands is greater than the result an }
{ overflow occurs }
if checkoverflow and ((_f1>mulqword) or (f2>mulqword)) then
HandleErrorFrame(215,get_frame);
end;
end;
{ multiplies two int64 ....
fpuint64 = false:
... using the the qword multiplication
fpuint64 = true:
... using the comp multiplication
the longbool for checkoverflow avoids a misaligned stack
}
function mulint64(f1,f2 : int64;checkoverflow : longbool) : int64;[public,alias: 'FPC_MUL_INT64'];
var
sign : boolean;
q1,q2,q3 : qword;
c : comp;
begin
{ can the fpu do the work ? }
if fpuint64 and not(checkoverflow) then
begin
// the c:=comp(...) is necessary to shut up the compiler
c:=comp(comp(f1)*comp(f2));
mulint64:=int64(c);
end
else
begin
sign:=false;
if f1<0 then
begin
sign:=not(sign);
q1:=qword(-f1);
end
else
q1:=f1;
if f2<0 then
begin
sign:=not(sign);
q2:=qword(-f2);
end
else
q2:=f2;
{ the q1*q2 is coded as call to mulqword }
q3:=q1*q2;
if checkoverflow and ((q1>q3) or (q2>q3) or
{ the bit 63 can be only set if we have $80000000 00000000 }
{ and sign is true }
((tqwordrec(q3).high and $80000000)<>0) and
((q3<>(qword(1) shl 63)) or not(sign))
) then
HandleErrorFrame(215,get_frame);
if sign then
mulint64:=-q3
else
mulint64:=q3;
end;
end;
procedure qword_str(value : qword;var s : string);
var
hs : string;
begin
hs:='';
repeat
hs:=chr(longint(value mod 10)+48)+hs;
value:=value div 10;
until value=0;
s:=hs;
end;
procedure int64_str(value : int64;var s : string);
var
hs : string;
q : qword;
begin
if value<0 then
begin
q:=qword(-value);
qword_str(q,hs);
s:='-'+hs;
end
else
qword_str(qword(value),s);
end;
procedure int_str_qword(v : qword;len : longint;var s : shortstring);[public,alias:'FPC_SHORTSTR_QWORD'];
begin
qword_str(v,s);
if length(s)<len then
s:=space(len-length(s))+s;
end;
procedure int_str_int64(v : int64;len : longint;var s : shortstring);[public,alias:'FPC_SHORTSTR_INT64'];
begin
int64_str(v,s);
if length(s)<len then
s:=space(len-length(s))+s;
end;
procedure int_str_qword(v : qword;len : longint;var s : ansistring);[public,alias:'FPC_ANSISTR_QWORD'];
var
ss : shortstring;
begin
int_str_qword(v,len,ss);
s:=ss;
end;
procedure int_str_int64(v : int64;len : longint;var s : ansistring);[public,alias:'FPC_ANSISTR_INT64'];
var
ss : shortstring;
begin
int_str_int64(v,len,ss);
s:=ss;
end;
Function ValInt64(DestSize: longint; Const S: ShortString; var Code: ValSInt): Int64; [public, alias:'FPC_VAL_INT64_SHORTSTR'];
var
u, temp, prev : Int64;
base : byte;
negative : boolean;
begin
ValInt64 := 0;
Temp:=0;
Code:=InitVal(s,negative,base);
if Code>length(s) then
exit;
if negative and (s='-9223372036854775808') then
begin
Code:=0;
ValInt64:=Int64($80000000) shl 32;
exit;
end;
while Code<=Length(s) do
begin
case s[Code] of
'0'..'9' : u:=Ord(S[Code])-Ord('0');
'A'..'F' : u:=Ord(S[Code])-(Ord('A')-10);
'a'..'f' : u:=Ord(S[Code])-(Ord('a')-10);
else
u:=16;
end;
Prev:=Temp;
Temp:=Temp*Int64(base);
if (Temp<prev) Then
Begin
ValInt64:=0;
Exit
End;
prev:=temp;
Temp:=Temp+u;
if prev>temp then
begin
ValInt64:=0;
exit;
end;
inc(code);
end;
code:=0;
ValInt64:=Temp;
If Negative Then
ValInt64:=-ValInt64;
end;
Function ValQWord(Const S: ShortString; var Code: ValSInt): QWord; [public, alias:'FPC_VAL_QWORD_SHORTSTR'];
var
u, prev: QWord;
base : byte;
negative : boolean;
begin
ValQWord:=0;
Code:=InitVal(s,negative,base);
If Negative or (Code>length(s)) Then
Exit;
while Code<=Length(s) do
begin
case s[Code] of
'0'..'9' : u:=Ord(S[Code])-Ord('0');
'A'..'F' : u:=Ord(S[Code])-(Ord('A')-10);
'a'..'f' : u:=Ord(S[Code])-(Ord('a')-10);
else
u:=16;
end;
prev := ValQWord;
ValQWord:=ValQWord*QWord(base);
If (prev>ValQWord) or (u>base) Then
Begin
ValQWord := 0;
Exit
End;
prev:=ValQWord;
ValQWord:=ValQWord+u;
if prev>ValQWord then
begin
ValQWord:=0;
exit;
end;
inc(code);
end;
code := 0;
end;
{
$Log$
Revision 1.17 2000-01-27 15:43:02 florian
* improved qword*qword code, if no overflow checking is done
Revision 1.16 2000/01/23 12:27:39 florian
* int64/int64 and int64*int64 is now done by the fpu if possible
Revision 1.15 2000/01/23 12:22:37 florian
* reading of 64 bit type implemented
Revision 1.14 2000/01/07 16:41:34 daniel
* copyright 2000
Revision 1.13 1999/07/05 20:04:23 peter
* removed temp defines
Revision 1.12 1999/07/04 16:34:45 florian
+ str routines added
Revision 1.11 1999/07/02 17:01:29 florian
* multiplication overflow checking fixed
Revision 1.10 1999/07/01 15:39:50 florian
+ qword/int64 type released
Revision 1.9 1999/06/30 22:12:40 florian
* qword div/mod fixed
+ int64 mod/div/* fully implemented
* int_str(qword) fixed
+ dummies for read/write(qword)
Revision 1.8 1999/06/28 22:25:25 florian
* fixed qword division
Revision 1.7 1999/06/25 12:24:44 pierre
* qword one was wrong !
Revision 1.6 1999/06/02 10:13:16 florian
* multiplication fixed
Revision 1.5 1999/05/25 20:36:41 florian
* some bugs removed
Revision 1.4 1999/05/24 08:43:46 florian
* fixed a couple of syntax errors
Revision 1.3 1999/05/23 20:27:27 florian
+ routines for qword div and mod
Revision 1.2 1999/01/06 12:25:03 florian
* naming for str(...) routines inserted
* don't know what in int64 changed
Revision 1.1 1998/12/12 12:15:41 florian
+ first implementation
}