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* fpc_mul_qword uses always the assembler implementation

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This commit is contained in:
florian 2004-05-10 20:58:20 +00:00
parent 39f5874341
commit 7f2606ed8a
1 changed files with 33 additions and 52 deletions
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85
rtl/i386/int64p.inc
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@ -174,64 +174,45 @@
function fpc_mul_qword(f1,f2 : qword;checkoverflow : longbool) : qword;[public,alias: 'FPC_MUL_QWORD']; {$ifdef hascompilerproc} compilerproc; {$endif}
var
_f1,bitpos : qword;
l : longint;
_f1 : qword;
r : qword;
begin
if not(checkoverflow) then
begin
{ the following piece of code is taken from the }
{ AMD Athlon Processor x86 Code Optimization manual }
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 [ 'eax','edx','ecx' ];
fpc_mul_qword:=r;
end
else
begin
fpc_mul_qword:=0;
bitpos:=1;
// store f1 for overflow checking
_f1:=f1;
for l:=0 to 63 do
begin
if (f2 and bitpos)<>0 then
fpc_mul_qword:=fpc_mul_qword+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 <> 0) and (f2 <>0) and
((_f1>fpc_mul_qword) or (f2>fpc_mul_qword)) then
HandleErrorFrame(215,get_frame);
end;
_f1:=f1;
{ the following piece of code is taken from the
AMD Athlon Processor x86 Code Optimization manual }
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 [ 'eax','edx','ecx' ];
fpc_mul_qword:=r;
{ if one of the operands is greater than the result an
overflow occurs }
if checkoverflow and (_f1<>0) and (f2<>0) and
((_f1>fpc_mul_qword) or (f2>fpc_mul_qword)) then
HandleErrorFrame(215,get_frame);
end;
{
$Log$
Revision 1.2 2003-12-23 23:09:43 peter
Revision 1.3 2004-05-10 20:58:20 florian
* fpc_mul_qword uses always the assembler implementation
Revision 1.2 2003/12/23 23:09:43 peter
* fix call to handleerror for regcall
Revision 1.1 2003/09/14 11:34:13 peter