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+ new, much faster do_set_range based on the PowerPC version (which

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will be committed tomorrow)
This commit is contained in:
Jonas Maebe 2000-09-21 16:09:19 +00:00
parent 478ad23438
commit 33ee934d6e
1 changed files with 42 additions and 19 deletions
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61
rtl/i386/set.inc
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@ -92,27 +92,46 @@ end;
procedure do_set_range(p : pointer;l,h : byte);assembler;[public,alias:'FPC_SET_SET_RANGE'];
{
bad implementation, but it's very seldom used
adds the range [l..h] to the set pointed to by p
}
asm
pushl %eax
movl p,%edi
xorl %eax,%eax
xorl %ecx,%ecx
movb h,%al
movb l,%cl
.LSET_SET_RANGE_LOOP:
cmpl %ecx,%eax
jl .LSET_SET_RANGE_EXIT
movl %eax,%ebx
movl %eax,%edx
andl $0xf8,%ebx
andl $7,%edx
shrl $3,%ebx
btsl %edx,(%edi,%ebx)
dec %eax
jmp .LSET_SET_RANGE_LOOP
.LSET_SET_RANGE_EXIT:
movzbl l,%eax // lowest bit to be set in eax
movzbl h,%ebx // highest in ebx
cmpl %eax,%ebx
jb .Lset_range_done
movl p,%edi // set address in edi
movl %eax,%ecx // lowest also in ecx
shrl $3,%eax // divide by 8 to get starting and ending byte
shrl $3,%ebx // address
andb $31,%cl // low five bits of lo determine start of bit mask
movl $0x0ffffffff,%edx // edx = bitmask to be inserted
andl $0x0fffffffc,%eax // clear two lowest bits to get start/end longint
andl $0x0fffffffc,%ebx // address * 4
shll %cl,%edx // shift bitmask to clear bits below lo
addl %eax,%edi // go to starting pos in set
subl %eax,%ebx // are bit lo and hi in the same longint?
jz .Lset_range_hi // yes, keep current mask and adjust for hi bit
orl %edx,(%edi) // no, store current mask
movl $0x0ffffffff,%edx // new mask
addl $4,%edi // next longint of set
subl $4,%ebx // bit hi in this longint?
jz .Lset_range_hi // yes, keep full mask and adjust for hi bit
.Lset_range_loop:
movl %edx,(%edi) // no, fill longints in between with full mask
addl $4,%edi
subl $4,%ebx
jnz .Lset_range_loop
.Lset_range_hi:
movb h,%cl
movl %edx,%ebx // save current bitmask
andb $31,%cl
subb $31,%cl // cl := (31 - (hi and 31)) = shift count to
negb %cl // adjust bitmask for hi bit
shrl %cl,%edx // shift bitmask to clear bits higher than hi
andl %edx,%ebx // combine both bitmasks
orl %ebx,(%edi) // store to set
.Lset_range_done:
popl %eax
end;
@ -428,7 +447,11 @@ end;
{
$Log$
Revision 1.2 2000-07-13 11:33:41 michael
Revision 1.3 2000-09-21 16:09:19 jonas
+ new, much faster do_set_range based on the PowerPC version (which
will be committed tomorrow)
Revision 1.2 2000/07/13 11:33:41 michael
+ removed logs
}