mirror of
https://gitlab.com/freepascal.org/fpc/source.git
synced 2025-06-01 11:42:43 +02:00
41fba0c4f7
instead of the frame pointer register:
1) we exactly know the offsets of the temps from the stack pointer
after pass 1 (based on the require parameter stack size for called
routines), while we don't know it for the frame pointer (it depends
on the number of saved registers)
2) temp offsets from the stack pointer are positive while those from
the frame pointer are negative, and we can directly encode much
bigger positive offsets in the instructions
o move the stack pointer register to a virtual register in
loadparentfpn, because many instructions cannot directly operate
on/with the stack pointer
o add the necessary register interference edges for the stack pointer
register
git-svn-id: trunk@29938 -
69 lines
2.0 KiB
ObjectPascal
69 lines
2.0 KiB
ObjectPascal
{
|
|
Copyright (c) 2002 by Florian Klaempfl
|
|
|
|
This unit contains the CPU specific part of tprocinfo
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
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. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
|
|
****************************************************************************
|
|
}
|
|
unit cpupi;
|
|
|
|
{$i fpcdefs.inc}
|
|
|
|
interface
|
|
|
|
uses
|
|
procinfo,
|
|
psub;
|
|
|
|
type
|
|
taarch64procinfo=class(tcgprocinfo)
|
|
constructor create(aparent: tprocinfo); override;
|
|
procedure set_first_temp_offset; override;
|
|
end;
|
|
|
|
implementation
|
|
|
|
uses
|
|
tgobj,
|
|
cpubase;
|
|
|
|
constructor taarch64procinfo.create(aparent: tprocinfo);
|
|
begin
|
|
inherited;
|
|
{ use the stack pointer as framepointer, because
|
|
1) we exactly know the offsets of the temps from the stack pointer
|
|
after pass 1 (based on the require parameter stack size for called
|
|
routines), while we don't know it for the frame pointer (it depends
|
|
on the number of saved registers)
|
|
2) temp offsets from the stack pointer are positive while those from
|
|
the frame pointer are negative, and we can directly encode much
|
|
bigger positive offsets in the instructions
|
|
}
|
|
framepointer:=NR_STACK_POINTER_REG;
|
|
end;
|
|
|
|
procedure taarch64procinfo.set_first_temp_offset;
|
|
begin
|
|
{ leave room for allocated parameters }
|
|
tg.setfirsttemp(align(maxpushedparasize,16));
|
|
end;
|
|
|
|
|
|
begin
|
|
cprocinfo:=taarch64procinfo;
|
|
end.
|