fpc/compiler/ncgset.pas
2005-01-04 20:14:40 +00:00

935 lines
36 KiB
ObjectPascal

{
$Id$
Copyright (c) 1998-2002 by Florian Klaempfl and Carl Eric Codere
Generate generic assembler for in set/case labels
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 ncgset;
{$i fpcdefs.inc}
interface
uses
globtype,globals,
node,nset,cpubase,cgbase,cgobj,aasmbase,aasmtai;
type
tcgsetelementnode = class(tsetelementnode)
procedure pass_2;override;
end;
tcginnode = class(tinnode)
procedure pass_2;override;
protected
{# Routine to test bitnumber in bitnumber register on value
in value register. The __result register should be set
to one if the bit is set, otherwise __result register
should be set to zero.
Should be overriden on processors which have specific
instructions to do bit tests.
}
procedure emit_bit_test_reg_reg(list : taasmoutput;
bitsize: tcgsize; bitnumber,value : tregister;
ressize: tcgsize; res :tregister);virtual;
end;
tcgcasenode = class(tcasenode)
{
Emits the case node statement. Contrary to the intel
80x86 version, this version does not emit jump tables,
because of portability problems.
}
procedure pass_2;override;
protected
with_sign : boolean;
opsize : tcgsize;
jmp_gt,jmp_lt,jmp_le : topcmp;
{ register with case expression }
hregister,hregister2 : tregister;
endlabel,elselabel : tasmlabel;
{ true, if we can omit the range check of the jump table }
jumptable_no_range : boolean;
{ has the implementation jumptable support }
min_label : tconstexprint;
function blocklabel(id:longint):tasmlabel;
procedure optimizevalues(var max_linear_list:aint;var max_dist:aword);virtual;
function has_jumptable : boolean;virtual;
procedure genjumptable(hp : pcaselabel;min_,max_ : aint); virtual;
procedure genlinearlist(hp : pcaselabel); virtual;
procedure genlinearcmplist(hp : pcaselabel); virtual;
end;
implementation
uses
systems,
verbose,
symconst,symdef,defutil,
paramgr,
pass_2,tgobj,
nbas,ncon,nflw,
ncgutil,regvars,
cgutils;
{*****************************************************************************
TCGSETELEMENTNODE
*****************************************************************************}
procedure tcgsetelementnode.pass_2;
begin
{ load first value in 32bit register }
secondpass(left);
if left.location.loc in [LOC_REGISTER,LOC_CREGISTER] then
location_force_reg(exprasmlist,left.location,OS_32,false);
{ also a second value ? }
if assigned(right) then
begin
secondpass(right);
if codegenerror then
exit;
if right.location.loc in [LOC_REGISTER,LOC_CREGISTER] then
location_force_reg(exprasmlist,right.location,OS_32,false);
end;
{ we doesn't modify the left side, we check only the type }
location_copy(location,left.location);
end;
{*****************************************************************************
*****************************************************************************}
{**********************************************************************}
{ Description: Emit operation to do a bit test, where the bitnumber }
{ to test is in the bitnumber register. The value to test against is }
{ located in the value register. }
{ WARNING: Bitnumber register value is DESTROYED! }
{ __Result register is set to 1, if the bit is set otherwise, __Result}
{ is set to zero. __RESULT register is also used as scratch. }
{**********************************************************************}
procedure tcginnode.emit_bit_test_reg_reg(list : taasmoutput;
bitsize: tcgsize; bitnumber,value : tregister;
ressize: tcgsize; res :tregister);
begin
{ first make sure that the bit number is modulo 32 }
{ not necessary, since if it's > 31, we have a range error -> will }
{ be caught when range checking is on! (JM) }
{ cg.a_op_const_reg(list,OP_AND,31,bitnumber); }
if bitsize<>ressize then
begin
{ FIX ME! We're not allowed to modify the value register here! }
{ shift value register "bitnumber" bits to the right }
cg.a_op_reg_reg(list,OP_SHR,bitsize,bitnumber,value);
{ extract the bit we want }
cg.a_op_const_reg(list,OP_AND,bitsize,1,value);
cg.a_load_reg_reg(list,bitsize,ressize,value,res);
end
else
begin
{ rotate value register "bitnumber" bits to the right }
cg.a_op_reg_reg_reg(list,OP_SHR,bitsize,bitnumber,value,res);
{ extract the bit we want }
cg.a_op_const_reg(list,OP_AND,bitsize,1,res);
end;
end;
procedure tcginnode.pass_2;
type
Tsetpart=record
range : boolean; {Part is a range.}
start,stop : byte; {Start/stop when range; Stop=element when an element.}
end;
var
l,l3 : tasmlabel;
adjustment : aint;
href : treference;
hr,hr2,
pleftreg : tregister;
setparts : array[1..8] of Tsetpart;
opsize : tcgsize;
genjumps,
use_small : boolean;
i,numparts : byte;
function analizeset(const Aset:Tconstset;is_small:boolean):boolean;
var
compares,maxcompares:word;
i:byte;
begin
analizeset:=false;
numparts:=0;
compares:=0;
{ Lots of comparisions take a lot of time, so do not allow
too much comparisions. 8 comparisions are, however, still
smalller than emitting the set }
if cs_littlesize in aktglobalswitches then
maxcompares:=8
else
maxcompares:=5;
{ when smallset is possible allow only 3 compares the smallset
code is for littlesize also smaller when more compares are used }
if is_small then
maxcompares:=3;
for i:=0 to 255 do
if i in Aset then
begin
if (numparts=0) or (i<>setparts[numparts].stop+1) then
begin
{Set element is a separate element.}
inc(compares);
if compares>maxcompares then
exit;
inc(numparts);
setparts[numparts].range:=false;
setparts[numparts].stop:=i;
end
else
{Set element is part of a range.}
if not setparts[numparts].range then
begin
{Transform an element into a range.}
setparts[numparts].range:=true;
setparts[numparts].start:=setparts[numparts].stop;
setparts[numparts].stop:=i;
{ there's only one compare per range anymore. Only a }
{ sub is added, but that's much faster than a }
{ cmp/jcc combo so neglect its effect }
{ inc(compares);
if compares>maxcompares then
exit; }
end
else
begin
{Extend a range.}
setparts[numparts].stop:=i;
end;
end;
analizeset:=true;
end;
begin
{ We check first if we can generate jumps, this can be done
because the resulttype.def is already set in firstpass }
{ check if we can use smallset operation using btl which is limited
to 32 bits, the left side may also not contain higher values !! }
use_small:=(tsetdef(right.resulttype.def).settype=smallset) and
((left.resulttype.def.deftype=orddef) and (torddef(left.resulttype.def).high<=32) or
(left.resulttype.def.deftype=enumdef) and (tenumdef(left.resulttype.def).max<=32));
{ Can we generate jumps? Possible for all types of sets }
genjumps:=(right.nodetype=setconstn) and
analizeset(Tsetconstnode(right).value_set^,use_small);
opsize:=OS_32;
{ calculate both operators }
{ the complex one first }
firstcomplex(self);
secondpass(left);
{ Only process the right if we are not generating jumps }
if not genjumps then
secondpass(right);
if codegenerror then
exit;
{ ofcourse not commutative }
if nf_swaped in flags then
swapleftright;
{ location is always LOC_JUMP }
location_reset(location,LOC_REGISTER,def_cgsize(resulttype.def));
if genjumps then
begin
{ allocate a register for the result }
location.register := cg.getintregister(exprasmlist,location.size);
{ Get a label to jump to the end }
objectlibrary.getlabel(l);
{ clear the register value, indicating result is FALSE }
cg.a_load_const_reg(exprasmlist,location.size,0,location.register);
{ If register is used, use only lower 8 bits }
location_force_reg(exprasmlist,left.location,opsize,false);
pleftreg := left.location.register;
{ how much have we already substracted from the x in the }
{ "x in [y..z]" expression }
adjustment := 0;
hr:=NR_NO;
for i:=1 to numparts do
if setparts[i].range then
{ use fact that a <= x <= b <=> aword(x-a) <= aword(b-a) }
begin
{ is the range different from all legal values? }
if (setparts[i].stop-setparts[i].start <> 255) then
begin
{ yes, is the lower bound <> 0? }
if (setparts[i].start <> 0) then
{ we're going to substract from the left register, }
{ so in case of a LOC_CREGISTER first move the value }
{ to edi (not done before because now we can do the }
{ move and substract in one instruction with LEA) }
if (left.location.loc = LOC_CREGISTER) and
(hr<>pleftreg) then
begin
cg.a_op_const_reg(exprasmlist,OP_SUB,opsize,setparts[i].start,pleftreg);
hr:=cg.getintregister(exprasmlist,opsize);
cg.a_load_reg_reg(exprasmlist,opsize,opsize,pleftreg,hr);
pleftreg:=hr;
end
else
begin
{ otherwise, the value is already in a register }
{ that can be modified }
cg.a_op_const_reg(exprasmlist,OP_SUB,opsize,
setparts[i].start-adjustment,pleftreg)
end;
{ new total value substracted from x: }
{ adjustment + (setparts[i].start - adjustment) }
adjustment := setparts[i].start;
{ check if result < b-a+1 (not "result <= b-a", since }
{ we need a carry in case the element is in the range }
{ (this will never overflow since we check at the }
{ beginning whether stop-start <> 255) }
cg.a_cmp_const_reg_label(exprasmlist, opsize, OC_B,
setparts[i].stop-setparts[i].start+1,pleftreg,l);
end
else
{ if setparts[i].start = 0 and setparts[i].stop = 255, }
{ it's always true since "in" is only allowed for bytes }
begin
cg.a_jmp_always(exprasmlist,l);
end;
end
else
begin
{ Emit code to check if left is an element }
cg.a_cmp_const_reg_label(exprasmlist, opsize, OC_EQ,
setparts[i].stop-adjustment,pleftreg,l);
end;
{ To compensate for not doing a second pass }
right.location.reference.symbol:=nil;
objectlibrary.getlabel(l3);
cg.a_jmp_always(exprasmlist,l3);
{ Now place the end label if IN success }
cg.a_label(exprasmlist,l);
{ result register is 1 }
cg.a_load_const_reg(exprasmlist,location.size,1,location.register);
{ in case value is not found }
cg.a_label(exprasmlist,l3);
end
else
{*****************************************************************}
{ NO JUMP TABLE GENERATION }
{*****************************************************************}
begin
{ We will now generated code to check the set itself, no jmps,
handle smallsets separate, because it allows faster checks }
if use_small then
begin
{**************************** SMALL SET **********************}
if left.nodetype=ordconstn then
begin
location_force_reg(exprasmlist,right.location,opsize,true);
location.register:=cg.getintregister(exprasmlist,location.size);
{ first SHR the register }
cg.a_op_const_reg_reg(exprasmlist,OP_SHR,opsize,tordconstnode(left).value and 31,right.location.register,location.register);
{ then extract the lowest bit }
cg.a_op_const_reg(exprasmlist,OP_AND,opsize,1,location.register);
end
else
begin
location_force_reg(exprasmlist,left.location,opsize,false);
location_force_reg(exprasmlist,right.location,opsize,false);
{ allocate a register for the result }
location.register:=cg.getintregister(exprasmlist,location.size);
{ emit bit test operation }
emit_bit_test_reg_reg(exprasmlist,left.location.size,left.location.register,
right.location.register,location.size,location.register);
end;
end
else
{************************** NOT SMALL SET ********************}
begin
if right.location.loc=LOC_CONSTANT then
begin
{ can it actually occur currently? CEC }
{ yes: "if bytevar in [1,3,5,7,9,11,13,15]" (JM) }
{ note: this code assumes that left in [0..255], which is a valid }
{ assumption (other cases will be caught by range checking) (JM) }
{ load left in register }
location_force_reg(exprasmlist,left.location,opsize,true);
if left.location.loc = LOC_CREGISTER then
hr := cg.getintregister(exprasmlist,opsize)
else
hr := left.location.register;
{ load right in register }
hr2:=cg.getintregister(exprasmlist,opsize);
cg.a_load_const_reg(exprasmlist,opsize,right.location.value,hr2);
{ emit bit test operation }
emit_bit_test_reg_reg(exprasmlist,left.location.size,left.location.register,hr2,opsize,hr2);
{ if left > 31 then hr := 0 else hr := $ffffffff }
cg.a_op_const_reg_reg(exprasmlist,OP_SUB,opsize,32,left.location.register,hr);
cg.a_op_const_reg(exprasmlist,OP_SAR,opsize,31,hr);
{ if left > 31, then result := 0 else result := result of bit test }
cg.a_op_reg_reg(exprasmlist,OP_AND,opsize,hr,hr2);
{ allocate a register for the result }
location.register := cg.getintregister(exprasmlist,location.size);
cg.a_load_reg_reg(exprasmlist,opsize,location.size,hr2,location.register);
end { of right.location.loc=LOC_CONSTANT }
{ do search in a normal set which could have >32 elementsm
but also used if the left side contains higher values > 32 }
else if left.nodetype=ordconstn then
begin
{ use location.register as scratch register here }
if (target_info.endian = endian_little) then
inc(right.location.reference.offset,tordconstnode(left).value shr 3)
else
{ adjust for endianess differences }
inc(right.location.reference.offset,(tordconstnode(left).value shr 3) xor 3);
{ allocate a register for the result }
location.register := cg.getintregister(exprasmlist,location.size);
cg.a_load_ref_reg(exprasmlist,OS_8,location.size,right.location.reference, location.register);
cg.a_op_const_reg(exprasmlist,OP_SHR,location.size,tordconstnode(left).value and 7,
location.register);
cg.a_op_const_reg(exprasmlist,OP_AND,location.size,1,location.register);
end
else
begin
location_force_reg(exprasmlist,left.location,OS_INT,true);
pleftreg := left.location.register;
location_freetemp(exprasmlist,left.location);
hr := cg.getaddressregister(exprasmlist);
cg.a_op_const_reg_reg(exprasmlist,OP_SHR,OS_INT,5,pleftreg,hr);
cg.a_op_const_reg(exprasmlist,OP_SHL,OS_INT,2,hr);
href := right.location.reference;
if (href.base = NR_NO) then
href.base := hr
else if (right.location.reference.index = NR_NO) then
href.index := hr
else
begin
hr2 := cg.getaddressregister(exprasmlist);
cg.a_loadaddr_ref_reg(exprasmlist,href, hr2);
reference_reset_base(href,hr2,0);
href.index := hr;
end;
{ allocate a register for the result }
location.register := cg.getintregister(exprasmlist,opsize);
cg.a_load_ref_reg(exprasmlist,opsize,opsize,href,location.register);
hr := cg.getintregister(exprasmlist,opsize);
cg.a_op_const_reg_reg(exprasmlist,OP_AND,opsize,31,pleftreg,hr);
cg.a_op_reg_reg(exprasmlist,OP_SHR,opsize,hr,location.register);
cg.a_op_const_reg(exprasmlist,OP_AND,opsize,1,location.register);
end;
end;
end;
location_freetemp(exprasmlist,right.location);
end;
{*****************************************************************************
TCGCASENODE
*****************************************************************************}
function tcgcasenode.blocklabel(id:longint):tasmlabel;
begin
if not assigned(blocks[id]) then
internalerror(200411301);
result:=pcaseblock(blocks[id])^.blocklabel;
end;
procedure tcgcasenode.optimizevalues(var max_linear_list:aint;var max_dist:aword);
begin
{ no changes by default }
end;
function tcgcasenode.has_jumptable : boolean;
begin
{ No jumptable support in the default implementation }
has_jumptable:=false;
end;
procedure tcgcasenode.genjumptable(hp : pcaselabel;min_,max_ : aint);
begin
internalerror(200209161);
end;
procedure tcgcasenode.genlinearlist(hp : pcaselabel);
var
first : boolean;
last : TConstExprInt;
scratch_reg: tregister;
procedure genitem(t : pcaselabel);
procedure gensub(value:aint);
begin
{ here, since the sub and cmp are separate we need
to move the result before subtract to help
the register allocator
}
cg.a_load_reg_reg(exprasmlist, opsize, opsize, hregister, scratch_reg);
cg.a_op_const_reg(exprasmlist, OP_SUB, opsize, value, hregister);
end;
begin
if assigned(t^.less) then
genitem(t^.less);
{ do we need to test the first value? }
if first and (t^._low>get_min_value(left.resulttype.def)) then
cg.a_cmp_const_reg_label(exprasmlist,opsize,jmp_lt,aint(t^._low),hregister,elselabel);
if t^._low=t^._high then
begin
if t^._low-last=0 then
cg.a_cmp_const_reg_label(exprasmlist,opsize,OC_EQ,0,hregister,blocklabel(t^.blockid))
else
begin
gensub(aint(t^._low-last));
cg.a_cmp_const_reg_label(exprasmlist,opsize,OC_EQ,aint(t^._low-last),scratch_reg,blocklabel(t^.blockid));
end;
last:=t^._low;
end
else
begin
{ it begins with the smallest label, if the value }
{ is even smaller then jump immediately to the }
{ ELSE-label }
if first then
begin
{ have we to ajust the first value ? }
if (t^._low>get_min_value(left.resulttype.def)) then
gensub(aint(t^._low));
end
else
begin
{ if there is no unused label between the last and the }
{ present label then the lower limit can be checked }
{ immediately. else check the range in between: }
gensub(aint(t^._low-last));
cg.a_cmp_const_reg_label(exprasmlist, opsize,jmp_lt,aint(t^._low-last),scratch_reg,elselabel);
end;
gensub(aint(t^._high-t^._low));
cg.a_cmp_const_reg_label(exprasmlist,opsize,jmp_le,aint(t^._high-t^._low),scratch_reg,blocklabel(t^.blockid));
last:=t^._high;
end;
first:=false;
if assigned(t^.greater) then
genitem(t^.greater);
end;
begin
{ do we need to generate cmps? }
if (with_sign and (min_label<0)) then
genlinearcmplist(hp)
else
begin
last:=0;
first:=true;
scratch_reg:=cg.getintregister(exprasmlist,opsize);
genitem(hp);
cg.a_jmp_always(exprasmlist,elselabel);
end;
end;
procedure tcgcasenode.genlinearcmplist(hp : pcaselabel);
var
last : TConstExprInt;
lastwasrange: boolean;
procedure genitem(t : pcaselabel);
{$ifndef cpu64bit}
var
l1 : tasmlabel;
{$endif cpu64bit}
begin
if assigned(t^.less) then
genitem(t^.less);
if t^._low=t^._high then
begin
{$ifndef cpu64bit}
if opsize in [OS_S64,OS_64] then
begin
objectlibrary.getlabel(l1);
cg.a_cmp_const_reg_label(exprasmlist, OS_32, OC_NE, aint(hi(int64(t^._low))),hregister2,l1);
cg.a_cmp_const_reg_label(exprasmlist, OS_32, OC_EQ, aint(lo(int64(t^._low))),hregister, blocklabel(t^.blockid));
cg.a_label(exprasmlist,l1);
end
else
{$endif cpu64bit}
begin
cg.a_cmp_const_reg_label(exprasmlist, opsize, OC_EQ, aint(t^._low),hregister, blocklabel(t^.blockid));
end;
{ Reset last here, because we've only checked for one value and need to compare
for the next range both the lower and upper bound }
lastwasrange := false;
end
else
begin
{ it begins with the smallest label, if the value }
{ is even smaller then jump immediately to the }
{ ELSE-label }
if not lastwasrange or (t^._low-last>1) then
begin
{$ifndef cpu64bit}
if opsize in [OS_64,OS_S64] then
begin
objectlibrary.getlabel(l1);
cg.a_cmp_const_reg_label(exprasmlist, OS_32, jmp_lt, aint(hi(int64(t^._low))),
hregister2, elselabel);
cg.a_cmp_const_reg_label(exprasmlist, OS_32, jmp_gt, aint(hi(int64(t^._low))),
hregister2, l1);
{ the comparisation of the low dword must be always unsigned! }
cg.a_cmp_const_reg_label(exprasmlist, OS_32, OC_B, aint(lo(int64(t^._low))), hregister, elselabel);
cg.a_label(exprasmlist,l1);
end
else
{$endif cpu64bit}
begin
cg.a_cmp_const_reg_label(exprasmlist, opsize, jmp_lt, aint(t^._low), hregister,
elselabel);
end;
end;
{$ifndef cpu64bit}
if opsize in [OS_S64,OS_64] then
begin
objectlibrary.getlabel(l1);
cg.a_cmp_const_reg_label(exprasmlist, OS_32, jmp_lt, aint(hi(int64(t^._high))), hregister2,
blocklabel(t^.blockid));
cg.a_cmp_const_reg_label(exprasmlist, OS_32, jmp_gt, aint(hi(int64(t^._high))), hregister2,
l1);
cg.a_cmp_const_reg_label(exprasmlist, OS_32, OC_BE, aint(lo(int64(t^._high))), hregister, blocklabel(t^.blockid));
cg.a_label(exprasmlist,l1);
end
else
{$endif cpu64bit}
begin
cg.a_cmp_const_reg_label(exprasmlist, opsize, jmp_le, aint(t^._high), hregister, blocklabel(t^.blockid));
end;
last:=t^._high;
lastwasrange := true;
end;
if assigned(t^.greater) then
genitem(t^.greater);
end;
begin
last:=0;
lastwasrange:=false;
genitem(hp);
cg.a_jmp_always(exprasmlist,elselabel);
end;
procedure ReLabel(var p:tasmsymbol);
begin
if p.defbind = AB_LOCAL then
begin
if not assigned(p.altsymbol) then
objectlibrary.GenerateAltSymbol(p);
p:=p.altsymbol;
p.increfs;
end;
end;
procedure tcgcasenode.pass_2;
var
i : longint;
lv,hv,
max_label: tconstexprint;
labelcnt : aint;
max_linear_list : aint;
otl, ofl: tasmlabel;
isjump : boolean;
max_dist,
dist : aword;
begin
location_reset(location,LOC_VOID,OS_NO);
{ Allocate labels }
objectlibrary.getlabel(endlabel);
objectlibrary.getlabel(elselabel);
for i:=0 to blocks.count-1 do
objectlibrary.getlabel(pcaseblock(blocks[i])^.blocklabel);
with_sign:=is_signed(left.resulttype.def);
if with_sign then
begin
jmp_gt:=OC_GT;
jmp_lt:=OC_LT;
jmp_le:=OC_LTE;
end
else
begin
jmp_gt:=OC_A;
jmp_lt:=OC_B;
jmp_le:=OC_BE;
end;
{ save current truelabel and falselabel }
isjump:=false;
if left.location.loc=LOC_JUMP then
begin
otl:=truelabel;
objectlibrary.getlabel(truelabel);
ofl:=falselabel;
objectlibrary.getlabel(falselabel);
isjump:=true;
end;
secondpass(left);
{ determines the size of the operand }
opsize:=def_cgsize(left.resulttype.def);
{ copy the case expression to a register }
location_force_reg(exprasmlist,left.location,opsize,false);
{$ifndef cpu64bit}
if opsize in [OS_S64,OS_64] then
begin
hregister:=left.location.register64.reglo;
hregister2:=left.location.register64.reghi;
end
else
{$endif cpu64bit}
hregister:=left.location.register;
if isjump then
begin
truelabel:=otl;
falselabel:=ofl;
end;
{ we need the min_label always to choose between }
{ cmps and subs/decs }
min_label:=case_get_min(labels);
{ Generate the jumps }
{$ifdef OLDREGVARS}
load_all_regvars(exprasmlist);
{$endif OLDREGVARS}
{$ifndef cpu64bit}
if opsize in [OS_64,OS_S64] then
genlinearcmplist(labels)
else
{$endif cpu64bit}
begin
if cs_optimize in aktglobalswitches then
begin
{ procedures are empirically passed on }
{ consumption can also be calculated }
{ but does it pay on the different }
{ processors? }
{ moreover can the size only be appro- }
{ ximated as it is not known if rel8, }
{ rel16 or rel32 jumps are used }
max_label:=case_get_max(labels);
labelcnt:=case_count_labels(labels);
{ can we omit the range check of the jump table ? }
getrange(left.resulttype.def,lv,hv);
jumptable_no_range:=(lv=min_label) and (hv=max_label);
{ hack a little bit, because the range can be greater }
{ than the positive range of a aint }
if (min_label<0) and (max_label>0) then
begin
if min_label=TConstExprInt(low(aint)) then
dist:=aword(max_label)+aword(low(aint))
else
dist:=aword(max_label)+aword(-min_label)
end
else
dist:=max_label-min_label;
{ optimize for size ? }
if cs_littlesize in aktglobalswitches then
begin
if has_jumptable and
not((labelcnt<=2) or
((max_label-min_label)<0) or
((max_label-min_label)>3*labelcnt)) then
begin
{ if the labels less or more a continuum then }
genjumptable(labels,min_label,max_label);
end
else
begin
{ a linear list is always smaller than a jump tree }
genlinearlist(labels);
end;
end
else
begin
max_dist:=4*labelcnt;
if jumptable_no_range then
max_linear_list:=4
else
max_linear_list:=2;
{ allow processor specific values }
optimizevalues(max_linear_list,max_dist);
if (labelcnt<=max_linear_list) then
genlinearlist(labels)
else
begin
if (has_jumptable) and
(dist<max_dist) and
(min_label>=low(aint)) and
(max_label<=high(aint)) then
genjumptable(labels,min_label,max_label)
else
genlinearlist(labels);
end;
end;
end
else
{ it's always not bad }
genlinearlist(labels);
end;
{ generate the instruction blocks }
for i:=0 to blocks.count-1 do
begin
cg.a_label(exprasmlist,pcaseblock(blocks[i])^.blocklabel);
secondpass(pcaseblock(blocks[i])^.statement);
{ don't come back to case line }
aktfilepos:=exprasmList.getlasttaifilepos^;
{$ifdef OLDREGVARS}
load_all_regvars(exprasmlist);
{$endif OLDREGVARS}
cg.a_jmp_always(exprasmlist,endlabel);
end;
{ ...and the else block }
cg.a_label(exprasmlist,elselabel);
if assigned(elseblock) then
begin
secondpass(elseblock);
{$ifdef OLDREGVARS}
load_all_regvars(exprasmlist);
{$endif OLDREGVARS}
end;
cg.a_label(exprasmlist,endlabel);
{ Reset labels }
for i:=0 to blocks.count-1 do
pcaseblock(blocks[i])^.blocklabel:=nil;
end;
begin
csetelementnode:=tcgsetelementnode;
cinnode:=tcginnode;
ccasenode:=tcgcasenode;
end.
{
$Log$
Revision 1.74 2005-01-04 20:14:40 florian
* better commenting
Revision 1.73 2004/12/11 01:04:26 jonas
* fixed regvar problem due to emit_bit_test() changing a register that
was allowed to be a LOC_CREGISTER
Revision 1.72 2004/12/05 12:28:11 peter
* procvar handling for tp procvar mode fixed
* proc to procvar moved from addrnode to typeconvnode
* inlininginfo is now allocated only for inline routines that
can be inlined, introduced a new flag po_has_inlining_info
Revision 1.71 2004/11/30 18:13:39 jonas
* patch from Peter to fix inlining of case statements
Revision 1.70 2004/10/31 21:45:03 peter
* generic tlocation
* move tlocation to cgutils
Revision 1.69 2004/10/30 22:01:11 florian
* jmp table code generation for case statement on sparc
Revision 1.68 2004/09/25 14:23:54 peter
* ungetregister is now only used for cpuregisters, renamed to
ungetcpuregister
* renamed (get|unget)explicitregister(s) to ..cpuregister
* removed location-release/reference_release
Revision 1.67 2004/08/25 11:51:31 jonas
* fixed rare case bug (see tests/test/tb0478.pp)
Revision 1.66 2004/08/16 21:00:15 peter
* range checks fixed
Revision 1.65 2004/07/22 10:07:09 jonas
* fixed relabeling (nextaltnr was never increased)
* fixed inlining of case statements at the node level
Revision 1.64 2004/07/04 12:38:55 jonas
* fixed regvar bug in tcginnode.pass_2
Revision 1.63 2004/06/20 08:55:29 florian
* logs truncated
Revision 1.62 2004/06/16 20:07:08 florian
* dwarf branch merged
Revision 1.61 2004/05/30 21:18:22 jonas
* some optimizations and associated fixes for better regvar code
Revision 1.60.2.5 2004/05/02 16:49:12 peter
* 64 bit fixes
Revision 1.60.2.4 2004/05/02 14:09:54 peter
* fix case 64bit issues
Revision 1.60.2.3 2004/05/01 16:02:09 peter
* POINTER_SIZE replaced with sizeof(aint)
* aint,aword,tconst*int moved to globtype
}