paweld/fpc
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/fpc/source.git synced 2025-04-11 14:48:47 +02:00
Code Issues Packages Projects Releases Wiki Activity

* Improved the parentfp optimization to properly handle cases when a nested routine calls other nested routines.

Browse Source 
git-svn-id: trunk@45665 -
This commit is contained in:
yury 2020-06-20 18:34:26 +00:00
parent c15b6f4516
commit 7bffafdf8b
6 changed files with 44 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
compiler/ncal.pas
View File

@ -3516,7 +3516,19 @@ implementation
if not assigned(right) then
begin
if assigned(procdefinition.owner.defowner) then
hiddentree:=cloadparentfpnode.create(tprocdef(procdefinition.owner.defowner),lpf_forpara)
begin
if paramanager.can_opt_unused_para(currpara) and
(procdefinition<>current_procinfo.procdef) then
{ If parentfp is unused by the target proc, create loadparentfpnode which loads
the current frame pointer to prevent generation of unneeded code. }
hiddentree:=cloadparentfpnode.create(current_procinfo.procdef,lpf_forpara)
else
begin
hiddentree:=cloadparentfpnode.create(tprocdef(procdefinition.owner.defowner),lpf_forpara);
if is_nested_pd(current_procinfo.procdef) then
current_procinfo.set_needs_parentfp(tprocdef(procdefinition.owner.defowner).parast.symtablelevel);
end;
end
{ exceptfilters called from main level are not owned }
else if procdefinition.proctypeoption=potype_exceptfilter then
hiddentree:=cloadparentfpnode.create(current_procinfo.procdef,lpf_forpara)

27
compiler/ncgcal.pas
View File

@ -138,29 +138,6 @@ implementation
wpobase;
function can_opt_unused_para(parasym: tparavarsym): boolean;
var
pd: tprocdef;
begin
{ The parameter can be optimized as unused when:
optimization level 1 and higher
this is a direct call to a routine, not a procvar
and the routine is not an exception filter
and the parameter is not used by the routine
and implementation of the routine is already processed.
}
result:=(cs_opt_level1 in current_settings.optimizerswitches) and
assigned(parasym.Owner) and
(parasym.Owner.defowner.typ=procdef);
if not result then
exit;
pd:=tprocdef(parasym.Owner.defowner);
result:=(pd.proctypeoption<>potype_exceptfilter) and
not parasym.is_used and
pd.is_implemented;
end;
function can_skip_para_push(parasym: tparavarsym): boolean;
begin
{ We can skip passing the parameter when:
@ -169,7 +146,7 @@ implementation
and fixed stack is used
or the parameter is in a register
or the parameter is $parentfp. }
result:=can_opt_unused_para(parasym) and
result:=paramanager.can_opt_unused_para(parasym) and
not paramanager.has_strict_proc_signature and
(paramanager.use_fixed_stack or
(vo_is_parentfp in parasym.varoptions) or
@ -322,7 +299,7 @@ implementation
function tcgcallparanode.maybe_push_unused_para: boolean;
begin
{ Check if the parameter is unused and can be optimized }
result:=can_opt_unused_para(parasym);
result:=paramanager.can_opt_unused_para(parasym);
if not result then
exit;
{ If we can't skip loading of the parameter, load an undefined dummy value. }

1
compiler/nld.pas
View File

@ -357,6 +357,7 @@ implementation
if assigned(left) then
internalerror(200309289);
left:=cloadparentfpnode.create(tprocdef(symtable.defowner),lpf_forload);
current_procinfo.set_needs_parentfp(tprocdef(symtable.defowner).parast.symtablelevel);
{ reference in nested procedures, variable needs to be in memory }
{ and behaves as if its address escapes its parent block }
make_not_regable(self,[ra_different_scope]);

2
compiler/nmem.pas
View File

@ -316,8 +316,6 @@ implementation
internalerror(200309284);
parentpd:=pd;
kind:=fpkind;
if current_procinfo.procdef.parast.symtablelevel>pd.parast.symtablelevel then
current_procinfo.set_needs_parentfp(pd.parast.symtablelevel);
end;

25
compiler/paramgr.pas
View File

@ -165,6 +165,8 @@ unit paramgr;
and checked by the runtime/backend compiler (e.g. JVM, LLVM).
The default implementation returns false. }
function has_strict_proc_signature: boolean; virtual;
{ Returns true if parasym is unused and can be optimized. }
function can_opt_unused_para(parasym: tparavarsym): boolean;
strict protected
{ common part of get_funcretloc; returns true if retloc is completely
initialized afterwards }
@ -195,6 +197,7 @@ implementation
uses
systems,
globals,
cgobj,tgobj,
defutil,verbose,
hlcgobj;
@ -833,6 +836,28 @@ implementation
end;
function tparamanager.can_opt_unused_para(parasym: tparavarsym): boolean;
var
pd: tprocdef;
begin
{ The parameter can be optimized as unused when:
optimization level 1 and higher
this is a direct call to a routine, not a procvar
and the routine is not an exception filter
and the parameter is not used by the routine
and implementation of the routine is already processed.
}
result:=(cs_opt_level1 in current_settings.optimizerswitches) and
assigned(parasym.Owner) and
(parasym.Owner.defowner.typ=procdef);
if not result then
exit;
pd:=tprocdef(parasym.Owner.defowner);
result:=(pd.proctypeoption<>potype_exceptfilter) and
not parasym.is_used and
pd.is_implemented;
end;
initialization
;
finalization

5
compiler/procinfo.pas
View File

@ -439,9 +439,10 @@ implementation
pi : tprocinfo;
p : tparavarsym;
begin
if (procdef.parast.symtablelevel<=normal_function_level)
or (procdef.parast.symtablelevel<=parent_level) then
if procdef.parast.symtablelevel<=normal_function_level then
Internalerror(2020050302);
if procdef.parast.symtablelevel<=parent_level then
exit;
if parent_level<normal_function_level then
parent_level:=normal_function_level;
{ Mark parentfp as used for the current proc }