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* assume that compilerprocs never capture the addresses of their arguments

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git-svn-id: trunk@31489 -
This commit is contained in:
Jonas Maebe 2015-09-03 13:35:59 +00:00
parent 2b551d0241
commit ee3f89246c
1 changed files with 34 additions and 16 deletions
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50
compiler/ncal.pas
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@ -1306,7 +1306,12 @@ implementation
{ uninitialized warnings (tbs/tb0542) }
set_varstate(left,vs_written,[]);
set_varstate(left,vs_readwritten,[]);
make_not_regable(left,[ra_addr_regable,ra_addr_taken]);
{ compilerprocs never capture the address of their
parameters }
if not(po_compilerproc in aktcallnode.procdefinition.procoptions) then
make_not_regable(left,[ra_addr_regable,ra_addr_taken])
else
make_not_regable(left,[ra_addr_regable])
end;
vs_var,
vs_constref:
@ -1315,7 +1320,12 @@ implementation
{ constref takes also the address, but storing it is actually the compiler
is not supposed to expect }
if parasym.varspez=vs_var then
make_not_regable(left,[ra_addr_regable,ra_addr_taken]);
{ compilerprocs never capture the address of their
parameters }
if not(po_compilerproc in aktcallnode.procdefinition.procoptions) then
make_not_regable(left,[ra_addr_regable,ra_addr_taken])
else
make_not_regable(left,[ra_addr_regable])
end;
else
set_varstate(left,vs_read,[vsf_must_be_valid]);
@ -2885,21 +2895,28 @@ implementation
(procdefinition.parast.symtablelevel=normal_function_level) and
{ must be a local variable, a value para or a hidden function result }
{ parameter (which can be passed by address, but in that case it got }
{ through these same checks at the caller side and is thus safe }
(
(tloadnode(realassignmenttarget).symtableentry.typ=localvarsym) or
{ through these same checks at the caller side and is thus safe ) }
{ other option: we're calling a compilerproc, because those don't
rely on global state
}
((po_compilerproc in procdefinition.procoptions) or
(
(tloadnode(realassignmenttarget).symtableentry.typ=paravarsym) and
((tparavarsym(tloadnode(realassignmenttarget).symtableentry).varspez = vs_value) or
(vo_is_funcret in tparavarsym(tloadnode(realassignmenttarget).symtableentry).varoptions))
(
(tloadnode(realassignmenttarget).symtableentry.typ=localvarsym) or
(
(tloadnode(realassignmenttarget).symtableentry.typ=paravarsym) and
((tparavarsym(tloadnode(realassignmenttarget).symtableentry).varspez = vs_value) or
(vo_is_funcret in tparavarsym(tloadnode(realassignmenttarget).symtableentry).varoptions))
)
) and
{ the address may not have been taken of the variable/parameter, because }
{ otherwise it's possible that the called function can access it via a }
{ global variable or other stored state }
(
not(tabstractvarsym(tloadnode(realassignmenttarget).symtableentry).addr_taken) and
(tabstractvarsym(tloadnode(realassignmenttarget).symtableentry).varregable in [vr_none,vr_addr])
)
)
) and
{ the address may not have been taken of the variable/parameter, because }
{ otherwise it's possible that the called function can access it via a }
{ global variable or other stored state }
(
not(tabstractvarsym(tloadnode(realassignmenttarget).symtableentry).addr_taken) and
(tabstractvarsym(tloadnode(realassignmenttarget).symtableentry).varregable in [vr_none,vr_addr])
) then
begin
{ If the funcret is also used as a parameter we can't optimize because the funcret
@ -4050,7 +4067,8 @@ implementation
function result" is not something which can be stored
persistently by the callee (it becomes invalid when the callee
returns) }
if not(vo_is_funcret in hp.parasym.varoptions) then
if not(vo_is_funcret in hp.parasym.varoptions) and
not(po_compilerproc in procdefinition.procoptions) then
make_not_regable(hp.left,[ra_addr_regable,ra_addr_taken])
else
make_not_regable(hp.left,[ra_addr_regable]);