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llvm: fix reading past end of data for some parameter references

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Fixes false positives when using address sanitizer
This commit is contained in:
Jonas Maebe 2022-07-06 21:15:07 +02:00
parent b2ea782eb4
commit 1ab6fc9a4b
1 changed files with 19 additions and 7 deletions
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26
compiler/llvm/hlcgllvm.pas
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@ -342,15 +342,28 @@ implementation
var
newrefsize: tdef;
reg: tregister;
tmpref: treference;
begin
newrefsize:=llvmgetcgparadef(para,true,callerside);
if (refsize<>newrefsize) and
(initialref.refaddr<>addr_full) then
begin
reg:=getaddressregister(list,cpointerdef.getreusable(newrefsize));
a_loadaddr_ref_reg(list,refsize,cpointerdef.getreusable(newrefsize),initialref,reg);
reference_reset_base(newref,cpointerdef.getreusable(newrefsize),reg,0,initialref.temppos,initialref.alignment,initialref.volatility);
refsize:=newrefsize;
if refsize.size>=newrefsize.size then
begin
reg:=getaddressregister(list,cpointerdef.getreusable(newrefsize));
a_loadaddr_ref_reg(list,refsize,cpointerdef.getreusable(newrefsize),initialref,reg);
reference_reset_base(newref,cpointerdef.getreusable(newrefsize),reg,0,initialref.temppos,initialref.alignment,initialref.volatility);
refsize:=newrefsize;
end
else
begin
tg.gethltemp(list,newrefsize,newrefsize.size,tt_normal,newref);
reg:=getaddressregister(list,cpointerdef.getreusable(refsize));
a_loadaddr_ref_reg(list,newrefsize,cpointerdef.getreusable(refsize),newref,reg);
reference_reset_base(tmpref,refsize,reg,0,newref.temppos,newref.alignment,initialref.volatility);
g_concatcopy(list,refsize,initialref,tmpref);
refsize:=newrefsize;
end;
end
else
newref:=initialref;
@ -1246,10 +1259,9 @@ implementation
begin
{ perform small copies directly; not larger ones, because then llvm
will try to load the entire large datastructure into registers and
starts spilling like crazy; too small copies must not be done via
llvm.memcpy either, because then you get crashes in llvm }
starts spilling like crazy }
if (size.typ in [orddef,floatdef,enumdef]) or
(size.size<=2*sizeof(aint)) then
(size.size in [1,2,4,8]) then
begin
a_load_ref_ref(list,size,size,source,dest);
exit;