paweld/fpc
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/fpc/source.git synced 2025-04-09 00:08:12 +02:00
Code Issues Packages Projects Releases Wiki Activity

* tcg.a_load_cgparaloc_ref checks the size of the ref exactly to avoid overwriting of adjacent data

Browse Source 
git-svn-id: trunk@36951 -
This commit is contained in:
florian 2017-08-20 15:21:59 +00:00
parent 9b3e0a80df
commit 43b017bde0
1 changed files with 123 additions and 51 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

174
compiler/cgobj.pas
View File

@ -1091,57 +1091,129 @@ implementation
hreg : tregister;
cgsize: tcgsize;
begin
case paraloc.loc of
LOC_REGISTER :
begin
hreg:=paraloc.register;
cgsize:=paraloc.size;
if paraloc.shiftval>0 then
a_op_const_reg_reg(list,OP_SHL,OS_INT,paraloc.shiftval,paraloc.register,paraloc.register)
{ in case the original size was 3 or 5/6/7 bytes, the value was
shifted to the top of the to 4 resp. 8 byte register on the
caller side and needs to be stored with those bytes at the
start of the reference -> don't shift right }
else if (paraloc.shiftval<0) and
((-paraloc.shiftval) in [1,2,4]) then
begin
a_op_const_reg_reg(list,OP_SHR,OS_INT,-paraloc.shiftval,paraloc.register,paraloc.register);
{ convert to a register of 1/2/4 bytes in size, since the
original register had to be made larger to be able to hold
the shifted value }
cgsize:=int_cgsize(tcgsize2size[OS_INT]-(-paraloc.shiftval div 8));
hreg:=getintregister(list,cgsize);
a_load_reg_reg(list,OS_INT,cgsize,paraloc.register,hreg);
end;
a_load_reg_ref(list,paraloc.size,cgsize,hreg,ref);
end;
LOC_MMREGISTER :
begin
case paraloc.size of
OS_F32,
OS_F64,
OS_F128:
a_loadmm_reg_ref(list,paraloc.size,paraloc.size,paraloc.register,ref,mms_movescalar);
OS_M8..OS_M128,
OS_MS8..OS_MS128:
a_loadmm_reg_ref(list,paraloc.size,paraloc.size,paraloc.register,ref,nil);
else
internalerror(2010053102);
end;
end;
LOC_FPUREGISTER :
a_loadfpu_reg_ref(list,paraloc.size,paraloc.size,paraloc.register,ref);
LOC_REFERENCE :
begin
reference_reset_base(href,paraloc.reference.index,paraloc.reference.offset,align,[]);
{ use concatcopy, because it can also be a float which fails when
load_ref_ref is used. Don't copy data when the references are equal }
if not((href.base=ref.base) and (href.offset=ref.offset)) then
g_concatcopy(list,href,ref,sizeleft);
end;
else
internalerror(2002081302);
end;
case paraloc.loc of
LOC_REGISTER :
begin
hreg:=paraloc.register;
cgsize:=paraloc.size;
if paraloc.shiftval>0 then
a_op_const_reg_reg(list,OP_SHL,OS_INT,paraloc.shiftval,paraloc.register,paraloc.register)
{ in case the original size was 3 or 5/6/7 bytes, the value was
shifted to the top of the to 4 resp. 8 byte register on the
caller side and needs to be stored with those bytes at the
start of the reference -> don't shift right }
else if (paraloc.shiftval<0) and
((-paraloc.shiftval) in [8,16,32]) then
begin
a_op_const_reg_reg(list,OP_SHR,OS_INT,-paraloc.shiftval,paraloc.register,paraloc.register);
{ convert to a register of 1/2/4 bytes in size, since the
original register had to be made larger to be able to hold
the shifted value }
cgsize:=int_cgsize(tcgsize2size[OS_INT]-(-paraloc.shiftval div 8));
hreg:=getintregister(list,cgsize);
a_load_reg_reg(list,OS_INT,cgsize,paraloc.register,hreg);
end;
{ use the exact size to avoid overwriting of adjacent data }
if tcgsize2size[cgsize]<=sizeleft then
a_load_reg_ref(list,paraloc.size,cgsize,hreg,ref)
else
case sizeleft of
1,2,4,8:
a_load_reg_ref(list,paraloc.size,int_cgsize(sizeleft),hreg,ref);
3:
begin
if target_info.endian=endian_big then
begin
href:=ref;
inc(href.offset,2);
a_load_reg_ref(list,paraloc.size,OS_8,hreg,href);
a_op_const_reg_reg(list,OP_SHR,OS_INT,8,hreg,hreg);
a_load_reg_ref(list,paraloc.size,OS_16,hreg,ref);
end
else
{ little endian not implemented yet }
Internalerror(2017081301);
end;
5:
begin
if target_info.endian=endian_big then
begin
href:=ref;
inc(href.offset,4);
a_load_reg_ref(list,paraloc.size,OS_8,hreg,href);
a_op_const_reg_reg(list,OP_SHR,OS_INT,8,hreg,hreg);
a_load_reg_ref(list,paraloc.size,OS_32,hreg,ref);
end
else
{ little endian not implemented yet }
Internalerror(2017081302);
end;
6:
begin
if target_info.endian=endian_big then
begin
href:=ref;
inc(href.offset,4);
a_load_reg_ref(list,paraloc.size,OS_16,hreg,href);
a_op_const_reg_reg(list,OP_SHR,OS_INT,16,hreg,hreg);
a_load_reg_ref(list,paraloc.size,OS_32,hreg,ref);
end
else
{ little endian not implemented yet }
Internalerror(2017081303);
end;
7:
begin
if target_info.endian=endian_big then
begin
href:=ref;
inc(href.offset,6);
a_load_reg_ref(list,paraloc.size,OS_8,hreg,href);
a_op_const_reg_reg(list,OP_SHR,OS_INT,8,hreg,hreg);
href:=ref;
inc(href.offset,4);
a_load_reg_ref(list,paraloc.size,OS_16,hreg,href);
a_op_const_reg_reg(list,OP_SHR,OS_INT,16,hreg,hreg);
a_load_reg_ref(list,paraloc.size,OS_32,hreg,ref);
end
else
{ little endian not implemented yet }
Internalerror(2017081304);
end;
else
{ other sizes not allowed }
Internalerror(2017080901);
end;
end;
LOC_MMREGISTER :
begin
case paraloc.size of
OS_F32,
OS_F64,
OS_F128:
a_loadmm_reg_ref(list,paraloc.size,paraloc.size,paraloc.register,ref,mms_movescalar);
OS_M8..OS_M128,
OS_MS8..OS_MS128:
a_loadmm_reg_ref(list,paraloc.size,paraloc.size,paraloc.register,ref,nil);
else
internalerror(2010053102);
end;
end;
LOC_FPUREGISTER :
a_loadfpu_reg_ref(list,paraloc.size,paraloc.size,paraloc.register,ref);
LOC_REFERENCE :
begin
reference_reset_base(href,paraloc.reference.index,paraloc.reference.offset,align,[]);
{ use concatcopy, because it can also be a float which fails when
load_ref_ref is used. Don't copy data when the references are equal }
if not((href.base=ref.base) and (href.offset=ref.offset)) then
g_concatcopy(list,href,ref,sizeleft);
end;
else
internalerror(2002081302);
end;
end;