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Commit 88009b38 authored by Jason Hiser's avatar Jason Hiser :tractor:
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dealing with limitations of arm assembler

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include/ehwrite.h
+ 2
− 0
View file @ 88009b38
......@@ -117,6 +117,8 @@ class EhWriterImpl_t : public EhWriter_t
std::vector<FDErepresentation_t*> all_fdes;
std::vector<CIErepresentation_t*> all_cies;
VirtualOffset_t eh_frame_hdr_addr; // where the eh frame hdr will land.
void BuildFDEs();
void GenerateEhOutput();
void CompileEhOutput();
......
src/ehwrite.cpp
+ 91
− 88
View file @ 88009b38
......@@ -34,6 +34,26 @@ template < typename T > std::string to_hex_string( const T& n )
template<int ptrsize>
void EhWriterImpl_t<ptrsize>::GenerateNewEhInfo()
{
auto page_round_up=[](const uintptr_t x) -> uintptr_t
{
auto page_size=(uintptr_t)PAGE_SIZE;
return ( (((uintptr_t)(x)) + page_size-1) & (~(page_size-1)) );
};
// find maximum used scoop address.
const auto max_used_addr=std::max_element(
zipr_obj.getFileIR()->getDataScoops().begin(),
zipr_obj.getFileIR()->getDataScoops().end(),
[&](const DataScoop_t* a, const DataScoop_t* b)
{
assert(a && b && a->getEnd() && b->getEnd()) ;
return a->getEnd()->getVirtualOffset() < b->getEnd()->getVirtualOffset();
}
);
// round it up and stringify it.
eh_frame_hdr_addr=page_round_up((*max_used_addr)->getEnd()->getVirtualOffset());
BuildFDEs();
GenerateEhOutput();
......@@ -920,7 +940,7 @@ void EhWriterImpl_t<ptrsize>::GenerateEhOutput()
first=false;
out<<"0x"<<hex<<setfill('0')<<setw(2)<<((int)c&0xff);
}
out << " # " << p.getPrintableString(s)<<endl;
out << " // " << p.getPrintableString(s)<<endl;
}
out.flags(flags); // restore flags
};
......@@ -1016,31 +1036,31 @@ void EhWriterImpl_t<ptrsize>::GenerateEhOutput()
const auto cs_end_addr=zipr_obj.GetLocationMap()->at(cs.cs_insn_start)+cs.cs_insn_start->getDataBits().size();
const auto cs_len=cs_end_addr-cs_start_addr;
out<<"LSDA"<<dec<<lsda_num<<"_cs_tab_entry"<<cs_num<<"_start:"<<endl;
out<<" # 1) start of call site relative to FDE start addr (call site encoding)"<<endl;
out<<" // 1) start of call site relative to FDE start addr (call site encoding)"<<endl;
out<<" .sleb128 0x"<<hex<<cs_start_addr<<" - 0x"<<hex<<fde->start_addr<<endl;
out<<" # 2) length of call site (call site encoding)"<<endl;
out<<" // 2) length of call site (call site encoding)"<<endl;
out<<" .sleb128 "<<dec<<cs_len<<endl;
if(cs.landing_pad)
{
const auto lp_addr=zipr_obj.GetLocationMap()->at(cs.landing_pad);
out<<" # 3) the landing pad, or 0 if none exists. (call site encoding)"<<endl;
out<<" // 3) the landing pad, or 0 if none exists. (call site encoding)"<<endl;
out<<" .sleb128 0x"<<hex<<lp_addr<<" - 0x"<<hex<<landing_pad_base<<endl;
}
else
{
out<<" # 3) the landing pad, or 0 if none exists. (call site encoding)"<<endl;
out<<" // 3) the landing pad, or 0 if none exists. (call site encoding)"<<endl;
out<<" .sleb128 0"<<endl;
}
if(cs.actions.size() > 0 )
{
out<<" # 4) index into action table + 1 -- 0 indicates unwind only (call site encoding)"<<endl;
out<<" // 4) index into action table + 1 -- 0 indicates unwind only (call site encoding)"<<endl;
out<<" .sleb128 1 + LSDA"<<dec<<lsda_num<<"_act"
<<cs.action_table_index<<"_start_entry0 - LSDA"<<dec<<lsda_num<<"_action_tab_start"<<endl;
}
else
{
out<<" # 4) index into action table + 1 -- 0 indicates unwind only (always uleb)"<<endl;
out<<" .uleb128 0 # no actions!" << endl;
out<<" // 4) index into action table + 1 -- 0 indicates unwind only (always uleb)"<<endl;
out<<" .uleb128 0 // no actions!" << endl;
}
out<<"LSDA"<<dec<<lsda_num<<"_cs_tab_entry"<<cs_num<<"_end:"<<endl;
......@@ -1050,28 +1070,28 @@ void EhWriterImpl_t<ptrsize>::GenerateEhOutput()
{
if(landing_pad_base==fde->start_addr)
{
out<<" # 1) encoding of next field "<<endl;
out<<" .byte 0xff # DW_EH_PE_omit (0xff)"<<endl;
out<<" // 1) encoding of next field "<<endl;
out<<" .byte 0xff // DW_EH_PE_omit (0xff)"<<endl;
out<<""<<endl;
out<<" # 2) landing pad base, if omitted, use FDE start addr"<<endl;
out<<" # .<fdebasetype> <fdebase> -- omitted. "<<endl;
out<<" // 2) landing pad base, if omitted, use FDE start addr"<<endl;
out<<" // .<fdebasetype> <fdebase> -- omitted. "<<endl;
}
else
{
out<<" # 1) encoding of next field "<<endl;
out<<" .byte 0x1b # DW_EH_PE_pcrel (0x10) |sdata4 (0xb)"<<endl;
out<<" // 1) encoding of next field "<<endl;
out<<" .byte 0x1b // DW_EH_PE_pcrel (0x10) |sdata4 (0xb)"<<endl;
out<<""<<endl;
out<<" # 2) landing pad base, if omitted, use FDE start addr"<<endl;
out<<" .int 0x"<<hex<<landing_pad_base<<"- . # as pcrel|sdata4 . "<<endl;
out<<" // 2) landing pad base, if omitted, use FDE start addr"<<endl;
out<<" .int 0x"<<hex<<landing_pad_base<<"- . // as pcrel|sdata4 . "<<endl;
}
out<<""<<endl;
out<<" # 3) encoding of type table entries"<<endl;
out<<" .byte 0x"<<hex<<lsda->tt_encoding<<" # DW_EH_PE_udata4"<<endl;
out<<" // 3) encoding of type table entries"<<endl;
out<<" .byte 0x"<<hex<<lsda->tt_encoding<<" // DW_EH_PE_udata4"<<endl;
out<<""<<endl;
out<<" # 4) type table pointer -- always a uleb128"<<endl;
out<<" // 4) type table pointer -- always a uleb128"<<endl;
if(lsda->tt_encoding==0xff) /* omit */
{
out<<" # .uleb128 LSDAptr omitted"<< endl;
out<<" // .uleb128 LSDAptr omitted"<< endl;
}
else
{
......@@ -1079,10 +1099,10 @@ void EhWriterImpl_t<ptrsize>::GenerateEhOutput()
}
out<<"LSDA"<<dec<<lsda_num<<"_tt_ptr_end:"<<endl;
out<<""<<endl;
out<<" # 5) call site table encoding"<<endl;
out<<" .byte 0x9 # DW_EH_PE_sleb128 "<<endl;
out<<" // 5) call site table encoding"<<endl;
out<<" .byte 0x9 // DW_EH_PE_sleb128 "<<endl;
out<<""<<endl;
out<<" # 6) the length of the call site table"<<endl;
out<<" // 6) the length of the call site table"<<endl;
out<<" .uleb128 LSDA"<<dec<<lsda_num<<"_cs_tab_end-LSDA"<<dec<<lsda_num<<"_cs_tab_start"<<endl;
out<<"LSDA"<<dec<<lsda_num<<"_cs_tab_start:"<<endl;
};
......@@ -1117,12 +1137,12 @@ void EhWriterImpl_t<ptrsize>::GenerateEhOutput()
if(reloc==nullptr)
{
// indicates a catch all or empty type table entry
out<<" .int 0x0 # not used!"<<endl;
out<<" .int 0x0 // not used!"<<endl;
}
else if(reloc->getWRT()==nullptr)
{
// indicates a catch all or empty type table entry
out<<" .int 0x0 # catch all "<<endl;
out<<" .int 0x0 // catch all "<<endl;
}
else
{
......@@ -1131,7 +1151,7 @@ void EhWriterImpl_t<ptrsize>::GenerateEhOutput()
assert(scoop);
const auto final_addr=scoop->getStart()->getVirtualOffset() + reloc->getAddend();
if(((lsda->tt_encoding)&0x10) == 0x10) // if encoding contains pcrel (0x10).
out<<" .int 0x"<<hex<<final_addr<<" - . "<<endl;
out<<" .int 0x"<<hex<<final_addr<<" + eh_frame_hdr_start - . - "<<eh_frame_hdr_addr<<endl;
else
out<<" .int 0x"<<hex<<final_addr<<endl;
......@@ -1162,52 +1182,52 @@ void EhWriterImpl_t<ptrsize>::GenerateEhOutput()
const auto cie_pos=cie_pos_it-all_cies.begin();
cie->has_been_output=true;
out<<"# cie "<<dec<<cie_pos<<""<<endl;
out<<"// cie "<<dec<<cie_pos<<""<<endl;
out<<"Lcie"<<cie_pos<<":"<<endl;
out<<" .int Lcie"<<cie_pos<<"_end - Lcie"<<cie_pos<<" - 4 # length of this record. -4 because length doesn't include this field"<<endl;
out<<" .int 0 # cie (not fde)"<<endl;
out<<" .byte 3 # version"<<endl;
out<<" .asciz \"zPLR\" # aug string."<<endl;
out<<" .uleb128 "<<dec<<cie->code_alignment_factor<<" # code alignment factor"<<endl;
out<<" .sleb128 "<<dec<<cie->data_alignment_factor<<" # data alignment factor"<<endl;
out<<" .uleb128 "<<dec<<cie->return_reg<<" # return address reg."<<endl;
out<<" # encode the Z (length)"<<endl;
out<<" .sleb128 Lcie"<<cie_pos<<"_aug_data_end-Lcie"<<cie_pos<<"_aug_data_start # Z -- handle length field"<<endl;
out<<" .int Lcie"<<cie_pos<<"_end - Lcie"<<cie_pos<<" - 4 // length of this record. -4 because length doesn't include this field"<<endl;
out<<" .int 0 // cie (not fde)"<<endl;
out<<" .byte 3 // version"<<endl;
out<<" .asciz \"zPLR\" // aug string."<<endl;
out<<" .uleb128 "<<dec<<cie->code_alignment_factor<<" // code alignment factor"<<endl;
out<<" .sleb128 "<<dec<<cie->data_alignment_factor<<" // data alignment factor"<<endl;
out<<" .uleb128 "<<dec<<cie->return_reg<<" // return address reg."<<endl;
out<<" // encode the Z (length)"<<endl;
out<<" .sleb128 Lcie"<<cie_pos<<"_aug_data_end-Lcie"<<cie_pos<<"_aug_data_start // Z -- handle length field"<<endl;
out<<"Lcie"<<cie_pos<<"_aug_data_start:"<<endl;
out<<""<<endl;
if(personality_scoop)
{
auto personality_value=personality_scoop->getStart()->getVirtualOffset()+personality_addend;
out<<" #encode the P (personality encoding + personality routine)"<<endl;
out<<" .byte 0x80 | 0x10 | 0x0B # personality pointer encoding DH_EH_PE_indirect (0x80) | pcrel | sdata4"<<endl;
out<<" .int "<<personality_value<<" - . # actual personality routine, encoded as noted in prev line."<<endl;
out<<" //encode the P (personality encoding + personality routine)"<<endl;
out<<" .byte 0x80 | 0x10 | 0x0B // personality pointer encoding DH_EH_PE_indirect (0x80) | pcrel | sdata4"<<endl;
out<<" .int "<<personality_value<<" + eh_frame_hdr_start - . - "<<eh_frame_hdr_addr<<" // actual personality routine, encoded as noted in prev line."<<endl;
}
else if(personality_insn)
{
const auto personality_insn_addr=zipr_obj.GetLocationMap()->at(personality_insn);
const auto personality_value=personality_insn_addr+personality_addend;
out<<" #encode the P (personality encoding + personality routine)"<<endl;
out<<" .byte 0x10 | 0x0B # personality pointer encoding pcrel | sdata4"<<endl;
out<<" .int "<<personality_value<<" - . # actual personality routine, encoded as noted in prev line."<<endl;
out<<" //encode the P (personality encoding + personality routine)"<<endl;
out<<" .byte 0x10 | 0x0B // personality pointer encoding pcrel | sdata4"<<endl;
out<<" .int "<<personality_value<<" + eh_frame_hdr_start - . - "<<eh_frame_hdr_addr<<" // actual personality routine, encoded as noted in prev line."<<endl;
}
else
{
assert(cie->personality_reloc==nullptr || cie->personality_reloc->getWRT()==nullptr);
out<<" #encode the P (personality encoding + personality routine)"<<endl;
out<<" .byte 0x0B # personality pointer encoding sdata4"<<endl;
out<<" .int 0 # actual personality routine, encoded as noted in prev line."<<endl;
out<<" //encode the P (personality encoding + personality routine)"<<endl;
out<<" .byte 0x0B // personality pointer encoding sdata4"<<endl;
out<<" .int 0 // actual personality routine, encoded as noted in prev line."<<endl;
}
out<<""<<endl;
out<<" # encode L (lsda encoding) "<<endl;
out<<" .byte 0x1b # LSDA encoding (pcrel|sdata4)"<<endl;
out<<" // encode L (lsda encoding) "<<endl;
out<<" .byte 0x1b // LSDA encoding (pcrel|sdata4)"<<endl;
out<<""<<endl;
out<<" # encode R (FDE encoding) "<<endl;
out<<" .byte 0x10 | 0x0B # FDE encoding (pcrel | sdata4)"<<endl;
out<<" // encode R (FDE encoding) "<<endl;
out<<" .byte 0x10 | 0x0B // FDE encoding (pcrel | sdata4)"<<endl;
out<<"Lcie"<<cie_pos<<"_aug_data_end:"<<endl;
out<<" # CIE program"<<endl;
out<<" // CIE program"<<endl;
output_program(cie->pgm,out);
out<<""<<endl;
out<<" # pad with nops"<<endl;
out<<" // pad with nops"<<endl;
out<<" .align 4, 0"<<endl;
out<<"Lcie"<<cie_pos<<"_end:"<<endl;
......@@ -1222,26 +1242,26 @@ void EhWriterImpl_t<ptrsize>::GenerateEhOutput()
assert(cie_pos_it!=all_cies.end());
auto cie_pos=cie_pos_it-all_cies.begin();
out<<"#fde "<<dec<<fde_num<<""<<endl;
out<<"//fde "<<dec<<fde_num<<""<<endl;
out<<"Lfde"<<fde_num<<":"<<endl;
out<<" .int Lfde"<<fde_num<<"_end - Lfde"<<fde_num<<" - 4 # length of this record. -4 because "
out<<" .int Lfde"<<fde_num<<"_end - Lfde"<<fde_num<<" - 4 // length of this record. -4 because "
"length doesn't include this field."<<endl;
out<<" .int . - Lcie"<<cie_pos<<" # this is an FDE (not a "
out<<" .int . - Lcie"<<cie_pos<<" // this is an FDE (not a "
"cie), and it's cie is CIE"<<cie_pos<<". byte offset from start of field."<<endl;
out<<" .int 0x"<<hex<<fde->start_addr<<dec<<" - . # FDE start addr"<<endl;
out<<" .int "<<dec<<fde->end_addr-fde->start_addr<<" # fde range length (i.e., can calc the "
out<<" .int 0x"<<hex<<fde->start_addr<<dec<<" + eh_frame_hdr_start - . - "<<eh_frame_hdr_addr<<" // FDE start addr"<<endl;
out<<" .int "<<dec<<fde->end_addr-fde->start_addr<<" // fde range length (i.e., can calc the "
"fde_end_addr from this -- note that pcrel is ignored here!)"<<endl;
out<<" #encode Z (length)"<<endl;
out<<" //encode Z (length)"<<endl;
out<<" .uleb128 Lfde"<<fde_num<<"_aug_data_end-Lfde"<<fde_num<<"_aug_data_start"<<endl;
out<<"Lfde"<<fde_num<<"_aug_data_start:"<<endl;
out<<" #encode L (LSDA) "<<endl;
out<<" //encode L (LSDA) "<<endl;
if(fde->hasLsda())
out<<" .int LSDA"<<fde_num<<" - . # LSDA hard coded here (as pcrel+sdata4)"<<endl;
out<<" .int LSDA"<<fde_num<<" - . // LSDA hard coded here (as pcrel+sdata4)"<<endl;
else
out<<" .int 0-. # no LSDA, encoded with pcrel "<<endl;
out<<" .int 0 + eh_frame_hdr_start - . + "<<eh_frame_hdr_addr<<" // no LSDA, encoded with pcrel "<<endl;
out<<"Lfde"<<fde_num<<"_aug_data_end:"<<endl;
out<<""<<endl;
out<<" # FDE"<<fde_num<<" program"<<endl;
out<<" // FDE"<<fde_num<<" program"<<endl;
output_program(fde->pgm,out);
out<<" .align 4, 0"<<endl;
out<<" Lfde"<<fde_num<<"_end:"<<endl;
......@@ -1251,22 +1271,22 @@ void EhWriterImpl_t<ptrsize>::GenerateEhOutput()
{
out<<".section eh_frame_hdr, \"a\", @progbits"<<endl;
out<<"eh_frame_hdr_start:"<<endl;
out<<" .byte 1 # version"<<endl;
out<<" .byte 0x10 | 0x0B # encoding for pointer to eh-frame -- DH_EH_PE_pcrel (0x10) | DH_EH_PE_sdata4 (0x0B)"<<endl;
out<<" .byte 0x03 # encoding for ; of entries in eh-frame-hdr -- BDH_EH_PE_udata4 (0x03)"<<endl;
out<<" .byte 0x30 | 0x0B # encoding for pointers (to fdes) held in the eh-frame-hdr header "
out<<" .byte 1 // version"<<endl;
out<<" .byte 0x10 | 0x0B // encoding for pointer to eh-frame -- DH_EH_PE_pcrel (0x10) | DH_EH_PE_sdata4 (0x0B)"<<endl;
out<<" .byte 0x03 // encoding for ; of entries in eh-frame-hdr -- BDH_EH_PE_udata4 (0x03)"<<endl;
out<<" .byte 0x30 | 0x0B // encoding for pointers (to fdes) held in the eh-frame-hdr header "
"-- DH_EH_PE_datarel (0x30) | DH_EH_PE_sdata4 (0x0b) " <<endl;
out<<" .int Lfde_table - . # pointer to fde_table, encoded as an sdata4, pcrel"<<endl;
out<<" .int (eh_frame_table_end-eh_frame_table)/8 # number of FDEs in the header."<<endl;
out<<" .int Lfde_table - . // pointer to fde_table, encoded as an sdata4, pcrel"<<endl;
out<<" .int (eh_frame_table_end-eh_frame_table)/8 // number of FDEs in the header."<<endl;
out<<" .align 4"<<endl;
out<<"eh_frame_table:"<<endl;
out<<" # fde pointers"<<endl;
out<<" // fde pointers"<<endl;
for(auto fde_num=0U; fde_num < all_fdes.size(); fde_num++)
{
const auto& fde=all_fdes[fde_num];
out<<" .int 0x"<<hex<<fde->start_addr<<" - eh_frame_hdr_start"<<endl;
out<<" .int 0x"<<hex<<fde->start_addr<<" - "<<eh_frame_hdr_addr<<endl;
out<<" .int Lfde"<<dec<<fde_num<<" - eh_frame_hdr_start"<<endl;
}
......@@ -1276,7 +1296,7 @@ void EhWriterImpl_t<ptrsize>::GenerateEhOutput()
auto generate_eh_frame=[&](ostream& out) -> void
{
out<<".section eh_frame, \"a\", @progbits"<<endl;
out<<"Lfde_table: # needed for xref to eh_frame_hdr" <<endl;
out<<"Lfde_table: // needed for xref to eh_frame_hdr" <<endl;
auto fde_num=0;
for(const auto& fde: all_fdes)
......@@ -1309,29 +1329,12 @@ void EhWriterImpl_t<ptrsize>::GenerateEhOutput()
template<int ptrsize>
void EhWriterImpl_t<ptrsize>::CompileEhOutput()
{
auto page_round_up=[](const uintptr_t x) -> uintptr_t
{
auto page_size=(uintptr_t)PAGE_SIZE;
return ( (((uintptr_t)(x)) + page_size-1) & (~(page_size-1)) );
};
// find maximum used scoop address.
const auto max_used_addr=std::max_element(
zipr_obj.getFileIR()->getDataScoops().begin(),
zipr_obj.getFileIR()->getDataScoops().end(),
[&](const DataScoop_t* a, const DataScoop_t* b)
{
assert(a && b && a->getEnd() && b->getEnd()) ;
return a->getEnd()->getVirtualOffset() < b->getEnd()->getVirtualOffset();
}
);
// round it up and stringify it.
const auto eh_frame_hdr_addr=page_round_up((*max_used_addr)->getEnd()->getVirtualOffset());
const auto eh_frame_hdr_addr_str=to_hex_string(eh_frame_hdr_addr);
// create and execute the command to build the ehframe.
auto cmd=(string)"$PEASOUP_HOME/tools/eh_frame_tools/eh_to_bin.sh "+ehframe_s_filename+" "+eh_frame_hdr_addr_str+" "+ehframe_exe_filename;
cout<<"Running: "<<cmd<<endl;
auto res=system(cmd.c_str());
// err check.
......
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