pint_t getEncodedP(pint_t &addr, pint_t end, uint8_t encoding,
const unw_proc_info_t *ctx) {
pint_t startAddr = addr;
const uint8_t *p = (uint8_t *)addr;
pint_t result;
if (encoding == DW_EH_PE_omit)
return 0;
if (encoding == DW_EH_PE_aligned) {
addr = (addr + sizeof(pint_t) - 1) & sizeof(pint_t);
return getP(addr);
}
// first get value
switch (encoding & 0x0F) {
case DW_EH_PE_ptr:
result = getP(addr);
p += sizeof(pint_t);
addr = (pint_t)p;
break;
case DW_EH_PE_uleb128:
result = getULEB128(addr, end);
break;
case DW_EH_PE_udata2:
result = get16(addr);
p += 2;
addr = (pint_t)p;
break;
case DW_EH_PE_udata4:
result = get32(addr);
p += 4;
addr = (pint_t)p;
break;
case DW_EH_PE_udata8:
result = get64(addr);
p += 8;
addr = (pint_t)p;
break;
case DW_EH_PE_sleb128:
result = getSLEB128(addr, end);
break;
case DW_EH_PE_sdata2:
result = (int16_t)get16(addr);
p += 2;
addr = (pint_t)p;
break;
case DW_EH_PE_sdata4:
result = (int32_t)get32(addr);
p += 4;
addr = (pint_t)p;
break;
case DW_EH_PE_sdata8:
result = get64(addr);
p += 8;
addr = (pint_t)p;
break;
case DW_EH_PE_omit:
result = 0;
break;
default:
assert(0 && "unknown pointer encoding");
}
// then add relative offset
switch (encoding & 0x70) {
case DW_EH_PE_absptr:
// do nothing
break;
case DW_EH_PE_pcrel:
result += startAddr;
break;
case DW_EH_PE_textrel:
assert(0 && "DW_EH_PE_textrel pointer encoding not supported");
break;
case DW_EH_PE_datarel:
assert(ctx != NULL && "DW_EH_PE_datarel without context");
if (ctx)
result += ctx->data_base;
break;
case DW_EH_PE_funcrel:
assert(ctx != NULL && "DW_EH_PE_funcrel without context");
if (ctx)
result += ctx->start_ip;
break;
case DW_EH_PE_aligned:
__builtin_unreachable();
default:
assert(0 && "unknown pointer encoding");
break;
}
if (encoding & DW_EH_PE_indirect)
result = getP(result);
return result;
}
LocalAddressSpace::pint_t
LocalAddressSpace::getEncodedP(pint_t& addr, pint_t end, uint8_t encoding)
{
pint_t startAddr = addr;
const uint8_t* p = (uint8_t*)addr;
pint_t result;
// first get value
switch (encoding & 0x0F) {
case DW_EH_PE_ptr:
result = getP(addr);
p += sizeof(pint_t);
addr = (pint_t)p;
break;
case DW_EH_PE_uleb128:
result = getULEB128(addr, end);
break;
case DW_EH_PE_udata2:
result = get16(addr);
p += 2;
addr = (pint_t)p;
break;
case DW_EH_PE_udata4:
result = get32(addr);
p += 4;
addr = (pint_t)p;
break;
case DW_EH_PE_udata8:
result = get64(addr);
p += 8;
addr = (pint_t)p;
break;
case DW_EH_PE_sleb128:
result = getSLEB128(addr, end);
break;
case DW_EH_PE_sdata2:
result = (int16_t)get16(addr);
p += 2;
addr = (pint_t)p;
break;
case DW_EH_PE_sdata4:
result = (int32_t)get32(addr);
p += 4;
addr = (pint_t)p;
break;
case DW_EH_PE_sdata8:
result = get64(addr);
p += 8;
addr = (pint_t)p;
break;
default:
ABORT("unknown pointer encoding");
}
// then add relative offset
switch ( encoding & 0x70 ) {
case DW_EH_PE_absptr:
// do nothing
break;
case DW_EH_PE_pcrel:
result += startAddr;
break;
case DW_EH_PE_textrel:
ABORT("DW_EH_PE_textrel pointer encoding not supported");
break;
case DW_EH_PE_datarel:
ABORT("DW_EH_PE_datarel pointer encoding not supported");
break;
case DW_EH_PE_funcrel:
ABORT("DW_EH_PE_funcrel pointer encoding not supported");
break;
case DW_EH_PE_aligned:
ABORT("DW_EH_PE_aligned pointer encoding not supported");
break;
default:
ABORT("unknown pointer encoding");
break;
}
if ( encoding & DW_EH_PE_indirect )
result = getP(result);
return result;
}
