public override ElfSymbol RelocateEntry(Program program, ElfSymbol sym, ElfSection referringSection, ElfRelocation rela)
{
if (loader.Sections.Count <= sym.SectionIndex)
{
return(sym);
}
if (sym.SectionIndex == 0)
{
return(sym);
}
var symSection = loader.Sections[(int)sym.SectionIndex];
uint S = (uint)sym.Value;
uint A = (uint)rela.Addend;
uint P = (uint)rela.Offset;
var addr = Address.Ptr32(P);
uint PP = P;
var arch = program.Architecture;
var relR = program.CreateImageReader(arch, addr);
var relW = program.CreateImageWriter(arch, addr);
var rt = (PpcRt)(rela.Info & 0xFF);
switch (rt)
{
case PpcRt.R_PPC_GLOB_DAT:
case PpcRt.R_PPC_COPY:
case PpcRt.R_PPC_JMP_SLOT:
break;
case PpcRt.R_PPC_ADDR32:
relW.WriteUInt32(S + A);
break;
case PpcRt.R_PPC_REL24:
uint wInstr = relR.ReadUInt32();
// 24 bit relocation where bits 3-29 are used for relocations
uint value = (S + A - P);
wInstr = (wInstr & 0xFC000003) | (value & 0x03FFFFFC);
relW.WriteUInt32(wInstr);
break;
case PpcRt.R_PPC_ADDR16_HI:
case PpcRt.R_PPC_ADDR16_HA:
// Wait for the following R_PPC_ADDR16_LO relocation.
prevPpcHi16 = rela;
prevRelR = relR;
prevRelW = relW;
break;
case PpcRt.R_PPC_ADDR16_LO:
if (prevPpcHi16 == null)
{
return(sym);
}
uint valueHi = prevRelR.ReadUInt16();
uint valueLo = relR.ReadUInt16();
if ((PpcRt)(prevPpcHi16.Info & 0xFF) == PpcRt.R_PPC_ADDR16_HA)
{
valueHi += (valueHi & 0x8000u) != 0 ? 1u : 0u;
}
value = (valueHi << 16) | valueLo;
value += S;
valueHi = (value >> 16) & 0xFFFF;
valueLo = value & 0xFFFF;
prevRelW.WriteBeUInt16((ushort)valueHi);
relW.WriteBeUInt16((ushort)valueLo);
break;
default:
if (!missedRelocations.TryGetValue(rt, out var count))
{
count = 0;
}
missedRelocations[rt] = count + 1;
break;
}
return(sym);
}