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#define XERR
#include "semval.ih"
void SemVal::patch(vector<unsigned> &list, PatchDest dest)
{
if (list.empty())
return;
unsigned patchDest = dest == END ? d_code.size() : 0;
// offset is the offset immediately beyond the jump instruction
// including the two bytes jmp offset following the jmp, jf, jt
// instruction. This is the position where the jump
// starts after having read the jump instruction. Hence, the
// jumpsize is determined by the distance 'patchDest - offset',
// whereas this jumpsize must be inserted 2 bytes before offset
// because that's where jmp reads the #bytes the jmp must skip
//xerr("size: " << list.size());
for (unsigned offset: list)
{
//cerr << "insert jump size at " << (offset - 2) << '\n';
short jumpSize = patchDest - offset;
//cerr << "jump size: " << hex << jumpSize << dec << '\n';
endian(&d_code[offset - 2], jumpSize);
}
//cerr << '\n';
list.clear(); // this patch is completed, code may be
// appended to which this patch-vector no
// longer applies.
}
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