void LegalizeMD::LegalizeDst(IR::Instr * instr, bool fPostRegAlloc)
{
LegalForms forms = LegalDstForms(instr);
IR::Opnd * opnd = instr->GetDst();
if (opnd == NULL)
{
#ifdef DBG
// No legalization possible, just report error.
if (forms != 0)
{
IllegalInstr(instr, L"Expected dst opnd");
}
#endif
return;
}
switch (opnd->GetKind())
{
case IR::OpndKindReg:
#ifdef DBG
// No legalization possible, just report error.
if (!(forms & L_RegMask))
{
IllegalInstr(instr, L"Unexpected reg dst");
}
#endif
break;
case IR::OpndKindMemRef:
{
// MemRefOpnd is a deference of the memory location.
// So extract the location, load it to register, replace the MemRefOpnd with an IndirOpnd taking the
// register as base, and fall through to legalize the IndirOpnd.
void *memLoc = opnd->AsMemRefOpnd()->GetMemLoc();
IR::RegOpnd *newReg = IR::RegOpnd::New(TyMachPtr, instr->m_func);
if (fPostRegAlloc)
{
newReg->SetReg(SCRATCH_REG);
}
IR::Instr *newInstr = IR::Instr::New(Js::OpCode::LDIMM, newReg,
IR::AddrOpnd::New(memLoc, opnd->AsMemRefOpnd()->GetAddrKind(), instr->m_func, true), instr->m_func);
instr->InsertBefore(newInstr);
LegalizeMD::LegalizeInstr(newInstr, fPostRegAlloc);
IR::IndirOpnd *indirOpnd = IR::IndirOpnd::New(newReg, 0, opnd->GetType(), instr->m_func);
opnd = instr->ReplaceDst(indirOpnd);
}
// FALL THROUGH
case IR::OpndKindIndir:
if (!(forms & L_IndirMask))
{
instr = LegalizeStore(instr, forms, fPostRegAlloc);
forms = LegalDstForms(instr);
}
LegalizeIndirOffset(instr, opnd->AsIndirOpnd(), forms, fPostRegAlloc);
break;
case IR::OpndKindSym:
if (!(forms & L_SymMask))
{
instr = LegalizeStore(instr, forms, fPostRegAlloc);
forms = LegalDstForms(instr);
}
if (fPostRegAlloc)
{
// In order to legalize SymOffset we need to know final argument area, which is only available after lowerer.
// So, don't legalize sym offset here, but it will be done as part of register allocator.
LegalizeSymOffset(instr, opnd->AsSymOpnd(), forms, fPostRegAlloc);
}
break;
default:
AssertMsg(UNREACHED, "Unexpected dst opnd kind");
break;
}
}
