const PassInfo *llvm::SimpleRegisterCoalescingID = X.getPassInfo();
void SimpleRegisterCoalescing::getAnalysisUsage(AnalysisUsage &AU) const {
- //AU.addPreserved<LiveVariables>();
AU.addPreserved<LiveIntervals>();
AU.addPreservedID(PHIEliminationID);
AU.addPreservedID(TwoAddressInstructionPassID);
return true;
}
+/// AddSubRegIdxPairs - Recursively mark all the registers represented by the
+/// specified register as sub-registers. The recursion level is expected to be
+/// shallow.
+void SimpleRegisterCoalescing::AddSubRegIdxPairs(unsigned Reg, unsigned SubIdx) {
+ std::vector<unsigned> &JoinedRegs = r2rRevMap_[Reg];
+ for (unsigned i = 0, e = JoinedRegs.size(); i != e; ++i) {
+ SubRegIdxes.push_back(std::make_pair(JoinedRegs[i], SubIdx));
+ AddSubRegIdxPairs(JoinedRegs[i], SubIdx);
+ }
+}
+
/// JoinCopy - Attempt to join intervals corresponding to SrcReg/DstReg,
/// which are the src/dst of the copy instruction CopyMI. This returns true
/// if the copy was successfully coalesced away, or if it is never possible
std::swap(repSrcReg, repDstReg);
std::swap(ResSrcInt, ResDstInt);
}
- SubRegIdxes.push_back(std::make_pair(DstReg,
- CopyMI->getOperand(2).getImm()));
+ unsigned SubIdx = CopyMI->getOperand(2).getImm();
+ SubRegIdxes.push_back(std::make_pair(repSrcReg, SubIdx));
+ AddSubRegIdxPairs(repSrcReg, SubIdx);
}
DOUT << "\n\t\tJoined. Result = "; ResDstInt->print(DOUT, mri_);
// being merged.
li_->removeInterval(repSrcReg);
r2rMap_[repSrcReg] = repDstReg;
+ r2rRevMap_[repDstReg].push_back(repSrcReg);
// Finally, delete the copy instruction.
li_->RemoveMachineInstrFromMaps(CopyMI);
}
DOUT << "*** Register mapping ***\n";
- for (int i = 0, e = r2rMap_.size(); i != e; ++i)
+ for (unsigned i = 0, e = r2rMap_.size(); i != e; ++i)
if (r2rMap_[i]) {
DOUT << " reg " << i << " -> ";
DEBUG(printRegName(r2rMap_[i]));
}
void SimpleRegisterCoalescing::releaseMemory() {
- r2rMap_.clear();
- JoinedLIs.clear();
- SubRegIdxes.clear();
+ for (unsigned i = 0, e = r2rMap_.size(); i != e; ++i)
+ r2rRevMap_[i].clear();
+ r2rRevMap_.clear();
+ r2rMap_.clear();
+ JoinedLIs.clear();
+ SubRegIdxes.clear();
}
static bool isZeroLengthInterval(LiveInterval *li) {
SSARegMap *RegMap = mf_->getSSARegMap();
r2rMap_.grow(RegMap->getLastVirtReg());
+ r2rRevMap_.grow(RegMap->getLastVirtReg());
// Join (coalesce) intervals if requested.
if (EnableJoining) {
DOUT << "\n";
}
- // Track coalesced sub-registers.
+ // Transfer sub-registers info to SSARegMap now that coalescing information
+ // is complete.
while (!SubRegIdxes.empty()) {
std::pair<unsigned, unsigned> RI = SubRegIdxes.back();
SubRegIdxes.pop_back();