diff options
| -rw-r--r-- | include/llvm/CodeGen/LiveInterval.h | 6 | ||||
| -rw-r--r-- | lib/CodeGen/RegAllocLinearScan.cpp | 24 |
2 files changed, 23 insertions, 7 deletions
diff --git a/include/llvm/CodeGen/LiveInterval.h b/include/llvm/CodeGen/LiveInterval.h index a50fef9..3fb0c1d 100644 --- a/include/llvm/CodeGen/LiveInterval.h +++ b/include/llvm/CodeGen/LiveInterval.h @@ -275,14 +275,16 @@ namespace llvm { /// beginNumber - Return the lowest numbered slot covered by interval. unsigned beginNumber() const { - assert(!empty() && "empty interval for register"); + if (empty()) + return 0; return ranges.front().start; } /// endNumber - return the maximum point of the interval of the whole, /// exclusive. unsigned endNumber() const { - assert(!empty() && "empty interval for register"); + if (empty()) + return 0; return ranges.back().end; } diff --git a/lib/CodeGen/RegAllocLinearScan.cpp b/lib/CodeGen/RegAllocLinearScan.cpp index 6925de3..19c7da1 100644 --- a/lib/CodeGen/RegAllocLinearScan.cpp +++ b/lib/CodeGen/RegAllocLinearScan.cpp @@ -322,11 +322,13 @@ void RALinScan::linearScan() ++NumIters; DOUT << "\n*** CURRENT ***: " << *cur << '\n'; - processActiveIntervals(cur->beginNumber()); - processInactiveIntervals(cur->beginNumber()); + if (!cur->empty()) { + processActiveIntervals(cur->beginNumber()); + processInactiveIntervals(cur->beginNumber()); - assert(TargetRegisterInfo::isVirtualRegister(cur->reg) && - "Can only allocate virtual registers!"); + assert(TargetRegisterInfo::isVirtualRegister(cur->reg) && + "Can only allocate virtual registers!"); + } // Allocating a virtual register. try to find a free // physical register or spill an interval (possibly this one) in order to @@ -508,11 +510,23 @@ void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur) { DOUT << "\tallocating current interval: "; + // This is an implicitly defined live interval, just assign any register. + const TargetRegisterClass *RC = reginfo_->getRegClass(cur->reg); + if (cur->empty()) { + unsigned physReg = cur->preference; + if (!physReg) + physReg = *RC->allocation_order_begin(*mf_); + DOUT << tri_->getName(physReg) << '\n'; + // Note the register is not really in use. + vrm_->assignVirt2Phys(cur->reg, physReg); + handled_.push_back(cur); + return; + } + PhysRegTracker backupPrt = *prt_; std::vector<std::pair<unsigned, float> > SpillWeightsToAdd; unsigned StartPosition = cur->beginNumber(); - const TargetRegisterClass *RC = reginfo_->getRegClass(cur->reg); const TargetRegisterClass *RCLeader = RelatedRegClasses.getLeaderValue(RC); // If this live interval is defined by a move instruction and its source is |