All registers created during splitting or spilling are assigned to the same
stack slot as the parent register.
When splitting or rematting, we may not spill at all. In that case the stack
slot is still assigned, but it will be dead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116546
91177308-0d34-0410-b5e6-
96231b3b80d8
return;
rc_ = mri_.getRegClass(edit.getReg());
- stackSlot_ = vrm_.getStackSlot(edit.getReg());
- if (stackSlot_ == VirtRegMap::NO_STACK_SLOT)
- stackSlot_ = vrm_.assignVirt2StackSlot(edit.getReg());
+ stackSlot_ = edit.assignStackSlot(vrm_);
// Iterate over instructions using register.
for (MachineRegisterInfo::reg_iterator RI = mri_.reg_begin(edit.getReg());
using namespace llvm;
+int LiveRangeEdit::assignStackSlot(VirtRegMap &vrm) {
+ int ss = vrm.getStackSlot(getReg());
+ if (ss != VirtRegMap::NO_STACK_SLOT)
+ return ss;
+ return vrm.assignVirt2StackSlot(getReg());
+}
+
LiveInterval &LiveRangeEdit::create(MachineRegisterInfo &mri,
LiveIntervals &lis,
VirtRegMap &vrm) {
const TargetRegisterClass *RC = mri.getRegClass(parent_.reg);
unsigned VReg = mri.createVirtualRegister(RC);
vrm.grow();
+ // Immediately assign to the same stack slot as parent.
+ vrm.assignVirt2StackSlot(VReg, assignStackSlot(vrm));
LiveInterval &li = lis.getOrCreateInterval(VReg);
newRegs_.push_back(&li);
return li;
iterator begin() const { return newRegs_.begin()+firstNew_; }
iterator end() const { return newRegs_.end(); }
- /// create - Create a new register with the same class as parentReg_.
+ /// assignStackSlot - Ensure a stack slot is assigned to parent.
+ /// @return the assigned stack slot number.
+ int assignStackSlot(VirtRegMap&);
+
+ /// create - Create a new register with the same class and stack slot as
+ /// parent.
LiveInterval &create(MachineRegisterInfo&, LiveIntervals&, VirtRegMap&);
/// allUsesAvailableAt - Return true if all registers used by OrigMI at
openli_(lis_, *curli_)
{
assert(curli_ && "SplitEditor created from empty SplitAnalysis");
-
- // Make sure curli_ is assigned a stack slot, so all our intervals get the
- // same slot as curli_.
- if (vrm_.getStackSlot(curli_->reg) == VirtRegMap::NO_STACK_SLOT)
- vrm_.assignVirt2StackSlot(curli_->reg);
-
}
bool SplitEditor::intervalsLiveAt(SlotIndex Idx) const {