/// This class holds information about a machine level values, including
/// definition and use points.
///
- /// Care must be taken in interpreting the def index of the value. The
+ /// Care must be taken in interpreting the def index of the value. The
/// following rules apply:
///
/// If the isDefAccurate() method returns false then def does not contain the
IS_DEF_ACCURATE = 1 << 4
};
+ MachineInstr *copy;
unsigned char flags;
- union {
- MachineInstr *copy;
- unsigned reg;
- } cr;
public:
- typedef SpecificBumpPtrAllocator<VNInfo> Allocator;
+ typedef BumpPtrAllocator Allocator;
/// The ID number of this value.
unsigned id;
/// d is presumed to point to the actual defining instr. If it doesn't
/// setIsDefAccurate(false) should be called after construction.
VNInfo(unsigned i, SlotIndex d, MachineInstr *c)
- : flags(IS_DEF_ACCURATE), id(i), def(d) { cr.copy = c; }
+ : copy(c), flags(IS_DEF_ACCURATE), id(i), def(d)
+ { }
/// VNInfo construtor, copies values from orig, except for the value number.
VNInfo(unsigned i, const VNInfo &orig)
- : flags(orig.flags), cr(orig.cr), id(i), def(orig.def)
+ : copy(orig.copy), flags(orig.flags), id(i), def(orig.def)
{ }
/// Copy from the parameter into this VNInfo.
void copyFrom(VNInfo &src) {
flags = src.flags;
- cr = src.cr;
+ copy = src.copy;
def = src.def;
}
/// For a register interval, if this VN was definied by a copy instr
/// getCopy() returns a pointer to it, otherwise returns 0.
/// For a stack interval the behaviour of this method is undefined.
- MachineInstr* getCopy() const { return cr.copy; }
+ MachineInstr* getCopy() const { return copy; }
/// For a register interval, set the copy member.
/// This method should not be called on stack intervals as it may lead to
/// undefined behavior.
- void setCopy(MachineInstr *c) { cr.copy = c; }
-
- /// For a stack interval, returns the reg which this stack interval was
- /// defined from.
- /// For a register interval the behaviour of this method is undefined.
- unsigned getReg() const { return cr.reg; }
- /// For a stack interval, set the defining register.
- /// This method should not be called on register intervals as it may lead
- /// to undefined behaviour.
- void setReg(unsigned reg) { cr.reg = reg; }
+ void setCopy(MachineInstr *c) { copy = c; }
/// Returns true if one or more kills are PHI nodes.
bool hasPHIKill() const { return flags & HAS_PHI_KILL; }
}
/// containsRange - Return true if the given range, [S, E), is covered by
- /// this range.
+ /// this range.
bool containsRange(SlotIndex S, SlotIndex E) const {
assert((S < E) && "Backwards interval?");
return (start <= S && S < end) && (start < E && E <= end);
float weight; // weight of this interval
Ranges ranges; // the ranges in which this register is live
VNInfoList valnos; // value#'s
-
+
struct InstrSlots {
enum {
LOAD = 0,
while (I->end <= Pos) ++I;
return I;
}
-
+
void clear() {
valnos.clear();
ranges.clear();
bool containsOneValue() const { return valnos.size() == 1; }
unsigned getNumValNums() const { return (unsigned)valnos.size(); }
-
+
/// getValNumInfo - Returns pointer to the specified val#.
///
inline VNInfo *getValNumInfo(unsigned ValNo) {
/// the instruction that defines the value number.
VNInfo *getNextValue(SlotIndex def, MachineInstr *CopyMI,
bool isDefAccurate, VNInfo::Allocator &VNInfoAllocator) {
- VNInfo *VNI = VNInfoAllocator.Allocate();
- new (VNI) VNInfo((unsigned)valnos.size(), def, CopyMI);
+ VNInfo *VNI =
+ new (VNInfoAllocator) VNInfo((unsigned)valnos.size(), def, CopyMI);
VNI->setIsDefAccurate(isDefAccurate);
valnos.push_back(VNI);
return VNI;
/// for the Value number.
VNInfo *createValueCopy(const VNInfo *orig,
VNInfo::Allocator &VNInfoAllocator) {
- VNInfo *VNI = VNInfoAllocator.Allocate();
- new (VNI) VNInfo((unsigned)valnos.size(), *orig);
+ VNInfo *VNI =
+ new (VNInfoAllocator) VNInfo((unsigned)valnos.size(), *orig);
valnos.push_back(VNI);
return VNI;
}
+ /// RenumberValues - Renumber all values in order of appearance and remove
+ /// unused values.
+ /// Recalculate phi-kill flags in case any phi-def values were removed.
+ void RenumberValues(LiveIntervals &lis);
+
/// isOnlyLROfValNo - Return true if the specified live range is the only
/// one defined by the its val#.
bool isOnlyLROfValNo(const LiveRange *LR) {
}
return true;
}
-
+
/// MergeValueNumberInto - This method is called when two value nubmers
/// are found to be equivalent. This eliminates V1, replacing all
/// LiveRanges with the V1 value number with the V2 value number. This can
/// cause merging of V1/V2 values numbers and compaction of the value space.
VNInfo* MergeValueNumberInto(VNInfo *V1, VNInfo *V2);
- /// MergeInClobberRanges - For any live ranges that are not defined in the
- /// current interval, but are defined in the Clobbers interval, mark them
- /// used with an unknown definition value. Caller must pass in reference to
- /// VNInfoAllocator since it will create a new val#.
- void MergeInClobberRanges(LiveIntervals &li_,
- const LiveInterval &Clobbers,
- VNInfo::Allocator &VNInfoAllocator);
-
- /// MergeInClobberRange - Same as MergeInClobberRanges except it merge in a
- /// single LiveRange only.
- void MergeInClobberRange(LiveIntervals &li_,
- SlotIndex Start,
- SlotIndex End,
- VNInfo::Allocator &VNInfoAllocator);
-
/// MergeValueInAsValue - Merge all of the live ranges of a specific val#
/// in RHS into this live interval as the specified value number.
/// The LiveRanges in RHS are allowed to overlap with LiveRanges in the
/// except for the register of the interval.
void Copy(const LiveInterval &RHS, MachineRegisterInfo *MRI,
VNInfo::Allocator &VNInfoAllocator);
-
+
bool empty() const { return ranges.empty(); }
/// beginIndex - Return the lowest numbered slot covered by interval.
return I == end() ? 0 : &*I;
}
+ /// getVNInfoAt - Return the VNInfo that is live at Idx, or NULL.
+ VNInfo *getVNInfoAt(SlotIndex Idx) const {
+ const_iterator I = FindLiveRangeContaining(Idx);
+ return I == end() ? 0 : I->valno;
+ }
+
/// FindLiveRangeContaining - Return an iterator to the live range that
/// contains the specified index, or end() if there is none.
const_iterator FindLiveRangeContaining(SlotIndex Idx) const;
iterator FindLiveRangeContaining(SlotIndex Idx);
/// findDefinedVNInfo - Find the by the specified
- /// index (register interval) or defined
+ /// index (register interval) or defined
VNInfo *findDefinedVNInfoForRegInt(SlotIndex Idx) const;
- /// findDefinedVNInfo - Find the VNInfo that's defined by the specified
- /// register (stack inteval only).
- VNInfo *findDefinedVNInfoForStackInt(unsigned Reg) const;
-
/// overlaps - Return true if the intersection of the two live intervals is
/// not empty.
bool overlaps(const LiveInterval& other) const {
+ if (other.empty())
+ return false;
return overlapsFrom(other, other.begin());
}
///
unsigned getSize() const;
+ /// Returns true if the live interval is zero length, i.e. no live ranges
+ /// span instructions. It doesn't pay to spill such an interval.
+ bool isZeroLength() const {
+ for (const_iterator i = begin(), e = end(); i != e; ++i)
+ if (i->end.getPrevIndex() > i->start)
+ return false;
+ return true;
+ }
+
/// isSpillable - Can this interval be spilled?
bool isSpillable() const {
return weight != HUGE_VALF;
Ranges::iterator addRangeFrom(LiveRange LR, Ranges::iterator From);
void extendIntervalEndTo(Ranges::iterator I, SlotIndex NewEnd);
Ranges::iterator extendIntervalStartTo(Ranges::iterator I, SlotIndex NewStr);
+ void markValNoForDeletion(VNInfo *V);
LiveInterval& operator=(const LiveInterval& rhs); // DO NOT IMPLEMENT