#ifndef LLVM_CODEGEN_LIVEINTERVAL_H
#define LLVM_CODEGEN_LIVEINTERVAL_H
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/Allocator.h"
+#include "llvm/Support/Streams.h"
#include <iosfwd>
#include <vector>
#include <cassert>
namespace llvm {
+ class MachineInstr;
class MRegisterInfo;
+ struct LiveInterval;
+
+ /// VNInfo - If the value number definition is undefined (e.g. phi
+ /// merge point), it contains ~0u,x. If the value number is not in use, it
+ /// contains ~1u,x to indicate that the value # is not used.
+ /// def - Instruction # of the definition.
+ /// reg - Source reg iff val# is defined by a copy; zero otherwise.
+ /// kills - Instruction # of the kills. If a kill is an odd #, it means
+ /// the kill is a phi join point.
+ struct VNInfo {
+ unsigned id;
+ unsigned def;
+ unsigned reg;
+ SmallVector<unsigned, 4> kills;
+ VNInfo() : id(~1U), def(~1U), reg(0) {}
+ VNInfo(unsigned i, unsigned d, unsigned r)
+ : id(i), def(d), reg(r) {}
+ };
/// LiveRange structure - This represents a simple register range in the
/// program, with an inclusive start point and an exclusive end point.
struct LiveRange {
unsigned start; // Start point of the interval (inclusive)
unsigned end; // End point of the interval (exclusive)
- unsigned ValId; // identifier for the value contained in this interval.
+ VNInfo *valno; // identifier for the value contained in this interval.
- LiveRange(unsigned S, unsigned E, unsigned V) : start(S), end(E), ValId(V) {
+ LiveRange(unsigned S, unsigned E, VNInfo *V) : start(S), end(E), valno(V) {
assert(S < E && "Cannot create empty or backwards range");
}
}
void dump() const;
+ void print(std::ostream &os) const;
+ void print(std::ostream *os) const { if (os) print(*os); }
private:
LiveRange(); // DO NOT IMPLEMENT
};
+
std::ostream& operator<<(std::ostream& os, const LiveRange &LR);
+
inline bool operator<(unsigned V, const LiveRange &LR) {
return V < LR.start;
}
/// register or value. This class also contains a bit of register allocator
/// state.
struct LiveInterval {
- typedef std::vector<LiveRange> Ranges;
+ typedef SmallVector<LiveRange,4> Ranges;
+ typedef SmallVector<VNInfo*,4> VNInfoList;
+
unsigned reg; // the register of this interval
+ unsigned preference; // preferred register to allocate for this interval
float weight; // weight of this interval
Ranges ranges; // the ranges in which this register is live
- private:
- unsigned NumValues; // the number of distinct values in this interval.
- public:
+ VNInfoList valnos; // value#'s
+ public:
LiveInterval(unsigned Reg, float Weight)
- : reg(Reg), weight(Weight), NumValues(0) {
+ : reg(Reg), preference(0), weight(Weight) {
}
typedef Ranges::iterator iterator;
const_iterator begin() const { return ranges.begin(); }
const_iterator end() const { return ranges.end(); }
+ typedef VNInfoList::iterator vni_iterator;
+ vni_iterator vni_begin() { return valnos.begin(); }
+ vni_iterator vni_end() { return valnos.end(); }
+
+ typedef VNInfoList::const_iterator const_vni_iterator;
+ const_vni_iterator vni_begin() const { return valnos.begin(); }
+ const_vni_iterator vni_end() const { return valnos.end(); }
/// advanceTo - Advance the specified iterator to point to the LiveRange
/// containing the specified position, or end() if the position is past the
return I;
}
- void swap(LiveInterval& other) {
- std::swap(reg, other.reg);
- std::swap(weight, other.weight);
- ranges.swap(other.ranges);
- std::swap(NumValues, other.NumValues);
+ bool containsOneValue() const { return valnos.size() == 1; }
+
+ unsigned getNumValNums() const { return valnos.size(); }
+
+ /// getValNumInfo - Returns pointer to the specified val#.
+ ///
+ inline VNInfo *getValNumInfo(unsigned ValNo) {
+ return valnos[ValNo];
+ }
+ inline const VNInfo *getValNumInfo(unsigned ValNo) const {
+ return valnos[ValNo];
+ }
+
+ /// copyValNumInfo - Copy the value number info for one value number to
+ /// another.
+ void copyValNumInfo(VNInfo *DstValNo, const VNInfo *SrcValNo) {
+ DstValNo->def = SrcValNo->def;
+ DstValNo->reg = SrcValNo->reg;
+ DstValNo->kills = SrcValNo->kills;
}
- bool containsOneValue() const { return NumValues == 1; }
+ /// getNextValue - Create a new value number and return it. MIIdx specifies
+ /// the instruction that defines the value number.
+ VNInfo *getNextValue(unsigned MIIdx, unsigned SrcReg,
+ BumpPtrAllocator &VNInfoAllocator) {
+#ifdef __GNUC__
+ unsigned Alignment = __alignof__(VNInfo);
+#else
+ // FIXME: ugly.
+ unsigned Alignment = 8;
+#endif
+ VNInfo *VNI= static_cast<VNInfo*>(VNInfoAllocator.Allocate(sizeof(VNInfo),
+ Alignment));
+ new (VNI) VNInfo(valnos.size(), MIIdx, SrcReg);
+ valnos.push_back(VNI);
+ return VNI;
+ }
- unsigned getNextValue() {
- return NumValues++;
+ /// addKillForValNum - Add a kill instruction index to the specified value
+ /// number.
+ static void addKill(VNInfo *VNI, unsigned KillIdx) {
+ SmallVector<unsigned, 4> &kills = VNI->kills;
+ if (kills.empty()) {
+ kills.push_back(KillIdx);
+ } else {
+ SmallVector<unsigned, 4>::iterator
+ I = std::lower_bound(kills.begin(), kills.end(), KillIdx);
+ kills.insert(I, KillIdx);
+ }
}
+ /// addKills - Add a number of kills into the VNInfo kill vector. If this
+ /// interval is live at a kill point, then the kill is not added.
+ void addKills(VNInfo *VNI, const SmallVector<unsigned, 4> &kills) {
+ for (unsigned i = 0, e = kills.size(); i != e; ++i) {
+ unsigned KillIdx = kills[i];
+ if (!liveAt(KillIdx)) {
+ SmallVector<unsigned, 4>::iterator
+ I = std::lower_bound(VNI->kills.begin(), VNI->kills.end(), KillIdx);
+ VNI->kills.insert(I, KillIdx);
+ }
+ }
+ }
+
+ /// removeKill - Remove the specified kill from the list of kills of
+ /// the specified val#.
+ static bool removeKill(VNInfo *VNI, unsigned KillIdx) {
+ SmallVector<unsigned, 4> &kills = VNI->kills;
+ SmallVector<unsigned, 4>::iterator
+ I = std::lower_bound(kills.begin(), kills.end(), KillIdx);
+ if (I != kills.end() && *I == KillIdx) {
+ kills.erase(I);
+ return true;
+ }
+ return false;
+ }
+
+ /// removeKills - Remove all the kills in specified range
+ /// [Start, End] of the specified val#.
+ void removeKills(VNInfo *VNI, unsigned Start, unsigned End) {
+ SmallVector<unsigned, 4> &kills = VNI->kills;
+ SmallVector<unsigned, 4>::iterator
+ I = std::lower_bound(kills.begin(), kills.end(), Start);
+ SmallVector<unsigned, 4>::iterator
+ E = std::upper_bound(kills.begin(), kills.end(), End);
+ kills.erase(I, E);
+ }
+
+ /// 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.
+ void 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(const LiveInterval &Clobbers,
+ BumpPtrAllocator &VNInfoAllocator);
+
+ /// MergeRangesInAsValue - Merge all of the live ranges in RHS into this
+ /// live interval as the specified value number. The LiveRanges in RHS are
+ /// allowed to overlap with LiveRanges in the current interval, but only if
+ /// the overlapping LiveRanges have the specified value number.
+ void MergeRangesInAsValue(const LiveInterval &RHS, VNInfo *LHSValNo);
+
+ /// 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
+ /// current interval, but only if the overlapping LiveRanges have the
+ /// specified value number.
+ void MergeValueInAsValue(const LiveInterval &RHS,
+ VNInfo *RHSValNo, VNInfo *LHSValNo);
+
+ /// Copy - Copy the specified live interval. This copies all the fields
+ /// except for the register of the interval.
+ void Copy(const LiveInterval &RHS, BumpPtrAllocator &VNInfoAllocator);
+
bool empty() const { return ranges.empty(); }
/// beginNumber - Return the lowest numbered slot covered by interval.
/// getLiveRangeContaining - Return the live range that contains the
/// specified index, or null if there is none.
- const LiveRange *getLiveRangeContaining(unsigned Idx) const;
-
+ const LiveRange *getLiveRangeContaining(unsigned Idx) const {
+ const_iterator I = FindLiveRangeContaining(Idx);
+ return I == end() ? 0 : &*I;
+ }
- /// joinable - Two intervals are joinable if the either don't overlap at all
- /// or if the destination of the copy is a single assignment value, and it
- /// only overlaps with one value in the source interval.
- bool joinable(const LiveInterval& other, unsigned CopyIdx) const;
+ /// FindLiveRangeContaining - Return an iterator to the live range that
+ /// contains the specified index, or end() if there is none.
+ const_iterator FindLiveRangeContaining(unsigned Idx) const;
+ /// FindLiveRangeContaining - Return an iterator to the live range that
+ /// contains the specified index, or end() if there is none.
+ iterator FindLiveRangeContaining(unsigned Idx);
+
/// getOverlapingRanges - Given another live interval which is defined as a
/// copy from this one, return a list of all of the live ranges where the
/// two overlap and have different value numbers.
addRangeFrom(LR, ranges.begin());
}
- /// join - Join two live intervals (this, and other) together. This
- /// operation is the result of a copy instruction in the source program,
- /// that occurs at index 'CopyIdx' that copies from 'other' to 'this'. This
- /// destroys 'other'.
- void join(LiveInterval& other, unsigned CopyIdx);
-
+ /// join - Join two live intervals (this, and other) together. This applies
+ /// mappings to the value numbers in the LHS/RHS intervals as specified. If
+ /// the intervals are not joinable, this aborts.
+ void join(LiveInterval &Other, const int *ValNoAssignments,
+ const int *RHSValNoAssignments,
+ SmallVector<VNInfo*, 16> &NewVNInfo);
/// removeRange - Remove the specified range from this interval. Note that
/// the range must already be in this interval in its entirety.
void removeRange(unsigned Start, unsigned End);
+ void removeRange(LiveRange LR) {
+ removeRange(LR.start, LR.end);
+ }
+
+ /// getSize - Returns the sum of sizes of all the LiveRange's.
+ ///
+ unsigned getSize() const;
+
bool operator<(const LiveInterval& other) const {
return beginNumber() < other.beginNumber();
}
void print(std::ostream &OS, const MRegisterInfo *MRI = 0) const;
+ void print(std::ostream *OS, const MRegisterInfo *MRI = 0) const {
+ if (OS) print(*OS, MRI);
+ }
void dump() const;
private: