#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/Allocator.h"
+#include "llvm/Support/AlignOf.h"
#include <iosfwd>
#include <cassert>
#include <climits>
class TargetRegisterInfo;
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.
- /// - or reg # of the definition if it's a stack slot liveinterval.
- /// copy - Copy iff val# is defined by a copy; zero otherwise.
- /// hasPHIKill - One or more of the kills are PHI nodes.
- /// redefByEC - Re-defined by early clobber somewhere during the live range.
- /// kills - Instruction # of the kills.
- struct VNInfo {
+ /// VNInfo - Value Number Information.
+ /// 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
+ /// following rules apply:
+ ///
+ /// If the isDefAccurate() method returns false then def does not contain the
+ /// index of the defining MachineInstr, or even (necessarily) to a
+ /// MachineInstr at all. In general such a def index is not meaningful
+ /// and should not be used. The exception is that, for values originally
+ /// defined by PHI instructions, after PHI elimination def will contain the
+ /// index of the MBB in which the PHI originally existed. This can be used
+ /// to insert code (spills or copies) which deals with the value, which will
+ /// be live in to the block.
+
+ class VNInfo {
+ private:
+ enum {
+ HAS_PHI_KILL = 1,
+ REDEF_BY_EC = 1 << 1,
+ IS_PHI_DEF = 1 << 2,
+ IS_UNUSED = 1 << 3,
+ IS_DEF_ACCURATE = 1 << 4
+ };
+
+ unsigned char flags;
+
+ public:
+ /// Holds information about individual kills.
+ struct KillInfo {
+ bool isPHIKill : 1;
+ unsigned killIdx : 31;
+
+ KillInfo(bool isPHIKill, unsigned killIdx)
+ : isPHIKill(isPHIKill), killIdx(killIdx) {
+
+ assert(killIdx != 0 && "Zero kill indices are no longer permitted.");
+ }
+
+ };
+
+ typedef SmallVector<KillInfo, 4> KillSet;
+
+ /// The ID number of this value.
unsigned id;
+
+ /// The index of the defining instruction (if isDefAccurate() returns true).
unsigned def;
MachineInstr *copy;
- bool hasPHIKill : 1;
- bool redefByEC : 1;
- SmallVector<unsigned, 4> kills;
+ KillSet kills;
+
VNInfo()
- : id(~1U), def(~1U), copy(0), hasPHIKill(false), redefByEC(false) {}
+ : flags(IS_UNUSED), id(~1U), def(0), copy(0) {}
+
+ /// VNInfo constructor.
+ /// d is presumed to point to the actual defining instr. If it doesn't
+ /// setIsDefAccurate(false) should be called after construction.
VNInfo(unsigned i, unsigned d, MachineInstr *c)
- : id(i), def(d), copy(c), hasPHIKill(false), redefByEC(false) {}
+ : flags(IS_DEF_ACCURATE), id(i), def(d), copy(c) {}
+
+ /// VNInfo construtor, copies values from orig, except for the value number.
+ VNInfo(unsigned i, const VNInfo &orig)
+ : flags(orig.flags), id(i), def(orig.def), copy(orig.copy),
+ kills(orig.kills) {}
+
+ /// Used for copying value number info.
+ unsigned getFlags() const { return flags; }
+ void setFlags(unsigned flags) { this->flags = flags; }
+
+ /// Returns true if one or more kills are PHI nodes.
+ bool hasPHIKill() const { return flags & HAS_PHI_KILL; }
+ void setHasPHIKill(bool hasKill) {
+ if (hasKill)
+ flags |= HAS_PHI_KILL;
+ else
+ flags &= ~HAS_PHI_KILL;
+ }
+
+ /// Returns true if this value is re-defined by an early clobber somewhere
+ /// during the live range.
+ bool hasRedefByEC() const { return flags & REDEF_BY_EC; }
+ void setHasRedefByEC(bool hasRedef) {
+ if (hasRedef)
+ flags |= REDEF_BY_EC;
+ else
+ flags &= ~REDEF_BY_EC;
+ }
+
+ /// Returns true if this value is defined by a PHI instruction (or was,
+ /// PHI instrucions may have been eliminated).
+ bool isPHIDef() const { return flags & IS_PHI_DEF; }
+ void setIsPHIDef(bool phiDef) {
+ if (phiDef)
+ flags |= IS_PHI_DEF;
+ else
+ flags &= ~IS_PHI_DEF;
+ }
+
+ /// Returns true if this value is unused.
+ bool isUnused() const { return flags & IS_UNUSED; }
+ void setIsUnused(bool unused) {
+ if (unused)
+ flags |= IS_UNUSED;
+ else
+ flags &= ~IS_UNUSED;
+ }
+
+ /// Returns true if the def is accurate.
+ bool isDefAccurate() const { return flags & IS_DEF_ACCURATE; }
+ void setIsDefAccurate(bool defAccurate) {
+ if (defAccurate)
+ flags |= IS_DEF_ACCURATE;
+ else
+ flags &= ~IS_DEF_ACCURATE;
+ }
+
};
+ inline bool operator<(const VNInfo::KillInfo &k1, const VNInfo::KillInfo &k2) {
+ return k1.killIdx < k2.killIdx;
+ }
+
+ inline bool operator<(const VNInfo::KillInfo &k, unsigned idx) {
+ return k.killIdx < idx;
+ }
+
+ inline bool operator<(unsigned idx, const VNInfo::KillInfo &k) {
+ return idx < k.killIdx;
+ }
+
/// LiveRange structure - This represents a simple register range in the
/// program, with an inclusive start point and an exclusive end point.
/// These ranges are rendered as [start,end).
/// LiveInterval - This class represents some number of live ranges for a
/// register or value. This class also contains a bit of register allocator
/// state.
- struct LiveInterval {
+ class LiveInterval {
+ public:
+
typedef SmallVector<LiveRange,4> Ranges;
typedef SmallVector<VNInfo*,4> VNInfoList;
float weight; // weight of this interval
Ranges ranges; // the ranges in which this register is live
VNInfoList valnos; // value#'s
-
- public:
struct InstrSlots {
enum {
void copyValNumInfo(VNInfo *DstValNo, const VNInfo *SrcValNo) {
DstValNo->def = SrcValNo->def;
DstValNo->copy = SrcValNo->copy;
- DstValNo->hasPHIKill = SrcValNo->hasPHIKill;
- DstValNo->redefByEC = SrcValNo->redefByEC;
+ DstValNo->setFlags(SrcValNo->getFlags());
DstValNo->kills = SrcValNo->kills;
}
/// getNextValue - Create a new value number and return it. MIIdx specifies
/// the instruction that defines the value number.
VNInfo *getNextValue(unsigned MIIdx, MachineInstr *CopyMI,
- BumpPtrAllocator &VNInfoAllocator) {
-#ifdef __GNUC__
- unsigned Alignment = (unsigned)__alignof__(VNInfo);
-#else
- // FIXME: ugly.
- unsigned Alignment = 8;
-#endif
+ bool isDefAccurate, BumpPtrAllocator &VNInfoAllocator) {
+
+ assert(MIIdx != ~0u && MIIdx != ~1u &&
+ "PHI def / unused flags should now be passed explicitly.");
VNInfo *VNI =
static_cast<VNInfo*>(VNInfoAllocator.Allocate((unsigned)sizeof(VNInfo),
- Alignment));
+ alignof<VNInfo>()));
new (VNI) VNInfo((unsigned)valnos.size(), MIIdx, CopyMI);
+ VNI->setIsDefAccurate(isDefAccurate);
+ valnos.push_back(VNI);
+ return VNI;
+ }
+
+ /// Create a copy of the given value. The new value will be identical except
+ /// for the Value number.
+ VNInfo *createValueCopy(const VNInfo *orig, BumpPtrAllocator &VNInfoAllocator) {
+
+ VNInfo *VNI =
+ static_cast<VNInfo*>(VNInfoAllocator.Allocate((unsigned)sizeof(VNInfo),
+ alignof<VNInfo>()));
+
+ new (VNI) VNInfo((unsigned)valnos.size(), *orig);
valnos.push_back(VNI);
return VNI;
}
/// addKill - Add a kill instruction index to the specified value
/// number.
- static void addKill(VNInfo *VNI, unsigned KillIdx) {
- SmallVector<unsigned, 4> &kills = VNI->kills;
+ static void addKill(VNInfo *VNI, unsigned KillIdx, bool phiKill) {
+ VNInfo::KillSet &kills = VNI->kills;
+ VNInfo::KillInfo newKill(phiKill, KillIdx);
if (kills.empty()) {
- kills.push_back(KillIdx);
+ kills.push_back(newKill);
} else {
- SmallVector<unsigned, 4>::iterator
- I = std::lower_bound(kills.begin(), kills.end(), KillIdx);
- kills.insert(I, KillIdx);
+ VNInfo::KillSet::iterator
+ I = std::lower_bound(kills.begin(), kills.end(), newKill);
+ kills.insert(I, newKill);
}
}
/// 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) {
+ void addKills(VNInfo *VNI, const VNInfo::KillSet &kills) {
for (unsigned i = 0, e = static_cast<unsigned>(kills.size());
i != e; ++i) {
- unsigned KillIdx = kills[i];
- if (!liveBeforeAndAt(KillIdx)) {
- SmallVector<unsigned, 4>::iterator
- I = std::lower_bound(VNI->kills.begin(), VNI->kills.end(), KillIdx);
- VNI->kills.insert(I, KillIdx);
+ const VNInfo::KillInfo &Kill = kills[i];
+ if (!liveBeforeAndAt(Kill.killIdx)) {
+ VNInfo::KillSet::iterator
+ I = std::lower_bound(VNI->kills.begin(), VNI->kills.end(), Kill);
+ VNI->kills.insert(I, Kill);
}
}
}
/// 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
+ VNInfo::KillSet &kills = VNI->kills;
+ VNInfo::KillSet::iterator
I = std::lower_bound(kills.begin(), kills.end(), KillIdx);
- if (I != kills.end() && *I == KillIdx) {
+ if (I != kills.end() && I->killIdx == KillIdx) {
kills.erase(I);
return true;
}
/// removeKills - Remove all the kills in specified range
/// [Start, End] of the specified val#.
static void removeKills(VNInfo *VNI, unsigned Start, unsigned End) {
- SmallVector<unsigned, 4> &kills = VNI->kills;
- SmallVector<unsigned, 4>::iterator
+ VNInfo::KillSet &kills = VNI->kills;
+
+ VNInfo::KillSet::iterator
I = std::lower_bound(kills.begin(), kills.end(), Start);
- SmallVector<unsigned, 4>::iterator
+ VNInfo::KillSet::iterator
E = std::upper_bound(kills.begin(), kills.end(), End);
kills.erase(I, E);
}
/// isKill - Return true if the specified index is a kill of the
/// specified val#.
static bool isKill(const VNInfo *VNI, unsigned KillIdx) {
- const SmallVector<unsigned, 4> &kills = VNI->kills;
- SmallVector<unsigned, 4>::const_iterator
+ const VNInfo::KillSet &kills = VNI->kills;
+ VNInfo::KillSet::const_iterator
I = std::lower_bound(kills.begin(), kills.end(), KillIdx);
- return I != kills.end() && *I == KillIdx;
+ return I != kills.end() && I->killIdx == KillIdx;
}
/// isOnlyLROfValNo - Return true if the specified live range is the only
/// one defined by the its val#.
- bool isOnlyLROfValNo( const LiveRange *LR) {
+ bool isOnlyLROfValNo(const LiveRange *LR) {
for (const_iterator I = begin(), E = end(); I != E; ++I) {
const LiveRange *Tmp = I;
if (Tmp != LR && Tmp->valno == LR->valno)
return I == end() ? 0 : &*I;
}
+ /// getLiveRangeContaining - Return the live range that contains the
+ /// specified index, or null if there is none.
+ LiveRange *getLiveRangeContaining(unsigned Idx) {
+ iterator I = FindLiveRangeContaining(Idx);
+ return I == end() ? 0 : &*I;
+ }
+
/// 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;
void dump() const;
private:
+
Ranges::iterator addRangeFrom(LiveRange LR, Ranges::iterator From);
void extendIntervalEndTo(Ranges::iterator I, unsigned NewEnd);
Ranges::iterator extendIntervalStartTo(Ranges::iterator I, unsigned NewStr);
LiveInterval& operator=(const LiveInterval& rhs); // DO NOT IMPLEMENT
+
};
inline std::ostream &operator<<(std::ostream &OS, const LiveInterval &LI) {