//
// This file implements the LiveRange and LiveInterval classes. Given some
// numbering of each the machine instructions an interval [i, j) is said to be a
-// live interval for register v if there is no instruction with number j' > j
+// live interval for register v if there is no instruction with number j' >= j
// such that v is live at j' and there is no instruction with number i' < i such
// that v is live at i'. In this implementation intervals can have holes,
// i.e. an interval might look like [1,20), [50,65), [1000,1001). Each
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/Allocator.h"
-#include "llvm/Support/Streams.h"
#include <iosfwd>
-#include <vector>
#include <cassert>
namespace llvm {
/// 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.
+ /// - 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.
- /// kills - Instruction # of the kills. If a kill is an odd #, it means
- /// the kill is a phi join point.
+ /// redefByEC - Re-defined by early clobber somewhere during the live range.
+ /// kills - Instruction # of the kills.
struct VNInfo {
unsigned id;
unsigned def;
- unsigned reg;
- bool hasPHIKill;
+ MachineInstr *copy;
+ bool hasPHIKill : 1;
+ bool redefByEC : 1;
SmallVector<unsigned, 4> kills;
- VNInfo() : id(~1U), def(~1U), reg(0), hasPHIKill(false) {}
- VNInfo(unsigned i, unsigned d, unsigned r)
- : id(i), def(d), reg(r), hasPHIKill(false) {}
+ VNInfo()
+ : id(~1U), def(~1U), copy(0), hasPHIKill(false), redefByEC(false) {}
+ VNInfo(unsigned i, unsigned d, MachineInstr *c)
+ : id(i), def(d), copy(c), hasPHIKill(false), redefByEC(false) {}
};
/// LiveRange structure - This represents a simple register range in the
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
+ unsigned reg; // the register or stack slot of this interval
+ // if the top bits is set, it represents a stack slot.
float weight; // weight of this interval
+ unsigned short preference; // preferred register for this interval
Ranges ranges; // the ranges in which this register is live
VNInfoList valnos; // value#'s
public:
- LiveInterval(unsigned Reg, float Weight)
- : reg(Reg), preference(0), weight(Weight) {
+ LiveInterval(unsigned Reg, float Weight, bool IsSS = false)
+ : reg(Reg), weight(Weight), preference(0) {
+ if (IsSS)
+ reg = reg | (1U << (sizeof(unsigned)*8-1));
}
typedef Ranges::iterator iterator;
return I;
}
+ /// isStackSlot - Return true if this is a stack slot interval.
+ ///
+ bool isStackSlot() const {
+ return reg & (1U << (sizeof(unsigned)*8-1));
+ }
+
+ /// getStackSlotIndex - Return stack slot index if this is a stack slot
+ /// interval.
+ int getStackSlotIndex() const {
+ assert(isStackSlot() && "Interval is not a stack slot interval!");
+ return reg & ~(1U << (sizeof(unsigned)*8-1));
+ }
+
+ bool hasAtLeastOneValue() const { return !valnos.empty(); }
+
bool containsOneValue() const { return valnos.size() == 1; }
- unsigned getNumValNums() const { return valnos.size(); }
+ unsigned getNumValNums() const { return (unsigned)valnos.size(); }
/// getValNumInfo - Returns pointer to the specified val#.
///
/// another.
void copyValNumInfo(VNInfo *DstValNo, const VNInfo *SrcValNo) {
DstValNo->def = SrcValNo->def;
- DstValNo->reg = SrcValNo->reg;
+ DstValNo->copy = SrcValNo->copy;
DstValNo->hasPHIKill = SrcValNo->hasPHIKill;
+ DstValNo->redefByEC = SrcValNo->redefByEC;
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, unsigned SrcReg,
+ VNInfo *getNextValue(unsigned MIIdx, MachineInstr *CopyMI,
BumpPtrAllocator &VNInfoAllocator) {
#ifdef __GNUC__
- unsigned Alignment = __alignof__(VNInfo);
+ unsigned Alignment = (unsigned)__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);
+ VNInfo *VNI =
+ static_cast<VNInfo*>(VNInfoAllocator.Allocate((unsigned)sizeof(VNInfo),
+ Alignment));
+ new (VNI) VNInfo((unsigned)valnos.size(), MIIdx, CopyMI);
valnos.push_back(VNI);
return VNI;
}
- /// addKillForValNum - Add a kill instruction index to the specified value
+ /// addKill - Add a kill instruction index to the specified value
/// number.
static void addKill(VNInfo *VNI, unsigned KillIdx) {
SmallVector<unsigned, 4> &kills = VNI->kills;
/// 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) {
+ for (unsigned i = 0, e = static_cast<unsigned>(kills.size());
+ i != e; ++i) {
unsigned KillIdx = kills[i];
- if (!liveAt(KillIdx)) {
+ if (!liveBeforeAndAt(KillIdx)) {
SmallVector<unsigned, 4>::iterator
I = std::lower_bound(VNI->kills.begin(), VNI->kills.end(), KillIdx);
VNI->kills.insert(I, KillIdx);
/// removeKills - Remove all the kills in specified range
/// [Start, End] of the specified val#.
- void removeKills(VNInfo *VNI, unsigned Start, unsigned End) {
+ static 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);
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
+ I = std::lower_bound(kills.begin(), kills.end(), KillIdx);
+ return I != kills.end() && *I == KillIdx;
+ }
/// MergeValueNumberInto - This method is called when two value nubmers
/// are found to be equivalent. This eliminates V1, replacing all
/// 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;
}
bool liveAt(unsigned index) const;
+ // liveBeforeAndAt - Check if the interval is live at the index and the
+ // index just before it. If index is liveAt, check if it starts a new live
+ // range.If it does, then check if the previous live range ends at index-1.
+ bool liveBeforeAndAt(unsigned index) const;
+
/// getLiveRangeContaining - Return the live range that contains the
/// specified index, or null if there is none.
const LiveRange *getLiveRangeContaining(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);
+
+ /// findDefinedVNInfo - Find the VNInfo that's defined at the specified
+ /// index (register interval) or defined by the specified register (stack
+ /// inteval).
+ VNInfo *findDefinedVNInfo(unsigned DefIdxOrReg) const;
/// overlaps - Return true if the intersection of the two live intervals is
/// not empty.
/// the intervals are not joinable, this aborts.
void join(LiveInterval &Other, const int *ValNoAssignments,
const int *RHSValNoAssignments,
- SmallVector<VNInfo*, 16> &NewVNInfo);
+ 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.
projects / oota-llvm.git / blobdiff