llvm-6502/lib/CodeGen/RegAlloc/LiveRange.h
Ruchira Sasanka 20c82b12c9 Added support for spilling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@992 91177308-0d34-0410-b5e6-96231b3b80d8
2001-10-28 18:15:12 +00:00

194 lines
4.6 KiB
C++

/* Title: LiveRange.h
Author: Ruchira Sasanka
Date: July 25, 01
Purpose: To keep info about a live range.
Asuumptions:
Since the Value pointed by a use is the same as of its def, it is sufficient
to keep only defs in a LiveRange.
*/
#ifndef LIVE_RANGE_H
#define LIVE_RANGE_H
#include "llvm/Analysis/LiveVar/ValueSet.h"
#include "llvm/Type.h"
class RegClass;
class IGNode;
class LiveRange : public ValueSet
{
private:
RegClass *MyRegClass; // register classs (e.g., int, FP) for this LR
// a list of call instructions that interferes with this live range
//vector<const Instruction *> CallInterferenceList;
// does this live range span across calls?
// This information is used by graph
// coloring algo to avoid allocating volatile colors to live ranges
// that span across calls (since they have to be saved/restored)
bool doesSpanAcrossCalls;
IGNode *UserIGNode; // IGNode which uses this LR
int Color; // color assigned to this live range
bool mustSpill; // whether this LR must be spilt
// whether this LR must be saved accross calls ***TODO REMOVE this
bool mustSaveAcrossCalls;
// bool mustLoadFromStack; // must load from stack at start of method
int SuggestedColor; // The suggested color for this LR
// if this LR has a suggested color, can it be really alloated?
// A suggested color cannot be allocated when the suggested color is
// volatile and when there are call interferences.
bool CanUseSuggestedCol;
// if this LR is spilled, its stack offset from *FP*. The spilled offsets
// must always be relative to the FP.
int SpilledStackOffsetFromFP;
bool HasSpillOffset;
public:
~LiveRange() {} // empty destructor
void setRegClass(RegClass *const RC)
{ MyRegClass = RC; }
inline RegClass *const getRegClass() const
{ assert(MyRegClass); return MyRegClass; }
inline bool hasColor() const
{ return Color != -1; }
inline unsigned int getColor() const
{ assert( Color != -1); return (unsigned) Color ; }
inline void setColor(unsigned int Col)
{ Color = (int) Col ; }
inline void setCallInterference() {
doesSpanAcrossCalls = 1;
}
inline bool isCallInterference() const {
return (doesSpanAcrossCalls == 1);
}
inline void markForSpill() { mustSpill = true; }
inline bool isMarkedForSpill() { return mustSpill; }
inline void setSpillOffFromFP(int StackOffset) {
assert( mustSpill && "This LR is not spilled");
SpilledStackOffsetFromFP = StackOffset;
HasSpillOffset = true;
}
inline void modifySpillOffFromFP(int StackOffset) {
assert( mustSpill && "This LR is not spilled");
SpilledStackOffsetFromFP = StackOffset;
HasSpillOffset = true;
}
inline bool hasSpillOffset() {
return HasSpillOffset;
}
inline int getSpillOffFromFP() const {
assert( HasSpillOffset && "This LR is not spilled");
return SpilledStackOffsetFromFP;
}
inline void markForSaveAcrossCalls() { mustSaveAcrossCalls = true; }
// inline void markForLoadFromStack() { mustLoadFromStack = true;
inline void setUserIGNode( IGNode *const IGN)
{ assert( !UserIGNode); UserIGNode = IGN; }
inline IGNode * getUserIGNode() const
{ return UserIGNode; } // NULL if the user is not allocated
inline Type::PrimitiveID getTypeID() const {
const Value *val = *begin();
assert(val && "Can't find type - Live range is empty" );
return (val->getType())->getPrimitiveID();
}
inline void setSuggestedColor(int Col) {
//assert( (SuggestedColor == -1) && "Changing an already suggested color");
if(SuggestedColor == -1 )
SuggestedColor = Col;
else if (DEBUG_RA)
cerr << "Already has a suggested color " << Col << endl;
}
inline unsigned getSuggestedColor() const {
assert( SuggestedColor != -1); // only a valid color is obtained
return (unsigned) SuggestedColor;
}
inline bool hasSuggestedColor() const {
return ( SuggestedColor > -1);
}
inline bool isSuggestedColorUsable() const {
assert( hasSuggestedColor() && "No suggested color");
return CanUseSuggestedCol;
}
inline void setSuggestedColorUsable(const bool val) {
assert( hasSuggestedColor() && "No suggested color");
CanUseSuggestedCol = val;
}
inline LiveRange() : ValueSet() /* , CallInterferenceList() */
{
Color = SuggestedColor = -1; // not yet colored
mustSpill = mustSaveAcrossCalls = false;
MyRegClass = NULL;
UserIGNode = NULL;
doesSpanAcrossCalls = false;
CanUseSuggestedCol = true;
HasSpillOffset = false;
}
};
#endif