}
/// getCrossCopyRegClass - Returns a legal register class to copy a register
- /// in the specified class to or from. If it is possible to copy the register
- /// directly without using a cross register class copy, return the specified
- /// RC. Returns NULL if it is not possible to copy between a two registers of
- /// the specified class.
+ /// in the specified class to or from. Returns NULL if it is possible to copy
+ /// between a two registers of the specified class.
virtual const TargetRegisterClass *
getCrossCopyRegClass(const TargetRegisterClass *RC) const {
- return RC;
+ return NULL;
}
/// getRegPressureLimit - Return the register pressure "high water mark" for
TRI->getMinimalPhysRegClass(Reg, VT);
const TargetRegisterClass *DestRC = TRI->getCrossCopyRegClass(RC);
- // If cross copy register class is the same as RC, then it must be
- // possible copy the value directly. Do not try duplicate the def.
- // If cross copy register class is not the same as RC, then it's
- // possible to copy the value but it require cross register class copies
- // and it is expensive.
- // If cross copy register class is null, then it's not possible to copy
- // the value at all.
+ // If cross copy register class is null, then it must be possible copy
+ // the value directly. Do not try duplicate the def.
SUnit *NewDef = 0;
- if (DestRC != RC) {
+ if (DestRC)
NewDef = CopyAndMoveSuccessors(LRDef);
- if (!DestRC && !NewDef)
- report_fatal_error("Can't handle live physical "
- "register dependency!");
- }
+ else
+ DestRC = RC;
if (!NewDef) {
// Issue copies, these can be expensive cross register class copies.
SmallVector<SUnit*, 2> Copies;
TRI->getMinimalPhysRegClass(Reg, VT);
const TargetRegisterClass *DestRC = TRI->getCrossCopyRegClass(RC);
- // If cross copy register class is the same as RC, then it must be possible
- // copy the value directly. Do not try duplicate the def.
- // If cross copy register class is not the same as RC, then it's possible to
- // copy the value but it require cross register class copies and it is
- // expensive.
- // If cross copy register class is null, then it's not possible to copy
- // the value at all.
+ // If cross copy register class is null, then it must be possible copy
+ // the value directly. Do not try duplicate the def.
SUnit *NewDef = 0;
- if (DestRC != RC) {
+ if (DestRC)
NewDef = CopyAndMoveSuccessors(LRDef);
- if (!DestRC && !NewDef)
- report_fatal_error("Can't handle live physical register dependency!");
- }
+ else
+ DestRC = RC;
if (!NewDef) {
// Issue copies, these can be expensive cross register class copies.
SmallVector<SUnit*, 2> Copies;
else
return &X86::GR32RegClass;
}
- return RC;
+ return NULL;
}
unsigned