/// of AX.
///
struct TargetRegisterDesc {
- const char *AsmName; // Assembly language name for the register
const char *Name; // Printable name for the reg (for debugging)
const unsigned *AliasSet; // Register Alias Set, described above
const unsigned *SubRegs; // Sub-register set, described above
RegSet.insert(*I);
}
virtual ~TargetRegisterClass() {} // Allow subclasses
-
+
/// getID() - Return the register class ID number.
///
unsigned getID() const { return ID; }
}
/// contains - Return true if the specified register is included in this
- /// register class.
+ /// register class. This does not include virtual registers.
bool contains(unsigned Reg) const {
return RegSet.count(Reg);
}
return true;
return false;
}
-
+
/// vt_begin / vt_end - Loop over all of the value types that can be
/// represented by values in this register class.
vt_iterator vt_begin() const {
return I;
}
- /// hasSubClass - return true if the the specified TargetRegisterClass
+ /// hasSubClass - return true if the specified TargetRegisterClass
/// is a proper subset of this TargetRegisterClass.
bool hasSubClass(const TargetRegisterClass *cs) const {
- for (int i = 0; SubClasses[i] != NULL; ++i)
+ for (int i = 0; SubClasses[i] != NULL; ++i)
if (SubClasses[i] == cs)
return true;
return false;
sc_iterator subclasses_begin() const {
return SubClasses;
}
-
+
sc_iterator subclasses_end() const {
sc_iterator I = SubClasses;
while (*I != NULL) ++I;
return I;
}
-
+
/// hasSuperClass - return true if the specified TargetRegisterClass is a
/// proper superset of this TargetRegisterClass.
bool hasSuperClass(const TargetRegisterClass *cs) const {
- for (int i = 0; SuperClasses[i] != NULL; ++i)
+ for (int i = 0; SuperClasses[i] != NULL; ++i)
if (SuperClasses[i] == cs)
return true;
return false;
sc_iterator superclasses_begin() const {
return SuperClasses;
}
-
+
sc_iterator superclasses_end() const {
sc_iterator I = SuperClasses;
while (*I != NULL) ++I;
bool isASubClass() const {
return SuperClasses[0] != 0;
}
-
+
/// allocation_order_begin/end - These methods define a range of registers
/// which specify the registers in this class that are valid to register
/// allocate, and the preferred order to allocate them in. For example,
regclass_iterator RegClassBegin, RegClassEnd; // List of regclasses
int CallFrameSetupOpcode, CallFrameDestroyOpcode;
+
protected:
TargetRegisterInfo(const TargetRegisterDesc *D, unsigned NR,
regclass_iterator RegClassBegin,
/// FirstVirtualRegister - This is the first register number that is
/// considered to be a 'virtual' register, which is part of the SSA
/// namespace. This must be the same for all targets, which means that each
- /// target is limited to 1024 registers.
+ /// target is limited to this fixed number of registers.
FirstVirtualRegister = 1024
};
/// getAllocatableSet - Returns a bitset indexed by register number
/// indicating if a register is allocatable or not. If a register class is
/// specified, returns the subset for the class.
- BitVector getAllocatableSet(MachineFunction &MF,
+ BitVector getAllocatableSet(const MachineFunction &MF,
const TargetRegisterClass *RC = NULL) const;
const TargetRegisterDesc &operator[](unsigned RegNo) const {
SubregHash[index*2+1] != 0) {
if (SubregHash[index*2] == regA && SubregHash[index*2+1] == regB)
return true;
-
+
index = (index + ProbeAmt) & (SubregHashSize-1);
ProbeAmt += 2;
}
-
+
return false;
}
SuperregHash[index*2+1] != 0) {
if (SuperregHash[index*2] == regA && SuperregHash[index*2+1] == regB)
return true;
-
+
index = (index + ProbeAmt) & (SuperregHashSize-1);
ProbeAmt += 2;
}
-
+
return false;
}
/// exist.
virtual unsigned getSubReg(unsigned RegNo, unsigned Index) const = 0;
+ /// getSubRegIndex - For a given register pair, return the sub-register index
+ /// if the are second register is a sub-register of the first. Return zero
+ /// otherwise.
+ virtual unsigned getSubRegIndex(unsigned RegNo, unsigned SubRegNo) const = 0;
+
/// getMatchingSuperReg - Return a super-register of the specified register
/// Reg so its sub-register of index SubIdx is Reg.
- unsigned getMatchingSuperReg(unsigned Reg, unsigned SubIdx,
+ unsigned getMatchingSuperReg(unsigned Reg, unsigned SubIdx,
const TargetRegisterClass *RC) const {
for (const unsigned *SRs = getSuperRegisters(Reg); unsigned SR = *SRs;++SRs)
if (Reg == getSubReg(SR, SubIdx) && RC->contains(SR))
unsigned getNumRegClasses() const {
return (unsigned)(regclass_end()-regclass_begin());
}
-
+
/// getRegClass - Returns the register class associated with the enumeration
/// value. See class TargetOperandInfo.
const TargetRegisterClass *getRegClass(unsigned i) const {
virtual bool requiresRegisterScavenging(const MachineFunction &MF) const {
return false;
}
-
+
+ /// requiresFrameIndexScavenging - returns true if the target requires post
+ /// PEI scavenging of registers for materializing frame index constants.
+ virtual bool requiresFrameIndexScavenging(const MachineFunction &MF) const {
+ return false;
+ }
+
/// hasFP - Return true if the specified function should have a dedicated
/// frame pointer register. For most targets this is true only if the function
/// has variable sized allocas or if frame pointer elimination is disabled.
return !hasFP(MF);
}
+ /// canSimplifyCallFramePseudos - When possible, it's best to simplify the
+ /// call frame pseudo ops before doing frame index elimination. This is
+ /// possible only when frame index references between the pseudos won't
+ /// need adjusted for the call frame adjustments. Normally, that's true
+ /// if the function has a reserved call frame or a frame pointer. Some
+ /// targets (Thumb2, for example) may have more complicated criteria,
+ /// however, and can override this behavior.
+ virtual bool canSimplifyCallFramePseudos(MachineFunction &MF) const {
+ return hasReservedCallFrame(MF) || hasFP(MF);
+ }
+
/// hasReservedSpillSlot - Return true if target has reserved a spill slot in
/// the stack frame of the given function for the specified register. e.g. On
/// x86, if the frame register is required, the first fixed stack object is
virtual void processFunctionBeforeFrameFinalized(MachineFunction &MF) const {
}
+ /// saveScavengerRegister - Spill the register so it can be used by the
+ /// register scavenger. Return true if the register was spilled, false
+ /// otherwise. If this function does not spill the register, the scavenger
+ /// will instead spill it to the emergency spill slot.
+ ///
+ virtual bool saveScavengerRegister(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator I,
+ MachineBasicBlock::iterator &UseMI,
+ const TargetRegisterClass *RC,
+ unsigned Reg) const {
+ return false;
+ }
+
/// eliminateFrameIndex - This method must be overriden to eliminate abstract
/// frame indices from instructions which may use them. The instruction
/// referenced by the iterator contains an MO_FrameIndex operand which must be
/// eliminated by this method. This method may modify or replace the
- /// specified instruction, as long as it keeps the iterator pointing the the
+ /// specified instruction, as long as it keeps the iterator pointing at the
/// finished product. SPAdj is the SP adjustment due to call frame setup
/// instruction.
- virtual void eliminateFrameIndex(MachineBasicBlock::iterator MI,
- int SPAdj, RegScavenger *RS=NULL) const = 0;
+ ///
+ /// When -enable-frame-index-scavenging is enabled, the virtual register
+ /// allocated for this frame index is returned and its value is stored in
+ /// *Value.
+ typedef std::pair<unsigned, int> FrameIndexValue;
+ virtual unsigned eliminateFrameIndex(MachineBasicBlock::iterator MI,
+ int SPAdj, FrameIndexValue *Value = NULL,
+ RegScavenger *RS=NULL) const = 0;
/// emitProlog/emitEpilog - These methods insert prolog and epilog code into
/// the function.
virtual void emitPrologue(MachineFunction &MF) const = 0;
virtual void emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const = 0;
-
+
//===--------------------------------------------------------------------===//
/// Debug information queries.
-
+
/// getDwarfRegNum - Map a target register to an equivalent dwarf register
/// number. Returns -1 if there is no equivalent value. The second
/// parameter allows targets to use different numberings for EH info and
/// getFrameRegister - This method should return the register used as a base
/// for values allocated in the current stack frame.
- virtual unsigned getFrameRegister(MachineFunction &MF) const = 0;
+ virtual unsigned getFrameRegister(const MachineFunction &MF) const = 0;
/// getFrameIndexOffset - Returns the displacement from the frame register to
/// the stack frame of the specified index.
- virtual int getFrameIndexOffset(MachineFunction &MF, int FI) const;
-
+ virtual int getFrameIndexOffset(const MachineFunction &MF, int FI) const;
+
+ /// getFrameIndexReference - This method should return the base register
+ /// and offset used to reference a frame index location. The offset is
+ /// returned directly, and the base register is returned via FrameReg.
+ virtual int getFrameIndexReference(const MachineFunction &MF, int FI,
+ unsigned &FrameReg) const {
+ // By default, assume all frame indices are referenced via whatever
+ // getFrameRegister() says. The target can override this if it's doing
+ // something different.
+ FrameReg = getFrameRegister(MF);
+ return getFrameIndexOffset(MF, FI);
+ }
+
/// getRARegister - This method should return the register where the return
/// address can be found.
virtual unsigned getRARegister() const = 0;
-
+
/// getInitialFrameState - Returns a list of machine moves that are assumed
/// on entry to all functions. Note that LabelID is ignored (assumed to be
/// the beginning of the function.)
projects / oota-llvm.git / blobdiff