//===- Target/MRegisterInfo.h - Target Register Information -----*- C++ -*-===//
-//
+//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+//
//===----------------------------------------------------------------------===//
//
// This file describes an abstract interface used to get information about a
#define LLVM_TARGET_MREGISTERINFO_H
#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/ValueTypes.h"
#include <cassert>
#include <functional>
class Type;
class MachineFunction;
class MachineInstr;
-
-/// MRegisterDesc - This record contains all of the information known about a
-/// particular register. The AliasSet field (if not null) contains a pointer to
-/// a Zero terminated array of registers that this register aliases. This is
+class MachineLocation;
+class MachineMove;
+class TargetRegisterClass;
+class CalleeSavedInfo;
+class BitVector;
+
+/// TargetRegisterDesc - This record contains all of the information known about
+/// a particular register. The AliasSet field (if not null) contains a pointer
+/// to a Zero terminated array of registers that this register aliases. This is
/// needed for architectures like X86 which have AL alias AX alias EAX.
/// Registers that this does not apply to simply should set this to null.
///
-struct MRegisterDesc {
- const char *Name; // Assembly language name for the register
- const unsigned *AliasSet; // Register Alias Set, described above
- unsigned Flags; // Flags identifying register properties (below)
- unsigned TSFlags; // Target Specific Flags
+struct TargetRegisterDesc {
+ const char *Name; // Assembly language name for the register
+ const unsigned *AliasSet; // Register Alias Set, described above
};
class TargetRegisterClass {
typedef const unsigned* iterator;
typedef const unsigned* const_iterator;
+ typedef const MVT::ValueType* vt_iterator;
+ typedef const TargetRegisterClass* const * sc_iterator;
private:
+ unsigned ID;
+ bool isSubClass;
+ const vt_iterator VTs;
+ const sc_iterator SubClasses;
+ const sc_iterator SuperClasses;
const unsigned RegSize, Alignment; // Size & Alignment of register in bytes
const iterator RegsBegin, RegsEnd;
public:
- TargetRegisterClass(unsigned RS, unsigned Al, iterator RB, iterator RE)
- : RegSize(RS), Alignment(Al), RegsBegin(RB), RegsEnd(RE) {}
+ TargetRegisterClass(unsigned id,
+ const MVT::ValueType *vts,
+ const TargetRegisterClass * const *subcs,
+ const TargetRegisterClass * const *supcs,
+ unsigned RS, unsigned Al, iterator RB, iterator RE)
+ : ID(id), VTs(vts), SubClasses(subcs), SuperClasses(supcs),
+ RegSize(RS), Alignment(Al), RegsBegin(RB), RegsEnd(RE) {}
virtual ~TargetRegisterClass() {} // Allow subclasses
-
- // begin/end - Return all of the registers in this class.
+
+ /// getID() - Return the register class ID number.
+ ///
+ unsigned getID() const { return ID; }
+
+ /// begin/end - Return all of the registers in this class.
+ ///
iterator begin() const { return RegsBegin; }
iterator end() const { return RegsEnd; }
- // getNumRegs - Return the number of registers in this class
+ /// getNumRegs - Return the number of registers in this class.
+ ///
unsigned getNumRegs() const { return RegsEnd-RegsBegin; }
- // getRegister - Return the specified register in the class
+ /// getRegister - Return the specified register in the class.
+ ///
unsigned getRegister(unsigned i) const {
assert(i < getNumRegs() && "Register number out of range!");
return RegsBegin[i];
}
+ /// contains - Return true if the specified register is included in this
+ /// register class.
+ bool contains(unsigned Reg) const {
+ for (iterator I = begin(), E = end(); I != E; ++I)
+ if (*I == Reg) return true;
+ return false;
+ }
+
+ /// hasType - return true if this TargetRegisterClass has the ValueType vt.
+ ///
+ bool hasType(MVT::ValueType vt) const {
+ for(int i = 0; VTs[i] != MVT::Other; ++i)
+ if (VTs[i] == vt)
+ 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 VTs;
+ }
+
+ vt_iterator vt_end() const {
+ vt_iterator I = VTs;
+ while (*I != MVT::Other) ++I;
+ return I;
+ }
+
+ /// hasSubRegClass - return true if the specified TargetRegisterClass is a
+ /// sub-register class of this TargetRegisterClass.
+ bool hasSubRegClass(const TargetRegisterClass *cs) const {
+ for (int i = 0; SubClasses[i] != NULL; ++i)
+ if (SubClasses[i] == cs)
+ return true;
+ return false;
+ }
+
+ /// subclasses_begin / subclasses_end - Loop over all of the sub-classes of
+ /// this register class.
+ sc_iterator subclasses_begin() const {
+ return SubClasses;
+ }
+
+ sc_iterator subclasses_end() const {
+ sc_iterator I = SubClasses;
+ while (*I != NULL) ++I;
+ return I;
+ }
+
+ /// hasSuperRegClass - return true if the specified TargetRegisterClass is a
+ /// super-register class of this TargetRegisterClass.
+ bool hasSuperRegClass(const TargetRegisterClass *cs) const {
+ for (int i = 0; SuperClasses[i] != NULL; ++i)
+ if (SuperClasses[i] == cs)
+ return true;
+ return false;
+ }
+
+ /// superclasses_begin / superclasses_end - Loop over all of the super-classes
+ /// of this register class.
+ sc_iterator superclasses_begin() const {
+ return SuperClasses;
+ }
+
+ sc_iterator superclasses_end() const {
+ sc_iterator I = SuperClasses;
+ while (*I != NULL) ++I;
+ return I;
+ }
+
/// 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,
///
/// By default, these methods return all registers in the class.
///
- virtual iterator allocation_order_begin(MachineFunction &MF) const {
+ virtual iterator allocation_order_begin(const MachineFunction &MF) const {
return begin();
}
- virtual iterator allocation_order_end(MachineFunction &MF) const {
+ virtual iterator allocation_order_end(const MachineFunction &MF) const {
return end();
}
-
+
/// getSize - Return the size of the register in bytes, which is also the size
/// MRegisterInfo base class - We assume that the target defines a static array
-/// of MRegisterDesc objects that represent all of the machine registers that
-/// the target has. As such, we simply have to track a pointer to this array so
-/// that we can turn register number into a register descriptor.
+/// of TargetRegisterDesc objects that represent all of the machine registers
+/// that the target has. As such, we simply have to track a pointer to this
+/// array so that we can turn register number into a register descriptor.
///
class MRegisterInfo {
public:
typedef const TargetRegisterClass * const * regclass_iterator;
private:
- const MRegisterDesc *Desc; // Pointer to the descriptor array
+ const TargetRegisterDesc *Desc; // Pointer to the descriptor array
unsigned NumRegs; // Number of entries in the array
regclass_iterator RegClassBegin, RegClassEnd; // List of regclasses
- const TargetRegisterClass **PhysRegClasses; // Reg class for each register
int CallFrameSetupOpcode, CallFrameDestroyOpcode;
protected:
- MRegisterInfo(const MRegisterDesc *D, unsigned NR,
+ MRegisterInfo(const TargetRegisterDesc *D, unsigned NR,
regclass_iterator RegClassBegin, regclass_iterator RegClassEnd,
- int CallFrameSetupOpcode = -1, int CallFrameDestroyOpcode = -1);
+ int CallFrameSetupOpcode = -1, int CallFrameDestroyOpcode = -1);
virtual ~MRegisterInfo();
public:
enum { // Define some target independent constants
- /// NoRegister - This 'hard' register is a 'noop' register for all backends.
- /// This is used as the destination register for instructions that do not
- /// produce a value. Some frontends may use this as an operand register to
- /// mean special things, for example, the Sparc backend uses R0 to mean %g0
- /// which always PRODUCES the value 0. The X86 backend does not use this
- /// value as an operand register, except for memory references.
- ///
+ /// NoRegister - This physical register is not a real target register. It
+ /// is useful as a sentinal.
NoRegister = 0,
/// 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.
- ///
- FirstVirtualRegister = 1024,
+ FirstVirtualRegister = 1024
};
/// isPhysicalRegister - Return true if the specified register number is in
return Reg >= FirstVirtualRegister;
}
- const MRegisterDesc &operator[](unsigned RegNo) const {
+ /// getAllocatableSet - Returns a bitset indexed by register number
+ /// indicating if a register is allocatable or not.
+ BitVector getAllocatableSet(MachineFunction &MF) const;
+
+ const TargetRegisterDesc &operator[](unsigned RegNo) const {
assert(RegNo < NumRegs &&
"Attempting to access record for invalid register number!");
return Desc[RegNo];
/// Provide a get method, equivalent to [], but more useful if we have a
/// pointer to this object.
///
- const MRegisterDesc &get(unsigned RegNo) const { return operator[](RegNo); }
-
- /// getRegClass - Return the register class for the specified physical
- /// register.
- ///
- const TargetRegisterClass *getRegClass(unsigned RegNo) const {
- assert(RegNo < NumRegs && "Register number out of range!");
- assert(PhysRegClasses[RegNo] && "Register is not in a class!");
- return PhysRegClasses[RegNo];
+ const TargetRegisterDesc &get(unsigned RegNo) const {
+ return operator[](RegNo);
}
/// getAliasSet - Return the set of registers aliased by the specified
return false;
}
- virtual const unsigned* getCalleeSaveRegs() const = 0;
+ /// regsOverlap - Returns true if the two registers are equal or alias
+ /// each other. The registers may be virtual register.
+ bool regsOverlap(unsigned regA, unsigned regB) const {
+ if (regA == regB)
+ return true;
+
+ if (isVirtualRegister(regA) || isVirtualRegister(regB))
+ return false;
+ return areAliases(regA, regB);
+ }
+
+ /// getCalleeSavedRegs - Return a null-terminated list of all of the
+ /// callee saved registers on this target. The register should be in the
+ /// order of desired callee-save stack frame offset. The first register is
+ /// closed to the incoming stack pointer if stack grows down, and vice versa.
+ virtual const unsigned* getCalleeSavedRegs() const = 0;
+
+ /// getCalleeSavedRegClasses - Return a null-terminated list of the preferred
+ /// register classes to spill each callee saved register with. The order and
+ /// length of this list match the getCalleeSaveRegs() list.
+ virtual const TargetRegisterClass* const *getCalleeSavedRegClasses() const =0;
+ /// getReservedRegs - Returns a bitset indexed by physical register number
+ /// indicating if a register is a special register that has particular uses and
+ /// should be considered unavailable at all times, e.g. SP, RA. This is used by
+ /// register scavenger to determine what registers are free.
+ virtual BitVector getReservedRegs(const MachineFunction &MF) const = 0;
//===--------------------------------------------------------------------===//
// Register Class Information
unsigned getNumRegClasses() const {
return regclass_end()-regclass_begin();
}
-
- //===--------------------------------------------------------------------===//
- // All basic block modifier functions below return the number of
- // instructions added to (negative if removed from) the basic block
- // passed as their first argument.
- //
- // FIXME: This is only needed because we use a std::vector instead
- // of an ilist to keep MachineBasicBlock instructions. Inserting an
- // instruction to a MachineBasicBlock invalidates all iterators to
- // the basic block. The return value can be used to update an index
- // to the machine basic block instruction vector and circumvent the
- // iterator elimination problem but this is really not needed if we
- // move to a better representation.
- //
+
+ /// getRegClass - Returns the register class associated with the enumeration
+ /// value. See class TargetOperandInfo.
+ const TargetRegisterClass *getRegClass(unsigned i) const {
+ assert(i <= getNumRegClasses() && "Register Class ID out of range");
+ return i ? RegClassBegin[i - 1] : NULL;
+ }
//===--------------------------------------------------------------------===//
// Interfaces used by the register allocator and stack frame
// manipulation passes to move data around between registers,
- // immediates and memory. The return value is the number of
- // instructions added to (negative if removed from) the basic block.
+ // immediates and memory. FIXME: Move these to TargetInstrInfo.h.
//
- virtual int storeRegToStackSlot(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator MI,
- unsigned SrcReg, int FrameIndex,
- const TargetRegisterClass *RC) const = 0;
+ /// spillCalleeSavedRegisters - Issues instruction(s) to spill all callee saved
+ /// registers and returns true if it isn't possible / profitable to do so by
+ /// issuing a series of store instructions via storeRegToStackSlot(). Returns
+ /// false otherwise.
+ virtual bool spillCalleeSavedRegisters(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ const std::vector<CalleeSavedInfo> &CSI) const {
+ return false;
+ }
+
+ /// restoreCalleeSavedRegisters - Issues instruction(s) to restore all callee
+ /// saved registers and returns true if it isn't possible / profitable to do
+ /// so by issuing a series of load instructions via loadRegToStackSlot().
+ /// Returns false otherwise.
+ virtual bool restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ const std::vector<CalleeSavedInfo> &CSI) const {
+ return false;
+ }
- virtual int loadRegFromStackSlot(MachineBasicBlock &MBB,
+ virtual void storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
- unsigned DestReg, int FrameIndex,
+ unsigned SrcReg, int FrameIndex,
const TargetRegisterClass *RC) const = 0;
- virtual int copyRegToReg(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator MI,
- unsigned DestReg, unsigned SrcReg,
- const TargetRegisterClass *RC) const = 0;
+ virtual void loadRegFromStackSlot(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ unsigned DestReg, int FrameIndex,
+ const TargetRegisterClass *RC) const = 0;
+ virtual void copyRegToReg(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ unsigned DestReg, unsigned SrcReg,
+ const TargetRegisterClass *RC) const = 0;
/// foldMemoryOperand - Attempt to fold a load or store of the
/// specified stack slot into the specified machine instruction for
virtual MachineInstr* foldMemoryOperand(MachineInstr* MI,
unsigned OpNum,
int FrameIndex) const {
- return NULL;
+ return 0;
}
+ /// targetHandlesStackFrameRounding - Returns true if the target is responsible
+ /// for rounding up the stack frame (probably at emitPrologue time).
+ virtual bool targetHandlesStackFrameRounding() const {
+ return false;
+ }
+
+ /// requiresRegisterScavenging - returns true if the target requires (and
+ /// can make use of) the register scavenger.
+ virtual bool requiresRegisterScavenging() 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.
+ virtual bool hasFP(const MachineFunction &MF) const = 0;
+
/// getCallFrameSetup/DestroyOpcode - These methods return the opcode of the
/// frame setup/destroy instructions if they exist (-1 otherwise). Some
/// targets use pseudo instructions in order to abstract away the difference
/// instructions (but only if the Target is using them). It is responsible
/// for eliminating these instructions, replacing them with concrete
/// instructions. This method need only be implemented if using call frame
- /// setup/destroy pseudo instructions. The return value is the number of
- /// instructions added to (negative if removed from) the basic block.
+ /// setup/destroy pseudo instructions.
///
- virtual void
+ virtual void
eliminateCallFramePseudoInstr(MachineFunction &MF,
MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI) const {
assert(getCallFrameSetupOpcode()== -1 && getCallFrameDestroyOpcode()== -1 &&
- "eliminateCallFramePseudoInstr must be implemented if using"
- " call frame setup/destroy pseudo instructions!");
+ "eliminateCallFramePseudoInstr must be implemented if using"
+ " call frame setup/destroy pseudo instructions!");
assert(0 && "Call Frame Pseudo Instructions do not exist on this target!");
}
+ /// processFunctionBeforeCalleeSavedScan - This method is called immediately
+ /// before PrologEpilogInserter scans the physical registers used to determine
+ /// what callee saved registers should be spilled. This method is optional.
+ virtual void processFunctionBeforeCalleeSavedScan(MachineFunction &MF) const {
+ }
+
/// processFunctionBeforeFrameFinalized - This method is called immediately
/// before the specified functions frame layout (MF.getFrameInfo()) is
/// finalized. Once the frame is finalized, MO_FrameIndex operands are
- /// replaced with direct constants. This method is optional. The return value
- /// is the number of instructions added to (negative if removed from) the
- /// basic block
+ /// replaced with direct constants. This method is optional.
///
virtual void processFunctionBeforeFrameFinalized(MachineFunction &MF) const {
}
/// finished product. The return value is the number of instructions
/// added to (negative if removed from) the basic block.
///
- virtual void eliminateFrameIndex(MachineFunction &MF,
- MachineBasicBlock::iterator MI) const = 0;
+ virtual void eliminateFrameIndex(MachineBasicBlock::iterator MI) const = 0;
/// emitProlog/emitEpilog - These methods insert prolog and epilog code into
/// the function. The return value is the number of instructions
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.
+ virtual int getDwarfRegNum(unsigned RegNum) const = 0;
+
+ /// 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;
+
+ /// getRARegister - This method should return the register where the return
+ /// address can be found.
+ virtual unsigned getRARegister() const = 0;
+
+ /// getLocation - This method should return the actual location of a frame
+ /// variable given the frame index. The location is returned in ML.
+ /// Subclasses should override this method for special handling of frame
+ /// variables and call MRegisterInfo::getLocation for the default action.
+ virtual void getLocation(MachineFunction &MF, unsigned Index,
+ MachineLocation &ML) const;
+
+ /// 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.)
+ virtual void getInitialFrameState(std::vector<MachineMove> &Moves) const;
};
-// This is useful when building DenseMaps keyed on virtual registers
+// This is useful when building IndexedMaps keyed on virtual registers
struct VirtReg2IndexFunctor : std::unary_function<unsigned, unsigned> {
unsigned operator()(unsigned Reg) const {
return Reg - MRegisterInfo::FirstVirtualRegister;