/// isASubClass - return true if this TargetRegisterClass is a subset
/// class of at least one other TargetRegisterClass.
bool isASubClass() const {
- return SuperClasses[0] != 0;
+ return SuperClasses[0] != nullptr;
}
/// getRawAllocationOrder - Returns the preferred order for allocating
const unsigned *SubRegIndexLaneMasks;
regclass_iterator RegClassBegin, RegClassEnd; // List of regclasses
+ unsigned CoveringLanes;
protected:
TargetRegisterInfo(const TargetRegisterInfoDesc *ID,
regclass_iterator RegClassBegin,
regclass_iterator RegClassEnd,
const char *const *SRINames,
- const unsigned *SRILaneMasks);
+ const unsigned *SRILaneMasks,
+ unsigned CoveringLanes);
virtual ~TargetRegisterInfo();
public:
/// indicating if a register is allocatable or not. If a register class is
/// specified, returns the subset for the class.
BitVector getAllocatableSet(const MachineFunction &MF,
- const TargetRegisterClass *RC = NULL) const;
+ const TargetRegisterClass *RC = nullptr) const;
/// getCostPerUse - Return the additional cost of using this register instead
/// of other registers in its class.
return SubRegIndexLaneMasks[SubIdx];
}
+ /// The lane masks returned by getSubRegIndexLaneMask() above can only be
+ /// used to determine if sub-registers overlap - they can't be used to
+ /// determine if a set of sub-registers completely cover another
+ /// sub-register.
+ ///
+ /// The X86 general purpose registers have two lanes corresponding to the
+ /// sub_8bit and sub_8bit_hi sub-registers. Both sub_32bit and sub_16bit have
+ /// lane masks '3', but the sub_16bit sub-register doesn't fully cover the
+ /// sub_32bit sub-register.
+ ///
+ /// On the other hand, the ARM NEON lanes fully cover their registers: The
+ /// dsub_0 sub-register is completely covered by the ssub_0 and ssub_1 lanes.
+ /// This is related to the CoveredBySubRegs property on register definitions.
+ ///
+ /// This function returns a bit mask of lanes that completely cover their
+ /// sub-registers. More precisely, given:
+ ///
+ /// Covering = getCoveringLanes();
+ /// MaskA = getSubRegIndexLaneMask(SubA);
+ /// MaskB = getSubRegIndexLaneMask(SubB);
+ ///
+ /// If (MaskA & ~(MaskB & Covering)) == 0, then SubA is completely covered by
+ /// SubB.
+ unsigned getCoveringLanes() const { return CoveringLanes; }
+
/// 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 {
/// order of desired callee-save stack frame offset. The first register is
/// closest to the incoming stack pointer if stack grows down, and vice versa.
///
- virtual const MCPhysReg* getCalleeSavedRegs(const MachineFunction *MF = 0)
- const = 0;
+ virtual const MCPhysReg*
+ getCalleeSavedRegs(const MachineFunction *MF = nullptr) const = 0;
/// getCallPreservedMask - Return a mask of call-preserved registers for the
/// given calling convention on the current sub-target. The mask should
///
virtual const uint32_t *getCallPreservedMask(CallingConv::ID) const {
// The default mask clobbers everything. All targets should override.
- return 0;
+ return nullptr;
}
/// getReservedRegs - Returns a bitset indexed by physical register number
ArrayRef<MCPhysReg> Order,
SmallVectorImpl<MCPhysReg> &Hints,
const MachineFunction &MF,
- const VirtRegMap *VRM = 0) const;
+ const VirtRegMap *VRM = nullptr) const;
/// avoidWriteAfterWrite - Return true if the register allocator should avoid
/// writing a register from RC in two consecutive instructions.
// Do nothing.
}
+ /// Allow the target to reverse allocation order of local live ranges. This
+ /// will generally allocate shorter local live ranges first. For targets with
+ /// many registers, this could reduce regalloc compile time by a large
+ /// factor. It is disabled by default for three reasons:
+ /// (1) Top-down allocation is simpler and easier to debug for targets that
+ /// don't benefit from reversing the order.
+ /// (2) Bottom-up allocation could result in poor evicition decisions on some
+ /// targets affecting the performance of compiled code.
+ /// (3) Bottom-up allocation is no longer guaranteed to optimally color.
+ virtual bool reverseLocalAssignment() const { return false; }
+
+ /// Allow the target to override register assignment heuristics based on the
+ /// live range size. If this returns false, then local live ranges are always
+ /// assigned in order regardless of their size. This is a temporary hook for
+ /// debugging downstream codegen failures exposed by regalloc.
+ virtual bool mayOverrideLocalAssignment() const { return true; }
+
+ /// Allow the target to override the cost of using a callee-saved register for
+ /// the first time. Default value of 0 means we will use a callee-saved
+ /// register if it is available.
+ virtual unsigned getCSRFirstUseCost() const { return 0; }
+
/// requiresRegisterScavenging - returns true if the target requires (and can
/// make use of) the register scavenger.
virtual bool requiresRegisterScavenging(const MachineFunction &MF) const {
/// resolveFrameIndex - Resolve a frame index operand of an instruction
/// to reference the indicated base register plus offset instead.
- virtual void resolveFrameIndex(MachineBasicBlock::iterator I,
- unsigned BaseReg, int64_t Offset) const {
+ virtual void resolveFrameIndex(MachineInstr &MI, unsigned BaseReg,
+ int64_t Offset) const {
llvm_unreachable("resolveFrameIndex does not exist on this target");
}
llvm_unreachable("isFrameOffsetLegal does not exist on this target");
}
- /// eliminateCallFramePseudoInstr - This method is called during prolog/epilog
- /// code insertion to eliminate call frame setup and destroy pseudo
- /// 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.
- ///
- virtual void
- eliminateCallFramePseudoInstr(MachineFunction &MF,
- MachineBasicBlock &MBB,
- MachineBasicBlock::iterator MI) const {
- llvm_unreachable("Call Frame Pseudo Instructions do not exist on this "
- "target!");
- }
-
/// saveScavengerRegister - Spill the register so it can be used by the
/// register scavenger. Return true if the register was spilled, false
/// 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 at the
- /// finished product. SPAdj is the SP adjustment due to call frame setup
- /// instruction.
+ /// finished product. SPAdj is the SP adjustment due to call frame setup
+ /// instruction. FIOperandNum is the FI operand number.
virtual void eliminateFrameIndex(MachineBasicBlock::iterator MI,
- int SPAdj, RegScavenger *RS=NULL) const = 0;
+ int SPAdj, unsigned FIOperandNum,
+ RegScavenger *RS = nullptr) const = 0;
+
+ //===--------------------------------------------------------------------===//
+ /// Subtarget Hooks
+
+ /// \brief SrcRC and DstRC will be morphed into NewRC if this returns true.
+ virtual bool shouldCoalesce(MachineInstr *MI,
+ const TargetRegisterClass *SrcRC,
+ unsigned SubReg,
+ const TargetRegisterClass *DstRC,
+ unsigned DstSubReg,
+ const TargetRegisterClass *NewRC) const
+ { return true; }
//===--------------------------------------------------------------------===//
/// Debug information queries.
/// getFrameRegister - This method should return the register used as a base
/// for values allocated in the current stack frame.
virtual unsigned getFrameRegister(const MachineFunction &MF) const = 0;
-
- /// getCompactUnwindRegNum - This function maps the register to the number for
- /// compact unwind encoding. Return -1 if the register isn't valid.
- virtual int getCompactUnwindRegNum(unsigned, bool) const {
- return -1;
- }
};
Mask += RCMaskWords;
SubReg = *Idx++;
if (!SubReg)
- Idx = 0;
+ Idx = nullptr;
}
};
unsigned Reg;
unsigned SubIdx;
public:
- explicit PrintReg(unsigned reg, const TargetRegisterInfo *tri = 0,
+ explicit PrintReg(unsigned reg, const TargetRegisterInfo *tri = nullptr,
unsigned subidx = 0)
: TRI(tri), Reg(reg), SubIdx(subidx) {}
void print(raw_ostream&) const;
/// Usage: OS << PrintRegUnit(Unit, TRI) << '\n';
///
class PrintRegUnit {
+protected:
const TargetRegisterInfo *TRI;
unsigned Unit;
public:
return OS;
}
+/// PrintVRegOrUnit - It is often convenient to track virtual registers and
+/// physical register units in the same list.
+class PrintVRegOrUnit : protected PrintRegUnit {
+public:
+ PrintVRegOrUnit(unsigned VRegOrUnit, const TargetRegisterInfo *tri)
+ : PrintRegUnit(VRegOrUnit, tri) {}
+ void print(raw_ostream&) const;
+};
+
+static inline raw_ostream &operator<<(raw_ostream &OS,
+ const PrintVRegOrUnit &PR) {
+ PR.print(OS);
+ return OS;
+}
+
} // End llvm namespace
#endif
projects / oota-llvm.git / blobdiff