X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FTarget%2FTargetRegisterInfo.h;h=9c171379f306f46221908906110d392fb940e595;hb=a5babc8a31efd3bd40e6deec96d0ee1cb14e61eb;hp=cdc35908066666aa8263b181ee6e3d188df41811;hpb=8ca9a862038e8c4e9a2ca73b3b75e1be3425155f;p=oota-llvm.git diff --git a/include/llvm/Target/TargetRegisterInfo.h b/include/llvm/Target/TargetRegisterInfo.h index cdc35908066..9c171379f30 100644 --- a/include/llvm/Target/TargetRegisterInfo.h +++ b/include/llvm/Target/TargetRegisterInfo.h @@ -16,11 +16,11 @@ #ifndef LLVM_TARGET_TARGETREGISTERINFO_H #define LLVM_TARGET_TARGETREGISTERINFO_H -#include "llvm/MC/MCRegisterInfo.h" -#include "llvm/CodeGen/MachineBasicBlock.h" -#include "llvm/CodeGen/ValueTypes.h" #include "llvm/ADT/ArrayRef.h" -#include "llvm/ADT/DenseSet.h" +#include "llvm/CodeGen/MachineBasicBlock.h" +#include "llvm/CodeGen/MachineValueType.h" +#include "llvm/IR/CallingConv.h" +#include "llvm/MC/MCRegisterInfo.h" #include #include @@ -30,39 +30,76 @@ class BitVector; class MachineFunction; class RegScavenger; template class SmallVectorImpl; +class VirtRegMap; class raw_ostream; -class TargetRegisterClass : public MCRegisterClass { +class TargetRegisterClass { public: - typedef const EVT* vt_iterator; + typedef const MCPhysReg* iterator; + typedef const MCPhysReg* const_iterator; + typedef const MVT::SimpleValueType* vt_iterator; typedef const TargetRegisterClass* const * sc_iterator; -private: + + // Instance variables filled by tablegen, do not use! + const MCRegisterClass *MC; const vt_iterator VTs; - const sc_iterator SubClasses; + const uint32_t *SubClassMask; + const uint16_t *SuperRegIndices; const sc_iterator SuperClasses; - const sc_iterator SubRegClasses; - const sc_iterator SuperRegClasses; -public: - TargetRegisterClass(unsigned id, const char *name, const EVT *vts, - const TargetRegisterClass * const *subcs, - const TargetRegisterClass * const *supcs, - const TargetRegisterClass * const *subregcs, - const TargetRegisterClass * const *superregcs, - unsigned RS, unsigned Al, int CC, bool Allocable, - iterator RB, iterator RE) - : MCRegisterClass(id, name, RS, Al, CC, Allocable, RB, RE), - VTs(vts), SubClasses(subcs), SuperClasses(supcs), SubRegClasses(subregcs), - SuperRegClasses(superregcs) { - initMCRegisterClass(); + ArrayRef (*OrderFunc)(const MachineFunction&); + + /// getID() - Return the register class ID number. + /// + unsigned getID() const { return MC->getID(); } + + /// begin/end - Return all of the registers in this class. + /// + iterator begin() const { return MC->begin(); } + iterator end() const { return MC->end(); } + + /// getNumRegs - Return the number of registers in this class. + /// + unsigned getNumRegs() const { return MC->getNumRegs(); } + + /// getRegister - Return the specified register in the class. + /// + unsigned getRegister(unsigned i) const { + return MC->getRegister(i); + } + + /// contains - Return true if the specified register is included in this + /// register class. This does not include virtual registers. + bool contains(unsigned Reg) const { + return MC->contains(Reg); } - virtual ~TargetRegisterClass() {} // Allow subclasses + /// contains - Return true if both registers are in this class. + bool contains(unsigned Reg1, unsigned Reg2) const { + return MC->contains(Reg1, Reg2); + } + + /// getSize - Return the size of the register in bytes, which is also the size + /// of a stack slot allocated to hold a spilled copy of this register. + unsigned getSize() const { return MC->getSize(); } + + /// getAlignment - Return the minimum required alignment for a register of + /// this class. + unsigned getAlignment() const { return MC->getAlignment(); } + + /// getCopyCost - Return the cost of copying a value between two registers in + /// this class. A negative number means the register class is very expensive + /// to copy e.g. status flag register classes. + int getCopyCost() const { return MC->getCopyCost(); } + + /// isAllocatable - Return true if this register class may be used to create + /// virtual registers. + bool isAllocatable() const { return MC->isAllocatable(); } /// hasType - return true if this TargetRegisterClass has the ValueType vt. /// - bool hasType(EVT vt) const { + bool hasType(MVT vt) const { for(int i = 0; VTs[i] != MVT::Other; ++i) - if (VTs[i] == vt) + if (MVT(VTs[i]) == vt) return true; return false; } @@ -79,95 +116,61 @@ public: return I; } - /// subregclasses_begin / subregclasses_end - Loop over all of - /// the subreg register classes of this register class. - sc_iterator subregclasses_begin() const { - return SubRegClasses; - } - - sc_iterator subregclasses_end() const { - sc_iterator I = SubRegClasses; - while (*I != NULL) ++I; - return I; - } - - /// getSubRegisterRegClass - Return the register class of subregisters with - /// index SubIdx, or NULL if no such class exists. - const TargetRegisterClass* getSubRegisterRegClass(unsigned SubIdx) const { - assert(SubIdx>0 && "Invalid subregister index"); - return SubRegClasses[SubIdx-1]; - } - - /// superregclasses_begin / superregclasses_end - Loop over all of - /// the superreg register classes of this register class. - sc_iterator superregclasses_begin() const { - return SuperRegClasses; - } - - sc_iterator superregclasses_end() const { - sc_iterator I = SuperRegClasses; - while (*I != NULL) ++I; - return I; - } - /// 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) - if (SubClasses[i] == cs) - return true; - return false; + /// is a proper sub-class of this TargetRegisterClass. + bool hasSubClass(const TargetRegisterClass *RC) const { + return RC != this && hasSubClassEq(RC); } - /// hasSubClassEq - Returns true if RC is a subclass of or equal to this + /// hasSubClassEq - Returns true if RC is a sub-class of or equal to this /// class. bool hasSubClassEq(const TargetRegisterClass *RC) const { - return RC == this || hasSubClass(RC); - } - - /// subclasses_begin / subclasses_end - Loop over all of the classes - /// that are proper subsets 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; + unsigned ID = RC->getID(); + return (SubClassMask[ID / 32] >> (ID % 32)) & 1; } /// 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) - if (SuperClasses[i] == cs) - return true; - return false; + /// proper super-class of this TargetRegisterClass. + bool hasSuperClass(const TargetRegisterClass *RC) const { + return RC->hasSubClass(this); } - /// hasSuperClassEq - Returns true if RC is a superclass of or equal to this + /// hasSuperClassEq - Returns true if RC is a super-class of or equal to this /// class. bool hasSuperClassEq(const TargetRegisterClass *RC) const { - return RC == this || hasSuperClass(RC); + return RC->hasSubClassEq(this); } - /// superclasses_begin / superclasses_end - Loop over all of the classes - /// that are proper supersets of this register class. - sc_iterator superclasses_begin() const { - return SuperClasses; + /// getSubClassMask - Returns a bit vector of subclasses, including this one. + /// The vector is indexed by class IDs, see hasSubClassEq() above for how to + /// use it. + const uint32_t *getSubClassMask() const { + return SubClassMask; } - sc_iterator superclasses_end() const { - sc_iterator I = SuperClasses; - while (*I != NULL) ++I; - return I; + /// getSuperRegIndices - Returns a 0-terminated list of sub-register indices + /// that project some super-register class into this register class. The list + /// has an entry for each Idx such that: + /// + /// There exists SuperRC where: + /// For all Reg in SuperRC: + /// this->contains(Reg:Idx) + /// + const uint16_t *getSuperRegIndices() const { + return SuperRegIndices; + } + + /// getSuperClasses - Returns a NULL terminated list of super-classes. The + /// classes are ordered by ID which is also a topological ordering from large + /// to small classes. The list does NOT include the current class. + sc_iterator getSuperClasses() const { + return SuperClasses; } /// 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 @@ -184,9 +187,8 @@ public: /// /// By default, this method returns all registers in the class. /// - virtual - ArrayRef getRawAllocationOrder(const MachineFunction &MF) const { - return makeArrayRef(begin(), getNumRegs()); + ArrayRef getRawAllocationOrder(const MachineFunction &MF) const { + return OrderFunc ? OrderFunc(MF) : makeArrayRef(begin(), getNumRegs()); } }; @@ -197,6 +199,13 @@ struct TargetRegisterInfoDesc { bool inAllocatableClass; // Register belongs to an allocatable regclass. }; +/// Each TargetRegisterClass has a per register weight, and weight +/// limit which must be less than the limits of its pressure sets. +struct RegClassWeight { + unsigned RegWeight; + unsigned WeightLimit; +}; + /// TargetRegisterInfo base class - We assume that the target defines a static /// array of TargetRegisterDesc objects that represent all of the machine /// registers that the target has. As such, we simply have to track a pointer @@ -209,13 +218,19 @@ public: private: const TargetRegisterInfoDesc *InfoDesc; // Extra desc array for codegen const char *const *SubRegIndexNames; // Names of subreg indexes. + // Pointer to array of lane masks, one per sub-reg index. + 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 *subregindexnames); + const char *const *SRINames, + const unsigned *SRILaneMasks, + unsigned CoveringLanes); virtual ~TargetRegisterInfo(); public: @@ -287,13 +302,18 @@ public: /// register of the given type, picking the most sub register class of /// the right type that contains this physreg. const TargetRegisterClass * - getMinimalPhysRegClass(unsigned Reg, EVT VT = MVT::Other) const; + getMinimalPhysRegClass(unsigned Reg, MVT VT = MVT::Other) const; + + /// getAllocatableClass - Return the maximal subclass of the given register + /// class that is alloctable, or NULL. + const TargetRegisterClass * + getAllocatableClass(const TargetRegisterClass *RC) const; /// 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(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. @@ -310,44 +330,117 @@ public: /// getSubRegIndexName - Return the human-readable symbolic target-specific /// name for the specified SubRegIndex. const char *getSubRegIndexName(unsigned SubIdx) const { - assert(SubIdx && "This is not a subregister index"); + assert(SubIdx && SubIdx < getNumSubRegIndices() && + "This is not a subregister index"); return SubRegIndexNames[SubIdx-1]; } + /// getSubRegIndexLaneMask - Return a bitmask representing the parts of a + /// register that are covered by SubIdx. + /// + /// Lane masks for sub-register indices are similar to register units for + /// physical registers. The individual bits in a lane mask can't be assigned + /// any specific meaning. They can be used to check if two sub-register + /// indices overlap. + /// + /// If the target has a register such that: + /// + /// getSubReg(Reg, A) overlaps getSubReg(Reg, B) + /// + /// then: + /// + /// getSubRegIndexLaneMask(A) & getSubRegIndexLaneMask(B) != 0 + /// + /// The converse is not necessarily true. If two lane masks have a common + /// bit, the corresponding sub-registers may not overlap, but it can be + /// assumed that they usually will. + unsigned getSubRegIndexLaneMask(unsigned SubIdx) const { + // SubIdx == 0 is allowed, it has the lane mask ~0u. + assert(SubIdx < getNumSubRegIndices() && "This is not a subregister index"); + 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 { if (regA == regB) return true; if (isVirtualRegister(regA) || isVirtualRegister(regB)) return false; - for (const unsigned *regList = getOverlaps(regA)+1; *regList; ++regList) { - if (*regList == regB) return true; - } - return false; - } - /// isSubRegister - Returns true if regB is a sub-register of regA. - /// - bool isSubRegister(unsigned regA, unsigned regB) const { - return isSuperRegister(regB, regA); + // Regunits are numerically ordered. Find a common unit. + MCRegUnitIterator RUA(regA, this); + MCRegUnitIterator RUB(regB, this); + do { + if (*RUA == *RUB) return true; + if (*RUA < *RUB) ++RUA; + else ++RUB; + } while (RUA.isValid() && RUB.isValid()); + return false; } - /// isSuperRegister - Returns true if regB is a super-register of regA. - /// - bool isSuperRegister(unsigned regA, unsigned regB) const { - for (const unsigned *regList = getSuperRegisters(regA); *regList;++regList){ - if (*regList == regB) return true; - } + /// hasRegUnit - Returns true if Reg contains RegUnit. + bool hasRegUnit(unsigned Reg, unsigned RegUnit) const { + for (MCRegUnitIterator Units(Reg, this); Units.isValid(); ++Units) + if (*Units == RegUnit) + return true; return false; } /// 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 MachineFunction *MF = 0) - const = 0; + /// closest to the incoming stack pointer if stack grows down, and vice versa. + /// + 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 + /// include all call-preserved aliases. This is used by the register + /// allocator to determine which registers can be live across a call. + /// + /// The mask is an array containing (TRI::getNumRegs()+31)/32 entries. + /// A set bit indicates that all bits of the corresponding register are + /// preserved across the function call. The bit mask is expected to be + /// sub-register complete, i.e. if A is preserved, so are all its + /// sub-registers. + /// + /// Bits are numbered from the LSB, so the bit for physical register Reg can + /// be found as (Mask[Reg / 32] >> Reg % 32) & 1. + /// + /// A NULL pointer means that no register mask will be used, and call + /// instructions should use implicit-def operands to indicate call clobbered + /// registers. + /// + virtual const uint32_t *getCallPreservedMask(CallingConv::ID) const { + // The default mask clobbers everything. All targets should override. + return nullptr; + } /// getReservedRegs - Returns a bitset indexed by physical register number /// indicating if a register is a special register that has particular uses @@ -355,50 +448,45 @@ public: /// used by register scavenger to determine what registers are free. virtual BitVector getReservedRegs(const MachineFunction &MF) const = 0; - /// getSubReg - Returns the physical register number of sub-register "Index" - /// for physical register RegNo. Return zero if the sub-register does not - /// exist. - virtual unsigned getSubReg(unsigned RegNo, unsigned Index) const = 0; - - /// getSubRegIndex - For a given register pair, return the sub-register index - /// if the 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, const TargetRegisterClass *RC) const { - for (const unsigned *SRs = getSuperRegisters(Reg); unsigned SR = *SRs;++SRs) - if (Reg == getSubReg(SR, SubIdx) && RC->contains(SR)) - return SR; - return 0; - } - - /// canCombineSubRegIndices - Given a register class and a list of - /// subregister indices, return true if it's possible to combine the - /// subregister indices into one that corresponds to a larger - /// subregister. Return the new subregister index by reference. Note the - /// new index may be zero if the given subregisters can be combined to - /// form the whole register. - virtual bool canCombineSubRegIndices(const TargetRegisterClass *RC, - SmallVectorImpl &SubIndices, - unsigned &NewSubIdx) const { - return 0; + return MCRegisterInfo::getMatchingSuperReg(Reg, SubIdx, RC->MC); } /// getMatchingSuperRegClass - Return a subclass of the specified register /// class A so that each register in it has a sub-register of the /// specified sub-register index which is in the specified register class B. + /// + /// TableGen will synthesize missing A sub-classes. virtual const TargetRegisterClass * getMatchingSuperRegClass(const TargetRegisterClass *A, - const TargetRegisterClass *B, unsigned Idx) const { - return 0; + const TargetRegisterClass *B, unsigned Idx) const; + + /// getSubClassWithSubReg - Returns the largest legal sub-class of RC that + /// supports the sub-register index Idx. + /// If no such sub-class exists, return NULL. + /// If all registers in RC already have an Idx sub-register, return RC. + /// + /// TableGen generates a version of this function that is good enough in most + /// cases. Targets can override if they have constraints that TableGen + /// doesn't understand. For example, the x86 sub_8bit sub-register index is + /// supported by the full GR32 register class in 64-bit mode, but only by the + /// GR32_ABCD regiister class in 32-bit mode. + /// + /// TableGen will synthesize missing RC sub-classes. + virtual const TargetRegisterClass * + getSubClassWithSubReg(const TargetRegisterClass *RC, unsigned Idx) const { + assert(Idx == 0 && "Target has no sub-registers"); + return RC; } /// composeSubRegIndices - Return the subregister index you get from composing /// two subregister indices. /// + /// The special null sub-register index composes as the identity. + /// /// If R:a:b is the same register as R:c, then composeSubRegIndices(a, b) /// returns c. Note that composeSubRegIndices does not tell you about illegal /// compositions. If R does not have a subreg a, or R:a does not have a subreg @@ -408,11 +496,47 @@ public: /// ssub_0:S0 - ssub_3:S3 subregs. /// If you compose subreg indices dsub_1, ssub_0 you get ssub_2. /// - virtual unsigned composeSubRegIndices(unsigned a, unsigned b) const { - // This default implementation is correct for most targets. - return b; + unsigned composeSubRegIndices(unsigned a, unsigned b) const { + if (!a) return b; + if (!b) return a; + return composeSubRegIndicesImpl(a, b); } +protected: + /// Overridden by TableGen in targets that have sub-registers. + virtual unsigned composeSubRegIndicesImpl(unsigned, unsigned) const { + llvm_unreachable("Target has no sub-registers"); + } + +public: + /// getCommonSuperRegClass - Find a common super-register class if it exists. + /// + /// Find a register class, SuperRC and two sub-register indices, PreA and + /// PreB, such that: + /// + /// 1. PreA + SubA == PreB + SubB (using composeSubRegIndices()), and + /// + /// 2. For all Reg in SuperRC: Reg:PreA in RCA and Reg:PreB in RCB, and + /// + /// 3. SuperRC->getSize() >= max(RCA->getSize(), RCB->getSize()). + /// + /// SuperRC will be chosen such that no super-class of SuperRC satisfies the + /// requirements, and there is no register class with a smaller spill size + /// that satisfies the requirements. + /// + /// SubA and SubB must not be 0. Use getMatchingSuperRegClass() instead. + /// + /// Either of the PreA and PreB sub-register indices may be returned as 0. In + /// that case, the returned register class will be a sub-class of the + /// corresponding argument register class. + /// + /// The function returns NULL if no register class can be found. + /// + const TargetRegisterClass* + getCommonSuperRegClass(const TargetRegisterClass *RCA, unsigned SubA, + const TargetRegisterClass *RCB, unsigned SubB, + unsigned &PreA, unsigned &PreB) const; + //===--------------------------------------------------------------------===// // Register Class Information // @@ -433,12 +557,23 @@ public: return RegClassBegin[i]; } + /// getRegClassName - Returns the name of the register class. + const char *getRegClassName(const TargetRegisterClass *Class) const { + return MCRegisterInfo::getRegClassName(Class->MC); + } + + /// getCommonSubClass - find the largest common subclass of A and B. Return + /// NULL if there is no common subclass. + const TargetRegisterClass * + getCommonSubClass(const TargetRegisterClass *A, + const TargetRegisterClass *B) const; + /// getPointerRegClass - Returns a TargetRegisterClass used for pointer /// values. If a target supports multiple different pointer register classes, /// kind specifies which one is indicated. - virtual const TargetRegisterClass *getPointerRegClass(unsigned Kind=0) const { - assert(0 && "Target didn't implement getPointerRegClass!"); - return 0; // Must return a value in order to compile with VS 2005 + virtual const TargetRegisterClass * + getPointerRegClass(const MachineFunction &MF, unsigned Kind=0) const { + llvm_unreachable("Target didn't implement getPointerRegClass!"); } /// getCrossCopyRegClass - Returns a legal register class to copy a register @@ -465,32 +600,59 @@ public: /// getRegPressureLimit - Return the register pressure "high water mark" for /// the specific register class. The scheduler is in high register pressure /// mode (for the specific register class) if it goes over the limit. + /// + /// Note: this is the old register pressure model that relies on a manually + /// specified representative register class per value type. virtual unsigned getRegPressureLimit(const TargetRegisterClass *RC, MachineFunction &MF) const { return 0; } - /// getRawAllocationOrder - Returns the register allocation order for a - /// specified register class with a target-dependent hint. The returned list - /// may contain reserved registers that cannot be allocated. - /// - /// Register allocators need only call this function to resolve - /// target-dependent hints, but it should work without hinting as well. - virtual ArrayRef - getRawAllocationOrder(const TargetRegisterClass *RC, - unsigned HintType, unsigned HintReg, - const MachineFunction &MF) const { - return RC->getRawAllocationOrder(MF); - } + /// Get the weight in units of pressure for this register class. + virtual const RegClassWeight &getRegClassWeight( + const TargetRegisterClass *RC) const = 0; - /// ResolveRegAllocHint - Resolves the specified register allocation hint - /// to a physical register. Returns the physical register if it is successful. - virtual unsigned ResolveRegAllocHint(unsigned Type, unsigned Reg, - const MachineFunction &MF) const { - if (Type == 0 && Reg && isPhysicalRegister(Reg)) - return Reg; - return 0; - } + /// Get the weight in units of pressure for this register unit. + virtual unsigned getRegUnitWeight(unsigned RegUnit) const = 0; + + /// Get the number of dimensions of register pressure. + virtual unsigned getNumRegPressureSets() const = 0; + + /// Get the name of this register unit pressure set. + virtual const char *getRegPressureSetName(unsigned Idx) const = 0; + + /// Get the register unit pressure limit for this dimension. + /// This limit must be adjusted dynamically for reserved registers. + virtual unsigned getRegPressureSetLimit(unsigned Idx) const = 0; + + /// Get the dimensions of register pressure impacted by this register class. + /// Returns a -1 terminated array of pressure set IDs. + virtual const int *getRegClassPressureSets( + const TargetRegisterClass *RC) const = 0; + + /// Get the dimensions of register pressure impacted by this register unit. + /// Returns a -1 terminated array of pressure set IDs. + virtual const int *getRegUnitPressureSets(unsigned RegUnit) const = 0; + + /// Get a list of 'hint' registers that the register allocator should try + /// first when allocating a physical register for the virtual register + /// VirtReg. These registers are effectively moved to the front of the + /// allocation order. + /// + /// The Order argument is the allocation order for VirtReg's register class + /// as returned from RegisterClassInfo::getOrder(). The hint registers must + /// come from Order, and they must not be reserved. + /// + /// The default implementation of this function can resolve + /// target-independent hints provided to MRI::setRegAllocationHint with + /// HintType == 0. Targets that override this function should defer to the + /// default implementation if they have no reason to change the allocation + /// order for VirtReg. There may be target-independent hints. + virtual void getRegAllocationHints(unsigned VirtReg, + ArrayRef Order, + SmallVectorImpl &Hints, + const MachineFunction &MF, + const VirtRegMap *VRM = nullptr) const; /// avoidWriteAfterWrite - Return true if the register allocator should avoid /// writing a register from RC in two consecutive instructions. @@ -511,6 +673,22 @@ public: // 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 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 { @@ -548,6 +726,12 @@ public: return false; } + /// trackLivenessAfterRegAlloc - returns true if the live-ins should be tracked + /// after register allocation. + virtual bool trackLivenessAfterRegAlloc(const MachineFunction &MF) const { + return false; + } + /// needsStackRealignment - true if storage within the function requires the /// stack pointer to be aligned more than the normal calling convention calls /// for. @@ -575,36 +759,22 @@ public: virtual void materializeFrameBaseRegister(MachineBasicBlock *MBB, unsigned BaseReg, int FrameIdx, int64_t Offset) const { - assert(0 && "materializeFrameBaseRegister does not exist on this target"); + llvm_unreachable("materializeFrameBaseRegister does not exist on this " + "target"); } /// 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 { - assert(0 && "resolveFrameIndex does not exist on this target"); + virtual void resolveFrameIndex(MachineInstr &MI, unsigned BaseReg, + int64_t Offset) const { + llvm_unreachable("resolveFrameIndex does not exist on this target"); } /// isFrameOffsetLegal - Determine whether a given offset immediate is /// encodable to resolve a frame index. virtual bool isFrameOffsetLegal(const MachineInstr *MI, int64_t Offset) const { - assert(0 && "isFrameOffsetLegal does not exist on this target"); - return false; // Must return a value in order to compile with VS 2005 - } - - /// 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 { - assert(0 && "Call Frame Pseudo Instructions do not exist on this target!"); + llvm_unreachable("isFrameOffsetLegal does not exist on this target"); } @@ -626,10 +796,23 @@ public: /// 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. @@ -637,15 +820,65 @@ public: /// 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; +//===----------------------------------------------------------------------===// +// SuperRegClassIterator +//===----------------------------------------------------------------------===// +// +// Iterate over the possible super-registers for a given register class. The +// iterator will visit a list of pairs (Idx, Mask) corresponding to the +// possible classes of super-registers. +// +// Each bit mask will have at least one set bit, and each set bit in Mask +// corresponds to a SuperRC such that: +// +// For all Reg in SuperRC: Reg:Idx is in RC. +// +// The iterator can include (O, RC->getSubClassMask()) as the first entry which +// also satisfies the above requirement, assuming Reg:0 == Reg. +// +class SuperRegClassIterator { + const unsigned RCMaskWords; + unsigned SubReg; + const uint16_t *Idx; + const uint32_t *Mask; + +public: + /// Create a SuperRegClassIterator that visits all the super-register classes + /// of RC. When IncludeSelf is set, also include the (0, sub-classes) entry. + SuperRegClassIterator(const TargetRegisterClass *RC, + const TargetRegisterInfo *TRI, + bool IncludeSelf = false) + : RCMaskWords((TRI->getNumRegClasses() + 31) / 32), + SubReg(0), + Idx(RC->getSuperRegIndices()), + Mask(RC->getSubClassMask()) { + if (!IncludeSelf) + ++*this; + } + + /// Returns true if this iterator is still pointing at a valid entry. + bool isValid() const { return Idx; } + + /// Returns the current sub-register index. + unsigned getSubReg() const { return SubReg; } + + /// Returns the bit mask if register classes that getSubReg() projects into + /// RC. + const uint32_t *getMask() const { return Mask; } + + /// Advance iterator to the next entry. + void operator++() { + assert(isValid() && "Cannot move iterator past end."); + Mask += RCMaskWords; + SubReg = *Idx++; + if (!SubReg) + Idx = nullptr; } }; - // This is useful when building IndexedMaps keyed on virtual registers struct VirtReg2IndexFunctor : public std::unary_function { unsigned operator()(unsigned Reg) const { @@ -653,11 +886,6 @@ struct VirtReg2IndexFunctor : public std::unary_function { } }; -/// getCommonSubClass - find the largest common subclass of A and B. Return NULL -/// if there is no common subclass. -const TargetRegisterClass *getCommonSubClass(const TargetRegisterClass *A, - const TargetRegisterClass *B); - /// PrintReg - Helper class for printing registers on a raw_ostream. /// Prints virtual and physical registers with or without a TRI instance. /// @@ -675,7 +903,8 @@ class PrintReg { unsigned Reg; unsigned SubIdx; public: - PrintReg(unsigned reg, const TargetRegisterInfo *tri = 0, unsigned subidx = 0) + explicit PrintReg(unsigned reg, const TargetRegisterInfo *tri = nullptr, + unsigned subidx = 0) : TRI(tri), Reg(reg), SubIdx(subidx) {} void print(raw_ostream&) const; }; @@ -685,6 +914,45 @@ static inline raw_ostream &operator<<(raw_ostream &OS, const PrintReg &PR) { return OS; } +/// PrintRegUnit - Helper class for printing register units on a raw_ostream. +/// +/// Register units are named after their root registers: +/// +/// AL - Single root. +/// FP0~ST7 - Dual roots. +/// +/// Usage: OS << PrintRegUnit(Unit, TRI) << '\n'; +/// +class PrintRegUnit { +protected: + const TargetRegisterInfo *TRI; + unsigned Unit; +public: + PrintRegUnit(unsigned unit, const TargetRegisterInfo *tri) + : TRI(tri), Unit(unit) {} + void print(raw_ostream&) const; +}; + +static inline raw_ostream &operator<<(raw_ostream &OS, const PrintRegUnit &PR) { + PR.print(OS); + 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