//
//===----------------------------------------------------------------------===//
//
-// This file describes the target machine instructions to the code generator.
+// This file describes the target machine instruction set to the code generator.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TARGET_TARGETINSTRINFO_H
#define LLVM_TARGET_TARGETINSTRINFO_H
-#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/MC/MCInstrInfo.h"
+#include "llvm/CodeGen/DFAPacketizer.h"
#include "llvm/CodeGen/MachineFunction.h"
-#include "llvm/Support/DataTypes.h"
-#include <vector>
-#include <cassert>
namespace llvm {
-class MachineInstr;
-class TargetMachine;
-class TargetRegisterClass;
+class InstrItineraryData;
class LiveVariables;
-class CalleeSavedInfo;
+class MCAsmInfo;
+class MachineMemOperand;
+class MachineRegisterInfo;
+class MDNode;
+class MCInst;
+class MCSchedModel;
class SDNode;
+class ScheduleHazardRecognizer;
class SelectionDAG;
+class ScheduleDAG;
+class TargetRegisterClass;
+class TargetRegisterInfo;
+class BranchProbability;
template<class T> class SmallVectorImpl;
-//===----------------------------------------------------------------------===//
-// Data types used to define information about a single machine instruction
-//===----------------------------------------------------------------------===//
-
-typedef short MachineOpCode;
-
-//===----------------------------------------------------------------------===//
-// struct TargetInstrDescriptor:
-// Predefined information about each machine instruction.
-// Designed to initialized statically.
-//
-
-const unsigned M_BRANCH_FLAG = 1 << 0;
-const unsigned M_CALL_FLAG = 1 << 1;
-const unsigned M_RET_FLAG = 1 << 2;
-const unsigned M_BARRIER_FLAG = 1 << 3;
-const unsigned M_DELAY_SLOT_FLAG = 1 << 4;
-
-/// M_SIMPLE_LOAD_FLAG - This flag is set for instructions that are simple loads
-/// from memory. This should only be set on instructions that load a value from
-/// memory and return it in their only virtual register definition.
-const unsigned M_SIMPLE_LOAD_FLAG = 1 << 5;
-
-/// M_MAY_STORE_FLAG - This flag is set to any instruction that could possibly
-/// modify memory. Instructions with this flag set are not necessarily simple
-/// store instructions, they may store a modified value based on their operands,
-/// or may not actually modify anything, for example.
-const unsigned M_MAY_STORE_FLAG = 1 << 6;
-
-const unsigned M_INDIRECT_FLAG = 1 << 7;
-const unsigned M_IMPLICIT_DEF_FLAG = 1 << 8;
-
-// M_CONVERTIBLE_TO_3_ADDR - This is a 2-address instruction which can be
-// changed into a 3-address instruction if the first two operands cannot be
-// assigned to the same register. The target must implement the
-// TargetInstrInfo::convertToThreeAddress method for this instruction.
-const unsigned M_CONVERTIBLE_TO_3_ADDR = 1 << 9;
-
-// This M_COMMUTABLE - is a 2- or 3-address instruction (of the form X = op Y,
-// Z), which produces the same result if Y and Z are exchanged.
-const unsigned M_COMMUTABLE = 1 << 10;
-
-// M_TERMINATOR_FLAG - Is this instruction part of the terminator for a basic
-// block? Typically this is things like return and branch instructions.
-// Various passes use this to insert code into the bottom of a basic block, but
-// before control flow occurs.
-const unsigned M_TERMINATOR_FLAG = 1 << 11;
-
-// M_USES_CUSTOM_DAG_SCHED_INSERTION - Set if this instruction requires custom
-// insertion support when the DAG scheduler is inserting it into a machine basic
-// block.
-const unsigned M_USES_CUSTOM_DAG_SCHED_INSERTION = 1 << 12;
-
-// M_VARIABLE_OPS - Set if this instruction can have a variable number of extra
-// operands in addition to the minimum number operands specified.
-const unsigned M_VARIABLE_OPS = 1 << 13;
-
-// M_PREDICABLE - Set if this instruction has a predicate operand that
-// controls execution. It may be set to 'always'.
-const unsigned M_PREDICABLE = 1 << 14;
-
-// M_REMATERIALIZIBLE - Set if this instruction can be trivally re-materialized
-// at any time, e.g. constant generation, load from constant pool.
-const unsigned M_REMATERIALIZIBLE = 1 << 15;
-
-// M_NOT_DUPLICABLE - Set if this instruction cannot be safely duplicated.
-// (e.g. instructions with unique labels attached).
-const unsigned M_NOT_DUPLICABLE = 1 << 16;
-
-// M_HAS_OPTIONAL_DEF - Set if this instruction has an optional definition, e.g.
-// ARM instructions which can set condition code if 's' bit is set.
-const unsigned M_HAS_OPTIONAL_DEF = 1 << 17;
-
-// M_NEVER_HAS_SIDE_EFFECTS - Set if this instruction has no side effects that
-// are not captured by any operands of the instruction or other flags, and when
-// *all* instances of the instruction of that opcode have no side effects.
-//
-// Note: This and M_MAY_HAVE_SIDE_EFFECTS are mutually exclusive. You can't set
-// both! If neither flag is set, then the instruction *always* has side effects.
-const unsigned M_NEVER_HAS_SIDE_EFFECTS = 1 << 18;
-
-// M_MAY_HAVE_SIDE_EFFECTS - Set if some instances of this instruction can have
-// side effects. The virtual method "isReallySideEffectFree" is called to
-// determine this. Load instructions are an example of where this is useful. In
-// general, loads always have side effects. However, loads from constant pools
-// don't. We let the specific back end make this determination.
-//
-// Note: This and M_NEVER_HAS_SIDE_EFFECTS are mutually exclusive. You can't set
-// both! If neither flag is set, then the instruction *always* has side effects.
-const unsigned M_MAY_HAVE_SIDE_EFFECTS = 1 << 19;
-
-
-//===----------------------------------------------------------------------===//
-// Machine operand flags
-//===----------------------------------------------------------------------===//
-
-namespace TOI {
- // Operand constraints: only "tied_to" for now.
- enum OperandConstraint {
- TIED_TO = 0 // Must be allocated the same register as.
- };
-
- /// OperandFlags - These are flags set on operands, but should be considered
- /// private, all access should go through the TargetOperandInfo accessors.
- /// See the accessors for a description of what these are.
- enum OperandFlags {
- LookupPtrRegClass = 1 << 0,
- Predicate = 1 << 1,
- OptionalDef = 1 << 2
- };
-}
-
-/// TargetOperandInfo - This holds information about one operand of a machine
-/// instruction, indicating the register class for register operands, etc.
-///
-class TargetOperandInfo {
-public:
- /// RegClass - This specifies the register class enumeration of the operand
- /// if the operand is a register. If not, this contains 0.
- unsigned short RegClass;
- unsigned short Flags;
- /// Lower 16 bits are used to specify which constraints are set. The higher 16
- /// bits are used to specify the value of constraints (4 bits each).
- unsigned int Constraints;
- /// Currently no other information.
-
- /// isLookupPtrRegClass - Set if this operand is a pointer value and it
- /// requires a callback to look up its register class.
- bool isLookupPtrRegClass() const { return Flags & TOI::LookupPtrRegClass; }
-
- /// isPredicate - Set if this is one of the operands that made up of
- /// the predicate operand that controls an M_PREDICATED instruction.
- bool isPredicate() const { return Flags & TOI::Predicate; }
-
- /// isOptionalDef - Set if this operand is a optional def.
- ///
- bool isOptionalDef() const { return Flags & TOI::OptionalDef; }
-};
-
-
-class TargetInstrDescriptor {
-public:
- unsigned short Opcode; // The opcode.
- unsigned short numOperands; // Num of args (may be more if variable_ops).
- unsigned short numDefs; // Num of args that are definitions.
- const char * Name; // Assembly language mnemonic for the opcode.
- unsigned SchedClass; // enum identifying instr sched class
- unsigned Flags; // flags identifying machine instr class
- unsigned TSFlags; // Target Specific Flag values
- const unsigned *ImplicitUses; // Registers implicitly read by this instr
- const unsigned *ImplicitDefs; // Registers implicitly defined by this instr
- const TargetOperandInfo *OpInfo; // 'numOperands' entries about operands.
-
- /// getOperandConstraint - Returns the value of the specific constraint if
- /// it is set. Returns -1 if it is not set.
- int getOperandConstraint(unsigned OpNum,
- TOI::OperandConstraint Constraint) const {
- assert((OpNum < numOperands || (Flags & M_VARIABLE_OPS)) &&
- "Invalid operand # of TargetInstrInfo");
- if (OpNum < numOperands &&
- (OpInfo[OpNum].Constraints & (1 << Constraint))) {
- unsigned Pos = 16 + Constraint * 4;
- return (int)(OpInfo[OpNum].Constraints >> Pos) & 0xf;
- }
- return -1;
- }
-
- /// findTiedToSrcOperand - Returns the operand that is tied to the specified
- /// dest operand. Returns -1 if there isn't one.
- int findTiedToSrcOperand(unsigned OpNum) const;
-
- bool isCall() const {
- return Flags & M_CALL_FLAG;
- }
-
- bool isBranch() const {
- return Flags & M_BRANCH_FLAG;
- }
-
- bool isTerminator() const {
- return Flags & M_TERMINATOR_FLAG;
- }
-
- bool isIndirectBranch() const {
- return Flags & M_INDIRECT_FLAG;
- }
-
- bool isPredicable() const {
- return Flags & M_PREDICABLE;
- }
-
- bool isNotDuplicable() const {
- return Flags & M_NOT_DUPLICABLE;
- }
-
-
-
- /// isSimpleLoad - Return true for instructions that are simple loads from
- /// memory. This should only be set on instructions that load a value from
- /// memory and return it in their only virtual register definition.
- /// Instructions that return a value loaded from memory and then modified in
- /// some way should not return true for this.
- bool isSimpleLoad() const {
- return Flags & M_SIMPLE_LOAD_FLAG;
- }
-
- /// mayStore - Return true if this instruction could possibly modify memory.
- /// Instructions with this flag set are not necessarily simple store
- /// instructions, they may store a modified value based on their operands, or
- /// may not actually modify anything, for example.
- bool mayStore() const {
- return Flags & M_MAY_STORE_FLAG;
- }
-
- /// isBarrier - Returns true if the specified instruction stops control flow
- /// from executing the instruction immediately following it. Examples include
- /// unconditional branches and return instructions.
- bool isBarrier() const {
- return Flags & M_BARRIER_FLAG;
- }
-
- /// hasDelaySlot - Returns true if the specified instruction has a delay slot
- /// which must be filled by the code generator.
- bool hasDelaySlot() const {
- return Flags & M_DELAY_SLOT_FLAG;
- }
-
- unsigned getSchedClass() const {
- return SchedClass;
- }
-};
-
//---------------------------------------------------------------------------
///
-/// TargetInstrInfo - Interface to description of machine instructions
+/// TargetInstrInfo - Interface to description of machine instruction set
///
-class TargetInstrInfo {
- const TargetInstrDescriptor* desc; // raw array to allow static init'n
- unsigned NumOpcodes; // number of entries in the desc array
- unsigned numRealOpCodes; // number of non-dummy op codes
-
- TargetInstrInfo(const TargetInstrInfo &); // DO NOT IMPLEMENT
- void operator=(const TargetInstrInfo &); // DO NOT IMPLEMENT
+class TargetInstrInfo : public MCInstrInfo {
+ TargetInstrInfo(const TargetInstrInfo &) LLVM_DELETED_FUNCTION;
+ void operator=(const TargetInstrInfo &) LLVM_DELETED_FUNCTION;
public:
- TargetInstrInfo(const TargetInstrDescriptor *desc, unsigned NumOpcodes);
- virtual ~TargetInstrInfo();
-
- // Invariant opcodes: All instruction sets have these as their low opcodes.
- enum {
- PHI = 0,
- INLINEASM = 1,
- LABEL = 2,
- EXTRACT_SUBREG = 3,
- INSERT_SUBREG = 4
- };
-
- unsigned getNumOpcodes() const { return NumOpcodes; }
-
- /// get - Return the machine instruction descriptor that corresponds to the
- /// specified instruction opcode.
- ///
- const TargetInstrDescriptor& get(unsigned Opcode) const {
- assert(Opcode < NumOpcodes);
- return desc[Opcode];
- }
-
- const char *getName(unsigned Opcode) const {
- return get(Opcode).Name;
- }
-
- int getNumOperands(unsigned Opcode) const {
- return get(Opcode).numOperands;
- }
-
- int getNumDefs(unsigned Opcode) const {
- return get(Opcode).numDefs;
- }
-
- const unsigned *getImplicitUses(unsigned Opcode) const {
- return get(Opcode).ImplicitUses;
- }
-
- const unsigned *getImplicitDefs(unsigned Opcode) const {
- return get(Opcode).ImplicitDefs;
- }
-
-
- //
- // Query instruction class flags according to the machine-independent
- // flags listed above.
- //
- bool isReturn(unsigned Opcode) const {
- return get(Opcode).Flags & M_RET_FLAG;
+ TargetInstrInfo(int CFSetupOpcode = -1, int CFDestroyOpcode = -1)
+ : CallFrameSetupOpcode(CFSetupOpcode),
+ CallFrameDestroyOpcode(CFDestroyOpcode) {
}
- bool isCommutableInstr(unsigned Opcode) const {
- return get(Opcode).Flags & M_COMMUTABLE;
- }
-
- /// usesCustomDAGSchedInsertionHook - Return true if this instruction requires
- /// custom insertion support when the DAG scheduler is inserting it into a
- /// machine basic block.
- bool usesCustomDAGSchedInsertionHook(unsigned Opcode) const {
- return get(Opcode).Flags & M_USES_CUSTOM_DAG_SCHED_INSERTION;
- }
-
- bool hasVariableOperands(unsigned Opcode) const {
- return get(Opcode).Flags & M_VARIABLE_OPS;
- }
+ virtual ~TargetInstrInfo();
- bool hasOptionalDef(unsigned Opcode) const {
- return get(Opcode).Flags & M_HAS_OPTIONAL_DEF;
- }
+ /// getRegClass - Givem a machine instruction descriptor, returns the register
+ /// class constraint for OpNum, or NULL.
+ const TargetRegisterClass *getRegClass(const MCInstrDesc &TID,
+ unsigned OpNum,
+ const TargetRegisterInfo *TRI,
+ const MachineFunction &MF) const;
/// isTriviallyReMaterializable - Return true if the instruction is trivially
/// rematerializable, meaning it has no side effects and requires no operands
/// that aren't always available.
- bool isTriviallyReMaterializable(MachineInstr *MI) const {
- return (MI->getDesc()->Flags & M_REMATERIALIZIBLE) &&
- isReallyTriviallyReMaterializable(MI);
+ bool isTriviallyReMaterializable(const MachineInstr *MI,
+ AliasAnalysis *AA = 0) const {
+ return MI->getOpcode() == TargetOpcode::IMPLICIT_DEF ||
+ (MI->getDesc().isRematerializable() &&
+ (isReallyTriviallyReMaterializable(MI, AA) ||
+ isReallyTriviallyReMaterializableGeneric(MI, AA)));
}
- /// hasUnmodelledSideEffects - Returns true if the instruction has side
- /// effects that are not captured by any operands of the instruction or other
- /// flags.
- bool hasUnmodelledSideEffects(MachineInstr *MI) const {
- const TargetInstrDescriptor *TID = MI->getDesc();
- if (TID->Flags & M_NEVER_HAS_SIDE_EFFECTS) return false;
- if (!(TID->Flags & M_MAY_HAVE_SIDE_EFFECTS)) return true;
- return !isReallySideEffectFree(MI); // May have side effects
- }
protected:
/// isReallyTriviallyReMaterializable - For instructions with opcodes for
- /// which the M_REMATERIALIZABLE flag is set, this function tests whether the
- /// instruction itself is actually trivially rematerializable, considering
- /// its operands. This is used for targets that have instructions that are
- /// only trivially rematerializable for specific uses. This predicate must
- /// return false if the instruction has any side effects other than
- /// producing a value, or if it requres any address registers that are not
- /// always available.
- virtual bool isReallyTriviallyReMaterializable(MachineInstr *MI) const {
- return true;
- }
-
- /// isReallySideEffectFree - If the M_MAY_HAVE_SIDE_EFFECTS flag is set, this
- /// method is called to determine if the specific instance of this
- /// instruction has side effects. This is useful in cases of instructions,
- /// like loads, which generally always have side effects. A load from a
- /// constant pool doesn't have side effects, though. So we need to
- /// differentiate it from the general case.
- virtual bool isReallySideEffectFree(MachineInstr *MI) const {
+ /// which the M_REMATERIALIZABLE flag is set, this hook lets the target
+ /// specify whether the instruction is actually trivially rematerializable,
+ /// taking into consideration its operands. This predicate must return false
+ /// if the instruction has any side effects other than producing a value, or
+ /// if it requres any address registers that are not always available.
+ virtual bool isReallyTriviallyReMaterializable(const MachineInstr *MI,
+ AliasAnalysis *AA) const {
return false;
}
+
+private:
+ /// isReallyTriviallyReMaterializableGeneric - For instructions with opcodes
+ /// for which the M_REMATERIALIZABLE flag is set and the target hook
+ /// isReallyTriviallyReMaterializable returns false, this function does
+ /// target-independent tests to determine if the instruction is really
+ /// trivially rematerializable.
+ bool isReallyTriviallyReMaterializableGeneric(const MachineInstr *MI,
+ AliasAnalysis *AA) const;
+
public:
- /// getOperandConstraint - Returns the value of the specific constraint if
- /// it is set. Returns -1 if it is not set.
- int getOperandConstraint(unsigned Opcode, unsigned OpNum,
- TOI::OperandConstraint Constraint) const {
- return get(Opcode).getOperandConstraint(OpNum, Constraint);
- }
-
- /// Return true if the instruction is a register to register move
- /// and leave the source and dest operands in the passed parameters.
- virtual bool isMoveInstr(const MachineInstr& MI,
- unsigned& sourceReg,
- unsigned& destReg) const {
+ /// 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
+ /// between operating with a frame pointer and operating without, through the
+ /// use of these two instructions.
+ ///
+ int getCallFrameSetupOpcode() const { return CallFrameSetupOpcode; }
+ int getCallFrameDestroyOpcode() const { return CallFrameDestroyOpcode; }
+
+ /// isCoalescableExtInstr - Return true if the instruction is a "coalescable"
+ /// extension instruction. That is, it's like a copy where it's legal for the
+ /// source to overlap the destination. e.g. X86::MOVSX64rr32. If this returns
+ /// true, then it's expected the pre-extension value is available as a subreg
+ /// of the result register. This also returns the sub-register index in
+ /// SubIdx.
+ virtual bool isCoalescableExtInstr(const MachineInstr &MI,
+ unsigned &SrcReg, unsigned &DstReg,
+ unsigned &SubIdx) const {
return false;
}
-
+
/// isLoadFromStackSlot - If the specified machine instruction is a direct
/// load from a stack slot, return the virtual or physical register number of
/// the destination along with the FrameIndex of the loaded stack slot. If
/// not, return 0. This predicate must return 0 if the instruction has
/// any side effects other than loading from the stack slot.
- virtual unsigned isLoadFromStackSlot(MachineInstr *MI, int &FrameIndex) const{
+ virtual unsigned isLoadFromStackSlot(const MachineInstr *MI,
+ int &FrameIndex) const {
+ return 0;
+ }
+
+ /// isLoadFromStackSlotPostFE - Check for post-frame ptr elimination
+ /// stack locations as well. This uses a heuristic so it isn't
+ /// reliable for correctness.
+ virtual unsigned isLoadFromStackSlotPostFE(const MachineInstr *MI,
+ int &FrameIndex) const {
+ return 0;
+ }
+
+ /// hasLoadFromStackSlot - If the specified machine instruction has
+ /// a load from a stack slot, return true along with the FrameIndex
+ /// of the loaded stack slot and the machine mem operand containing
+ /// the reference. If not, return false. Unlike
+ /// isLoadFromStackSlot, this returns true for any instructions that
+ /// loads from the stack. This is just a hint, as some cases may be
+ /// missed.
+ virtual bool hasLoadFromStackSlot(const MachineInstr *MI,
+ const MachineMemOperand *&MMO,
+ int &FrameIndex) const {
return 0;
}
-
+
/// isStoreToStackSlot - If the specified machine instruction is a direct
/// store to a stack slot, return the virtual or physical register number of
/// the source reg along with the FrameIndex of the loaded stack slot. If
/// not, return 0. This predicate must return 0 if the instruction has
/// any side effects other than storing to the stack slot.
- virtual unsigned isStoreToStackSlot(MachineInstr *MI, int &FrameIndex) const {
+ virtual unsigned isStoreToStackSlot(const MachineInstr *MI,
+ int &FrameIndex) const {
+ return 0;
+ }
+
+ /// isStoreToStackSlotPostFE - Check for post-frame ptr elimination
+ /// stack locations as well. This uses a heuristic so it isn't
+ /// reliable for correctness.
+ virtual unsigned isStoreToStackSlotPostFE(const MachineInstr *MI,
+ int &FrameIndex) const {
+ return 0;
+ }
+
+ /// hasStoreToStackSlot - If the specified machine instruction has a
+ /// store to a stack slot, return true along with the FrameIndex of
+ /// the loaded stack slot and the machine mem operand containing the
+ /// reference. If not, return false. Unlike isStoreToStackSlot,
+ /// this returns true for any instructions that stores to the
+ /// stack. This is just a hint, as some cases may be missed.
+ virtual bool hasStoreToStackSlot(const MachineInstr *MI,
+ const MachineMemOperand *&MMO,
+ int &FrameIndex) const {
return 0;
}
+ /// reMaterialize - Re-issue the specified 'original' instruction at the
+ /// specific location targeting a new destination register.
+ /// The register in Orig->getOperand(0).getReg() will be substituted by
+ /// DestReg:SubIdx. Any existing subreg index is preserved or composed with
+ /// SubIdx.
+ virtual void reMaterialize(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ unsigned DestReg, unsigned SubIdx,
+ const MachineInstr *Orig,
+ const TargetRegisterInfo &TRI) const = 0;
+
+ /// duplicate - Create a duplicate of the Orig instruction in MF. This is like
+ /// MachineFunction::CloneMachineInstr(), but the target may update operands
+ /// that are required to be unique.
+ ///
+ /// The instruction must be duplicable as indicated by isNotDuplicable().
+ virtual MachineInstr *duplicate(MachineInstr *Orig,
+ MachineFunction &MF) const = 0;
+
/// convertToThreeAddress - This method must be implemented by targets that
/// set the M_CONVERTIBLE_TO_3_ADDR flag. When this flag is set, the target
/// may be able to convert a two-address instruction into one or more true
///
virtual MachineInstr *
convertToThreeAddress(MachineFunction::iterator &MFI,
- MachineBasicBlock::iterator &MBBI, LiveVariables &LV) const {
+ MachineBasicBlock::iterator &MBBI, LiveVariables *LV) const {
return 0;
}
- /// commuteInstruction - If a target has any instructions that are commutable,
- /// but require converting to a different instruction or making non-trivial
- /// changes to commute them, this method can overloaded to do this. The
- /// default implementation of this method simply swaps the first two operands
- /// of MI and returns it.
- ///
- /// If a target wants to make more aggressive changes, they can construct and
- /// return a new machine instruction. If an instruction cannot commute, it
- /// can also return null.
- ///
- virtual MachineInstr *commuteInstruction(MachineInstr *MI) const = 0;
+ /// commuteInstruction - If a target has any instructions that are
+ /// commutable but require converting to different instructions or making
+ /// non-trivial changes to commute them, this method can overloaded to do
+ /// that. The default implementation simply swaps the commutable operands.
+ /// If NewMI is false, MI is modified in place and returned; otherwise, a
+ /// new machine instruction is created and returned. Do not call this
+ /// method for a non-commutable instruction, but there may be some cases
+ /// where this method fails and returns null.
+ virtual MachineInstr *commuteInstruction(MachineInstr *MI,
+ bool NewMI = false) const = 0;
+
+ /// findCommutedOpIndices - If specified MI is commutable, return the two
+ /// operand indices that would swap value. Return false if the instruction
+ /// is not in a form which this routine understands.
+ virtual bool findCommutedOpIndices(MachineInstr *MI, unsigned &SrcOpIdx1,
+ unsigned &SrcOpIdx2) const = 0;
+
+ /// produceSameValue - Return true if two machine instructions would produce
+ /// identical values. By default, this is only true when the two instructions
+ /// are deemed identical except for defs. If this function is called when the
+ /// IR is still in SSA form, the caller can pass the MachineRegisterInfo for
+ /// aggressive checks.
+ virtual bool produceSameValue(const MachineInstr *MI0,
+ const MachineInstr *MI1,
+ const MachineRegisterInfo *MRI = 0) const = 0;
/// AnalyzeBranch - Analyze the branching code at the end of MBB, returning
/// true if it cannot be understood (e.g. it's a switch dispatch or isn't
/// just return false, leaving TBB/FBB null.
/// 2. If this block ends with only an unconditional branch, it sets TBB to be
/// the destination block.
- /// 3. If this block ends with an conditional branch and it falls through to
- /// an successor block, it sets TBB to be the branch destination block and a
- /// list of operands that evaluate the condition. These
- /// operands can be passed to other TargetInstrInfo methods to create new
- /// branches.
- /// 4. If this block ends with an conditional branch and an unconditional
- /// block, it returns the 'true' destination in TBB, the 'false' destination
- /// in FBB, and a list of operands that evaluate the condition. These
- /// operands can be passed to other TargetInstrInfo methods to create new
- /// branches.
+ /// 3. If this block ends with a conditional branch and it falls through to a
+ /// successor block, it sets TBB to be the branch destination block and a
+ /// list of operands that evaluate the condition. These operands can be
+ /// passed to other TargetInstrInfo methods to create new branches.
+ /// 4. If this block ends with a conditional branch followed by an
+ /// unconditional branch, it returns the 'true' destination in TBB, the
+ /// 'false' destination in FBB, and a list of operands that evaluate the
+ /// condition. These operands can be passed to other TargetInstrInfo
+ /// methods to create new branches.
///
/// Note that RemoveBranch and InsertBranch must be implemented to support
/// cases where this method returns success.
///
+ /// If AllowModify is true, then this routine is allowed to modify the basic
+ /// block (e.g. delete instructions after the unconditional branch).
+ ///
virtual bool AnalyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
- std::vector<MachineOperand> &Cond) const {
+ SmallVectorImpl<MachineOperand> &Cond,
+ bool AllowModify = false) const {
return true;
}
-
+
/// RemoveBranch - Remove the branching code at the end of the specific MBB.
- /// this is only invoked in cases where AnalyzeBranch returns success. It
+ /// This is only invoked in cases where AnalyzeBranch returns success. It
/// returns the number of instructions that were removed.
virtual unsigned RemoveBranch(MachineBasicBlock &MBB) const {
- assert(0 && "Target didn't implement TargetInstrInfo::RemoveBranch!");
- return 0;
+ llvm_unreachable("Target didn't implement TargetInstrInfo::RemoveBranch!");
}
-
- /// InsertBranch - Insert a branch into the end of the specified
- /// MachineBasicBlock. This operands to this method are the same as those
- /// returned by AnalyzeBranch. This is invoked in cases where AnalyzeBranch
- /// returns success and when an unconditional branch (TBB is non-null, FBB is
- /// null, Cond is empty) needs to be inserted. It returns the number of
- /// instructions inserted.
+
+ /// InsertBranch - Insert branch code into the end of the specified
+ /// MachineBasicBlock. The operands to this method are the same as those
+ /// returned by AnalyzeBranch. This is only invoked in cases where
+ /// AnalyzeBranch returns success. It returns the number of instructions
+ /// inserted.
+ ///
+ /// It is also invoked by tail merging to add unconditional branches in
+ /// cases where AnalyzeBranch doesn't apply because there was no original
+ /// branch to analyze. At least this much must be implemented, else tail
+ /// merging needs to be disabled.
virtual unsigned InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
- MachineBasicBlock *FBB,
- const std::vector<MachineOperand> &Cond) const {
- assert(0 && "Target didn't implement TargetInstrInfo::InsertBranch!");
- return 0;
+ MachineBasicBlock *FBB,
+ const SmallVectorImpl<MachineOperand> &Cond,
+ DebugLoc DL) const {
+ llvm_unreachable("Target didn't implement TargetInstrInfo::InsertBranch!");
+ }
+
+ /// ReplaceTailWithBranchTo - Delete the instruction OldInst and everything
+ /// after it, replacing it with an unconditional branch to NewDest. This is
+ /// used by the tail merging pass.
+ virtual void ReplaceTailWithBranchTo(MachineBasicBlock::iterator Tail,
+ MachineBasicBlock *NewDest) const = 0;
+
+ /// isLegalToSplitMBBAt - Return true if it's legal to split the given basic
+ /// block at the specified instruction (i.e. instruction would be the start
+ /// of a new basic block).
+ virtual bool isLegalToSplitMBBAt(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MBBI) const {
+ return true;
+ }
+
+ /// isProfitableToIfCvt - Return true if it's profitable to predicate
+ /// instructions with accumulated instruction latency of "NumCycles"
+ /// of the specified basic block, where the probability of the instructions
+ /// being executed is given by Probability, and Confidence is a measure
+ /// of our confidence that it will be properly predicted.
+ virtual
+ bool isProfitableToIfCvt(MachineBasicBlock &MBB, unsigned NumCycles,
+ unsigned ExtraPredCycles,
+ const BranchProbability &Probability) const {
+ return false;
+ }
+
+ /// isProfitableToIfCvt - Second variant of isProfitableToIfCvt, this one
+ /// checks for the case where two basic blocks from true and false path
+ /// of a if-then-else (diamond) are predicated on mutally exclusive
+ /// predicates, where the probability of the true path being taken is given
+ /// by Probability, and Confidence is a measure of our confidence that it
+ /// will be properly predicted.
+ virtual bool
+ isProfitableToIfCvt(MachineBasicBlock &TMBB,
+ unsigned NumTCycles, unsigned ExtraTCycles,
+ MachineBasicBlock &FMBB,
+ unsigned NumFCycles, unsigned ExtraFCycles,
+ const BranchProbability &Probability) const {
+ return false;
+ }
+
+ /// isProfitableToDupForIfCvt - Return true if it's profitable for
+ /// if-converter to duplicate instructions of specified accumulated
+ /// instruction latencies in the specified MBB to enable if-conversion.
+ /// The probability of the instructions being executed is given by
+ /// Probability, and Confidence is a measure of our confidence that it
+ /// will be properly predicted.
+ virtual bool
+ isProfitableToDupForIfCvt(MachineBasicBlock &MBB, unsigned NumCycles,
+ const BranchProbability &Probability) const {
+ return false;
+ }
+
+ /// isProfitableToUnpredicate - Return true if it's profitable to unpredicate
+ /// one side of a 'diamond', i.e. two sides of if-else predicated on mutually
+ /// exclusive predicates.
+ /// e.g.
+ /// subeq r0, r1, #1
+ /// addne r0, r1, #1
+ /// =>
+ /// sub r0, r1, #1
+ /// addne r0, r1, #1
+ ///
+ /// This may be profitable is conditional instructions are always executed.
+ virtual bool isProfitableToUnpredicate(MachineBasicBlock &TMBB,
+ MachineBasicBlock &FMBB) const {
+ return false;
+ }
+
+ /// canInsertSelect - Return true if it is possible to insert a select
+ /// instruction that chooses between TrueReg and FalseReg based on the
+ /// condition code in Cond.
+ ///
+ /// When successful, also return the latency in cycles from TrueReg,
+ /// FalseReg, and Cond to the destination register. The Cond latency should
+ /// compensate for a conditional branch being removed. For example, if a
+ /// conditional branch has a 3 cycle latency from the condition code read,
+ /// and a cmov instruction has a 2 cycle latency from the condition code
+ /// read, CondCycles should be returned as -1.
+ ///
+ /// @param MBB Block where select instruction would be inserted.
+ /// @param Cond Condition returned by AnalyzeBranch.
+ /// @param TrueReg Virtual register to select when Cond is true.
+ /// @param FalseReg Virtual register to select when Cond is false.
+ /// @param CondCycles Latency from Cond+Branch to select output.
+ /// @param TrueCycles Latency from TrueReg to select output.
+ /// @param FalseCycles Latency from FalseReg to select output.
+ virtual bool canInsertSelect(const MachineBasicBlock &MBB,
+ const SmallVectorImpl<MachineOperand> &Cond,
+ unsigned TrueReg, unsigned FalseReg,
+ int &CondCycles,
+ int &TrueCycles, int &FalseCycles) const {
+ return false;
+ }
+
+ /// insertSelect - Insert a select instruction into MBB before I that will
+ /// copy TrueReg to DstReg when Cond is true, and FalseReg to DstReg when
+ /// Cond is false.
+ ///
+ /// This function can only be called after canInsertSelect() returned true.
+ /// The condition in Cond comes from AnalyzeBranch, and it can be assumed
+ /// that the same flags or registers required by Cond are available at the
+ /// insertion point.
+ ///
+ /// @param MBB Block where select instruction should be inserted.
+ /// @param I Insertion point.
+ /// @param DL Source location for debugging.
+ /// @param DstReg Virtual register to be defined by select instruction.
+ /// @param Cond Condition as computed by AnalyzeBranch.
+ /// @param TrueReg Virtual register to copy when Cond is true.
+ /// @param FalseReg Virtual register to copy when Cons is false.
+ virtual void insertSelect(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator I, DebugLoc DL,
+ unsigned DstReg,
+ const SmallVectorImpl<MachineOperand> &Cond,
+ unsigned TrueReg, unsigned FalseReg) const {
+ llvm_unreachable("Target didn't implement TargetInstrInfo::insertSelect!");
+ }
+
+ /// analyzeSelect - Analyze the given select instruction, returning true if
+ /// it cannot be understood. It is assumed that MI->isSelect() is true.
+ ///
+ /// When successful, return the controlling condition and the operands that
+ /// determine the true and false result values.
+ ///
+ /// Result = SELECT Cond, TrueOp, FalseOp
+ ///
+ /// Some targets can optimize select instructions, for example by predicating
+ /// the instruction defining one of the operands. Such targets should set
+ /// Optimizable.
+ ///
+ /// @param MI Select instruction to analyze.
+ /// @param Cond Condition controlling the select.
+ /// @param TrueOp Operand number of the value selected when Cond is true.
+ /// @param FalseOp Operand number of the value selected when Cond is false.
+ /// @param Optimizable Returned as true if MI is optimizable.
+ /// @returns False on success.
+ virtual bool analyzeSelect(const MachineInstr *MI,
+ SmallVectorImpl<MachineOperand> &Cond,
+ unsigned &TrueOp, unsigned &FalseOp,
+ bool &Optimizable) const {
+ assert(MI && MI->isSelect() && "MI must be a select instruction");
+ return true;
+ }
+
+ /// optimizeSelect - Given a select instruction that was understood by
+ /// analyzeSelect and returned Optimizable = true, attempt to optimize MI by
+ /// merging it with one of its operands. Returns NULL on failure.
+ ///
+ /// When successful, returns the new select instruction. The client is
+ /// responsible for deleting MI.
+ ///
+ /// If both sides of the select can be optimized, PreferFalse is used to pick
+ /// a side.
+ ///
+ /// @param MI Optimizable select instruction.
+ /// @param PreferFalse Try to optimize FalseOp instead of TrueOp.
+ /// @returns Optimized instruction or NULL.
+ virtual MachineInstr *optimizeSelect(MachineInstr *MI,
+ bool PreferFalse = false) const {
+ // This function must be implemented if Optimizable is ever set.
+ llvm_unreachable("Target must implement TargetInstrInfo::optimizeSelect!");
}
-
- /// copyRegToReg - Add a copy between a pair of registers
- virtual void copyRegToReg(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator MI,
- unsigned DestReg, unsigned SrcReg,
- const TargetRegisterClass *DestRC,
- const TargetRegisterClass *SrcRC) const {
- assert(0 && "Target didn't implement TargetInstrInfo::copyRegToReg!");
+
+ /// copyPhysReg - Emit instructions to copy a pair of physical registers.
+ ///
+ /// This function should support copies within any legal register class as
+ /// well as any cross-class copies created during instruction selection.
+ ///
+ /// The source and destination registers may overlap, which may require a
+ /// careful implementation when multiple copy instructions are required for
+ /// large registers. See for example the ARM target.
+ virtual void copyPhysReg(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI, DebugLoc DL,
+ unsigned DestReg, unsigned SrcReg,
+ bool KillSrc) const {
+ llvm_unreachable("Target didn't implement TargetInstrInfo::copyPhysReg!");
}
-
+
+ /// storeRegToStackSlot - Store the specified register of the given register
+ /// class to the specified stack frame index. The store instruction is to be
+ /// added to the given machine basic block before the specified machine
+ /// instruction. If isKill is true, the register operand is the last use and
+ /// must be marked kill.
virtual void storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned SrcReg, bool isKill, int FrameIndex,
- const TargetRegisterClass *RC) const {
- assert(0 && "Target didn't implement TargetInstrInfo::storeRegToStackSlot!");
- }
-
- virtual void storeRegToAddr(MachineFunction &MF, unsigned SrcReg, bool isKill,
- SmallVectorImpl<MachineOperand> &Addr,
- const TargetRegisterClass *RC,
- SmallVectorImpl<MachineInstr*> &NewMIs) const {
- assert(0 && "Target didn't implement TargetInstrInfo::storeRegToAddr!");
+ const TargetRegisterClass *RC,
+ const TargetRegisterInfo *TRI) const {
+ llvm_unreachable("Target didn't implement "
+ "TargetInstrInfo::storeRegToStackSlot!");
}
+ /// loadRegFromStackSlot - Load the specified register of the given register
+ /// class from the specified stack frame index. The load instruction is to be
+ /// added to the given machine basic block before the specified machine
+ /// instruction.
virtual void loadRegFromStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, int FrameIndex,
- const TargetRegisterClass *RC) const {
- assert(0 && "Target didn't implement TargetInstrInfo::loadRegFromStackSlot!");
- }
-
- virtual void loadRegFromAddr(MachineFunction &MF, unsigned DestReg,
- SmallVectorImpl<MachineOperand> &Addr,
- const TargetRegisterClass *RC,
- SmallVectorImpl<MachineInstr*> &NewMIs) const {
- assert(0 && "Target didn't implement TargetInstrInfo::loadRegFromAddr!");
- }
-
- /// 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;
+ const TargetRegisterClass *RC,
+ const TargetRegisterInfo *TRI) const {
+ llvm_unreachable("Target didn't implement "
+ "TargetInstrInfo::loadRegFromStackSlot!");
}
- /// 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 {
+ /// expandPostRAPseudo - This function is called for all pseudo instructions
+ /// that remain after register allocation. Many pseudo instructions are
+ /// created to help register allocation. This is the place to convert them
+ /// into real instructions. The target can edit MI in place, or it can insert
+ /// new instructions and erase MI. The function should return true if
+ /// anything was changed.
+ virtual bool expandPostRAPseudo(MachineBasicBlock::iterator MI) const {
return false;
}
-
+
+ /// emitFrameIndexDebugValue - Emit a target-dependent form of
+ /// DBG_VALUE encoding the address of a frame index. Addresses would
+ /// normally be lowered the same way as other addresses on the target,
+ /// e.g. in load instructions. For targets that do not support this
+ /// the debug info is simply lost.
+ /// If you add this for a target you should handle this DBG_VALUE in the
+ /// target-specific AsmPrinter code as well; you will probably get invalid
+ /// assembly output if you don't.
+ virtual MachineInstr *emitFrameIndexDebugValue(MachineFunction &MF,
+ int FrameIx,
+ uint64_t Offset,
+ const MDNode *MDPtr,
+ DebugLoc dl) const {
+ return 0;
+ }
+
/// foldMemoryOperand - Attempt to fold a load or store of the specified stack
/// slot into the specified machine instruction for the specified operand(s).
/// If this is possible, a new instruction is returned with the specified
- /// operand folded, otherwise NULL is returned. The client is responsible for
- /// removing the old instruction and adding the new one in the instruction
- /// stream.
- virtual MachineInstr* foldMemoryOperand(MachineInstr* MI,
- SmallVectorImpl<unsigned> &Ops,
- int FrameIndex) const {
- return 0;
- }
+ /// operand folded, otherwise NULL is returned.
+ /// The new instruction is inserted before MI, and the client is responsible
+ /// for removing the old instruction.
+ MachineInstr* foldMemoryOperand(MachineBasicBlock::iterator MI,
+ const SmallVectorImpl<unsigned> &Ops,
+ int FrameIndex) const;
/// foldMemoryOperand - Same as the previous version except it allows folding
/// of any load and store from / to any address, not just from a specific
/// stack slot.
- virtual MachineInstr* foldMemoryOperand(MachineInstr* MI,
- SmallVectorImpl<unsigned> &Ops,
- MachineInstr* LoadMI) const {
+ MachineInstr* foldMemoryOperand(MachineBasicBlock::iterator MI,
+ const SmallVectorImpl<unsigned> &Ops,
+ MachineInstr* LoadMI) const;
+
+protected:
+ /// foldMemoryOperandImpl - Target-dependent implementation for
+ /// foldMemoryOperand. Target-independent code in foldMemoryOperand will
+ /// take care of adding a MachineMemOperand to the newly created instruction.
+ virtual MachineInstr* foldMemoryOperandImpl(MachineFunction &MF,
+ MachineInstr* MI,
+ const SmallVectorImpl<unsigned> &Ops,
+ int FrameIndex) const {
return 0;
}
- /// canFoldMemoryOperand - Returns true if the specified load / store is
+ /// foldMemoryOperandImpl - Target-dependent implementation for
+ /// foldMemoryOperand. Target-independent code in foldMemoryOperand will
+ /// take care of adding a MachineMemOperand to the newly created instruction.
+ virtual MachineInstr* foldMemoryOperandImpl(MachineFunction &MF,
+ MachineInstr* MI,
+ const SmallVectorImpl<unsigned> &Ops,
+ MachineInstr* LoadMI) const {
+ return 0;
+ }
+
+public:
+ /// canFoldMemoryOperand - Returns true for the specified load / store if
/// folding is possible.
virtual
- bool canFoldMemoryOperand(MachineInstr *MI,
- SmallVectorImpl<unsigned> &Ops) const{
- return false;
- }
+ bool canFoldMemoryOperand(const MachineInstr *MI,
+ const SmallVectorImpl<unsigned> &Ops) const =0;
/// unfoldMemoryOperand - Separate a single instruction which folded a load or
/// a store or a load and a store into two or more instruction. If this is
/// possible, returns true as well as the new instructions by reference.
virtual bool unfoldMemoryOperand(MachineFunction &MF, MachineInstr *MI,
unsigned Reg, bool UnfoldLoad, bool UnfoldStore,
- SmallVectorImpl<MachineInstr*> &NewMIs) const{
+ SmallVectorImpl<MachineInstr*> &NewMIs) const{
return false;
}
/// getOpcodeAfterMemoryUnfold - Returns the opcode of the would be new
/// instruction after load / store are unfolded from an instruction of the
/// specified opcode. It returns zero if the specified unfolding is not
- /// possible.
+ /// possible. If LoadRegIndex is non-null, it is filled in with the operand
+ /// index of the operand which will hold the register holding the loaded
+ /// value.
virtual unsigned getOpcodeAfterMemoryUnfold(unsigned Opc,
- bool UnfoldLoad, bool UnfoldStore) const {
+ bool UnfoldLoad, bool UnfoldStore,
+ unsigned *LoadRegIndex = 0) const {
return 0;
}
-
- /// BlockHasNoFallThrough - Return true if the specified block does not
- /// fall-through into its successor block. This is primarily used when a
- /// branch is unanalyzable. It is useful for things like unconditional
- /// indirect branches (jump tables).
- virtual bool BlockHasNoFallThrough(MachineBasicBlock &MBB) const {
+
+ /// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler
+ /// to determine if two loads are loading from the same base address. It
+ /// should only return true if the base pointers are the same and the
+ /// only differences between the two addresses are the offset. It also returns
+ /// the offsets by reference.
+ virtual bool areLoadsFromSameBasePtr(SDNode *Load1, SDNode *Load2,
+ int64_t &Offset1, int64_t &Offset2) const {
return false;
}
-
+
+ /// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to
+ /// determine (in conjunction with areLoadsFromSameBasePtr) if two loads should
+ /// be scheduled togther. On some targets if two loads are loading from
+ /// addresses in the same cache line, it's better if they are scheduled
+ /// together. This function takes two integers that represent the load offsets
+ /// from the common base address. It returns true if it decides it's desirable
+ /// to schedule the two loads together. "NumLoads" is the number of loads that
+ /// have already been scheduled after Load1.
+ virtual bool shouldScheduleLoadsNear(SDNode *Load1, SDNode *Load2,
+ int64_t Offset1, int64_t Offset2,
+ unsigned NumLoads) const {
+ return false;
+ }
+
/// ReverseBranchCondition - Reverses the branch condition of the specified
/// condition list, returning false on success and true if it cannot be
/// reversed.
- virtual bool ReverseBranchCondition(std::vector<MachineOperand> &Cond) const {
+ virtual
+ bool ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const {
return true;
}
-
+
/// insertNoop - Insert a noop into the instruction stream at the specified
/// point.
- virtual void insertNoop(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator MI) const {
- assert(0 && "Target didn't implement insertNoop!");
- abort();
+ virtual void insertNoop(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI) const;
+
+
+ /// getNoopForMachoTarget - Return the noop instruction to use for a noop.
+ virtual void getNoopForMachoTarget(MCInst &NopInst) const {
+ // Default to just using 'nop' string.
}
+
/// isPredicated - Returns true if the instruction is already predicated.
///
virtual bool isPredicated(const MachineInstr *MI) const {
/// isUnpredicatedTerminator - Returns true if the instruction is a
/// terminator instruction that has not been predicated.
- virtual bool isUnpredicatedTerminator(const MachineInstr *MI) const;
+ virtual bool isUnpredicatedTerminator(const MachineInstr *MI) const = 0;
/// PredicateInstruction - Convert the instruction into a predicated
/// instruction. It returns true if the operation was successful.
virtual
bool PredicateInstruction(MachineInstr *MI,
- const std::vector<MachineOperand> &Pred) const = 0;
+ const SmallVectorImpl<MachineOperand> &Pred) const = 0;
/// SubsumesPredicate - Returns true if the first specified predicate
/// subsumes the second, e.g. GE subsumes GT.
virtual
- bool SubsumesPredicate(const std::vector<MachineOperand> &Pred1,
- const std::vector<MachineOperand> &Pred2) const {
+ bool SubsumesPredicate(const SmallVectorImpl<MachineOperand> &Pred1,
+ const SmallVectorImpl<MachineOperand> &Pred2) const {
return false;
}
return false;
}
- /// getPointerRegClass - Returns a TargetRegisterClass used for pointer
- /// values.
- virtual const TargetRegisterClass *getPointerRegClass() const {
- assert(0 && "Target didn't implement getPointerRegClass!");
- abort();
- return 0; // Must return a value in order to compile with VS 2005
+ /// isPredicable - Return true if the specified instruction can be predicated.
+ /// By default, this returns true for every instruction with a
+ /// PredicateOperand.
+ virtual bool isPredicable(MachineInstr *MI) const {
+ return MI->getDesc().isPredicable();
+ }
+
+ /// isSafeToMoveRegClassDefs - Return true if it's safe to move a machine
+ /// instruction that defines the specified register class.
+ virtual bool isSafeToMoveRegClassDefs(const TargetRegisterClass *RC) const {
+ return true;
+ }
+
+ /// isSchedulingBoundary - Test if the given instruction should be
+ /// considered a scheduling boundary. This primarily includes labels and
+ /// terminators.
+ virtual bool isSchedulingBoundary(const MachineInstr *MI,
+ const MachineBasicBlock *MBB,
+ const MachineFunction &MF) const = 0;
+
+ /// Measure the specified inline asm to determine an approximation of its
+ /// length.
+ virtual unsigned getInlineAsmLength(const char *Str,
+ const MCAsmInfo &MAI) const;
+
+ /// CreateTargetHazardRecognizer - Allocate and return a hazard recognizer to
+ /// use for this target when scheduling the machine instructions before
+ /// register allocation.
+ virtual ScheduleHazardRecognizer*
+ CreateTargetHazardRecognizer(const TargetMachine *TM,
+ const ScheduleDAG *DAG) const = 0;
+
+ /// CreateTargetMIHazardRecognizer - Allocate and return a hazard recognizer
+ /// to use for this target when scheduling the machine instructions before
+ /// register allocation.
+ virtual ScheduleHazardRecognizer*
+ CreateTargetMIHazardRecognizer(const InstrItineraryData*,
+ const ScheduleDAG *DAG) const = 0;
+
+ /// CreateTargetPostRAHazardRecognizer - Allocate and return a hazard
+ /// recognizer to use for this target when scheduling the machine instructions
+ /// after register allocation.
+ virtual ScheduleHazardRecognizer*
+ CreateTargetPostRAHazardRecognizer(const InstrItineraryData*,
+ const ScheduleDAG *DAG) const = 0;
+
+ /// analyzeCompare - For a comparison instruction, return the source registers
+ /// in SrcReg and SrcReg2 if having two register operands, and the value it
+ /// compares against in CmpValue. Return true if the comparison instruction
+ /// can be analyzed.
+ virtual bool analyzeCompare(const MachineInstr *MI,
+ unsigned &SrcReg, unsigned &SrcReg2,
+ int &Mask, int &Value) const {
+ return false;
+ }
+
+ /// optimizeCompareInstr - See if the comparison instruction can be converted
+ /// into something more efficient. E.g., on ARM most instructions can set the
+ /// flags register, obviating the need for a separate CMP.
+ virtual bool optimizeCompareInstr(MachineInstr *CmpInstr,
+ unsigned SrcReg, unsigned SrcReg2,
+ int Mask, int Value,
+ const MachineRegisterInfo *MRI) const {
+ return false;
+ }
+
+ /// optimizeLoadInstr - Try to remove the load by folding it to a register
+ /// operand at the use. We fold the load instructions if and only if the
+ /// def and use are in the same BB. We only look at one load and see
+ /// whether it can be folded into MI. FoldAsLoadDefReg is the virtual register
+ /// defined by the load we are trying to fold. DefMI returns the machine
+ /// instruction that defines FoldAsLoadDefReg, and the function returns
+ /// the machine instruction generated due to folding.
+ virtual MachineInstr* optimizeLoadInstr(MachineInstr *MI,
+ const MachineRegisterInfo *MRI,
+ unsigned &FoldAsLoadDefReg,
+ MachineInstr *&DefMI) const {
+ return 0;
+ }
+
+ /// FoldImmediate - 'Reg' is known to be defined by a move immediate
+ /// instruction, try to fold the immediate into the use instruction.
+ virtual bool FoldImmediate(MachineInstr *UseMI, MachineInstr *DefMI,
+ unsigned Reg, MachineRegisterInfo *MRI) const {
+ return false;
+ }
+
+ /// getNumMicroOps - Return the number of u-operations the given machine
+ /// instruction will be decoded to on the target cpu. The itinerary's
+ /// IssueWidth is the number of microops that can be dispatched each
+ /// cycle. An instruction with zero microops takes no dispatch resources.
+ virtual unsigned getNumMicroOps(const InstrItineraryData *ItinData,
+ const MachineInstr *MI) const = 0;
+
+ /// isZeroCost - Return true for pseudo instructions that don't consume any
+ /// machine resources in their current form. These are common cases that the
+ /// scheduler should consider free, rather than conservatively handling them
+ /// as instructions with no itinerary.
+ bool isZeroCost(unsigned Opcode) const {
+ return Opcode <= TargetOpcode::COPY;
+ }
+
+ virtual int getOperandLatency(const InstrItineraryData *ItinData,
+ SDNode *DefNode, unsigned DefIdx,
+ SDNode *UseNode, unsigned UseIdx) const = 0;
+
+ /// getOperandLatency - Compute and return the use operand latency of a given
+ /// pair of def and use.
+ /// In most cases, the static scheduling itinerary was enough to determine the
+ /// operand latency. But it may not be possible for instructions with variable
+ /// number of defs / uses.
+ ///
+ /// This is a raw interface to the itinerary that may be directly overriden by
+ /// a target. Use computeOperandLatency to get the best estimate of latency.
+ virtual int getOperandLatency(const InstrItineraryData *ItinData,
+ const MachineInstr *DefMI, unsigned DefIdx,
+ const MachineInstr *UseMI,
+ unsigned UseIdx) const = 0;
+
+ /// computeOperandLatency - Compute and return the latency of the given data
+ /// dependent def and use when the operand indices are already known.
+ ///
+ /// FindMin may be set to get the minimum vs. expected latency.
+ unsigned computeOperandLatency(const InstrItineraryData *ItinData,
+ const MachineInstr *DefMI, unsigned DefIdx,
+ const MachineInstr *UseMI, unsigned UseIdx,
+ bool FindMin = false) const;
+
+ /// getInstrLatency - Compute the instruction latency of a given instruction.
+ /// If the instruction has higher cost when predicated, it's returned via
+ /// PredCost.
+ virtual unsigned getInstrLatency(const InstrItineraryData *ItinData,
+ const MachineInstr *MI,
+ unsigned *PredCost = 0) const = 0;
+
+ virtual int getInstrLatency(const InstrItineraryData *ItinData,
+ SDNode *Node) const = 0;
+
+ /// Return the default expected latency for a def based on it's opcode.
+ unsigned defaultDefLatency(const MCSchedModel *SchedModel,
+ const MachineInstr *DefMI) const;
+
+ int computeDefOperandLatency(const InstrItineraryData *ItinData,
+ const MachineInstr *DefMI, bool FindMin) const;
+
+ /// isHighLatencyDef - Return true if this opcode has high latency to its
+ /// result.
+ virtual bool isHighLatencyDef(int opc) const { return false; }
+
+ /// hasHighOperandLatency - Compute operand latency between a def of 'Reg'
+ /// and an use in the current loop, return true if the target considered
+ /// it 'high'. This is used by optimization passes such as machine LICM to
+ /// determine whether it makes sense to hoist an instruction out even in
+ /// high register pressure situation.
+ virtual
+ bool hasHighOperandLatency(const InstrItineraryData *ItinData,
+ const MachineRegisterInfo *MRI,
+ const MachineInstr *DefMI, unsigned DefIdx,
+ const MachineInstr *UseMI, unsigned UseIdx) const {
+ return false;
+ }
+
+ /// hasLowDefLatency - Compute operand latency of a def of 'Reg', return true
+ /// if the target considered it 'low'.
+ virtual
+ bool hasLowDefLatency(const InstrItineraryData *ItinData,
+ const MachineInstr *DefMI, unsigned DefIdx) const = 0;
+
+ /// verifyInstruction - Perform target specific instruction verification.
+ virtual
+ bool verifyInstruction(const MachineInstr *MI, StringRef &ErrInfo) const {
+ return true;
+ }
+
+ /// getExecutionDomain - Return the current execution domain and bit mask of
+ /// possible domains for instruction.
+ ///
+ /// Some micro-architectures have multiple execution domains, and multiple
+ /// opcodes that perform the same operation in different domains. For
+ /// example, the x86 architecture provides the por, orps, and orpd
+ /// instructions that all do the same thing. There is a latency penalty if a
+ /// register is written in one domain and read in another.
+ ///
+ /// This function returns a pair (domain, mask) containing the execution
+ /// domain of MI, and a bit mask of possible domains. The setExecutionDomain
+ /// function can be used to change the opcode to one of the domains in the
+ /// bit mask. Instructions whose execution domain can't be changed should
+ /// return a 0 mask.
+ ///
+ /// The execution domain numbers don't have any special meaning except domain
+ /// 0 is used for instructions that are not associated with any interesting
+ /// execution domain.
+ ///
+ virtual std::pair<uint16_t, uint16_t>
+ getExecutionDomain(const MachineInstr *MI) const {
+ return std::make_pair(0, 0);
}
+
+ /// setExecutionDomain - Change the opcode of MI to execute in Domain.
+ ///
+ /// The bit (1 << Domain) must be set in the mask returned from
+ /// getExecutionDomain(MI).
+ ///
+ virtual void setExecutionDomain(MachineInstr *MI, unsigned Domain) const {}
+
+
+ /// getPartialRegUpdateClearance - Returns the preferred minimum clearance
+ /// before an instruction with an unwanted partial register update.
+ ///
+ /// Some instructions only write part of a register, and implicitly need to
+ /// read the other parts of the register. This may cause unwanted stalls
+ /// preventing otherwise unrelated instructions from executing in parallel in
+ /// an out-of-order CPU.
+ ///
+ /// For example, the x86 instruction cvtsi2ss writes its result to bits
+ /// [31:0] of the destination xmm register. Bits [127:32] are unaffected, so
+ /// the instruction needs to wait for the old value of the register to become
+ /// available:
+ ///
+ /// addps %xmm1, %xmm0
+ /// movaps %xmm0, (%rax)
+ /// cvtsi2ss %rbx, %xmm0
+ ///
+ /// In the code above, the cvtsi2ss instruction needs to wait for the addps
+ /// instruction before it can issue, even though the high bits of %xmm0
+ /// probably aren't needed.
+ ///
+ /// This hook returns the preferred clearance before MI, measured in
+ /// instructions. Other defs of MI's operand OpNum are avoided in the last N
+ /// instructions before MI. It should only return a positive value for
+ /// unwanted dependencies. If the old bits of the defined register have
+ /// useful values, or if MI is determined to otherwise read the dependency,
+ /// the hook should return 0.
+ ///
+ /// The unwanted dependency may be handled by:
+ ///
+ /// 1. Allocating the same register for an MI def and use. That makes the
+ /// unwanted dependency identical to a required dependency.
+ ///
+ /// 2. Allocating a register for the def that has no defs in the previous N
+ /// instructions.
+ ///
+ /// 3. Calling breakPartialRegDependency() with the same arguments. This
+ /// allows the target to insert a dependency breaking instruction.
+ ///
+ virtual unsigned
+ getPartialRegUpdateClearance(const MachineInstr *MI, unsigned OpNum,
+ const TargetRegisterInfo *TRI) const {
+ // The default implementation returns 0 for no partial register dependency.
+ return 0;
+ }
+
+ /// breakPartialRegDependency - Insert a dependency-breaking instruction
+ /// before MI to eliminate an unwanted dependency on OpNum.
+ ///
+ /// If it wasn't possible to avoid a def in the last N instructions before MI
+ /// (see getPartialRegUpdateClearance), this hook will be called to break the
+ /// unwanted dependency.
+ ///
+ /// On x86, an xorps instruction can be used as a dependency breaker:
+ ///
+ /// addps %xmm1, %xmm0
+ /// movaps %xmm0, (%rax)
+ /// xorps %xmm0, %xmm0
+ /// cvtsi2ss %rbx, %xmm0
+ ///
+ /// An <imp-kill> operand should be added to MI if an instruction was
+ /// inserted. This ties the instructions together in the post-ra scheduler.
+ ///
+ virtual void
+ breakPartialRegDependency(MachineBasicBlock::iterator MI, unsigned OpNum,
+ const TargetRegisterInfo *TRI) const {}
+
+ /// Create machine specific model for scheduling.
+ virtual DFAPacketizer*
+ CreateTargetScheduleState(const TargetMachine*, const ScheduleDAG*) const {
+ return NULL;
+ }
+
+private:
+ int CallFrameSetupOpcode, CallFrameDestroyOpcode;
};
/// TargetInstrInfoImpl - This is the default implementation of
/// libcodegen, not in libtarget.
class TargetInstrInfoImpl : public TargetInstrInfo {
protected:
- TargetInstrInfoImpl(const TargetInstrDescriptor *desc, unsigned NumOpcodes)
- : TargetInstrInfo(desc, NumOpcodes) {}
+ TargetInstrInfoImpl(int CallFrameSetupOpcode = -1,
+ int CallFrameDestroyOpcode = -1)
+ : TargetInstrInfo(CallFrameSetupOpcode, CallFrameDestroyOpcode) {}
public:
- virtual MachineInstr *commuteInstruction(MachineInstr *MI) const;
+ virtual void ReplaceTailWithBranchTo(MachineBasicBlock::iterator OldInst,
+ MachineBasicBlock *NewDest) const;
+ virtual MachineInstr *commuteInstruction(MachineInstr *MI,
+ bool NewMI = false) const;
+ virtual bool findCommutedOpIndices(MachineInstr *MI, unsigned &SrcOpIdx1,
+ unsigned &SrcOpIdx2) const;
+ virtual bool canFoldMemoryOperand(const MachineInstr *MI,
+ const SmallVectorImpl<unsigned> &Ops) const;
+ virtual bool hasLoadFromStackSlot(const MachineInstr *MI,
+ const MachineMemOperand *&MMO,
+ int &FrameIndex) const;
+ virtual bool hasStoreToStackSlot(const MachineInstr *MI,
+ const MachineMemOperand *&MMO,
+ int &FrameIndex) const;
+ virtual bool isUnpredicatedTerminator(const MachineInstr *MI) const;
virtual bool PredicateInstruction(MachineInstr *MI,
- const std::vector<MachineOperand> &Pred) const;
-
+ const SmallVectorImpl<MachineOperand> &Pred) const;
+ virtual void reMaterialize(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ unsigned DestReg, unsigned SubReg,
+ const MachineInstr *Orig,
+ const TargetRegisterInfo &TRI) const;
+ virtual MachineInstr *duplicate(MachineInstr *Orig,
+ MachineFunction &MF) const;
+ virtual bool produceSameValue(const MachineInstr *MI0,
+ const MachineInstr *MI1,
+ const MachineRegisterInfo *MRI) const;
+ virtual bool isSchedulingBoundary(const MachineInstr *MI,
+ const MachineBasicBlock *MBB,
+ const MachineFunction &MF) const;
+
+ virtual int getOperandLatency(const InstrItineraryData *ItinData,
+ SDNode *DefNode, unsigned DefIdx,
+ SDNode *UseNode, unsigned UseIdx) const;
+
+ virtual int getInstrLatency(const InstrItineraryData *ItinData,
+ SDNode *Node) const;
+
+ virtual unsigned getNumMicroOps(const InstrItineraryData *ItinData,
+ const MachineInstr *MI) const;
+
+ virtual unsigned getInstrLatency(const InstrItineraryData *ItinData,
+ const MachineInstr *MI,
+ unsigned *PredCost = 0) const;
+
+ virtual
+ bool hasLowDefLatency(const InstrItineraryData *ItinData,
+ const MachineInstr *DefMI, unsigned DefIdx) const;
+
+ virtual int getOperandLatency(const InstrItineraryData *ItinData,
+ const MachineInstr *DefMI, unsigned DefIdx,
+ const MachineInstr *UseMI,
+ unsigned UseIdx) const;
+
+ bool usePreRAHazardRecognizer() const;
+
+ virtual ScheduleHazardRecognizer *
+ CreateTargetHazardRecognizer(const TargetMachine*, const ScheduleDAG*) const;
+
+ virtual ScheduleHazardRecognizer *
+ CreateTargetMIHazardRecognizer(const InstrItineraryData*,
+ const ScheduleDAG*) const;
+
+ virtual ScheduleHazardRecognizer *
+ CreateTargetPostRAHazardRecognizer(const InstrItineraryData*,
+ const ScheduleDAG*) const;
};
} // End llvm namespace
projects / oota-llvm.git / blobdiff