//
//===----------------------------------------------------------------------===//
//
-// 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/Target/TargetInstrDesc.h"
#include "llvm/CodeGen/MachineFunction.h"
-#include "llvm/Support/DataTypes.h"
-#include <vector>
-#include <cassert>
namespace llvm {
-class MachineInstr;
-class TargetMachine;
+class MCAsmInfo;
class TargetRegisterClass;
+class TargetRegisterInfo;
class LiveVariables;
class CalleeSavedInfo;
+class SDNode;
+class SelectionDAG;
template<class T> class SmallVectorImpl;
-//---------------------------------------------------------------------------
-// Data types used to define information about a single machine instruction
-//---------------------------------------------------------------------------
-
-typedef short MachineOpCode;
-typedef unsigned InstrSchedClass;
//---------------------------------------------------------------------------
-// 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
-// M_LOOK_UP_PTR_REG_CLASS - Set if this operand is a pointer value and it
-// requires a callback to look up its register class.
-const unsigned M_LOOK_UP_PTR_REG_CLASS = 1 << 0;
-
-/// M_PREDICATE_OPERAND - Set if this is one of the operands that made up of the
-/// predicate operand that controls an M_PREDICATED instruction.
-const unsigned M_PREDICATE_OPERAND = 1 << 1;
-
-/// M_OPTIONAL_DEF_OPERAND - Set if this operand is a optional def.
///
-const unsigned M_OPTIONAL_DEF_OPERAND = 1 << 2;
-
-namespace TOI {
- // Operand constraints: only "tied_to" for now.
- enum OperandConstraint {
- TIED_TO = 0 // Must be allocated the same register as.
- };
-}
-
-/// 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.
-};
-
-
-class TargetInstrDescriptor {
-public:
- MachineOpCode 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.
- InstrSchedClass 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;
-
-
- /// 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;
- }
-
-};
-
-
-//---------------------------------------------------------------------------
-///
-/// 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
+ const TargetInstrDesc *Descriptors; // Raw array to allow static init'n
+ unsigned NumOpcodes; // Number of entries in the desc array
TargetInstrInfo(const TargetInstrInfo &); // DO NOT IMPLEMENT
void operator=(const TargetInstrInfo &); // DO NOT IMPLEMENT
public:
- TargetInstrInfo(const TargetInstrDescriptor *desc, unsigned NumOpcodes);
+ TargetInstrInfo(const TargetInstrDesc *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
+ DBG_LABEL = 2,
+ EH_LABEL = 3,
+ GC_LABEL = 4,
+
+ /// KILL - This instruction is a noop that is used only to adjust the liveness
+ /// of registers. This can be useful when dealing with sub-registers.
+ KILL = 5,
+
+ /// EXTRACT_SUBREG - This instruction takes two operands: a register
+ /// that has subregisters, and a subregister index. It returns the
+ /// extracted subregister value. This is commonly used to implement
+ /// truncation operations on target architectures which support it.
+ EXTRACT_SUBREG = 6,
+
+ /// INSERT_SUBREG - This instruction takes three operands: a register
+ /// that has subregisters, a register providing an insert value, and a
+ /// subregister index. It returns the value of the first register with
+ /// the value of the second register inserted. The first register is
+ /// often defined by an IMPLICIT_DEF, as is commonly used to implement
+ /// anyext operations on target architectures which support it.
+ INSERT_SUBREG = 7,
+
+ /// IMPLICIT_DEF - This is the MachineInstr-level equivalent of undef.
+ IMPLICIT_DEF = 8,
+
+ /// SUBREG_TO_REG - This instruction is similar to INSERT_SUBREG except
+ /// that the first operand is an immediate integer constant. This constant
+ /// is often zero, as is commonly used to implement zext operations on
+ /// target architectures which support it, such as with x86-64 (with
+ /// zext from i32 to i64 via implicit zero-extension).
+ SUBREG_TO_REG = 9,
+
+ /// COPY_TO_REGCLASS - This instruction is a placeholder for a plain
+ /// register-to-register copy into a specific register class. This is only
+ /// used between instruction selection and MachineInstr creation, before
+ /// virtual registers have been created for all the instructions, and it's
+ /// only needed in cases where the register classes implied by the
+ /// instructions are insufficient. The actual MachineInstrs to perform
+ /// the copy are emitted with the TargetInstrInfo::copyRegToReg hook.
+ COPY_TO_REGCLASS = 10
};
unsigned getNumOpcodes() const { return NumOpcodes; }
/// get - Return the machine instruction descriptor that corresponds to the
/// specified instruction opcode.
///
- const TargetInstrDescriptor& get(MachineOpCode Opcode) const {
- assert((unsigned)Opcode < NumOpcodes);
- return desc[Opcode];
- }
-
- const char *getName(MachineOpCode Opcode) const {
- return get(Opcode).Name;
- }
-
- int getNumOperands(MachineOpCode Opcode) const {
- return get(Opcode).numOperands;
- }
-
- int getNumDefs(MachineOpCode Opcode) const {
- return get(Opcode).numDefs;
- }
-
- InstrSchedClass getSchedClass(MachineOpCode Opcode) const {
- return get(Opcode).schedClass;
- }
-
- const unsigned *getImplicitUses(MachineOpCode Opcode) const {
- return get(Opcode).ImplicitUses;
- }
-
- const unsigned *getImplicitDefs(MachineOpCode Opcode) const {
- return get(Opcode).ImplicitDefs;
- }
-
-
- //
- // Query instruction class flags according to the machine-independent
- // flags listed above.
- //
- bool isReturn(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_RET_FLAG;
- }
-
- bool isCommutableInstr(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_COMMUTABLE;
- }
- bool isTerminatorInstr(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_TERMINATOR_FLAG;
- }
-
- bool isBranch(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_BRANCH_FLAG;
- }
-
- bool isIndirectBranch(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_INDIRECT_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(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_BARRIER_FLAG;
- }
-
- bool isCall(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_CALL_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(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_MAY_STORE_FLAG;
- }
-
- /// hasDelaySlot - Returns true if the specified instruction has a delay slot
- /// which must be filled by the code generator.
- bool hasDelaySlot(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_DELAY_SLOT_FLAG;
- }
-
- /// usesCustomDAGSchedInsertionHook - Return true if this instruction requires
- /// custom insertion support when the DAG scheduler is inserting it into a
- /// machine basic block.
- bool usesCustomDAGSchedInsertionHook(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_USES_CUSTOM_DAG_SCHED_INSERTION;
- }
-
- bool hasVariableOperands(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_VARIABLE_OPS;
- }
-
- bool isPredicable(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_PREDICABLE;
- }
-
- bool isNotDuplicable(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_NOT_DUPLICABLE;
- }
-
- bool hasOptionalDef(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_HAS_OPTIONAL_DEF;
+ const TargetInstrDesc &get(unsigned Opcode) const {
+ assert(Opcode < NumOpcodes && "Invalid opcode!");
+ return Descriptors[Opcode];
}
/// 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->getInstrDescriptor()->Flags & M_REMATERIALIZIBLE) &&
- isReallyTriviallyReMaterializable(MI);
+ bool isTriviallyReMaterializable(const MachineInstr *MI,
+ AliasAnalysis *AA = 0) const {
+ return MI->getOpcode() == 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->getInstrDescriptor();
- 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(MachineOpCode Opcode, unsigned OpNum,
- TOI::OperandConstraint Constraint) const {
- return get(Opcode).getOperandConstraint(OpNum, Constraint);
+ /// isMoveInstr - Return true if the instruction is a register to register
+ /// move and return the source and dest operands and their sub-register
+ /// indices by reference.
+ virtual bool isMoveInstr(const MachineInstr& MI,
+ unsigned& SrcReg, unsigned& DstReg,
+ unsigned& SrcSubIdx, unsigned& DstSubIdx) const {
+ return false;
}
- /// 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 {
+ /// isIdentityCopy - Return true if the instruction is a copy (or
+ /// extract_subreg, insert_subreg, subreg_to_reg) where the source and
+ /// destination registers are the same.
+ bool isIdentityCopy(const MachineInstr &MI) const {
+ unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
+ if (isMoveInstr(MI, SrcReg, DstReg, SrcSubIdx, DstSubIdx) &&
+ SrcReg == DstReg)
+ return true;
+
+ if (MI.getOpcode() == TargetInstrInfo::EXTRACT_SUBREG &&
+ MI.getOperand(0).getReg() == MI.getOperand(1).getReg())
+ return true;
+
+ if ((MI.getOpcode() == TargetInstrInfo::INSERT_SUBREG ||
+ MI.getOpcode() == TargetInstrInfo::SUBREG_TO_REG) &&
+ MI.getOperand(0).getReg() == MI.getOperand(2).getReg())
+ return true;
return false;
}
/// 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. 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,
+ int &FrameIndex) const {
return 0;
}
/// 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. If not, return false. Unlike
+ /// isStoreToStackSlot, this returns true for any instructions that
+ /// loads from the stack. This is just a hint, as some cases may be
+ /// missed.
+ virtual bool hasStoreToStackSlot(const MachineInstr *MI,
+ int &FrameIndex) const {
+ return 0;
+ }
+
+ /// reMaterialize - Re-issue the specified 'original' instruction at the
+ /// specific location targeting a new destination register.
+ virtual void reMaterialize(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ unsigned DestReg, unsigned SubIdx,
+ const MachineInstr *Orig,
+ const TargetRegisterInfo *TRI) 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;
}
/// return a new machine instruction. If an instruction cannot commute, it
/// can also return null.
///
- virtual MachineInstr *commuteInstruction(MachineInstr *MI) const = 0;
+ /// If NewMI is true, then a new machine instruction must be created.
+ ///
+ 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 true if the instruction
+ /// is not in a form which this routine understands.
+ virtual bool findCommutedOpIndices(MachineInstr *MI, unsigned &SrcOpIdx1,
+ unsigned &SrcOpIdx2) const = 0;
+
+ /// isIdentical - Return true if two instructions are identical. This differs
+ /// from MachineInstr::isIdenticalTo() in that it does not require the
+ /// virtual destination registers to be the same. This is used by MachineLICM
+ /// and other MI passes to perform CSE.
+ virtual bool isIdentical(const MachineInstr *MI,
+ const MachineInstr *Other,
+ const MachineRegisterInfo *MRI) 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
/// 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
+ /// 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;
}
-
- /// 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 {
+ const SmallVectorImpl<MachineOperand> &Cond) const {
assert(0 && "Target didn't implement TargetInstrInfo::InsertBranch!");
return 0;
}
- /// copyRegToReg - Add a copy between a pair of registers
- virtual void copyRegToReg(MachineBasicBlock &MBB,
+ /// copyRegToReg - Emit instructions to copy between a pair of registers. It
+ /// returns false if the target does not how to copy between the specified
+ /// registers.
+ virtual bool 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!");
+ return false;
}
+ /// 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,
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!");
- }
-
+ /// 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
return false;
}
+ /// 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.
+ MachineInstr* foldMemoryOperand(MachineFunction &MF,
+ MachineInstr* 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.
+ MachineInstr* foldMemoryOperand(MachineFunction &MF,
+ MachineInstr* 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;
+ }
+
+ /// 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(const MachineInstr *MI,
+ const SmallVectorImpl<unsigned> &Ops) const {
+ return false;
+ }
+
+ /// 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{
+ return false;
+ }
+
+ virtual bool unfoldMemoryOperand(SelectionDAG &DAG, SDNode *N,
+ SmallVectorImpl<SDNode*> &NewNodes) 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. 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,
+ 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 {
+ virtual bool BlockHasNoFallThrough(const MachineBasicBlock &MBB) 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();
- }
-
+ MachineBasicBlock::iterator MI) const;
+
/// isPredicated - Returns true if the instruction is already predicated.
///
virtual bool isPredicated(const MachineInstr *MI) const {
/// 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;
+ }
+
+ /// GetInstSize - Returns the size of the specified Instruction.
+ ///
+ virtual unsigned GetInstSizeInBytes(const MachineInstr *MI) const {
+ assert(0 && "Target didn't implement TargetInstrInfo::GetInstSize!");
+ return 0;
+ }
+
+ /// GetFunctionSizeInBytes - Returns the size of the specified
+ /// MachineFunction.
+ ///
+ virtual unsigned GetFunctionSizeInBytes(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;
+
+ /// isProfitableToDuplicateIndirectBranch - Returns true if tail duplication
+ /// is especially profitable for indirect branches.
+ virtual bool isProfitableToDuplicateIndirectBranch() const { return false; }
};
/// TargetInstrInfoImpl - This is the default implementation of
/// libcodegen, not in libtarget.
class TargetInstrInfoImpl : public TargetInstrInfo {
protected:
- TargetInstrInfoImpl(const TargetInstrDescriptor *desc, unsigned NumOpcodes)
+ TargetInstrInfoImpl(const TargetInstrDesc *desc, unsigned NumOpcodes)
: TargetInstrInfo(desc, NumOpcodes) {}
public:
- virtual MachineInstr *commuteInstruction(MachineInstr *MI) const;
+ virtual MachineInstr *commuteInstruction(MachineInstr *MI,
+ bool NewMI = false) const;
+ virtual bool findCommutedOpIndices(MachineInstr *MI, unsigned &SrcOpIdx1,
+ unsigned &SrcOpIdx2) 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 bool isIdentical(const MachineInstr *MI,
+ const MachineInstr *Other,
+ const MachineRegisterInfo *MRI) const;
+
+ virtual unsigned GetFunctionSizeInBytes(const MachineFunction &MF) const;
};
} // End llvm namespace
projects / oota-llvm.git / blobdiff