//===-- llvm/Target/TargetInstrInfo.h - Instruction Info --------*- C++ -*-===//
-//
+//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+//
//===----------------------------------------------------------------------===//
//
// This file describes the target machine instructions to the code generator.
#define LLVM_TARGET_TARGETINSTRINFO_H
#include "llvm/CodeGen/MachineBasicBlock.h"
-#include "Support/DataTypes.h"
+#include "llvm/Support/DataTypes.h"
#include <vector>
#include <cassert>
class Constant;
class Function;
class MachineCodeForInstruction;
+class TargetRegisterClass;
//---------------------------------------------------------------------------
// Data types used to define information about a single machine instruction
//---------------------------------------------------------------------------
// struct TargetInstrDescriptor:
-// Predefined information about each machine instruction.
-// Designed to initialized statically.
+// Predefined information about each machine instruction.
+// Designed to initialized statically.
//
-const unsigned M_NOP_FLAG = 1 << 0;
-const unsigned M_BRANCH_FLAG = 1 << 1;
-const unsigned M_CALL_FLAG = 1 << 2;
-const unsigned M_RET_FLAG = 1 << 3;
-const unsigned M_BARRIER_FLAG = 1 << 4;
-const unsigned M_CC_FLAG = 1 << 6;
-const unsigned M_LOAD_FLAG = 1 << 10;
-const unsigned M_STORE_FLAG = 1 << 12;
-const unsigned M_DUMMY_PHI_FLAG = 1 << 13;
-const unsigned M_PSEUDO_FLAG = 1 << 14; // Pseudo instruction
-// 3-addr instructions which really work like 2-addr ones, eg. X86 add/sub
-const unsigned M_2_ADDR_FLAG = 1 << 15;
+const unsigned M_NOP_FLAG = 1 << 0;
+const unsigned M_BRANCH_FLAG = 1 << 1;
+const unsigned M_CALL_FLAG = 1 << 2;
+const unsigned M_RET_FLAG = 1 << 3;
+const unsigned M_BARRIER_FLAG = 1 << 4;
+const unsigned M_DELAY_SLOT_FLAG = 1 << 5;
+const unsigned M_CC_FLAG = 1 << 6;
+const unsigned M_LOAD_FLAG = 1 << 7;
+const unsigned M_STORE_FLAG = 1 << 8;
+
+// M_2_ADDR_FLAG - 3-addr instructions which really work like 2-addr ones.
+const unsigned M_2_ADDR_FLAG = 1 << 9;
+
+// M_CONVERTIBLE_TO_3_ADDR - This is a M_2_ADDR_FLAG 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 << 10;
+
+// 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 << 11;
// 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 << 16;
+const unsigned M_TERMINATOR_FLAG = 1 << 12;
+
+// 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 << 13;
-struct TargetInstrDescriptor {
+/// 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 of the operand if the
+ /// operand is a register. If not, this contains null.
+ const TargetRegisterClass *RegClass;
+
+ /// Currently no other information.
+};
+
+
+class TargetInstrDescriptor {
+public:
const char * Name; // Assembly language mnemonic for the opcode.
int numOperands; // Number of args; -1 if variable #args
int resultPos; // Position of the result; -1 if no result
unsigned maxImmedConst; // Largest +ve constant in IMMED field or 0.
- bool immedIsSignExtended; // Is IMMED field sign-extended? If so,
+ bool immedIsSignExtended; // Is IMMED field sign-extended? If so,
// smallest -ve value is -(maxImmedConst+1).
unsigned numDelaySlots; // Number of delay slots after instruction
unsigned latency; // Latency in machine cycles
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.
};
//---------------------------------------------------------------------------
-///
+///
/// TargetInstrInfo - Interface to description of machine instructions
-///
+///
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
public:
// Invariant: All instruction sets use opcode #0 as the PHI instruction
enum { PHI = 0 };
-
+
unsigned getNumOpcodes() const { return NumOpcodes; }
-
+
/// get - Return the machine instruction descriptor that corresponds to the
/// specified instruction opcode.
///
const char *getName(MachineOpCode Opcode) const {
return get(Opcode).Name;
}
-
+
int getNumOperands(MachineOpCode Opcode) const {
return get(Opcode).numOperands;
}
-
InstrSchedClass getSchedClass(MachineOpCode Opcode) const {
return get(Opcode).schedClass;
}
//
// 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 isPseudoInstr(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_PSEUDO_FLAG;
- }
bool isTwoAddrInstr(MachineOpCode Opcode) const {
return get(Opcode).Flags & M_2_ADDR_FLAG;
}
bool isTerminatorInstr(unsigned Opcode) const {
return get(Opcode).Flags & M_TERMINATOR_FLAG;
}
+
+ bool isBranch(MachineOpCode Opcode) const {
+ return get(Opcode).Flags & M_BRANCH_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;
+ }
+ bool isLoad(MachineOpCode Opcode) const {
+ return get(Opcode).Flags & M_LOAD_FLAG;
+ }
+ bool isStore(MachineOpCode Opcode) const {
+ return get(Opcode).Flags & M_STORE_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(unsigned Opcode) const {
+ return get(Opcode).Flags & M_USES_CUSTOM_DAG_SCHED_INSERTION;
+ }
- //
- // Return true if the instruction is a register to register move and
- // leave the source and dest operands in the passed parameters.
- //
+ /// 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 {
return false;
}
- //
- // Insert a goto (unconditional branch) sequence to MBB, right
- // before MBBI
- virtual void insertGoto(const MachineBasicBlock& MBB,
- MachineBasicBlock::iterator MBBI) const {
+ /// 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 a true
+ /// three-address instruction on demand. This allows the X86 target (for
+ /// example) to convert ADD and SHL instructions into LEA instructions if they
+ /// would require register copies due to two-addressness.
+ ///
+ /// This method returns a null pointer if the transformation cannot be
+ /// performed, otherwise it returns the new instruction.
+ ///
+ virtual MachineInstr *convertToThreeAddress(MachineInstr *TA) 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;
+
+ /// Insert a goto (unconditional branch) sequence to TMBB, at the
+ /// end of MBB
+ virtual void insertGoto(MachineBasicBlock& MBB,
+ MachineBasicBlock& TMBB) const {
assert(0 && "Target didn't implement insertGoto!");
}
- //
- // Reverses the branch condition of the MachineInstr pointed by
- // MI. The instruction is replaced and the new MI is returned.
+ /// Reverses the branch condition of the MachineInstr pointed by
+ /// MI. The instruction is replaced and the new MI is returned.
virtual MachineBasicBlock::iterator
reverseBranchCondition(MachineBasicBlock::iterator MI) const {
assert(0 && "Target didn't implement reverseBranchCondition!");
+ abort();
+ return MI;
}
+
//-------------------------------------------------------------------------
// Code generation support for creating individual machine instructions
//
//-------------------------------------------------------------------------
- int getResultPos(MachineOpCode Opcode) const {
- return get(Opcode).resultPos;
- }
unsigned getNumDelaySlots(MachineOpCode Opcode) const {
return get(Opcode).numDelaySlots;
}
bool isNop(MachineOpCode Opcode) const {
return get(Opcode).Flags & M_NOP_FLAG;
}
- bool isBranch(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_BRANCH_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;
- }
- bool isLoad(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_LOAD_FLAG;
- }
- bool isStore(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_STORE_FLAG;
- }
- bool isDummyPhiInstr(MachineOpCode Opcode) const {
- return get(Opcode).Flags & M_DUMMY_PHI_FLAG;
+
+ /// hasDelaySlot - Returns true if the specified instruction has a delay slot
+ /// which must be filled by the code generator.
+ bool hasDelaySlot(unsigned Opcode) const {
+ return get(Opcode).Flags & M_DELAY_SLOT_FLAG;
}
virtual bool hasResultInterlock(MachineOpCode Opcode) const {
return true;
}
- //
+ //
// Latencies for individual instructions and instruction pairs
- //
+ //
virtual int minLatency(MachineOpCode Opcode) const {
return get(Opcode).latency;
}
-
+
virtual int maxLatency(MachineOpCode Opcode) const {
return get(Opcode).latency;
}
//
// Which operand holds an immediate constant? Returns -1 if none
- //
+ //
virtual int getImmedConstantPos(MachineOpCode Opcode) const {
return -1; // immediate position is machine specific, so say -1 == "none"
}
-
+
// Check if the specified constant fits in the immediate field
// of this machine instruction
- //
+ //
virtual bool constantFitsInImmedField(MachineOpCode Opcode,
- int64_t intValue) const;
-
+ int64_t intValue) const;
+
// Return the largest positive constant that can be held in the IMMED field
// of this machine instruction.
// isSignExtended is set to true if the value is sign-extended before use
// (this is true for all immediate fields in SPARC instructions).
// Return 0 if the instruction has no IMMED field.
- //
+ //
virtual uint64_t maxImmedConstant(MachineOpCode Opcode,
- bool &isSignExtended) const {
+ bool &isSignExtended) const {
isSignExtended = get(Opcode).immedIsSignExtended;
return get(Opcode).maxImmedConst;
}