path: root/include/llvm/CodeGen/ISDOpcodes.h

//===-- llvm/CodeGen/ISDOpcodes.h - CodeGen opcodes -------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file declares codegen opcodes and related utilities.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CODEGEN_ISDOPCODES_H
#define LLVM_CODEGEN_ISDOPCODES_H

namespace llvm {

/// ISD namespace - This namespace contains an enum which represents all of the
/// SelectionDAG node types and value types.
///
namespace ISD {

  //===--------------------------------------------------------------------===//
  /// ISD::NodeType enum - This enum defines the target-independent operators
  /// for a SelectionDAG.
  ///
  /// Targets may also define target-dependent operator codes for SDNodes. For
  /// example, on x86, these are the enum values in the X86ISD namespace.
  /// Targets should aim to use target-independent operators to model their
  /// instruction sets as much as possible, and only use target-dependent
  /// operators when they have special requirements.
  ///
  /// Finally, during and after selection proper, SNodes may use special
  /// operator codes that correspond directly with MachineInstr opcodes. These
  /// are used to represent selected instructions. See the isMachineOpcode()
  /// and getMachineOpcode() member functions of SDNode.
  ///
  enum NodeType {
    /// DELETED_NODE - This is an illegal value that is used to catch
    /// errors.  This opcode is not a legal opcode for any node.
    DELETED_NODE,

    /// EntryToken - This is the marker used to indicate the start of a region.
    EntryToken,

    /// TokenFactor - This node takes multiple tokens as input and produces a
    /// single token result. This is used to represent the fact that the operand
    /// operators are independent of each other.
    TokenFactor,

    /// AssertSext, AssertZext - These nodes record if a register contains a
    /// value that has already been zero or sign extended from a narrower type.
    /// These nodes take two operands.  The first is the node that has already
    /// been extended, and the second is a value type node indicating the width
    /// of the extension
    AssertSext, AssertZext,

    /// Various leaf nodes.
    BasicBlock, VALUETYPE, CONDCODE, Register, RegisterMask,
    Constant, ConstantFP,
    GlobalAddress, GlobalTLSAddress, FrameIndex,
    JumpTable, ConstantPool, ExternalSymbol, BlockAddress,

    /// The address of the GOT
    GLOBAL_OFFSET_TABLE,

    /// FRAMEADDR, RETURNADDR - These nodes represent llvm.frameaddress and
    /// llvm.returnaddress on the DAG.  These nodes take one operand, the index
    /// of the frame or return address to return.  An index of zero corresponds
    /// to the current function's frame or return address, an index of one to
    /// the parent's frame or return address, and so on.
    FRAMEADDR, RETURNADDR,

    /// FRAME_TO_ARGS_OFFSET - This node represents offset from frame pointer to
    /// first (possible) on-stack argument. This is needed for correct stack
    /// adjustment during unwind.
    FRAME_TO_ARGS_OFFSET,

    /// RESULT, OUTCHAIN = EXCEPTIONADDR(INCHAIN) - This node represents the
    /// address of the exception block on entry to an landing pad block.
    EXCEPTIONADDR,

    /// RESULT, OUTCHAIN = LSDAADDR(INCHAIN) - This node represents the
    /// address of the Language Specific Data Area for the enclosing function.
    LSDAADDR,

    /// RESULT, OUTCHAIN = EHSELECTION(INCHAIN, EXCEPTION) - This node
    /// represents the selection index of the exception thrown.
    EHSELECTION,

    /// OUTCHAIN = EH_RETURN(INCHAIN, OFFSET, HANDLER) - This node represents
    /// 'eh_return' gcc dwarf builtin, which is used to return from
    /// exception. The general meaning is: adjust stack by OFFSET and pass
    /// execution to HANDLER. Many platform-related details also :)
    EH_RETURN,

    /// RESULT, OUTCHAIN = EH_SJLJ_SETJMP(INCHAIN, buffer)
    /// This corresponds to the eh.sjlj.setjmp intrinsic.
    /// It takes an input chain and a pointer to the jump buffer as inputs
    /// and returns an outchain.
    EH_SJLJ_SETJMP,

    /// OUTCHAIN = EH_SJLJ_LONGJMP(INCHAIN, buffer)
    /// This corresponds to the eh.sjlj.longjmp intrinsic.
    /// It takes an input chain and a pointer to the jump buffer as inputs
    /// and returns an outchain.
    EH_SJLJ_LONGJMP,

    /// TargetConstant* - Like Constant*, but the DAG does not do any folding,
    /// simplification, or lowering of the constant. They are used for constants
    /// which are known to fit in the immediate fields of their users, or for
    /// carrying magic numbers which are not values which need to be
    /// materialized in registers.
    TargetConstant,
    TargetConstantFP,

    /// TargetGlobalAddress - Like GlobalAddress, but the DAG does no folding or
    /// anything else with this node, and this is valid in the target-specific
    /// dag, turning into a GlobalAddress operand.
    TargetGlobalAddress,
    TargetGlobalTLSAddress,
    TargetFrameIndex,
    TargetJumpTable,
    TargetConstantPool,
    TargetExternalSymbol,
    TargetBlockAddress,

    /// TargetIndex - Like a constant pool entry, but with completely
    /// target-dependent semantics. Holds target flags, a 32-bit index, and a
    /// 64-bit index. Targets can use this however they like.
    TargetIndex,

    /// RESULT = INTRINSIC_WO_CHAIN(INTRINSICID, arg1, arg2, ...)
    /// This node represents a target intrinsic function with no side effects.
    /// The first operand is the ID number of the intrinsic from the
    /// llvm::Intrinsic namespace.  The operands to the intrinsic follow.  The
    /// node returns the result of the intrinsic.
    INTRINSIC_WO_CHAIN,

    /// RESULT,OUTCHAIN = INTRINSIC_W_CHAIN(INCHAIN, INTRINSICID, arg1, ...)
    /// This node represents a target intrinsic function with side effects that
    /// returns a result.  The first operand is a chain pointer.  The second is
    /// the ID number of the intrinsic from the llvm::Intrinsic namespace.  The
    /// operands to the intrinsic follow.  The node has two results, the result
    /// of the intrinsic and an output chain.
    INTRINSIC_W_CHAIN,

    /// OUTCHAIN = INTRINSIC_VOID(INCHAIN, INTRINSICID, arg1, arg2, ...)
    /// This node represents a target intrinsic function with side effects that
    /// does not return a result.  The first operand is a chain pointer.  The
    /// second is the ID number of the intrinsic from the llvm::Intrinsic
    /// namespace.  The operands to the intrinsic follow.
    INTRINSIC_VOID,

    /// CopyToReg - This node has three operands: a chain, a register number to
    /// set to this value, and a value.
    CopyToReg,

    /// CopyFromReg - This node indicates that the input value is a virtual or
    /// physical register that is defined outside of the scope of this
    /// SelectionDAG.  The register is available from the RegisterSDNode object.
    CopyFromReg,

    /// UNDEF - An undefined node.
    UNDEF,

    /// EXTRACT_ELEMENT - This is used to get the lower or upper (determined by
    /// a Constant, which is required to be operand #1) half of the integer or
    /// float value specified as operand #0.  This is only for use before
    /// legalization, for values that will be broken into multiple registers.
    EXTRACT_ELEMENT,

    /// BUILD_PAIR - This is the opposite of EXTRACT_ELEMENT in some ways.
    /// Given two values of the same integer value type, this produces a value
    /// twice as big.  Like EXTRACT_ELEMENT, this can only be used before
    /// legalization.
    BUILD_PAIR,

    /// MERGE_VALUES - This node takes multiple discrete operands and returns
    /// them all as its individual results.  This nodes has exactly the same
    /// number of inputs and outputs. This node is useful for some pieces of the
    /// code generator that want to think about a single node with multiple
    /// results, not multiple nodes.
    MERGE_VALUES,

    /// Simple integer binary arithmetic operators.
    ADD, SUB, MUL, SDIV, UDIV, SREM, UREM,

    /// SMUL_LOHI/UMUL_LOHI - Multiply two integers of type iN, producing
    /// a signed/unsigned value of type i[2*N], and return the full value as
    /// two results, each of type iN.
    SMUL_LOHI, UMUL_LOHI,

    /// SDIVREM/UDIVREM - Divide two integers and produce both a quotient and
    /// remainder result.
    SDIVREM, UDIVREM,

    /// CARRY_FALSE - This node is used when folding other nodes,
    /// like ADDC/SUBC, which indicate the carry result is always false.
    CARRY_FALSE,

    /// Carry-setting nodes for multiple precision addition and subtraction.
    /// These nodes take two operands of the same value type, and produce two
    /// results.  The first result is the normal add or sub result, the second
    /// result is the carry flag result.
    ADDC, SUBC,

    /// Carry-using nodes for multiple precision addition and subtraction. These
    /// nodes take three operands: The first two are the normal lhs and rhs to
    /// the add or sub, and the third is the input carry flag.  These nodes
    /// produce two results; the normal result of the add or sub, and the output
    /// carry flag.  These nodes both read and write a carry flag to allow them
    /// to them to be chained together for add and sub of arbitrarily large
    /// values.
    ADDE, SUBE,

    /// RESULT, BOOL = [SU]ADDO(LHS, RHS) - Overflow-aware nodes for addition.
    /// These nodes take two operands: the normal LHS and RHS to the add. They
    /// produce two results: the normal result of the add, and a boolean that
    /// indicates if an overflow occurred (*not* a flag, because it may be store
    /// to memory, etc.).  If the type of the boolean is not i1 then the high
    /// bits conform to getBooleanContents.
    /// These nodes are generated from llvm.[su]add.with.overflow intrinsics.
    SADDO, UADDO,

    /// Same for subtraction.
    SSUBO, USUBO,

    /// Same for multiplication.
    SMULO, UMULO,

    /// Simple binary floating point operators.
    FADD, FSUB, FMUL, FMA, FDIV, FREM,

    /// FCOPYSIGN(X, Y) - Return the value of X with the sign of Y.  NOTE: This
    /// DAG node does not require that X and Y have the same type, just that the
    /// are both floating point.  X and the result must have the same type.
    /// FCOPYSIGN(f32, f64) is allowed.
    FCOPYSIGN,

    /// INT = FGETSIGN(FP) - Return the sign bit of the specified floating point
    /// value as an integer 0/1 value.
    FGETSIGN,

    /// BUILD_VECTOR(ELT0, ELT1, ELT2, ELT3,...) - Return a vector with the
    /// specified, possibly variable, elements.  The number of elements is
    /// required to be a power of two.  The types of the operands must all be
    /// the same and must match the vector element type, except that integer
    /// types are allowed to be larger than the element type, in which case
    /// the operands are implicitly truncated.
    BUILD_VECTOR,

    /// INSERT_VECTOR_ELT(VECTOR, VAL, IDX) - Returns VECTOR with the element
    /// at IDX replaced with VAL.  If the type of VAL is larger than the vector
    /// element type then VAL is truncated before replacement.
    INSERT_VECTOR_ELT,

    /// EXTRACT_VECTOR_ELT(VECTOR, IDX) - Returns a single element from VECTOR
    /// identified by the (potentially variable) element number IDX.  If the
    /// return type is an integer type larger than the element type of the
    /// vector, the result is extended to the width of the return type.
    EXTRACT_VECTOR_ELT,

    /// CONCAT_VECTORS(VECTOR0, VECTOR1, ...) - Given a number of values of
    /// vector type with the same length and element type, this produces a
    /// concatenated vector result value, with length equal to the sum of the
    /// lengths of the input vectors.
    CONCAT_VECTORS,

    /// INSERT_SUBVECTOR(VECTOR1, VECTOR2, IDX) - Returns a vector
    /// with VECTOR2 inserted into VECTOR1 at the (potentially
    /// variable) element number IDX, which must be a multiple of the
    /// VECTOR2 vector length.  The elements of VECTOR1 starting at
    /// IDX are overwritten with VECTOR2.  Elements IDX through
    /// vector_length(VECTOR2) must be valid VECTOR1 indices.
    INSERT_SUBVECTOR,

    /// EXTRACT_SUBVECTOR(VECTOR, IDX) - Returns a subvector from VECTOR (an
    /// vector value) starting with the element number IDX, which must be a
    /// constant multiple of the result vector length.
    EXTRACT_SUBVECTOR,

    /// VECTOR_SHUFFLE(VEC1, VEC2) - Returns a vector, of the same type as
    /// VEC1/VEC2.  A VECTOR_SHUFFLE node also contains an array of constant int
    /// values that indicate which value (or undef) each result element will
    /// get.  These constant ints are accessible through the
    /// ShuffleVectorSDNode class.  This is quite similar to the Altivec
    /// 'vperm' instruction, except that the indices must be constants and are
    /// in terms of the element size of VEC1/VEC2, not in terms of bytes.
    VECTOR_SHUFFLE,

    /// SCALAR_TO_VECTOR(VAL) - This represents the operation of loading a
    /// scalar value into element 0 of the resultant vector type.  The top
    /// elements 1 to N-1 of the N-element vector are undefined.  The type
    /// of the operand must match the vector element type, except when they
    /// are integer types.  In this case the operand is allowed to be wider
    /// than the vector element type, and is implicitly trun