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+/* This file contains the definitions and documentation for the
+   Register Transfer Expressions (rtx's) that make up the
+   Register Transfer Language (rtl) used in the Back End of the GNU compiler.
+   Copyright (C) 1987-1991 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU CC is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU CC; see the file COPYING.  If not, write to
+the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+
+/* Expression definitions and descriptions for all targets are in this file.
+   Some will not be used for some targets.
+
+   The fields in the cpp macro call "DEF_RTL_EXPR()"
+   are used to create declarations in the C source of the compiler.
+
+   The fields are:
+
+   1.  The internal name of the rtx used in the C source.
+   It is a tag in the enumeration "enum rtx_code" defined in "rtl.h".
+   By convention these are in UPPER_CASE.
+
+   2.  The name of the rtx in the external ASCII format read by
+   read_rtx(), and printed by print_rtx().
+   These names are stored in rtx_name[].
+   By convention these are the internal (field 1) names in lower_case.
+
+   3.  The print format, and type of each rtx->fld[] (field) in this rtx.
+   These formats are stored in rtx_format[].
+   The meaning of the formats is documented in front of this array in rtl.c
+   
+   4.  The class of the rtx.  These are stored in rtx_class and are accessed
+   via the GET_RTX_CLASS macro.  They are defined as follows:
+
+     "o" an rtx code that can be used to represent an object (e.g, REG, MEM)
+     "<" an rtx code for a comparison (e.g, EQ, NE, LT)
+     "1" an rtx code for a unary arithmetic expression (e.g, NEG, NOT)
+     "c" an rtx code for a commutative binary operation (e.g,, PLUS, MULT)
+     "3" an rtx code for a non-bitfield three input operation (IF_THEN_ELSE)
+     "2" an rtx code for a non-commutative binary operation (e.g., MINUS, DIV)
+     "b" an rtx code for a bit-field operation (ZERO_EXTRACT, SIGN_EXTRACT)
+     "i" an rtx code for a machine insn (INSN, JUMP_INSN, CALL_INSN)
+     "m" an rtx code for something that matches in insns (e.g, MATCH_DUP)
+     "x" everything else
+     
+   */
+
+/* ---------------------------------------------------------------------
+   Expressions (and "meta" expressions) used for structuring the
+   rtl representation of a program.
+   --------------------------------------------------------------------- */
+
+/* an expression code name unknown to the reader */
+DEF_RTL_EXPR(UNKNOWN, "UnKnown", "*", 'x')
+
+/* (NIL) is used by rtl reader and printer to represent a null pointer.  */
+
+DEF_RTL_EXPR(NIL, "nil", "*", 'x')
+
+/* ---------------------------------------------------------------------
+   Expressions used in constructing lists.
+   --------------------------------------------------------------------- */
+
+/* a linked list of expressions */
+DEF_RTL_EXPR(EXPR_LIST, "expr_list", "ee", 'x')
+
+/* a linked list of instructions.
+   The insns are represented in print by their uids.  */
+DEF_RTL_EXPR(INSN_LIST, "insn_list", "ue", 'x')
+
+/* ----------------------------------------------------------------------
+   Expression types for machine descripions.
+   These do not appear in actual rtl code in the compiler.
+   ---------------------------------------------------------------------- */
+
+/* Appears only in machine descriptions.
+   Means use the function named by the second arg (the string)
+   as a predicate; if matched, store the structure that was matched
+   in the operand table at index specified by the first arg (the integer).
+   If the second arg is the null string, the structure is just stored.
+
+   A third string argument indicates to the register allocator restrictions
+   on where the operand can be allocated.
+
+   If the target needs no restriction on any instruction this field should
+   be the null string.
+
+   The string is prepended by:
+   '=' to indicate the operand is only written to.
+   '+' to indicate the operand is both read and written to.
+
+   Each character in the string represents an allocatable class for an operand.
+   'g' indicates the operand can be any valid class.
+   'i' indicates the operand can be immediate (in the instruction) data.
+   'r' indicates the operand can be in a register.
+   'm' indicates the operand can be in memory.
+   'o' a subset of the 'm' class.  Those memory addressing modes that
+       can be offset at compile time (have a constant added to them).
+
+   Other characters indicate target dependent operand classes and
+   are described in each target's machine description.
+
+   For instructions with more than one operand, sets of classes can be
+   separated by a comma to indicate the appropriate multi-operand constraints.
+   There must be a 1 to 1 correspondence between these sets of classes in
+   all operands for an instruction.
+   */
+DEF_RTL_EXPR(MATCH_OPERAND, "match_operand", "iss", 'm')
+
+/* Appears only in machine descriptions.
+   Means match a SCRATCH or a register.  When used to generate rtl, a
+   SCRATCH is generated.  As for MATCH_OPERAND, the mode specifies
+   the desired mode and the first argument is the operand number.
+   The second argument is the constraint.  */
+DEF_RTL_EXPR(MATCH_SCRATCH, "match_scratch", "is", 'm')
+
+/* Appears only in machine descriptions.
+   Means match only something equal to what is stored in the operand table
+   at the index specified by the argument.  */
+DEF_RTL_EXPR(MATCH_DUP, "match_dup", "i", 'm')
+
+/* Appears only in machine descriptions.
+   Means apply a predicate, AND match recursively the operands of the rtx.
+   Operand 0 is the operand-number, as in match_operand.
+   Operand 1 is a predicate to apply (as a string, a function name).
+   Operand 2 is a vector of expressions, each of which must match
+   one subexpression of the rtx this construct is matching.  */
+DEF_RTL_EXPR(MATCH_OPERATOR, "match_operator", "isE", 'm')
+
+/* Appears only in machine descriptions.
+   Means to match a PARALLEL of arbitrary length.  The predicate is applied
+   to the PARALLEL and the initial expressions in the PARALLEL are matched.
+   Operand 0 is the operand-number, as in match_operand.
+   Operand 1 is a predicate to apply to the PARALLEL.
+   Operand 2 is a vector of expressions, each of which must match the 
+   corresponding element in the PARALLEL.  */
+DEF_RTL_EXPR(MATCH_PARALLEL, "match_parallel", "isE", 'm')
+
+/* Appears only in machine descriptions.
+   Means match only something equal to what is stored in the operand table
+   at the index specified by the argument.  For MATCH_OPERATOR.  */
+DEF_RTL_EXPR(MATCH_OP_DUP, "match_op_dup", "iE", 'm')
+
+/* Appears only in machine descriptions.
+   Defines the pattern for one kind of instruction.
+   Operand:
+   0: names this instruction.
+      If the name is the null string, the instruction is in the
+      machine description just to be recognized, and will never be emitted by
+      the tree to rtl expander.
+   1: is the pattern.
+   2: is a string which is a C expression
+      giving an additional condition for recognizing this pattern.
+      A null string means no extra condition.
+   3: is the action to execute if this pattern is matched.
+      If this assembler code template starts with a * then it is a fragment of
+      C code to run to decide on a template to use.  Otherwise, it is the
+      template to use.
+   4: optionally, a vector of attributes for this insn.
+     */
+DEF_RTL_EXPR(DEFINE_INSN, "define_insn", "sEssV", 'x')
+
+/* Definition of a peephole optimization.
+   1st operand: vector of insn patterns to match
+   2nd operand: C expression that must be true
+   3rd operand: template or C code to produce assembler output.
+   4: optionally, a vector of attributes for this insn.
+     */
+DEF_RTL_EXPR(DEFINE_PEEPHOLE, "define_peephole", "EssV", 'x')
+
+/* Definition of a split operation.
+   1st operand: insn pattern to match
+   2nd operand: C expression that must be true
+   3rd operand: vector of insn patterns to place into a SEQUENCE
+   4th operand: optionally, some C code to execute before generating the
+	insns.  This might, for example, create some RTX's and store them in
+	elements of `recog_operand' for use by the vector of insn-patterns.
+	(`operands' is an alias here for `recog_operand').   */
+DEF_RTL_EXPR(DEFINE_SPLIT, "define_split", "EsES", 'x')
+
+/* Definition of a combiner pattern.
+   Operands not defined yet.  */
+DEF_RTL_EXPR(DEFINE_COMBINE, "define_combine", "Ess", 'x')
+
+/* Define how to generate multiple insns for a standard insn name.
+   1st operand: the insn name.
+   2nd operand: vector of insn-patterns.
+	Use match_operand to substitute an element of `recog_operand'.
+   3rd operand: C expression that must be true for this to be available.
+	This may not test any operands.
+   4th operand: Extra C code to execute before generating the insns.
+	This might, for example, create some RTX's and store them in
+	elements of `recog_operand' for use by the vector of insn-patterns.
+	(`operands' is an alias here for `recog_operand').  */
+DEF_RTL_EXPR(DEFINE_EXPAND, "define_expand", "sEss", 'x')
+   
+/* Define a requirement for delay slots.
+   1st operand: Condition involving insn attributes that, if true,
+	        indicates that the insn requires the number of delay slots
+		shown.
+   2nd operand: Vector whose length is the three times the number of delay
+		slots required.
+	        Each entry gives three conditions, each involving attributes.
+		The first must be true for an insn to occupy that delay slot
+		location.  The second is true for all insns that can be
+		annulled if the branch is true and the third is true for all
+		insns that can be annulled if the branch is false. 
+
+   Multiple DEFINE_DELAYs may be present.  They indicate differing
+   requirements for delay slots.  */
+DEF_RTL_EXPR(DEFINE_DELAY, "define_delay", "eE", 'x')
+
+/* Define a set of insns that requires a function unit.  This means that
+   these insns produce their result after a delay and that there may be
+   restrictions on the number of insns of this type that can be scheduled
+   simultaneously.
+
+   More than one DEFINE_FUNCTION_UNIT can be specified for a function unit.
+   Each gives a set of operations and associated delays.  The first three
+   operands must be the same for each operation for the same function unit.
+
+   All delays are specified in units of COST_PER_CYCLE.
+
+   1st operand: Name of function unit (mostly for documentation)
+   2nd operand: Number of identical function units in CPU
+   3rd operand: Total number of simultaneous insns that can execute on this
+		function unit; 0 if unlimited.
+   4th operand: Condition involving insn attribute, that, if true, specifies
+		those insns that this expression applies to.
+   5th operand: Constant delay after which insn result will be
+		available.
+   6th operand: Delay until next insn can be scheduled on the function unit
+		executing this operation.  The meaning depends on whether or
+		not the next operand is supplied.
+   7th operand: If this operand is not specified, the 6th operand gives the
+		cost of scheduling another operation on this unit while a
+		previous one is active.  A value of zero should be used for a
+		pipelined unit.  If only one operation can be executed a time
+		and the unit is busy for the entire time, the 3rd operand
+		should be specified as 1 and the 6th and 7th operands will
+		be ignored.
+
+		If this operand is specified, it is a list of attribute
+		expressions.  If an insn for which any of these expressions
+		is true is currently executing on the function unit, the
+		delay will be given by the 6th operand.  Otherwise, the
+		insn can be immediately scheduled (subject to the limit on
+		the number of simultaneous operations executing on the
+		unit.)  */
+DEF_RTL_EXPR(DEFINE_FUNCTION_UNIT, "define_function_unit", "siieiiV", 'x')
+
+/* Define attribute computation for `asm' instructions.  */
+DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES, "define_asm_attributes", "V", 'x' )
+
+/* SEQUENCE appears in the result of a `gen_...' function
+   for a DEFINE_EXPAND that wants to make several insns.
+   Its elements are the bodies of the insns that should be made.
+   `emit_insn' takes the SEQUENCE apart and makes separate insns.  */
+DEF_RTL_EXPR(SEQUENCE, "sequence", "E", 'x')
+
+/* Refers to the address of its argument.
+   This appears only in machine descriptions, indicating that
+   any expression that would be acceptable as the operand of MEM
+   should be matched.  */
+DEF_RTL_EXPR(ADDRESS, "address", "e", 'm')
+
+/* ----------------------------------------------------------------------
+   Expressions used for insn attributes.  These also do not appear in
+   actual rtl code in the compiler.
+   ---------------------------------------------------------------------- */
+
+/* Definition of an insn attribute.
+   1st operand: name of the attribute
+   2nd operand: comma-separated list of possible attribute values
+   3rd operand: expression for the default value of the attribute. */
+DEF_RTL_EXPR(DEFINE_ATTR, "define_attr", "sse", 'x')
+
+/* Marker for the name of an attribute. */
+DEF_RTL_EXPR(ATTR, "attr", "s", 'x')
+
+/* For use in the last (optional) operand of DEFINE_INSN or DEFINE_PEEPHOLE and
+   in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that
+   pattern.
+
+   (set_attr "name" "value") is equivalent to
+   (set (attr "name") (const_string "value"))  */
+DEF_RTL_EXPR(SET_ATTR, "set_attr", "ss", 'x')
+
+/* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE, this can be used to
+   specify that attribute values are to be assigned according to the
+   alternative matched.
+
+   The following three expressions are equivalent:
+
+   (set (attr "att") (cond [(eq_attrq "alternative" "1") (const_string "a1")
+			    (eq_attrq "alternative" "2") (const_string "a2")]
+			   (const_string "a3")))
+   (set_attr_alternative "att" [(const_string "a1") (const_string "a2")
+				 (const_string "a3")])
+   (set_attr "att" "a1,a2,a3")
+ */
+DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE, "set_attr_alternative", "sE", 'x')
+
+/* A conditional expression true if the value of the specified attribute of
+   the current insn equals the specified value.  The first operand is the
+   attribute name and the second is the comparison value.  */
+DEF_RTL_EXPR(EQ_ATTR, "eq_attr", "ss", 'x')
+
+/* ----------------------------------------------------------------------
+   Expression types used for things in the instruction chain.
+
+   All formats must start with "iuu" to handle the chain.
+   Each insn expression holds an rtl instruction and its semantics
+   during back-end processing.
+   See macros's in "rtl.h" for the meaning of each rtx->fld[].
+
+   ---------------------------------------------------------------------- */
+
+/* An instruction that cannot jump.  */
+DEF_RTL_EXPR(INSN, "insn", "iuueiee", 'i')
+
+/* An instruction that can possibly jump.
+   Fields ( rtx->fld[] ) have exact same meaning as INSN's.  */
+DEF_RTL_EXPR(JUMP_INSN, "jump_insn", "iuueiee0", 'i')
+
+/* An instruction that can possibly call a subroutine
+   but which will not change which instruction comes next
+   in the current function.
+   Fields ( rtx->fld[] ) have exact same meaning as INSN's.  */
+DEF_RTL_EXPR(CALL_INSN, "call_insn", "iuueiee", 'i')
+
+/* A marker that indicates that control will not flow through.  */
+DEF_RTL_EXPR(BARRIER, "barrier", "iuu", 'x')
+
+/* Holds a label that is followed by instructions.
+   Operand:
+   3: is a number that is unique in the entire compilation.
+   4: is the user-given name of the label, if any.
+   5: is used in jump.c for the use-count of the label.
+   and in flow.c to point to the chain of label_ref's to this label.  */
+DEF_RTL_EXPR(CODE_LABEL, "code_label", "iuuis0", 'x')
+     
+/* Say where in the code a source line starts, for symbol table's sake.
+   Contains a filename and a line number.  Line numbers <= 0 are special:
+   0 is used in a dummy placed at the front of every function
+      just so there will never be a need to delete the first insn;
+   -1 indicates a dummy; insns to be deleted by flow analysis and combining
+      are really changed to NOTEs with a number of -1.
+   -2 means beginning of a name binding contour; output N_LBRAC.
+   -3 means end of a contour; output N_RBRAC.  */
+DEF_RTL_EXPR(NOTE, "note", "iuusn", 'x')
+
+/* INLINE_HEADER is use by inline function machinery.  The information
+   it contains helps to build the mapping function between the rtx's of
+   the function to be inlined and the current function being expanded.  */
+
+DEF_RTL_EXPR(INLINE_HEADER, "inline_header", "iuuuiiiiiieiiEe", 'x')
+
+/* ----------------------------------------------------------------------
+   Top level constituents of INSN, JUMP_INSN and CALL_INSN.
+   ---------------------------------------------------------------------- */
+   
+/* Several operations to be done in parallel.  */
+DEF_RTL_EXPR(PARALLEL, "parallel", "E", 'x')
+
+/* A string that is passed through to the assembler as input.
+     One can obviously pass comments through by using the
+     assembler comment syntax.
+     These occur in an insn all by themselves as the PATTERN.
+     They also appear inside an ASM_OPERANDS
+     as a convenient way to hold a string.  */
+DEF_RTL_EXPR(ASM_INPUT, "asm_input", "s", 'x')
+
+/* An assembler instruction with operands.
+   1st operand is the instruction template.
+   2nd operand is the constraint for the output.
+   3rd operand is the number of the output this expression refers to.
+     When an insn stores more than one value, a separate ASM_OPERANDS
+     is made for each output; this integer distinguishes them.
+   4th is a vector of values of input operands.
+   5th is a vector of modes and constraints for the input operands.
+     Each element is an ASM_INPUT containing a constraint string
+     and whose mode indicates the mode of the input operand.
+   6th is the name of the containing source file.
+   7th is the source line number.  */
+DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEsi", 'x')
+
+/* Vector of addresses, stored as full words.  */
+/* Each element is a LABEL_REF to a CODE_LABEL whose address we want.  */
+DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", 'x')
+
+/* Vector of address differences X0 - BASE, X1 - BASE, ...
+   First operand is BASE; the vector contains the X's.
+   The machine mode of this rtx says how much space to leave
+   for each difference.  */
+DEF_RTL_EXPR(ADDR_DIFF_VEC, "addr_diff_vec", "eE", 'x')
+
+/* ----------------------------------------------------------------------
+   At the top level of an instruction (perhaps under PARALLEL).
+   ---------------------------------------------------------------------- */
+
+/* Assignment.
+   Operand 1 is the location (REG, MEM, PC, CC0 or whatever) assigned to.
+   Operand 2 is the value stored there.
+   ALL assignment must use SET.
+   Instructions that do multiple assignments must use multiple SET,
+   under PARALLEL.  */
+DEF_RTL_EXPR(SET, "set", "ee", 'x')
+
+/* Indicate something is used in a way that we don't want to explain.
+   For example, subroutine calls will use the register
+   in which the static chain is passed.  */
+DEF_RTL_EXPR(USE, "use", "e", 'x')
+
+/* Indicate something is clobbered in a way that we don't want to explain.
+   For example, subroutine calls will clobber some physical registers
+   (the ones that are by convention not saved).  */
+DEF_RTL_EXPR(CLOBBER, "clobber", "e", 'x')
+
+/* Call a subroutine.
+   Operand 1 is the address to call.
+   Operand 2 is the number of arguments.  */
+
+DEF_RTL_EXPR(CALL, "call", "ee", 'x')
+
+/* Return from a subroutine.  */
+
+DEF_RTL_EXPR(RETURN, "return", "", 'x')
+
+/* Conditional trap.
+   Operand 1 is the condition.
+   Operand 2 is the trap code.
+   For an unconditional trap, make the condition (const_int 1).  */
+DEF_RTL_EXPR(TRAP_IF, "trap_if", "ei", 'x')
+
+/* ----------------------------------------------------------------------
+   Primitive values for use in expressions.
+   ---------------------------------------------------------------------- */
+
+/* numeric integer constant */
+DEF_RTL_EXPR(CONST_INT, "const_int", "i", 'o')
+
+/* numeric double constant.
+   Operand 0 is the MEM that stores this constant in memory,
+   or various other things (see comments at immed_double_const in varasm.c).
+   Operand 1 is a chain of all CONST_DOUBLEs in use in the current function.
+   Remaining operands hold the actual value.
+   The number of operands may be more than 2 if cross-compiling;
+   see init_rtl.  */
+DEF_RTL_EXPR(CONST_DOUBLE, "const_double", "e0ii", 'o')
+
+/* String constant.  Used only for attributes right now.  */
+DEF_RTL_EXPR(CONST_STRING, "const_string", "s", 'o')
+
+/* This is used to encapsulate an expression whose value is constant
+   (such as the sum of a SYMBOL_REF and a CONST_INT) so that it will be
+   recognized as a constant operand rather than by arithmetic instructions.  */
+
+DEF_RTL_EXPR(CONST, "const", "e", 'o')
+
+/* program counter.  Ordinary jumps are represented
+   by a SET whose first operand is (PC).  */
+DEF_RTL_EXPR(PC, "pc", "", 'o')
+
+/* A register.  The "operand" is the register number, accessed
+   with the REGNO macro.  If this number is less than FIRST_PSEUDO_REGISTER
+   than a hardware register is being referred to.  */
+DEF_RTL_EXPR(REG, "reg", "i", 'o')
+
+/* A scratch register.  This represents a register used only within a
+   single insn.  It will be turned into a REG during register allocation
+   or reload unless the constraint indicates that the register won't be
+   needed, in which case it can remain a SCRATCH.  This code is
+   marked as having one operand so it can be turned into a REG.  */
+DEF_RTL_EXPR(SCRATCH, "scratch", "0", 'o')
+
+/* One word of a multi-word value.
+   The first operand is the complete value; the second says which word.
+   The WORDS_BIG_ENDIAN flag controls whether word number 0
+   (as numbered in a SUBREG) is the most or least significant word.
+
+   This is also used to refer to a value in a different machine mode.
+   For example, it can be used to refer to a SImode value as if it were
+   Qimode, or vice versa.  Then the word number is always 0.  */
+DEF_RTL_EXPR(SUBREG, "subreg", "ei", 'x')
+
+/* This one-argument rtx is used for move instructions
+   that are guaranteed to alter only the low part of a destination.
+   Thus, (SET (SUBREG:HI (REG...)) (MEM:HI ...))
+   has an unspecified effect on the high part of REG,
+   but (SET (STRICT_LOW_PART (SUBREG:HI (REG...))) (MEM:HI ...))
+   is guaranteed to alter only the bits of REG that are in HImode.
+
+   The actual instruction used is probably the same in both cases,
+   but the register constraints may be tighter when STRICT_LOW_PART
+   is in use.  */
+
+DEF_RTL_EXPR(STRICT_LOW_PART, "strict_low_part", "e", 'x')
+
+/* A memory location; operand is the address.
+   Can be nested inside a VOLATILE.  */
+DEF_RTL_EXPR(MEM, "mem", "e", 'o')
+
+/* Reference to an assembler label in the code for this function.
+   The operand is a CODE_LABEL found in the insn chain.
+   The unprinted fields 1 and 2 are used in flow.c for the
+   LABEL_NEXTREF and CONTAINING_INSN.  */
+DEF_RTL_EXPR(LABEL_REF, "label_ref", "u00", 'o')
+
+/* Reference to a named label: the string that is the first operand,
+   with `_' added implicitly in front.
+   Exception: if the first character explicitly given is `*',
+   to give it to the assembler, remove the `*' and do not add `_'.  */
+DEF_RTL_EXPR(SYMBOL_REF, "symbol_ref", "s", 'o')
+
+/* The condition code register is represented, in our imagination,
+   as a register holding a value that can be compared to zero.
+   In fact, the machine has already compared them and recorded the
+   results; but instructions that look at the condition code
+   pretend to be looking at the entire value and comparing it.  */
+DEF_RTL_EXPR(CC0, "cc0", "", 'o')
+
+/* =====================================================================
+   A QUEUED expression really points to a member of the queue of instructions
+   to be output later for postincrement/postdecrement.
+   QUEUED expressions never become part of instructions.
+   When a QUEUED expression would be put into an instruction,
+   instead either the incremented variable or a copy of its previous
+   value is used.
+   
+   Operands are:
+   0. the variable to be incremented (a REG rtx).
+   1. the incrementing instruction, or 0 if it hasn't been output yet.
+   2. A REG rtx for a copy of the old value of the variable, or 0 if none yet.
+   3. the body to use for the incrementing instruction
+   4. the next QUEUED expression in the queue.
+   ====================================================================== */
+
+DEF_RTL_EXPR(QUEUED, "queued", "eeeee", 'x')
+
+/* ----------------------------------------------------------------------
+   Expressions for operators in an rtl pattern
+   ---------------------------------------------------------------------- */
+
+/* if_then_else.  This is used in representing ordinary
+   conditional jump instructions.
+     Operand:
+     0:  condition
+     1:  then expr
+     2:  else expr */
+DEF_RTL_EXPR(IF_THEN_ELSE, "if_then_else", "eee", '3')
+
+/* General conditional. The first operand is a vector composed of pairs of
+   expressions.  The first element of each pair is evaluated, in turn.
+   The value of the conditional is the second expression of the first pair
+   whose first expression evaluates non-zero.  If none of the expressions is
+   true, the second operand will be used as the value of the conditional.
+
+   This should be replaced with use of IF_THEN_ELSE.  */
+DEF_RTL_EXPR(COND, "cond", "Ee", 'x')
+
+/* Comparison, produces a condition code result.  */
+DEF_RTL_EXPR(COMPARE, "compare", "ee", '2')
+
+/* plus */
+DEF_RTL_EXPR(PLUS, "plus", "ee", 'c')
+
+/* Operand 0 minus operand 1.  */
+DEF_RTL_EXPR(MINUS, "minus", "ee", '2')
+
+/* Minus operand 0.  */
+DEF_RTL_EXPR(NEG, "neg", "e", '1')
+
+DEF_RTL_EXPR(MULT, "mult", "ee", 'c')
+
+/* Operand 0 divided by operand 1.  */
+DEF_RTL_EXPR(DIV, "div", "ee", '2')
+/* Remainder of operand 0 divided by operand 1.  */
+DEF_RTL_EXPR(MOD, "mod", "ee", '2')
+
+/* Unsigned divide and remainder.  */
+DEF_RTL_EXPR(UDIV, "udiv", "ee", '2')
+DEF_RTL_EXPR(UMOD, "umod", "ee", '2')
+
+/* Bitwise operations.  */
+DEF_RTL_EXPR(AND, "and", "ee", 'c')
+
+DEF_RTL_EXPR(IOR, "ior", "ee", 'c')
+
+DEF_RTL_EXPR(XOR, "xor", "ee", 'c')
+
+DEF_RTL_EXPR(NOT, "not", "e", '1')
+
+/* Operand:
+     0:  value to be shifted.
+     1:  number of bits.
+   ASHIFT and LSHIFT are distinguished because on some machines
+   these allow a negative operand and shift right in that case.  */
+DEF_RTL_EXPR(LSHIFT, "lshift", "ee", '2')
+DEF_RTL_EXPR(ASHIFT, "ashift", "ee", '2')
+DEF_RTL_EXPR(ROTATE, "rotate", "ee", '2')
+
+/* Right shift operations, for machines where these are not the same
+   as left shifting with a negative argument.  */
+
+DEF_RTL_EXPR(ASHIFTRT, "ashiftrt", "ee", '2')
+DEF_RTL_EXPR(LSHIFTRT, "lshiftrt", "ee", '2')
+DEF_RTL_EXPR(ROTATERT, "rotatert", "ee", '2')
+
+/* Minimum and maximum values of two operands.  We need both signed and
+   unsigned forms.  (We cannot use MIN for SMIN because it conflicts
+   with a macro of the same name.) */
+
+DEF_RTL_EXPR(SMIN, "smin", "ee", 'c')
+DEF_RTL_EXPR(SMAX, "smax", "ee", 'c')
+DEF_RTL_EXPR(UMIN, "umin", "ee", 'c')
+DEF_RTL_EXPR(UMAX, "umax", "ee", 'c')
+
+/* These unary operations are used to represent incrementation
+   and decrementation as they occur in memory addresses.
+   The amount of increment or decrement are not represented
+   because they can be understood from the machine-mode of the
+   containing MEM.  These operations exist in only two cases:
+   1. pushes onto the stack.
+   2. created automatically by the life_analysis pass in flow.c.  */
+DEF_RTL_EXPR(PRE_DEC, "pre_dec", "e", 'x')
+DEF_RTL_EXPR(PRE_INC, "pre_inc", "e", 'x')
+DEF_RTL_EXPR(POST_DEC, "post_dec", "e", 'x')
+DEF_RTL_EXPR(POST_INC, "post_inc", "e", 'x')
+
+/* Comparison operations.  The ordered comparisons exist in two
+   flavors, signed and unsigned.  */
+DEF_RTL_EXPR(NE, "ne", "ee", '<')
+DEF_RTL_EXPR(EQ, "eq", "ee", '<')
+DEF_RTL_EXPR(GE, "ge", "ee", '<')
+DEF_RTL_EXPR(GT, "gt", "ee", '<')
+DEF_RTL_EXPR(LE, "le", "ee", '<')
+DEF_RTL_EXPR(LT, "lt", "ee", '<')
+DEF_RTL_EXPR(GEU, "geu", "ee", '<')
+DEF_RTL_EXPR(GTU, "gtu", "ee", '<')
+DEF_RTL_EXPR(LEU, "leu", "ee", '<')
+DEF_RTL_EXPR(LTU, "ltu", "ee", '<')
+
+/* Represents the result of sign-extending the sole operand.
+   The machine modes of the operand and of the SIGN_EXTEND expression
+   determine how much sign-extension is going on.  */
+DEF_RTL_EXPR(SIGN_EXTEND, "sign_extend", "e", '1')
+
+/* Similar for zero-extension (such as unsigned short to int).  */
+DEF_RTL_EXPR(ZERO_EXTEND, "zero_extend", "e", '1')
+
+/* Similar but here the operand has a wider mode.  */
+DEF_RTL_EXPR(TRUNCATE, "truncate", "e", '1')
+
+/* Similar for extending floating-point values (such as SFmode to DFmode).  */
+DEF_RTL_EXPR(FLOAT_EXTEND, "float_extend", "e", '1')
+DEF_RTL_EXPR(FLOAT_TRUNCATE, "float_truncate", "e", '1')
+
+/* Conversion of fixed point operand to floating point value.  */
+DEF_RTL_EXPR(FLOAT, "float", "e", '1')
+
+/* With fixed-point machine mode:
+   Conversion of floating point operand to fixed point value.
+   Value is defined only when the operand's value is an integer.
+   With floating-point machine mode (and operand with same mode):
+   Operand is rounded toward zero to produce an integer value
+   represented in floating point.  */
+DEF_RTL_EXPR(FIX, "fix", "e", '1')
+
+/* Conversion of unsigned fixed point operand to floating point value.  */
+DEF_RTL_EXPR(UNSIGNED_FLOAT, "unsigned_float", "e", '1')
+
+/* With fixed-point machine mode:
+   Conversion of floating point operand to *unsigned* fixed point value.
+   Value is defined only when the operand's value is an integer.  */
+DEF_RTL_EXPR(UNSIGNED_FIX, "unsigned_fix", "e", '1')
+
+/* Absolute value */
+DEF_RTL_EXPR(ABS, "abs", "e", '1')
+
+/* Square root */
+DEF_RTL_EXPR(SQRT, "sqrt", "e", '1')
+
+/* Find first bit that is set.
+   Value is 1 + number of trailing zeros in the arg.,
+   or 0 if arg is 0.  */
+DEF_RTL_EXPR(FFS, "ffs", "e", '1')
+
+/* Reference to a signed bit-field of specified size and position.
+   Operand 0 is the memory unit (usually SImode or QImode) which
+   contains the field's first bit.  Operand 1 is the width, in bits.
+   Operand 2 is the number of bits in the memory unit before the
+   first bit of this field.
+   If BITS_BIG_ENDIAN is defined, the first bit is the msb and
+   operand 2 counts from the msb of the memory unit.
+   Otherwise, the first bit is the lsb and operand 2 counts from
+   the lsb of the memory unit.  */
+DEF_RTL_EXPR(SIGN_EXTRACT, "sign_extract", "eee", 'b')
+
+/* Similar for unsigned bit-field.  */
+DEF_RTL_EXPR(ZERO_EXTRACT, "zero_extract", "eee", 'b')
+
+/* For RISC machines.  These save memory when splitting insns.  */
+
+/* HIGH are the high-order bits of a constant expression.  */
+DEF_RTL_EXPR(HIGH, "high", "e", 'o')
+
+/* LO_SUM is the sum of a register and the low-order bits
+   of a constant expression.  */
+DEF_RTL_EXPR(LO_SUM, "lo_sum", "ee", 'o')
+
+/*
+Local variables:
+mode:c
+version-control: t
+End:
+*/