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;; Frv Machine Description;; Copyright (C) 1999, 2000, 2001, 2003, 2004, 2005 Free Software Foundation,;; Inc.;; Contributed by Red Hat, Inc.;; This file is part of GCC.;; GCC 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.;; GCC 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 GCC; see the file COPYING. If not, write to;; the Free Software Foundation, 59 Temple Place - Suite 330,;; Boston, MA 02111-1307, USA.;;- See file "rtl.def" for documentation on define_insn, match_*, et. al.;; ::::::::::::::::::::;; ::;; :: Unspec's used;; ::;; ::::::::::::::::::::;; GOT constants must go 12/HI/LO for the splitter to work(define_constants [(UNSPEC_BLOCKAGE 0) (UNSPEC_CC_TO_GPR 1) (UNSPEC_GPR_TO_CC 2) (UNSPEC_PIC_PROLOGUE 3) (UNSPEC_CR_LOGIC 4) (UNSPEC_STACK_ADJUST 5) (UNSPEC_EH_RETURN_EPILOGUE 6) (UNSPEC_GOT 7) (UNSPEC_LDD 8) (UNSPEC_GETTLSOFF 200) (UNSPEC_TLS_LOAD_GOTTLSOFF12 201) (UNSPEC_TLS_INDIRECT_CALL 202) (UNSPEC_TLS_TLSDESC_LDD 203) (UNSPEC_TLS_TLSDESC_LDD_AUX 204) (UNSPEC_TLS_TLSOFF_LD 205) (UNSPEC_TLS_LDDI 206) (UNSPEC_TLSOFF_HILO 207) (R_FRV_GOT12 11) (R_FRV_GOTHI 12) (R_FRV_GOTLO 13) (R_FRV_FUNCDESC 14) (R_FRV_FUNCDESC_GOT12 15) (R_FRV_FUNCDESC_GOTHI 16) (R_FRV_FUNCDESC_GOTLO 17) (R_FRV_FUNCDESC_VALUE 18) (R_FRV_FUNCDESC_GOTOFF12 19) (R_FRV_FUNCDESC_GOTOFFHI 20) (R_FRV_FUNCDESC_GOTOFFLO 21) (R_FRV_GOTOFF12 22) (R_FRV_GOTOFFHI 23) (R_FRV_GOTOFFLO 24) (R_FRV_GPREL12 25) (R_FRV_GPRELHI 26) (R_FRV_GPRELLO 27) (R_FRV_GOTTLSOFF_HI 28) (R_FRV_GOTTLSOFF_LO 29) (R_FRV_TLSMOFFHI 30) (R_FRV_TLSMOFFLO 31) (R_FRV_TLSMOFF12 32) (R_FRV_TLSDESCHI 33) (R_FRV_TLSDESCLO 34) (R_FRV_GOTTLSDESCHI 35) (R_FRV_GOTTLSDESCLO 36) (GR8_REG 8) (GR9_REG 9) (GR14_REG 14) ;; LR_REG conflicts with definition in frv.h (LRREG 169) (FDPIC_REG 15) ]);; ::::::::::::::::::::;; ::;; :: Constraints;; ::;; ::::::::::::::::::::;; Standard Constraints;;;; `m' A memory operand is allowed, with any kind of address that the;; machine supports in general.;;;; `o' A memory operand is allowed, but only if the address is;; "offsettable". This means that adding a small integer (actually, the;; width in bytes of the operand, as determined by its machine mode) may be;; added to the address and the result is also a valid memory address.;;;; `V' A memory operand that is not offsettable. In other words,;; anything that would fit the `m' constraint but not the `o' constraint.;;;; `<' A memory operand with autodecrement addressing (either;; predecrement or postdecrement) is allowed.;;;; `>' A memory operand with autoincrement addressing (either;; preincrement or postincrement) is allowed.;;;; `r' A register operand is allowed provided that it is in a general;; register.;;;; `d', `a', `f', ...;; Other letters can be defined in machine-dependent fashion to stand for;; particular classes of registers. `d', `a' and `f' are defined on the;; 68000/68020 to stand for data, address and floating point registers.;;;; `i' An immediate integer operand (one with constant value) is allowed.;; This includes symbolic constants whose values will be known only at;; assembly time.;;;; `n' An immediate integer operand with a known numeric value is allowed.;; Many systems cannot support assembly-time constants for operands less;; than a word wide. Constraints for these operands should use `n' rather;; than `i'.;;;; 'I' First machine-dependent integer constant (6 bit signed ints).;; 'J' Second machine-dependent integer constant (10 bit signed ints).;; 'K' Third machine-dependent integer constant (-2048).;; 'L' Fourth machine-dependent integer constant (16 bit signed ints).;; 'M' Fifth machine-dependent integer constant (16 bit unsigned ints).;; 'N' Sixth machine-dependent integer constant (-2047..-1).;; 'O' Seventh machine-dependent integer constant (zero).;; 'P' Eighth machine-dependent integer constant (1..2047).;;;; Other letters in the range `I' through `P' may be defined in a;; machine-dependent fashion to permit immediate integer operands with;; explicit integer values in specified ranges. For example, on the 68000,;; `I' is defined to stand for the range of values 1 to 8. This is the;; range permitted as a shift count in the shift instructions.;;;; `E' An immediate floating operand (expression code `const_double') is;; allowed, but only if the target floating point format is the same as;; that of the host machine (on which the compiler is running).;;;; `F' An immediate floating operand (expression code `const_double') is;; allowed.;;;; 'G' First machine-dependent const_double.;; 'H' Second machine-dependent const_double.;;;; `s' An immediate integer operand whose value is not an explicit;; integer is allowed.;;;; This might appear strange; if an insn allows a constant operand with a;; value not known at compile time, it certainly must allow any known;; value. So why use `s' instead of `i'? Sometimes it allows better code;; to be generated.;;;; For example, on the 68000 in a fullword instruction it is possible to;; use an immediate operand; but if the immediate value is between -128 and;; 127, better code results from loading the value into a register and;; using the register. This is because the load into the register can be;; done with a `moveq' instruction. We arrange for this to happen by;; defining the letter `K' to mean "any integer outside the range -128 to;; 127", and then specifying `Ks' in the operand constraints.;;;; `g' Any register, memory or immediate integer operand is allowed,;; except for registers that are not general registers.;;;; `X' Any operand whatsoever is allowed, even if it does not satisfy;; `general_operand'. This is normally used in the constraint of a;; `match_scratch' when certain alternatives will not actually require a;; scratch register.;;;; `0' Match operand 0.;; `1' Match operand 1.;; `2' Match operand 2.;; `3' Match operand 3.;; `4' Match operand 4.;; `5' Match operand 5.;; `6' Match operand 6.;; `7' Match operand 7.;; `8' Match operand 8.;; `9' Match operand 9.;;;; An operand that matches the specified operand number is allowed. If a;; digit is used together with letters within the same alternative, the;; digit should come last.;;;; This is called a "matching constraint" and what it really means is that;; the assembler has only a single operand that fills two roles considered;; separate in the RTL insn. For example, an add insn has two input;; operands and one output operand in the RTL, but on most CISC machines an;; add instruction really has only two operands, one of them an;; input-output operand:;;;; addl #35,r12;;;; Matching constraints are used in these circumstances. More precisely,;; the two operands that match must include one input-only operand and one;; output-only operand. Moreover, the digit must be a smaller number than;; the number of the operand that uses it in the constraint.;;;; For operands to match in a particular case usually means that they are;; identical-looking RTL expressions. But in a few special cases specific;; kinds of dissimilarity are allowed. For example, `*x' as an input;; operand will match `*x++' as an output operand. For proper results in;; such cases, the output template should always use the output-operand's;; number when printing the operand.;;;; `p' An operand that is a valid memory address is allowed. This is for;; "load address" and "push address" instructions.;;;; `p' in the constraint must be accompanied by `address_operand' as the;; predicate in the `match_operand'. This predicate interprets the mode;; specified in the `match_operand' as the mode of the memory reference for;; which the address would be valid.;;;; `Q` First non constant, non register machine-dependent insns;; `R` Second non constant, non register machine-dependent insns;; `S` Third non constant, non register machine-dependent insns;; `T` Fourth non constant, non register machine-dependent insns;; `U` Fifth non constant, non register machine-dependent insns;;;; Letters in the range `Q' through `U' may be defined in a;; machine-dependent fashion to stand for arbitrary operand types. The;; machine description macro `EXTRA_CONSTRAINT' is passed the operand as;; its first argument and the constraint letter as its second operand.;;;; A typical use for this would be to distinguish certain types of memory;; references that affect other insn operands.;;;; Do not define these constraint letters to accept register references;; (`reg'); the reload pass does not expect this and would not handle it;; properly.;; Multiple Alternative Constraints;; `?' Disparage slightly the alternative that the `?' appears in, as a;; choice when no alternative applies exactly. The compiler regards this;; alternative as one unit more costly for each `?' that appears in it.;;;; `!' Disparage severely the alternative that the `!' appears in. This;; alternative can still be used if it fits without reloading, but if;; reloading is needed, some other alternative will be used.;; Constraint modifiers;; `=' Means that this operand is write-only for this instruction: the;; previous value is discarded and replaced by output data.;;;; `+' Means that this operand is both read and written by the;; instruction.;;;; When the compiler fixes up the operands to satisfy the constraints, it;; needs to know which operands are inputs to the instruction and which are;; outputs from it. `=' identifies an output; `+' identifies an operand;; that is both input and output; all other operands are assumed to be;; input only.;;;; `&' Means (in a particular alternative) that this operand is written;; before the instruction is finished using the input operands. Therefore,;; this operand may not lie in a register that is used as an input operand;; or as part of any memory address.;;;; `&' applies only to the alternative in which it is written. In;; constraints with multiple alternatives, sometimes one alternative;; requires `&' while others do not.;;;; `&' does not obviate the need to write `='.;;;; `%' Declares the instruction to be commutative for this operand and the;; following operand. This means that the compiler may interchange the two;; operands if that is the cheapest way to make all operands fit the;; constraints. This is often used in patterns for addition instructions;; that really have only two operands: the result must go in one of the;; arguments.;;;; `#' Says that all following characters, up to the next comma, are to be;; ignored as a constraint. They are significant only for choosing;; register preferences.;;;; `*' Says that the following character should be ignored when choosing;; register preferences. `*' has no effect on the meaning of the;; constraint as a constraint, and no effect on reloading.;; ::::::::::::::::::::;; ::;; :: Attributes;; ::;; ::::::::::::::::::::;; The `define_attr' expression is used to define each attribute required by;; the target machine. It looks like:;;;; (define_attr NAME LIST-OF-VALUES DEFAULT);; NAME is a string specifying the name of the attribute being defined.;; LIST-OF-VALUES is either a string that specifies a comma-separated list of;; values that can be assigned to the attribute, or a null string to indicate;; that the attribute takes numeric values.;; DEFAULT is an attribute expression that gives the value of this attribute;; for insns that match patterns whose definition does not include an explicit;; value for this attribute.;; For each defined attribute, a number of definitions are written to the;; `insn-attr.h' file. For cases where an explicit set of values is specified;; for an attribute, the following are defined:;; * A `#define' is written for the symbol `HAVE_ATTR_NAME'.;;;; * An enumeral class is defined for `attr_NAME' with elements of the;; form `UPPER-NAME_UPPER-VALUE' where the attribute name and value are first;; converted to upper case.;;;; * A function `get_attr_NAME' is defined that is passed an insn and;; returns the attribute value for that insn.;; For example, if the following is present in the `md' file:;;;; (define_attr "type" "branch,fp,load,store,arith" ...);;;; the following lines will be written to the file `insn-attr.h'.;;;; #define HAVE_ATTR_type;; enum attr_type {TYPE_BRANCH, TYPE_FP, TYPE_LOAD, TYPE_STORE, TYPE_ARITH};;; extern enum attr_type get_attr_type ();;; If the attribute takes numeric values, no `enum' type will be defined and;; the function to obtain the attribute's value will return `int'.(define_attr "length" "" (const_int 4));; Processor type -- this attribute must exactly match the processor_type;; enumeration in frv-protos.h.(define_attr "cpu" "generic,fr550,fr500,fr450,fr405,fr400,fr300,simple,tomcat" (const (symbol_ref "frv_cpu_type")))
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