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/* ppc-dis.c -- Disassemble PowerPC instructions

   Copyright 1994 Free Software Foundation, Inc.

   Written by Ian Lance Taylor, Cygnus Support

This file is part of GDB, GAS, and the GNU binutils.

GDB, GAS, and the GNU binutils are free software; you can redistribute

them and/or modify them 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.

GDB, GAS, and the GNU binutils are distributed in the hope that they

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 this file; see the file COPYING.  If not, write to the Free

Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#include "dis-asm.h"

/* ppc.h -- Header file for PowerPC opcode table

   Copyright 1994 Free Software Foundation, Inc.

   Written by Ian Lance Taylor, Cygnus Support

This file is part of GDB, GAS, and the GNU binutils.

GDB, GAS, and the GNU binutils are free software; you can redistribute

them and/or modify them under the terms of the GNU General Public

License as published by the Free Software Foundation; either version

1, or (at your option) any later version.

GDB, GAS, and the GNU binutils are distributed in the hope that they

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 this file; see the file COPYING.  If not, write to the Free

Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

/* The opcode table is an array of struct powerpc_opcode.  */

struct powerpc_opcode

{

  /* The opcode name.  */

  const char *name;

  /* The opcode itself.  Those bits which will be filled in with

     operands are zeroes.  */

  uint32_t opcode;

  /* The opcode mask.  This is used by the disassembler.  This is a

     mask containing ones indicating those bits which must match the

     opcode field, and zeroes indicating those bits which need not

     match (and are presumably filled in by operands).  */

  uint32_t mask;

  /* One bit flags for the opcode.  These are used to indicate which

     specific processors support the instructions.  The defined values

     are listed below.  */

  uint32_t flags;

  /* An array of operand codes.  Each code is an index into the

     operand table.  They appear in the order which the operands must

     appear in assembly code, and are terminated by a zero.  */

  unsigned char operands[8];

};

/* The table itself is sorted by major opcode number, and is otherwise

   in the order in which the disassembler should consider

   instructions.  */

extern const struct powerpc_opcode powerpc_opcodes[];

extern const int powerpc_num_opcodes;

/* Values defined for the flags field of a struct powerpc_opcode.  */

/* Opcode is defined for the PowerPC architecture.  */

#define PPC_OPCODE_PPC (01)

/* Opcode is defined for the POWER (RS/6000) architecture.  */

#define PPC_OPCODE_POWER (02)

/* Opcode is defined for the POWER2 (Rios 2) architecture.  */

#define PPC_OPCODE_POWER2 (04)

/* Opcode is only defined on 32 bit architectures.  */

#define PPC_OPCODE_32 (010)

/* Opcode is only defined on 64 bit architectures.  */

#define PPC_OPCODE_64 (020)

/* Opcode is supported by the Motorola PowerPC 601 processor.  The 601

   is assumed to support all PowerPC (PPC_OPCODE_PPC) instructions,

   but it also supports many additional POWER instructions.  */

#define PPC_OPCODE_601 (040)

/* A macro to extract the major opcode from an instruction.  */

#define PPC_OP(i) (((i) >> 26) & 0x3f)

/* The operands table is an array of struct powerpc_operand.  */

struct powerpc_operand

{

  /* The number of bits in the operand.  */

  int bits;

  /* How far the operand is left shifted in the instruction.  */

  int shift;

  /* Insertion function.  This is used by the assembler.  To insert an

     operand value into an instruction, check this field.

     If it is NULL, execute

         i |= (op & ((1 << o->bits) - 1)) << o->shift;

     (i is the instruction which we are filling in, o is a pointer to

     this structure, and op is the opcode value; this assumes twos

     complement arithmetic).

     If this field is not NULL, then simply call it with the

     instruction and the operand value.  It will return the new value

     of the instruction.  If the ERRMSG argument is not NULL, then if

     the operand value is illegal, *ERRMSG will be set to a warning

     string (the operand will be inserted in any case).  If the

     operand value is legal, *ERRMSG will be unchanged (most operands

     can accept any value).  */

  unsigned long (*insert)(uint32_t instruction, int32_t op,

                                   const char **errmsg);

  /* Extraction function.  This is used by the disassembler.  To

     extract this operand type from an instruction, check this field.

     If it is NULL, compute

         op = ((i) >> o->shift) & ((1 << o->bits) - 1);

         if ((o->flags & PPC_OPERAND_SIGNED) != 0

             && (op & (1 << (o->bits - 1))) != 0)

           op -= 1 << o->bits;

     (i is the instruction, o is a pointer to this structure, and op

     is the result; this assumes twos complement arithmetic).

     If this field is not NULL, then simply call it with the

     instruction value.  It will return the value of the operand.  If

     the INVALID argument is not NULL, *INVALID will be set to

     non-zero if this operand type can not actually be extracted from

     this operand (i.e., the instruction does not match).  If the

     operand is valid, *INVALID will not be changed.  */

  long (*extract) (uint32_t instruction, int *invalid);

  /* One bit syntax flags.  */

  uint32_t flags;

};

/* Elements in the table are retrieved by indexing with values from

   the operands field of the powerpc_opcodes table.  */

extern const struct powerpc_operand powerpc_operands[];

/* Values defined for the flags field of a struct powerpc_operand.  */

/* This operand takes signed values.  */

#define PPC_OPERAND_SIGNED (01)

/* This operand takes signed values, but also accepts a full positive

   range of values when running in 32 bit mode.  That is, if bits is

   16, it takes any value from -0x8000 to 0xffff.  In 64 bit mode,

   this flag is ignored.  */

#define PPC_OPERAND_SIGNOPT (02)

/* This operand does not actually exist in the assembler input.  This

   is used to support extended mnemonics such as mr, for which two

   operands fields are identical.  The assembler should call the

   insert function with any op value.  The disassembler should call

   the extract function, ignore the return value, and check the value

   placed in the valid argument.  */

#define PPC_OPERAND_FAKE (04)

/* The next operand should be wrapped in parentheses rather than

   separated from this one by a comma.  This is used for the load and

   store instructions which want their operands to look like

       reg,displacement(reg)

   */

#define PPC_OPERAND_PARENS (010)

/* This operand may use the symbolic names for the CR fields, which

   are

       lt  0        gt  1        eq  2        so  3        un  3

       cr0 0        cr1 1        cr2 2        cr3 3

       cr4 4        cr5 5        cr6 6        cr7 7

   These may be combined arithmetically, as in cr2*4+gt.  These are

   only supported on the PowerPC, not the POWER.  */

#define PPC_OPERAND_CR (020)

/* This operand names a register.  The disassembler uses this to print

   register names with a leading 'r'.  */

#define PPC_OPERAND_GPR (040)

/* This operand names a floating point register.  The disassembler

   prints these with a leading 'f'.  */

#define PPC_OPERAND_FPR (0100)

/* This operand is a relative branch displacement.  The disassembler

   prints these symbolically if possible.  */

#define PPC_OPERAND_RELATIVE (0200)

/* This operand is an absolute branch address.  The disassembler

   prints these symbolically if possible.  */

#define PPC_OPERAND_ABSOLUTE (0400)

/* This operand is optional, and is zero if omitted.  This is used for

   the optional BF and L fields in the comparison instructions.  The

   assembler must count the number of operands remaining on the line,

   and the number of operands remaining for the opcode, and decide

   whether this operand is present or not.  The disassembler should

   print this operand out only if it is not zero.  */

#define PPC_OPERAND_OPTIONAL (01000)

/* This flag is only used with PPC_OPERAND_OPTIONAL.  If this operand

   is omitted, then for the next operand use this operand value plus

   1, ignoring the next operand field for the opcode.  This wretched

   hack is needed because the Power rotate instructions can take

   either 4 or 5 operands.  The disassembler should print this operand

   out regardless of the PPC_OPERAND_OPTIONAL field.  */

#define PPC_OPERAND_NEXT (02000)

/* This operand should be regarded as a negative number for the

   purposes of overflow checking (i.e., the normal most negative

   number is disallowed and one more than the normal most positive

   number is allowed).  This flag will only be set for a signed

   operand.  */

#define PPC_OPERAND_NEGATIVE (04000)

/* The POWER and PowerPC assemblers use a few macros.  We keep them

   with the operands table for simplicity.  The macro table is an

   array of struct powerpc_macro.  */

struct powerpc_macro

{

  /* The macro name.  */

  const char *name;

  /* The number of operands the macro takes.  */

  unsigned int operands;

  /* One bit flags for the opcode.  These are used to indicate which

     specific processors support the instructions.  The values are the

     same as those for the struct powerpc_opcode flags field.  */

  uint32_t flags;

  /* A format string to turn the macro into a normal instruction.

     Each %N in the string is replaced with operand number N (zero

     based).  */

  const char *format;

};

extern const struct powerpc_macro powerpc_macros[];

extern const int powerpc_num_macros;

/* ppc-opc.c -- PowerPC opcode list

   Copyright 1994 Free Software Foundation, Inc.

   Written by Ian Lance Taylor, Cygnus Support

This file is part of GDB, GAS, and the GNU binutils.

GDB, GAS, and the GNU binutils are free software; you can redistribute

them and/or modify them 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.

GDB, GAS, and the GNU binutils are distributed in the hope that they

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 this file; see the file COPYING.  If not, write to the Free

Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

/* This file holds the PowerPC opcode table.  The opcode table

   includes almost all of the extended instruction mnemonics.  This

   permits the disassembler to use them, and simplifies the assembler

   logic, at the cost of increasing the table size.  The table is

   strictly constant data, so the compiler should be able to put it in

   the .text section.

   This file also holds the operand table.  All knowledge about

   inserting operands into instructions and vice-versa is kept in this

   file.  */

/* Local insertion and extraction functions.  */

static unsigned long insert_bat (uint32_t, int32_t, const char **);

static long extract_bat(uint32_t, int *);

static unsigned long insert_bba(uint32_t, int32_t, const char **);

static long extract_bba(uint32_t, int *);

static unsigned long insert_bd(uint32_t, int32_t, const char **);

static long extract_bd(uint32_t, int *);

static unsigned long insert_bdm(uint32_t, int32_t, const char **);

static long extract_bdm(uint32_t, int *);

static unsigned long insert_bdp(uint32_t, int32_t, const char **);

static long extract_bdp(uint32_t, int *);

static unsigned long insert_bo(uint32_t, int32_t, const char **);

static long extract_bo(uint32_t, int *);

static unsigned long insert_boe(uint32_t, int32_t, const char **);

static long extract_boe(uint32_t, int *);

static unsigned long insert_ds(uint32_t, int32_t, const char **);

static long extract_ds(uint32_t, int *);

static unsigned long insert_li(uint32_t, int32_t, const char **);

static long extract_li(uint32_t, int *);

static unsigned long insert_mbe(uint32_t, int32_t, const char **);

static long extract_mbe(uint32_t, int *);

static unsigned long insert_mb6(uint32_t, int32_t, const char **);

static long extract_mb6(uint32_t, int *);

static unsigned long insert_nb(uint32_t, int32_t, const char **);

static long extract_nb(uint32_t, int *);

static unsigned long insert_nsi(uint32_t, int32_t, const char **);

static long extract_nsi(uint32_t, int *);

static unsigned long insert_ral(uint32_t, int32_t, const char **);

static unsigned long insert_ram(uint32_t, int32_t, const char **);

static unsigned long insert_ras(uint32_t, int32_t, const char **);

static unsigned long insert_rbs(uint32_t, int32_t, const char **);

static long extract_rbs(uint32_t, int *);

static unsigned long insert_sh6(uint32_t, int32_t, const char **);

static long extract_sh6(uint32_t, int *);

static unsigned long insert_spr(uint32_t, int32_t, const char **);

static long extract_spr(uint32_t, int *);

static unsigned long insert_tbr(uint32_t, int32_t, const char **);

static long extract_tbr(uint32_t, int *);

/* The operands table.

   The fields are bits, shift, signed, insert, extract, flags.  */

const struct powerpc_operand powerpc_operands[] =

{

  /* The zero index is used to indicate the end of the list of

     operands.  */

#define UNUSED (0)

  { 0, 0, 0, 0, 0 },

  /* The BA field in an XL form instruction.  */

#define BA (1)

#define BA_MASK (0x1f << 16)

  { 5, 16, 0, 0, PPC_OPERAND_CR },

  /* The BA field in an XL form instruction when it must be the same

     as the BT field in the same instruction.  */

#define BAT (2)

  { 5, 16, insert_bat, extract_bat, PPC_OPERAND_FAKE },

  /* The BB field in an XL form instruction.  */

#define BB (3)

#define BB_MASK (0x1f << 11)

  { 5, 11, 0, 0, PPC_OPERAND_CR },

  /* The BB field in an XL form instruction when it must be the same

     as the BA field in the same instruction.  */

#define BBA (4)

  { 5, 11, insert_bba, extract_bba, PPC_OPERAND_FAKE },

  /* The BD field in a B form instruction.  The lower two bits are

     forced to zero.  */

#define BD (5)

  { 16, 0, insert_bd, extract_bd, PPC_OPERAND_RELATIVE | PPC_OPERAND_SIGNED },

  /* The BD field in a B form instruction when absolute addressing is

     used.  */

#define BDA (6)

  { 16, 0, insert_bd, extract_bd, PPC_OPERAND_ABSOLUTE | PPC_OPERAND_SIGNED },

  /* The BD field in a B form instruction when the - modifier is used.

     This sets the y bit of the BO field appropriately.  */

#define BDM (7)

  { 16, 0, insert_bdm, extract_bdm,

      PPC_OPERAND_RELATIVE | PPC_OPERAND_SIGNED },

  /* The BD field in a B form instruction when the - modifier is used

     and absolute address is used.  */

#define BDMA (8)

  { 16, 0, insert_bdm, extract_bdm,

      PPC_OPERAND_ABSOLUTE | PPC_OPERAND_SIGNED },

  /* The BD field in a B form instruction when the + modifier is used.

     This sets the y bit of the BO field appropriately.  */

#define BDP (9)

  { 16, 0, insert_bdp, extract_bdp,

      PPC_OPERAND_RELATIVE | PPC_OPERAND_SIGNED },

  /* The BD field in a B form instruction when the + modifier is used

     and absolute addressing is used.  */

#define BDPA (10)

  { 16, 0, insert_bdp, extract_bdp,

      PPC_OPERAND_ABSOLUTE | PPC_OPERAND_SIGNED },

  /* The BF field in an X or XL form instruction.  */

#define BF (11)

  { 3, 23, 0, 0, PPC_OPERAND_CR },

  /* An optional BF field.  This is used for comparison instructions,

     in which an omitted BF field is taken as zero.  */

#define OBF (12)

  { 3, 23, 0, 0, PPC_OPERAND_CR | PPC_OPERAND_OPTIONAL },

  /* The BFA field in an X or XL form instruction.  */

#define BFA (13)

  { 3, 18, 0, 0, PPC_OPERAND_CR },

  /* The BI field in a B form or XL form instruction.  */

#define BI (14)

#define BI_MASK (0x1f << 16)

  { 5, 16, 0, 0, PPC_OPERAND_CR },

  /* The BO field in a B form instruction.  Certain values are

     illegal.  */

#define BO (15)

#define BO_MASK (0x1f << 21)

  { 5, 21, insert_bo, extract_bo, 0 },

  /* The BO field in a B form instruction when the + or - modifier is

     used.  This is like the BO field, but it must be even.  */

#define BOE (16)

  { 5, 21, insert_boe, extract_boe, 0 },

  /* The BT field in an X or XL form instruction.  */

#define BT (17)

  { 5, 21, 0, 0, PPC_OPERAND_CR },

  /* The condition register number portion of the BI field in a B form

     or XL form instruction.  This is used for the extended

     conditional branch mnemonics, which set the lower two bits of the

     BI field.  This field is optional.  */

#define CR (18)

  { 3, 18, 0, 0, PPC_OPERAND_CR | PPC_OPERAND_OPTIONAL },

  /* The D field in a D form instruction.  This is a displacement off

     a register, and implies that the next operand is a register in

     parentheses.  */

#define D (19)

  { 16, 0, 0, 0, PPC_OPERAND_PARENS | PPC_OPERAND_SIGNED },

  /* The DS field in a DS form instruction.  This is like D, but the

     lower two bits are forced to zero.  */

#define DS (20)

  { 16, 0, insert_ds, extract_ds, PPC_OPERAND_PARENS | PPC_OPERAND_SIGNED },

  /* The FL1 field in a POWER SC form instruction.  */

#define FL1 (21)

  { 4, 12, 0, 0, 0 },

  /* The FL2 field in a POWER SC form instruction.  */

#define FL2 (22)

  { 3, 2, 0, 0, 0 },

  /* The FLM field in an XFL form instruction.  */

#define FLM (23)

  { 8, 17, 0, 0, 0 },

  /* The FRA field in an X or A form instruction.  */

#define FRA (24)

#define FRA_MASK (0x1f << 16)

  { 5, 16, 0, 0, PPC_OPERAND_FPR },

  /* The FRB field in an X or A form instruction.  */

#define FRB (25)

#define FRB_MASK (0x1f << 11)

  { 5, 11, 0, 0, PPC_OPERAND_FPR },

  /* The FRC field in an A form instruction.  */

#define FRC (26)

#define FRC_MASK (0x1f << 6)

  { 5, 6, 0, 0, PPC_OPERAND_FPR },

  /* The FRS field in an X form instruction or the FRT field in a D, X

     or A form instruction.  */

#define FRS (27)

#define FRT (FRS)

  { 5, 21, 0, 0, PPC_OPERAND_FPR },

  /* The FXM field in an XFX instruction.  */

#define FXM (28)

#define FXM_MASK (0xff << 12)

  { 8, 12, 0, 0, 0 },

  /* The L field in a D or X form instruction.  */

#define L (29)

  { 1, 21, 0, 0, PPC_OPERAND_OPTIONAL },

  /* The LEV field in a POWER SC form instruction.  */

#define LEV (30)

  { 7, 5, 0, 0, 0 },

  /* The LI field in an I form instruction.  The lower two bits are

     forced to zero.  */

#define LI (31)

  { 26, 0, insert_li, extract_li, PPC_OPERAND_RELATIVE | PPC_OPERAND_SIGNED },

  /* The LI field in an I form instruction when used as an absolute

     address.  */

#define LIA (32)

  { 26, 0, insert_li, extract_li, PPC_OPERAND_ABSOLUTE | PPC_OPERAND_SIGNED },

  /* The MB field in an M form instruction.  */

#define MB (33)

#define MB_MASK (0x1f << 6)

  { 5, 6, 0, 0, 0 },

  /* The ME field in an M form instruction.  */

#define ME (34)

#define ME_MASK (0x1f << 1)

  { 5, 1, 0, 0, 0 },

  /* The MB and ME fields in an M form instruction expressed a single

     operand which is a bitmask indicating which bits to select.  This

     is a two operand form using PPC_OPERAND_NEXT.  See the

     description in opcode/ppc.h for what this means.  */

#define MBE (35)

  { 5, 6, 0, 0, PPC_OPERAND_OPTIONAL | PPC_OPERAND_NEXT },

  { 32, 0, insert_mbe, extract_mbe, 0 },

  /* The MB or ME field in an MD or MDS form instruction.  The high

     bit is wrapped to the low end.  */

#define MB6 (37)

#define ME6 (MB6)

#define MB6_MASK (0x3f << 5)

  { 6, 5, insert_mb6, extract_mb6, 0 },

  /* The NB field in an X form instruction.  The value 32 is stored as

     0.  */

#define NB (38)

  { 6, 11, insert_nb, extract_nb, 0 },

  /* The NSI field in a D form instruction.  This is the same as the

     SI field, only negated.  */

#define NSI (39)

  { 16, 0, insert_nsi, extract_nsi,

      PPC_OPERAND_NEGATIVE | PPC_OPERAND_SIGNED },

  /* The RA field in an D, DS, X, XO, M, or MDS form instruction.  */

#define RA (40)

#define RA_MASK (0x1f << 16)

  { 5, 16, 0, 0, PPC_OPERAND_GPR },

  /* The RA field in a D or X form instruction which is an updating

     load, which means that the RA field may not be zero and may not

     equal the RT field.  */

#define RAL (41)

  { 5, 16, insert_ral, 0, PPC_OPERAND_GPR },

  /* The RA field in an lmw instruction, which has special value

     restrictions.  */

#define RAM (42)

  { 5, 16, insert_ram, 0, PPC_OPERAND_GPR },

  /* The RA field in a D or X form instruction which is an updating

     store or an updating floating point load, which means that the RA

     field may not be zero.  */

#define RAS (43)

  { 5, 16, insert_ras, 0, PPC_OPERAND_GPR },

  /* The RB field in an X, XO, M, or MDS form instruction.  */

#define RB (44)

#define RB_MASK (0x1f << 11)

  { 5, 11, 0, 0, PPC_OPERAND_GPR },

  /* The RB field in an X form instruction when it must be the same as

     the RS field in the instruction.  This is used for extended

     mnemonics like mr.  */

#define RBS (45)

  { 5, 1, insert_rbs, extract_rbs, PPC_OPERAND_FAKE },

  /* The RS field in a D, DS, X, XFX, XS, M, MD or MDS form

     instruction or the RT field in a D, DS, X, XFX or XO form

     instruction.  */

#define RS (46)

#define RT (RS)

#define RT_MASK (0x1f << 21)

  { 5, 21, 0, 0, PPC_OPERAND_GPR },

  /* The SH field in an X or M form instruction.  */

#define SH (47)

#define SH_MASK (0x1f << 11)

  { 5, 11, 0, 0, 0 },

  /* The SH field in an MD form instruction.  This is split.  */

#define SH6 (48)

#define SH6_MASK ((0x1f << 11) | (1 << 1))

  { 6, 1, insert_sh6, extract_sh6, 0 },

  /* The SI field in a D form instruction.  */

#define SI (49)

  { 16, 0, 0, 0, PPC_OPERAND_SIGNED },

  /* The SI field in a D form instruction when we accept a wide range

     of positive values.  */

#define SISIGNOPT (50)

  { 16, 0, 0, 0, PPC_OPERAND_SIGNED | PPC_OPERAND_SIGNOPT },

  /* The SPR field in an XFX form instruction.  This is flipped--the

     lower 5 bits are stored in the upper 5 and vice- versa.  */

#define SPR (51)

#define SPR_MASK (0x3ff << 11)

  { 10, 11, insert_spr, extract_spr, 0 },

  /* The BAT index number in an XFX form m[ft]ibat[lu] instruction.  */

#define SPRBAT (52)

#define SPRBAT_MASK (0x3 << 17)

  { 2, 17, 0, 0, 0 },

  /* The SPRG register number in an XFX form m[ft]sprg instruction.  */

#define SPRG (53)

#define SPRG_MASK (0x3 << 16)

  { 2, 16, 0, 0, 0 },

  /* The SR field in an X form instruction.  */

#define SR (54)

  { 4, 16, 0, 0, 0 },

  /* The SV field in a POWER SC form instruction.  */

#define SV (55)

  { 14, 2, 0, 0, 0 },

  /* The TBR field in an XFX form instruction.  This is like the SPR

     field, but it is optional.  */

#define TBR (56)

  { 10, 11, insert_tbr, extract_tbr, PPC_OPERAND_OPTIONAL },

  /* The TO field in a D or X form instruction.  */

#define TO (57)

#define TO_MASK (0x1f << 21)

  { 5, 21, 0, 0, 0 },

  /* The U field in an X form instruction.  */

#define U (58)

  { 4, 12, 0, 0, 0 },

  /* The UI field in a D form instruction.  */

#define UI (59)

  { 16, 0, 0, 0, 0 },

};

/* The functions used to insert and extract complicated operands.  */

/* The BA field in an XL form instruction when it must be the same as

   the BT field in the same instruction.  This operand is marked FAKE.

   The insertion function just copies the BT field into the BA field,

   and the extraction function just checks that the fields are the

   same.  */

/*ARGSUSED*/

static unsigned long

insert_bat (insn, value, errmsg)

     uint32_t insn;

     int32_t value;

     const char **errmsg;

{

  return insn | (((insn >> 21) & 0x1f) << 16);

}

static long

extract_bat (insn, invalid)

     uint32_t insn;

     int *invalid;

{

  if (invalid != (int *) NULL

      && ((insn >> 21) & 0x1f) != ((insn >> 16) & 0x1f))

    *invalid = 1;

  return 0;

}

/* The BB field in an XL form instruction when it must be the same as

   the BA field in the same instruction.  This operand is marked FAKE.

   The insertion function just copies the BA field into the BB field,

   and the extraction function just checks that the fields are the

   same.  */

/*ARGSUSED*/

static unsigned long

insert_bba (insn, value, errmsg)

     uint32_t insn;

     int32_t value;

     const char **errmsg;

{

  return insn | (((insn >> 16) & 0x1f) << 11);

}

static long

extract_bba (insn, invalid)

     uint32_t insn;

     int *invalid;

{

  if (invalid != (int *) NULL

      && ((insn >> 16) & 0x1f) != ((insn >> 11) & 0x1f))

    *invalid = 1;

  return 0;

}

/* The BD field in a B form instruction.  The lower two bits are

   forced to zero.  */

/*ARGSUSED*/

static unsigned long

insert_bd (insn, value, errmsg)

     uint32_t insn;

     int32_t value;

     const char **errmsg;

{

  return insn | (value & 0xfffc);

}

/*ARGSUSED*/

static long

extract_bd (insn, invalid)

     uint32_t insn;

     int *invalid;

{

  if ((insn & 0x8000) != 0)

    return (insn & 0xfffc) - 0x10000;

  else

    return insn & 0xfffc;

}

/* The BD field in a B form instruction when the - modifier is used.

   This modifier means that the branch is not expected to be taken.

   We must set the y bit of the BO field to 1 if the offset is

   negative.  When extracting, we require that the y bit be 1 and that

   the offset be positive, since if the y bit is 0 we just want to

   print the normal form of the instruction.  */

/*ARGSUSED*/

static unsigned long

insert_bdm (insn, value, errmsg)

     uint32_t insn;

     int32_t value;

     const char **errmsg;

{

  if ((value & 0x8000) != 0)

    insn |= 1 << 21;

  return insn | (value & 0xfffc);

}

static long

extract_bdm (insn, invalid)

     uint32_t insn;

     int *invalid;

{

  if (invalid != (int *) NULL

      && ((insn & (1 << 21)) == 0

          || (insn & (1 << 15)) == 0))

    *invalid = 1;

  if ((insn & 0x8000) != 0)

    return (insn & 0xfffc) - 0x10000;

  else

    return insn & 0xfffc;

}

/* The BD field in a B form instruction when the + modifier is used.

   This is like BDM, above, except that the branch is expected to be

   taken.  */

/*ARGSUSED*/

static unsigned long

insert_bdp (insn, value, errmsg)

     uint32_t insn;

     int32_t value;

     const char **errmsg;

{

  if ((value & 0x8000) == 0)

    insn |= 1 << 21;

  return insn | (value & 0xfffc);

}

static long

extract_bdp (insn, invalid)

     uint32_t insn;

     int *invalid;

{

  if (invalid != (int *) NULL

      && ((insn & (1 << 21)) == 0

          || (insn & (1 << 15)) != 0))

    *invalid = 1;

  if ((insn & 0x8000) != 0)

    return (insn & 0xfffc) - 0x10000;

  else

    return insn & 0xfffc;

}

/* Check for legal values of a BO field.  */

static int

valid_bo (int32_t value)

{

  /* Certain encodings have bits that are required to be zero.  These

     are (z must be zero, y may be anything):

         001zy

         011zy

         1z00y

         1z01y

         1z1zz

     */

  switch (value & 0x14)

    {

    default:

    case 0:

      return 1;

    case 0x4:

      return (value & 0x2) == 0;

    case 0x10:

      return (value & 0x8) == 0;

    case 0x14:

      return value == 0x14;

    }

}

/* The BO field in a B form instruction.  Warn about attempts to set

   the field to an illegal value.  */

static unsigned long

insert_bo (insn, value, errmsg)

     uint32_t insn;

     int32_t value;

     const char **errmsg;

{

  if (errmsg != (const char **) NULL

      && ! valid_bo (value))

    *errmsg = "invalid conditional option";

  return insn | ((value & 0x1f) << 21);

}

static long

extract_bo (insn, invalid)

     uint32_t insn;

     int *invalid;

{

  int32_t value;

  value = (insn >> 21) & 0x1f;

  if (invalid != (int *) NULL

      && ! valid_bo (value))

    *invalid = 1;

  return value;

}

/* The BO field in a B form instruction when the + or - modifier is

   used.  This is like the BO field, but it must be even.  When

   extracting it, we force it to be even.  */

static unsigned long

insert_boe (insn, value, errmsg)