osprey/cygnus/include/coff/sym.h

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/* Declarations of internal format of MIPS ECOFF symbols.
   Originally contributed by MIPS Computer Systems and Third Eye Software.
   Changes contributed by Cygnus Support are in the public domain.  

   This file is just aggregated with the files that make up the GNU
   release; it is not considered part of GAS, GDB, or other GNU
   programs.  */

/*
 * |-----------------------------------------------------------|
 * | Copyright (c) 1992, 1991, 1990 MIPS Computer Systems, Inc.|
 * | MIPS Computer Systems, Inc. grants reproduction and use   |
 * | rights to all parties, PROVIDED that this comment is      |
 * | maintained in the copy.                                   |
 * |-----------------------------------------------------------|
 */
#ifndef _SYM_H
#define _SYM_H

/* (C) Copyright 1984 by Third Eye Software, Inc.
 *
 * Third Eye Software, Inc. grants reproduction and use rights to
 * all parties, PROVIDED that this comment is maintained in the copy.
 *
 * Third Eye makes no claims about the applicability of this
 * symbol table to a particular use.
 */

/* 
 * This file contains the definition of the Third Eye Symbol Table.
 *
 * Symbols are assumed to be in 'encounter order' - i.e. the order that
 * the things they represent were encountered by the compiler/assembler/loader.
 * EXCEPT for globals!  These are assumed to be bunched together,
 * probably right after the last 'normal' symbol.  Globals ARE sorted
 * in ascending order.
 *
 * -----------------------------------------------------------------------
 * A brief word about Third Eye naming/use conventions:
 *
 * All arrays and index's are 0 based.
 * All "ifooMax" values are the highest legal value PLUS ONE. This makes
 * them good for allocating arrays, etc. All checks are "ifoo < ifooMax".
 *
 * "isym" Index into the SYMbol table.
 * "ipd"  Index into the Procedure Descriptor array.
 * "ifd"  Index into the File Descriptor array.
 * "iss"  Index into String Space.
 * "cb"   Count of Bytes.
 * "rgPd" array whose domain is "0..ipdMax-1" and RanGe is PDR.
 * "rgFd" array whose domain is "0..ifdMax-1" and RanGe is FDR.
 */


/* 
 * Symbolic Header (HDR) structure.
 * As long as all the pointers are set correctly,
 * we don't care WHAT order the various sections come out in!
 *
 * A file produced solely for the use of CDB will probably NOT have
 * any instructions or data areas in it, as these are available
 * in the original.
 */

typedef struct {
  short magic;    /* to verify validity of the table */
  short vstamp;   /* version stamp */
  long  ilineMax; /* number of line number entries */
  bfd_vma cbLine;   /* number of bytes for line number entries */
  bfd_vma cbLineOffset; /* offset to start of line number entries*/
  long  idnMax;   /* max index into dense number table */
  bfd_vma cbDnOffset; /* offset to start dense number table */
  long  ipdMax;   /* number of procedures */
  bfd_vma cbPdOffset; /* offset to procedure descriptor table */
  long  isymMax;  /* number of local symbols */
  bfd_vma cbSymOffset;  /* offset to start of local symbols*/
  long  ioptMax;  /* max index into optimization symbol entries */
  bfd_vma cbOptOffset;  /* offset to optimization symbol entries */
  long  iauxMax;  /* number of auxillary symbol entries */
  bfd_vma cbAuxOffset;  /* offset to start of auxillary symbol entries*/
  long  issMax;   /* max index into local strings */
  bfd_vma cbSsOffset; /* offset to start of local strings */
  long  issExtMax;  /* max index into external strings */
  bfd_vma cbSsExtOffset;  /* offset to start of external strings */
  long  ifdMax;   /* number of file descriptor entries */
  bfd_vma cbFdOffset; /* offset to file descriptor table */
  long  crfd;   /* number of relative file descriptor entries */
  bfd_vma cbRfdOffset;  /* offset to relative file descriptor table */
  long  iextMax;  /* max index into external symbols */
  bfd_vma cbExtOffset;  /* offset to start of external symbol entries*/
  /* If you add machine dependent fields, add them here */
  } HDRR, *pHDRR; 
#define cbHDRR sizeof(HDRR)
#define hdrNil ((pHDRR)0)

/*
 * The FDR and PDR structures speed mapping of address <-> name.
 * They are sorted in ascending memory order and are kept in
 * memory by CDB at runtime.
 */

/* 
 * File Descriptor
 *
 * There is one of these for EVERY FILE, whether compiled with
 * full debugging symbols or not.  The name of a file should be
 * the path name given to the compiler.  This allows the user
 * to simply specify the names of the directories where the COMPILES
 * were done, and we will be able to find their files.
 * A field whose comment starts with "R - " indicates that it will be
 * setup at runtime.
 */
typedef struct fdr {
  bfd_vma adr;    /* memory address of beginning of file */
  long  rss;    /* file name (of source, if known) */
  long  issBase;  /* file's string space */
  bfd_vma cbSs;   /* number of bytes in the ss */
  long  isymBase; /* beginning of symbols */
  long  csym;   /* count file's of symbols */
  long  ilineBase;  /* file's line symbols */
  long  cline;    /* count of file's line symbols */
  long  ioptBase; /* file's optimization entries */
  long  copt;   /* count of file's optimization entries */
  unsigned short ipdFirst;/* start of procedures for this file */
  short cpd;    /* count of procedures for this file */
  long  iauxBase; /* file's auxiliary entries */
  long  caux;   /* count of file's auxiliary entries */
  long  rfdBase;  /* index into the file indirect table */
  long  crfd;   /* count file indirect entries */
  unsigned lang: 5; /* language for this file */
  unsigned fMerge : 1;  /* whether this file can be merged */
  unsigned fReadin : 1; /* true if it was read in (not just created) */
  unsigned fBigendian : 1;/* if set, was compiled on big endian machine */
        /*  aux's will be in compile host's sex */
  unsigned glevel : 2;  /* level this file was compiled with */
  unsigned reserved : 22;  /* reserved for future use */
  bfd_vma cbLineOffset; /* byte offset from header for this file ln's */
  bfd_vma cbLine;   /* size of lines for this file */
  } FDR, *pFDR;
#define cbFDR sizeof(FDR)
#define fdNil ((pFDR)0)
#define ifdNil -1
#define ifdTemp 0
#define ilnNil -1


/* 
 * Procedure Descriptor
 *
 * There is one of these for EVERY TEXT LABEL.
 * If a procedure is in a file with full symbols, then isym
 * will point to the PROC symbols, else it will point to the
 * global symbol for the label.
 */

typedef struct pdr {
  bfd_vma adr;    /* memory address of start of procedure */
  long  isym;   /* start of local symbol entries */
  long  iline;    /* start of line number entries*/
  long  regmask;  /* save register mask */
  long  regoffset;  /* save register offset */
  long  iopt;   /* start of optimization symbol entries*/
  long  fregmask; /* save floating point register mask */
  long  fregoffset; /* save floating point register offset */
  long  frameoffset;  /* frame size */
  short framereg; /* frame pointer register */
  short pcreg;    /* offset or reg of return pc */
  long  lnLow;    /* lowest line in the procedure */
  long  lnHigh;   /* highest line in the procedure */
  bfd_vma cbLineOffset; /* byte offset for this procedure from the fd base */
  /* These fields are new for 64 bit ECOFF.  */
  unsigned gp_prologue : 8; /* byte size of GP prologue */
  unsigned gp_used : 1; /* true if the procedure uses GP */
  unsigned reg_frame : 1; /* true if register frame procedure */
  unsigned prof : 1;  /* true if compiled with -pg */
  unsigned reserved : 13; /* reserved: must be zero */
  unsigned localoff : 8;  /* offset of local variables from vfp */
  } PDR, *pPDR;
#define cbPDR sizeof(PDR)
#define pdNil ((pPDR) 0)
#define ipdNil  -1

/*
 * The structure of the runtime procedure descriptor created by the loader
 * for use by the static exception system.
 */
/*
 * If 0'd out because exception_info chokes Visual C++ and because there
 * don't seem to be any references to this structure elsewhere in gdb.
 */
#if 0
typedef struct runtime_pdr {
  bfd_vma adr;    /* memory address of start of procedure */
  long  regmask;  /* save register mask */
  long  regoffset;  /* save register offset */
  long  fregmask; /* save floating point register mask */
  long  fregoffset; /* save floating point register offset */
  long  frameoffset;  /* frame size */
  short framereg; /* frame pointer register */
  short pcreg;    /* offset or reg of return pc */
  long  irpss;    /* index into the runtime string table */
  long  reserved;
  struct exception_info *exception_info;/* pointer to exception array */
} RPDR, *pRPDR;
#define cbRPDR sizeof(RPDR)
#define rpdNil ((pRPDR) 0)
#endif

/*
 * Line Numbers
 *
 * Line Numbers are segregated from the normal symbols because they
 * are [1] smaller , [2] are of no interest to your
 * average loader, and [3] are never needed in the middle of normal
 * scanning and therefore slow things down.
 *
 * By definition, the first LINER for any given procedure will have
 * the first line of a procedure and represent the first address.
 */

typedef long LINER, *pLINER;
#define lineNil ((pLINER)0)
#define cbLINER sizeof(LINER)
#define ilineNil  -1



/*
 * The Symbol Structure   (GFW, to those who Know!)
 */

typedef struct {
  long  iss;    /* index into String Space of name */
  bfd_vma value;    /* value of symbol */
  unsigned st : 6;  /* symbol type */
  unsigned sc  : 5; /* storage class - text, data, etc */
  unsigned reserved : 1;  /* reserved */
  unsigned index : 20;  /* index into sym/aux table */
  } SYMR, *pSYMR;
#define symNil ((pSYMR)0)
#define cbSYMR sizeof(SYMR)
#define isymNil -1
#define indexNil 0xfffff
#define issNil -1
#define issNull 0


/* The following converts a memory resident string to an iss.
 * This hack is recognized in SbFIss, in sym.c of the debugger.
 */
#define IssFSb(sb) (0x80000000 | ((unsigned long)(sb)))

/* E X T E R N A L   S Y M B O L  R E C O R D
 *
 *  Same as the SYMR except it contains file context to determine where
 *  the index is.
 */
typedef struct ecoff_extr {
  unsigned jmptbl:1;  /* symbol is a jump table entry for shlibs */
  unsigned cobol_main:1;  /* symbol is a cobol main procedure */
  unsigned weakext:1; /* symbol is weak external */
  unsigned reserved:13; /* reserved for future use */
  int ifd;    /* where the iss and index fields point into */
  SYMR  asym;   /* symbol for the external */
  } EXTR, *pEXTR;
#define extNil ((pEXTR)0)
#define cbEXTR sizeof(EXTR)


/* A U X I L L A R Y   T Y P E   I N F O R M A T I O N */

/*
 * Type Information Record
 */
typedef struct {
  unsigned fBitfield : 1; /* set if bit width is specified */
  unsigned continued : 1; /* indicates additional TQ info in next AUX */
  unsigned bt  : 6; /* basic type */
  unsigned tq4 : 4;
  unsigned tq5 : 4;
  /* ---- 16 bit boundary ---- */
  unsigned tq0 : 4;
  unsigned tq1 : 4; /* 6 type qualifiers - tqPtr, etc. */
  unsigned tq2 : 4;
  unsigned tq3 : 4;
  } TIR, *pTIR;
#define cbTIR sizeof(TIR)
#define tiNil ((pTIR)0)
#define itqMax 6

/*
 * Relative symbol record
 *
 * If the rfd field is 4095, the index field indexes into the global symbol
 *  table.
 */

typedef struct {
  unsigned  rfd : 12;    /* index into the file indirect table */
  unsigned  index : 20; /* index int sym/aux/iss tables */
  } RNDXR, *pRNDXR;
#define cbRNDXR sizeof(RNDXR)
#define rndxNil ((pRNDXR)0)

/* dense numbers or sometimes called block numbers are stored in this type,
 *  a rfd of 0xffffffff is an index into the global table.
 */
typedef struct {
  unsigned long rfd;    /* index into the file table */
  unsigned long index;  /* index int sym/aux/iss tables */
  } DNR, *pDNR;
#define cbDNR sizeof(DNR)
#define dnNil ((pDNR)0)



/*
 * Auxillary information occurs only if needed.
 * It ALWAYS occurs in this order when present.

      isymMac   used by stProc only
      TIR     type info
      TIR     additional TQ info (if first TIR was not enough)
      rndx    if (bt == btStruct,btUnion,btEnum,btSet,btRange,
            btTypedef):
            rsym.index == iaux for btSet or btRange
            else rsym.index == isym
      dimLow    btRange, btSet
      dimMac    btRange, btSet
      rndx0   As many as there are tq arrays
      dimLow0
      dimHigh0
      ...
      rndxMax-1
      dimLowMax-1
      dimHighMax-1
      width in bits if (bit field), width in bits.
 */
#define cAuxMax (6 + (idimMax*3))

/* a union of all possible info in the AUX universe */
typedef union {
  TIR ti;   /* type information record */
  RNDXR rndx;   /* relative index into symbol table */
  long  dnLow;    /* low dimension */
  long  dnHigh;   /* high dimension */
  long  isym;   /* symbol table index (end of proc) */
  long  iss;    /* index into string space (not used) */
  long  width;    /* width for non-default sized struc fields */
  long  count;    /* count of ranges for variant arm */
  } AUXU, *pAUXU;
#define cbAUXU sizeof(AUXU)
#define auxNil ((pAUXU)0)
#define iauxNil -1


/*
 * Optimization symbols
 *
 * Optimization symbols contain some overlap information with the normal
 * symbol table. In particular, the proc information
 * is somewhat redundant but necessary to easily find the other information
 * present. 
 *
 * All of the offsets are relative to the beginning of the last otProc
 */

typedef struct {
  unsigned ot: 8;   /* optimization type */
  unsigned value: 24; /* address where we are moving it to */
  RNDXR rndx;   /* points to a symbol or opt entry */
  unsigned long offset; /* relative offset this occured */
  } OPTR, *pOPTR;
#define optNil  ((pOPTR) 0)
#define cbOPTR sizeof(OPTR)
#define ioptNil -1

/*
 * File Indirect
 *
 * When a symbol is referenced across files the following procedure is used:
 *  1) use the file index to get the File indirect entry.
 *  2) use the file indirect entry to get the File descriptor.
 *  3) add the sym index to the base of that file's sym table
 *
 */

typedef long RFDT, *pRFDT;
#define cbRFDT sizeof(RFDT)
#define rfdNil  -1

/*
 * The file indirect table in the mips loader is known as an array of FITs.
 * This is done to keep the code in the loader readable in the area where
 * these tables are merged.  Note this is only a name change.
 */
typedef long FIT, *pFIT;
#define cbFIT sizeof(FIT)
#define ifiNil  -1
#define fiNil ((pFIT) 0)

#ifdef _LANGUAGE_PASCAL
#define ifdNil -1
#define ilnNil -1
#define ipdNil -1
#define ilineNil -1
#define isymNil -1
#define indexNil 16#fffff
#define issNil -1
#define issNull 0
#define itqMax 6
#define iauxNil -1
#define ioptNil -1
#define rfdNil -1
#define ifiNil -1
#endif  /* _LANGUAGE_PASCAL */


/* Dense numbers
 *
 * Rather than use file index, symbol index pairs to represent symbols
 *  and globals, we use dense number so that they can be easily embeded
 *  in intermediate code and the programs that process them can
 *  use direct access tabls instead of hash table (which would be
 *  necesary otherwise because of the sparse name space caused by
 *  file index, symbol index pairs. Dense number are represented
 *  by RNDXRs.
 */

/*
 * The following table defines the meaning of each SYM field as
 * a function of the "st". (scD/B == scData OR scBss)
 *
 * Note: the value "isymMac" is used by symbols that have the concept
 * of enclosing a block of related information.  This value is the
 * isym of the first symbol AFTER the end associated with the primary
 * symbol. For example if a procedure was at isym==90 and had an
 * isymMac==155, the associated end would be at isym==154, and the
 * symbol at 155 would probably (although not necessarily) be the
 * symbol for the next procedure.  This allows rapid skipping over
 * internal information of various sorts. "stEnd"s ALWAYS have the
 * isym of the primary symbol that started the block.
 * 

ST    SC  VALUE   INDEX
--------  ------  --------  ------
stFile    scText  address   isymMac
stLabel   scText  address   ---
stGlobal  scD/B address   iaux
stStatic  scD/B address   iaux
stParam   scAbs offset    iaux
stLocal   scAbs offset    iaux
stProc    scText  address   iaux  (isymMac is first AUX)
stStaticProc  scText  address   iaux  (isymMac is first AUX)

stMember  scNil ordinal   --- (if member of enum)
  (mipsread thinks the case below has a bit, not byte, offset.)
stMember  scNil byte offset iaux  (if member of struct/union)
stMember  scBits  bit offset  iaux  (bit field spec)

stBlock   scText  address   isymMac (text block)
  (the code seems to think that rather than scNil, we see scInfo for
   the two cases below.)
stBlock   scNil cb    isymMac (struct/union member define)
stBlock   scNil cMembers  isymMac (enum member define)

  (New types added by SGI to simplify things:)
stStruct  scInfo  cb    isymMac (struct type define)
stUnion   scInfo  cb    isymMac (union  type define)
stEnum    scInfo  cMembers  isymMac (enum   type define)

stEnd   scText  address   isymStart
stEnd   scNil -------   isymStart (struct/union/enum)

stTypedef scNil -------   iaux
stRegReloc  sc??? value   old register number
stForward sc??? new address isym to original symbol

stConstant  scInfo  value   --- (scalar)
stConstant  scInfo  iss   --- (complex, e.g. string)

 *
 */
#endif

---