Modified Files:

[binutils.git] / gdb / minsyms.c

diff --git a/gdb/minsyms.c b/gdb/minsyms.c
index 164159241b46627a1cbffc8c3efd5fd2aba58428..fde97e9e6cfb12cbe481374f68292cf435e0641c 100644 (file)
--- a/gdb/minsyms.c
+++ b/gdb/minsyms.c
@@ -1,5 +1,5 @@
 /* GDB routines for manipulating the minimal symbol tables.
 /* GDB routines for manipulating the minimal symbol tables.

-   Copyright 1992 Free Software Foundation, Inc.
+   Copyright 1992, 1993, 1994 Free Software Foundation, Inc.

    Contributed by Cygnus Support, using pieces from other GDB modules.
 
 This file is part of GDB.
    Contributed by Cygnus Support, using pieces from other GDB modules.
 
 This file is part of GDB.


@@ -38,10 +38,13 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
 
 
 #include "defs.h"
 
 
 #include "defs.h"

+#include <string.h>

 #include "symtab.h"
 #include "bfd.h"
 #include "symfile.h"
 #include "objfiles.h"
 #include "symtab.h"
 #include "bfd.h"
 #include "symfile.h"
 #include "objfiles.h"

+#include "demangle.h"
+#include "gdb-stabs.h"

 
 /* Accumulate the minimal symbols for each objfile in bunches of BUNCH_SIZE.
    At the end, copy them all into one newly allocated location on an objfile's
 
 /* Accumulate the minimal symbols for each objfile in bunches of BUNCH_SIZE.
    At the end, copy them all into one newly allocated location on an objfile's


@@ -94,9 +97,8 @@ lookup_minimal_symbol (name, objf)
   struct objfile *objfile;
   struct minimal_symbol *msymbol;
   struct minimal_symbol *found_symbol = NULL;
   struct objfile *objfile;
   struct minimal_symbol *msymbol;
   struct minimal_symbol *found_symbol = NULL;

-#ifdef IBM6000_TARGET
+  struct minimal_symbol *found_file_symbol = NULL;

   struct minimal_symbol *trampoline_symbol = NULL;
   struct minimal_symbol *trampoline_symbol = NULL;

-#endif

 
   for (objfile = object_files;
        objfile != NULL && found_symbol == NULL;
 
   for (objfile = object_files;
        objfile != NULL && found_symbol == NULL;


@@ -105,43 +107,55 @@ lookup_minimal_symbol (name, objf)
       if (objf == NULL || objf == objfile)
        {
          for (msymbol = objfile -> msymbols;
       if (objf == NULL || objf == objfile)
        {
          for (msymbol = objfile -> msymbols;

-              msymbol != NULL && msymbol -> name != NULL &&
+              msymbol != NULL && SYMBOL_NAME (msymbol) != NULL &&

               found_symbol == NULL;
               msymbol++)
            {
               found_symbol == NULL;
               msymbol++)
            {

-             if (strcmp (msymbol -> name, name) == 0)
+             if (SYMBOL_MATCHES_NAME (msymbol, name))

                {
                {

-#ifdef IBM6000_TARGET
-/* I *think* all platforms using shared libraries (and trampoline code)
- * will suffer this problem. Consider a case where there are 5 shared
- * libraries, each referencing `foo' with a trampoline entry. When someone
- * wants to put a breakpoint on `foo' and the only info we have is minimal
- * symbol vector, we want to use the real `foo', rather than one of those
- * trampoline entries. MGO */  
-         /* If a trampoline symbol is found, we prefer to keep looking
-            for the *real* symbol. If the actual symbol not found,
-            then we'll use the trampoline entry. Sorry for the machine
-            dependent code here, but I hope this will benefit other
-            platforms as well. For trampoline entries, we used mst_unknown
-            earlier. Perhaps we should define a `mst_trampoline' type?? */
-
-                 if (msymbol->type != mst_unknown)
-                   found_symbol = msymbol;
-                 else if (msymbol->type == mst_unknown && !trampoline_symbol)
-                   trampoline_symbol = msymbol;
-                    
-#else
-                 found_symbol = msymbol;
-#endif
+                 switch (MSYMBOL_TYPE (msymbol))
+                   {
+                   case mst_file_text:
+                   case mst_file_data:
+                   case mst_file_bss:
+                     /* It is file-local.  If we find more than one, just
+                        return the latest one (the user can't expect
+                        useful behavior in that case).  */
+                     found_file_symbol = msymbol;
+                     break;
+
+                   case mst_solib_trampoline:
+
+                     /* If a trampoline symbol is found, we prefer to
+                        keep looking for the *real* symbol. If the
+                        actual symbol is not found, then we'll use the
+                        trampoline entry. */
+                     if (trampoline_symbol == NULL)
+                       trampoline_symbol = msymbol;
+                     break;
+
+                   case mst_unknown:
+                   default:
+                     found_symbol = msymbol;
+                     break;
+                   }

                }
            }
        }
     }
                }
            }
        }
     }

-#ifdef IBM6000_TARGET
-  return found_symbol ? found_symbol : trampoline_symbol;
-#endif
+  /* External symbols are best.  */
+  if (found_symbol)
+    return found_symbol;
+
+  /* File-local symbols are next best.  */
+  if (found_file_symbol)
+    return found_file_symbol;

 
 

-  return (found_symbol);
+  /* Symbols for shared library trampolines are next best.  */
+  if (trampoline_symbol)
+    return trampoline_symbol;
+
+  return NULL;

 }
 
 
 }
 
 


@@ -150,7 +164,9 @@ lookup_minimal_symbol (name, objf)
    equal to PC.  Returns a pointer to the minimal symbol if such a symbol
    is found, or NULL if PC is not in a suitable range.  Note that we need
    to look through ALL the minimal symbol tables before deciding on the
    equal to PC.  Returns a pointer to the minimal symbol if such a symbol
    is found, or NULL if PC is not in a suitable range.  Note that we need
    to look through ALL the minimal symbol tables before deciding on the

-   symbol that comes closest to the specified PC. */
+   symbol that comes closest to the specified PC.  This is because objfiles
+   can overlap, for example objfile A has .text at 0x100 and .data at 0x40000
+   and objfile B has .text at 0x234 and .data at 0x40048.  */

 
 struct minimal_symbol *
 lookup_minimal_symbol_by_pc (pc)
 
 struct minimal_symbol *
 lookup_minimal_symbol_by_pc (pc)


@@ -176,8 +192,8 @@ lookup_minimal_symbol_by_pc (pc)
       if ((msymbol = objfile -> msymbols) != NULL)
        {
          lo = 0;
       if ((msymbol = objfile -> msymbols) != NULL)
        {
          lo = 0;

-         hi = objfile -> minimal_symbol_count - 2;
-         
+         hi = objfile -> minimal_symbol_count - 1;
+

          /* This code assumes that the minimal symbols are sorted by
             ascending address values.  If the pc value is greater than or
             equal to the first symbol's address, then some symbol in this
          /* This code assumes that the minimal symbols are sorted by
             ascending address values.  If the pc value is greater than or
             equal to the first symbol's address, then some symbol in this


@@ -197,14 +213,15 @@ lookup_minimal_symbol_by_pc (pc)
             Warning: this code is trickier than it would appear at first. */
 
          /* Should also requires that pc is <= end of objfile.  FIXME! */
             Warning: this code is trickier than it would appear at first. */
 
          /* Should also requires that pc is <= end of objfile.  FIXME! */

-         if (pc >= msymbol[lo].address)
+         if (pc >= SYMBOL_VALUE_ADDRESS (&msymbol[lo]))

            {
            {

-             while (msymbol[hi].address > pc)
+             while (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) > pc)

                {
                  /* pc is still strictly less than highest address */
                  /* Note "new" will always be >= lo */
                  new = (lo + hi) / 2;
                {
                  /* pc is still strictly less than highest address */
                  /* Note "new" will always be >= lo */
                  new = (lo + hi) / 2;

-                 if ((msymbol[new].address >= pc) || (lo == new))
+                 if ((SYMBOL_VALUE_ADDRESS (&msymbol[new]) >= pc) ||
+                     (lo == new))

                    {
                      hi = new;
                    }
                    {
                      hi = new;
                    }


@@ -217,13 +234,28 @@ lookup_minimal_symbol_by_pc (pc)
                 objfile's minimal symbol table.  See if it is the best one
                 overall. */
 
                 objfile's minimal symbol table.  See if it is the best one
                 overall. */
 

-             if ((best_symbol == NULL) ||
-                 (best_symbol -> address < msymbol[hi].address))
+             /* Skip any absolute symbols.  This is apparently what adb
+                and dbx do, and is needed for the CM-5.  There are two
+                known possible problems: (1) on ELF, apparently end, edata,
+                etc. are absolute.  Not sure ignoring them here is a big
+                deal, but if we want to use them, the fix would go in
+                elfread.c.  (2) I think shared library entry points on the
+                NeXT are absolute.  If we want special handling for this
+                it probably should be triggered by a special
+                mst_abs_or_lib or some such.  */
+             while (hi >= 0
+                    && msymbol[hi].type == mst_abs)
+               --hi;
+
+             if (hi >= 0
+                 && ((best_symbol == NULL) ||
+                     (SYMBOL_VALUE_ADDRESS (best_symbol) < 
+                      SYMBOL_VALUE_ADDRESS (&msymbol[hi]))))

                {
                  best_symbol = &msymbol[hi];
                }
            }
                {
                  best_symbol = &msymbol[hi];
                }
            }

-       }      
+       }

     }
   return (best_symbol);
 }
     }
   return (best_symbol);
 }


@@ -241,36 +273,70 @@ init_minimal_symbol_collection ()
 }
 
 void
 }
 
 void

-prim_record_minimal_symbol (name, address, ms_type)
+prim_record_minimal_symbol (name, address, ms_type, objfile)

      const char *name;
      CORE_ADDR address;
      enum minimal_symbol_type ms_type;
      const char *name;
      CORE_ADDR address;
      enum minimal_symbol_type ms_type;

+     struct objfile *objfile;

 {
 {

-  register struct msym_bunch *new;
+  int section;

 
 

-  if (msym_bunch_index == BUNCH_SIZE)
+  switch (ms_type)

     {
     {

-      new = (struct msym_bunch *) xmalloc (sizeof (struct msym_bunch));
-      msym_bunch_index = 0;
-      new -> next = msym_bunch;
-      msym_bunch = new;
+    case mst_text:
+    case mst_file_text:
+    case mst_solib_trampoline:
+      section = SECT_OFF_TEXT;
+      break;
+    case mst_data:
+    case mst_file_data:
+      section = SECT_OFF_DATA;
+      break;
+    case mst_bss:
+    case mst_file_bss:
+      section = SECT_OFF_BSS;
+      break;
+    default:
+      section = -1;

     }
     }

-  msym_bunch -> contents[msym_bunch_index].name = (char *) name;
-  msym_bunch -> contents[msym_bunch_index].address = address;
-  msym_bunch -> contents[msym_bunch_index].info = NULL;
-  msym_bunch -> contents[msym_bunch_index].type = ms_type;
-  msym_bunch_index++;
-  msym_count++;
+
+  prim_record_minimal_symbol_and_info (name, address, ms_type,
+                                      NULL, section, objfile);

 }
 
 void
 }
 
 void

-prim_record_minimal_symbol_and_info (name, address, ms_type, info)
+prim_record_minimal_symbol_and_info (name, address, ms_type, info, section,
+                                    objfile)

      const char *name;
      CORE_ADDR address;
      enum minimal_symbol_type ms_type;
      char *info;
      const char *name;
      CORE_ADDR address;
      enum minimal_symbol_type ms_type;
      char *info;

+     int section;
+     struct objfile *objfile;

 {
   register struct msym_bunch *new;
 {
   register struct msym_bunch *new;

+  register struct minimal_symbol *msymbol;
+
+  if (ms_type == mst_file_text)
+    {
+      /* Don't put gcc_compiled, __gnu_compiled_cplus, and friends into
+        the minimal symbols, because if there is also another symbol
+        at the same address (e.g. the first function of the file),
+        lookup_minimal_symbol_by_pc would have no way of getting the
+        right one.  */
+      if (name[0] == 'g'
+         && (strcmp (name, GCC_COMPILED_FLAG_SYMBOL) == 0
+             || strcmp (name, GCC2_COMPILED_FLAG_SYMBOL) == 0))
+       return;
+
+      {
+       const char *tempstring = name;
+       if (tempstring[0] == bfd_get_symbol_leading_char (objfile->obfd))
+         ++tempstring;
+       if (STREQN (tempstring, "__gnu_compiled", 14))
+         return;
+      }
+    }

 
   if (msym_bunch_index == BUNCH_SIZE)
     {
 
   if (msym_bunch_index == BUNCH_SIZE)
     {


@@ -279,12 +345,15 @@ prim_record_minimal_symbol_and_info (name, address, ms_type, info)
       new -> next = msym_bunch;
       msym_bunch = new;
     }
       new -> next = msym_bunch;
       msym_bunch = new;
     }

-  msym_bunch -> contents[msym_bunch_index].name = (char *) name;
-  msym_bunch -> contents[msym_bunch_index].address = address;
-  msym_bunch -> contents[msym_bunch_index].info = NULL;
-  msym_bunch -> contents[msym_bunch_index].type = ms_type;
-    /* FIXME:  This info, if it remains, needs its own field.  */
-  msym_bunch -> contents[msym_bunch_index].info = info;  /* FIXME! */
+  msymbol = &msym_bunch -> contents[msym_bunch_index];
+  SYMBOL_NAME (msymbol) = (char *) name;
+  SYMBOL_INIT_LANGUAGE_SPECIFIC (msymbol, language_unknown);
+  SYMBOL_VALUE_ADDRESS (msymbol) = address;
+  SYMBOL_SECTION (msymbol) = section;
+
+  MSYMBOL_TYPE (msymbol) = ms_type;
+  /* FIXME:  This info, if it remains, needs its own field.  */
+  MSYMBOL_INFO (msymbol) = info; /* FIXME! */

   msym_bunch_index++;
   msym_count++;
 }
   msym_bunch_index++;
   msym_count++;
 }


@@ -303,11 +372,11 @@ compare_minimal_symbols (fn1p, fn2p)
   fn1 = (const struct minimal_symbol *) fn1p;
   fn2 = (const struct minimal_symbol *) fn2p;
 
   fn1 = (const struct minimal_symbol *) fn1p;
   fn2 = (const struct minimal_symbol *) fn2p;
 

-  if (fn1 -> address < fn2 -> address)
+  if (SYMBOL_VALUE_ADDRESS (fn1) < SYMBOL_VALUE_ADDRESS (fn2))

     {
       return (-1);
     }
     {
       return (-1);
     }

-  else if (fn1 -> address > fn2 -> address)
+  else if (SYMBOL_VALUE_ADDRESS (fn1) > SYMBOL_VALUE_ADDRESS (fn2))

     {
       return (1);
     }
     {
       return (1);
     }


@@ -389,12 +458,13 @@ compact_minimal_symbols (msymbol, mcount)
       copyfrom = copyto = msymbol;
       while (copyfrom < msymbol + mcount - 1)
        {
       copyfrom = copyto = msymbol;
       while (copyfrom < msymbol + mcount - 1)
        {

-         if (copyfrom -> address == (copyfrom + 1) -> address
-             && (strcmp (copyfrom -> name, (copyfrom + 1) -> name) == 0))
+         if (SYMBOL_VALUE_ADDRESS (copyfrom) == 
+             SYMBOL_VALUE_ADDRESS ((copyfrom + 1)) &&
+             (STREQ (SYMBOL_NAME (copyfrom), SYMBOL_NAME ((copyfrom + 1)))))

            {
            {

-             if ((copyfrom + 1) -> type == mst_unknown)
+             if (MSYMBOL_TYPE((copyfrom + 1)) == mst_unknown)

                {
                {

-                 (copyfrom + 1) -> type = copyfrom -> type;
+                 MSYMBOL_TYPE ((copyfrom + 1)) = MSYMBOL_TYPE (copyfrom);

                }
              copyfrom++;
            }
                }
              copyfrom++;
            }


@@ -409,11 +479,28 @@ compact_minimal_symbols (msymbol, mcount)
   return (mcount);
 }
 
   return (mcount);
 }
 

-/* Add the minimal symbols in the existing bunches to the objfile's
-   official minimal symbol table.  99% of the time, this adds the
-   bunches to NO existing symbols.  Once in a while for shared
-   libraries, we add symbols (e.g. common symbols) to an existing
-   objfile.  */
+/* Add the minimal symbols in the existing bunches to the objfile's official
+   minimal symbol table.  In most cases there is no minimal symbol table yet
+   for this objfile, and the existing bunches are used to create one.  Once
+   in a while (for shared libraries for example), we add symbols (e.g. common
+   symbols) to an existing objfile.
+
+   Because of the way minimal symbols are collected, we generally have no way
+   of knowing what source language applies to any particular minimal symbol.
+   Specifically, we have no way of knowing if the minimal symbol comes from a
+   C++ compilation unit or not.  So for the sake of supporting cached
+   demangled C++ names, we have no choice but to try and demangle each new one
+   that comes in.  If the demangling succeeds, then we assume it is a C++
+   symbol and set the symbol's language and demangled name fields
+   appropriately.  Note that in order to avoid unnecessary demanglings, and
+   allocating obstack space that subsequently can't be freed for the demangled
+   names, we mark all newly added symbols with language_auto.  After
+   compaction of the minimal symbols, we go back and scan the entire minimal
+   symbol table looking for these new symbols.  For each new symbol we attempt
+   to demangle it, and if successful, record it as a language_cplus symbol
+   and cache the demangled form on the symbol obstack.  Symbols which don't
+   demangle are marked as language_unknown symbols, which inhibits future
+   attempts to demangle them if we later add more minimal symbols. */

 
 void
 install_minimal_symbols (objfile)
 
 void
 install_minimal_symbols (objfile)


@@ -424,6 +511,7 @@ install_minimal_symbols (objfile)
   register struct msym_bunch *bunch;
   register struct minimal_symbol *msymbols;
   int alloc_count;
   register struct msym_bunch *bunch;
   register struct minimal_symbol *msymbols;
   int alloc_count;

+  register char leading_char;

 
   if (msym_count > 0)
     {
 
   if (msym_count > 0)
     {


@@ -451,24 +539,18 @@ install_minimal_symbols (objfile)
         each bunch is full. */
       
       mcount = objfile->minimal_symbol_count;
         each bunch is full. */
       
       mcount = objfile->minimal_symbol_count;

+      leading_char = bfd_get_symbol_leading_char (objfile->obfd);

       
       for (bunch = msym_bunch; bunch != NULL; bunch = bunch -> next)
        {
          for (bindex = 0; bindex < msym_bunch_index; bindex++, mcount++)
            {
              msymbols[mcount] = bunch -> contents[bindex];
       
       for (bunch = msym_bunch; bunch != NULL; bunch = bunch -> next)
        {
          for (bindex = 0; bindex < msym_bunch_index; bindex++, mcount++)
            {
              msymbols[mcount] = bunch -> contents[bindex];

-#ifdef NAMES_HAVE_UNDERSCORE
-             if (msymbols[mcount].name[0] == '_')
-               {
-                 msymbols[mcount].name++;
-               }
-#endif
-#ifdef SOME_NAMES_HAVE_DOT
-             if (msymbols[mcount].name[0] == '.')
+             SYMBOL_LANGUAGE (&msymbols[mcount]) = language_auto;
+             if (SYMBOL_NAME (&msymbols[mcount])[0] == leading_char)

                {
                {

-                 msymbols[mcount].name++;
+                 SYMBOL_NAME(&msymbols[mcount])++;

                }
                }

-#endif

            }
          msym_bunch_index = BUNCH_SIZE;
        }
            }
          msym_bunch_index = BUNCH_SIZE;
        }


@@ -488,19 +570,19 @@ install_minimal_symbols (objfile)
       msymbols = (struct minimal_symbol *)
        obstack_finish (&objfile->symbol_obstack);
 
       msymbols = (struct minimal_symbol *)
        obstack_finish (&objfile->symbol_obstack);
 

-      /* We also terminate the minimal symbol table
-        with a "null symbol", which is *not* included in the size of
-        the table.  This makes it easier to find the end of the table
-        when we are handed a pointer to some symbol in the middle of it.
-         Zero out the fields in the "null symbol" allocated at the end
-        of the array.  Note that the symbol count does *not* include
-        this null symbol, which is why it is indexed by mcount and not
-        mcount-1. */
+      /* We also terminate the minimal symbol table with a "null symbol",
+        which is *not* included in the size of the table.  This makes it
+        easier to find the end of the table when we are handed a pointer
+        to some symbol in the middle of it.  Zero out the fields in the
+        "null symbol" allocated at the end of the array.  Note that the
+        symbol count does *not* include this null symbol, which is why it
+        is indexed by mcount and not mcount-1. */

 
 

-      msymbols[mcount].name = NULL;
-      msymbols[mcount].address = 0;
-      msymbols[mcount].info = NULL;
-      msymbols[mcount].type = mst_unknown;
+      SYMBOL_NAME (&msymbols[mcount]) = NULL;
+      SYMBOL_VALUE_ADDRESS (&msymbols[mcount]) = 0;
+      MSYMBOL_INFO (&msymbols[mcount]) = NULL;
+      MSYMBOL_TYPE (&msymbols[mcount]) = mst_unknown;
+      SYMBOL_INIT_LANGUAGE_SPECIFIC (&msymbols[mcount], language_unknown);

 
       /* Attach the minimal symbol table to the specified objfile.
         The strings themselves are also located in the symbol_obstack
 
       /* Attach the minimal symbol table to the specified objfile.
         The strings themselves are also located in the symbol_obstack


@@ -508,6 +590,59 @@ install_minimal_symbols (objfile)
 
       objfile -> minimal_symbol_count = mcount;
       objfile -> msymbols = msymbols;
 
       objfile -> minimal_symbol_count = mcount;
       objfile -> msymbols = msymbols;

+
+      /* Now walk through all the minimal symbols, selecting the newly added
+        ones and attempting to cache their C++ demangled names. */
+
+      for ( ; mcount-- > 0 ; msymbols++)
+       {
+         SYMBOL_INIT_DEMANGLED_NAME (msymbols, &objfile->symbol_obstack);
+       }
+    }
+}
+
+/* Check if PC is in a shared library trampoline code stub.
+   Return minimal symbol for the trampoline entry or NULL if PC is not
+   in a trampoline code stub.  */
+
+struct minimal_symbol *
+lookup_solib_trampoline_symbol_by_pc (pc)
+     CORE_ADDR pc;
+{
+  struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (pc);
+
+  if (msymbol != NULL && MSYMBOL_TYPE (msymbol) == mst_solib_trampoline)
+    return msymbol;
+  return NULL;
+}
+
+/* If PC is in a shared library trampoline code stub, return the
+   address of the `real' function belonging to the stub.
+   Return 0 if PC is not in a trampoline code stub or if the real
+   function is not found in the minimal symbol table.
+
+   We may fail to find the right function if a function with the
+   same name is defined in more than one shared library, but this
+   is considered bad programming style. We could return 0 if we find
+   a duplicate function in case this matters someday.  */
+
+CORE_ADDR
+find_solib_trampoline_target (pc)
+     CORE_ADDR pc;
+{
+  struct objfile *objfile;
+  struct minimal_symbol *msymbol;
+  struct minimal_symbol *tsymbol = lookup_solib_trampoline_symbol_by_pc (pc);
+
+  if (tsymbol != NULL)
+    {
+      ALL_MSYMBOLS (objfile, msymbol)
+       {
+         if (MSYMBOL_TYPE (msymbol) == mst_text
+             && STREQ (SYMBOL_NAME (msymbol), SYMBOL_NAME (tsymbol)))
+           return SYMBOL_VALUE_ADDRESS (msymbol);
+       }

     }
     }

+  return 0;

 }
 
 }