gprof/alpha.c

   1 /*
   2  * Copyright (c) 1983, 1993, 1998
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29 #include "gprof.h"
  30 #include "search_list.h"
  31 #include "source.h"
  32 #include "symtab.h"
  33 #include "cg_arcs.h"
  34 #include "corefile.h"
  35 #include "hist.h"
  36
  37 /*
  38  * Opcodes of the call instructions:
  39  */
  40 #define OP_Jxx  0x1aU
  41 #define OP_BSR  0x34U
  42
  43 #define Jxx_FUNC_JMP            0U
  44 #define Jxx_FUNC_JSR            1U
  45 #define Jxx_FUNC_RET            2U
  46 #define Jxx_FUNC_JSR_COROUTINE  3U
  47
  48 /* *INDENT-OFF* */
  49 /* Here to document only.  We can't use this when cross compiling as
  50    the bitfield layout might not be the same as native.
  51
  52    typedef union
  53      {
  54        struct
  55          {
  56            unsigned other:26;
  57            unsigned op_code:6;
  58          }
  59        a;                               -- any format
  60        struct
  61          {
  62            int disp:21;
  63            unsigned ra:5;
  64            unsigned op_code:6;
  65          }
  66        b;                               -- branch format
  67        struct
  68          {
  69            int hint:14;
  70            unsigned func:2;
  71            unsigned rb:5;
  72            unsigned ra:5;
  73            unsigned op_code:6;
  74          }
  75        j;                               -- jump format
  76      }
  77     alpha_Instruction;
  78 */
  79 /* *INDENT-ON* */
  80
  81 static Sym indirect_child;
  82
  83 void alpha_find_call (Sym *, bfd_vma, bfd_vma);
  84
  85 /*
  86  * On the Alpha we can only detect PC relative calls, which are
  87  * usually generated for calls to functions within the same
  88  * object file only.  This is still better than nothing, however.
  89  * (In particular it should be possible to find functions that
  90  *  potentially call integer division routines, for example.)
  91  */
  92 void
  93 alpha_find_call (Sym *parent, bfd_vma p_lowpc, bfd_vma p_highpc)
  94 {
  95   bfd_vma pc, dest_pc;
  96   unsigned int insn;
  97   Sym *child;
  98
  99   if (indirect_child.name == NULL)
 100     {
 101       sym_init (&indirect_child);
 102       indirect_child.name = _("<indirect child>");
 103       indirect_child.cg.prop.fract = 1.0;
 104       indirect_child.cg.cyc.head = &indirect_child;
 105     }
 106
 107   DBG (CALLDEBUG, printf (_("[find_call] %s: 0x%lx to 0x%lx\n"),
 108                           parent->name, (unsigned long) p_lowpc,
 109                           (unsigned long) p_highpc));
 110   for (pc = (p_lowpc + 3) & ~(bfd_vma) 3; pc < p_highpc; pc += 4)
 111     {
 112       insn = bfd_get_32 (core_bfd, ((unsigned char *) core_text_space
 113                                     + pc - core_text_sect->vma));
 114       switch (insn & (0x3fU << 26))
 115         {
 116         case OP_Jxx << 26:
 117           /*
 118            * There is no simple and reliable way to determine the
 119            * target of a jsr (the hint bits help, but there aren't
 120            * enough bits to get a satisfactory hit rate).  Instead,
 121            * for any indirect jump we simply add an arc from PARENT
 122            * to INDIRECT_CHILD---that way the user it at least able
 123            * to see that there are other calls as well.
 124            */
 125           if ((insn & (3 << 14)) == Jxx_FUNC_JSR << 14
 126               || (insn & (3 << 14)) == Jxx_FUNC_JSR_COROUTINE << 14)
 127             {
 128               DBG (CALLDEBUG,
 129                    printf (_("[find_call] 0x%lx: jsr%s <indirect_child>\n"),
 130                            (unsigned long) pc,
 131                            ((insn & (3 << 14)) == Jxx_FUNC_JSR << 14
 132                             ? "" : "_coroutine")));
 133               arc_add (parent, &indirect_child, (unsigned long) 0);
 134             }
 135           break;
 136
 137         case OP_BSR << 26:
 138           DBG (CALLDEBUG,
 139                printf (_("[find_call] 0x%lx: bsr"), (unsigned long) pc));
 140           /*
 141            * Regular PC relative addressing.  Check that this is the
 142            * address of a function.  The linker sometimes redirects
 143            * the entry point by 8 bytes to skip loading the global
 144            * pointer, so we allow for either address:
 145            */
 146           dest_pc = pc + 4 + (((bfd_signed_vma) (insn & 0x1fffff)
 147                                ^ 0x100000) - 0x100000);
 148           if (hist_check_address (dest_pc))
 149             {
 150               child = sym_lookup (&symtab, dest_pc);
 151               if (child)
 152                 {
 153                   DBG (CALLDEBUG,
 154                        printf (" 0x%lx\t; name=%s, addr=0x%lx",
 155                                (unsigned long) dest_pc, child->name,
 156                                (unsigned long) child->addr));
 157                   if (child->addr == dest_pc || child->addr == dest_pc - 8)
 158                     {
 159                       DBG (CALLDEBUG, printf ("\n"));
 160                       /* a hit:  */
 161                       arc_add (parent, child, (unsigned long) 0);
 162                       continue;
 163                     }
 164                 }
 165             }
 166           /*
 167            * Something funny going on.
 168            */
 169           DBG (CALLDEBUG, printf ("\tbut it's a botch\n"));
 170           break;
 171
 172         default:
 173           break;
 174         }
 175     }
 176 }