Index: x86-64-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/x86-64-tdep.c,v
retrieving revision 1.10
diff -c -3 -p -r1.10 x86-64-tdep.c
*** x86-64-tdep.c	2002/03/04 11:08:28	1.10
--- x86-64-tdep.c	2002/03/15 18:07:16
*************** x86_64_frameless_function_invocation (st
*** 759,769 ****
    return 0;
  }
  
! /* On x86_64 there are no reasonable prologs.  */
  CORE_ADDR
  x86_64_skip_prologue (CORE_ADDR pc)
  {
!   return pc;
  }
  
  /* Sequence of bytes for breakpoint instruction.  */
--- 759,815 ----
    return 0;
  }
  
! /* If a function with debugging information and known beginning
!    is detected, we will return pc of the next line in the source 
!    code. With this approach we effectively skip the prolog.  */
! 
! #define PROLOG_BUFSIZE 4
  CORE_ADDR
  x86_64_skip_prologue (CORE_ADDR pc)
  {
!    int i, firstline, currline;
!    struct symtab *v_symtab;
!    struct symbol *v_function;
!    CORE_ADDR      startaddr=0, endaddr=0;
!    
!    /* We will handle only functions beginning with:
!       55          pushq %rbp
!       48 89 e5    movq %rsp,%rbp 
!    */
!    unsigned char  prolog_expect[PROLOG_BUFSIZE]={0x55, 0x48, 0x89, 0xe5},
!                   prolog_buf[PROLOG_BUFSIZE];
!   
!    read_memory (pc, (char *) prolog_buf, PROLOG_BUFSIZE);
!   
!    /* First check, whether pc points to pushq %rbp, movq %rsp,%rbp.  */
!    for(i=0; i<PROLOG_BUFSIZE; i++)
!       if(prolog_expect[i] != prolog_buf[i])
!          return pc;
!   
!    v_symtab=find_pc_symtab(pc);
!    v_function=find_pc_function(pc);
!   
!    /* If pc doesn't point to a function with debuginfo, 
!       some of the following may be NULL.  */
!    if(!v_function || !v_symtab || !v_symtab->linetable || 
!       !v_function->ginfo.value.block)
!          return pc;
!    
!    firstline=v_function->line;
!    currline=firstline;
!    startaddr=v_function->ginfo.value.block->startaddr;
!    endaddr=v_function->ginfo.value.block->endaddr;
! 
!    for(i=0; i < v_symtab->linetable->nitems; i++)
!       if(v_symtab->linetable->item[i].line > firstline && 
!          v_symtab->linetable->item[i].pc < endaddr)
!       {
!          pc=v_symtab->linetable->item[i].pc;
!          currline=v_symtab->linetable->item[i].line;
!          break;
!       }
!  
!    return pc;
  }
  
  /* Sequence of bytes for breakpoint instruction.  */