xref: /openbsd/gnu/usr.bin/binutils/gprof/alpha.c (revision e5dd7070)
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	0x1a
41 #define	OP_BSR	0x34
42 
43 #define Jxx_FUNC_JMP		0
44 #define Jxx_FUNC_JSR		1
45 #define Jxx_FUNC_RET		2
46 #define Jxx_FUNC_JSR_COROUTINE	3
47 
48 #if 0
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 typedef union
52   {
53     struct
54       {
55 	unsigned other:26;
56 	unsigned op_code:6;
57       }
58     a;				/* any format */
59     struct
60       {
61 	int disp:21;
62 	unsigned ra:5;
63 	unsigned op_code:6;
64       }
65     b;				/* branch format */
66     struct
67       {
68 	int hint:14;
69 	unsigned func:2;
70 	unsigned rb:5;
71 	unsigned ra:5;
72 	unsigned op_code:6;
73       }
74     j;				/* jump format */
75   }
76 alpha_Instruction;
77 #endif
78 
79 static Sym indirect_child;
80 
81 void alpha_find_call PARAMS ((Sym *, bfd_vma, bfd_vma));
82 
83 /*
84  * On the Alpha we can only detect PC relative calls, which are
85  * usually generated for calls to functions within the same
86  * object file only.  This is still better than nothing, however.
87  * (In particular it should be possible to find functions that
88  *  potentially call integer division routines, for example.)
89  */
90 void
91 alpha_find_call (parent, p_lowpc, p_highpc)
92      Sym *parent;
93      bfd_vma p_lowpc;
94      bfd_vma p_highpc;
95 {
96   bfd_vma pc, dest_pc;
97   unsigned int insn;
98   Sym *child;
99 
100   if (indirect_child.name == NULL)
101     {
102       sym_init (&indirect_child);
103       indirect_child.name = _("<indirect child>");
104       indirect_child.cg.prop.fract = 1.0;
105       indirect_child.cg.cyc.head = &indirect_child;
106     }
107 
108   if (!core_text_space)
109     {
110       return;
111     }
112   if (p_lowpc < s_lowpc)
113     {
114       p_lowpc = s_lowpc;
115     }
116   if (p_highpc > s_highpc)
117     {
118       p_highpc = s_highpc;
119     }
120   DBG (CALLDEBUG, printf (_("[find_call] %s: 0x%lx to 0x%lx\n"),
121 			  parent->name, (unsigned long) p_lowpc,
122 			  (unsigned long) p_highpc));
123   for (pc = (p_lowpc + 3) & ~(bfd_vma) 3; pc < p_highpc; pc += 4)
124     {
125       insn = bfd_get_32 (core_bfd, ((unsigned char *) core_text_space
126 				    + pc - core_text_sect->vma));
127       switch (insn & (0x3f << 26))
128 	{
129 	case OP_Jxx << 26:
130 	  /*
131 	   * There is no simple and reliable way to determine the
132 	   * target of a jsr (the hint bits help, but there aren't
133 	   * enough bits to get a satisfactory hit rate).  Instead,
134 	   * for any indirect jump we simply add an arc from PARENT
135 	   * to INDIRECT_CHILD---that way the user it at least able
136 	   * to see that there are other calls as well.
137 	   */
138 	  if ((insn & (3 << 14)) == Jxx_FUNC_JSR << 14
139 	      || (insn & (3 << 14)) == Jxx_FUNC_JSR_COROUTINE << 14)
140 	    {
141 	      DBG (CALLDEBUG,
142 		   printf (_("[find_call] 0x%lx: jsr%s <indirect_child>\n"),
143 			   (unsigned long) pc,
144 			   ((insn & (3 << 14)) == Jxx_FUNC_JSR << 14
145 			    ? "" : "_coroutine")));
146 	      arc_add (parent, &indirect_child, (unsigned long) 0);
147 	    }
148 	  break;
149 
150 	case OP_BSR << 26:
151 	  DBG (CALLDEBUG,
152 	       printf (_("[find_call] 0x%lx: bsr"), (unsigned long) pc));
153 	  /*
154 	   * Regular PC relative addressing.  Check that this is the
155 	   * address of a function.  The linker sometimes redirects
156 	   * the entry point by 8 bytes to skip loading the global
157 	   * pointer, so we allow for either address:
158 	   */
159 	  dest_pc = pc + 4 + (((bfd_signed_vma) (insn & 0x1fffff)
160 			       ^ 0x100000) - 0x100000);
161 	  if (dest_pc >= s_lowpc && dest_pc <= s_highpc)
162 	    {
163 	      child = sym_lookup (&symtab, dest_pc);
164 	      DBG (CALLDEBUG,
165 		   printf (" 0x%lx\t; name=%s, addr=0x%lx",
166 			   (unsigned long) dest_pc, child->name,
167 			   (unsigned long) child->addr));
168 	      if (child->addr == dest_pc || child->addr == dest_pc - 8)
169 		{
170 		  DBG (CALLDEBUG, printf ("\n"));
171 		  /* a hit:  */
172 		  arc_add (parent, child, (unsigned long) 0);
173 		  continue;
174 		}
175 	    }
176 	  /*
177 	   * Something funny going on.
178 	   */
179 	  DBG (CALLDEBUG, printf ("\tbut it's a botch\n"));
180 	  break;
181 
182 	default:
183 	  break;
184 	}
185     }
186 }
187