1 /* Traditional frame unwind support, for GDB the GNU Debugger.
3 Copyright 2003 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
24 #include "trad-frame.h"
27 /* A traditional frame is unwound by analysing the function prologue
28 and using the information gathered to track registers. For
29 non-optimized frames, the technique is reliable (just need to check
30 for all potential instruction sequences). */
32 struct trad_frame_saved_reg *
33 trad_frame_alloc_saved_regs (struct frame_info *next_frame)
36 struct gdbarch *gdbarch = get_frame_arch (next_frame);
37 int numregs = NUM_REGS + NUM_PSEUDO_REGS;
38 struct trad_frame_saved_reg *this_saved_regs
39 = FRAME_OBSTACK_CALLOC (numregs, struct trad_frame_saved_reg);
40 for (regnum = 0; regnum < numregs; regnum++)
42 this_saved_regs[regnum].realreg = regnum;
43 this_saved_regs[regnum].addr = -1;
45 return this_saved_regs;
48 enum { REG_VALUE = -1, REG_UNKNOWN = -2 };
51 trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs[], int regnum)
53 return (this_saved_regs[regnum].realreg == REG_VALUE);
57 trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs[], int regnum)
59 return (this_saved_regs[regnum].realreg >= 0
60 && this_saved_regs[regnum].addr != -1);
64 trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs[],
67 return (this_saved_regs[regnum].realreg >= 0
68 && this_saved_regs[regnum].addr == -1);
72 trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs[],
73 int regnum, LONGEST val)
75 /* Make the REALREG invalid, indicating that the ADDR contains the
77 this_saved_regs[regnum].realreg = REG_VALUE;
78 this_saved_regs[regnum].addr = val;
82 trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs[],
85 /* Make the REALREG invalid, indicating that the value is not known. */
86 this_saved_regs[regnum].realreg = REG_UNKNOWN;
87 this_saved_regs[regnum].addr = -1;
91 trad_frame_prev_register (struct frame_info *next_frame,
92 struct trad_frame_saved_reg this_saved_regs[],
93 int regnum, int *optimizedp,
94 enum lval_type *lvalp, CORE_ADDR *addrp,
95 int *realregp, void *bufferp)
97 struct gdbarch *gdbarch = get_frame_arch (next_frame);
98 if (trad_frame_addr_p (this_saved_regs, regnum))
100 /* The register was saved in memory. */
102 *lvalp = lval_memory;
103 *addrp = this_saved_regs[regnum].addr;
107 /* Read the value in from memory. */
108 get_frame_memory (next_frame, this_saved_regs[regnum].addr, bufferp,
109 register_size (gdbarch, regnum));
112 else if (trad_frame_realreg_p (this_saved_regs, regnum))
114 /* Ask the next frame to return the value of the register. */
115 frame_register_unwind (next_frame, this_saved_regs[regnum].realreg,
116 optimizedp, lvalp, addrp, realregp, bufferp);
118 else if (trad_frame_value_p (this_saved_regs, regnum))
120 /* The register's value is available. */
126 store_unsigned_integer (bufferp, register_size (gdbarch, regnum),
127 this_saved_regs[regnum].addr);
131 error ("Register %s not available",
132 gdbarch_register_name (gdbarch, regnum));