/* Get info from stack frames;
convert between frames, blocks, functions and pc values.
- Copyright (C) 1986, 1987 Free Software Foundation, Inc.
+ Copyright 1986, 1987, 1988, 1989, 1991, 1994, 1995, 1996, 1997
+ Free Software Foundation, Inc.
-GDB is distributed in the hope that it will be useful, but WITHOUT ANY
-WARRANTY. No author or distributor accepts responsibility to anyone
-for the consequences of using it or for whether it serves any
-particular purpose or works at all, unless he says so in writing.
-Refer to the GDB General Public License for full details.
+This file is part of GDB.
-Everyone is granted permission to copy, modify and redistribute GDB,
-but only under the conditions described in the GDB General Public
-License. A copy of this license is supposed to have been given to you
-along with GDB so you can know your rights and responsibilities. It
-should be in a file named COPYING. Among other things, the copyright
-notice and this notice must be preserved on all copies.
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
-In other words, go ahead and share GDB, but don't try to stop
-anyone else from sharing it farther. Help stamp out software hoarding!
-*/
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "defs.h"
-#include "initialize.h"
-#include "param.h"
#include "symtab.h"
+#include "bfd.h"
+#include "symfile.h"
+#include "objfiles.h"
#include "frame.h"
+#include "gdbcore.h"
+#include "value.h" /* for read_register */
+#include "target.h" /* for target_has_stack */
+#include "inferior.h" /* for read_pc */
+#include "annotate.h"
+
+/* Is ADDR inside the startup file? Note that if your machine
+ has a way to detect the bottom of the stack, there is no need
+ to call this function from FRAME_CHAIN_VALID; the reason for
+ doing so is that some machines have no way of detecting bottom
+ of stack.
+
+ A PC of zero is always considered to be the bottom of the stack. */
+
+int
+inside_entry_file (addr)
+ CORE_ADDR addr;
+{
+ if (addr == 0)
+ return 1;
+ if (symfile_objfile == 0)
+ return 0;
+#if CALL_DUMMY_LOCATION == AT_ENTRY_POINT
+ /* Do not stop backtracing if the pc is in the call dummy
+ at the entry point. */
+/* FIXME: Won't always work with zeros for the last two arguments */
+ if (PC_IN_CALL_DUMMY (addr, 0, 0))
+ return 0;
+#endif
+ return (addr >= symfile_objfile -> ei.entry_file_lowpc &&
+ addr < symfile_objfile -> ei.entry_file_highpc);
+}
+
+/* Test a specified PC value to see if it is in the range of addresses
+ that correspond to the main() function. See comments above for why
+ we might want to do this.
-/* Address of end of first object file.
- This file is assumed to be a startup file
- and frames with pc's inside it
- are treated as nonexistent. */
+ Typically called from FRAME_CHAIN_VALID.
-CORE_ADDR first_object_file_end;
+ A PC of zero is always considered to be the bottom of the stack. */
-/* Address of innermost stack frame (contents of FP register) */
+int
+inside_main_func (pc)
+CORE_ADDR pc;
+{
+ if (pc == 0)
+ return 1;
+ if (symfile_objfile == 0)
+ return 0;
-static FRAME current_frame;
+ /* If the addr range is not set up at symbol reading time, set it up now.
+ This is for FRAME_CHAIN_VALID_ALTERNATE. I do this for coff, because
+ it is unable to set it up and symbol reading time. */
-struct block *block_for_pc ();
-CORE_ADDR get_pc_function_start ();
+ if (symfile_objfile -> ei.main_func_lowpc == INVALID_ENTRY_LOWPC &&
+ symfile_objfile -> ei.main_func_highpc == INVALID_ENTRY_HIGHPC)
+ {
+ struct symbol *mainsym;
-START_FILE
+ mainsym = lookup_symbol ("main", NULL, VAR_NAMESPACE, NULL, NULL);
+ if (mainsym && SYMBOL_CLASS(mainsym) == LOC_BLOCK)
+ {
+ symfile_objfile->ei.main_func_lowpc = BLOCK_START (SYMBOL_BLOCK_VALUE (mainsym));
+ symfile_objfile->ei.main_func_highpc = BLOCK_END (SYMBOL_BLOCK_VALUE (mainsym));
+ }
+ }
+ return (symfile_objfile -> ei.main_func_lowpc <= pc &&
+ symfile_objfile -> ei.main_func_highpc > pc);
+}
+
+/* Test a specified PC value to see if it is in the range of addresses
+ that correspond to the process entry point function. See comments
+ in objfiles.h for why we might want to do this.
+
+ Typically called from FRAME_CHAIN_VALID.
+
+ A PC of zero is always considered to be the bottom of the stack. */
+
+int
+inside_entry_func (pc)
+CORE_ADDR pc;
+{
+ if (pc == 0)
+ return 1;
+ if (symfile_objfile == 0)
+ return 0;
+#if CALL_DUMMY_LOCATION == AT_ENTRY_POINT
+ /* Do not stop backtracing if the pc is in the call dummy
+ at the entry point. */
+/* FIXME: Won't always work with zeros for the last two arguments */
+ if (PC_IN_CALL_DUMMY (pc, 0, 0))
+ return 0;
+#endif
+ return (symfile_objfile -> ei.entry_func_lowpc <= pc &&
+ symfile_objfile -> ei.entry_func_highpc > pc);
+}
+
+/* Info about the innermost stack frame (contents of FP register) */
+
+static struct frame_info *current_frame;
+
+/* Cache for frame addresses already read by gdb. Valid only while
+ inferior is stopped. Control variables for the frame cache should
+ be local to this module. */
+
+struct obstack frame_cache_obstack;
/* Return the innermost (currently executing) stack frame. */
-FRAME
+struct frame_info *
get_current_frame ()
{
- /* We assume its address is kept in a general register;
- param.h says which register. */
-
+ if (current_frame == NULL)
+ {
+ if (target_has_stack)
+ current_frame = create_new_frame (read_fp (), read_pc ());
+ else
+ error ("No stack.");
+ }
return current_frame;
}
void
set_current_frame (frame)
- FRAME frame;
+ struct frame_info *frame;
{
current_frame = frame;
}
-/* Return the frame that called FRAME.
- If FRAME is the original frame (it has no caller), return 0. */
+/* Create an arbitrary (i.e. address specified by user) or innermost frame.
+ Always returns a non-NULL value. */
+
+struct frame_info *
+create_new_frame (addr, pc)
+ CORE_ADDR addr;
+ CORE_ADDR pc;
+{
+ struct frame_info *fi;
+ char *name;
+
+ fi = (struct frame_info *)
+ obstack_alloc (&frame_cache_obstack,
+ sizeof (struct frame_info));
+
+ /* Arbitrary frame */
+ fi->next = NULL;
+ fi->prev = NULL;
+ fi->frame = addr;
+ fi->pc = pc;
+ find_pc_partial_function (pc, &name, (CORE_ADDR *)NULL,(CORE_ADDR *)NULL);
+ fi->signal_handler_caller = IN_SIGTRAMP (fi->pc, name);
+
+#ifdef INIT_EXTRA_FRAME_INFO
+ INIT_EXTRA_FRAME_INFO (0, fi);
+#endif
+
+ return fi;
+}
+
+/* Return the frame that called FI.
+ If FI is the original frame (it has no caller), return 0. */
-FRAME
+struct frame_info *
get_prev_frame (frame)
- FRAME frame;
-{
- CORE_ADDR pointer;
- /* The caller of "no frame" is the innermost frame. */
- if (frame == 0)
- return get_current_frame ();
-
- /* Two macros defined in param.h specify the machine-dependent
- actions to be performed here. */
- /* First, get the frame's chain-pointer.
- If that is zero, the frame is the outermost frame. */
- pointer = FRAME_CHAIN (frame);
- if (!FRAME_CHAIN_VALID (pointer, frame))
- return 0;
- /* If frame has a caller, combine the chain pointer and the frame's own
- address to get the address of the caller. */
- return FRAME_CHAIN_COMBINE (pointer, frame);
+ struct frame_info *frame;
+{
+ return get_prev_frame_info (frame);
}
-/* Return a structure containing various interesting information
- about a specified stack frame. */
+/* Return the frame that FRAME calls (NULL if FRAME is the innermost
+ frame). */
-struct frame_info
-get_frame_info (frame)
- FRAME frame;
+struct frame_info *
+get_next_frame (frame)
+ struct frame_info *frame;
{
- struct frame_info val;
- FRAME current = get_current_frame ();
- register FRAME frame1;
+ return frame->next;
+}
- val.frame = frame;
+/* Flush the entire frame cache. */
- if (frame == current)
+void
+flush_cached_frames ()
+{
+ /* Since we can't really be sure what the first object allocated was */
+ obstack_free (&frame_cache_obstack, 0);
+ obstack_init (&frame_cache_obstack);
+
+ current_frame = NULL; /* Invalidate cache */
+ select_frame (NULL, -1);
+ annotate_frames_invalid ();
+}
+
+/* Flush the frame cache, and start a new one if necessary. */
+
+void
+reinit_frame_cache ()
+{
+ flush_cached_frames ();
+
+ /* FIXME: The inferior_pid test is wrong if there is a corefile. */
+ if (inferior_pid != 0)
{
- val.pc = read_pc ();
- val.next_frame = 0;
+ select_frame (get_current_frame (), 0);
}
- else
- {
- for (frame1 = current; frame1; frame1 = get_prev_frame (frame1))
- {
- QUIT;
- if (frame1 == frame)
- break;
+}
- val.pc = FRAME_SAVED_PC (frame1);
- val.next_frame = frame1;
- }
- }
+/* If a machine allows frameless functions, it should define a macro
+ FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) in param.h. FI is the struct
+ frame_info for the frame, and FRAMELESS should be set to nonzero
+ if it represents a frameless function invocation. */
+
+/* Return nonzero if the function for this frame lacks a prologue. Many
+ machines can define FRAMELESS_FUNCTION_INVOCATION to just call this
+ function. */
- return val;
+int
+frameless_look_for_prologue (frame)
+ struct frame_info *frame;
+{
+ CORE_ADDR func_start, after_prologue;
+ func_start = get_pc_function_start (frame->pc);
+ if (func_start)
+ {
+ func_start += FUNCTION_START_OFFSET;
+ after_prologue = func_start;
+#ifdef SKIP_PROLOGUE_FRAMELESS_P
+ /* This is faster, since only care whether there *is* a prologue,
+ not how long it is. */
+ SKIP_PROLOGUE_FRAMELESS_P (after_prologue);
+#else
+ SKIP_PROLOGUE (after_prologue);
+#endif
+ return after_prologue == func_start;
+ }
+ else if (frame->pc == 0)
+ /* A frame with a zero PC is usually created by dereferencing a NULL
+ function pointer, normally causing an immediate core dump of the
+ inferior. Mark function as frameless, as the inferior has no chance
+ of setting up a stack frame. */
+ return 1;
+ else
+ /* If we can't find the start of the function, we don't really
+ know whether the function is frameless, but we should be able
+ to get a reasonable (i.e. best we can do under the
+ circumstances) backtrace by saying that it isn't. */
+ return 0;
}
-/* Return a structure containing various interesting information
- about the frame that called FRAME.
+/* Default a few macros that people seldom redefine. */
+
+#if !defined (INIT_FRAME_PC)
+#define INIT_FRAME_PC(fromleaf, prev) \
+ prev->pc = (fromleaf ? SAVED_PC_AFTER_CALL (prev->next) : \
+ prev->next ? FRAME_SAVED_PC (prev->next) : read_pc ());
+#endif
- This is much faster than get_frame_info (get_prev_frame (FRAME))
- because it does not need to search the entire stack
- to find the frame called by the one being described -- that is FRAME. */
+#ifndef FRAME_CHAIN_COMBINE
+#define FRAME_CHAIN_COMBINE(chain, thisframe) (chain)
+#endif
+
+/* Return a structure containing various interesting information
+ about the frame that called NEXT_FRAME. Returns NULL
+ if there is no such frame. */
-struct frame_info
+struct frame_info *
get_prev_frame_info (next_frame)
- FRAME next_frame;
+ struct frame_info *next_frame;
{
- struct frame_info val;
- register FRAME frame = get_prev_frame (next_frame);
+ CORE_ADDR address = 0;
+ struct frame_info *prev;
+ int fromleaf = 0;
+ char *name;
- val.frame = frame;
- val.next_frame = next_frame;
+ /* If the requested entry is in the cache, return it.
+ Otherwise, figure out what the address should be for the entry
+ we're about to add to the cache. */
- if (next_frame == 0)
+ if (!next_frame)
{
- val.pc = read_pc ();
+#if 0
+ /* This screws value_of_variable, which just wants a nice clean
+ NULL return from block_innermost_frame if there are no frames.
+ I don't think I've ever seen this message happen otherwise.
+ And returning NULL here is a perfectly legitimate thing to do. */
+ if (!current_frame)
+ {
+ error ("You haven't set up a process's stack to examine.");
+ }
+#endif
+
+ return current_frame;
+ }
+
+ /* If we have the prev one, return it */
+ if (next_frame->prev)
+ return next_frame->prev;
+
+ /* On some machines it is possible to call a function without
+ setting up a stack frame for it. On these machines, we
+ define this macro to take two args; a frameinfo pointer
+ identifying a frame and a variable to set or clear if it is
+ or isn't leafless. */
+#ifdef FRAMELESS_FUNCTION_INVOCATION
+ /* Still don't want to worry about this except on the innermost
+ frame. This macro will set FROMLEAF if NEXT_FRAME is a
+ frameless function invocation. */
+ if (!(next_frame->next))
+ {
+ FRAMELESS_FUNCTION_INVOCATION (next_frame, fromleaf);
+ if (fromleaf)
+ address = FRAME_FP (next_frame);
}
- else
+#endif
+
+ if (!fromleaf)
+ {
+ /* Two macros defined in tm.h specify the machine-dependent
+ actions to be performed here.
+ First, get the frame's chain-pointer.
+ If that is zero, the frame is the outermost frame or a leaf
+ called by the outermost frame. This means that if start
+ calls main without a frame, we'll return 0 (which is fine
+ anyway).
+
+ Nope; there's a problem. This also returns when the current
+ routine is a leaf of main. This is unacceptable. We move
+ this to after the ffi test; I'd rather have backtraces from
+ start go curfluy than have an abort called from main not show
+ main. */
+ address = FRAME_CHAIN (next_frame);
+ if (!FRAME_CHAIN_VALID (address, next_frame))
+ return 0;
+ address = FRAME_CHAIN_COMBINE (address, next_frame);
+ }
+ if (address == 0)
+ return 0;
+
+ prev = (struct frame_info *)
+ obstack_alloc (&frame_cache_obstack,
+ sizeof (struct frame_info));
+
+ if (next_frame)
+ next_frame->prev = prev;
+ prev->next = next_frame;
+ prev->prev = (struct frame_info *) 0;
+ prev->frame = address;
+ prev->signal_handler_caller = 0;
+
+/* This change should not be needed, FIXME! We should
+ determine whether any targets *need* INIT_FRAME_PC to happen
+ after INIT_EXTRA_FRAME_INFO and come up with a simple way to
+ express what goes on here.
+
+ INIT_EXTRA_FRAME_INFO is called from two places: create_new_frame
+ (where the PC is already set up) and here (where it isn't).
+ INIT_FRAME_PC is only called from here, always after
+ INIT_EXTRA_FRAME_INFO.
+
+ The catch is the MIPS, where INIT_EXTRA_FRAME_INFO requires the PC
+ value (which hasn't been set yet). Some other machines appear to
+ require INIT_EXTRA_FRAME_INFO before they can do INIT_FRAME_PC. Phoo.
+
+ We shouldn't need INIT_FRAME_PC_FIRST to add more complication to
+ an already overcomplicated part of GDB. gnu@cygnus.com, 15Sep92.
+
+ Assuming that some machines need INIT_FRAME_PC after
+ INIT_EXTRA_FRAME_INFO, one possible scheme:
+
+ SETUP_INNERMOST_FRAME()
+ Default version is just create_new_frame (read_fp ()),
+ read_pc ()). Machines with extra frame info would do that (or the
+ local equivalent) and then set the extra fields.
+ SETUP_ARBITRARY_FRAME(argc, argv)
+ Only change here is that create_new_frame would no longer init extra
+ frame info; SETUP_ARBITRARY_FRAME would have to do that.
+ INIT_PREV_FRAME(fromleaf, prev)
+ Replace INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC. This should
+ also return a flag saying whether to keep the new frame, or
+ whether to discard it, because on some machines (e.g. mips) it
+ is really awkward to have FRAME_CHAIN_VALID called *before*
+ INIT_EXTRA_FRAME_INFO (there is no good way to get information
+ deduced in FRAME_CHAIN_VALID into the extra fields of the new frame).
+ std_frame_pc(fromleaf, prev)
+ This is the default setting for INIT_PREV_FRAME. It just does what
+ the default INIT_FRAME_PC does. Some machines will call it from
+ INIT_PREV_FRAME (either at the beginning, the end, or in the middle).
+ Some machines won't use it.
+ kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
+
+#ifdef INIT_FRAME_PC_FIRST
+ INIT_FRAME_PC_FIRST (fromleaf, prev);
+#endif
+
+#ifdef INIT_EXTRA_FRAME_INFO
+ INIT_EXTRA_FRAME_INFO(fromleaf, prev);
+#endif
+
+ /* This entry is in the frame queue now, which is good since
+ FRAME_SAVED_PC may use that queue to figure out its value
+ (see tm-sparc.h). We want the pc saved in the inferior frame. */
+ INIT_FRAME_PC(fromleaf, prev);
+
+ /* If ->frame and ->pc are unchanged, we are in the process of getting
+ ourselves into an infinite backtrace. Some architectures check this
+ in FRAME_CHAIN or thereabouts, but it seems like there is no reason
+ this can't be an architecture-independent check. */
+ if (next_frame != NULL)
{
- val.pc = FRAME_SAVED_PC (next_frame);
+ if (prev->frame == next_frame->frame
+ && prev->pc == next_frame->pc)
+ {
+ next_frame->prev = NULL;
+ obstack_free (&frame_cache_obstack, prev);
+ return NULL;
+ }
}
- return val;
+ find_pc_partial_function (prev->pc, &name,
+ (CORE_ADDR *)NULL,(CORE_ADDR *)NULL);
+ if (IN_SIGTRAMP (prev->pc, name))
+ prev->signal_handler_caller = 1;
+
+ return prev;
}
CORE_ADDR
get_frame_pc (frame)
- FRAME frame;
+ struct frame_info *frame;
{
- struct frame_info fi;
- fi = get_frame_info (frame);
- return fi.pc;
+ return frame->pc;
}
+#if defined (FRAME_FIND_SAVED_REGS)
/* Find the addresses in which registers are saved in FRAME. */
void
-get_frame_saved_regs (frame_info_addr, saved_regs_addr)
- struct frame_info *frame_info_addr;
+get_frame_saved_regs (frame, saved_regs_addr)
+ struct frame_info *frame;
struct frame_saved_regs *saved_regs_addr;
{
- FRAME_FIND_SAVED_REGS (*frame_info_addr, *saved_regs_addr);
+ FRAME_FIND_SAVED_REGS (frame, *saved_regs_addr);
}
+#endif
/* Return the innermost lexical block in execution
in a specified stack frame. The frame address is assumed valid. */
struct block *
get_frame_block (frame)
- FRAME frame;
+ struct frame_info *frame;
{
- struct frame_info fi;
+ CORE_ADDR pc;
- fi = get_frame_info (frame);
- return block_for_pc (fi.pc);
+ pc = frame->pc;
+ if (frame->next != 0 && frame->next->signal_handler_caller == 0)
+ /* We are not in the innermost frame and we were not interrupted
+ by a signal. We need to subtract one to get the correct block,
+ in case the call instruction was the last instruction of the block.
+ If there are any machines on which the saved pc does not point to
+ after the call insn, we probably want to make frame->pc point after
+ the call insn anyway. */
+ --pc;
+ return block_for_pc (pc);
}
struct block *
get_pc_function_start (pc)
CORE_ADDR pc;
{
- register struct block *bl = block_for_pc (pc);
+ register struct block *bl;
register struct symbol *symbol;
- if (bl == 0)
+ register struct minimal_symbol *msymbol;
+ CORE_ADDR fstart;
+
+ if ((bl = block_for_pc (pc)) != NULL &&
+ (symbol = block_function (bl)) != NULL)
{
- register int misc_index = find_pc_misc_function (pc);
- if (misc_index >= 0)
- return misc_function_vector[misc_index].address;
- return 0;
+ bl = SYMBOL_BLOCK_VALUE (symbol);
+ fstart = BLOCK_START (bl);
+ }
+ else if ((msymbol = lookup_minimal_symbol_by_pc (pc)) != NULL)
+ {
+ fstart = SYMBOL_VALUE_ADDRESS (msymbol);
+ }
+ else
+ {
+ fstart = 0;
}
- symbol = block_function (bl);
- bl = SYMBOL_BLOCK_VALUE (symbol);
- return BLOCK_START (bl);
-}
+ return (fstart);
+}
/* Return the symbol for the function executing in frame FRAME. */
struct symbol *
get_frame_function (frame)
- FRAME frame;
+ struct frame_info *frame;
{
register struct block *bl = get_frame_block (frame);
if (bl == 0)
return block_function (bl);
}
\f
-/* Return the innermost lexical block containing the specified pc value,
- or 0 if there is none. */
+/* Return the blockvector immediately containing the innermost lexical block
+ containing the specified pc value, or 0 if there is none.
+ PINDEX is a pointer to the index value of the block. If PINDEX
+ is NULL, we don't pass this information back to the caller. */
-struct block *
-block_for_pc (pc)
+struct blockvector *
+blockvector_for_pc (pc, pindex)
register CORE_ADDR pc;
+ int *pindex;
{
register struct block *b;
register int bot, top, half;
struct blockvector *bl;
/* First search all symtabs for one whose file contains our pc */
-
- for (s = symtab_list; s; s = s->next)
- {
- bl = BLOCKVECTOR (s);
- b = BLOCKVECTOR_BLOCK (bl, 0);
- if (BLOCK_START (b) <= pc
- && BLOCK_END (b) > pc)
- break;
- }
-
+ s = find_pc_symtab (pc);
if (s == 0)
return 0;
+ bl = BLOCKVECTOR (s);
+ b = BLOCKVECTOR_BLOCK (bl, 0);
+
/* Then search that symtab for the smallest block that wins. */
/* Use binary search to find the last block that starts before PC. */
{
b = BLOCKVECTOR_BLOCK (bl, bot);
if (BLOCK_END (b) > pc)
- return b;
+ {
+ if (pindex)
+ *pindex = bot;
+ return bl;
+ }
bot--;
}
return 0;
}
+/* Return the innermost lexical block containing the specified pc value,
+ or 0 if there is none. */
+
+struct block *
+block_for_pc (pc)
+ register CORE_ADDR pc;
+{
+ register struct blockvector *bl;
+ int index;
+
+ bl = blockvector_for_pc (pc, &index);
+ if (bl)
+ return BLOCKVECTOR_BLOCK (bl, index);
+ return 0;
+}
+
/* Return the function containing pc value PC.
Returns 0 if function is not known. */
return block_function (b);
}
-/* Find the misc function whose address is the largest
- while being less than PC. Return its index in misc_function_vector.
- Returns -1 if PC is not in suitable range. */
+/* These variables are used to cache the most recent result
+ * of find_pc_partial_function. */
+
+static CORE_ADDR cache_pc_function_low = 0;
+static CORE_ADDR cache_pc_function_high = 0;
+static char *cache_pc_function_name = 0;
+
+/* Clear cache, e.g. when symbol table is discarded. */
+
+void
+clear_pc_function_cache()
+{
+ cache_pc_function_low = 0;
+ cache_pc_function_high = 0;
+ cache_pc_function_name = (char *)0;
+}
+
+/* Finds the "function" (text symbol) that is smaller than PC but
+ greatest of all of the potential text symbols. Sets *NAME and/or
+ *ADDRESS conditionally if that pointer is non-null. If ENDADDR is
+ non-null, then set *ENDADDR to be the end of the function
+ (exclusive), but passing ENDADDR as non-null means that the
+ function might cause symbols to be read. This function either
+ succeeds or fails (not halfway succeeds). If it succeeds, it sets
+ *NAME, *ADDRESS, and *ENDADDR to real information and returns 1.
+ If it fails, it sets *NAME, *ADDRESS, and *ENDADDR to zero
+ and returns 0. */
int
-find_pc_misc_function (pc)
+find_pc_partial_function (pc, name, address, endaddr)
CORE_ADDR pc;
+ char **name;
+ CORE_ADDR *address;
+ CORE_ADDR *endaddr;
{
- register int i;
+ struct partial_symtab *pst;
+ struct symbol *f;
+ struct minimal_symbol *msymbol;
+ struct partial_symbol *psb;
+ struct obj_section *sec;
+
+ if (pc >= cache_pc_function_low && pc < cache_pc_function_high)
+ goto return_cached_value;
+
+ /* If sigtramp is in the u area, it counts as a function (especially
+ important for step_1). */
+#if defined SIGTRAMP_START
+ if (IN_SIGTRAMP (pc, (char *)NULL))
+ {
+ cache_pc_function_low = SIGTRAMP_START (pc);
+ cache_pc_function_high = SIGTRAMP_END (pc);
+ cache_pc_function_name = "<sigtramp>";
+
+ goto return_cached_value;
+ }
+#endif
- /* Note that the last thing in the vector is always _etext. */
- for (i = 0; i < misc_function_count; i++)
+ msymbol = lookup_minimal_symbol_by_pc (pc);
+ pst = find_pc_psymtab (pc);
+ if (pst)
{
- if (pc < misc_function_vector[i].address)
- return i - 1;
+ /* Need to read the symbols to get a good value for the end address. */
+ if (endaddr != NULL && !pst->readin)
+ {
+ /* Need to get the terminal in case symbol-reading produces
+ output. */
+ target_terminal_ours_for_output ();
+ PSYMTAB_TO_SYMTAB (pst);
+ }
+
+ if (pst->readin)
+ {
+ /* Checking whether the msymbol has a larger value is for the
+ "pathological" case mentioned in print_frame_info. */
+ f = find_pc_function (pc);
+ if (f != NULL
+ && (msymbol == NULL
+ || (BLOCK_START (SYMBOL_BLOCK_VALUE (f))
+ >= SYMBOL_VALUE_ADDRESS (msymbol))))
+ {
+ cache_pc_function_low = BLOCK_START (SYMBOL_BLOCK_VALUE (f));
+ cache_pc_function_high = BLOCK_END (SYMBOL_BLOCK_VALUE (f));
+ cache_pc_function_name = SYMBOL_NAME (f);
+ goto return_cached_value;
+ }
+ }
+ else
+ {
+ /* Now that static symbols go in the minimal symbol table, perhaps
+ we could just ignore the partial symbols. But at least for now
+ we use the partial or minimal symbol, whichever is larger. */
+ psb = find_pc_psymbol (pst, pc);
+
+ if (psb
+ && (msymbol == NULL ||
+ (SYMBOL_VALUE_ADDRESS (psb)
+ >= SYMBOL_VALUE_ADDRESS (msymbol))))
+ {
+ /* This case isn't being cached currently. */
+ if (address)
+ *address = SYMBOL_VALUE_ADDRESS (psb);
+ if (name)
+ *name = SYMBOL_NAME (psb);
+ /* endaddr non-NULL can't happen here. */
+ return 1;
+ }
+ }
+ }
+
+ /* Not in the normal symbol tables, see if the pc is in a known section.
+ If it's not, then give up. This ensures that anything beyond the end
+ of the text seg doesn't appear to be part of the last function in the
+ text segment. */
+
+ sec = find_pc_section (pc);
+
+ if (!sec)
+ msymbol = NULL;
+
+ /* Must be in the minimal symbol table. */
+ if (msymbol == NULL)
+ {
+ /* No available symbol. */
+ if (name != NULL)
+ *name = 0;
+ if (address != NULL)
+ *address = 0;
+ if (endaddr != NULL)
+ *endaddr = 0;
+ return 0;
}
- return -1;
+
+ cache_pc_function_low = SYMBOL_VALUE_ADDRESS (msymbol);
+ cache_pc_function_name = SYMBOL_NAME (msymbol);
+
+ /* Use the lesser of the next minimal symbol, or the end of the section, as
+ the end of the function. */
+
+ if (SYMBOL_NAME (msymbol + 1) != NULL
+ && SYMBOL_VALUE_ADDRESS (msymbol + 1) < sec->endaddr)
+ cache_pc_function_high = SYMBOL_VALUE_ADDRESS (msymbol + 1);
+ else
+ /* We got the start address from the last msymbol in the objfile.
+ So the end address is the end of the section. */
+ cache_pc_function_high = sec->endaddr;
+
+ return_cached_value:
+ if (address)
+ *address = cache_pc_function_low;
+ if (name)
+ *name = cache_pc_function_name;
+ if (endaddr)
+ *endaddr = cache_pc_function_high;
+ return 1;
}
-/* Return the innermost stack frame executing inside of the specified block,
- or zero if there is no such frame. */
+/* Return the innermost stack frame executing inside of BLOCK,
+ or NULL if there is no such frame. If BLOCK is NULL, just return NULL. */
-FRAME
+struct frame_info *
block_innermost_frame (block)
struct block *block;
{
- struct frame_info fi;
- register FRAME frame;
- register CORE_ADDR start = BLOCK_START (block);
- register CORE_ADDR end = BLOCK_END (block);
+ struct frame_info *frame;
+ register CORE_ADDR start;
+ register CORE_ADDR end;
- frame = 0;
+ if (block == NULL)
+ return NULL;
+
+ start = BLOCK_START (block);
+ end = BLOCK_END (block);
+
+ frame = NULL;
while (1)
{
- fi = get_prev_frame_info (frame);
- frame = fi.frame;
- if (frame == 0)
- return 0;
- if (fi.pc >= start && fi.pc < end)
+ frame = get_prev_frame (frame);
+ if (frame == NULL)
+ return NULL;
+ if (frame->pc >= start && frame->pc < end)
return frame;
}
}
-static
-initialize ()
+/* Return the full FRAME which corresponds to the given CORE_ADDR
+ or NULL if no FRAME on the chain corresponds to CORE_ADDR. */
+
+struct frame_info *
+find_frame_addr_in_frame_chain (frame_addr)
+ CORE_ADDR frame_addr;
+{
+ struct frame_info *frame = NULL;
+
+ if (frame_addr == (CORE_ADDR)0)
+ return NULL;
+
+ while (1)
+ {
+ frame = get_prev_frame (frame);
+ if (frame == NULL)
+ return NULL;
+ if (FRAME_FP (frame) == frame_addr)
+ return frame;
+ }
+}
+
+#ifdef SIGCONTEXT_PC_OFFSET
+/* Get saved user PC for sigtramp from sigcontext for BSD style sigtramp. */
+
+CORE_ADDR
+sigtramp_saved_pc (frame)
+ struct frame_info *frame;
+{
+ CORE_ADDR sigcontext_addr;
+ char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT];
+ int ptrbytes = TARGET_PTR_BIT / TARGET_CHAR_BIT;
+ int sigcontext_offs = (2 * TARGET_INT_BIT) / TARGET_CHAR_BIT;
+
+ /* Get sigcontext address, it is the third parameter on the stack. */
+ if (frame->next)
+ sigcontext_addr = read_memory_integer (FRAME_ARGS_ADDRESS (frame->next)
+ + FRAME_ARGS_SKIP
+ + sigcontext_offs,
+ ptrbytes);
+ else
+ sigcontext_addr = read_memory_integer (read_register (SP_REGNUM)
+ + sigcontext_offs,
+ ptrbytes);
+
+ /* Don't cause a memory_error when accessing sigcontext in case the stack
+ layout has changed or the stack is corrupt. */
+ target_read_memory (sigcontext_addr + SIGCONTEXT_PC_OFFSET, buf, ptrbytes);
+ return extract_unsigned_integer (buf, ptrbytes);
+}
+#endif /* SIGCONTEXT_PC_OFFSET */
+
+#ifdef USE_GENERIC_DUMMY_FRAMES
+
+/*
+ * GENERIC DUMMY FRAMES
+ *
+ * The following code serves to maintain the dummy stack frames for
+ * inferior function calls (ie. when gdb calls into the inferior via
+ * call_function_by_hand). This code saves the machine state before
+ * the call in host memory, so we must maintain an independant stack
+ * and keep it consistant etc. I am attempting to make this code
+ * generic enough to be used by many targets.
+ *
+ * The cheapest and most generic way to do CALL_DUMMY on a new target
+ * is probably to define CALL_DUMMY to be empty, CALL_DUMMY_LENGTH to zero,
+ * and CALL_DUMMY_LOCATION to AT_ENTRY. Then you must remember to define
+ * PUSH_RETURN_ADDRESS, because no call instruction will be being
+ * executed by the target.
+ */
+
+static struct dummy_frame *dummy_frame_stack = NULL;
+
+/* Function: find_dummy_frame(pc, fp, sp)
+ Search the stack of dummy frames for one matching the given PC, FP and SP.
+ This is the work-horse for pc_in_call_dummy and read_register_dummy */
+
+char *
+generic_find_dummy_frame (pc, fp)
+ CORE_ADDR pc;
+ CORE_ADDR fp;
+{
+ struct dummy_frame * dummyframe;
+
+ if (pc != entry_point_address ())
+ return 0;
+
+ for (dummyframe = dummy_frame_stack; dummyframe != NULL;
+ dummyframe = dummyframe->next)
+ if (fp == dummyframe->fp || fp == dummyframe->sp)
+ /* The frame in question lies between the saved fp and sp, inclusive */
+ return dummyframe->regs;
+
+ return 0;
+}
+
+/* Function: pc_in_call_dummy (pc, fp)
+ Return true if this is a dummy frame created by gdb for an inferior call */
+
+int
+generic_pc_in_call_dummy (pc, fp)
+ CORE_ADDR pc;
+ CORE_ADDR fp;
+{
+ /* if find_dummy_frame succeeds, then PC is in a call dummy */
+ return (generic_find_dummy_frame (pc, fp) != 0);
+}
+
+/* Function: read_register_dummy
+ Find a saved register from before GDB calls a function in the inferior */
+
+CORE_ADDR
+generic_read_register_dummy (pc, fp, regno)
+ CORE_ADDR pc;
+ CORE_ADDR fp;
+ int regno;
+{
+ char *dummy_regs = generic_find_dummy_frame (pc, fp);
+
+ if (dummy_regs)
+ return extract_address (&dummy_regs[REGISTER_BYTE (regno)],
+ REGISTER_RAW_SIZE(regno));
+ else
+ return 0;
+}
+
+/* Save all the registers on the dummy frame stack. Most ports save the
+ registers on the target stack. This results in lots of unnecessary memory
+ references, which are slow when debugging via a serial line. Instead, we
+ save all the registers internally, and never write them to the stack. The
+ registers get restored when the called function returns to the entry point,
+ where a breakpoint is laying in wait. */
+
+void
+generic_push_dummy_frame ()
+{
+ struct dummy_frame *dummy_frame;
+ CORE_ADDR fp = (get_current_frame ())->frame;
+
+ /* check to see if there are stale dummy frames,
+ perhaps left over from when a longjump took us out of a
+ function that was called by the debugger */
+
+ dummy_frame = dummy_frame_stack;
+ while (dummy_frame)
+ if (dummy_frame->fp INNER_THAN fp) /* stale -- destroy! */
+ {
+ dummy_frame_stack = dummy_frame->next;
+ free (dummy_frame);
+ dummy_frame = dummy_frame_stack;
+ }
+ else
+ dummy_frame = dummy_frame->next;
+
+ dummy_frame = xmalloc (sizeof (struct dummy_frame));
+ dummy_frame->pc = read_register (PC_REGNUM);
+ dummy_frame->sp = read_register (SP_REGNUM);
+ dummy_frame->fp = fp;
+ read_register_bytes (0, dummy_frame->regs, REGISTER_BYTES);
+ dummy_frame->next = dummy_frame_stack;
+ dummy_frame_stack = dummy_frame;
+}
+
+/* Function: pop_dummy_frame
+ Restore the machine state from a saved dummy stack frame. */
+
+void
+generic_pop_dummy_frame ()
+{
+ struct dummy_frame *dummy_frame = dummy_frame_stack;
+
+ /* FIXME: what if the first frame isn't the right one, eg..
+ because one call-by-hand function has done a longjmp into another one? */
+
+ if (!dummy_frame)
+ error ("Can't pop dummy frame!");
+ dummy_frame_stack = dummy_frame->next;
+ write_register_bytes (0, dummy_frame->regs, REGISTER_BYTES);
+ free (dummy_frame);
+}
+
+/* Function: frame_chain_valid
+ Returns true for a user frame or a call_function_by_hand dummy frame,
+ and false for the CRT0 start-up frame. Purpose is to terminate backtrace */
+
+int
+generic_frame_chain_valid (fp, fi)
+ CORE_ADDR fp;
+ struct frame_info *fi;
{
+ if (PC_IN_CALL_DUMMY(FRAME_SAVED_PC(fi), fp, fp))
+ return 1; /* don't prune CALL_DUMMY frames */
+ else /* fall back to default algorithm (see frame.h) */
+ return (fp != 0
+ && fi->frame INNER_THAN fp
+ && !inside_entry_file (FRAME_SAVED_PC(fi)));
}
+
+/* Function: get_saved_register
+ Find register number REGNUM relative to FRAME and put its (raw,
+ target format) contents in *RAW_BUFFER.
+
+ Set *OPTIMIZED if the variable was optimized out (and thus can't be
+ fetched). Note that this is never set to anything other than zero
+ in this implementation.
+
+ Set *LVAL to lval_memory, lval_register, or not_lval, depending on
+ whether the value was fetched from memory, from a register, or in a
+ strange and non-modifiable way (e.g. a frame pointer which was
+ calculated rather than fetched). We will use not_lval for values
+ fetched from generic dummy frames.
+
+ Set *ADDRP to the address, either in memory on as a REGISTER_BYTE
+ offset into the registers array. If the value is stored in a dummy
+ frame, set *ADDRP to zero.
+
+ To use this implementation, define a function called
+ "get_saved_register" in your target code, which simply passes all
+ of its arguments to this function.
+
+ The argument RAW_BUFFER must point to aligned memory. */
+
+void
+generic_get_saved_register (raw_buffer, optimized, addrp, frame, regnum, lval)
+ char *raw_buffer;
+ int *optimized;
+ CORE_ADDR *addrp;
+ struct frame_info *frame;
+ int regnum;
+ enum lval_type *lval;
+{
+ CORE_ADDR addr;
+ struct frame_saved_regs fsr;
+
+ if (!target_has_registers)
+ error ("No registers.");
+
+ /* Normal systems don't optimize out things with register numbers. */
+ if (optimized != NULL)
+ *optimized = 0;
+
+ if (addrp) /* default assumption: not found in memory */
+ *addrp = 0;
-END_FILE
+ /* Note: since the current frame's registers could only have been
+ saved by frames INTERIOR TO the current frame, we skip examining
+ the current frame itself: otherwise, we would be getting the
+ previous frame's registers which were saved by the current frame. */
+
+ while (frame && ((frame = frame->next) != NULL))
+ {
+ if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
+ {
+ if (lval) /* found it in a CALL_DUMMY frame */
+ *lval = not_lval;
+ if (raw_buffer)
+ memcpy (raw_buffer,
+ generic_find_dummy_frame (frame->pc, frame->frame) +
+ REGISTER_BYTE (regnum),
+ REGISTER_RAW_SIZE (regnum));
+ return;
+ }
+
+ FRAME_FIND_SAVED_REGS(frame, fsr);
+ if (fsr.regs[regnum] != 0)
+ {
+ if (lval) /* found it saved on the stack */
+ *lval = lval_memory;
+ if (regnum == SP_REGNUM)
+ {
+ if (raw_buffer) /* SP register treated specially */
+ store_address (raw_buffer, REGISTER_RAW_SIZE (regnum),
+ fsr.regs[regnum]);
+ }
+ else
+ {
+ if (addrp) /* any other register */
+ *addrp = fsr.regs[regnum];
+ if (raw_buffer)
+ read_memory (fsr.regs[regnum], raw_buffer,
+ REGISTER_RAW_SIZE (regnum));
+ }
+ return;
+ }
+ }
+
+ /* If we get thru the loop to this point, it means the register was
+ not saved in any frame. Return the actual live-register value. */
+
+ if (lval) /* found it in a live register */
+ *lval = lval_register;
+ if (addrp)
+ *addrp = REGISTER_BYTE (regnum);
+ if (raw_buffer)
+ read_register_gen (regnum, raw_buffer);
+}
+#endif /* USE_GENERIC_DUMMY_FRAMES */
+
+void
+_initialize_blockframe ()
+{
+ obstack_init (&frame_cache_obstack);
+}
projects / deliverable / binutils-gdb.git / blobdiff