/* Get info from stack frames;
convert between frames, blocks, functions and pc values.
- Copyright (C) 1986, 1987, 1988 Free Software Foundation, Inc.
+ Copyright 1986, 1987, 1988, 1989, 1991 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "defs.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 */
+
+/* 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. */
+ 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. */
+
+int
+inside_main_func (pc)
+CORE_ADDR pc;
+{
+ if (pc == 0)
+ return 1;
+ if (symfile_objfile == 0)
+ return 0;
+ 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. */
+ 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);
+}
/* Address of innermost stack frame (contents of FP register) */
static FRAME current_frame;
-struct block *block_for_pc ();
-CORE_ADDR get_pc_function_start ();
-
/*
* Cache for frame addresses already read by gdb. Valid only while
* inferior is stopped. Control variables for the frame cache should
CORE_ADDR pc;
{
struct frame_info *fci; /* Same type as FRAME */
+ char *name;
fci = (struct frame_info *)
obstack_alloc (&frame_cache_obstack,
fci->next = (struct frame_info *) 0;
fci->prev = (struct frame_info *) 0;
fci->frame = addr;
- fci->next_frame = 0; /* Since arbitrary */
fci->pc = pc;
+ find_pc_partial_function (pc, &name, (CORE_ADDR *)NULL,(CORE_ADDR *)NULL);
+ fci->signal_handler_caller = IN_SIGTRAMP (fci->pc, name);
#ifdef INIT_EXTRA_FRAME_INFO
- INIT_EXTRA_FRAME_INFO (fci);
+ INIT_EXTRA_FRAME_INFO (0, fci);
#endif
return fci;
return get_prev_frame_info (frame);
}
+/* Return the frame that FRAME calls (0 if FRAME is the innermost
+ frame). */
+
+FRAME
+get_next_frame (frame)
+ FRAME frame;
+{
+ /* We're allowed to know that FRAME and "struct frame_info *" are
+ the same */
+ return frame->next;
+}
+
/*
* Flush the entire frame cache.
*/
/* 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 = (struct frame_info *) 0; /* Invalidate cache */
}
+/* Flush the frame cache, and start a new one if necessary. */
+void
+reinit_frame_cache ()
+{
+ flush_cached_frames ();
+ if (target_has_stack)
+ {
+ set_current_frame (create_new_frame (read_fp (), read_pc ()));
+ select_frame (get_current_frame (), 0);
+ }
+ else
+ {
+ set_current_frame (0);
+ select_frame ((FRAME) 0, -1);
+ }
+}
+
/* Return a structure containing various interesting information
about a specified stack frame. */
/* How do I justify including this function? Well, the FRAME
return frame;
}
+/* 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. */
+
+int
+frameless_look_for_prologue (frame)
+ FRAME frame;
+{
+ CORE_ADDR func_start, after_prologue;
+ func_start = (get_pc_function_start (frame->pc) +
+ FUNCTION_START_OFFSET);
+ if (func_start)
+ {
+ 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 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;
+}
+
+/* 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
+
+#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. */
+ about the frame that called NEXT_FRAME. Returns NULL
+ if there is no such frame. */
struct frame_info *
get_prev_frame_info (next_frame)
FRAME next_frame;
{
- FRAME_ADDR address;
+ FRAME_ADDR address = 0;
struct frame_info *prev;
int fromleaf = 0;
-
- /* If we are within "start" right now, don't go any higher. */
- /* This truncates stack traces of things at sigtramp() though,
- because sigtramp() doesn't have a normal return PC, it has
- garbage or a small value (seen: 3) in the return PC slot.
- It's VITAL to see where the signal occurred, so punt this. */
-#if 0
- if (next_frame && next_frame->pc < first_object_file_end)
- return 0;
-#endif
+ char *name;
/* If the requested entry is in the cache, return it.
Otherwise, figure out what the address should be for the entry
if (!next_frame)
{
if (!current_frame)
- error ("No frame is currently selected.");
+ {
+ error ("You haven't set up a process's stack to examine.");
+ }
return current_frame;
}
- else
+
+ /* 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))
{
- /* If we have the prev one, return it */
- if (next_frame->prev)
- return next_frame->prev;
-
- /* There is a questionable, but probably always correct
- assumption being made here. The assumption is that if
- functions on a specific machine has a FUNCTION_START_OFFSET,
- then this is used by the function call instruction for some
- purpose. If the function call instruction has this much hair
- in it, it probably also sets up the frame pointer
- automatically (ie. we'll never have what I am calling a
- "leaf node", one which shares a frame pointer with it's
- calling function). This is true on a vax. The only other
- way to find this out would be to setup a seperate macro
- "FUNCTION_HAS_FRAME_POINTER", which would often be equivalent
- to SKIP_PROLOGUE modifying a pc value. */
-
-#if FUNCTION_START_OFFSET == 0
- if (!(next_frame->next))
- {
- /* Innermost */
- CORE_ADDR func_start, after_prologue;
-
- func_start = (get_pc_function_start (next_frame->pc) +
- FUNCTION_START_OFFSET);
- after_prologue = func_start;
- SKIP_PROLOGUE (after_prologue);
- if (after_prologue == func_start)
- {
- fromleaf = 1;
- address = next_frame->frame;
- }
- }
+ FRAMELESS_FUNCTION_INVOCATION (next_frame, fromleaf);
+ if (fromleaf)
+ address = next_frame->frame;
+ }
#endif
- if (!fromleaf)
- {
- /* 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. */
- address = FRAME_CHAIN (next_frame);
- if (!FRAME_CHAIN_VALID (address, next_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. */
- address = FRAME_CHAIN_COMBINE (address, next_frame);
- }
+ 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,
prev->next = next_frame;
prev->prev = (struct frame_info *) 0;
prev->frame = address;
- prev->next_frame = prev->next ? prev->next->frame : 0;
+ 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.
+
+ To answer the question, yes the sparc needs INIT_FRAME_PC after
+ INIT_EXTRA_FRAME_INFO. Suggested 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.
+ 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. */
+
+#ifdef INIT_FRAME_PC_FIRST
+ INIT_FRAME_PC_FIRST (fromleaf, prev);
+#endif
#ifdef INIT_EXTRA_FRAME_INFO
- INIT_EXTRA_FRAME_INFO(prev);
+ 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 it's value
- (see m-sparc.h). We want the pc saved in the inferior frame. */
- prev->pc = (fromleaf ? SAVED_PC_AFTER_CALL (next_frame) :
- next_frame ? FRAME_SAVED_PC (next_frame) : read_pc ());
+ (see tm-sparc.h). We want the pc saved in the inferior frame. */
+ INIT_FRAME_PC(fromleaf, prev);
+
+ 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;
}
return fi->pc;
}
+#if defined (FRAME_FIND_SAVED_REGS)
/* Find the addresses in which registers are saved in FRAME. */
void
struct frame_info *frame_info_addr;
struct frame_saved_regs *saved_regs_addr;
{
-#if 1
FRAME_FIND_SAVED_REGS (frame_info_addr, *saved_regs_addr);
-#else
- {
- register int regnum;
- register int regmask;
- register CORE_ADDR next_addr;
- register CORE_ADDR pc;
- int nextinsn;
- bzero (&*saved_regs_addr, sizeof *saved_regs_addr);
- if ((frame_info_addr)->pc >= ((frame_info_addr)->frame
- - CALL_DUMMY_LENGTH - FP_REGNUM*4 - 8*12 - 4)
- && (frame_info_addr)->pc <= (frame_info_addr)->frame)
- {
- next_addr = (frame_info_addr)->frame;
- pc = (frame_info_addr)->frame - CALL_DUMMY_LENGTH - FP_REGNUM * 4 - 8*12 - 4;
- }
- else
- {
- pc = get_pc_function_start ((frame_info_addr)->pc);
- /* Verify we have a link a6 instruction next;
- if not we lose. If we win, find the address above the saved
- regs using the amount of storage from the link instruction. */
- if (044016 == read_memory_integer (pc, 2))
- {
- next_addr = (frame_info_addr)->frame + read_memory_integer (pc += 2, 4);
- pc += 4;
- }
- else if (047126 == read_memory_integer (pc, 2))
- {
- next_addr = (frame_info_addr)->frame + read_memory_integer (pc += 2, 2);
- pc+=2;
- }
- else goto lose;
-
- /* If have an addal #-n, sp next, adjust next_addr. */
- if ((0177777 & read_memory_integer (pc, 2)) == 0157774)
- {
- next_addr += read_memory_integer (pc += 2, 4);
- pc += 4;
- }
- }
- /* next should be a moveml to (sp) or -(sp) or a movl r,-(sp) */
- regmask = read_memory_integer (pc + 2, 2);
-
- /* But before that can come an fmovem. Check for it. */
- nextinsn = 0xffff & read_memory_integer (pc, 2);
- if (0xf227 == nextinsn
- && (regmask & 0xff00) == 0xe000)
- {
- pc += 4; /* Regmask's low bit is for register fp7, the first pushed */
- for (regnum = FP0_REGNUM + 7;
- regnum >= FP0_REGNUM;
- regnum--, regmask >>= 1)
- if (regmask & 1)
- (*saved_regs_addr).regs[regnum] = (next_addr -= 12);
- regmask = read_memory_integer (pc + 2, 2);
- }
- if (0044327 == read_memory_integer (pc, 2))
- {
- pc += 4; /* Regmask's low bit is for register 0, the first written */
- for (regnum = 0; regnum < 16; regnum++, regmask >>= 1)
- if (regmask & 1)
- (*saved_regs_addr).regs[regnum] = (next_addr += 4) - 4;
- }
- else if (0044347 == read_memory_integer (pc, 2))
- { pc += 4; /* Regmask's low bit is for register 15, the first pushed */
- for (regnum = 15; regnum >= 0; regnum--, regmask >>= 1)
- if (regmask & 1)
- (*saved_regs_addr).regs[regnum] = (next_addr -= 4); }
- else if (0x2f00 == (0xfff0 & read_memory_integer (pc, 2)))
- { regnum = 0xf & read_memory_integer (pc, 2); pc += 2;
- (*saved_regs_addr).regs[regnum] = (next_addr -= 4); }
- /* fmovemx to index of sp may follow. */
- regmask = read_memory_integer (pc + 2, 2);
- nextinsn = 0xffff & read_memory_integer (pc, 2);
- if (0xf236 == nextinsn
- && (regmask & 0xff00) == 0xf000)
- {
- pc += 10; /* Regmask's low bit is for register fp0, the first written */
- for (regnum = FP0_REGNUM + 7;
- regnum >= FP0_REGNUM;
- regnum--, regmask >>= 1)
- if (regmask & 1)
- (*saved_regs_addr).regs[regnum] = (next_addr += 12) - 12;
- regmask = read_memory_integer (pc + 2, 2);
- }
- /* clrw -(sp); movw ccr,-(sp) may follow. */
- if (0x426742e7 == read_memory_integer (pc, 4))
- (*saved_regs_addr).regs[PS_REGNUM] = (next_addr -= 4);
- lose: ;
- (*saved_regs_addr).regs[SP_REGNUM] = (frame_info_addr)->frame + 8;
- (*saved_regs_addr).regs[FP_REGNUM] = (frame_info_addr)->frame;
- (*saved_regs_addr).regs[PC_REGNUM] = (frame_info_addr)->frame + 4;
- }
-#endif
}
+#endif
/* Return the innermost lexical block in execution
in a specified stack frame. The frame address is assumed valid. */
FRAME frame;
{
struct frame_info *fi;
+ CORE_ADDR pc;
fi = get_frame_info (frame);
- return block_for_pc (fi->pc);
+
+ pc = fi->pc;
+ if (fi->next != 0)
+ /* We are not in the innermost frame. 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 fi->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 || (symbol = block_function (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);
}
- bl = SYMBOL_BLOCK_VALUE (symbol);
- return BLOCK_START (bl);
+ else
+ {
+ fstart = 0;
+ }
+ return (fstart);
}
/* Return the symbol for the function executing in frame FRAME. */
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. */
-extern struct symtab *psymtab_to_symtab ();
-
-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;
register struct symtab *s;
- register struct partial_symtab *ps;
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;
- }
-
- if (s == 0)
- for (ps = partial_symtab_list; ps; ps = ps->next)
- {
- if (ps->textlow <= pc
- && ps->texthigh > pc)
- {
- s = psymtab_to_symtab (ps);
- bl = BLOCKVECTOR (s);
- b = BLOCKVECTOR_BLOCK (bl, 0);
- 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)
- register CORE_ADDR pc;
+find_pc_partial_function (pc, name, address, endaddr)
+ CORE_ADDR pc;
+ char **name;
+ CORE_ADDR *address;
+ CORE_ADDR *endaddr;
{
- register int lo = 0;
- register int hi = misc_function_count-1;
- register int new;
- register int distance;
-
- /* Note that the last thing in the vector is always _etext. */
-
- /* Above statement is not *always* true - fix for case where there are */
- /* no misc functions at all (ie no symbol table has been read). */
- if (hi < 0) return -1; /* no misc functions recorded */
-
- /* trivial reject range test */
- if (pc < misc_function_vector[0].address ||
- pc > misc_function_vector[hi].address)
- return -1;
-
- do {
- new = (lo + hi) >> 1;
- distance = misc_function_vector[new].address - pc;
- if (distance == 0)
- return new; /* an exact match */
- else if (distance > 0)
- hi = new;
- else
- lo = new;
- } while (hi-lo != 1);
-
- /* if here, we had no exact match, so return the lower choice */
- return lo;
+ struct partial_symtab *pst;
+ struct symbol *f;
+ struct minimal_symbol *msymbol;
+ struct partial_symbol *psb;
+
+ 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;
+ cache_pc_function_high = SIGTRAMP_END;
+ cache_pc_function_name = "<sigtramp>";
+
+ goto return_cached_value;
+ }
+#endif
+
+ msymbol = lookup_minimal_symbol_by_pc (pc);
+ pst = find_pc_psymtab (pc);
+ if (pst)
+ {
+ /* Need to read the symbols to get a good value for the end address. */
+ if (endaddr != NULL && !pst->readin)
+ 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;
+ }
+ }
+ }
+
+ /* 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;
+ }
+
+ /* I believe the purpose of this check is to make sure that anything
+ beyond the end of the text segment does not appear as part of the
+ last function of the text segment. It assumes that there is something
+ other than a mst_text symbol after the text segment. It is broken in
+ various cases, so anything relying on this behavior (there might be
+ some places) should be using find_pc_section or some such instead. */
+ if (msymbol -> type == mst_text)
+ cache_pc_function_low = SYMBOL_VALUE_ADDRESS (msymbol);
+ else
+ /* It is a transfer table for Sun shared libraries. */
+ cache_pc_function_low = pc - FUNCTION_START_OFFSET;
+ cache_pc_function_name = SYMBOL_NAME (msymbol);
+
+ if (SYMBOL_NAME (msymbol + 1) != NULL)
+ /* This might be part of a different segment, which might be a bad
+ idea. Perhaps we should be using the smaller of this address or the
+ endaddr from find_pc_section. */
+ 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. */
+ struct obj_section *sec;
+
+ sec = find_pc_section (pc);
+ if (sec == NULL)
+ {
+ /* Don't know if this can happen but if it does, then just say
+ that the function is 1 byte long. */
+ cache_pc_function_high = cache_pc_function_low + 1;
+ }
+ else
+ 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
block_innermost_frame (block)
{
struct frame_info *fi;
register FRAME frame;
- register CORE_ADDR start = BLOCK_START (block);
- register CORE_ADDR end = BLOCK_END (block);
+ register CORE_ADDR start;
+ register CORE_ADDR end;
+
+ if (block == NULL)
+ return NULL;
+
+ start = BLOCK_START (block);
+ end = BLOCK_END (block);
frame = 0;
while (1)
}
}
+#ifdef SIGCONTEXT_PC_OFFSET
+/* Get saved user PC for sigtramp from sigcontext for BSD style sigtramp. */
+
+CORE_ADDR
+sigtramp_saved_pc (frame)
+ FRAME 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 */
+
void
_initialize_blockframe ()
{