| /* Get info from stack frames; |
| convert between frames, blocks, functions and pc values. |
| Copyright 1986, 87, 88, 89, 91, 94, 95, 96, 97, 1998 |
| Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| 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. |
| |
| 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 "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" |
| |
| /* Prototypes for exported functions. */ |
| |
| void _initialize_blockframe (void); |
| |
| /* A default FRAME_CHAIN_VALID, in the form that is suitable for most |
| targets. If FRAME_CHAIN_VALID returns zero it means that the given |
| frame is the outermost one and has no caller. */ |
| |
| int |
| file_frame_chain_valid (chain, thisframe) |
| CORE_ADDR chain; |
| struct frame_info *thisframe; |
| { |
| return ((chain) != 0 |
| && !inside_entry_file (FRAME_SAVED_PC (thisframe))); |
| } |
| |
| /* Use the alternate method of avoiding running up off the end of the |
| frame chain or following frames back into the startup code. See |
| the comments in objfiles.h. */ |
| |
| int |
| func_frame_chain_valid (chain, thisframe) |
| CORE_ADDR chain; |
| struct frame_info *thisframe; |
| { |
| return ((chain) != 0 |
| && !inside_main_func ((thisframe)->pc) |
| && !inside_entry_func ((thisframe)->pc)); |
| } |
| |
| /* A very simple method of determining a valid frame */ |
| |
| int |
| nonnull_frame_chain_valid (chain, thisframe) |
| CORE_ADDR chain; |
| struct frame_info *thisframe; |
| { |
| return ((chain) != 0); |
| } |
| |
| /* 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; |
| } |
| 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. |
| |
| Typically called from FRAME_CHAIN_VALID. |
| |
| 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; |
| |
| /* 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. */ |
| |
| if (symfile_objfile->ei.main_func_lowpc == INVALID_ENTRY_LOWPC && |
| symfile_objfile->ei.main_func_highpc == INVALID_ENTRY_HIGHPC) |
| { |
| struct symbol *mainsym; |
| |
| 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; |
| } |
| 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. */ |
| |
| static struct obstack frame_cache_obstack; |
| |
| void * |
| frame_obstack_alloc (size) |
| unsigned long size; |
| { |
| return obstack_alloc (&frame_cache_obstack, size); |
| } |
| |
| void |
| frame_saved_regs_zalloc (fi) |
| struct frame_info *fi; |
| { |
| fi->saved_regs = (CORE_ADDR *) |
| frame_obstack_alloc (SIZEOF_FRAME_SAVED_REGS); |
| memset (fi->saved_regs, 0, SIZEOF_FRAME_SAVED_REGS); |
| } |
| |
| |
| /* Return the innermost (currently executing) stack frame. */ |
| |
| struct frame_info * |
| get_current_frame () |
| { |
| 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) |
| struct frame_info *frame; |
| { |
| current_frame = frame; |
| } |
| |
| /* 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->saved_regs = NULL; |
| 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 FRAME calls (NULL if FRAME is the innermost |
| frame). */ |
| |
| struct frame_info * |
| get_next_frame (frame) |
| struct frame_info *frame; |
| { |
| return frame->next; |
| } |
| |
| /* Flush the entire frame cache. */ |
| |
| 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) |
| { |
| select_frame (get_current_frame (), 0); |
| } |
| } |
| |
| /* 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) |
| 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; |
| /* This is faster, since only care whether there *is* a |
| prologue, not how long it is. */ |
| return PROLOGUE_FRAMELESS_P (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; |
| } |
| |
| /* 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. Returns NULL |
| if there is no such frame. */ |
| |
| struct frame_info * |
| get_prev_frame (next_frame) |
| struct frame_info *next_frame; |
| { |
| CORE_ADDR address = 0; |
| struct frame_info *prev; |
| int fromleaf = 0; |
| char *name; |
| |
| /* 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) |
| { |
| #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. */ |
| |
| /* 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)) |
| { |
| fromleaf = FRAMELESS_FUNCTION_INVOCATION (next_frame); |
| if (fromleaf) |
| address = FRAME_FP (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, |
| sizeof (struct frame_info)); |
| |
| prev->saved_regs = NULL; |
| 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) |
| { |
| if (prev->frame == next_frame->frame |
| && prev->pc == next_frame->pc) |
| { |
| next_frame->prev = NULL; |
| obstack_free (&frame_cache_obstack, prev); |
| return NULL; |
| } |
| } |
| |
| 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) |
| struct frame_info *frame; |
| { |
| return frame->pc; |
| } |
| |
| |
| #ifdef FRAME_FIND_SAVED_REGS |
| /* XXX - deprecated. This is a compatibility function for targets |
| that do not yet implement FRAME_INIT_SAVED_REGS. */ |
| /* Find the addresses in which registers are saved in FRAME. */ |
| |
| void |
| get_frame_saved_regs (frame, saved_regs_addr) |
| struct frame_info *frame; |
| struct frame_saved_regs *saved_regs_addr; |
| { |
| if (frame->saved_regs == NULL) |
| { |
| frame->saved_regs = (CORE_ADDR *) |
| frame_obstack_alloc (SIZEOF_FRAME_SAVED_REGS); |
| } |
| if (saved_regs_addr == NULL) |
| { |
| struct frame_saved_regs saved_regs; |
| FRAME_FIND_SAVED_REGS (frame, saved_regs); |
| memcpy (frame->saved_regs, &saved_regs, SIZEOF_FRAME_SAVED_REGS); |
| } |
| else |
| { |
| FRAME_FIND_SAVED_REGS (frame, *saved_regs_addr); |
| memcpy (frame->saved_regs, saved_regs_addr, SIZEOF_FRAME_SAVED_REGS); |
| } |
| } |
| #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) |
| struct frame_info *frame; |
| { |
| CORE_ADDR 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_current_block () |
| { |
| return block_for_pc (read_pc ()); |
| } |
| |
| CORE_ADDR |
| get_pc_function_start (pc) |
| CORE_ADDR pc; |
| { |
| register struct block *bl; |
| register struct symbol *symbol; |
| register struct minimal_symbol *msymbol; |
| CORE_ADDR fstart; |
| |
| if ((bl = block_for_pc (pc)) != NULL && |
| (symbol = block_function (bl)) != NULL) |
| { |
| 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; |
| } |
| return (fstart); |
| } |
| |
| /* Return the symbol for the function executing in frame FRAME. */ |
| |
| struct symbol * |
| get_frame_function (frame) |
| struct frame_info *frame; |
| { |
| register struct block *bl = get_frame_block (frame); |
| if (bl == 0) |
| return 0; |
| return block_function (bl); |
| } |
| |
| |
| /* Return the blockvector immediately containing the innermost lexical block |
| containing the specified pc value and section, 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 blockvector * |
| blockvector_for_pc_sect (pc, section, pindex, symtab) |
| register CORE_ADDR pc; |
| struct sec *section; |
| int *pindex; |
| struct symtab *symtab; |
| |
| { |
| register struct block *b; |
| register int bot, top, half; |
| struct blockvector *bl; |
| |
| if (symtab == 0) /* if no symtab specified by caller */ |
| { |
| /* First search all symtabs for one whose file contains our pc */ |
| if ((symtab = find_pc_sect_symtab (pc, section)) == 0) |
| return 0; |
| } |
| |
| bl = BLOCKVECTOR (symtab); |
| 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. */ |
| |
| bot = 0; |
| top = BLOCKVECTOR_NBLOCKS (bl); |
| |
| while (top - bot > 1) |
| { |
| half = (top - bot + 1) >> 1; |
| b = BLOCKVECTOR_BLOCK (bl, bot + half); |
| if (BLOCK_START (b) <= pc) |
| bot += half; |
| else |
| top = bot + half; |
| } |
| |
| /* Now search backward for a block that ends after PC. */ |
| |
| while (bot >= 0) |
| { |
| b = BLOCKVECTOR_BLOCK (bl, bot); |
| if (BLOCK_END (b) > pc) |
| { |
| if (pindex) |
| *pindex = bot; |
| return bl; |
| } |
| bot--; |
| } |
| return 0; |
| } |
| |
| /* Return the blockvector immediately containing the innermost lexical block |
| containing the specified pc value, or 0 if there is none. |
| Backward compatibility, no section. */ |
| |
| struct blockvector * |
| blockvector_for_pc (pc, pindex) |
| register CORE_ADDR pc; |
| int *pindex; |
| { |
| return blockvector_for_pc_sect (pc, find_pc_mapped_section (pc), |
| pindex, NULL); |
| } |
| |
| /* Return the innermost lexical block containing the specified pc value |
| in the specified section, or 0 if there is none. */ |
| |
| struct block * |
| block_for_pc_sect (pc, section) |
| register CORE_ADDR pc; |
| struct sec *section; |
| { |
| register struct blockvector *bl; |
| int index; |
| |
| bl = blockvector_for_pc_sect (pc, section, &index, NULL); |
| if (bl) |
| return BLOCKVECTOR_BLOCK (bl, index); |
| return 0; |
| } |
| |
| /* Return the innermost lexical block containing the specified pc value, |
| or 0 if there is none. Backward compatibility, no section. */ |
| |
| struct block * |
| block_for_pc (pc) |
| register CORE_ADDR pc; |
| { |
| return block_for_pc_sect (pc, find_pc_mapped_section (pc)); |
| } |
| |
| /* Return the function containing pc value PC in section SECTION. |
| Returns 0 if function is not known. */ |
| |
| struct symbol * |
| find_pc_sect_function (pc, section) |
| CORE_ADDR pc; |
| struct sec *section; |
| { |
| register struct block *b = block_for_pc_sect (pc, section); |
| if (b == 0) |
| return 0; |
| return block_function (b); |
| } |
| |
| /* Return the function containing pc value PC. |
| Returns 0 if function is not known. Backward compatibility, no section */ |
| |
| struct symbol * |
| find_pc_function (pc) |
| CORE_ADDR pc; |
| { |
| return find_pc_sect_function (pc, find_pc_mapped_section (pc)); |
| } |
| |
| /* 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; |
| static struct sec *cache_pc_function_section = NULL; |
| |
| /* 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; |
| cache_pc_function_section = NULL; |
| } |
| |
| /* Finds the "function" (text symbol) that is smaller than PC but |
| greatest of all of the potential text symbols in SECTION. 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_sect_partial_function (pc, section, name, address, endaddr) |
| CORE_ADDR pc; |
| asection *section; |
| char **name; |
| CORE_ADDR *address; |
| CORE_ADDR *endaddr; |
| { |
| struct partial_symtab *pst; |
| struct symbol *f; |
| struct minimal_symbol *msymbol; |
| struct partial_symbol *psb; |
| struct obj_section *osect; |
| int i; |
| CORE_ADDR mapped_pc; |
| |
| mapped_pc = overlay_mapped_address (pc, section); |
| |
| if (mapped_pc >= cache_pc_function_low && |
| mapped_pc < cache_pc_function_high && |
| section == cache_pc_function_section) |
| 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 (mapped_pc, (char *) NULL)) |
| { |
| cache_pc_function_low = SIGTRAMP_START (mapped_pc); |
| cache_pc_function_high = SIGTRAMP_END (mapped_pc); |
| cache_pc_function_name = "<sigtramp>"; |
| cache_pc_function_section = section; |
| goto return_cached_value; |
| } |
| #endif |
| |
| msymbol = lookup_minimal_symbol_by_pc_section (mapped_pc, section); |
| pst = find_pc_sect_psymtab (mapped_pc, section); |
| if (pst) |
| { |
| /* 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_sect_function (mapped_pc, section); |
| 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); |
| cache_pc_function_section = section; |
| 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_sect_psymbol (pst, mapped_pc, section); |
| |
| 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. */ |
| |
| osect = find_pc_sect_section (mapped_pc, section); |
| |
| if (!osect) |
| 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; |
| } |
| |
| cache_pc_function_low = SYMBOL_VALUE_ADDRESS (msymbol); |
| cache_pc_function_name = SYMBOL_NAME (msymbol); |
| cache_pc_function_section = section; |
| |
| /* Use the lesser of the next minimal symbol in the same section, or |
| the end of the section, as the end of the function. */ |
| |
| /* Step over other symbols at this same address, and symbols in |
| other sections, to find the next symbol in this section with |
| a different address. */ |
| |
| for (i = 1; SYMBOL_NAME (msymbol + i) != NULL; i++) |
| { |
| if (SYMBOL_VALUE_ADDRESS (msymbol + i) != SYMBOL_VALUE_ADDRESS (msymbol) |
| && SYMBOL_BFD_SECTION (msymbol + i) == SYMBOL_BFD_SECTION (msymbol)) |
| break; |
| } |
| |
| if (SYMBOL_NAME (msymbol + i) != NULL |
| && SYMBOL_VALUE_ADDRESS (msymbol + i) < osect->endaddr) |
| cache_pc_function_high = SYMBOL_VALUE_ADDRESS (msymbol + i); |
| 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 = osect->endaddr; |
| |
| return_cached_value: |
| |
| if (address) |
| { |
| if (pc_in_unmapped_range (pc, section)) |
| *address = overlay_unmapped_address (cache_pc_function_low, section); |
| else |
| *address = cache_pc_function_low; |
| } |
| |
| if (name) |
| *name = cache_pc_function_name; |
| |
| if (endaddr) |
| { |
| if (pc_in_unmapped_range (pc, section)) |
| { |
| /* Because the high address is actually beyond the end of |
| the function (and therefore possibly beyond the end of |
| the overlay), we must actually convert (high - 1) |
| and then add one to that. */ |
| |
| *endaddr = 1 + overlay_unmapped_address (cache_pc_function_high - 1, |
| section); |
| } |
| else |
| *endaddr = cache_pc_function_high; |
| } |
| |
| return 1; |
| } |
| |
| /* Backward compatibility, no section argument */ |
| |
| int |
| find_pc_partial_function (pc, name, address, endaddr) |
| CORE_ADDR pc; |
| char **name; |
| CORE_ADDR *address; |
| CORE_ADDR *endaddr; |
| { |
| asection *section; |
| |
| section = find_pc_overlay (pc); |
| return find_pc_sect_partial_function (pc, section, name, address, endaddr); |
| } |
| |
| /* Return the innermost stack frame executing inside of BLOCK, |
| or NULL if there is no such frame. If BLOCK is NULL, just return NULL. */ |
| |
| struct frame_info * |
| block_innermost_frame (block) |
| struct block *block; |
| { |
| struct frame_info *frame; |
| register CORE_ADDR start; |
| register CORE_ADDR end; |
| |
| if (block == NULL) |
| return NULL; |
| |
| start = BLOCK_START (block); |
| end = BLOCK_END (block); |
| |
| frame = NULL; |
| while (1) |
| { |
| frame = get_prev_frame (frame); |
| if (frame == NULL) |
| return NULL; |
| if (frame->pc >= start && frame->pc < end) |
| return frame; |
| } |
| } |
| |
| /* 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 */ |
| |
| |
| /* Are we in a call dummy? The code below which allows DECR_PC_AFTER_BREAK |
| below is for infrun.c, which may give the macro a pc without that |
| subtracted out. */ |
| |
| extern CORE_ADDR text_end; |
| |
| int |
| pc_in_call_dummy_before_text_end (pc, sp, frame_address) |
| CORE_ADDR pc; |
| CORE_ADDR sp; |
| CORE_ADDR frame_address; |
| { |
| return ((pc) >= text_end - CALL_DUMMY_LENGTH |
| && (pc) <= text_end + DECR_PC_AFTER_BREAK); |
| } |
| |
| int |
| pc_in_call_dummy_after_text_end (pc, sp, frame_address) |
| CORE_ADDR pc; |
| CORE_ADDR sp; |
| CORE_ADDR frame_address; |
| { |
| return ((pc) >= text_end |
| && (pc) <= text_end + CALL_DUMMY_LENGTH + DECR_PC_AFTER_BREAK); |
| } |
| |
| /* Is the PC in a call dummy? SP and FRAME_ADDRESS are the bottom and |
| top of the stack frame which we are checking, where "bottom" and |
| "top" refer to some section of memory which contains the code for |
| the call dummy. Calls to this macro assume that the contents of |
| SP_REGNUM and FP_REGNUM (or the saved values thereof), respectively, |
| are the things to pass. |
| |
| This won't work on the 29k, where SP_REGNUM and FP_REGNUM don't |
| have that meaning, but the 29k doesn't use ON_STACK. This could be |
| fixed by generalizing this scheme, perhaps by passing in a frame |
| and adding a few fields, at least on machines which need them for |
| PC_IN_CALL_DUMMY. |
| |
| Something simpler, like checking for the stack segment, doesn't work, |
| since various programs (threads implementations, gcc nested function |
| stubs, etc) may either allocate stack frames in another segment, or |
| allocate other kinds of code on the stack. */ |
| |
| int |
| pc_in_call_dummy_on_stack (pc, sp, frame_address) |
| CORE_ADDR pc; |
| CORE_ADDR sp; |
| CORE_ADDR frame_address; |
| { |
| return (INNER_THAN ((sp), (pc)) |
| && (frame_address != 0) |
| && INNER_THAN ((pc), (frame_address))); |
| } |
| |
| int |
| pc_in_call_dummy_at_entry_point (pc, sp, frame_address) |
| CORE_ADDR pc; |
| CORE_ADDR sp; |
| CORE_ADDR frame_address; |
| { |
| return ((pc) >= CALL_DUMMY_ADDRESS () |
| && (pc) <= (CALL_DUMMY_ADDRESS () + DECR_PC_AFTER_BREAK)); |
| } |
| |
| |
| /* |
| * 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. Also FRAME_CHAIN_VALID as |
| * generic_{file,func}_frame_chain_valid and FIX_CALL_DUMMY as |
| * generic_fix_call_dummy. */ |
| |
| /* Dummy frame. This saves the processor state just prior to setting |
| up the inferior function call. Older targets save the registers |
| on the target stack (but that really slows down function calls). */ |
| |
| struct dummy_frame |
| { |
| struct dummy_frame *next; |
| |
| CORE_ADDR pc; |
| CORE_ADDR fp; |
| CORE_ADDR sp; |
| CORE_ADDR top; |
| char *registers; |
| }; |
| |
| 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 |
| || fp == dummyframe->top) |
| /* The frame in question lies between the saved fp and sp, inclusive */ |
| return dummyframe->registers; |
| |
| 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, sp, fp) |
| CORE_ADDR pc; |
| CORE_ADDR sp; |
| CORE_ADDR fp; |
| { |
| /* if find_dummy_frame succeeds, then PC is in a call dummy */ |
| /* Note: SP and not FP is passed on. */ |
| return (generic_find_dummy_frame (pc, sp) != 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 (INNER_THAN (dummy_frame->fp, fp)) /* stale -- destroy! */ |
| { |
| dummy_frame_stack = dummy_frame->next; |
| free (dummy_frame->registers); |
| free (dummy_frame); |
| dummy_frame = dummy_frame_stack; |
| } |
| else |
| dummy_frame = dummy_frame->next; |
| |
| dummy_frame = xmalloc (sizeof (struct dummy_frame)); |
| dummy_frame->registers = xmalloc (REGISTER_BYTES); |
| |
| dummy_frame->pc = read_pc (); |
| dummy_frame->sp = read_sp (); |
| dummy_frame->top = dummy_frame->sp; |
| dummy_frame->fp = fp; |
| read_register_bytes (0, dummy_frame->registers, REGISTER_BYTES); |
| dummy_frame->next = dummy_frame_stack; |
| dummy_frame_stack = dummy_frame; |
| } |
| |
| void |
| generic_save_dummy_frame_tos (sp) |
| CORE_ADDR sp; |
| { |
| dummy_frame_stack->top = sp; |
| } |
| |
| /* Restore the machine state from either the saved dummy stack or a |
| real stack frame. */ |
| |
| void |
| generic_pop_current_frame (void (*popper) (struct frame_info * frame)) |
| { |
| struct frame_info *frame = get_current_frame (); |
| |
| if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame)) |
| generic_pop_dummy_frame (); |
| else |
| (*popper) (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->registers, REGISTER_BYTES); |
| flush_cached_frames (); |
| |
| free (dummy_frame->registers); |
| 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_file_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 |
| && (INNER_THAN (fi->frame, fp) || fi->frame == fp) |
| && !inside_entry_file (FRAME_SAVED_PC (fi))); |
| } |
| |
| int |
| generic_func_frame_chain_valid (fp, fi) |
| CORE_ADDR fp; |
| struct frame_info *fi; |
| { |
| if (PC_IN_CALL_DUMMY ((fi)->pc, fp, fp)) |
| return 1; /* don't prune CALL_DUMMY frames */ |
| else /* fall back to default algorithm (see frame.h) */ |
| return (fp != 0 |
| && (INNER_THAN (fi->frame, fp) || fi->frame == fp) |
| && !inside_main_func ((fi)->pc) |
| && !inside_entry_func ((fi)->pc)); |
| } |
| |
| /* Function: fix_call_dummy |
| Stub function. Generic dumy frames typically do not need to fix |
| the frame being created */ |
| |
| void |
| generic_fix_call_dummy (dummy, pc, fun, nargs, args, type, gcc_p) |
| char *dummy; |
| CORE_ADDR pc; |
| CORE_ADDR fun; |
| int nargs; |
| struct value **args; |
| struct type *type; |
| int gcc_p; |
| { |
| return; |
| } |
| |
| /* 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; |
| { |
| 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; |
| |
| /* 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_INIT_SAVED_REGS (frame); |
| if (frame->saved_regs != NULL |
| && frame->saved_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), |
| frame->saved_regs[regnum]); |
| } |
| else |
| { |
| if (addrp) /* any other register */ |
| *addrp = frame->saved_regs[regnum]; |
| if (raw_buffer) |
| read_memory (frame->saved_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); |
| } |
| |
| void |
| _initialize_blockframe (void) |
| { |
| obstack_init (&frame_cache_obstack); |
| } |