/* Get info from stack frames; convert between frames, blocks, functions and pc values. Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 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 "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" #include "regcache.h" #include "gdb_assert.h" #include "dummy-frame.h" #include "command.h" #include "gdbcmd.h" #include "block.h" /* Prototypes for exported functions. */ void _initialize_blockframe (void); /* APPLE LOCAL: Test whether PC is in the range of addresses that corresponds to the "main" function. NB: This function was originally here as inside_main_func(). In the FSF sources it moved to frame.c and takes a frame pointer. We need a variant that works on an address for the -stack-list-frames-lite routines, so I resurrected the old version. jmolenda/2006-03-15 */ int addr_inside_main_func (CORE_ADDR pc) { struct minimal_symbol *msymbol; if (symfile_objfile == 0) return 0; /* APPLE LOCAL begin don't recompute start/end of main */ /* If we've already found the start/end addrs of main, don't recompute them. This will probably be fixed in the FSF sources soon too, in which case this change can be dropped. jmolenda/2004-04-28 */ if (symfile_objfile->ei.main_func_lowpc != INVALID_ENTRY_LOWPC && symfile_objfile->ei.main_func_highpc != INVALID_ENTRY_LOWPC) return (symfile_objfile->ei.main_func_lowpc <= pc && symfile_objfile->ei.main_func_highpc > pc); /* APPLE LOCAL end don't recompute start/end of main */ /* APPLE LOCAL begin don't restrict lookup_minimal_symbol's object file */ /* Don't restrict lookup_minimal_symbol's object file to symfile_objfile -- this will fail for ZeroLink apps where symfile_objfile is just the ZL launcher stub. */ msymbol = lookup_minimal_symbol (main_name (), NULL, NULL); /* APPLE LOCAL end don't restrict lookup_minimal_symbol's object file */ /* If the address range hasn't been set up at symbol reading time, set it up now. */ if (msymbol != NULL && symfile_objfile->ei.main_func_lowpc == INVALID_ENTRY_LOWPC && symfile_objfile->ei.main_func_highpc == INVALID_ENTRY_HIGHPC) { /* brobecker/2003-10-10: We used to rely on lookup_symbol() to search the symbol associated to the "main" function. Unfortunately, lookup_symbol() uses the current-language la_lookup_symbol_nonlocal function to do the global symbol search. Depending on the language, this can introduce certain side-effects, because certain languages, for instance Ada, may find more than one match. Therefore we prefer to search the "main" function symbol using its address rather than its name. */ struct symbol *mainsym = find_pc_function (SYMBOL_VALUE_ADDRESS (msymbol)); if (mainsym && SYMBOL_CLASS (mainsym) == LOC_BLOCK) { /* APPLE LOCAL begin address ranges */ struct block *bl = SYMBOL_BLOCK_VALUE (mainsym); if (BLOCK_RANGES (bl)) { int last = BLOCK_RANGES (bl)->nelts - 1; symfile_objfile->ei.main_func_lowpc = BLOCK_LOWEST_PC (bl); symfile_objfile->ei.main_func_highpc = BLOCK_HIGHEST_PC (bl); } else { symfile_objfile->ei.main_func_lowpc = BLOCK_START (SYMBOL_BLOCK_VALUE (mainsym)); symfile_objfile->ei.main_func_highpc = BLOCK_END (SYMBOL_BLOCK_VALUE (mainsym)); } /* APPLE LOCAL end address ranges */ } } /* Not in the normal symbol tables, see if "main" is in the partial symbol table. If it's not, then give up. */ if (msymbol != NULL && MSYMBOL_TYPE (msymbol) == mst_text) { CORE_ADDR maddr = SYMBOL_VALUE_ADDRESS (msymbol); asection *msect = SYMBOL_BFD_SECTION (msymbol); struct obj_section *osect = find_pc_sect_section (maddr, msect); if (osect != NULL) { int i; /* 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_LINKAGE_NAME (msymbol + i) != NULL; i++) { if (SYMBOL_VALUE_ADDRESS (msymbol + i) != maddr && SYMBOL_BFD_SECTION (msymbol + i) == msect) break; } symfile_objfile->ei.main_func_lowpc = maddr; /* Use the lesser of the next minimal symbol in the same section, or the end of the section, as the end of the function. */ if (SYMBOL_LINKAGE_NAME (msymbol + i) != NULL && SYMBOL_VALUE_ADDRESS (msymbol + i) < osect->endaddr) symfile_objfile->ei.main_func_highpc = 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. */ symfile_objfile->ei.main_func_highpc = osect->endaddr; } } return (symfile_objfile->ei.main_func_lowpc <= pc && symfile_objfile->ei.main_func_highpc > pc); } /* Return the innermost lexical block in execution in a specified stack frame. The frame address is assumed valid. If ADDR_IN_BLOCK is non-zero, set *ADDR_IN_BLOCK to the exact code address we used to choose the block. We use this to find a source line, to decide which macro definitions are in scope. The value returned in *ADDR_IN_BLOCK isn't necessarily the frame's PC, and may not really be a valid PC at all. For example, in the caller of a function declared to never return, the code at the return address will never be reached, so the call instruction may be the very last instruction in the block. So the address we use to choose the block is actually one byte before the return address --- hopefully pointing us at the call instruction, or its delay slot instruction. */ struct block * get_frame_block (struct frame_info *frame, CORE_ADDR *addr_in_block) { const CORE_ADDR pc = get_frame_address_in_block (frame); if (addr_in_block) *addr_in_block = pc; return block_for_pc (pc); } CORE_ADDR get_pc_function_start (CORE_ADDR pc) { struct block *bl; struct minimal_symbol *msymbol; bl = block_for_pc (pc); if (bl) { struct symbol *symbol = block_function (bl); if (symbol) { bl = SYMBOL_BLOCK_VALUE (symbol); /* APPLE LOCAL begin address ranges */ return BLOCK_LOWEST_PC (bl); /* APPLE LOCAL end address ranges */ } } msymbol = lookup_minimal_symbol_by_pc (pc); if (msymbol) { CORE_ADDR fstart = SYMBOL_VALUE_ADDRESS (msymbol); if (find_pc_section (fstart)) return fstart; } return 0; } /* Return the symbol for the function executing in frame FRAME. */ struct symbol * get_frame_function (struct frame_info *frame) { struct block *bl = get_frame_block (frame, 0); if (bl == 0) return 0; return block_function (bl); } /* Return the function containing pc value PC in section SECTION. Returns 0 if function is not known. */ struct symbol * find_pc_sect_function (CORE_ADDR pc, struct bfd_section *section) { 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 (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 bfd_section *cache_pc_function_section = NULL; /* Clear cache, e.g. when symbol table is discarded. */ void clear_pc_function_cache (void) { 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. */ /* Backward compatibility, no section argument. */ int find_pc_partial_function (CORE_ADDR pc, char **name, CORE_ADDR *address, CORE_ADDR *endaddr) { struct bfd_section *section; 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; /* To ensure that the symbol returned belongs to the correct setion (and that the last [random] symbol from the previous section isn't returned) try to find the section containing PC. First try the overlay code (which by default returns NULL); and second try the normal section code (which almost always succeeds). */ section = find_pc_overlay (pc); if (section == NULL) { struct obj_section *obj_section = find_pc_section (pc); if (obj_section == NULL) section = NULL; else section = obj_section->the_bfd_section; } 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; 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); /* APPLE LOCAL begin address ranges */ if (f != NULL && (msymbol == NULL || (BLOCK_LOWEST_PC (SYMBOL_BLOCK_VALUE (f)) >= SYMBOL_VALUE_ADDRESS (msymbol)))) { cache_pc_function_low = BLOCK_LOWEST_PC (SYMBOL_BLOCK_VALUE (f)); if (BLOCK_RANGES (SYMBOL_BLOCK_VALUE (f))) cache_pc_function_high = BLOCK_HIGHEST_PC (SYMBOL_BLOCK_VALUE (f)); else cache_pc_function_high = BLOCK_END (SYMBOL_BLOCK_VALUE (f)); /* APPLE LOCAL end address ranges */ cache_pc_function_name = DEPRECATED_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 = DEPRECATED_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 = DEPRECATED_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; DEPRECATED_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 (DEPRECATED_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; } /* 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 (struct block *block) { struct frame_info *frame; CORE_ADDR start; CORE_ADDR end; CORE_ADDR calling_pc; 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; calling_pc = get_frame_address_in_block (frame); /* APPLE LOCAL begin address ranges */ if (block_contains_pc (block, calling_pc)) /* APPLE LOCAL end address ranges */ return frame; } }