diff options
Diffstat (limited to 'gdb/dwarf2-frame.c')
| -rw-r--r-- | gdb/dwarf2-frame.c | 210 |
1 files changed, 111 insertions, 99 deletions
diff --git a/gdb/dwarf2-frame.c b/gdb/dwarf2-frame.c index c4cd9f3d3ef..e48fad9cd06 100644 --- a/gdb/dwarf2-frame.c +++ b/gdb/dwarf2-frame.c @@ -38,12 +38,17 @@ #include "complaints.h" #include "dwarf2-frame.h" +struct comp_unit; + /* Call Frame Information (CFI). */ /* Common Information Entry (CIE). */ struct dwarf2_cie { + /* Computation Unit for this CIE. */ + struct comp_unit *unit; + /* Offset into the .debug_frame section where this CIE was found. Used to identify this CIE. */ ULONGEST cie_pointer; @@ -68,6 +73,9 @@ struct dwarf2_cie /* Encoding of addresses. */ gdb_byte encoding; + /* Target address size in bytes. */ + int addr_size; + /* True if a 'z' augmentation existed. */ unsigned char saw_z_augmentation; @@ -104,10 +112,44 @@ struct dwarf2_fde struct dwarf2_fde *next; }; +/* A minimal decoding of DWARF2 compilation units. We only decode + what's needed to get to the call frame information. */ + +struct comp_unit +{ + /* Keep the bfd convenient. */ + bfd *abfd; + + struct objfile *objfile; + + /* Linked list of CIEs for this object. */ + struct dwarf2_cie *cie; + + /* Pointer to the .debug_frame section loaded into memory. */ + gdb_byte *dwarf_frame_buffer; + + /* Length of the loaded .debug_frame section. */ + unsigned long dwarf_frame_size; + + /* Pointer to the .debug_frame section. */ + asection *dwarf_frame_section; + + /* Base for DW_EH_PE_datarel encodings. */ + bfd_vma dbase; + + /* Base for DW_EH_PE_textrel encodings. */ + bfd_vma tbase; +}; + static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc); static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, int eh_frame_p); + +static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding, + int ptr_len, gdb_byte *buf, + unsigned int *bytes_read_ptr, + CORE_ADDR func_base); /* Structure describing a frame state. */ @@ -299,13 +341,14 @@ register %s (#%d) at 0x%s"), } static CORE_ADDR -execute_stack_op (gdb_byte *exp, ULONGEST len, +execute_stack_op (gdb_byte *exp, ULONGEST len, int addr_size, struct frame_info *next_frame, CORE_ADDR initial) { struct dwarf_expr_context *ctx; CORE_ADDR result; ctx = new_dwarf_expr_context (); + ctx->addr_size = addr_size; ctx->baton = next_frame; ctx->read_reg = read_reg; ctx->read_mem = read_mem; @@ -326,10 +369,11 @@ execute_stack_op (gdb_byte *exp, ULONGEST len, static void -execute_cfa_program (gdb_byte *insn_ptr, gdb_byte *insn_end, - struct frame_info *next_frame, - struct dwarf2_frame_state *fs, int eh_frame_p) +execute_cfa_program (struct dwarf2_fde *fde, gdb_byte *insn_ptr, + gdb_byte *insn_end, struct frame_info *next_frame, + struct dwarf2_frame_state *fs) { + int eh_frame_p = fde->eh_frame_p; CORE_ADDR pc = frame_pc_unwind (next_frame); int bytes_read; struct gdbarch *gdbarch = get_frame_arch (next_frame); @@ -362,7 +406,12 @@ execute_cfa_program (gdb_byte *insn_ptr, gdb_byte *insn_end, switch (insn) { case DW_CFA_set_loc: - fs->pc = dwarf2_read_address (insn_ptr, insn_end, &bytes_read); + fs->pc = read_encoded_value (fde->cie->unit, fde->cie->encoding, + fde->cie->addr_size, insn_ptr, + &bytes_read, fde->initial_location); + /* Apply the objfile offset for relocatable objects. */ + fs->pc += ANOFFSET (fde->cie->unit->objfile->section_offsets, + SECT_OFF_TEXT (fde->cie->unit->objfile)); insn_ptr += bytes_read; break; @@ -813,6 +862,9 @@ struct dwarf2_frame_cache /* Return address register. */ struct dwarf2_frame_state_reg retaddr_reg; + + /* Target address size in bytes. */ + int addr_size; }; static struct dwarf2_frame_cache * @@ -863,21 +915,21 @@ dwarf2_frame_cache (struct frame_info *next_frame, void **this_cache) fs->data_align = fde->cie->data_alignment_factor; fs->code_align = fde->cie->code_alignment_factor; fs->retaddr_column = fde->cie->return_address_register; + cache->addr_size = fde->cie->addr_size; /* Check for "quirks" - known bugs in producers. */ dwarf2_frame_find_quirks (fs, fde); /* First decode all the insns in the CIE. */ - execute_cfa_program (fde->cie->initial_instructions, - fde->cie->end, next_frame, fs, fde->eh_frame_p); + execute_cfa_program (fde, fde->cie->initial_instructions, + fde->cie->end, next_frame, fs); /* Save the initialized register set. */ fs->initial = fs->regs; fs->initial.reg = dwarf2_frame_state_copy_regs (&fs->regs); /* Then decode the insns in the FDE up to our target PC. */ - execute_cfa_program (fde->instructions, fde->end, next_frame, fs, - fde->eh_frame_p); + execute_cfa_program (fde, fde->instructions, fde->end, next_frame, fs); /* Caclulate the CFA. */ switch (fs->cfa_how) @@ -892,7 +944,8 @@ dwarf2_frame_cache (struct frame_info *next_frame, void **this_cache) case CFA_EXP: cache->cfa = - execute_stack_op (fs->cfa_exp, fs->cfa_exp_len, next_frame, 0); + execute_stack_op (fs->cfa_exp, fs->cfa_exp_len, + cache->addr_size, next_frame, 0); break; default: @@ -1089,7 +1142,7 @@ dwarf2_frame_prev_register (struct frame_info *next_frame, void **this_cache, *lvalp = lval_memory; *addrp = execute_stack_op (cache->reg[regnum].loc.exp, cache->reg[regnum].exp_len, - next_frame, cache->cfa); + cache->addr_size, next_frame, cache->cfa); *realnump = -1; if (valuep) { @@ -1117,7 +1170,8 @@ dwarf2_frame_prev_register (struct frame_info *next_frame, void **this_cache, store_unsigned_integer (valuep, register_size (gdbarch, regnum), execute_stack_op (cache->reg[regnum].loc.exp, cache->reg[regnum].exp_len, - next_frame, cache->cfa)); + cache->addr_size, next_frame, + cache->cfa)); break; case DWARF2_FRAME_REG_UNSPECIFIED: @@ -1261,35 +1315,6 @@ dwarf2_frame_base_sniffer (struct frame_info *next_frame) return NULL; } -/* A minimal decoding of DWARF2 compilation units. We only decode - what's needed to get to the call frame information. */ - -struct comp_unit -{ - /* Keep the bfd convenient. */ - bfd *abfd; - - struct objfile *objfile; - - /* Linked list of CIEs for this object. */ - struct dwarf2_cie *cie; - - /* Pointer to the .debug_frame section loaded into memory. */ - gdb_byte *dwarf_frame_buffer; - - /* Length of the loaded .debug_frame section. */ - unsigned long dwarf_frame_size; - - /* Pointer to the .debug_frame section. */ - asection *dwarf_frame_section; - - /* Base for DW_EH_PE_datarel encodings. */ - bfd_vma dbase; - - /* Base for DW_EH_PE_textrel encodings. */ - bfd_vma tbase; -}; - const struct objfile_data *dwarf2_frame_objfile_data; static unsigned int @@ -1417,32 +1442,11 @@ encoding_for_size (unsigned int size) } } -static unsigned int -size_of_encoded_value (gdb_byte encoding) -{ - if (encoding == DW_EH_PE_omit) - return 0; - - switch (encoding & 0x07) - { - case DW_EH_PE_absptr: - return TYPE_LENGTH (builtin_type_void_data_ptr); - case DW_EH_PE_udata2: - return 2; - case DW_EH_PE_udata4: - return 4; - case DW_EH_PE_udata8: - return 8; - default: - internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding")); - } -} - static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding, - gdb_byte *buf, unsigned int *bytes_read_ptr) + int ptr_len, gdb_byte *buf, unsigned int *bytes_read_ptr, + CORE_ADDR func_base) { - int ptr_len = size_of_encoded_value (DW_EH_PE_absptr); ptrdiff_t offset; CORE_ADDR base; @@ -1470,12 +1474,7 @@ read_encoded_value (struct comp_unit *unit, gdb_byte encoding, base = unit->tbase; break; case DW_EH_PE_funcrel: - /* FIXME: kettenis/20040501: For now just pretend - DW_EH_PE_funcrel is equivalent to DW_EH_PE_absptr. For - reading the initial location of an FDE it should be treated - as such, and currently that's the only place where this code - is used. */ - base = 0; + base = func_base; break; case DW_EH_PE_aligned: base = 0; @@ -1561,6 +1560,7 @@ add_cie (struct comp_unit *unit, struct dwarf2_cie *cie) { cie->next = unit->cie; unit->cie = cie; + cie->unit = unit; } /* Find the FDE for *PC. Return a pointer to the FDE, and store the @@ -1685,6 +1685,13 @@ decode_frame_entry_1 (struct comp_unit *unit, gdb_byte *start, int eh_frame_p) depends on the target address size. */ cie->encoding = DW_EH_PE_absptr; + /* The target address size. For .eh_frame FDEs this is considered + equal to the size of a target pointer. For .dwarf_frame FDEs, + this is supposed to be the target address size from the associated + CU header. FIXME: We do not have a good way to determine the + latter. Always use the target pointer size for now. */ + cie->addr_size = gdbarch_ptr_bit (current_gdbarch) / TARGET_CHAR_BIT; + /* We'll determine the final value later, but we need to initialize it conservatively. */ cie->signal_frame = 0; @@ -1773,7 +1780,8 @@ decode_frame_entry_1 (struct comp_unit *unit, gdb_byte *start, int eh_frame_p) { /* Skip. Avoid indirection since we throw away the result. */ gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect; - read_encoded_value (unit, encoding, buf, &bytes_read); + read_encoded_value (unit, encoding, cie->addr_size, + buf, &bytes_read, 0); buf += bytes_read; augmentation++; } @@ -1837,11 +1845,13 @@ decode_frame_entry_1 (struct comp_unit *unit, gdb_byte *start, int eh_frame_p) gdb_assert (fde->cie != NULL); fde->initial_location = - read_encoded_value (unit, fde->cie->encoding, buf, &bytes_read); + read_encoded_value (unit, fde->cie->encoding, fde->cie->addr_size, + buf, &bytes_read, 0); buf += bytes_read; fde->address_range = - read_encoded_value (unit, fde->cie->encoding & 0x0f, buf, &bytes_read); + read_encoded_value (unit, fde->cie->encoding & 0x0f, + fde->cie->addr_size, buf, &bytes_read, 0); buf += bytes_read; /* A 'z' augmentation in the CIE implies the presence of an @@ -1975,14 +1985,16 @@ extern gdb_byte *dwarf2_read_section (struct objfile *objfile, asection *sectp); void dwarf2_build_frame_info (struct objfile *objfile) { - struct comp_unit unit; + struct comp_unit *unit; gdb_byte *frame_ptr; /* Build a minimal decoding of the DWARF2 compilation unit. */ - unit.abfd = objfile->obfd; - unit.objfile = objfile; - unit.dbase = 0; - unit.tbase = 0; + unit = (struct comp_unit *) obstack_alloc (&objfile->objfile_obstack, + sizeof (struct comp_unit)); + unit->abfd = objfile->obfd; + unit->objfile = objfile; + unit->dbase = 0; + unit->tbase = 0; /* First add the information from the .eh_frame section. That way, the FDEs from that section are searched last. */ @@ -1990,43 +2002,43 @@ dwarf2_build_frame_info (struct objfile *objfile) { asection *got, *txt; - unit.cie = NULL; - unit.dwarf_frame_buffer = dwarf2_read_section (objfile, - dwarf_eh_frame_section); + unit->cie = NULL; + unit->dwarf_frame_buffer = dwarf2_read_section (objfile, + dwarf_eh_frame_section); - unit.dwarf_frame_size = bfd_get_section_size (dwarf_eh_frame_section); - unit.dwarf_frame_section = dwarf_eh_frame_section; + unit->dwarf_frame_size = bfd_get_section_size (dwarf_eh_frame_section); + unit->dwarf_frame_section = dwarf_eh_frame_section; /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base that is used for the i386/amd64 target, which currently is the only target in GCC that supports/uses the DW_EH_PE_datarel encoding. */ - got = bfd_get_section_by_name (unit.abfd, ".got"); + got = bfd_get_section_by_name (unit->abfd, ".got"); if (got) - unit.dbase = got->vma; + unit->dbase = got->vma; /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64 so far. */ - txt = bfd_get_section_by_name (unit.abfd, ".text"); + txt = bfd_get_section_by_name (unit->abfd, ".text"); if (txt) - unit.tbase = txt->vma; + unit->tbase = txt->vma; - frame_ptr = unit.dwarf_frame_buffer; - while (frame_ptr < unit.dwarf_frame_buffer + unit.dwarf_frame_size) - frame_ptr = decode_frame_entry (&unit, frame_ptr, 1); + frame_ptr = unit->dwarf_frame_buffer; + while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) + frame_ptr = decode_frame_entry (unit, frame_ptr, 1); } if (dwarf_frame_section) { - unit.cie = NULL; - unit.dwarf_frame_buffer = dwarf2_read_section (objfile, - dwarf_frame_section); - unit.dwarf_frame_size = bfd_get_section_size (dwarf_frame_section); - unit.dwarf_frame_section = dwarf_frame_section; - - frame_ptr = unit.dwarf_frame_buffer; - while (frame_ptr < unit.dwarf_frame_buffer + unit.dwarf_frame_size) - frame_ptr = decode_frame_entry (&unit, frame_ptr, 0); + unit->cie = NULL; + unit->dwarf_frame_buffer = dwarf2_read_section (objfile, + dwarf_frame_section); + unit->dwarf_frame_size = bfd_get_section_size (dwarf_frame_section); + unit->dwarf_frame_section = dwarf_frame_section; + + frame_ptr = unit->dwarf_frame_buffer; + while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) + frame_ptr = decode_frame_entry (unit, frame_ptr, 0); } } |