X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Ffindvar.c;h=e89ee37ffc7e788e10e0c87494fcc190e646203a;hb=b3a7d1711e4557811865333a0ac96fc16b750869;hp=c3550b43f8f66ee5e920b174a45da6764822271c;hpb=901461f8eb407af99c049a381fc985baefce179c;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/findvar.c b/gdb/findvar.c index c3550b43f8..e89ee37ffc 100644 --- a/gdb/findvar.c +++ b/gdb/findvar.c @@ -1,6 +1,6 @@ /* Find a variable's value in memory, for GDB, the GNU debugger. - Copyright (C) 1986-2013 Free Software Foundation, Inc. + Copyright (C) 1986-2019 Free Software Foundation, Inc. This file is part of GDB. @@ -25,15 +25,14 @@ #include "gdbcore.h" #include "inferior.h" #include "target.h" -#include "gdb_string.h" -#include "gdb_assert.h" -#include "floatformat.h" #include "symfile.h" /* for overlay functions */ #include "regcache.h" #include "user-regs.h" #include "block.h" #include "objfiles.h" #include "language.h" +#include "dwarf2loc.h" +#include "common/selftest.h" /* Basic byte-swapping routines. All 'extract' functions return a host-format integer from a target-format integer at ADDR which is @@ -47,70 +46,54 @@ you lose #endif -LONGEST -extract_signed_integer (const gdb_byte *addr, int len, - enum bfd_endian byte_order) +template +T +extract_integer (const gdb_byte *addr, int len, enum bfd_endian byte_order) { - LONGEST retval; + typename std::make_unsigned::type retval = 0; const unsigned char *p; const unsigned char *startaddr = addr; const unsigned char *endaddr = startaddr + len; - if (len > (int) sizeof (LONGEST)) + if (len > (int) sizeof (T)) error (_("\ That operation is not available on integers of more than %d bytes."), - (int) sizeof (LONGEST)); + (int) sizeof (T)); /* Start at the most significant end of the integer, and work towards the least significant. */ if (byte_order == BFD_ENDIAN_BIG) { p = startaddr; - /* Do the sign extension once at the start. */ - retval = ((LONGEST) * p ^ 0x80) - 0x80; - for (++p; p < endaddr; ++p) + if (std::is_signed::value) + { + /* Do the sign extension once at the start. */ + retval = ((LONGEST) * p ^ 0x80) - 0x80; + ++p; + } + for (; p < endaddr; ++p) retval = (retval << 8) | *p; } else { p = endaddr - 1; - /* Do the sign extension once at the start. */ - retval = ((LONGEST) * p ^ 0x80) - 0x80; - for (--p; p >= startaddr; --p) + if (std::is_signed::value) + { + /* Do the sign extension once at the start. */ + retval = ((LONGEST) * p ^ 0x80) - 0x80; + --p; + } + for (; p >= startaddr; --p) retval = (retval << 8) | *p; } return retval; } -ULONGEST -extract_unsigned_integer (const gdb_byte *addr, int len, - enum bfd_endian byte_order) -{ - ULONGEST retval; - const unsigned char *p; - const unsigned char *startaddr = addr; - const unsigned char *endaddr = startaddr + len; - - if (len > (int) sizeof (ULONGEST)) - error (_("\ -That operation is not available on integers of more than %d bytes."), - (int) sizeof (ULONGEST)); - - /* Start at the most significant end of the integer, and work towards - the least significant. */ - retval = 0; - if (byte_order == BFD_ENDIAN_BIG) - { - for (p = startaddr; p < endaddr; ++p) - retval = (retval << 8) | *p; - } - else - { - for (p = endaddr - 1; p >= startaddr; --p) - retval = (retval << 8) | *p; - } - return retval; -} +/* Explicit instantiations. */ +template LONGEST extract_integer (const gdb_byte *addr, int len, + enum bfd_endian byte_order); +template ULONGEST extract_integer (const gdb_byte *addr, int len, + enum bfd_endian byte_order); /* Sometimes a long long unsigned integer can be extracted as a LONGEST value. This is done so that we can print these values @@ -170,8 +153,7 @@ extract_long_unsigned_integer (const gdb_byte *addr, int orig_len, CORE_ADDR extract_typed_address (const gdb_byte *buf, struct type *type) { - if (TYPE_CODE (type) != TYPE_CODE_PTR - && TYPE_CODE (type) != TYPE_CODE_REF) + if (TYPE_CODE (type) != TYPE_CODE_PTR && !TYPE_IS_REFERENCE (type)) internal_error (__FILE__, __LINE__, _("extract_typed_address: " "type is not a pointer or reference")); @@ -181,10 +163,10 @@ extract_typed_address (const gdb_byte *buf, struct type *type) /* All 'store' functions accept a host-format integer and store a target-format integer at ADDR which is LEN bytes long. */ - +template void -store_signed_integer (gdb_byte *addr, int len, - enum bfd_endian byte_order, LONGEST val) +store_integer (gdb_byte *addr, int len, enum bfd_endian byte_order, + T val) { gdb_byte *p; gdb_byte *startaddr = addr; @@ -210,41 +192,21 @@ store_signed_integer (gdb_byte *addr, int len, } } -void -store_unsigned_integer (gdb_byte *addr, int len, - enum bfd_endian byte_order, ULONGEST val) -{ - unsigned char *p; - unsigned char *startaddr = (unsigned char *) addr; - unsigned char *endaddr = startaddr + len; +/* Explicit instantiations. */ +template void store_integer (gdb_byte *addr, int len, + enum bfd_endian byte_order, + LONGEST val); - /* Start at the least significant end of the integer, and work towards - the most significant. */ - if (byte_order == BFD_ENDIAN_BIG) - { - for (p = endaddr - 1; p >= startaddr; --p) - { - *p = val & 0xff; - val >>= 8; - } - } - else - { - for (p = startaddr; p < endaddr; ++p) - { - *p = val & 0xff; - val >>= 8; - } - } -} +template void store_integer (gdb_byte *addr, int len, + enum bfd_endian byte_order, + ULONGEST val); /* Store the address ADDR as a pointer of type TYPE at BUF, in target form. */ void store_typed_address (gdb_byte *buf, struct type *type, CORE_ADDR addr) { - if (TYPE_CODE (type) != TYPE_CODE_PTR - && TYPE_CODE (type) != TYPE_CODE_REF) + if (TYPE_CODE (type) != TYPE_CODE_PTR && !TYPE_IS_REFERENCE (type)) internal_error (__FILE__, __LINE__, _("store_typed_address: " "type is not a pointer or reference")); @@ -252,7 +214,46 @@ store_typed_address (gdb_byte *buf, struct type *type, CORE_ADDR addr) gdbarch_address_to_pointer (get_type_arch (type), type, buf, addr); } +/* Copy a value from SOURCE of size SOURCE_SIZE bytes to DEST of size DEST_SIZE + bytes. If SOURCE_SIZE is greater than DEST_SIZE, then truncate the most + significant bytes. If SOURCE_SIZE is less than DEST_SIZE then either sign + or zero extended according to IS_SIGNED. Values are stored in memory with + endianess BYTE_ORDER. */ +void +copy_integer_to_size (gdb_byte *dest, int dest_size, const gdb_byte *source, + int source_size, bool is_signed, + enum bfd_endian byte_order) +{ + signed int size_diff = dest_size - source_size; + + /* Copy across everything from SOURCE that can fit into DEST. */ + + if (byte_order == BFD_ENDIAN_BIG && size_diff > 0) + memcpy (dest + size_diff, source, source_size); + else if (byte_order == BFD_ENDIAN_BIG && size_diff < 0) + memcpy (dest, source - size_diff, dest_size); + else + memcpy (dest, source, std::min (source_size, dest_size)); + + /* Fill the remaining space in DEST by either zero extending or sign + extending. */ + + if (size_diff > 0) + { + gdb_byte extension = 0; + if (is_signed + && ((byte_order != BFD_ENDIAN_BIG && source[source_size - 1] & 0x80) + || (byte_order == BFD_ENDIAN_BIG && source[0] & 0x80))) + extension = 0xff; + + /* Extend into MSBs of SOURCE. */ + if (byte_order == BFD_ENDIAN_BIG) + memset (dest, extension, size_diff); + else + memset (dest + source_size, extension, size_diff); + } +} /* Return a `value' with the contents of (virtual or cooked) register REGNUM as found in the specified FRAME. The register's type is @@ -266,8 +267,7 @@ value_of_register (int regnum, struct frame_info *frame) /* User registers lie completely outside of the range of normal registers. Catch them early so that the target never sees them. */ - if (regnum >= gdbarch_num_regs (gdbarch) - + gdbarch_num_pseudo_regs (gdbarch)) + if (regnum >= gdbarch_num_cooked_regs (gdbarch)) return value_of_user_reg (regnum, frame); reg_val = value_of_register_lazy (frame, regnum); @@ -284,17 +284,22 @@ value_of_register_lazy (struct frame_info *frame, int regnum) { struct gdbarch *gdbarch = get_frame_arch (frame); struct value *reg_val; + struct frame_info *next_frame; + + gdb_assert (regnum < gdbarch_num_cooked_regs (gdbarch)); + + gdb_assert (frame != NULL); - gdb_assert (regnum < (gdbarch_num_regs (gdbarch) - + gdbarch_num_pseudo_regs (gdbarch))); + next_frame = get_next_frame_sentinel_okay (frame); - /* We should have a valid (i.e. non-sentinel) frame. */ - gdb_assert (frame_id_p (get_frame_id (frame))); + /* We should have a valid next frame. */ + gdb_assert (frame_id_p (get_frame_id (next_frame))); reg_val = allocate_value_lazy (register_type (gdbarch, regnum)); VALUE_LVAL (reg_val) = lval_register; VALUE_REGNUM (reg_val) = regnum; - VALUE_FRAME_ID (reg_val) = get_frame_id (frame); + VALUE_NEXT_FRAME_ID (reg_val) = get_frame_id (next_frame); + return reg_val; } @@ -338,14 +343,13 @@ address_to_signed_pointer (struct gdbarch *gdbarch, struct type *type, store_signed_integer (buf, TYPE_LENGTH (type), byte_order, addr); } -/* Will calling read_var_value or locate_var_value on SYM end - up caring what frame it is being evaluated relative to? SYM must - be non-NULL. */ -int -symbol_read_needs_frame (struct symbol *sym) +/* See value.h. */ + +enum symbol_needs_kind +symbol_read_needs (struct symbol *sym) { if (SYMBOL_COMPUTED_OPS (sym) != NULL) - return SYMBOL_COMPUTED_OPS (sym)->read_needs_frame (sym); + return SYMBOL_COMPUTED_OPS (sym)->get_symbol_read_needs (sym); switch (SYMBOL_CLASS (sym)) { @@ -359,7 +363,7 @@ symbol_read_needs_frame (struct symbol *sym) case LOC_REF_ARG: case LOC_REGPARM_ADDR: case LOC_LOCAL: - return 1; + return SYMBOL_NEEDS_FRAME; case LOC_UNDEF: case LOC_CONST: @@ -375,9 +379,17 @@ symbol_read_needs_frame (struct symbol *sym) case LOC_CONST_BYTES: case LOC_UNRESOLVED: case LOC_OPTIMIZED_OUT: - return 0; + return SYMBOL_NEEDS_NONE; } - return 1; + return SYMBOL_NEEDS_FRAME; +} + +/* See value.h. */ + +int +symbol_read_needs_frame (struct symbol *sym) +{ + return symbol_read_needs (sym) == SYMBOL_NEEDS_FRAME; } /* Private data to be used with minsym_lookup_iterator_cb. */ @@ -390,10 +402,7 @@ struct minsym_lookup_data /* The field where the callback should store the minimal symbol if found. It should be initialized to NULL before the search is started. */ - struct minimal_symbol *result; - - /* The objfile in which the symbol was found. */ - struct objfile *objfile; + struct bound_minimal_symbol result; }; /* A callback function for gdbarch_iterate_over_objfiles_in_search_order. @@ -406,24 +415,180 @@ minsym_lookup_iterator_cb (struct objfile *objfile, void *cb_data) { struct minsym_lookup_data *data = (struct minsym_lookup_data *) cb_data; - gdb_assert (data->result == NULL); + gdb_assert (data->result.minsym == NULL); data->result = lookup_minimal_symbol (data->name, NULL, objfile); - data->objfile = objfile; /* The iterator should stop iff a match was found. */ - return (data->result != NULL); + return (data->result.minsym != NULL); +} + +/* Given static link expression and the frame it lives in, look for the frame + the static links points to and return it. Return NULL if we could not find + such a frame. */ + +static struct frame_info * +follow_static_link (struct frame_info *frame, + const struct dynamic_prop *static_link) +{ + CORE_ADDR upper_frame_base; + + if (!dwarf2_evaluate_property (static_link, frame, NULL, &upper_frame_base)) + return NULL; + + /* Now climb up the stack frame until we reach the frame we are interested + in. */ + for (; frame != NULL; frame = get_prev_frame (frame)) + { + struct symbol *framefunc = get_frame_function (frame); + + /* Stacks can be quite deep: give the user a chance to stop this. */ + QUIT; + + /* If we don't know how to compute FRAME's base address, don't give up: + maybe the frame we are looking for is upper in the stace frame. */ + if (framefunc != NULL + && SYMBOL_BLOCK_OPS (framefunc) != NULL + && SYMBOL_BLOCK_OPS (framefunc)->get_frame_base != NULL + && (SYMBOL_BLOCK_OPS (framefunc)->get_frame_base (framefunc, frame) + == upper_frame_base)) + break; + } + + return frame; +} + +/* Assuming VAR is a symbol that can be reached from FRAME thanks to lexical + rules, look for the frame that is actually hosting VAR and return it. If, + for some reason, we found no such frame, return NULL. + + This kind of computation is necessary to correctly handle lexically nested + functions. + + Note that in some cases, we know what scope VAR comes from but we cannot + reach the specific frame that hosts the instance of VAR we are looking for. + For backward compatibility purposes (with old compilers), we then look for + the first frame that can host it. */ + +static struct frame_info * +get_hosting_frame (struct symbol *var, const struct block *var_block, + struct frame_info *frame) +{ + const struct block *frame_block = NULL; + + if (!symbol_read_needs_frame (var)) + return NULL; + + /* Some symbols for local variables have no block: this happens when they are + not produced by a debug information reader, for instance when GDB creates + synthetic symbols. Without block information, we must assume they are + local to FRAME. In this case, there is nothing to do. */ + else if (var_block == NULL) + return frame; + + /* We currently assume that all symbols with a location list need a frame. + This is true in practice because selecting the location description + requires to compute the CFA, hence requires a frame. However we have + tests that embed global/static symbols with null location lists. + We want to get instead of when evaluating + them so return a frame instead of raising an error. */ + else if (var_block == block_global_block (var_block) + || var_block == block_static_block (var_block)) + return frame; + + /* We have to handle the "my_func::my_local_var" notation. This requires us + to look for upper frames when we find no block for the current frame: here + and below, handle when frame_block == NULL. */ + if (frame != NULL) + frame_block = get_frame_block (frame, NULL); + + /* Climb up the call stack until reaching the frame we are looking for. */ + while (frame != NULL && frame_block != var_block) + { + /* Stacks can be quite deep: give the user a chance to stop this. */ + QUIT; + + if (frame_block == NULL) + { + frame = get_prev_frame (frame); + if (frame == NULL) + break; + frame_block = get_frame_block (frame, NULL); + } + + /* If we failed to find the proper frame, fallback to the heuristic + method below. */ + else if (frame_block == block_global_block (frame_block)) + { + frame = NULL; + break; + } + + /* Assuming we have a block for this frame: if we are at the function + level, the immediate upper lexical block is in an outer function: + follow the static link. */ + else if (BLOCK_FUNCTION (frame_block)) + { + const struct dynamic_prop *static_link + = block_static_link (frame_block); + int could_climb_up = 0; + + if (static_link != NULL) + { + frame = follow_static_link (frame, static_link); + if (frame != NULL) + { + frame_block = get_frame_block (frame, NULL); + could_climb_up = frame_block != NULL; + } + } + if (!could_climb_up) + { + frame = NULL; + break; + } + } + + else + /* We must be in some function nested lexical block. Just get the + outer block: both must share the same frame. */ + frame_block = BLOCK_SUPERBLOCK (frame_block); + } + + /* Old compilers may not provide a static link, or they may provide an + invalid one. For such cases, fallback on the old way to evaluate + non-local references: just climb up the call stack and pick the first + frame that contains the variable we are looking for. */ + if (frame == NULL) + { + frame = block_innermost_frame (var_block); + if (frame == NULL) + { + if (BLOCK_FUNCTION (var_block) + && !block_inlined_p (var_block) + && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (var_block))) + error (_("No frame is currently executing in block %s."), + SYMBOL_PRINT_NAME (BLOCK_FUNCTION (var_block))); + else + error (_("No frame is currently executing in specified" + " block")); + } + } + + return frame; } /* A default implementation for the "la_read_var_value" hook in the language vector which should work in most situations. */ struct value * -default_read_var_value (struct symbol *var, struct frame_info *frame) +default_read_var_value (struct symbol *var, const struct block *var_block, + struct frame_info *frame) { struct value *v; struct type *type = SYMBOL_TYPE (var); CORE_ADDR addr; + enum symbol_needs_kind sym_need; /* Call check_typedef on our type to make sure that, if TYPE is a TYPE_CODE_TYPEDEF, its length is set to the length of the target type @@ -432,8 +597,14 @@ default_read_var_value (struct symbol *var, struct frame_info *frame) set the returned value type description correctly. */ check_typedef (type); - if (symbol_read_needs_frame (var)) - gdb_assert (frame); + sym_need = symbol_read_needs (var); + if (sym_need == SYMBOL_NEEDS_FRAME) + gdb_assert (frame != NULL); + else if (sym_need == SYMBOL_NEEDS_REGISTERS && !target_has_registers) + error (_("Cannot read `%s' without registers"), SYMBOL_PRINT_NAME (var)); + + if (frame != NULL) + frame = get_hosting_frame (var, var_block, frame); if (SYMBOL_COMPUTED_OPS (var) != NULL) return SYMBOL_COMPUTED_OPS (var)->read_variable (var, frame); @@ -441,7 +612,12 @@ default_read_var_value (struct symbol *var, struct frame_info *frame) switch (SYMBOL_CLASS (var)) { case LOC_CONST: - /* Put the constant back in target format. */ + if (is_dynamic_type (type)) + { + /* Value is a constant byte-sequence and needs no memory access. */ + type = resolve_dynamic_type (type, NULL, /* Unused address. */ 0); + } + /* Put the constant back in target format. */ v = allocate_value (type); store_signed_integer (value_contents_raw (v), TYPE_LENGTH (type), gdbarch_byte_order (get_type_arch (type)), @@ -454,9 +630,9 @@ default_read_var_value (struct symbol *var, struct frame_info *frame) v = allocate_value (type); if (overlay_debugging) { - CORE_ADDR addr + addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), - SYMBOL_OBJ_SECTION (SYMBOL_OBJFILE (var), + SYMBOL_OBJ_SECTION (symbol_objfile (var), var)); store_typed_address (value_contents_raw (v), type, addr); @@ -468,6 +644,11 @@ default_read_var_value (struct symbol *var, struct frame_info *frame) return v; case LOC_CONST_BYTES: + if (is_dynamic_type (type)) + { + /* Value is a constant byte-sequence and needs no memory access. */ + type = resolve_dynamic_type (type, NULL, /* Unused address. */ 0); + } v = allocate_value (type); memcpy (value_contents_raw (v), SYMBOL_VALUE_BYTES (var), TYPE_LENGTH (type)); @@ -477,7 +658,7 @@ default_read_var_value (struct symbol *var, struct frame_info *frame) case LOC_STATIC: if (overlay_debugging) addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var), - SYMBOL_OBJ_SECTION (SYMBOL_OBJFILE (var), + SYMBOL_OBJ_SECTION (symbol_objfile (var), var)); else addr = SYMBOL_VALUE_ADDRESS (var); @@ -519,10 +700,10 @@ default_read_var_value (struct symbol *var, struct frame_info *frame) case LOC_BLOCK: if (overlay_debugging) addr = symbol_overlayed_address - (BLOCK_START (SYMBOL_BLOCK_VALUE (var)), SYMBOL_OBJ_SECTION (SYMBOL_OBJFILE (var), - var)); + (BLOCK_ENTRY_PC (SYMBOL_BLOCK_VALUE (var)), + SYMBOL_OBJ_SECTION (symbol_objfile (var), var)); else - addr = BLOCK_START (SYMBOL_BLOCK_VALUE (var)); + addr = BLOCK_ENTRY_PC (SYMBOL_BLOCK_VALUE (var)); break; case LOC_REGISTER: @@ -569,21 +750,36 @@ default_read_var_value (struct symbol *var, struct frame_info *frame) lookup_data.name = SYMBOL_LINKAGE_NAME (var); gdbarch_iterate_over_objfiles_in_search_order - (get_objfile_arch (SYMBOL_SYMTAB (var)->objfile), + (symbol_arch (var), minsym_lookup_iterator_cb, &lookup_data, - SYMBOL_SYMTAB (var)->objfile); - msym = lookup_data.result; + symbol_objfile (var)); + msym = lookup_data.result.minsym; + /* If we can't find the minsym there's a problem in the symbol info. + The symbol exists in the debug info, but it's missing in the minsym + table. */ if (msym == NULL) - error (_("No global symbol \"%s\"."), SYMBOL_LINKAGE_NAME (var)); - if (overlay_debugging) - addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (msym), - SYMBOL_OBJ_SECTION (lookup_data.objfile, - msym)); + { + const char *flavour_name + = objfile_flavour_name (symbol_objfile (var)); + + /* We can't get here unless we've opened the file, so flavour_name + can't be NULL. */ + gdb_assert (flavour_name != NULL); + error (_("Missing %s symbol \"%s\"."), + flavour_name, SYMBOL_LINKAGE_NAME (var)); + } + obj_section = MSYMBOL_OBJ_SECTION (lookup_data.result.objfile, msym); + /* Relocate address, unless there is no section or the variable is + a TLS variable. */ + if (obj_section == NULL + || (obj_section->the_bfd_section->flags & SEC_THREAD_LOCAL) != 0) + addr = MSYMBOL_VALUE_RAW_ADDRESS (msym); else - addr = SYMBOL_VALUE_ADDRESS (msym); - - obj_section = SYMBOL_OBJ_SECTION (lookup_data.objfile, msym); + addr = BMSYMBOL_VALUE_ADDRESS (lookup_data.result); + if (overlay_debugging) + addr = symbol_overlayed_address (addr, obj_section); + /* Determine address of TLS variable. */ if (obj_section && (obj_section->the_bfd_section->flags & SEC_THREAD_LOCAL) != 0) addr = target_translate_tls_address (obj_section->objfile, addr); @@ -591,6 +787,8 @@ default_read_var_value (struct symbol *var, struct frame_info *frame) break; case LOC_OPTIMIZED_OUT: + if (is_dynamic_type (type)) + type = resolve_dynamic_type (type, NULL, /* Unused address. */ 0); return allocate_optimized_out_value (type); default: @@ -606,28 +804,36 @@ default_read_var_value (struct symbol *var, struct frame_info *frame) /* Calls VAR's language la_read_var_value hook with the given arguments. */ struct value * -read_var_value (struct symbol *var, struct frame_info *frame) +read_var_value (struct symbol *var, const struct block *var_block, + struct frame_info *frame) { const struct language_defn *lang = language_def (SYMBOL_LANGUAGE (var)); gdb_assert (lang != NULL); gdb_assert (lang->la_read_var_value != NULL); - return lang->la_read_var_value (var, frame); + return lang->la_read_var_value (var, var_block, frame); } /* Install default attributes for register values. */ struct value * -default_value_from_register (struct type *type, int regnum, - struct frame_info *frame) +default_value_from_register (struct gdbarch *gdbarch, struct type *type, + int regnum, struct frame_id frame_id) { - struct gdbarch *gdbarch = get_frame_arch (frame); int len = TYPE_LENGTH (type); struct value *value = allocate_value (type); + struct frame_info *frame; VALUE_LVAL (value) = lval_register; - VALUE_FRAME_ID (value) = get_frame_id (frame); + frame = frame_find_by_id (frame_id); + + if (frame == NULL) + frame_id = null_frame_id; + else + frame_id = get_frame_id (get_next_frame_sentinel_okay (frame)); + + VALUE_NEXT_FRAME_ID (value) = frame_id; VALUE_REGNUM (value) = regnum; /* Any structure stored in more than one register will always be @@ -656,10 +862,10 @@ void read_frame_register_value (struct value *value, struct frame_info *frame) { struct gdbarch *gdbarch = get_frame_arch (frame); - int offset = 0; - int reg_offset = value_offset (value); + LONGEST offset = 0; + LONGEST reg_offset = value_offset (value); int regnum = VALUE_REGNUM (value); - int len = TYPE_LENGTH (check_typedef (value_type (value))); + int len = type_length_units (check_typedef (value_type (value))); gdb_assert (VALUE_LVAL (value) == lval_register); @@ -674,13 +880,7 @@ read_frame_register_value (struct value *value, struct frame_info *frame) while (len > 0) { struct value *regval = get_frame_register_value (frame, regnum); - int reg_len = TYPE_LENGTH (value_type (regval)) - reg_offset; - - if (value_optimized_out (regval)) - { - set_value_optimized_out (value, 1); - break; - } + int reg_len = type_length_units (value_type (regval)) - reg_offset; /* If the register length is larger than the number of bytes remaining to copy, then only copy the appropriate bytes. */ @@ -718,7 +918,7 @@ value_from_register (struct type *type, int regnum, struct frame_info *frame) including the location. */ v = allocate_value (type); VALUE_LVAL (v) = lval_register; - VALUE_FRAME_ID (v) = get_frame_id (frame); + VALUE_NEXT_FRAME_ID (v) = get_frame_id (get_next_frame_sentinel_okay (frame)); VALUE_REGNUM (v) = regnum; ok = gdbarch_register_to_value (gdbarch, frame, regnum, type1, value_contents_raw (v), &optim, @@ -727,7 +927,7 @@ value_from_register (struct type *type, int regnum, struct frame_info *frame) if (!ok) { if (optim) - set_value_optimized_out (v, 1); + mark_value_bytes_optimized_out (v, 0, TYPE_LENGTH (type)); if (unavail) mark_value_bytes_unavailable (v, 0, TYPE_LENGTH (type)); } @@ -735,7 +935,8 @@ value_from_register (struct type *type, int regnum, struct frame_info *frame) else { /* Construct the value. */ - v = gdbarch_value_from_register (gdbarch, type, regnum, frame); + v = gdbarch_value_from_register (gdbarch, type, + regnum, get_frame_id (frame)); /* Get the data. */ read_frame_register_value (v, frame); @@ -744,18 +945,52 @@ value_from_register (struct type *type, int regnum, struct frame_info *frame) return v; } -/* Return contents of register REGNUM in frame FRAME as address, - interpreted as value of type TYPE. Will abort if register - value is not available. */ +/* Return contents of register REGNUM in frame FRAME as address. + Will abort if register value is not available. */ CORE_ADDR -address_from_register (struct type *type, int regnum, struct frame_info *frame) +address_from_register (int regnum, struct frame_info *frame) { + struct gdbarch *gdbarch = get_frame_arch (frame); + struct type *type = builtin_type (gdbarch)->builtin_data_ptr; struct value *value; CORE_ADDR result; + int regnum_max_excl = gdbarch_num_cooked_regs (gdbarch); + + if (regnum < 0 || regnum >= regnum_max_excl) + error (_("Invalid register #%d, expecting 0 <= # < %d"), regnum, + regnum_max_excl); + + /* This routine may be called during early unwinding, at a time + where the ID of FRAME is not yet known. Calling value_from_register + would therefore abort in get_frame_id. However, since we only need + a temporary value that is never used as lvalue, we actually do not + really need to set its VALUE_NEXT_FRAME_ID. Therefore, we re-implement + the core of value_from_register, but use the null_frame_id. */ + + /* Some targets require a special conversion routine even for plain + pointer types. Avoid constructing a value object in those cases. */ + if (gdbarch_convert_register_p (gdbarch, regnum, type)) + { + gdb_byte *buf = (gdb_byte *) alloca (TYPE_LENGTH (type)); + int optim, unavail, ok; + + ok = gdbarch_register_to_value (gdbarch, frame, regnum, type, + buf, &optim, &unavail); + if (!ok) + { + /* This function is used while computing a location expression. + Complain about the value being optimized out, rather than + letting value_as_address complain about some random register + the expression depends on not being saved. */ + error_value_optimized_out (); + } - value = value_from_register (type, regnum, frame); - gdb_assert (value); + return unpack_long (type, buf); + } + + value = gdbarch_value_from_register (gdbarch, type, regnum, null_frame_id); + read_frame_register_value (value, frame); if (value_optimized_out (value)) { @@ -768,8 +1003,97 @@ address_from_register (struct type *type, int regnum, struct frame_info *frame) result = value_as_address (value); release_value (value); - value_free (value); return result; } +#if GDB_SELF_TEST +namespace selftests { +namespace findvar_tests { + +/* Function to test copy_integer_to_size. Store SOURCE_VAL with size + SOURCE_SIZE to a buffer, making sure no sign extending happens at this + stage. Copy buffer to a new buffer using copy_integer_to_size. Extract + copied value and compare to DEST_VALU. Copy again with a signed + copy_integer_to_size and compare to DEST_VALS. Do everything for both + LITTLE and BIG target endians. Use unsigned values throughout to make + sure there are no implicit sign extensions. */ + +static void +do_cint_test (ULONGEST dest_valu, ULONGEST dest_vals, int dest_size, + ULONGEST src_val, int src_size) +{ + for (int i = 0; i < 2 ; i++) + { + gdb_byte srcbuf[sizeof (ULONGEST)] = {}; + gdb_byte destbuf[sizeof (ULONGEST)] = {}; + enum bfd_endian byte_order = i ? BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE; + + /* Fill the src buffer (and later the dest buffer) with non-zero junk, + to ensure zero extensions aren't hidden. */ + memset (srcbuf, 0xaa, sizeof (srcbuf)); + + /* Store (and later extract) using unsigned to ensure there are no sign + extensions. */ + store_unsigned_integer (srcbuf, src_size, byte_order, src_val); + + /* Test unsigned. */ + memset (destbuf, 0xaa, sizeof (destbuf)); + copy_integer_to_size (destbuf, dest_size, srcbuf, src_size, false, + byte_order); + SELF_CHECK (dest_valu == extract_unsigned_integer (destbuf, dest_size, + byte_order)); + + /* Test signed. */ + memset (destbuf, 0xaa, sizeof (destbuf)); + copy_integer_to_size (destbuf, dest_size, srcbuf, src_size, true, + byte_order); + SELF_CHECK (dest_vals == extract_unsigned_integer (destbuf, dest_size, + byte_order)); + } +} + +static void +copy_integer_to_size_test () +{ + /* Destination is bigger than the source, which has the signed bit unset. */ + do_cint_test (0x12345678, 0x12345678, 8, 0x12345678, 4); + do_cint_test (0x345678, 0x345678, 8, 0x12345678, 3); + + /* Destination is bigger than the source, which has the signed bit set. */ + do_cint_test (0xdeadbeef, 0xffffffffdeadbeef, 8, 0xdeadbeef, 4); + do_cint_test (0xadbeef, 0xffffffffffadbeef, 8, 0xdeadbeef, 3); + + /* Destination is smaller than the source. */ + do_cint_test (0x5678, 0x5678, 2, 0x12345678, 3); + do_cint_test (0xbeef, 0xbeef, 2, 0xdeadbeef, 3); + + /* Destination and source are the same size. */ + do_cint_test (0x8765432112345678, 0x8765432112345678, 8, 0x8765432112345678, + 8); + do_cint_test (0x432112345678, 0x432112345678, 6, 0x8765432112345678, 6); + do_cint_test (0xfeedbeaddeadbeef, 0xfeedbeaddeadbeef, 8, 0xfeedbeaddeadbeef, + 8); + do_cint_test (0xbeaddeadbeef, 0xbeaddeadbeef, 6, 0xfeedbeaddeadbeef, 6); + + /* Destination is bigger than the source. Source is bigger than 32bits. */ + do_cint_test (0x3412345678, 0x3412345678, 8, 0x3412345678, 6); + do_cint_test (0xff12345678, 0xff12345678, 8, 0xff12345678, 6); + do_cint_test (0x432112345678, 0x432112345678, 8, 0x8765432112345678, 6); + do_cint_test (0xff2112345678, 0xffffff2112345678, 8, 0xffffff2112345678, 6); +} + +} // namespace findvar_test +} // namespace selftests + +#endif + +void +_initialize_findvar (void) +{ +#if GDB_SELF_TEST + selftests::register_test + ("copy_integer_to_size", + selftests::findvar_tests::copy_integer_to_size_test); +#endif +}