| /* Low level packing and unpacking of values for GDB, the GNU Debugger. |
| |
| Copyright (C) 1986-2018 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 3 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, see <http://www.gnu.org/licenses/>. */ |
| |
| #include "defs.h" |
| #include "arch-utils.h" |
| #include "symtab.h" |
| #include "gdbtypes.h" |
| #include "value.h" |
| #include "gdbcore.h" |
| #include "command.h" |
| #include "gdbcmd.h" |
| #include "target.h" |
| #include "language.h" |
| #include "demangle.h" |
| #include "regcache.h" |
| #include "block.h" |
| #include "target-float.h" |
| #include "objfiles.h" |
| #include "valprint.h" |
| #include "cli/cli-decode.h" |
| #include "extension.h" |
| #include <ctype.h> |
| #include "tracepoint.h" |
| #include "cp-abi.h" |
| #include "user-regs.h" |
| #include <algorithm> |
| #include "completer.h" |
| |
| /* Definition of a user function. */ |
| struct internal_function |
| { |
| /* The name of the function. It is a bit odd to have this in the |
| function itself -- the user might use a differently-named |
| convenience variable to hold the function. */ |
| char *name; |
| |
| /* The handler. */ |
| internal_function_fn handler; |
| |
| /* User data for the handler. */ |
| void *cookie; |
| }; |
| |
| /* Defines an [OFFSET, OFFSET + LENGTH) range. */ |
| |
| struct range |
| { |
| /* Lowest offset in the range. */ |
| LONGEST offset; |
| |
| /* Length of the range. */ |
| LONGEST length; |
| }; |
| |
| typedef struct range range_s; |
| |
| DEF_VEC_O(range_s); |
| |
| /* Returns true if the ranges defined by [offset1, offset1+len1) and |
| [offset2, offset2+len2) overlap. */ |
| |
| static int |
| ranges_overlap (LONGEST offset1, LONGEST len1, |
| LONGEST offset2, LONGEST len2) |
| { |
| ULONGEST h, l; |
| |
| l = std::max (offset1, offset2); |
| h = std::min (offset1 + len1, offset2 + len2); |
| return (l < h); |
| } |
| |
| /* Returns true if the first argument is strictly less than the |
| second, useful for VEC_lower_bound. We keep ranges sorted by |
| offset and coalesce overlapping and contiguous ranges, so this just |
| compares the starting offset. */ |
| |
| static int |
| range_lessthan (const range_s *r1, const range_s *r2) |
| { |
| return r1->offset < r2->offset; |
| } |
| |
| /* Returns true if RANGES contains any range that overlaps [OFFSET, |
| OFFSET+LENGTH). */ |
| |
| static int |
| ranges_contain (VEC(range_s) *ranges, LONGEST offset, LONGEST length) |
| { |
| range_s what; |
| LONGEST i; |
| |
| what.offset = offset; |
| what.length = length; |
| |
| /* We keep ranges sorted by offset and coalesce overlapping and |
| contiguous ranges, so to check if a range list contains a given |
| range, we can do a binary search for the position the given range |
| would be inserted if we only considered the starting OFFSET of |
| ranges. We call that position I. Since we also have LENGTH to |
| care for (this is a range afterall), we need to check if the |
| _previous_ range overlaps the I range. E.g., |
| |
| R |
| |---| |
| |---| |---| |------| ... |--| |
| 0 1 2 N |
| |
| I=1 |
| |
| In the case above, the binary search would return `I=1', meaning, |
| this OFFSET should be inserted at position 1, and the current |
| position 1 should be pushed further (and before 2). But, `0' |
| overlaps with R. |
| |
| Then we need to check if the I range overlaps the I range itself. |
| E.g., |
| |
| R |
| |---| |
| |---| |---| |-------| ... |--| |
| 0 1 2 N |
| |
| I=1 |
| */ |
| |
| i = VEC_lower_bound (range_s, ranges, &what, range_lessthan); |
| |
| if (i > 0) |
| { |
| struct range *bef = VEC_index (range_s, ranges, i - 1); |
| |
| if (ranges_overlap (bef->offset, bef->length, offset, length)) |
| return 1; |
| } |
| |
| if (i < VEC_length (range_s, ranges)) |
| { |
| struct range *r = VEC_index (range_s, ranges, i); |
| |
| if (ranges_overlap (r->offset, r->length, offset, length)) |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| static struct cmd_list_element *functionlist; |
| |
| /* Note that the fields in this structure are arranged to save a bit |
| of memory. */ |
| |
| struct value |
| { |
| /* Type of value; either not an lval, or one of the various |
| different possible kinds of lval. */ |
| enum lval_type lval; |
| |
| /* Is it modifiable? Only relevant if lval != not_lval. */ |
| unsigned int modifiable : 1; |
| |
| /* If zero, contents of this value are in the contents field. If |
| nonzero, contents are in inferior. If the lval field is lval_memory, |
| the contents are in inferior memory at location.address plus offset. |
| The lval field may also be lval_register. |
| |
| WARNING: This field is used by the code which handles watchpoints |
| (see breakpoint.c) to decide whether a particular value can be |
| watched by hardware watchpoints. If the lazy flag is set for |
| some member of a value chain, it is assumed that this member of |
| the chain doesn't need to be watched as part of watching the |
| value itself. This is how GDB avoids watching the entire struct |
| or array when the user wants to watch a single struct member or |
| array element. If you ever change the way lazy flag is set and |
| reset, be sure to consider this use as well! */ |
| unsigned int lazy : 1; |
| |
| /* If value is a variable, is it initialized or not. */ |
| unsigned int initialized : 1; |
| |
| /* If value is from the stack. If this is set, read_stack will be |
| used instead of read_memory to enable extra caching. */ |
| unsigned int stack : 1; |
| |
| /* If the value has been released. */ |
| unsigned int released : 1; |
| |
| /* Location of value (if lval). */ |
| union |
| { |
| /* If lval == lval_memory, this is the address in the inferior */ |
| CORE_ADDR address; |
| |
| /*If lval == lval_register, the value is from a register. */ |
| struct |
| { |
| /* Register number. */ |
| int regnum; |
| /* Frame ID of "next" frame to which a register value is relative. |
| If the register value is found relative to frame F, then the |
| frame id of F->next will be stored in next_frame_id. */ |
| struct frame_id next_frame_id; |
| } reg; |
| |
| /* Pointer to internal variable. */ |
| struct internalvar *internalvar; |
| |
| /* Pointer to xmethod worker. */ |
| struct xmethod_worker *xm_worker; |
| |
| /* If lval == lval_computed, this is a set of function pointers |
| to use to access and describe the value, and a closure pointer |
| for them to use. */ |
| struct |
| { |
| /* Functions to call. */ |
| const struct lval_funcs *funcs; |
| |
| /* Closure for those functions to use. */ |
| void *closure; |
| } computed; |
| } location; |
| |
| /* Describes offset of a value within lval of a structure in target |
| addressable memory units. Note also the member embedded_offset |
| below. */ |
| LONGEST offset; |
| |
| /* Only used for bitfields; number of bits contained in them. */ |
| LONGEST bitsize; |
| |
| /* Only used for bitfields; position of start of field. For |
| gdbarch_bits_big_endian=0 targets, it is the position of the LSB. For |
| gdbarch_bits_big_endian=1 targets, it is the position of the MSB. */ |
| LONGEST bitpos; |
| |
| /* The number of references to this value. When a value is created, |
| the value chain holds a reference, so REFERENCE_COUNT is 1. If |
| release_value is called, this value is removed from the chain but |
| the caller of release_value now has a reference to this value. |
| The caller must arrange for a call to value_free later. */ |
| int reference_count; |
| |
| /* Only used for bitfields; the containing value. This allows a |
| single read from the target when displaying multiple |
| bitfields. */ |
| struct value *parent; |
| |
| /* Type of the value. */ |
| struct type *type; |
| |
| /* If a value represents a C++ object, then the `type' field gives |
| the object's compile-time type. If the object actually belongs |
| to some class derived from `type', perhaps with other base |
| classes and additional members, then `type' is just a subobject |
| of the real thing, and the full object is probably larger than |
| `type' would suggest. |
| |
| If `type' is a dynamic class (i.e. one with a vtable), then GDB |
| can actually determine the object's run-time type by looking at |
| the run-time type information in the vtable. When this |
| information is available, we may elect to read in the entire |
| object, for several reasons: |
| |
| - When printing the value, the user would probably rather see the |
| full object, not just the limited portion apparent from the |
| compile-time type. |
| |
| - If `type' has virtual base classes, then even printing `type' |
| alone may require reaching outside the `type' portion of the |
| object to wherever the virtual base class has been stored. |
| |
| When we store the entire object, `enclosing_type' is the run-time |
| type -- the complete object -- and `embedded_offset' is the |
| offset of `type' within that larger type, in target addressable memory |
| units. The value_contents() macro takes `embedded_offset' into account, |
| so most GDB code continues to see the `type' portion of the value, just |
| as the inferior would. |
| |
| If `type' is a pointer to an object, then `enclosing_type' is a |
| pointer to the object's run-time type, and `pointed_to_offset' is |
| the offset in target addressable memory units from the full object |
| to the pointed-to object -- that is, the value `embedded_offset' would |
| have if we followed the pointer and fetched the complete object. |
| (I don't really see the point. Why not just determine the |
| run-time type when you indirect, and avoid the special case? The |
| contents don't matter until you indirect anyway.) |
| |
| If we're not doing anything fancy, `enclosing_type' is equal to |
| `type', and `embedded_offset' is zero, so everything works |
| normally. */ |
| struct type *enclosing_type; |
| LONGEST embedded_offset; |
| LONGEST pointed_to_offset; |
| |
| /* Values are stored in a chain, so that they can be deleted easily |
| over calls to the inferior. Values assigned to internal |
| variables, put into the value history or exposed to Python are |
| taken off this list. */ |
| struct value *next; |
| |
| /* Actual contents of the value. Target byte-order. NULL or not |
| valid if lazy is nonzero. */ |
| gdb_byte *contents; |
| |
| /* Unavailable ranges in CONTENTS. We mark unavailable ranges, |
| rather than available, since the common and default case is for a |
| value to be available. This is filled in at value read time. |
| The unavailable ranges are tracked in bits. Note that a contents |
| bit that has been optimized out doesn't really exist in the |
| program, so it can't be marked unavailable either. */ |
| VEC(range_s) *unavailable; |
| |
| /* Likewise, but for optimized out contents (a chunk of the value of |
| a variable that does not actually exist in the program). If LVAL |
| is lval_register, this is a register ($pc, $sp, etc., never a |
| program variable) that has not been saved in the frame. Not |
| saved registers and optimized-out program variables values are |
| treated pretty much the same, except not-saved registers have a |
| different string representation and related error strings. */ |
| VEC(range_s) *optimized_out; |
| }; |
| |
| /* See value.h. */ |
| |
| struct gdbarch * |
| get_value_arch (const struct value *value) |
| { |
| return get_type_arch (value_type (value)); |
| } |
| |
| int |
| value_bits_available (const struct value *value, LONGEST offset, LONGEST length) |
| { |
| gdb_assert (!value->lazy); |
| |
| return !ranges_contain (value->unavailable, offset, length); |
| } |
| |
| int |
| value_bytes_available (const struct value *value, |
| LONGEST offset, LONGEST length) |
| { |
| return value_bits_available (value, |
| offset * TARGET_CHAR_BIT, |
| length * TARGET_CHAR_BIT); |
| } |
| |
| int |
| value_bits_any_optimized_out (const struct value *value, int bit_offset, int bit_length) |
| { |
| gdb_assert (!value->lazy); |
| |
| return ranges_contain (value->optimized_out, bit_offset, bit_length); |
| } |
| |
| int |
| value_entirely_available (struct value *value) |
| { |
| /* We can only tell whether the whole value is available when we try |
| to read it. */ |
| if (value->lazy) |
| value_fetch_lazy (value); |
| |
| if (VEC_empty (range_s, value->unavailable)) |
| return 1; |
| return 0; |
| } |
| |
| /* Returns true if VALUE is entirely covered by RANGES. If the value |
| is lazy, it'll be read now. Note that RANGE is a pointer to |
| pointer because reading the value might change *RANGE. */ |
| |
| static int |
| value_entirely_covered_by_range_vector (struct value *value, |
| VEC(range_s) **ranges) |
| { |
| /* We can only tell whether the whole value is optimized out / |
| unavailable when we try to read it. */ |
| if (value->lazy) |
| value_fetch_lazy (value); |
| |
| if (VEC_length (range_s, *ranges) == 1) |
| { |
| struct range *t = VEC_index (range_s, *ranges, 0); |
| |
| if (t->offset == 0 |
| && t->length == (TARGET_CHAR_BIT |
| * TYPE_LENGTH (value_enclosing_type (value)))) |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| int |
| value_entirely_unavailable (struct value *value) |
| { |
| return value_entirely_covered_by_range_vector (value, &value->unavailable); |
| } |
| |
| int |
| value_entirely_optimized_out (struct value *value) |
| { |
| return value_entirely_covered_by_range_vector (value, &value->optimized_out); |
| } |
| |
| /* Insert into the vector pointed to by VECTORP the bit range starting of |
| OFFSET bits, and extending for the next LENGTH bits. */ |
| |
| static void |
| insert_into_bit_range_vector (VEC(range_s) **vectorp, |
| LONGEST offset, LONGEST length) |
| { |
| range_s newr; |
| int i; |
| |
| /* Insert the range sorted. If there's overlap or the new range |
| would be contiguous with an existing range, merge. */ |
| |
| newr.offset = offset; |
| newr.length = length; |
| |
| /* Do a binary search for the position the given range would be |
| inserted if we only considered the starting OFFSET of ranges. |
| Call that position I. Since we also have LENGTH to care for |
| (this is a range afterall), we need to check if the _previous_ |
| range overlaps the I range. E.g., calling R the new range: |
| |
| #1 - overlaps with previous |
| |
| R |
| |-...-| |
| |---| |---| |------| ... |--| |
| 0 1 2 N |
| |
| I=1 |
| |
| In the case #1 above, the binary search would return `I=1', |
| meaning, this OFFSET should be inserted at position 1, and the |
| current position 1 should be pushed further (and become 2). But, |
| note that `0' overlaps with R, so we want to merge them. |
| |
| A similar consideration needs to be taken if the new range would |
| be contiguous with the previous range: |
| |
| #2 - contiguous with previous |
| |
| R |
| |-...-| |
| |--| |---| |------| ... |--| |
| 0 1 2 N |
| |
| I=1 |
| |
| If there's no overlap with the previous range, as in: |
| |
| #3 - not overlapping and not contiguous |
| |
| R |
| |-...-| |
| |--| |---| |------| ... |--| |
| 0 1 2 N |
| |
| I=1 |
| |
| or if I is 0: |
| |
| #4 - R is the range with lowest offset |
| |
| R |
| |-...-| |
| |--| |---| |------| ... |--| |
| 0 1 2 N |
| |
| I=0 |
| |
| ... we just push the new range to I. |
| |
| All the 4 cases above need to consider that the new range may |
| also overlap several of the ranges that follow, or that R may be |
| contiguous with the following range, and merge. E.g., |
| |
| #5 - overlapping following ranges |
| |
| R |
| |------------------------| |
| |--| |---| |------| ... |--| |
| 0 1 2 N |
| |
| I=0 |
| |
| or: |
| |
| R |
| |-------| |
| |--| |---| |------| ... |--| |
| 0 1 2 N |
| |
| I=1 |
| |
| */ |
| |
| i = VEC_lower_bound (range_s, *vectorp, &newr, range_lessthan); |
| if (i > 0) |
| { |
| struct range *bef = VEC_index (range_s, *vectorp, i - 1); |
| |
| if (ranges_overlap (bef->offset, bef->length, offset, length)) |
| { |
| /* #1 */ |
| ULONGEST l = std::min (bef->offset, offset); |
| ULONGEST h = std::max (bef->offset + bef->length, offset + length); |
| |
| bef->offset = l; |
| bef->length = h - l; |
| i--; |
| } |
| else if (offset == bef->offset + bef->length) |
| { |
| /* #2 */ |
| bef->length += length; |
| i--; |
| } |
| else |
| { |
| /* #3 */ |
| VEC_safe_insert (range_s, *vectorp, i, &newr); |
| } |
| } |
| else |
| { |
| /* #4 */ |
| VEC_safe_insert (range_s, *vectorp, i, &newr); |
| } |
| |
| /* Check whether the ranges following the one we've just added or |
| touched can be folded in (#5 above). */ |
| if (i + 1 < VEC_length (range_s, *vectorp)) |
| { |
| struct range *t; |
| struct range *r; |
| int removed = 0; |
| int next = i + 1; |
| |
| /* Get the range we just touched. */ |
| t = VEC_index (range_s, *vectorp, i); |
| removed = 0; |
| |
| i = next; |
| for (; VEC_iterate (range_s, *vectorp, i, r); i++) |
| if (r->offset <= t->offset + t->length) |
| { |
| ULONGEST l, h; |
| |
| l = std::min (t->offset, r->offset); |
| h = std::max (t->offset + t->length, r->offset + r->length); |
| |
| t->offset = l; |
| t->length = h - l; |
| |
| removed++; |
| } |
| else |
| { |
| /* If we couldn't merge this one, we won't be able to |
| merge following ones either, since the ranges are |
| always sorted by OFFSET. */ |
| break; |
| } |
| |
| if (removed != 0) |
| VEC_block_remove (range_s, *vectorp, next, removed); |
| } |
| } |
| |
| void |
| mark_value_bits_unavailable (struct value *value, |
| LONGEST offset, LONGEST length) |
| { |
| insert_into_bit_range_vector (&value->unavailable, offset, length); |
| } |
| |
| void |
| mark_value_bytes_unavailable (struct value *value, |
| LONGEST offset, LONGEST length) |
| { |
| mark_value_bits_unavailable (value, |
| offset * TARGET_CHAR_BIT, |
| length * TARGET_CHAR_BIT); |
| } |
| |
| /* Find the first range in RANGES that overlaps the range defined by |
| OFFSET and LENGTH, starting at element POS in the RANGES vector, |
| Returns the index into RANGES where such overlapping range was |
| found, or -1 if none was found. */ |
| |
| static int |
| find_first_range_overlap (VEC(range_s) *ranges, int pos, |
| LONGEST offset, LONGEST length) |
| { |
| range_s *r; |
| int i; |
| |
| for (i = pos; VEC_iterate (range_s, ranges, i, r); i++) |
| if (ranges_overlap (r->offset, r->length, offset, length)) |
| return i; |
| |
| return -1; |
| } |
| |
| /* Compare LENGTH_BITS of memory at PTR1 + OFFSET1_BITS with the memory at |
| PTR2 + OFFSET2_BITS. Return 0 if the memory is the same, otherwise |
| return non-zero. |
| |
| It must always be the case that: |
| OFFSET1_BITS % TARGET_CHAR_BIT == OFFSET2_BITS % TARGET_CHAR_BIT |
| |
| It is assumed that memory can be accessed from: |
| PTR + (OFFSET_BITS / TARGET_CHAR_BIT) |
| to: |
| PTR + ((OFFSET_BITS + LENGTH_BITS + TARGET_CHAR_BIT - 1) |
| / TARGET_CHAR_BIT) */ |
| static int |
| memcmp_with_bit_offsets (const gdb_byte *ptr1, size_t offset1_bits, |
| const gdb_byte *ptr2, size_t offset2_bits, |
| size_t length_bits) |
| { |
| gdb_assert (offset1_bits % TARGET_CHAR_BIT |
| == offset2_bits % TARGET_CHAR_BIT); |
| |
| if (offset1_bits % TARGET_CHAR_BIT != 0) |
| { |
| size_t bits; |
| gdb_byte mask, b1, b2; |
| |
| /* The offset from the base pointers PTR1 and PTR2 is not a complete |
| number of bytes. A number of bits up to either the next exact |
| byte boundary, or LENGTH_BITS (which ever is sooner) will be |
| compared. */ |
| bits = TARGET_CHAR_BIT - offset1_bits % TARGET_CHAR_BIT; |
| gdb_assert (bits < sizeof (mask) * TARGET_CHAR_BIT); |
| mask = (1 << bits) - 1; |
| |
| if (length_bits < bits) |
| { |
| mask &= ~(gdb_byte) ((1 << (bits - length_bits)) - 1); |
| bits = length_bits; |
| } |
| |
| /* Now load the two bytes and mask off the bits we care about. */ |
| b1 = *(ptr1 + offset1_bits / TARGET_CHAR_BIT) & mask; |
| b2 = *(ptr2 + offset2_bits / TARGET_CHAR_BIT) & mask; |
| |
| if (b1 != b2) |
| return 1; |
| |
| /* Now update the length and offsets to take account of the bits |
| we've just compared. */ |
| length_bits -= bits; |
| offset1_bits += bits; |
| offset2_bits += bits; |
| } |
| |
| if (length_bits % TARGET_CHAR_BIT != 0) |
| { |
| size_t bits; |
| size_t o1, o2; |
| gdb_byte mask, b1, b2; |
| |
| /* The length is not an exact number of bytes. After the previous |
| IF.. block then the offsets are byte aligned, or the |
| length is zero (in which case this code is not reached). Compare |
| a number of bits at the end of the region, starting from an exact |
| byte boundary. */ |
| bits = length_bits % TARGET_CHAR_BIT; |
| o1 = offset1_bits + length_bits - bits; |
| o2 = offset2_bits + length_bits - bits; |
| |
| gdb_assert (bits < sizeof (mask) * TARGET_CHAR_BIT); |
| mask = ((1 << bits) - 1) << (TARGET_CHAR_BIT - bits); |
| |
| gdb_assert (o1 % TARGET_CHAR_BIT == 0); |
| gdb_assert (o2 % TARGET_CHAR_BIT == 0); |
| |
| b1 = *(ptr1 + o1 / TARGET_CHAR_BIT) & mask; |
| b2 = *(ptr2 + o2 / TARGET_CHAR_BIT) & mask; |
| |
| if (b1 != b2) |
| return 1; |
| |
| length_bits -= bits; |
| } |
| |
| if (length_bits > 0) |
| { |
| /* We've now taken care of any stray "bits" at the start, or end of |
| the region to compare, the remainder can be covered with a simple |
| memcmp. */ |
| gdb_assert (offset1_bits % TARGET_CHAR_BIT == 0); |
| gdb_assert (offset2_bits % TARGET_CHAR_BIT == 0); |
| gdb_assert (length_bits % TARGET_CHAR_BIT == 0); |
| |
| return memcmp (ptr1 + offset1_bits / TARGET_CHAR_BIT, |
| ptr2 + offset2_bits / TARGET_CHAR_BIT, |
| length_bits / TARGET_CHAR_BIT); |
| } |
| |
| /* Length is zero, regions match. */ |
| return 0; |
| } |
| |
| /* Helper struct for find_first_range_overlap_and_match and |
| value_contents_bits_eq. Keep track of which slot of a given ranges |
| vector have we last looked at. */ |
| |
| struct ranges_and_idx |
| { |
| /* The ranges. */ |
| VEC(range_s) *ranges; |
| |
| /* The range we've last found in RANGES. Given ranges are sorted, |
| we can start the next lookup here. */ |
| int idx; |
| }; |
| |
| /* Helper function for value_contents_bits_eq. Compare LENGTH bits of |
| RP1's ranges starting at OFFSET1 bits with LENGTH bits of RP2's |
| ranges starting at OFFSET2 bits. Return true if the ranges match |
| and fill in *L and *H with the overlapping window relative to |
| (both) OFFSET1 or OFFSET2. */ |
| |
| static int |
| find_first_range_overlap_and_match (struct ranges_and_idx *rp1, |
| struct ranges_and_idx *rp2, |
| LONGEST offset1, LONGEST offset2, |
| LONGEST length, ULONGEST *l, ULONGEST *h) |
| { |
| rp1->idx = find_first_range_overlap (rp1->ranges, rp1->idx, |
| offset1, length); |
| rp2->idx = find_first_range_overlap (rp2->ranges, rp2->idx, |
| offset2, length); |
| |
| if (rp1->idx == -1 && rp2->idx == -1) |
| { |
| *l = length; |
| *h = length; |
| return 1; |
| } |
| else if (rp1->idx == -1 || rp2->idx == -1) |
| return 0; |
| else |
| { |
| range_s *r1, *r2; |
| ULONGEST l1, h1; |
| ULONGEST l2, h2; |
| |
| r1 = VEC_index (range_s, rp1->ranges, rp1->idx); |
| r2 = VEC_index (range_s, rp2->ranges, rp2->idx); |
| |
| /* Get the unavailable windows intersected by the incoming |
| ranges. The first and last ranges that overlap the argument |
| range may be wider than said incoming arguments ranges. */ |
| l1 = std::max (offset1, r1->offset); |
| h1 = std::min (offset1 + length, r1->offset + r1->length); |
| |
| l2 = std::max (offset2, r2->offset); |
| h2 = std::min (offset2 + length, offset2 + r2->length); |
| |
| /* Make them relative to the respective start offsets, so we can |
| compare them for equality. */ |
| l1 -= offset1; |
| h1 -= offset1; |
| |
| l2 -= offset2; |
| h2 -= offset2; |
| |
| /* Different ranges, no match. */ |
| if (l1 != l2 || h1 != h2) |
| return 0; |
| |
| *h = h1; |
| *l = l1; |
| return 1; |
| } |
| } |
| |
| /* Helper function for value_contents_eq. The only difference is that |
| this function is bit rather than byte based. |
| |
| Compare LENGTH bits of VAL1's contents starting at OFFSET1 bits |
| with LENGTH bits of VAL2's contents starting at OFFSET2 bits. |
| Return true if the available bits match. */ |
| |
| static bool |
| value_contents_bits_eq (const struct value *val1, int offset1, |
| const struct value *val2, int offset2, |
| int length) |
| { |
| /* Each array element corresponds to a ranges source (unavailable, |
| optimized out). '1' is for VAL1, '2' for VAL2. */ |
| struct ranges_and_idx rp1[2], rp2[2]; |
| |
| /* See function description in value.h. */ |
| gdb_assert (!val1->lazy && !val2->lazy); |
| |
| /* We shouldn't be trying to compare past the end of the values. */ |
| gdb_assert (offset1 + length |
| <= TYPE_LENGTH (val1->enclosing_type) * TARGET_CHAR_BIT); |
| gdb_assert (offset2 + length |
| <= TYPE_LENGTH (val2->enclosing_type) * TARGET_CHAR_BIT); |
| |
| memset (&rp1, 0, sizeof (rp1)); |
| memset (&rp2, 0, sizeof (rp2)); |
| rp1[0].ranges = val1->unavailable; |
| rp2[0].ranges = val2->unavailable; |
| rp1[1].ranges = val1->optimized_out; |
| rp2[1].ranges = val2->optimized_out; |
| |
| while (length > 0) |
| { |
| ULONGEST l = 0, h = 0; /* init for gcc -Wall */ |
| int i; |
| |
| for (i = 0; i < 2; i++) |
| { |
| ULONGEST l_tmp, h_tmp; |
| |
| /* The contents only match equal if the invalid/unavailable |
| contents ranges match as well. */ |
| if (!find_first_range_overlap_and_match (&rp1[i], &rp2[i], |
| offset1, offset2, length, |
| &l_tmp, &h_tmp)) |
| return false; |
| |
| /* We're interested in the lowest/first range found. */ |
| if (i == 0 || l_tmp < l) |
| { |
| l = l_tmp; |
| h = h_tmp; |
| } |
| } |
| |
| /* Compare the available/valid contents. */ |
| if (memcmp_with_bit_offsets (val1->contents, offset1, |
| val2->contents, offset2, l) != 0) |
| return false; |
| |
| length -= h; |
| offset1 += h; |
| offset2 += h; |
| } |
| |
| return true; |
| } |
| |
| bool |
| value_contents_eq (const struct value *val1, LONGEST offset1, |
| const struct value *val2, LONGEST offset2, |
| LONGEST length) |
| { |
| return value_contents_bits_eq (val1, offset1 * TARGET_CHAR_BIT, |
| val2, offset2 * TARGET_CHAR_BIT, |
| length * TARGET_CHAR_BIT); |
| } |
| |
| |
| /* The value-history records all the values printed |
| by print commands during this session. Each chunk |
| records 60 consecutive values. The first chunk on |
| the chain records the most recent values. |
| The total number of values is in value_history_count. */ |
| |
| #define VALUE_HISTORY_CHUNK 60 |
| |
| struct value_history_chunk |
| { |
| struct value_history_chunk *next; |
| struct value *values[VALUE_HISTORY_CHUNK]; |
| }; |
| |
| /* Chain of chunks now in use. */ |
| |
| static struct value_history_chunk *value_history_chain; |
| |
| static int value_history_count; /* Abs number of last entry stored. */ |
| |
| |
| /* List of all value objects currently allocated |
| (except for those released by calls to release_value) |
| This is so they can be freed after each command. */ |
| |
| static struct value *all_values; |
| |
| /* Allocate a lazy value for type TYPE. Its actual content is |
| "lazily" allocated too: the content field of the return value is |
| NULL; it will be allocated when it is fetched from the target. */ |
| |
| struct value * |
| allocate_value_lazy (struct type *type) |
| { |
| struct value *val; |
| |
| /* 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 instead of zero. However, we do not |
| replace the typedef type by the target type, because we want |
| to keep the typedef in order to be able to set the VAL's type |
| description correctly. */ |
| check_typedef (type); |
| |
| val = XCNEW (struct value); |
| val->contents = NULL; |
| val->next = all_values; |
| all_values = val; |
| val->type = type; |
| val->enclosing_type = type; |
| VALUE_LVAL (val) = not_lval; |
| val->location.address = 0; |
| val->offset = 0; |
| val->bitpos = 0; |
| val->bitsize = 0; |
| val->lazy = 1; |
| val->embedded_offset = 0; |
| val->pointed_to_offset = 0; |
| val->modifiable = 1; |
| val->initialized = 1; /* Default to initialized. */ |
| |
| /* Values start out on the all_values chain. */ |
| val->reference_count = 1; |
| |
| return val; |
| } |
| |
| /* The maximum size, in bytes, that GDB will try to allocate for a value. |
| The initial value of 64k was not selected for any specific reason, it is |
| just a reasonable starting point. */ |
| |
| static int max_value_size = 65536; /* 64k bytes */ |
| |
| /* It is critical that the MAX_VALUE_SIZE is at least as big as the size of |
| LONGEST, otherwise GDB will not be able to parse integer values from the |
| CLI; for example if the MAX_VALUE_SIZE could be set to 1 then GDB would |
| be unable to parse "set max-value-size 2". |
| |
| As we want a consistent GDB experience across hosts with different sizes |
| of LONGEST, this arbitrary minimum value was selected, so long as this |
| is bigger than LONGEST on all GDB supported hosts we're fine. */ |
| |
| #define MIN_VALUE_FOR_MAX_VALUE_SIZE 16 |
| gdb_static_assert (sizeof (LONGEST) <= MIN_VALUE_FOR_MAX_VALUE_SIZE); |
| |
| /* Implement the "set max-value-size" command. */ |
| |
| static void |
| set_max_value_size (const char *args, int from_tty, |
| struct cmd_list_element *c) |
| { |
| gdb_assert (max_value_size == -1 || max_value_size >= 0); |
| |
| if (max_value_size > -1 && max_value_size < MIN_VALUE_FOR_MAX_VALUE_SIZE) |
| { |
| max_value_size = MIN_VALUE_FOR_MAX_VALUE_SIZE; |
| error (_("max-value-size set too low, increasing to %d bytes"), |
| max_value_size); |
| } |
| } |
| |
| /* Implement the "show max-value-size" command. */ |
| |
| static void |
| show_max_value_size (struct ui_file *file, int from_tty, |
| struct cmd_list_element *c, const char *value) |
| { |
| if (max_value_size == -1) |
| fprintf_filtered (file, _("Maximum value size is unlimited.\n")); |
| else |
| fprintf_filtered (file, _("Maximum value size is %d bytes.\n"), |
| max_value_size); |
| } |
| |
| /* Called before we attempt to allocate or reallocate a buffer for the |
| contents of a value. TYPE is the type of the value for which we are |
| allocating the buffer. If the buffer is too large (based on the user |
| controllable setting) then throw an error. If this function returns |
| then we should attempt to allocate the buffer. */ |
| |
| static void |
| check_type_length_before_alloc (const struct type *type) |
| { |
| unsigned int length = TYPE_LENGTH (type); |
| |
| if (max_value_size > -1 && length > max_value_size) |
| { |
| if (TYPE_NAME (type) != NULL) |
| error (_("value of type `%s' requires %u bytes, which is more " |
| "than max-value-size"), TYPE_NAME (type), length); |
| else |
| error (_("value requires %u bytes, which is more than " |
| "max-value-size"), length); |
| } |
| } |
| |
| /* Allocate the contents of VAL if it has not been allocated yet. */ |
| |
| static void |
| allocate_value_contents (struct value *val) |
| { |
| if (!val->contents) |
| { |
| check_type_length_before_alloc (val->enclosing_type); |
| val->contents |
| = (gdb_byte *) xzalloc (TYPE_LENGTH (val->enclosing_type)); |
| } |
| } |
| |
| /* Allocate a value and its contents for type TYPE. */ |
| |
| struct value * |
| allocate_value (struct type *type) |
| { |
| struct value *val = allocate_value_lazy (type); |
| |
| allocate_value_contents (val); |
| val->lazy = 0; |
| return val; |
| } |
| |
| /* Allocate a value that has the correct length |
| for COUNT repetitions of type TYPE. */ |
| |
| struct value * |
| allocate_repeat_value (struct type *type, int count) |
| { |
| int low_bound = current_language->string_lower_bound; /* ??? */ |
| /* FIXME-type-allocation: need a way to free this type when we are |
| done with it. */ |
| struct type *array_type |
| = lookup_array_range_type (type, low_bound, count + low_bound - 1); |
| |
| return allocate_value (array_type); |
| } |
| |
| struct value * |
| allocate_computed_value (struct type *type, |
| const struct lval_funcs *funcs, |
| void *closure) |
| { |
| struct value *v = allocate_value_lazy (type); |
| |
| VALUE_LVAL (v) = lval_computed; |
| v->location.computed.funcs = funcs; |
| v->location.computed.closure = closure; |
| |
| return v; |
| } |
| |
| /* Allocate NOT_LVAL value for type TYPE being OPTIMIZED_OUT. */ |
| |
| struct value * |
| allocate_optimized_out_value (struct type *type) |
| { |
| struct value *retval = allocate_value_lazy (type); |
| |
| mark_value_bytes_optimized_out (retval, 0, TYPE_LENGTH (type)); |
| set_value_lazy (retval, 0); |
| return retval; |
| } |
| |
| /* Accessor methods. */ |
| |
| struct value * |
| value_next (const struct value *value) |
| { |
| return value->next; |
| } |
| |
| struct type * |
| value_type (const struct value *value) |
| { |
| return value->type; |
| } |
| void |
| deprecated_set_value_type (struct value *value, struct type *type) |
| { |
| value->type = type; |
| } |
| |
| LONGEST |
| value_offset (const struct value *value) |
| { |
| return value->offset; |
| } |
| void |
| set_value_offset (struct value *value, LONGEST offset) |
| { |
| value->offset = offset; |
| } |
| |
| LONGEST |
| value_bitpos (const struct value *value) |
| { |
| return value->bitpos; |
| } |
| void |
| set_value_bitpos (struct value *value, LONGEST bit) |
| { |
| value->bitpos = bit; |
| } |
| |
| LONGEST |
| value_bitsize (const struct value *value) |
| { |
| return value->bitsize; |
| } |
| void |
| set_value_bitsize (struct value *value, LONGEST bit) |
| { |
| value->bitsize = bit; |
| } |
| |
| struct value * |
| value_parent (const struct value *value) |
| { |
| return value->parent; |
| } |
| |
| /* See value.h. */ |
| |
| void |
| set_value_parent (struct value *value, struct value *parent) |
| { |
| struct value *old = value->parent; |
| |
| value->parent = parent; |
| if (parent != NULL) |
| value_incref (parent); |
| value_free (old); |
| } |
| |
| gdb_byte * |
| value_contents_raw (struct value *value) |
| { |
| struct gdbarch *arch = get_value_arch (value); |
| int unit_size = gdbarch_addressable_memory_unit_size (arch); |
| |
| allocate_value_contents (value); |
| return value->contents + value->embedded_offset * unit_size; |
| } |
| |
| gdb_byte * |
| value_contents_all_raw (struct value *value) |
| { |
| allocate_value_contents (value); |
| return value->contents; |
| } |
| |
| struct type * |
| value_enclosing_type (const struct value *value) |
| { |
| return value->enclosing_type; |
| } |
| |
| /* Look at value.h for description. */ |
| |
| struct type * |
| value_actual_type (struct value *value, int resolve_simple_types, |
| int *real_type_found) |
| { |
| struct value_print_options opts; |
| struct type *result; |
| |
| get_user_print_options (&opts); |
| |
| if (real_type_found) |
| *real_type_found = 0; |
| result = value_type (value); |
| if (opts.objectprint) |
| { |
| /* If result's target type is TYPE_CODE_STRUCT, proceed to |
| fetch its rtti type. */ |
| if ((TYPE_CODE (result) == TYPE_CODE_PTR || TYPE_IS_REFERENCE (result)) |
| && TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (result))) |
| == TYPE_CODE_STRUCT |
| && !value_optimized_out (value)) |
| { |
| struct type *real_type; |
| |
| real_type = value_rtti_indirect_type (value, NULL, NULL, NULL); |
| if (real_type) |
| { |
| if (real_type_found) |
| *real_type_found = 1; |
| result = real_type; |
| } |
| } |
| else if (resolve_simple_types) |
| { |
| if (real_type_found) |
| *real_type_found = 1; |
| result = value_enclosing_type (value); |
| } |
| } |
| |
| return result; |
| } |
| |
| void |
| error_value_optimized_out (void) |
| { |
| error (_("value has been optimized out")); |
| } |
| |
| static void |
| require_not_optimized_out (const struct value *value) |
| { |
| if (!VEC_empty (range_s, value->optimized_out)) |
| { |
| if (value->lval == lval_register) |
| error (_("register has not been saved in frame")); |
| else |
| error_value_optimized_out (); |
| } |
| } |
| |
| static void |
| require_available (const struct value *value) |
| { |
| if (!VEC_empty (range_s, value->unavailable)) |
| throw_error (NOT_AVAILABLE_ERROR, _("value is not available")); |
| } |
| |
| const gdb_byte * |
| value_contents_for_printing (struct value *value) |
| { |
| if (value->lazy) |
| value_fetch_lazy (value); |
| return value->contents; |
| } |
| |
| const gdb_byte * |
| value_contents_for_printing_const (const struct value *value) |
| { |
| gdb_assert (!value->lazy); |
| return value->contents; |
| } |
| |
| const gdb_byte * |
| value_contents_all (struct value *value) |
| { |
| const gdb_byte *result = value_contents_for_printing (value); |
| require_not_optimized_out (value); |
| require_available (value); |
| return result; |
| } |
| |
| /* Copy ranges in SRC_RANGE that overlap [SRC_BIT_OFFSET, |
| SRC_BIT_OFFSET+BIT_LENGTH) ranges into *DST_RANGE, adjusted. */ |
| |
| static void |
| ranges_copy_adjusted (VEC (range_s) **dst_range, int dst_bit_offset, |
| VEC (range_s) *src_range, int src_bit_offset, |
| int bit_length) |
| { |
| range_s *r; |
| int i; |
| |
| for (i = 0; VEC_iterate (range_s, src_range, i, r); i++) |
| { |
| ULONGEST h, l; |
| |
| l = std::max (r->offset, (LONGEST) src_bit_offset); |
| h = std::min (r->offset + r->length, |
| (LONGEST) src_bit_offset + bit_length); |
| |
| if (l < h) |
| insert_into_bit_range_vector (dst_range, |
| dst_bit_offset + (l - src_bit_offset), |
| h - l); |
| } |
| } |
| |
| /* Copy the ranges metadata in SRC that overlaps [SRC_BIT_OFFSET, |
| SRC_BIT_OFFSET+BIT_LENGTH) into DST, adjusted. */ |
| |
| static void |
| value_ranges_copy_adjusted (struct value *dst, int dst_bit_offset, |
| const struct value *src, int src_bit_offset, |
| int bit_length) |
| { |
| ranges_copy_adjusted (&dst->unavailable, dst_bit_offset, |
| src->unavailable, src_bit_offset, |
| bit_length); |
| ranges_copy_adjusted (&dst->optimized_out, dst_bit_offset, |
| src->optimized_out, src_bit_offset, |
| bit_length); |
| } |
| |
| /* Copy LENGTH target addressable memory units of SRC value's (all) contents |
| (value_contents_all) starting at SRC_OFFSET, into DST value's (all) |
| contents, starting at DST_OFFSET. If unavailable contents are |
| being copied from SRC, the corresponding DST contents are marked |
| unavailable accordingly. Neither DST nor SRC may be lazy |
| values. |
| |
| It is assumed the contents of DST in the [DST_OFFSET, |
| DST_OFFSET+LENGTH) range are wholly available. */ |
| |
| void |
| value_contents_copy_raw (struct value *dst, LONGEST dst_offset, |
| struct value *src, LONGEST src_offset, LONGEST length) |
| { |
| LONGEST src_bit_offset, dst_bit_offset, bit_length; |
| struct gdbarch *arch = get_value_arch (src); |
| int unit_size = gdbarch_addressable_memory_unit_size (arch); |
| |
| /* A lazy DST would make that this copy operation useless, since as |
| soon as DST's contents were un-lazied (by a later value_contents |
| call, say), the contents would be overwritten. A lazy SRC would |
| mean we'd be copying garbage. */ |
| gdb_assert (!dst->lazy && !src->lazy); |
| |
| /* The overwritten DST range gets unavailability ORed in, not |
| replaced. Make sure to remember to implement replacing if it |
| turns out actually necessary. */ |
| gdb_assert (value_bytes_available (dst, dst_offset, length)); |
| gdb_assert (!value_bits_any_optimized_out (dst, |
| TARGET_CHAR_BIT * dst_offset, |
| TARGET_CHAR_BIT * length)); |
| |
| /* Copy the data. */ |
| memcpy (value_contents_all_raw (dst) + dst_offset * unit_size, |
| value_contents_all_raw (src) + src_offset * unit_size, |
| length * unit_size); |
| |
| /* Copy the meta-data, adjusted. */ |
| src_bit_offset = src_offset * unit_size * HOST_CHAR_BIT; |
| dst_bit_offset = dst_offset * unit_size * HOST_CHAR_BIT; |
| bit_length = length * unit_size * HOST_CHAR_BIT; |
| |
| value_ranges_copy_adjusted (dst, dst_bit_offset, |
| src, src_bit_offset, |
| bit_length); |
| } |
| |
| /* Copy LENGTH bytes of SRC value's (all) contents |
| (value_contents_all) starting at SRC_OFFSET byte, into DST value's |
| (all) contents, starting at DST_OFFSET. If unavailable contents |
| are being copied from SRC, the corresponding DST contents are |
| marked unavailable accordingly. DST must not be lazy. If SRC is |
| lazy, it will be fetched now. |
| |
| It is assumed the contents of DST in the [DST_OFFSET, |
| DST_OFFSET+LENGTH) range are wholly available. */ |
| |
| void |
| value_contents_copy (struct value *dst, LONGEST dst_offset, |
| struct value *src, LONGEST src_offset, LONGEST length) |
| { |
| if (src->lazy) |
| value_fetch_lazy (src); |
| |
| value_contents_copy_raw (dst, dst_offset, src, src_offset, length); |
| } |
| |
| int |
| value_lazy (const struct value *value) |
| { |
| return value->lazy; |
| } |
| |
| void |
| set_value_lazy (struct value *value, int val) |
| { |
| value->lazy = val; |
| } |
| |
| int |
| value_stack (const struct value *value) |
| { |
| return value->stack; |
| } |
| |
| void |
| set_value_stack (struct value *value, int val) |
| { |
| value->stack = val; |
| } |
| |
| const gdb_byte * |
| value_contents (struct value *value) |
| { |
| const gdb_byte *result = value_contents_writeable (value); |
| require_not_optimized_out (value); |
| require_available (value); |
| return result; |
| } |
| |
| gdb_byte * |
| value_contents_writeable (struct value *value) |
| { |
| if (value->lazy) |
| value_fetch_lazy (value); |
| return value_contents_raw (value); |
| } |
| |
| int |
| value_optimized_out (struct value *value) |
| { |
| /* We can only know if a value is optimized out once we have tried to |
| fetch it. */ |
| if (VEC_empty (range_s, value->optimized_out) && value->lazy) |
| { |
| TRY |
| { |
| value_fetch_lazy (value); |
| } |
| CATCH (ex, RETURN_MASK_ERROR) |
| { |
| /* Fall back to checking value->optimized_out. */ |
| } |
| END_CATCH |
| } |
| |
| return !VEC_empty (range_s, value->optimized_out); |
| } |
| |
| /* Mark contents of VALUE as optimized out, starting at OFFSET bytes, and |
| the following LENGTH bytes. */ |
| |
| void |
| mark_value_bytes_optimized_out (struct value *value, int offset, int length) |
| { |
| mark_value_bits_optimized_out (value, |
| offset * TARGET_CHAR_BIT, |
| length * TARGET_CHAR_BIT); |
| } |
| |
| /* See value.h. */ |
| |
| void |
| mark_value_bits_optimized_out (struct value *value, |
| LONGEST offset, LONGEST length) |
| { |
| insert_into_bit_range_vector (&value->optimized_out, offset, length); |
| } |
| |
| int |
| value_bits_synthetic_pointer (const struct value *value, |
| LONGEST offset, LONGEST length) |
| { |
| if (value->lval != lval_computed |
| || !value->location.computed.funcs->check_synthetic_pointer) |
| return 0; |
| return value->location.computed.funcs->check_synthetic_pointer (value, |
| offset, |
| length); |
| } |
| |
| LONGEST |
| value_embedded_offset (const struct value *value) |
| { |
| return value->embedded_offset; |
| } |
| |
| void |
| set_value_embedded_offset (struct value *value, LONGEST val) |
| { |
| value->embedded_offset = val; |
| } |
| |
| LONGEST |
| value_pointed_to_offset (const struct value *value) |
| { |
| return value->pointed_to_offset; |
| } |
| |
| void |
| set_value_pointed_to_offset (struct value *value, LONGEST val) |
| { |
| value->pointed_to_offset = val; |
| } |
| |
| const struct lval_funcs * |
| value_computed_funcs (const struct value *v) |
| { |
| gdb_assert (value_lval_const (v) == lval_computed); |
| |
| return v->location.computed.funcs; |
| } |
| |
| void * |
| value_computed_closure (const struct value *v) |
| { |
| gdb_assert (v->lval == lval_computed); |
| |
| return v->location.computed.closure; |
| } |
| |
| enum lval_type * |
| deprecated_value_lval_hack (struct value *value) |
| { |
| return &value->lval; |
| } |
| |
| enum lval_type |
| value_lval_const (const struct value *value) |
| { |
| return value->lval; |
| } |
| |
| CORE_ADDR |
| value_address (const struct value *value) |
| { |
| if (value->lval != lval_memory) |
| return 0; |
| if (value->parent != NULL) |
| return value_address (value->parent) + value->offset; |
| if (NULL != TYPE_DATA_LOCATION (value_type (value))) |
| { |
| gdb_assert (PROP_CONST == TYPE_DATA_LOCATION_KIND (value_type (value))); |
| return TYPE_DATA_LOCATION_ADDR (value_type (value)); |
| } |
| |
| return value->location.address + value->offset; |
| } |
| |
| CORE_ADDR |
| value_raw_address (const struct value *value) |
| { |
| if (value->lval != lval_memory) |
| return 0; |
| return value->location.address; |
| } |
| |
| void |
| set_value_address (struct value *value, CORE_ADDR addr) |
| { |
| gdb_assert (value->lval == lval_memory); |
| value->location.address = addr; |
| } |
| |
| struct internalvar ** |
| deprecated_value_internalvar_hack (struct value *value) |
| { |
| return &value->location.internalvar; |
| } |
| |
| struct frame_id * |
| deprecated_value_next_frame_id_hack (struct value *value) |
| { |
| gdb_assert (value->lval == lval_register); |
| return &value->location.reg.next_frame_id; |
| } |
| |
| int * |
| deprecated_value_regnum_hack (struct value *value) |
| { |
| gdb_assert (value->lval == lval_register); |
| return &value->location.reg.regnum; |
| } |
| |
| int |
| deprecated_value_modifiable (const struct value *value) |
| { |
| return value->modifiable; |
| } |
| |
| /* Return a mark in the value chain. All values allocated after the |
| mark is obtained (except for those released) are subject to being freed |
| if a subsequent value_free_to_mark is passed the mark. */ |
| struct value * |
| value_mark (void) |
| { |
| return all_values; |
| } |
| |
| /* Take a reference to VAL. VAL will not be deallocated until all |
| references are released. */ |
| |
| void |
| value_incref (struct value *val) |
| { |
| val->reference_count++; |
| } |
| |
| /* Release a reference to VAL, which was acquired with value_incref. |
| This function is also called to deallocate values from the value |
| chain. */ |
| |
| void |
| value_free (struct value *val) |
| { |
| if (val) |
| { |
| gdb_assert (val->reference_count > 0); |
| val->reference_count--; |
| if (val->reference_count > 0) |
| return; |
| |
| /* If there's an associated parent value, drop our reference to |
| it. */ |
| if (val->parent != NULL) |
| value_free (val->parent); |
| |
| if (VALUE_LVAL (val) == lval_computed) |
| { |
| const struct lval_funcs *funcs = val->location.computed.funcs; |
| |
| if (funcs->free_closure) |
| funcs->free_closure (val); |
| } |
| else if (VALUE_LVAL (val) == lval_xcallable) |
| delete val->location.xm_worker; |
| |
| xfree (val->contents); |
| VEC_free (range_s, val->unavailable); |
| } |
| xfree (val); |
| } |
| |
| /* Free all values allocated since MARK was obtained by value_mark |
| (except for those released). */ |
| void |
| value_free_to_mark (const struct value *mark) |
| { |
| struct value *val; |
| struct value *next; |
| |
| for (val = all_values; val && val != mark; val = next) |
| { |
| next = val->next; |
| val->released = 1; |
| value_free (val); |
| } |
| all_values = val; |
| } |
| |
| /* Free all the values that have been allocated (except for those released). |
| Call after each command, successful or not. |
| In practice this is called before each command, which is sufficient. */ |
| |
| void |
| free_all_values (void) |
| { |
| struct value *val; |
| struct value *next; |
| |
| for (val = all_values; val; val = next) |
| { |
| next = val->next; |
| val->released = 1; |
| value_free (val); |
| } |
| |
| all_values = 0; |
| } |
| |
| /* Frees all the elements in a chain of values. */ |
| |
| void |
| free_value_chain (struct value *v) |
| { |
| struct value *next; |
| |
| for (; v; v = next) |
| { |
| next = value_next (v); |
| value_free (v); |
| } |
| } |
| |
| /* Remove VAL from the chain all_values |
| so it will not be freed automatically. */ |
| |
| void |
| release_value (struct value *val) |
| { |
| struct value *v; |
| |
| if (all_values == val) |
| { |
| all_values = val->next; |
| val->next = NULL; |
| val->released = 1; |
| return; |
| } |
| |
| for (v = all_values; v; v = v->next) |
| { |
| if (v->next == val) |
| { |
| v->next = val->next; |
| val->next = NULL; |
| val->released = 1; |
| break; |
| } |
| } |
| } |
| |
| /* If the value is not already released, release it. |
| If the value is already released, increment its reference count. |
| That is, this function ensures that the value is released from the |
| value chain and that the caller owns a reference to it. */ |
| |
| void |
| release_value_or_incref (struct value *val) |
| { |
| if (val->released) |
| value_incref (val); |
| else |
| release_value (val); |
| } |
| |
| /* Release all values up to mark */ |
| struct value * |
| value_release_to_mark (const struct value *mark) |
| { |
| struct value *val; |
| struct value *next; |
| |
| for (val = next = all_values; next; next = next->next) |
| { |
| if (next->next == mark) |
| { |
| all_values = next->next; |
| next->next = NULL; |
| return val; |
| } |
| next->released = 1; |
| } |
| all_values = 0; |
| return val; |
| } |
| |
| /* Return a copy of the value ARG. |
| It contains the same contents, for same memory address, |
| but it's a different block of storage. */ |
| |
| struct value * |
| value_copy (struct value *arg) |
| { |
| struct type *encl_type = value_enclosing_type (arg); |
| struct value *val; |
| |
| if (value_lazy (arg)) |
| val = allocate_value_lazy (encl_type); |
| else |
| val = allocate_value (encl_type); |
| val->type = arg->type; |
| VALUE_LVAL (val) = VALUE_LVAL (arg); |
| val->location = arg->location; |
| val->offset = arg->offset; |
| val->bitpos = arg->bitpos; |
| val->bitsize = arg->bitsize; |
| val->lazy = arg->lazy; |
| val->embedded_offset = value_embedded_offset (arg); |
| val->pointed_to_offset = arg->pointed_to_offset; |
| val->modifiable = arg->modifiable; |
| if (!value_lazy (val)) |
| { |
| memcpy (value_contents_all_raw (val), value_contents_all_raw (arg), |
| TYPE_LENGTH (value_enclosing_type (arg))); |
| |
| } |
| val->unavailable = VEC_copy (range_s, arg->unavailable); |
| val->optimized_out = VEC_copy (range_s, arg->optimized_out); |
| set_value_parent (val, arg->parent); |
| if (VALUE_LVAL (val) == lval_computed) |
| { |
| const struct lval_funcs *funcs = val->location.computed.funcs; |
| |
| if (funcs->copy_closure) |
| val->location.computed.closure = funcs->copy_closure (val); |
| } |
| return val; |
| } |
| |
| /* Return a "const" and/or "volatile" qualified version of the value V. |
| If CNST is true, then the returned value will be qualified with |
| "const". |
| if VOLTL is true, then the returned value will be qualified with |
| "volatile". */ |
| |
| struct value * |
| make_cv_value (int cnst, int voltl, struct value *v) |
| { |
| struct type *val_type = value_type (v); |
| struct type *enclosing_type = value_enclosing_type (v); |
| struct value *cv_val = value_copy (v); |
| |
| deprecated_set_value_type (cv_val, |
| make_cv_type (cnst, voltl, val_type, NULL)); |
| set_value_enclosing_type (cv_val, |
| make_cv_type (cnst, voltl, enclosing_type, NULL)); |
| |
| return cv_val; |
| } |
| |
| /* Return a version of ARG that is non-lvalue. */ |
| |
| struct value * |
| value_non_lval (struct value *arg) |
| { |
| if (VALUE_LVAL (arg) != not_lval) |
| { |
| struct type *enc_type = value_enclosing_type (arg); |
| struct value *val = allocate_value (enc_type); |
| |
| memcpy (value_contents_all_raw (val), value_contents_all (arg), |
| TYPE_LENGTH (enc_type)); |
| val->type = arg->type; |
| set_value_embedded_offset (val, value_embedded_offset (arg)); |
| set_value_pointed_to_offset (val, value_pointed_to_offset (arg)); |
| return val; |
| } |
| return arg; |
| } |
| |
| /* Write contents of V at ADDR and set its lval type to be LVAL_MEMORY. */ |
| |
| void |
| value_force_lval (struct value *v, CORE_ADDR addr) |
| { |
| gdb_assert (VALUE_LVAL (v) == not_lval); |
| |
| write_memory (addr, value_contents_raw (v), TYPE_LENGTH (value_type (v))); |
| v->lval = lval_memory; |
| v->location.address = addr; |
| } |
| |
| void |
| set_value_component_location (struct value *component, |
| const struct value *whole) |
| { |
| struct type *type; |
| |
| gdb_assert (whole->lval != lval_xcallable); |
| |
| if (whole->lval == lval_internalvar) |
| VALUE_LVAL (component) = lval_internalvar_component; |
| else |
| VALUE_LVAL (component) = whole->lval; |
| |
| component->location = whole->location; |
| if (whole->lval == lval_computed) |
| { |
| const struct lval_funcs *funcs = whole->location.computed.funcs; |
| |
| if (funcs->copy_closure) |
| component->location.computed.closure = funcs->copy_closure (whole); |
| } |
| |
| /* If type has a dynamic resolved location property |
| update it's value address. */ |
| type = value_type (whole); |
| if (NULL != TYPE_DATA_LOCATION (type) |
| && TYPE_DATA_LOCATION_KIND (type) == PROP_CONST) |
| set_value_address (component, TYPE_DATA_LOCATION_ADDR (type)); |
| } |
| |
| /* Access to the value history. */ |
| |
| /* Record a new value in the value history. |
| Returns the absolute history index of the entry. */ |
| |
| int |
| record_latest_value (struct value *val) |
| { |
| int i; |
| |
| /* We don't want this value to have anything to do with the inferior anymore. |
| In particular, "set $1 = 50" should not affect the variable from which |
| the value was taken, and fast watchpoints should be able to assume that |
| a value on the value history never changes. */ |
| if (value_lazy (val)) |
| value_fetch_lazy (val); |
| /* We preserve VALUE_LVAL so that the user can find out where it was fetched |
| from. This is a bit dubious, because then *&$1 does not just return $1 |
| but the current contents of that location. c'est la vie... */ |
| val->modifiable = 0; |
| |
| /* The value may have already been released, in which case we're adding a |
| new reference for its entry in the history. That is why we call |
| release_value_or_incref here instead of release_value. */ |
| release_value_or_incref (val); |
| |
| /* Here we treat value_history_count as origin-zero |
| and applying to the value being stored now. */ |
| |
| i = value_history_count % VALUE_HISTORY_CHUNK; |
| if (i == 0) |
| { |
| struct value_history_chunk *newobj = XCNEW (struct value_history_chunk); |
| |
| newobj->next = value_history_chain; |
| value_history_chain = newobj; |
| } |
| |
| value_history_chain->values[i] = val; |
| |
| /* Now we regard value_history_count as origin-one |
| and applying to the value just stored. */ |
| |
| return ++value_history_count; |
| } |
| |
| /* Return a copy of the value in the history with sequence number NUM. */ |
| |
| struct value * |
| access_value_history (int num) |
| { |
| struct value_history_chunk *chunk; |
| int i; |
| int absnum = num; |
| |
| if (absnum <= 0) |
| absnum += value_history_count; |
| |
| if (absnum <= 0) |
| { |
| if (num == 0) |
| error (_("The history is empty.")); |
| else if (num == 1) |
| error (_("There is only one value in the history.")); |
| else |
| error (_("History does not go back to $$%d."), -num); |
| } |
| if (absnum > value_history_count) |
| error (_("History has not yet reached $%d."), absnum); |
| |
| absnum--; |
| |
| /* Now absnum is always absolute and origin zero. */ |
| |
| chunk = value_history_chain; |
| for (i = (value_history_count - 1) / VALUE_HISTORY_CHUNK |
| - absnum / VALUE_HISTORY_CHUNK; |
| i > 0; i--) |
| chunk = chunk->next; |
| |
| return value_copy (chunk->values[absnum % VALUE_HISTORY_CHUNK]); |
| } |
| |
| static void |
| show_values (const char *num_exp, int from_tty) |
| { |
| int i; |
| struct value *val; |
| static int num = 1; |
| |
| if (num_exp) |
| { |
| /* "show values +" should print from the stored position. |
| "show values <exp>" should print around value number <exp>. */ |
| if (num_exp[0] != '+' || num_exp[1] != '\0') |
| num = parse_and_eval_long (num_exp) - 5; |
| } |
| else |
| { |
| /* "show values" means print the last 10 values. */ |
| num = value_history_count - 9; |
| } |
| |
| if (num <= 0) |
| num = 1; |
| |
| for (i = num; i < num + 10 && i <= value_history_count; i++) |
| { |
| struct value_print_options opts; |
| |
| val = access_value_history (i); |
| printf_filtered (("$%d = "), i); |
| get_user_print_options (&opts); |
| value_print (val, gdb_stdout, &opts); |
| printf_filtered (("\n")); |
| } |
| |
| /* The next "show values +" should start after what we just printed. */ |
| num += 10; |
| |
| /* Hitting just return after this command should do the same thing as |
| "show values +". If num_exp is null, this is unnecessary, since |
| "show values +" is not useful after "show values". */ |
| if (from_tty && num_exp) |
| set_repeat_arguments ("+"); |
| } |
| |
| enum internalvar_kind |
| { |
| /* The internal variable is empty. */ |
| INTERNALVAR_VOID, |
| |
| /* The value of the internal variable is provided directly as |
| a GDB value object. */ |
| INTERNALVAR_VALUE, |
| |
| /* A fresh value is computed via a call-back routine on every |
| access to the internal variable. */ |
| INTERNALVAR_MAKE_VALUE, |
| |
| /* The internal variable holds a GDB internal convenience function. */ |
| INTERNALVAR_FUNCTION, |
| |
| /* The variable holds an integer value. */ |
| INTERNALVAR_INTEGER, |
| |
| /* The variable holds a GDB-provided string. */ |
| INTERNALVAR_STRING, |
| }; |
| |
| union internalvar_data |
| { |
| /* A value object used with INTERNALVAR_VALUE. */ |
| struct value *value; |
| |
| /* The call-back routine used with INTERNALVAR_MAKE_VALUE. */ |
| struct |
| { |
| /* The functions to call. */ |
| const struct internalvar_funcs *functions; |
| |
| /* The function's user-data. */ |
| void *data; |
| } make_value; |
| |
| /* The internal function used with INTERNALVAR_FUNCTION. */ |
| struct |
| { |
| struct internal_function *function; |
| /* True if this is the canonical name for the function. */ |
| int canonical; |
| } fn; |
| |
| /* An integer value used with INTERNALVAR_INTEGER. */ |
| struct |
| { |
| /* If type is non-NULL, it will be used as the type to generate |
| a value for this internal variable. If type is NULL, a default |
| integer type for the architecture is used. */ |
| struct type *type; |
| LONGEST val; |
| } integer; |
| |
| /* A string value used with INTERNALVAR_STRING. */ |
| char *string; |
| }; |
| |
| /* Internal variables. These are variables within the debugger |
| that hold values assigned by debugger commands. |
| The user refers to them with a '$' prefix |
| that does not appear in the variable names stored internally. */ |
| |
| struct internalvar |
| { |
| struct internalvar *next; |
| char *name; |
| |
| /* We support various different kinds of content of an internal variable. |
| enum internalvar_kind specifies the kind, and union internalvar_data |
| provides the data associated with this particular kind. */ |
| |
| enum internalvar_kind kind; |
| |
| union internalvar_data u; |
| }; |
| |
| static struct internalvar *internalvars; |
| |
| /* If the variable does not already exist create it and give it the |
| value given. If no value is given then the default is zero. */ |
| static void |
| init_if_undefined_command (const char* args, int from_tty) |
| { |
| struct internalvar* intvar; |
| |
| /* Parse the expression - this is taken from set_command(). */ |
| expression_up expr = parse_expression (args); |
| |
| /* Validate the expression. |
| Was the expression an assignment? |
| Or even an expression at all? */ |
| if (expr->nelts == 0 || expr->elts[0].opcode != BINOP_ASSIGN) |
| error (_("Init-if-undefined requires an assignment expression.")); |
| |
| /* Extract the variable from the parsed expression. |
| In the case of an assign the lvalue will be in elts[1] and elts[2]. */ |
| if (expr->elts[1].opcode != OP_INTERNALVAR) |
| error (_("The first parameter to init-if-undefined " |
| "should be a GDB variable.")); |
| intvar = expr->elts[2].internalvar; |
| |
| /* Only evaluate the expression if the lvalue is void. |
| This may still fail if the expresssion is invalid. */ |
| if (intvar->kind == INTERNALVAR_VOID) |
| evaluate_expression (expr.get ()); |
| } |
| |
| |
| /* Look up an internal variable with name NAME. NAME should not |
| normally include a dollar sign. |
| |
| If the specified internal variable does not exist, |
| the return value is NULL. */ |
| |
| struct internalvar * |
| lookup_only_internalvar (const char *name) |
| { |
| struct internalvar *var; |
| |
| for (var = internalvars; var; var = var->next) |
| if (strcmp (var->name, name) == 0) |
| return var; |
| |
| return NULL; |
| } |
| |
| /* Complete NAME by comparing it to the names of internal |
| variables. */ |
| |
| void |
| complete_internalvar (completion_tracker &tracker, const char *name) |
| { |
| struct internalvar *var; |
| int len; |
| |
| len = strlen (name); |
| |
| for (var = internalvars; var; var = var->next) |
| if (strncmp (var->name, name, len) == 0) |
| { |
| gdb::unique_xmalloc_ptr<char> copy (xstrdup (var->name)); |
| |
| tracker.add_completion (std::move (copy)); |
| } |
| } |
| |
| /* Create an internal variable with name NAME and with a void value. |
| NAME should not normally include a dollar sign. */ |
| |
| struct internalvar * |
| create_internalvar (const char *name) |
| { |
| struct internalvar *var = XNEW (struct internalvar); |
| |
| var->name = concat (name, (char *)NULL); |
| var->kind = INTERNALVAR_VOID; |
| var->next = internalvars; |
| internalvars = var; |
| return var; |
| } |
| |
| /* Create an internal variable with name NAME and register FUN as the |
| function that value_of_internalvar uses to create a value whenever |
| this variable is referenced. NAME should not normally include a |
| dollar sign. DATA is passed uninterpreted to FUN when it is |
| called. CLEANUP, if not NULL, is called when the internal variable |
| is destroyed. It is passed DATA as its only argument. */ |
| |
| struct internalvar * |
| create_internalvar_type_lazy (const char *name, |
| const struct internalvar_funcs *funcs, |
| void *data) |
| { |
| struct internalvar *var = create_internalvar (name); |
| |
| var->kind = INTERNALVAR_MAKE_VALUE; |
| var->u.make_value.functions = funcs; |
| var->u.make_value.data = data; |
| return var; |
| } |
| |
| /* See documentation in value.h. */ |
| |
| int |
| compile_internalvar_to_ax (struct internalvar *var, |
| struct agent_expr *expr, |
| struct axs_value *value) |
| { |
| if (var->kind != INTERNALVAR_MAKE_VALUE |
| || var->u.make_value.functions->compile_to_ax == NULL) |
| return 0; |
| |
| var->u.make_value.functions->compile_to_ax (var, expr, value, |
| var->u.make_value.data); |
| return 1; |
| } |
| |
| /* Look up an internal variable with name NAME. NAME should not |
| normally include a dollar sign. |
| |
| If the specified internal variable does not exist, |
| one is created, with a void value. */ |
| |
| struct internalvar * |
| lookup_internalvar (const char *name) |
| { |
| struct internalvar *var; |
| |
| var = lookup_only_internalvar (name); |
| if (var) |
| return var; |
| |
| return create_internalvar (name); |
| } |
| |
| /* Return current value of internal variable VAR. For variables that |
| are not inherently typed, use a value type appropriate for GDBARCH. */ |
| |
| struct value * |
| value_of_internalvar (struct gdbarch *gdbarch, struct internalvar *var) |
| { |
| struct value *val; |
| struct trace_state_variable *tsv; |
| |
| /* If there is a trace state variable of the same name, assume that |
| is what we really want to see. */ |
| tsv = find_trace_state_variable (var->name); |
| if (tsv) |
| { |
| tsv->value_known = target_get_trace_state_variable_value (tsv->number, |
| &(tsv->value)); |
| if (tsv->value_known) |
| val = value_from_longest (builtin_type (gdbarch)->builtin_int64, |
| tsv->value); |
| else |
| val = allocate_value (builtin_type (gdbarch)->builtin_void); |
| return val; |
| } |
| |
| switch (var->kind) |
| { |
| case INTERNALVAR_VOID: |
| val = allocate_value (builtin_type (gdbarch)->builtin_void); |
| break; |
| |
| case INTERNALVAR_FUNCTION: |
| val = allocate_value (builtin_type (gdbarch)->internal_fn); |
| break; |
| |
| case INTERNALVAR_INTEGER: |
| if (!var->u.integer.type) |
| val = value_from_longest (builtin_type (gdbarch)->builtin_int, |
| var->u.integer.val); |
| else |
| val = value_from_longest (var->u.integer.type, var->u.integer.val); |
| break; |
| |
| case INTERNALVAR_STRING: |
| val = value_cstring (var->u.string, strlen (var->u.string), |
| builtin_type (gdbarch)->builtin_char); |
| break; |
| |
| case INTERNALVAR_VALUE: |
| val = value_copy (var->u.value); |
| if (value_lazy (val)) |
| value_fetch_lazy (val); |
| break; |
| |
| case INTERNALVAR_MAKE_VALUE: |
| val = (*var->u.make_value.functions->make_value) (gdbarch, var, |
| var->u.make_value.data); |
| break; |
| |
| default: |
| internal_error (__FILE__, __LINE__, _("bad kind")); |
| } |
| |
| /* Change the VALUE_LVAL to lval_internalvar so that future operations |
| on this value go back to affect the original internal variable. |
| |
| Do not do this for INTERNALVAR_MAKE_VALUE variables, as those have |
| no underlying modifyable state in the internal variable. |
| |
| Likewise, if the variable's value is a computed lvalue, we want |
| references to it to produce another computed lvalue, where |
| references and assignments actually operate through the |
| computed value's functions. |
| |
| This means that internal variables with computed values |
| behave a little differently from other internal variables: |
| assignments to them don't just replace the previous value |
| altogether. At the moment, this seems like the behavior we |
| want. */ |
| |
| if (var->kind != INTERNALVAR_MAKE_VALUE |
| && val->lval != lval_computed) |
| { |
| VALUE_LVAL (val) = lval_internalvar; |
| VALUE_INTERNALVAR (val) = var; |
| } |
| |
| return val; |
| } |
| |
| int |
| get_internalvar_integer (struct internalvar *var, LONGEST *result) |
| { |
| if (var->kind == INTERNALVAR_INTEGER) |
| { |
| *result = var->u.integer.val; |
| return 1; |
| } |
| |
| if (var->kind == INTERNALVAR_VALUE) |
| { |
| struct type *type = check_typedef (value_type (var->u.value)); |
| |
| if (TYPE_CODE (type) == TYPE_CODE_INT) |
| { |
| *result = value_as_long (var->u.value); |
| return 1; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int |
| get_internalvar_function (struct internalvar *var, |
| struct internal_function **result) |
| { |
| switch (var->kind) |
| { |
| case INTERNALVAR_FUNCTION: |
| *result = var->u.fn.function; |
| return 1; |
| |
| default: |
| return 0; |
| } |
| } |
| |
| void |
| set_internalvar_component (struct internalvar *var, |
| LONGEST offset, LONGEST bitpos, |
| LONGEST bitsize, struct value *newval) |
| { |
| gdb_byte *addr; |
| struct gdbarch *arch; |
| int unit_size; |
| |
| switch (var->kind) |
| { |
| case INTERNALVAR_VALUE: |
| addr = value_contents_writeable (var->u.value); |
| arch = get_value_arch (var->u.value); |
| unit_size = gdbarch_addressable_memory_unit_size (arch); |
| |
| if (bitsize) |
| modify_field (value_type (var->u.value), addr + offset, |
| value_as_long (newval), bitpos, bitsize); |
| else |
| memcpy (addr + offset * unit_size, value_contents (newval), |
| TYPE_LENGTH (value_type (newval))); |
| break; |
| |
| default: |
| /* We can never get a component of any other kind. */ |
| internal_error (__FILE__, __LINE__, _("set_internalvar_component")); |
| } |
| } |
| |
| void |
| set_internalvar (struct internalvar *var, struct value *val) |
| { |
| enum internalvar_kind new_kind; |
| union internalvar_data new_data = { 0 }; |
| |
| if (var->kind == INTERNALVAR_FUNCTION && var->u.fn.canonical) |
| error (_("Cannot overwrite convenience function %s"), var->name); |
| |
| /* Prepare new contents. */ |
| switch (TYPE_CODE (check_typedef (value_type (val)))) |
| { |
| case TYPE_CODE_VOID: |
| new_kind = INTERNALVAR_VOID; |
| break; |
| |
| case TYPE_CODE_INTERNAL_FUNCTION: |
| gdb_assert (VALUE_LVAL (val) == lval_internalvar); |
| new_kind = INTERNALVAR_FUNCTION; |
| get_internalvar_function (VALUE_INTERNALVAR (val), |
| &new_data.fn.function); |
| /* Copies created here are never canonical. */ |
| break; |
| |
| default: |
| new_kind = INTERNALVAR_VALUE; |
| new_data.value = value_copy (val); |
| new_data.value->modifiable = 1; |
| |
| /* Force the value to be fetched from the target now, to avoid problems |
| later when this internalvar is referenced and the target is gone or |
| has changed. */ |
| if (value_lazy (new_data.value)) |
| value_fetch_lazy (new_data.value); |
| |
| /* Release the value from the value chain to prevent it from being |
| deleted by free_all_values. From here on this function should not |
| call error () until new_data is installed into the var->u to avoid |
| leaking memory. */ |
| release_value (new_data.value); |
| |
| /* Internal variables which are created from values with a dynamic |
| location don't need the location property of the origin anymore. |
| The resolved dynamic location is used prior then any other address |
| when accessing the value. |
| If we keep it, we would still refer to the origin value. |
| Remove the location property in case it exist. */ |
| remove_dyn_prop (DYN_PROP_DATA_LOCATION, value_type (new_data.value)); |
| |
| break; |
| } |
| |
| /* Clean up old contents. */ |
| clear_internalvar (var); |
| |
| /* Switch over. */ |
| var->kind = new_kind; |
| var->u = new_data; |
| /* End code which must not call error(). */ |
| } |
| |
| void |
| set_internalvar_integer (struct internalvar *var, LONGEST l) |
| { |
| /* Clean up old contents. */ |
| clear_internalvar (var); |
| |
| var->kind = INTERNALVAR_INTEGER; |
| var->u.integer.type = NULL; |
| var->u.integer.val = l; |
| } |
| |
| void |
| set_internalvar_string (struct internalvar *var, const char *string) |
| { |
| /* Clean up old contents. */ |
| clear_internalvar (var); |
| |
| var->kind = INTERNALVAR_STRING; |
| var->u.string = xstrdup (string); |
| } |
| |
| static void |
| set_internalvar_function (struct internalvar *var, struct internal_function *f) |
| { |
| /* Clean up old contents. */ |
| clear_internalvar (var); |
| |
| var->kind = INTERNALVAR_FUNCTION; |
| var->u.fn.function = f; |
| var->u.fn.canonical = 1; |
| /* Variables installed here are always the canonical version. */ |
| } |
| |
| void |
| clear_internalvar (struct internalvar *var) |
| { |
| /* Clean up old contents. */ |
| switch (var->kind) |
| { |
| case INTERNALVAR_VALUE: |
| value_free (var->u.value); |
| break; |
| |
| case INTERNALVAR_STRING: |
| xfree (var->u.string); |
| break; |
| |
| case INTERNALVAR_MAKE_VALUE: |
| if (var->u.make_value.functions->destroy != NULL) |
| var->u.make_value.functions->destroy (var->u.make_value.data); |
| break; |
| |
| default: |
| break; |
| } |
| |
| /* Reset to void kind. */ |
| var->kind = INTERNALVAR_VOID; |
| } |
| |
| char * |
| internalvar_name (const struct internalvar *var) |
| { |
| return var->name; |
| } |
| |
| static struct internal_function * |
| create_internal_function (const char *name, |
| internal_function_fn handler, void *cookie) |
| { |
| struct internal_function *ifn = XNEW (struct internal_function); |
| |
| ifn->name = xstrdup (name); |
| ifn->handler = handler; |
| ifn->cookie = cookie; |
| return ifn; |
| } |
| |
| char * |
| value_internal_function_name (struct value *val) |
| { |
| struct internal_function *ifn; |
| int result; |
| |
| gdb_assert (VALUE_LVAL (val) == lval_internalvar); |
| result = get_internalvar_function (VALUE_INTERNALVAR (val), &ifn); |
| gdb_assert (result); |
| |
| return ifn->name; |
| } |
| |
| struct value * |
| call_internal_function (struct gdbarch *gdbarch, |
| const struct language_defn *language, |
| struct value *func, int argc, struct value **argv) |
| { |
| struct internal_function *ifn; |
| int result; |
| |
| gdb_assert (VALUE_LVAL (func) == lval_internalvar); |
| result = get_internalvar_function (VALUE_INTERNALVAR (func), &ifn); |
| gdb_assert (result); |
| |
| return (*ifn->handler) (gdbarch, language, ifn->cookie, argc, argv); |
| } |
| |
| /* The 'function' command. This does nothing -- it is just a |
| placeholder to let "help function NAME" work. This is also used as |
| the implementation of the sub-command that is created when |
| registering an internal function. */ |
| static void |
| function_command (const char *command, int from_tty) |
| { |
| /* Do nothing. */ |
| } |
| |
| /* Clean up if an internal function's command is destroyed. */ |
| static void |
| function_destroyer (struct cmd_list_element *self, void *ignore) |
| { |
| xfree ((char *) self->name); |
| xfree ((char *) self->doc); |
| } |
| |
| /* Add a new internal function. NAME is the name of the function; DOC |
| is a documentation string describing the function. HANDLER is |
| called when the function is invoked. COOKIE is an arbitrary |
| pointer which is passed to HANDLER and is intended for "user |
| data". */ |
| void |
| add_internal_function (const char *name, const char *doc, |
| internal_function_fn handler, void *cookie) |
| { |
| struct cmd_list_element *cmd; |
| struct internal_function *ifn; |
| struct internalvar *var = lookup_internalvar (name); |
| |
| ifn = create_internal_function (name, handler, cookie); |
| set_internalvar_function (var, ifn); |
| |
| cmd = add_cmd (xstrdup (name), no_class, function_command, (char *) doc, |
| &functionlist); |
| cmd->destroyer = function_destroyer; |
| } |
| |
| /* Update VALUE before discarding OBJFILE. COPIED_TYPES is used to |
| prevent cycles / duplicates. */ |
| |
| void |
| preserve_one_value (struct value *value, struct objfile *objfile, |
| htab_t copied_types) |
| { |
| if (TYPE_OBJFILE (value->type) == objfile) |
| value->type = copy_type_recursive (objfile, value->type, copied_types); |
| |
| if (TYPE_OBJFILE (value->enclosing_type) == objfile) |
| value->enclosing_type = copy_type_recursive (objfile, |
| value->enclosing_type, |
| copied_types); |
| } |
| |
| /* Likewise for internal variable VAR. */ |
| |
| static void |
| preserve_one_internalvar (struct internalvar *var, struct objfile *objfile, |
| htab_t copied_types) |
| { |
| switch (var->kind) |
| { |
| case INTERNALVAR_INTEGER: |
| if (var->u.integer.type && TYPE_OBJFILE (var->u.integer.type) == objfile) |
| var->u.integer.type |
| = copy_type_recursive (objfile, var->u.integer.type, copied_types); |
| break; |
| |
| case INTERNALVAR_VALUE: |
| preserve_one_value (var->u.value, objfile, copied_types); |
| break; |
| } |
| } |
| |
| /* Update the internal variables and value history when OBJFILE is |
| discarded; we must copy the types out of the objfile. New global types |
| will be created for every convenience variable which currently points to |
| this objfile's types, and the convenience variables will be adjusted to |
| use the new global types. */ |
| |
| void |
| preserve_values (struct objfile *objfile) |
| { |
| htab_t copied_types; |
| struct value_history_chunk *cur; |
| struct internalvar *var; |
| int i; |
| |
| /* Create the hash table. We allocate on the objfile's obstack, since |
| it is soon to be deleted. */ |
| copied_types = create_copied_types_hash (objfile); |
| |
| for (cur = value_history_chain; cur; cur = cur->next) |
| for (i = 0; i < VALUE_HISTORY_CHUNK; i++) |
| if (cur->values[i]) |
| preserve_one_value (cur->values[i], objfile, copied_types); |
| |
| for (var = internalvars; var; var = var->next) |
| preserve_one_internalvar (var, objfile, copied_types); |
| |
| preserve_ext_lang_values (objfile, copied_types); |
| |
| htab_delete (copied_types); |
| } |
| |
| static void |
| show_convenience (const char *ignore, int from_tty) |
| { |
| struct gdbarch *gdbarch = get_current_arch (); |
| struct internalvar *var; |
| int varseen = 0; |
| struct value_print_options opts; |
| |
| get_user_print_options (&opts); |
| for (var = internalvars; var; var = var->next) |
| { |
| |
| if (!varseen) |
| { |
| varseen = 1; |
| } |
| printf_filtered (("$%s = "), var->name); |
| |
| TRY |
| { |
| struct value *val; |
| |
| val = value_of_internalvar (gdbarch, var); |
| value_print (val, gdb_stdout, &opts); |
| } |
| CATCH (ex, RETURN_MASK_ERROR) |
| { |
| fprintf_filtered (gdb_stdout, _("<error: %s>"), ex.message); |
| } |
| END_CATCH |
| |
| printf_filtered (("\n")); |
| } |
| if (!varseen) |
| { |
| /* This text does not mention convenience functions on purpose. |
| The user can't create them except via Python, and if Python support |
| is installed this message will never be printed ($_streq will |
| exist). */ |
| printf_unfiltered (_("No debugger convenience variables now defined.\n" |
| "Convenience variables have " |
| "names starting with \"$\";\n" |
| "use \"set\" as in \"set " |
| "$foo = 5\" to define them.\n")); |
| } |
| } |
| |
| |
| /* See value.h. */ |
| |
| struct value * |
| value_from_xmethod (xmethod_worker_up &&worker) |
| { |
| struct value *v; |
| |
| v = allocate_value (builtin_type (target_gdbarch ())->xmethod); |
| v->lval = lval_xcallable; |
| v->location.xm_worker = worker.release (); |
| v->modifiable = 0; |
| |
| return v; |
| } |
| |
| /* Return the type of the result of TYPE_CODE_XMETHOD value METHOD. */ |
| |
| struct type * |
| result_type_of_xmethod (struct value *method, int argc, struct value **argv) |
| { |
| gdb_assert (TYPE_CODE (value_type (method)) == TYPE_CODE_XMETHOD |
| && method->lval == lval_xcallable && argc > 0); |
| |
| return method->location.xm_worker->get_result_type |
| (argv[0], argv + 1, argc - 1); |
| } |
| |
| /* Call the xmethod corresponding to the TYPE_CODE_XMETHOD value METHOD. */ |
| |
| struct value * |
| call_xmethod (struct value *method, int argc, struct value **argv) |
| { |
| gdb_assert (TYPE_CODE (value_type (method)) == TYPE_CODE_XMETHOD |
| && method->lval == lval_xcallable && argc > 0); |
| |
| return method->location.xm_worker->invoke (argv[0], argv + 1, argc - 1); |
| } |
| |
| /* Extract a value as a C number (either long or double). |
| Knows how to convert fixed values to double, or |
| floating values to long. |
| Does not deallocate the value. */ |
| |
| LONGEST |
| value_as_long (struct value *val) |
| { |
| /* This coerces arrays and functions, which is necessary (e.g. |
| in disassemble_command). It also dereferences references, which |
| I suspect is the most logical thing to do. */ |
| val = coerce_array (val); |
| return unpack_long (value_type (val), value_contents (val)); |
| } |
| |
| /* Extract a value as a C pointer. Does not deallocate the value. |
| Note that val's type may not actually be a pointer; value_as_long |
| handles all the cases. */ |
| CORE_ADDR |
| value_as_address (struct value *val) |
| { |
| struct gdbarch *gdbarch = get_type_arch (value_type (val)); |
| |
| /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure |
| whether we want this to be true eventually. */ |
| #if 0 |
| /* gdbarch_addr_bits_remove is wrong if we are being called for a |
| non-address (e.g. argument to "signal", "info break", etc.), or |
| for pointers to char, in which the low bits *are* significant. */ |
| return gdbarch_addr_bits_remove (gdbarch, value_as_long (val)); |
| #else |
| |
| /* There are several targets (IA-64, PowerPC, and others) which |
| don't represent pointers to functions as simply the address of |
| the function's entry point. For example, on the IA-64, a |
| function pointer points to a two-word descriptor, generated by |
| the linker, which contains the function's entry point, and the |
| value the IA-64 "global pointer" register should have --- to |
| support position-independent code. The linker generates |
| descriptors only for those functions whose addresses are taken. |
| |
| On such targets, it's difficult for GDB to convert an arbitrary |
| function address into a function pointer; it has to either find |
| an existing descriptor for that function, or call malloc and |
| build its own. On some targets, it is impossible for GDB to |
| build a descriptor at all: the descriptor must contain a jump |
| instruction; data memory cannot be executed; and code memory |
| cannot be modified. |
| |
| Upon entry to this function, if VAL is a value of type `function' |
| (that is, TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FUNC), then |
| value_address (val) is the address of the function. This is what |
| you'll get if you evaluate an expression like `main'. The call |
| to COERCE_ARRAY below actually does all the usual unary |
| conversions, which includes converting values of type `function' |
| to `pointer to function'. This is the challenging conversion |
| discussed above. Then, `unpack_long' will convert that pointer |
| back into an address. |
| |
| So, suppose the user types `disassemble foo' on an architecture |
| with a strange function pointer representation, on which GDB |
| cannot build its own descriptors, and suppose further that `foo' |
| has no linker-built descriptor. The address->pointer conversion |
| will signal an error and prevent the command from running, even |
| though the next step would have been to convert the pointer |
| directly back into the same address. |
| |
| The following shortcut avoids this whole mess. If VAL is a |
| function, just return its address directly. */ |
| if (TYPE_CODE (value_type (val)) == TYPE_CODE_FUNC |
| || TYPE_CODE (value_type (val)) == TYPE_CODE_METHOD) |
| return value_address (val); |
| |
| val = coerce_array (val); |
| |
| /* Some architectures (e.g. Harvard), map instruction and data |
| addresses onto a single large unified address space. For |
| instance: An architecture may consider a large integer in the |
| range 0x10000000 .. 0x1000ffff to already represent a data |
| addresses (hence not need a pointer to address conversion) while |
| a small integer would still need to be converted integer to |
| pointer to address. Just assume such architectures handle all |
| integer conversions in a single function. */ |
| |
| /* JimB writes: |
| |
| I think INTEGER_TO_ADDRESS is a good idea as proposed --- but we |
| must admonish GDB hackers to make sure its behavior matches the |
| compiler's, whenever possible. |
| |
| In general, I think GDB should evaluate expressions the same way |
| the compiler does. When the user copies an expression out of |
| their source code and hands it to a `print' command, they should |
| get the same value the compiler would have computed. Any |
| deviation from this rule can cause major confusion and annoyance, |
| and needs to be justified carefully. In other words, GDB doesn't |
| really have the freedom to do these conversions in clever and |
| useful ways. |
| |
| AndrewC pointed out that users aren't complaining about how GDB |
| casts integers to pointers; they are complaining that they can't |
| take an address from a disassembly listing and give it to `x/i'. |
| This is certainly important. |
| |
| Adding an architecture method like integer_to_address() certainly |
| makes it possible for GDB to "get it right" in all circumstances |
| --- the target has complete control over how things get done, so |
| people can Do The Right Thing for their target without breaking |
| anyone else. The standard doesn't specify how integers get |
| converted to pointers; usually, the ABI doesn't either, but |
| ABI-specific code is a more reasonable place to handle it. */ |
| |
| if (TYPE_CODE (value_type (val)) != TYPE_CODE_PTR |
| && !TYPE_IS_REFERENCE (value_type (val)) |
| && gdbarch_integer_to_address_p (gdbarch)) |
| return gdbarch_integer_to_address (gdbarch, value_type (val), |
| value_contents (val)); |
| |
| return unpack_long (value_type (val), value_contents (val)); |
| #endif |
| } |
| |
| /* Unpack raw data (copied from debugee, target byte order) at VALADDR |
| as a long, or as a double, assuming the raw data is described |
| by type TYPE. Knows how to convert different sizes of values |
| and can convert between fixed and floating point. We don't assume |
| any alignment for the raw data. Return value is in host byte order. |
| |
| If you want functions and arrays to be coerced to pointers, and |
| references to be dereferenced, call value_as_long() instead. |
| |
| C++: It is assumed that the front-end has taken care of |
| all matters concerning pointers to members. A pointer |
| to member which reaches here is considered to be equivalent |
| to an INT (or some size). After all, it is only an offset. */ |
| |
| LONGEST |
| unpack_long (struct type *type, const gdb_byte *valaddr) |
| { |
| enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); |
| enum type_code code = TYPE_CODE (type); |
| int len = TYPE_LENGTH (type); |
| int nosign = TYPE_UNSIGNED (type); |
| |
| switch (code) |
| { |
| case TYPE_CODE_TYPEDEF: |
| return unpack_long (check_typedef (type), valaddr); |
| case TYPE_CODE_ENUM: |
| case TYPE_CODE_FLAGS: |
| case TYPE_CODE_BOOL: |
| case TYPE_CODE_INT: |
| case TYPE_CODE_CHAR: |
| case TYPE_CODE_RANGE: |
| case TYPE_CODE_MEMBERPTR: |
| if (nosign) |
| return extract_unsigned_integer (valaddr, len, byte_order); |
| else |
| return extract_signed_integer (valaddr, len, byte_order); |
| |
| case TYPE_CODE_FLT: |
| case TYPE_CODE_DECFLOAT: |
| return target_float_to_longest (valaddr, type); |
| |
| case TYPE_CODE_PTR: |
| case TYPE_CODE_REF: |
| case TYPE_CODE_RVALUE_REF: |
| /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure |
| whether we want this to be true eventually. */ |
| return extract_typed_address (valaddr, type); |
| |
| default: |
| error (_("Value can't be converted to integer.")); |
| } |
| return 0; /* Placate lint. */ |
| } |
| |
| /* Unpack raw data (copied from debugee, target byte order) at VALADDR |
| as a CORE_ADDR, assuming the raw data is described by type TYPE. |
| We don't assume any alignment for the raw data. Return value is in |
| host byte order. |
| |
| If you want functions and arrays to be coerced to pointers, and |
| references to be dereferenced, call value_as_address() instead. |
| |
| C++: It is assumed that the front-end has taken care of |
| all matters concerning pointers to members. A pointer |
| to member which reaches here is considered to be equivalent |
| to an INT (or some size). After all, it is only an offset. */ |
| |
| CORE_ADDR |
| unpack_pointer (struct type *type, const gdb_byte *valaddr) |
| { |
| /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure |
| whether we want this to be true eventually. */ |
| return unpack_long (type, valaddr); |
| } |
| |
| bool |
| is_floating_value (struct value *val) |
| { |
| struct type *type = check_typedef (value_type (val)); |
| |
| if (is_floating_type (type)) |
| { |
| if (!target_float_is_valid (value_contents (val), type)) |
| error (_("Invalid floating value found in program.")); |
| return true; |
| } |
| |
| return false; |
| } |
| |
| |
| /* Get the value of the FIELDNO'th field (which must be static) of |
| TYPE. */ |
| |
| struct value * |
| value_static_field (struct type *type, int fieldno) |
| { |
| struct value *retval; |
| |
| switch (TYPE_FIELD_LOC_KIND (type, fieldno)) |
| { |
| case FIELD_LOC_KIND_PHYSADDR: |
| retval = value_at_lazy (TYPE_FIELD_TYPE (type, fieldno), |
| TYPE_FIELD_STATIC_PHYSADDR (type, fieldno)); |
| break; |
| case FIELD_LOC_KIND_PHYSNAME: |
| { |
| const char *phys_name = TYPE_FIELD_STATIC_PHYSNAME (type, fieldno); |
| /* TYPE_FIELD_NAME (type, fieldno); */ |
| struct block_symbol sym = lookup_symbol (phys_name, 0, VAR_DOMAIN, 0); |
| |
| if (sym.symbol == NULL) |
| { |
| /* With some compilers, e.g. HP aCC, static data members are |
| reported as non-debuggable symbols. */ |
| struct bound_minimal_symbol msym |
| = lookup_minimal_symbol (phys_name, NULL, NULL); |
| struct type *field_type = TYPE_FIELD_TYPE (type, fieldno); |
| |
| if (!msym.minsym) |
| retval = allocate_optimized_out_value (field_type); |
| else |
| retval = value_at_lazy (field_type, BMSYMBOL_VALUE_ADDRESS (msym)); |
| } |
| else |
| retval = value_of_variable (sym.symbol, sym.block); |
| break; |
| } |
| default: |
| gdb_assert_not_reached ("unexpected field location kind"); |
| } |
| |
| return retval; |
| } |
| |
| /* Change the enclosing type of a value object VAL to NEW_ENCL_TYPE. |
| You have to be careful here, since the size of the data area for the value |
| is set by the length of the enclosing type. So if NEW_ENCL_TYPE is bigger |
| than the old enclosing type, you have to allocate more space for the |
| data. */ |
| |
| void |
| set_value_enclosing_type (struct value *val, struct type *new_encl_type) |
| { |
| if (TYPE_LENGTH (new_encl_type) > TYPE_LENGTH (value_enclosing_type (val))) |
| { |
| check_type_length_before_alloc (new_encl_type); |
| val->contents |
| = (gdb_byte *) xrealloc (val->contents, TYPE_LENGTH (new_encl_type)); |
| } |
| |
| val->enclosing_type = new_encl_type; |
| } |
| |
| /* Given a value ARG1 (offset by OFFSET bytes) |
| of a struct or union type ARG_TYPE, |
| extract and return the value of one of its (non-static) fields. |
| FIELDNO says which field. */ |
| |
| struct value * |
| value_primitive_field (struct value *arg1, LONGEST offset, |
| int fieldno, struct type *arg_type) |
| { |
| struct value *v; |
| struct type *type; |
| struct gdbarch *arch = get_value_arch (arg1); |
| int unit_size = gdbarch_addressable_memory_unit_size (arch); |
| |
| arg_type = check_typedef (arg_type); |
| type = TYPE_FIELD_TYPE (arg_type, fieldno); |
| |
| /* 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 instead of zero. However, we do not |
| replace the typedef type by the target type, because we want |
| to keep the typedef in order to be able to print the type |
| description correctly. */ |
| check_typedef (type); |
| |
| if (TYPE_FIELD_BITSIZE (arg_type, fieldno)) |
| { |
| /* Handle packed fields. |
| |
| Create a new value for the bitfield, with bitpos and bitsize |
| set. If possible, arrange offset and bitpos so that we can |
| do a single aligned read of the size of the containing type. |
| Otherwise, adjust offset to the byte containing the first |
| bit. Assume that the address, offset, and embedded offset |
| are sufficiently aligned. */ |
| |
| LONGEST bitpos = TYPE_FIELD_BITPOS (arg_type, fieldno); |
| LONGEST container_bitsize = TYPE_LENGTH (type) * 8; |
| |
| v = allocate_value_lazy (type); |
| v->bitsize = TYPE_FIELD_BITSIZE (arg_type, fieldno); |
| if ((bitpos % container_bitsize) + v->bitsize <= container_bitsize |
| && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)) |
| v->bitpos = bitpos % container_bitsize; |
| else |
| v->bitpos = bitpos % 8; |
| v->offset = (value_embedded_offset (arg1) |
| + offset |
| + (bitpos - v->bitpos) / 8); |
| set_value_parent (v, arg1); |
| if (!value_lazy (arg1)) |
| value_fetch_lazy (v); |
| } |
| else if (fieldno < TYPE_N_BASECLASSES (arg_type)) |
| { |
| /* This field is actually a base subobject, so preserve the |
| entire object's contents for later references to virtual |
| bases, etc. */ |
| LONGEST boffset; |
| |
| /* Lazy register values with offsets are not supported. */ |
| if (VALUE_LVAL (arg1) == lval_register && value_lazy (arg1)) |
| value_fetch_lazy (arg1); |
| |
| /* We special case virtual inheritance here because this |
| requires access to the contents, which we would rather avoid |
| for references to ordinary fields of unavailable values. */ |
| if (BASETYPE_VIA_VIRTUAL (arg_type, fieldno)) |
| boffset = baseclass_offset (arg_type, fieldno, |
| value_contents (arg1), |
| value_embedded_offset (arg1), |
| value_address (arg1), |
| arg1); |
| else |
| boffset = TYPE_FIELD_BITPOS (arg_type, fieldno) / 8; |
| |
| if (value_lazy (arg1)) |
| v = allocate_value_lazy (value_enclosing_type (arg1)); |
| else |
| { |
| v = allocate_value (value_enclosing_type (arg1)); |
| value_contents_copy_raw (v, 0, arg1, 0, |
| TYPE_LENGTH (value_enclosing_type (arg1))); |
| } |
| v->type = type; |
| v->offset = value_offset (arg1); |
| v->embedded_offset = offset + value_embedded_offset (arg1) + boffset; |
| } |
| else if (NULL != TYPE_DATA_LOCATION (type)) |
| { |
| /* Field is a dynamic data member. */ |
| |
| gdb_assert (0 == offset); |
| /* We expect an already resolved data location. */ |
| gdb_assert (PROP_CONST == TYPE_DATA_LOCATION_KIND (type)); |
| /* For dynamic data types defer memory allocation |
| until we actual access the value. */ |
| v = allocate_value_lazy (type); |
| } |
| else |
| { |
| /* Plain old data member */ |
| offset += (TYPE_FIELD_BITPOS (arg_type, fieldno) |
| / (HOST_CHAR_BIT * unit_size)); |
| |
| /* Lazy register values with offsets are not supported. */ |
| if (VALUE_LVAL (arg1) == lval_register && value_lazy (arg1)) |
| value_fetch_lazy (arg1); |
| |
| if (value_lazy (arg1)) |
| v = allocate_value_lazy (type); |
| else |
| { |
| v = allocate_value (type); |
| value_contents_copy_raw (v, value_embedded_offset (v), |
| arg1, value_embedded_offset (arg1) + offset, |
| type_length_units (type)); |
| } |
| v->offset = (value_offset (arg1) + offset |
| + value_embedded_offset (arg1)); |
| } |
| set_value_component_location (v, arg1); |
| return v; |
| } |
| |
| /* Given a value ARG1 of a struct or union type, |
| extract and return the value of one of its (non-static) fields. |
| FIELDNO says which field. */ |
| |
| struct value * |
| value_field (struct value *arg1, int fieldno) |
| { |
| return value_primitive_field (arg1, 0, fieldno, value_type (arg1)); |
| } |
| |
| /* Return a non-virtual function as a value. |
| F is the list of member functions which contains the desired method. |
| J is an index into F which provides the desired method. |
| |
| We only use the symbol for its address, so be happy with either a |
| full symbol or a minimal symbol. */ |
| |
| struct value * |
| value_fn_field (struct value **arg1p, struct fn_field *f, |
| int j, struct type *type, |
| LONGEST offset) |
| { |
| struct value *v; |
| struct type *ftype = TYPE_FN_FIELD_TYPE (f, j); |
| const char *physname = TYPE_FN_FIELD_PHYSNAME (f, j); |
| struct symbol *sym; |
| struct bound_minimal_symbol msym; |
| |
| sym = lookup_symbol (physname, 0, VAR_DOMAIN, 0).symbol; |
| if (sym != NULL) |
| { |
| memset (&msym, 0, sizeof (msym)); |
| } |
| else |
| { |
| gdb_assert (sym == NULL); |
| msym = lookup_bound_minimal_symbol (physname); |
| if (msym.minsym == NULL) |
| return NULL; |
| } |
| |
| v = allocate_value (ftype); |
| VALUE_LVAL (v) = lval_memory; |
| if (sym) |
| { |
| set_value_address (v, BLOCK_START (SYMBOL_BLOCK_VALUE (sym))); |
| } |
| else |
| { |
| /* The minimal symbol might point to a function descriptor; |
| resolve it to the actual code address instead. */ |
| struct objfile *objfile = msym.objfile; |
| struct gdbarch *gdbarch = get_objfile_arch (objfile); |
| |
| set_value_address (v, |
| gdbarch_convert_from_func_ptr_addr |
| (gdbarch, BMSYMBOL_VALUE_ADDRESS (msym), ¤t_target)); |
| } |
| |
| if (arg1p) |
| { |
| if (type != value_type (*arg1p)) |
| *arg1p = value_ind (value_cast (lookup_pointer_type (type), |
| value_addr (*arg1p))); |
| |
| /* Move the `this' pointer according to the offset. |
| VALUE_OFFSET (*arg1p) += offset; */ |
| } |
| |
| return v; |
| } |
| |
| |
| |
| /* Unpack a bitfield of the specified FIELD_TYPE, from the object at |
| VALADDR, and store the result in *RESULT. |
| The bitfield starts at BITPOS bits and contains BITSIZE bits; if |
| BITSIZE is zero, then the length is taken from FIELD_TYPE. |
| |
| Extracting bits depends on endianness of the machine. Compute the |
| number of least significant bits to discard. For big endian machines, |
| we compute the total number of bits in the anonymous object, subtract |
| off the bit count from the MSB of the object to the MSB of the |
| bitfield, then the size of the bitfield, which leaves the LSB discard |
| count. For little endian machines, the discard count is simply the |
| number of bits from the LSB of the anonymous object to the LSB of the |
| bitfield. |
| |
| If the field is signed, we also do sign extension. */ |
| |
| static LONGEST |
| unpack_bits_as_long (struct type *field_type, const gdb_byte *valaddr, |
| LONGEST bitpos, LONGEST bitsize) |
| { |
| enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (field_type)); |
| ULONGEST val; |
| ULONGEST valmask; |
| int lsbcount; |
| LONGEST bytes_read; |
| LONGEST read_offset; |
| |
| /* Read the minimum number of bytes required; there may not be |
| enough bytes to read an entire ULONGEST. */ |
| field_type = check_typedef (field_type); |
| if (bitsize) |
| bytes_read = ((bitpos % 8) + bitsize + 7) / 8; |
| else |
| { |
| bytes_read = TYPE_LENGTH (field_type); |
| bitsize = 8 * bytes_read; |
| } |
| |
| read_offset = bitpos / 8; |
| |
| val = extract_unsigned_integer (valaddr + read_offset, |
| bytes_read, byte_order); |
| |
| /* Extract bits. See comment above. */ |
| |
| if (gdbarch_bits_big_endian (get_type_arch (field_type))) |
| lsbcount = (bytes_read * 8 - bitpos % 8 - bitsize); |
| else |
| lsbcount = (bitpos % 8); |
| val >>= lsbcount; |
| |
| /* If the field does not entirely fill a LONGEST, then zero the sign bits. |
| If the field is signed, and is negative, then sign extend. */ |
| |
| if (bitsize < 8 * (int) sizeof (val)) |
| { |
| valmask = (((ULONGEST) 1) << bitsize) - 1; |
| val &= valmask; |
| if (!TYPE_UNSIGNED (field_type)) |
| { |
| if (val & (valmask ^ (valmask >> 1))) |
| { |
| val |= ~valmask; |
| } |
| } |
| } |
| |
| return val; |
| } |
| |
| /* Unpack a field FIELDNO of the specified TYPE, from the object at |
| VALADDR + EMBEDDED_OFFSET. VALADDR points to the contents of |
| ORIGINAL_VALUE, which must not be NULL. See |
| unpack_value_bits_as_long for more details. */ |
| |
| int |
| unpack_value_field_as_long (struct type *type, const gdb_byte *valaddr, |
| LONGEST embedded_offset, int fieldno, |
| const struct value *val, LONGEST *result) |
| { |
| int bitpos = TYPE_FIELD_BITPOS (type, fieldno); |
| int bitsize = TYPE_FIELD_BITSIZE (type, fieldno); |
| struct type *field_type = TYPE_FIELD_TYPE (type, fieldno); |
| int bit_offset; |
| |
| gdb_assert (val != NULL); |
| |
| bit_offset = embedded_offset * TARGET_CHAR_BIT + bitpos; |
| if (value_bits_any_optimized_out (val, bit_offset, bitsize) |
| || !value_bits_available (val, bit_offset, bitsize)) |
| return 0; |
| |
| *result = unpack_bits_as_long (field_type, valaddr + embedded_offset, |
| bitpos, bitsize); |
| return 1; |
| } |
| |
| /* Unpack a field FIELDNO of the specified TYPE, from the anonymous |
| object at VALADDR. See unpack_bits_as_long for more details. */ |
| |
| LONGEST |
| unpack_field_as_long (struct type *type, const gdb_byte *valaddr, int fieldno) |
| { |
| int bitpos = TYPE_FIELD_BITPOS (type, fieldno); |
| int bitsize = TYPE_FIELD_BITSIZE (type, fieldno); |
| struct type *field_type = TYPE_FIELD_TYPE (type, fieldno); |
| |
| return unpack_bits_as_long (field_type, valaddr, bitpos, bitsize); |
| } |
| |
| /* Unpack a bitfield of BITSIZE bits found at BITPOS in the object at |
| VALADDR + EMBEDDEDOFFSET that has the type of DEST_VAL and store |
| the contents in DEST_VAL, zero or sign extending if the type of |
| DEST_VAL is wider than BITSIZE. VALADDR points to the contents of |
| VAL. If the VAL's contents required to extract the bitfield from |
| are unavailable/optimized out, DEST_VAL is correspondingly |
| marked unavailable/optimized out. */ |
| |
| void |
| unpack_value_bitfield (struct value *dest_val, |
| LONGEST bitpos, LONGEST bitsize, |
| const gdb_byte *valaddr, LONGEST embedded_offset, |
| const struct value *val) |
| { |
| enum bfd_endian byte_order; |
| int src_bit_offset; |
| int dst_bit_offset; |
| struct type *field_type = value_type (dest_val); |
| |
| byte_order = gdbarch_byte_order (get_type_arch (field_type)); |
| |
| /* First, unpack and sign extend the bitfield as if it was wholly |
| valid. Optimized out/unavailable bits are read as zero, but |
| that's OK, as they'll end up marked below. If the VAL is |
| wholly-invalid we may have skipped allocating its contents, |
| though. See allocate_optimized_out_value. */ |
| if (valaddr != NULL) |
| { |
| LONGEST num; |
| |
| num = unpack_bits_as_long (field_type, valaddr + embedded_offset, |
| bitpos, bitsize); |
| store_signed_integer (value_contents_raw (dest_val), |
| TYPE_LENGTH (field_type), byte_order, num); |
| } |
| |
| /* Now copy the optimized out / unavailability ranges to the right |
| bits. */ |
| src_bit_offset = embedded_offset * TARGET_CHAR_BIT + bitpos; |
| if (byte_order == BFD_ENDIAN_BIG) |
| dst_bit_offset = TYPE_LENGTH (field_type) * TARGET_CHAR_BIT - bitsize; |
| else |
| dst_bit_offset = 0; |
| value_ranges_copy_adjusted (dest_val, dst_bit_offset, |
| val, src_bit_offset, bitsize); |
| } |
| |
| /* Return a new value with type TYPE, which is FIELDNO field of the |
| object at VALADDR + EMBEDDEDOFFSET. VALADDR points to the contents |
| of VAL. If the VAL's contents required to extract the bitfield |
| from are unavailable/optimized out, the new value is |
| correspondingly marked unavailable/optimized out. */ |
| |
| struct value * |
| value_field_bitfield (struct type *type, int fieldno, |
| const gdb_byte *valaddr, |
| LONGEST embedded_offset, const struct value *val) |
| { |
| int bitpos = TYPE_FIELD_BITPOS (type, fieldno); |
| int bitsize = TYPE_FIELD_BITSIZE (type, fieldno); |
| struct value *res_val = allocate_value (TYPE_FIELD_TYPE (type, fieldno)); |
| |
| unpack_value_bitfield (res_val, bitpos, bitsize, |
| valaddr, embedded_offset, val); |
| |
| return res_val; |
| } |
| |
| /* Modify the value of a bitfield. ADDR points to a block of memory in |
| target byte order; the bitfield starts in the byte pointed to. FIELDVAL |
| is the desired value of the field, in host byte order. BITPOS and BITSIZE |
| indicate which bits (in target bit order) comprise the bitfield. |
| Requires 0 < BITSIZE <= lbits, 0 <= BITPOS % 8 + BITSIZE <= lbits, and |
| 0 <= BITPOS, where lbits is the size of a LONGEST in bits. */ |
| |
| void |
| modify_field (struct type *type, gdb_byte *addr, |
| LONGEST fieldval, LONGEST bitpos, LONGEST bitsize) |
| { |
| enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); |
| ULONGEST oword; |
| ULONGEST mask = (ULONGEST) -1 >> (8 * sizeof (ULONGEST) - bitsize); |
| LONGEST bytesize; |
| |
| /* Normalize BITPOS. */ |
| addr += bitpos / 8; |
| bitpos %= 8; |
| |
| /* If a negative fieldval fits in the field in question, chop |
| off the sign extension bits. */ |
| if ((~fieldval & ~(mask >> 1)) == 0) |
| fieldval &= mask; |
| |
| /* Warn if value is too big to fit in the field in question. */ |
| if (0 != (fieldval & ~mask)) |
| { |
| /* FIXME: would like to include fieldval in the message, but |
| we don't have a sprintf_longest. */ |
| warning (_("Value does not fit in %s bits."), plongest (bitsize)); |
| |
| /* Truncate it, otherwise adjoining fields may be corrupted. */ |
| fieldval &= mask; |
| } |
| |
| /* Ensure no bytes outside of the modified ones get accessed as it may cause |
| false valgrind reports. */ |
| |
| bytesize = (bitpos + bitsize + 7) / 8; |
| oword = extract_unsigned_integer (addr, bytesize, byte_order); |
| |
| /* Shifting for bit field depends on endianness of the target machine. */ |
| if (gdbarch_bits_big_endian (get_type_arch (type))) |
| bitpos = bytesize * 8 - bitpos - bitsize; |
| |
| oword &= ~(mask << bitpos); |
| oword |= fieldval << bitpos; |
| |
| store_unsigned_integer (addr, bytesize, byte_order, oword); |
| } |
| |
| /* Pack NUM into BUF using a target format of TYPE. */ |
| |
| void |
| pack_long (gdb_byte *buf, struct type *type, LONGEST num) |
| { |
| enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); |
| LONGEST len; |
| |
| type = check_typedef (type); |
| len = TYPE_LENGTH (type); |
| |
| switch (TYPE_CODE (type)) |
| { |
| case TYPE_CODE_INT: |
| case TYPE_CODE_CHAR: |
| case TYPE_CODE_ENUM: |
| case TYPE_CODE_FLAGS: |
| case TYPE_CODE_BOOL: |
| case TYPE_CODE_RANGE: |
| case TYPE_CODE_MEMBERPTR: |
| store_signed_integer (buf, len, byte_order, num); |
| break; |
| |
| case TYPE_CODE_REF: |
| case TYPE_CODE_RVALUE_REF: |
| case TYPE_CODE_PTR: |
| store_typed_address (buf, type, (CORE_ADDR) num); |
| break; |
| |
| case TYPE_CODE_FLT: |
| case TYPE_CODE_DECFLOAT: |
| target_float_from_longest (buf, type, num); |
| break; |
| |
| default: |
| error (_("Unexpected type (%d) encountered for integer constant."), |
| TYPE_CODE (type)); |
| } |
| } |
| |
| |
| /* Pack NUM into BUF using a target format of TYPE. */ |
| |
| static void |
| pack_unsigned_long (gdb_byte *buf, struct type *type, ULONGEST num) |
| { |
| LONGEST len; |
| enum bfd_endian byte_order; |
| |
| type = check_typedef (type); |
| len = TYPE_LENGTH (type); |
| byte_order = gdbarch_byte_order (get_type_arch (type)); |
| |
| switch (TYPE_CODE (type)) |
| { |
| case TYPE_CODE_INT: |
| case TYPE_CODE_CHAR: |
| case TYPE_CODE_ENUM: |
| case TYPE_CODE_FLAGS: |
| case TYPE_CODE_BOOL: |
| case TYPE_CODE_RANGE: |
| case TYPE_CODE_MEMBERPTR: |
| store_unsigned_integer (buf, len, byte_order, num); |
| break; |
| |
| case TYPE_CODE_REF: |
| case TYPE_CODE_RVALUE_REF: |
| case TYPE_CODE_PTR: |
| store_typed_address (buf, type, (CORE_ADDR) num); |
| break; |
| |
| case TYPE_CODE_FLT: |
| case TYPE_CODE_DECFLOAT: |
| target_float_from_ulongest (buf, type, num); |
| break; |
| |
| default: |
| error (_("Unexpected type (%d) encountered " |
| "for unsigned integer constant."), |
| TYPE_CODE (type)); |
| } |
| } |
| |
| |
| /* Convert C numbers into newly allocated values. */ |
| |
| struct value * |
| value_from_longest (struct type *type, LONGEST num) |
| { |
| struct value *val = allocate_value (type); |
| |
| pack_long (value_contents_raw (val), type, num); |
| return val; |
| } |
| |
| |
| /* Convert C unsigned numbers into newly allocated values. */ |
| |
| struct value * |
| value_from_ulongest (struct type *type, ULONGEST num) |
| { |
| struct value *val = allocate_value (type); |
| |
| pack_unsigned_long (value_contents_raw (val), type, num); |
| |
| return val; |
| } |
| |
| |
| /* Create a value representing a pointer of type TYPE to the address |
| ADDR. */ |
| |
| struct value * |
| value_from_pointer (struct type *type, CORE_ADDR addr) |
| { |
| struct value *val = allocate_value (type); |
| |
| store_typed_address (value_contents_raw (val), |
| check_typedef (type), addr); |
| return val; |
| } |
| |
| |
| /* Create a value of type TYPE whose contents come from VALADDR, if it |
| is non-null, and whose memory address (in the inferior) is |
| ADDRESS. The type of the created value may differ from the passed |
| type TYPE. Make sure to retrieve values new type after this call. |
| Note that TYPE is not passed through resolve_dynamic_type; this is |
| a special API intended for use only by Ada. */ |
| |
| struct value * |
| value_from_contents_and_address_unresolved (struct type *type, |
| const gdb_byte *valaddr, |
| CORE_ADDR address) |
| { |
| struct value *v; |
| |
| if (valaddr == NULL) |
| v = allocate_value_lazy (type); |
| else |
| v = value_from_contents (type, valaddr); |
| VALUE_LVAL (v) = lval_memory; |
| set_value_address (v, address); |
| return v; |
| } |
| |
| /* Create a value of type TYPE whose contents come from VALADDR, if it |
| is non-null, and whose memory address (in the inferior) is |
| ADDRESS. The type of the created value may differ from the passed |
| type TYPE. Make sure to retrieve values new type after this call. */ |
| |
| struct value * |
| value_from_contents_and_address (struct type *type, |
| const gdb_byte *valaddr, |
| CORE_ADDR address) |
| { |
| struct type *resolved_type = resolve_dynamic_type (type, valaddr, address); |
| struct type *resolved_type_no_typedef = check_typedef (resolved_type); |
| struct value *v; |
| |
| if (valaddr == NULL) |
| v = allocate_value_lazy (resolved_type); |
| else |
| v = value_from_contents (resolved_type, valaddr); |
| if (TYPE_DATA_LOCATION (resolved_type_no_typedef) != NULL |
| && TYPE_DATA_LOCATION_KIND (resolved_type_no_typedef) == PROP_CONST) |
| address = TYPE_DATA_LOCATION_ADDR (resolved_type_no_typedef); |
| VALUE_LVAL (v) = lval_memory; |
| set_value_address (v, address); |
| return v; |
| } |
| |
| /* Create a value of type TYPE holding the contents CONTENTS. |
| The new value is `not_lval'. */ |
| |
| struct value * |
| value_from_contents (struct type *type, const gdb_byte *contents) |
| { |
| struct value *result; |
| |
| result = allocate_value (type); |
| memcpy (value_contents_raw (result), contents, TYPE_LENGTH (type)); |
| return result; |
| } |
| |
| /* Extract a value from the history file. Input will be of the form |
| $digits or $$digits. See block comment above 'write_dollar_variable' |
| for details. */ |
| |
| struct value * |
| value_from_history_ref (const char *h, const char **endp) |
| { |
| int index, len; |
| |
| if (h[0] == '$') |
| len = 1; |
| else |
| return NULL; |
| |
| if (h[1] == '$') |
| len = 2; |
| |
| /* Find length of numeral string. */ |
| for (; isdigit (h[len]); len++) |
| ; |
| |
| /* Make sure numeral string is not part of an identifier. */ |
| if (h[len] == '_' || isalpha (h[len])) |
| return NULL; |
| |
| /* Now collect the index value. */ |
| if (h[1] == '$') |
| { |
| if (len == 2) |
| { |
| /* For some bizarre reason, "$$" is equivalent to "$$1", |
| rather than to "$$0" as it ought to be! */ |
| index = -1; |
| *endp += len; |
| } |
| else |
| { |
| char *local_end; |
| |
| index = -strtol (&h[2], &local_end, 10); |
| *endp = local_end; |
| } |
| } |
| else |
| { |
| if (len == 1) |
| { |
| /* "$" is equivalent to "$0". */ |
| index = 0; |
| *endp += len; |
| } |
| else |
| { |
| char *local_end; |
| |
| index = strtol (&h[1], &local_end, 10); |
| *endp = local_end; |
| } |
| } |
| |
| return access_value_history (index); |
| } |
| |
| /* Get the component value (offset by OFFSET bytes) of a struct or |
| union WHOLE. Component's type is TYPE. */ |
| |
| struct value * |
| value_from_component (struct value *whole, struct type *type, LONGEST offset) |
| { |
| struct value *v; |
| |
| if (VALUE_LVAL (whole) == lval_memory && value_lazy (whole)) |
| v = allocate_value_lazy (type); |
| else |
| { |
| v = allocate_value (type); |
| value_contents_copy (v, value_embedded_offset (v), |
| whole, value_embedded_offset (whole) + offset, |
| type_length_units (type)); |
| } |
| v->offset = value_offset (whole) + offset + value_embedded_offset (whole); |
| set_value_component_location (v, whole); |
| |
| return v; |
| } |
| |
| struct value * |
| coerce_ref_if_computed (const struct value *arg) |
| { |
| const struct lval_funcs *funcs; |
| |
| if (!TYPE_IS_REFERENCE (check_typedef (value_type (arg)))) |
| return NULL; |
| |
| if (value_lval_const (arg) != lval_computed) |
| return NULL; |
| |
| funcs = value_computed_funcs (arg); |
| if (funcs->coerce_ref == NULL) |
| return NULL; |
| |
| return funcs->coerce_ref (arg); |
| } |
| |
| /* Look at value.h for description. */ |
| |
| struct value * |
| readjust_indirect_value_type (struct value *value, struct type *enc_type, |
| const struct type *original_type, |
| const struct value *original_value) |
| { |
| /* Re-adjust type. */ |
| deprecated_set_value_type (value, TYPE_TARGET_TYPE (original_type)); |
| |
| /* Add embedding info. */ |
| set_value_enclosing_type (value, enc_type); |
| set_value_embedded_offset (value, value_pointed_to_offset (original_value)); |
| |
| /* We may be pointing to an object of some derived type. */ |
| return value_full_object (value, NULL, 0, 0, 0); |
| } |
| |
| struct value * |
| coerce_ref (struct value *arg) |
| { |
| struct type *value_type_arg_tmp = check_typedef (value_type (arg)); |
| struct value *retval; |
| struct type *enc_type; |
| |
| retval = coerce_ref_if_computed (arg); |
| if (retval) |
| return retval; |
| |
| if (!TYPE_IS_REFERENCE (value_type_arg_tmp)) |
| return arg; |
| |
| enc_type = check_typedef (value_enclosing_type (arg)); |
| enc_type = TYPE_TARGET_TYPE (enc_type); |
| |
| retval = value_at_lazy (enc_type, |
| unpack_pointer (value_type (arg), |
| value_contents (arg))); |
| enc_type = value_type (retval); |
| return readjust_indirect_value_type (retval, enc_type, |
| value_type_arg_tmp, arg); |
| } |
| |
| struct value * |
| coerce_array (struct value *arg) |
| { |
| struct type *type; |
| |
| arg = coerce_ref (arg); |
| type = check_typedef (value_type (arg)); |
| |
| switch (TYPE_CODE (type)) |
| { |
| case TYPE_CODE_ARRAY: |
| if (!TYPE_VECTOR (type) && current_language->c_style_arrays) |
| arg = value_coerce_array (arg); |
| break; |
| case TYPE_CODE_FUNC: |
| arg = value_coerce_function (arg); |
| break; |
| } |
| return arg; |
| } |
| |
| |
| /* Return the return value convention that will be used for the |
| specified type. */ |
| |
| enum return_value_convention |
| struct_return_convention (struct gdbarch *gdbarch, |
| struct value *function, struct type *value_type) |
| { |
| enum type_code code = TYPE_CODE (value_type); |
| |
| if (code == TYPE_CODE_ERROR) |
| error (_("Function return type unknown.")); |
| |
| /* Probe the architecture for the return-value convention. */ |
| return gdbarch_return_value (gdbarch, function, value_type, |
| NULL, NULL, NULL); |
| } |
| |
| /* Return true if the function returning the specified type is using |
| the convention of returning structures in memory (passing in the |
| address as a hidden first parameter). */ |
| |
| int |
| using_struct_return (struct gdbarch *gdbarch, |
| struct value *function, struct type *value_type) |
| { |
| if (TYPE_CODE (value_type) == TYPE_CODE_VOID) |
| /* A void return value is never in memory. See also corresponding |
| code in "print_return_value". */ |
| return 0; |
| |
| return (struct_return_convention (gdbarch, function, value_type) |
| != RETURN_VALUE_REGISTER_CONVENTION); |
| } |
| |
| /* Set the initialized field in a value struct. */ |
| |
| void |
| set_value_initialized (struct value *val, int status) |
| { |
| val->initialized = status; |
| } |
| |
| /* Return the initialized field in a value struct. */ |
| |
| int |
| value_initialized (const struct value *val) |
| { |
| return val->initialized; |
| } |
| |
| /* Load the actual content of a lazy value. Fetch the data from the |
| user's process and clear the lazy flag to indicate that the data in |
| the buffer is valid. |
| |
| If the value is zero-length, we avoid calling read_memory, which |
| would abort. We mark the value as fetched anyway -- all 0 bytes of |
| it. */ |
| |
| void |
| value_fetch_lazy (struct value *val) |
| { |
| gdb_assert (value_lazy (val)); |
| allocate_value_contents (val); |
| /* A value is either lazy, or fully fetched. The |
| availability/validity is only established as we try to fetch a |
| value. */ |
| gdb_assert (VEC_empty (range_s, val->optimized_out)); |
| gdb_assert (VEC_empty (range_s, val->unavailable)); |
| if (value_bitsize (val)) |
| { |
| /* To read a lazy bitfield, read the entire enclosing value. This |
| prevents reading the same block of (possibly volatile) memory once |
| per bitfield. It would be even better to read only the containing |
| word, but we have no way to record that just specific bits of a |
| value have been fetched. */ |
| struct type *type = check_typedef (value_type (val)); |
| struct value *parent = value_parent (val); |
| |
| if (value_lazy (parent)) |
| value_fetch_lazy (parent); |
| |
| unpack_value_bitfield (val, |
| value_bitpos (val), value_bitsize (val), |
| value_contents_for_printing (parent), |
| value_offset (val), parent); |
| } |
| else if (VALUE_LVAL (val) == lval_memory) |
| { |
| CORE_ADDR addr = value_address (val); |
| struct type *type = check_typedef (value_enclosing_type (val)); |
| |
| if (TYPE_LENGTH (type)) |
| read_value_memory (val, 0, value_stack (val), |
| addr, value_contents_all_raw (val), |
| type_length_units (type)); |
| } |
| else if (VALUE_LVAL (val) == lval_register) |
| { |
| struct frame_info *next_frame; |
| int regnum; |
| struct type *type = check_typedef (value_type (val)); |
| struct value *new_val = val, *mark = value_mark (); |
| |
| /* Offsets are not supported here; lazy register values must |
| refer to the entire register. */ |
| gdb_assert (value_offset (val) == 0); |
| |
| while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val)) |
| { |
| struct frame_id next_frame_id = VALUE_NEXT_FRAME_ID (new_val); |
| |
| next_frame = frame_find_by_id (next_frame_id); |
| regnum = VALUE_REGNUM (new_val); |
| |
| gdb_assert (next_frame != NULL); |
| |
| /* Convertible register routines are used for multi-register |
| values and for interpretation in different types |
| (e.g. float or int from a double register). Lazy |
| register values should have the register's natural type, |
| so they do not apply. */ |
| gdb_assert (!gdbarch_convert_register_p (get_frame_arch (next_frame), |
| regnum, type)); |
| |
| /* FRAME was obtained, above, via VALUE_NEXT_FRAME_ID. |
| Since a "->next" operation was performed when setting |
| this field, we do not need to perform a "next" operation |
| again when unwinding the register. That's why |
| frame_unwind_register_value() is called here instead of |
| get_frame_register_value(). */ |
| new_val = frame_unwind_register_value (next_frame, regnum); |
| |
| /* If we get another lazy lval_register value, it means the |
| register is found by reading it from NEXT_FRAME's next frame. |
| frame_unwind_register_value should never return a value with |
| the frame id pointing to NEXT_FRAME. If it does, it means we |
| either have two consecutive frames with the same frame id |
| in the frame chain, or some code is trying to unwind |
| behind get_prev_frame's back (e.g., a frame unwind |
| sniffer trying to unwind), bypassing its validations. In |
| any case, it should always be an internal error to end up |
| in this situation. */ |
| if (VALUE_LVAL (new_val) == lval_register |
| && value_lazy (new_val) |
| && frame_id_eq (VALUE_NEXT_FRAME_ID (new_val), next_frame_id)) |
| internal_error (__FILE__, __LINE__, |
| _("infinite loop while fetching a register")); |
| } |
| |
| /* If it's still lazy (for instance, a saved register on the |
| stack), fetch it. */ |
| if (value_lazy (new_val)) |
| value_fetch_lazy (new_val); |
| |
| /* Copy the contents and the unavailability/optimized-out |
| meta-data from NEW_VAL to VAL. */ |
| set_value_lazy (val, 0); |
| value_contents_copy (val, value_embedded_offset (val), |
| new_val, value_embedded_offset (new_val), |
| type_length_units (type)); |
| |
| if (frame_debug) |
| { |
| struct gdbarch *gdbarch; |
| struct frame_info *frame; |
| /* VALUE_FRAME_ID is used here, instead of VALUE_NEXT_FRAME_ID, |
| so that the frame level will be shown correctly. */ |
| frame = frame_find_by_id (VALUE_FRAME_ID (val)); |
| regnum = VALUE_REGNUM (val); |
| gdbarch = get_frame_arch (frame); |
| |
| fprintf_unfiltered (gdb_stdlog, |
| "{ value_fetch_lazy " |
| "(frame=%d,regnum=%d(%s),...) ", |
| frame_relative_level (frame), regnum, |
| user_reg_map_regnum_to_name (gdbarch, regnum)); |
| |
| fprintf_unfiltered (gdb_stdlog, "->"); |
| if (value_optimized_out (new_val)) |
| { |
| fprintf_unfiltered (gdb_stdlog, " "); |
| val_print_optimized_out (new_val, gdb_stdlog); |
| } |
| else |
| { |
| int i; |
| const gdb_byte *buf = value_contents (new_val); |
| |
| if (VALUE_LVAL (new_val) == lval_register) |
| fprintf_unfiltered (gdb_stdlog, " register=%d", |
| VALUE_REGNUM (new_val)); |
| else if (VALUE_LVAL (new_val) == lval_memory) |
| fprintf_unfiltered (gdb_stdlog, " address=%s", |
| paddress (gdbarch, |
| value_address (new_val))); |
| else |
| fprintf_unfiltered (gdb_stdlog, " computed"); |
| |
| fprintf_unfiltered (gdb_stdlog, " bytes="); |
| fprintf_unfiltered (gdb_stdlog, "["); |
| for (i = 0; i < register_size (gdbarch, regnum); i++) |
| fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]); |
| fprintf_unfiltered (gdb_stdlog, "]"); |
| } |
| |
| fprintf_unfiltered (gdb_stdlog, " }\n"); |
| } |
| |
| /* Dispose of the intermediate values. This prevents |
| watchpoints from trying to watch the saved frame pointer. */ |
| value_free_to_mark (mark); |
| } |
| else if (VALUE_LVAL (val) == lval_computed |
| && value_computed_funcs (val)->read != NULL) |
| value_computed_funcs (val)->read (val); |
| else |
| internal_error (__FILE__, __LINE__, _("Unexpected lazy value type.")); |
| |
| set_value_lazy (val, 0); |
| } |
| |
| /* Implementation of the convenience function $_isvoid. */ |
| |
| static struct value * |
| isvoid_internal_fn (struct gdbarch *gdbarch, |
| const struct language_defn *language, |
| void *cookie, int argc, struct value **argv) |
| { |
| int ret; |
| |
| if (argc != 1) |
| error (_("You must provide one argument for $_isvoid.")); |
| |
| ret = TYPE_CODE (value_type (argv[0])) == TYPE_CODE_VOID; |
| |
| return value_from_longest (builtin_type (gdbarch)->builtin_int, ret); |
| } |
| |
| void |
| _initialize_values (void) |
| { |
| add_cmd ("convenience", no_class, show_convenience, _("\ |
| Debugger convenience (\"$foo\") variables and functions.\n\ |
| Convenience variables are created when you assign them values;\n\ |
| thus, \"set $foo=1\" gives \"$foo\" the value 1. Values may be any type.\n\ |
| \n\ |
| A few convenience variables are given values automatically:\n\ |
| \"$_\"holds the last address examined with \"x\" or \"info lines\",\n\ |
| \"$__\" holds the contents of the last address examined with \"x\"." |
| #ifdef HAVE_PYTHON |
| "\n\n\ |
| Convenience functions are defined via the Python API." |
| #endif |
| ), &showlist); |
| add_alias_cmd ("conv", "convenience", no_class, 1, &showlist); |
| |
| add_cmd ("values", no_set_class, show_values, _("\ |
| Elements of value history around item number IDX (or last ten)."), |
| &showlist); |
| |
| add_com ("init-if-undefined", class_vars, init_if_undefined_command, _("\ |
| Initialize a convenience variable if necessary.\n\ |
| init-if-undefined VARIABLE = EXPRESSION\n\ |
| Set an internal VARIABLE to the result of the EXPRESSION if it does not\n\ |
| exist or does not contain a value. The EXPRESSION is not evaluated if the\n\ |
| VARIABLE is already initialized.")); |
| |
| add_prefix_cmd ("function", no_class, function_command, _("\ |
| Placeholder command for showing help on convenience functions."), |
| &functionlist, "function ", 0, &cmdlist); |
| |
| add_internal_function ("_isvoid", _("\ |
| Check whether an expression is void.\n\ |
| Usage: $_isvoid (expression)\n\ |
| Return 1 if the expression is void, zero otherwise."), |
| isvoid_internal_fn, NULL); |
| |
| add_setshow_zuinteger_unlimited_cmd ("max-value-size", |
| class_support, &max_value_size, _("\ |
| Set maximum sized value gdb will load from the inferior."), _("\ |
| Show maximum sized value gdb will load from the inferior."), _("\ |
| Use this to control the maximum size, in bytes, of a value that gdb\n\ |
| will load from the inferior. Setting this value to 'unlimited'\n\ |
| disables checking.\n\ |
| Setting this does not invalidate already allocated values, it only\n\ |
| prevents future values, larger than this size, from being allocated."), |
| set_max_value_size, |
| show_max_value_size, |
| &setlist, &showlist); |
| } |