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Update intree gdb/kgdb to handle 2 dwarf types:

Browse Source 
DW_OP_GNU_uninit
DW_OP_piece

This squashes the warnings about type 0x93 not known in kgdb when opening a kernel crash dump.

Upstream refs:
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commit;h=87808bd699575a850139a1f916512ab7a47fd496
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commit;h=42be36b328ae784ae6981da7c7cab95b67ed7737
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commit;h=23572ecadc89af384c1804ad7692f32c55fbfc80

Differential Revision:	https://reviews.freebsd.org/D2534
Reviewed by:	emaste, jhb, davide
This commit is contained in:
sbruno 2015-05-17 15:49:38 +00:00
parent a416f5f996
commit d177e52109
8 changed files with 172 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
contrib/gcc/dwarf2.h
View File

@ -547,6 +547,7 @@ enum dwarf_location_atom
DW_OP_bit_piece = 0x9d,
/* GNU extensions. */
DW_OP_GNU_push_tls_address = 0xe0,
DW_OP_GNU_uninit = 0xf0,
/* HP extensions. */
DW_OP_HP_unknown = 0xe0, /* Ouch, the same as GNU_push_tls_address. */
DW_OP_HP_is_value = 0xe1,

4
contrib/gdb/gdb/c-valprint.c
View File

@ -559,6 +559,10 @@ c_value_print (struct value *val, struct ui_file *stream, int format,
fprintf_filtered (stream, ") ");
}
}
if (!value_initialized (val))
fprintf_filtered (stream, " [uninitialized] ");
if (objectprint && (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_CLASS))
{
/* Attempt to determine real type of object */

60
contrib/gdb/gdb/dwarf2expr.c
View File

@ -42,6 +42,8 @@ new_dwarf_expr_context (void)
retval->stack_len = 0;
retval->stack_allocated = 10;
retval->stack = xmalloc (retval->stack_allocated * sizeof (CORE_ADDR));
retval->num_pieces = 0;
retval->pieces = 0;
return retval;
}
@ -51,6 +53,7 @@ void
free_dwarf_expr_context (struct dwarf_expr_context *ctx)
{
xfree (ctx->stack);
xfree (ctx->pieces);
xfree (ctx);
}
@ -100,6 +103,29 @@ dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n)
}
/* Add a new piece to CTX's piece list. */
static void
add_piece (struct dwarf_expr_context *ctx,
int in_reg, CORE_ADDR value, ULONGEST size)
{
struct dwarf_expr_piece *p;
ctx->num_pieces++;
if (ctx->pieces)
ctx->pieces = xrealloc (ctx->pieces,
(ctx->num_pieces
* sizeof (struct dwarf_expr_piece)));
else
ctx->pieces = xmalloc (ctx->num_pieces
* sizeof (struct dwarf_expr_piece));
p = &ctx->pieces[ctx->num_pieces - 1];
p->in_reg = in_reg;
p->value = value;
p->size = size;
}
/* Evaluate the expression at ADDR (LEN bytes long) using the context
CTX. */
@ -230,6 +256,7 @@ execute_stack_op (struct dwarf_expr_context *ctx, unsigned char *op_ptr,
unsigned char *op_end)
{
ctx->in_reg = 0;
ctx->initialized = 1; /* Default is initialized. */
while (op_ptr < op_end)
{
@ -356,9 +383,12 @@ execute_stack_op (struct dwarf_expr_context *ctx, unsigned char *op_ptr,
case DW_OP_reg29:
case DW_OP_reg30:
case DW_OP_reg31:
if (op_ptr != op_end && *op_ptr != DW_OP_piece)
error ("DWARF-2 expression error: DW_OP_reg operations must be "
"used either alone or in conjuction with DW_OP_piece.");
if (op_ptr != op_end
&& *op_ptr != DW_OP_piece
&& *op_ptr != DW_OP_bit_piece
&& *op_ptr != DW_OP_GNU_uninit)
error (_("DWARF-2 expression error: DW_OP_reg operations must be "
"used either alone or in conjuction with DW_OP_piece."));
result = op - DW_OP_reg0;
ctx->in_reg = 1;
@ -661,6 +691,30 @@ execute_stack_op (struct dwarf_expr_context *ctx, unsigned char *op_ptr,
case DW_OP_nop:
goto no_push;
case DW_OP_piece:
{
ULONGEST size;
CORE_ADDR addr_or_regnum;
/* Record the piece. */
op_ptr = read_uleb128 (op_ptr, op_end, &size);
addr_or_regnum = dwarf_expr_fetch (ctx, 0);
add_piece (ctx, ctx->in_reg, addr_or_regnum, size);
/* Pop off the address/regnum, and clear the in_reg flag. */
dwarf_expr_pop (ctx);
ctx->in_reg = 0;
}
goto no_push;
case DW_OP_GNU_uninit:
if (op_ptr != op_end)
error (_("DWARF-2 expression error: DW_OP_GNU_unint must always "
"be the very last op."));
ctx->initialized = 0;
goto no_push;
default:
error ("Unhandled dwarf expression opcode 0x%x", op);
}

45
contrib/gdb/gdb/dwarf2expr.h
View File

@ -74,6 +74,51 @@ struct dwarf_expr_context
/* Non-zero if the result is in a register. The register number
will be on the expression stack. */
int in_reg;
/* Initialization status of variable: Non-zero if variable has been
initialized; zero otherwise. */
int initialized;
/* An array of pieces. PIECES points to its first element;
NUM_PIECES is its length.
Each time DW_OP_piece is executed, we add a new element to the
end of this array, recording the current top of the stack, the
current in_reg flag, and the size given as the operand to
DW_OP_piece. We then pop the top value from the stack, clear the
in_reg flag, and resume evaluation.
The Dwarf spec doesn't say whether DW_OP_piece pops the top value
from the stack. We do, ensuring that clients of this interface
expecting to see a value left on the top of the stack (say, code
evaluating frame base expressions or CFA's specified with
DW_CFA_def_cfa_expression) will get an error if the expression
actually marks all the values it computes as pieces.
If an expression never uses DW_OP_piece, num_pieces will be zero.
(It would be nice to present these cases as expressions yielding
a single piece, with in_reg clear, so that callers need not
distinguish between the no-DW_OP_piece and one-DW_OP_piece cases.
But expressions with no DW_OP_piece operations have no value to
place in a piece's 'size' field; the size comes from the
surrounding data. So the two cases need to be handled
separately.) */
int num_pieces;
struct dwarf_expr_piece *pieces;
};
/* A piece of an object, as recorded by DW_OP_piece or DW_OP_bit_piece. */
struct dwarf_expr_piece
{
/* If IN_REG is zero, then the piece is in memory, and VALUE is its address.
If IN_REG is non-zero, then the piece is in a register, and VALUE
is the register number. */
int in_reg;
/* This piece's address or register number. */
CORE_ADDR value;
/* The length of the piece, in bytes. */
ULONGEST size;
};
struct dwarf_expr_context *new_dwarf_expr_context (void);

41
contrib/gdb/gdb/dwarf2loc.c
View File

@ -206,6 +206,7 @@ dwarf2_evaluate_loc_desc (struct symbol *var, struct frame_info *frame,
struct objfile *objfile)
{
CORE_ADDR result;
struct gdbarch *arch = get_frame_arch (frame);
struct value *retval;
struct dwarf_expr_baton baton;
struct dwarf_expr_context *ctx;
@ -230,7 +231,32 @@ dwarf2_evaluate_loc_desc (struct symbol *var, struct frame_info *frame,
dwarf_expr_eval (ctx, data, size);
result = dwarf_expr_fetch (ctx, 0);
if (ctx->in_reg)
if (ctx->num_pieces > 0)
{
int i;
long offset = 0;
bfd_byte *contents;
retval = allocate_value (SYMBOL_TYPE (var));
contents = VALUE_CONTENTS_RAW (retval);
for (i = 0; i < ctx->num_pieces; i++)
{
struct dwarf_expr_piece *p = &ctx->pieces[i];
if (p->in_reg)
{
bfd_byte regval[MAX_REGISTER_SIZE];
int gdb_regnum = DWARF2_REG_TO_REGNUM (p->value);
get_frame_register (frame, gdb_regnum, regval);
memcpy (contents + offset, regval, p->size);
}
else /* In memory? */
{
read_memory (p->value, contents + offset, p->size);
}
offset += p->size;
}
}
else if (ctx->in_reg)
{
int regnum = DWARF2_REG_TO_REGNUM (result);
retval = value_from_register (SYMBOL_TYPE (var), regnum, frame);
@ -245,6 +271,8 @@ dwarf2_evaluate_loc_desc (struct symbol *var, struct frame_info *frame,
VALUE_ADDRESS (retval) = result;
}
set_value_initialized (retval, ctx->initialized);
free_dwarf_expr_context (ctx);
return retval;
@ -322,6 +350,17 @@ dwarf2_loc_desc_needs_frame (unsigned char *data, unsigned short size)
in_reg = ctx->in_reg;
if (ctx->num_pieces > 0)
{
int i;
/* If the location has several pieces, and any of them are in
registers, then we will need a frame to fetch them from. */
for (i = 0; i < ctx->num_pieces; i++)
if (ctx->pieces[i].in_reg)
in_reg = 1;
}
free_dwarf_expr_context (ctx);
return baton.needs_frame || in_reg;

5
contrib/gdb/gdb/dwarf2read.c
View File

@ -7110,6 +7110,8 @@ dwarf_stack_op_name (unsigned op)
/* GNU extensions. */
case DW_OP_GNU_push_tls_address:
return "DW_OP_GNU_push_tls_address";
case DW_OP_GNU_uninit:
return "DW_OP_GNU_uninit";
default:
return "OP_<unknown>";
}
@ -7634,6 +7636,9 @@ decode_locdesc (struct dwarf_block *blk, struct dwarf2_cu *cu)
dwarf2_complex_location_expr_complaint ();
break;
case DW_OP_GNU_uninit:
break;
default:
complaint (&symfile_complaints, "unsupported stack op: '%s'",
dwarf_stack_op_name (op));

3
contrib/gdb/gdb/value.h
View File

@ -165,6 +165,9 @@ struct value
/* The BFD section associated with this value. */
asection *bfd_section;
/* If value is a variable, is it initialized or not. */
int initialized;
/* Actual contents of the value. For use of this value; setting
it uses the stuff above. Not valid if lazy is nonzero.
Target byte-order. We force it to be aligned properly for any

17
contrib/gdb/gdb/values.c
View File

@ -101,6 +101,7 @@ allocate_value (struct type *type)
VALUE_EMBEDDED_OFFSET (val) = 0;
VALUE_POINTED_TO_OFFSET (val) = 0;
val->modifiable = 1;
val->initialized = 1; /* Default to initialized. */
return val;
}
@ -1311,6 +1312,22 @@ using_struct_return (struct type *value_type, int gcc_p)
== RETURN_VALUE_STRUCT_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 (struct value *val)
{
return val->initialized;
}
void
_initialize_values (void)
{