sizes), and this is simpler.) */
\f
-/* Generating bytecode from GDB expressions: the `trace' kludge */
-
-/* The compiler in this file is a general-purpose mechanism for
- translating GDB expressions into bytecode. One ought to be able to
- find a million and one uses for it.
-
- However, at the moment it is HOPELESSLY BRAIN-DAMAGED for the sake
- of expediency. Let he who is without sin cast the first stone.
-
- For the data tracing facility, we need to insert `trace' bytecodes
- before each data fetch; this records all the memory that the
- expression touches in the course of evaluation, so that memory will
- be available when the user later tries to evaluate the expression
- in GDB.
-
- This should be done (I think) in a post-processing pass, that walks
- an arbitrary agent expression and inserts `trace' operations at the
- appropriate points. But it's much faster to just hack them
- directly into the code. And since we're in a crunch, that's what
- I've done.
-
- Setting the flag trace_kludge to non-zero enables the code that
- emits the trace bytecodes at the appropriate points. */
-int trace_kludge;
-
-/* Inspired by trace_kludge, this indicates that pointers to chars
- should get an added tracenz bytecode to record nonzero bytes, up to
- a length that is the value of trace_string_kludge. */
-int trace_string_kludge;
-
/* Scan for all static fields in the given class, including any base
classes, and generate tracing bytecodes for each. */
struct agent_expr *ax, struct axs_value *value)
{
int string_trace = 0;
- if (trace_string_kludge
+ if (ax->trace_string
&& TYPE_CODE (value->type) == TYPE_CODE_PTR
&& c_textual_element_type (check_typedef (TYPE_TARGET_TYPE (value->type)),
's'))
string_trace = 1;
- if (trace_kludge)
+ if (ax->tracing)
switch (value->kind)
{
case axs_rvalue:
if (string_trace)
{
- ax_const_l (ax, trace_string_kludge);
+ ax_const_l (ax, ax->trace_string);
ax_simple (ax, aop_tracenz);
}
else
if (string_trace)
{
ax_simple (ax, aop_ref32);
- ax_const_l (ax, trace_string_kludge);
+ ax_const_l (ax, ax->trace_string);
ax_simple (ax, aop_tracenz);
}
}
if (string_trace)
{
ax_reg (ax, value->u.reg);
- ax_const_l (ax, trace_string_kludge);
+ ax_const_l (ax, ax->trace_string);
ax_simple (ax, aop_tracenz);
}
break;
ax_simple (ax, aop_pop);
/* To trace C++ classes with static fields stored elsewhere. */
- if (trace_kludge
+ if (ax->tracing
&& (TYPE_CODE (value->type) == TYPE_CODE_STRUCT
|| TYPE_CODE (value->type) == TYPE_CODE_UNION))
gen_trace_static_fields (gdbarch, ax, value->type);
static void
gen_fetch (struct agent_expr *ax, struct type *type)
{
- if (trace_kludge)
+ if (ax->tracing)
{
/* Record the area of memory we're about to fetch. */
ax_trace_quick (ax, TYPE_LENGTH (type));
/* Add the offset. */
gen_offset (ax, offset / TARGET_CHAR_BIT);
- if (trace_kludge)
+ if (ax->tracing)
{
/* Record the area of memory we're about to fetch. */
ax_trace_quick (ax, op_size / TARGET_CHAR_BIT);
if (tsv)
{
ax_tsv (ax, aop_setv, tsv->number);
- if (trace_kludge)
+ if (ax->tracing)
ax_tsv (ax, aop_tracev, tsv->number);
}
else
{
/* The tsv will be the left half of the binary operation. */
ax_tsv (ax, aop_getv, tsv->number);
- if (trace_kludge)
+ if (ax->tracing)
ax_tsv (ax, aop_tracev, tsv->number);
/* Trace state variables are always 64-bit integers. */
value1.kind = axs_rvalue;
gen_expr_binop_rest (exp, op2, pc, ax, value, &value1, &value2);
/* We have a result of the binary op, set the tsv. */
ax_tsv (ax, aop_setv, tsv->number);
- if (trace_kludge)
+ if (ax->tracing)
ax_tsv (ax, aop_tracev, tsv->number);
}
else
if (tsv)
{
ax_tsv (ax, aop_getv, tsv->number);
- if (trace_kludge)
+ if (ax->tracing)
ax_tsv (ax, aop_tracev, tsv->number);
/* Trace state variables are always 64-bit integers. */
value->kind = axs_rvalue;
struct agent_expr *
gen_trace_for_var (CORE_ADDR scope, struct gdbarch *gdbarch,
- struct symbol *var)
+ struct symbol *var, int trace_string)
{
struct cleanup *old_chain = 0;
struct agent_expr *ax = new_agent_expr (gdbarch, scope);
old_chain = make_cleanup_free_agent_expr (ax);
- trace_kludge = 1;
+ ax->tracing = 1;
+ ax->trace_string = trace_string;
gen_var_ref (gdbarch, ax, &value, var);
/* If there is no actual variable to trace, flag it by returning
caller can then use the ax_reqs function to discover which
registers it relies upon. */
struct agent_expr *
-gen_trace_for_expr (CORE_ADDR scope, struct expression *expr)
+gen_trace_for_expr (CORE_ADDR scope, struct expression *expr,
+ int trace_string)
{
struct cleanup *old_chain = 0;
struct agent_expr *ax = new_agent_expr (expr->gdbarch, scope);
old_chain = make_cleanup_free_agent_expr (ax);
pc = expr->elts;
- trace_kludge = 1;
+ ax->tracing = 1;
+ ax->trace_string = trace_string;
value.optimized_out = 0;
gen_expr (expr, &pc, ax, &value);
old_chain = make_cleanup_free_agent_expr (ax);
pc = expr->elts;
- trace_kludge = 0;
+ ax->tracing = 0;
value.optimized_out = 0;
gen_expr (expr, &pc, ax, &value);
}
struct agent_expr *
-gen_trace_for_return_address (CORE_ADDR scope, struct gdbarch *gdbarch)
+gen_trace_for_return_address (CORE_ADDR scope, struct gdbarch *gdbarch,
+ int trace_string)
{
struct cleanup *old_chain = 0;
struct agent_expr *ax = new_agent_expr (gdbarch, scope);
old_chain = make_cleanup_free_agent_expr (ax);
- trace_kludge = 1;
+ ax->tracing = 1;
+ ax->trace_string = trace_string;
gdbarch_gen_return_address (gdbarch, ax, &value, scope);
old_chain = make_cleanup_free_agent_expr (ax);
+ /* We're computing values, not doing side effects. */
+ ax->tracing = 0;
+
/* Evaluate and push the args on the stack in reverse order,
for simplicity of collecting them on the target side. */
for (tem = nargs - 1; tem >= 0; --tem)
{
pc = exprs[tem]->elts;
- /* We're computing values, not doing side effects. */
- trace_kludge = 0;
value.optimized_out = 0;
gen_expr (exprs[tem], &pc, ax, &value);
require_rvalue (ax, &value);
struct expression *expr;
struct agent_expr *agent;
const char *arg;
+ int trace_string = 0;
if (!eval)
{
- trace_string_kludge = 0;
if (*exp == '/')
- exp = decode_agent_options (exp);
+ exp = decode_agent_options (exp, &trace_string);
}
arg = exp;
if (!eval && strcmp (arg, "$_ret") == 0)
{
- agent = gen_trace_for_return_address (pc, get_current_arch ());
+ agent = gen_trace_for_return_address (pc, get_current_arch (),
+ trace_string);
old_chain = make_cleanup_free_agent_expr (agent);
}
else
expr = parse_exp_1 (&arg, pc, block_for_pc (pc), 0);
old_chain = make_cleanup (free_current_contents, &expr);
if (eval)
- agent = gen_eval_for_expr (pc, expr);
+ {
+ gdb_assert (trace_string == 0);
+ agent = gen_eval_for_expr (pc, expr);
+ }
else
- agent = gen_trace_for_expr (pc, expr);
+ agent = gen_trace_for_expr (pc, expr, trace_string);
make_cleanup_free_agent_expr (agent);
}
/* Parse any collection options, such as /s for strings. */
const char *
-decode_agent_options (const char *exp)
+decode_agent_options (const char *exp, int *trace_string)
{
struct value_print_options opts;
+ *trace_string = 0;
+
if (*exp != '/')
return exp;
/* Allow an optional decimal number giving an explicit maximum
string length, defaulting it to the "print elements" value;
so "collect/s80 mystr" gets at most 80 bytes of string. */
- trace_string_kludge = opts.print_max;
+ *trace_string = opts.print_max;
exp++;
if (*exp >= '0' && *exp <= '9')
- trace_string_kludge = atoi (exp);
+ *trace_string = atoi (exp);
while (*exp >= '0' && *exp <= '9')
exp++;
}
if (cmd_cfunc_eq (c, collect_pseudocommand))
{
- trace_string_kludge = 0;
+ int trace_string = 0;
+
if (*p == '/')
- p = decode_agent_options (p);
+ p = decode_agent_options (p, &trace_string);
do
{ /* Repeat over a comma-separated list. */
/* We have something to collect, make sure that the expr to
bytecode translator can handle it and that it's not too
long. */
- aexpr = gen_trace_for_expr (loc->address, exp);
+ aexpr = gen_trace_for_expr (loc->address, exp, trace_string);
make_cleanup_free_agent_expr (aexpr);
if (aexpr->len > MAX_AGENT_EXPR_LEN)
struct symbol *sym,
struct gdbarch *gdbarch,
long frame_regno, long frame_offset,
- CORE_ADDR scope)
+ CORE_ADDR scope,
+ int trace_string)
{
unsigned long len;
unsigned int reg;
struct agent_expr *aexpr;
struct cleanup *old_chain1 = NULL;
- aexpr = gen_trace_for_var (scope, gdbarch, sym);
+ aexpr = gen_trace_for_var (scope, gdbarch, sym, trace_string);
/* It can happen that the symbol is recorded as a computed
location, but it's been optimized away and doesn't actually
long frame_regno;
long frame_offset;
int count;
+ int trace_string;
};
/* The callback for the locals and args iterators. */
struct add_local_symbols_data *p = cb_data;
collect_symbol (p->collect, sym, p->gdbarch, p->frame_regno,
- p->frame_offset, p->pc);
+ p->frame_offset, p->pc, p->trace_string);
p->count++;
}
static void
add_local_symbols (struct collection_list *collect,
struct gdbarch *gdbarch, CORE_ADDR pc,
- long frame_regno, long frame_offset, int type)
+ long frame_regno, long frame_offset, int type,
+ int trace_string)
{
struct block *block;
struct add_local_symbols_data cb_data;
cb_data.frame_regno = frame_regno;
cb_data.frame_offset = frame_offset;
cb_data.count = 0;
+ cb_data.trace_string = trace_string;
if (type == 'L')
{
if (cmd_cfunc_eq (cmd, collect_pseudocommand))
{
- trace_string_kludge = 0;
+ int trace_string = 0;
+
if (*action_exp == '/')
- action_exp = decode_agent_options (action_exp);
+ action_exp = decode_agent_options (action_exp, &trace_string);
do
{ /* Repeat over a comma-separated list. */
tloc->address,
frame_reg,
frame_offset,
- 'A');
+ 'A',
+ trace_string);
action_exp = strchr (action_exp, ','); /* more? */
}
else if (0 == strncasecmp ("$loc", action_exp, 4))
tloc->address,
frame_reg,
frame_offset,
- 'L');
+ 'L',
+ trace_string);
action_exp = strchr (action_exp, ','); /* more? */
}
else if (0 == strncasecmp ("$_ret", action_exp, 5))
struct cleanup *old_chain1 = NULL;
aexpr = gen_trace_for_return_address (tloc->address,
- tloc->gdbarch);
+ tloc->gdbarch,
+ trace_string);
old_chain1 = make_cleanup_free_agent_expr (aexpr);
tloc->gdbarch,
frame_reg,
frame_offset,
- tloc->address);
+ tloc->address,
+ trace_string);
break;
default: /* Full-fledged expression. */
- aexpr = gen_trace_for_expr (tloc->address, exp);
+ aexpr = gen_trace_for_expr (tloc->address, exp,
+ trace_string);
old_chain1 = make_cleanup_free_agent_expr (aexpr);
char *cmd = NULL;
struct cleanup *old_chain
= make_cleanup (free_current_contents, &cmd);
+ int trace_string = 0;
if (*action_exp == '/')
- action_exp = decode_agent_options (action_exp);
+ action_exp = decode_agent_options (action_exp, &trace_string);
do
{ /* Repeat over a comma-separated list. */