[PATCH 04/13] evaluate_subexp_standard: Eliminate one goto

Pedro Alves
2017-07-13T02:19:47Z

A following patch will want to factor out a bit of
evaluate_subexp_standard, and it'd be handy to reuse the code under the
"nosideret:" label there too. This commits moves it to a separate
function as preparation for that.

gdb/ChangeLog:
yyyy-mm-dd Pedro Alves <palves@redhat.com>

* eval.c (eval_skip_value): New function.
(evaluate_subexp_standard): Use it.
---
gdb/eval.c | 110 ++++++++++++++++++++++++++++++-------------------------------
1 file changed, 55 insertions(+), 55 deletions(-)

diff --git a/gdb/eval.c b/gdb/eval.c
index 0e77f0a..639e06e 100644
--- a/gdb/eval.c
+++ b/gdb/eval.c
@@ -695,6 +695,14 @@ evaluate_var_msym_value (enum noside noside,
}
}

+/* Helper for returning a value when handling EVAL_SKIP. */
+
+static value *
+eval_skip_value (expression *exp)
+{
+ return value_from_longest (builtin_type (exp->gdbarch)->builtin_int, 1);
+}
+
struct value *
evaluate_subexp_standard (struct type *expect_type,
struct expression *exp, int *pos,
@@ -727,7 +735,7 @@ evaluate_subexp_standard (struct type *expect_type,
tem = longest_to_int (exp->elts[pc + 2].longconst);
(*pos) += 4 + BYTES_TO_EXP_ELEM (tem + 1);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
arg1 = value_aggregate_elt (exp->elts[pc + 1].type,
&exp->elts[pc + 3].string,
expect_type, 0, noside);
@@ -754,7 +762,7 @@ evaluate_subexp_standard (struct type *expect_type,
case OP_VAR_VALUE:
(*pos) += 3;
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);

/* JYG: We used to just return value_zero of the symbol type
if we're asked to avoid side effects. Otherwise we return
@@ -795,7 +803,7 @@ evaluate_subexp_standard (struct type *expect_type,
case OP_VAR_ENTRY_VALUE:
(*pos) += 2;
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);

{
struct symbol *sym = exp->elts[pc + 1].symbol;
@@ -860,7 +868,7 @@ evaluate_subexp_standard (struct type *expect_type,
tem = longest_to_int (exp->elts[pc + 1].longconst);
(*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
type = language_string_char_type (exp->language_defn, exp->gdbarch);
return value_string (&exp->elts[pc + 2].string, tem, type);

@@ -869,9 +877,7 @@ evaluate_subexp_standard (struct type *expect_type,
tem = longest_to_int (exp->elts[pc + 1].longconst);
(*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
if (noside == EVAL_SKIP)
- {
- goto nosideret;
- }
+ return eval_skip_value (exp);
return value_nsstring (exp->gdbarch, &exp->elts[pc + 2].string, tem + 1);

case OP_ARRAY:
@@ -1011,7 +1017,7 @@ evaluate_subexp_standard (struct type *expect_type,
argvec[tem] = evaluate_subexp_with_coercion (exp, pos, noside);
}
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
return value_array (tem2, tem3, argvec);

case TERNOP_SLICE:
@@ -1023,7 +1029,7 @@ evaluate_subexp_standard (struct type *expect_type,
= value_as_long (evaluate_subexp (NULL_TYPE, exp, pos, noside));

if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
return value_slice (array, lowbound, upper - lowbound + 1);
}

@@ -1050,7 +1056,7 @@ evaluate_subexp_standard (struct type *expect_type,

(*pos) += 3 + BYTES_TO_EXP_ELEM (len + 1);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);

if (sel[len] != 0)
sel[len] = 0; /* Make sure it's terminated. */
@@ -1292,7 +1298,7 @@ evaluate_subexp_standard (struct type *expect_type,
}

if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);

if (noside == EVAL_AVOID_SIDE_EFFECTS)
{
@@ -1586,7 +1592,7 @@ evaluate_subexp_standard (struct type *expect_type,
argvec[tem] = 0;

if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);

if (op == OP_ADL_FUNC)
{
@@ -1860,7 +1866,7 @@ evaluate_subexp_standard (struct type *expect_type,
argvec[tem] = evaluate_subexp_with_coercion (exp, pos, noside);
argvec[tem] = 0; /* signal end of arglist */
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
goto do_call_it;

default:
@@ -1881,7 +1887,7 @@ evaluate_subexp_standard (struct type *expect_type,
(*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
arg3 = value_struct_elt (&arg1, NULL, &exp->elts[pc + 2].string,
NULL, "structure");
if (noside == EVAL_AVOID_SIDE_EFFECTS)
@@ -1893,7 +1899,7 @@ evaluate_subexp_standard (struct type *expect_type,
(*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);

/* Check to see if operator '->' has been overloaded. If so replace
arg1 with the value returned by evaluating operator->(). */
@@ -1954,7 +1960,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside);

if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);

type = check_typedef (value_type (arg2));
switch (TYPE_CODE (type))
@@ -2003,7 +2009,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
arg2 = evaluate_subexp_with_coercion (exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (binop_user_defined_p (op, arg1, arg2))
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
else
@@ -2057,7 +2063,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
arg2 = evaluate_subexp_with_coercion (exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (binop_user_defined_p (op, arg1, arg2))
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
else if (ptrmath_type_p (exp->language_defn, value_type (arg1))
@@ -2076,7 +2082,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
arg2 = evaluate_subexp_with_coercion (exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (binop_user_defined_p (op, arg1, arg2))
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
else if (ptrmath_type_p (exp->language_defn, value_type (arg1))
@@ -2109,7 +2115,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (binop_user_defined_p (op, arg1, arg2))
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
else
@@ -2152,7 +2158,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (binop_user_defined_p (op, arg1, arg2))
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
else
@@ -2189,13 +2195,8 @@ evaluate_subexp_standard (struct type *expect_type,
if (noside == EVAL_SKIP)
{
if (nargs > 0)
- {
- continue;
- }
- else
- {
- goto nosideret;
- }
+ continue;
+ return eval_skip_value (exp);
}
/* FIXME: EVAL_AVOID_SIDE_EFFECTS handling may not be correct. */
if (noside == EVAL_AVOID_SIDE_EFFECTS)
@@ -2294,7 +2295,7 @@ evaluate_subexp_standard (struct type *expect_type,
if (noside == EVAL_SKIP)
{
evaluate_subexp (NULL_TYPE, exp, pos, noside);
- goto nosideret;
+ return eval_skip_value (exp);
}

oldpos = *pos;
@@ -2321,7 +2322,7 @@ evaluate_subexp_standard (struct type *expect_type,
if (noside == EVAL_SKIP)
{
evaluate_subexp (NULL_TYPE, exp, pos, noside);
- goto nosideret;
+ return eval_skip_value (exp);
}

oldpos = *pos;
@@ -2347,7 +2348,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
arg2 = evaluate_subexp (value_type (arg1), exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (binop_user_defined_p (op, arg1, arg2))
{
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
@@ -2364,7 +2365,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
arg2 = evaluate_subexp (value_type (arg1), exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (binop_user_defined_p (op, arg1, arg2))
{
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
@@ -2381,7 +2382,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
arg2 = evaluate_subexp (value_type (arg1), exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (binop_user_defined_p (op, arg1, arg2))
{
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
@@ -2398,7 +2399,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
arg2 = evaluate_subexp (value_type (arg1), exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (binop_user_defined_p (op, arg1, arg2))
{
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
@@ -2415,7 +2416,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
arg2 = evaluate_subexp (value_type (arg1), exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (binop_user_defined_p (op, arg1, arg2))
{
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
@@ -2432,7 +2433,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
arg2 = evaluate_subexp (value_type (arg1), exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (binop_user_defined_p (op, arg1, arg2))
{
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
@@ -2449,7 +2450,7 @@ evaluate_subexp_standard (struct type *expect_type,
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
type = check_typedef (value_type (arg2));
if (TYPE_CODE (type) != TYPE_CODE_INT
&& TYPE_CODE (type) != TYPE_CODE_ENUM)
@@ -2469,7 +2470,7 @@ evaluate_subexp_standard (struct type *expect_type,
case UNOP_PLUS:
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (unop_user_defined_p (op, arg1))
return value_x_unop (arg1, op, noside);
else
@@ -2481,7 +2482,7 @@ evaluate_subexp_standard (struct type *expect_type,
case UNOP_NEG:
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (unop_user_defined_p (op, arg1))
return value_x_unop (arg1, op, noside);
else
@@ -2496,7 +2497,7 @@ evaluate_subexp_standard (struct type *expect_type,

arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (unop_user_defined_p (UNOP_COMPLEMENT, arg1))
return value_x_unop (arg1, UNOP_COMPLEMENT, noside);
else
@@ -2508,7 +2509,7 @@ evaluate_subexp_standard (struct type *expect_type,
case UNOP_LOGICAL_NOT:
arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (unop_user_defined_p (op, arg1))
return value_x_unop (arg1, op, noside);
else
@@ -2527,7 +2528,7 @@ evaluate_subexp_standard (struct type *expect_type,
error (_("Attempt to dereference pointer "
"to member without an object"));
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (unop_user_defined_p (op, arg1))
return value_x_unop (arg1, op, noside);
else if (noside == EVAL_AVOID_SIDE_EFFECTS)
@@ -2565,7 +2566,7 @@ evaluate_subexp_standard (struct type *expect_type,
if (noside == EVAL_SKIP)
{
evaluate_subexp (NULL_TYPE, exp, pos, EVAL_SKIP);
- goto nosideret;
+ return eval_skip_value (exp);
}
else
{
@@ -2579,7 +2580,7 @@ evaluate_subexp_standard (struct type *expect_type,
if (noside == EVAL_SKIP)
{
evaluate_subexp (NULL_TYPE, exp, pos, EVAL_SKIP);
- goto nosideret;
+ return eval_skip_value (exp);
}
return evaluate_subexp_for_sizeof (exp, pos, noside);

@@ -2588,7 +2589,7 @@ evaluate_subexp_standard (struct type *expect_type,
type = exp->elts[pc + 1].type;
arg1 = evaluate_subexp (type, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (type != value_type (arg1))
arg1 = value_cast (type, arg1);
return arg1;
@@ -2598,7 +2599,7 @@ evaluate_subexp_standard (struct type *expect_type,
type = value_type (arg1);
arg1 = evaluate_subexp (type, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (type != value_type (arg1))
arg1 = value_cast (type, arg1);
return arg1;
@@ -2608,7 +2609,7 @@ evaluate_subexp_standard (struct type *expect_type,
type = value_type (arg1);
arg1 = evaluate_subexp (type, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
return value_dynamic_cast (type, arg1);

case UNOP_REINTERPRET_CAST:
@@ -2616,14 +2617,14 @@ evaluate_subexp_standard (struct type *expect_type,
type = value_type (arg1);
arg1 = evaluate_subexp (type, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
return value_reinterpret_cast (type, arg1);

case UNOP_MEMVAL:
(*pos) += 2;
arg1 = evaluate_subexp (expect_type, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (noside == EVAL_AVOID_SIDE_EFFECTS)
return value_zero (exp->elts[pc + 1].type, lval_memory);
else
@@ -2635,7 +2636,7 @@ evaluate_subexp_standard (struct type *expect_type,
type = value_type (arg1);
arg1 = evaluate_subexp (expect_type, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (noside == EVAL_AVOID_SIDE_EFFECTS)
return value_zero (type, lval_memory);
else
@@ -2645,7 +2646,7 @@ evaluate_subexp_standard (struct type *expect_type,
(*pos) += 3;
arg1 = evaluate_subexp (expect_type, exp, pos, noside);
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
if (noside == EVAL_AVOID_SIDE_EFFECTS)
return value_zero (exp->elts[pc + 2].type, lval_memory);
else
@@ -2768,7 +2769,7 @@ evaluate_subexp_standard (struct type *expect_type,
easier to accommodate expressions that contain types. */
(*pos) += 2;
if (noside == EVAL_SKIP)
- goto nosideret;
+ return eval_skip_value (exp);
else if (noside == EVAL_AVOID_SIDE_EFFECTS)
return allocate_value (exp->elts[pc + 1].type);
else
@@ -2779,7 +2780,7 @@ evaluate_subexp_standard (struct type *expect_type,
if (noside == EVAL_SKIP)
{
evaluate_subexp (NULL_TYPE, exp, pos, EVAL_SKIP);
- goto nosideret;
+ return eval_skip_value (exp);
}
else if (noside == EVAL_AVOID_SIDE_EFFECTS)
{
@@ -2844,8 +2845,7 @@ evaluate_subexp_standard (struct type *expect_type,
"evaluate that kind of expression"));
}

-nosideret:
- return value_from_longest (builtin_type (exp->gdbarch)->builtin_int, 1);
+ gdb_assert_not_reached ("missed return?");
}
\f
/* Evaluate a subexpression of EXP, at index *POS,
--
2.5.5