handle_AND_condition and handle_AND_op gave false outputs. This could be
seen in the test case in validation/sm_bits1.c the expected output was
0x1 for possible and 0x0 for definitely set. However, in the previous
state 0x0 was output for both possibly set and definitely set.
Signed-off-by: Harshvardhan Jha <harshvardhan.jha@xxxxxxxxxx>
---
smatch_extra.c | 72 +++++++++----------------------------------
smatch_extra.h | 1 +
validation/sm_bits1.c | 23 ++++++++++++++
3 files changed, 39 insertions(+), 57 deletions(-)
create mode 100644 validation/sm_bits1.c
diff --git a/smatch_extra.c b/smatch_extra.c
index b29235fc..e864646a 100644
--- a/smatch_extra.c
+++ b/smatch_extra.c
@@ -2059,24 +2059,6 @@ static void match_comparison(struct expression *expr)
handle_comparison(type, left, expr->op, right);
}
-static sval_t get_high_mask(sval_t known)
-{
- sval_t ret;
- int i;
-
- ret = known;
- ret.value = 0;
-
- for (i = type_bits(known.type) - 1; i >= 0; i--) {
- if (known.uvalue & (1ULL << i))
- ret.uvalue |= (1ULL << i);
- else
- return ret;
-
- }
- return ret;
-}
-
static bool handle_bit_test(struct expression *expr)
{
struct range_list *orig_rl, *rl;
@@ -2122,59 +2104,35 @@ static bool handle_bit_test(struct expression *expr)
return true;
}
-static void handle_AND_op(struct expression *var, sval_t known)
+static void handle_AND_op(struct symbol *type, struct expression *var, sval_t known)
{
- struct range_list *orig_rl;
- struct range_list *true_rl = NULL;
- struct range_list *false_rl = NULL;
- int bit;
- sval_t low_mask = known;
- sval_t high_mask;
- sval_t max;
-
- get_absolute_rl(var, &orig_rl);
+ sval_t sval = { .type = type };
+ struct expression *bits_expr;
- if (known.value > 0) {
- bit = ffsll(known.value) - 1;
- low_mask.uvalue = (1ULL << bit) - 1;
- true_rl = remove_range(orig_rl, sval_type_val(known.type, 0), low_mask);
- }
- high_mask = get_high_mask(known);
- if (high_mask.value) {
- bit = ffsll(high_mask.value) - 1;
- low_mask.uvalue = (1ULL << bit) - 1;
-
- false_rl = orig_rl;
- if (sval_is_negative(rl_min(orig_rl)))
- false_rl = remove_range(false_rl, sval_type_min(known.type), sval_type_val(known.type, -1));
- false_rl = remove_range(false_rl, low_mask, sval_type_max(known.type));
- if (type_signed(high_mask.type) && type_unsigned(rl_type(false_rl))) {
- false_rl = remove_range(false_rl,
- sval_type_val(rl_type(false_rl), sval_type_max(known.type).uvalue),
- sval_type_val(rl_type(false_rl), -1));
- }
- } else if (known.value == 1 &&
- get_hard_max(var, &max) &&
- sval_cmp(max, rl_max(orig_rl)) == 0 &&
- max.value & 1) {
- false_rl = remove_range(orig_rl, max, max);
+ if (known.uvalue == 0) {
+ set_true_false_states_expr(my_id, var, alloc_estate_empty(), NULL);
+ return;
}
- set_extra_expr_true_false(var,
- true_rl ? alloc_estate_rl(true_rl) : NULL,
- false_rl ? alloc_estate_rl(false_rl) : NULL);
+
+ sval.uvalue = 1ULL << (ffsll(known.uvalue) - 1);
+ bits_expr = value_expr_sval(sval);
+ handle_comparison(type, var, SPECIAL_GTE, bits_expr);
}
static void handle_AND_condition(struct expression *expr)
{
sval_t known;
+ struct symbol *type;
if (handle_bit_test(expr))
return;
+ type = get_type(expr);
+
if (get_implied_value(expr->left, &known))
- handle_AND_op(expr->right, known);
+ handle_AND_op(type, expr->right, known);
else if (get_implied_value(expr->right, &known))
- handle_AND_op(expr->left, known);
+ handle_AND_op(type, expr->left, known);
}
static void handle_MOD_condition(struct expression *expr)
diff --git a/smatch_extra.h b/smatch_extra.h
index 3d75c7c9..e07b06bb 100644
--- a/smatch_extra.h
+++ b/smatch_extra.h
@@ -215,6 +215,7 @@ void function_comparison(struct expression *left, int comparison, struct express
/* smatch_expressions.c */
struct expression *zero_expr();
struct expression *value_expr(long long val);
+struct expression *value_expr_sval(sval_t sval);
struct expression *member_expression(struct expression *deref, int op, struct ident *member);
struct expression *preop_expression(struct expression *expr, int op);
struct expression *deref_expression(struct expression *expr);
diff --git a/validation/sm_bits1.c b/validation/sm_bits1.c
new file mode 100644
index 00000000..a2b75c00
--- /dev/null
+++ b/validation/sm_bits1.c
@@ -0,0 +1,23 @@
+#include "../check_debug.h"
+
+unsigned int frob();
+
+void test(void)
+{
+ unsigned int x = frob();
+ if (x & ~1)
+ return;
+ __smatch_bits(x);
+ __smatch_implied(x);
+}
+
+
+/*
+ * check-name: smatch bits 1
+ * check-command: smatch sm_bits1.c
+ *
+ * check-output-start
+sm_bits1.c:10 test() bit info 'x': definitely set 0x0. possibly set 0x1.
+sm_bits1.c:11 test() implied: x = '0-1'
+ * check-output-end
+ */
--
2.32.0
