28 Apr
2009
28 Apr
'09
8:54 p.m.
Module: sip-router
Branch: andrei/type_conversion
Commit: 3c8fc182ae386713f15e6a0362924e72b257c31e
URL:
http://git.sip-router.org/cgi-bin/gitweb.cgi/sip-router/?a=commit;h=3c8fc18…
Author: Andrei Pelinescu-Onciul <andrei(a)iptel.org>
Committer: Andrei Pelinescu-Onciul <andrei(a)iptel.org>
Date: Tue Apr 28 18:34:03 2009 +0200
core expr eval: fix assoc., commut and 0 adding for +, ==
- fix associativity for the generic plus: because of the non-fixed
argument types (can work with strings integers or both in the
same type), RVE_PLUS_OP is associative _only_ if the operand
types match.
Non-assoc. example: "a" + 1 + "2" (can be "a12" or
"a3").
Instead of adding extra checks for the same type, rely on the
optimizer having already replaced RVE_PLUS_OP with RVE_IPLUS_OP
or RVE_CONCAT_OP => RVE_PLUS_OP will be used only when the
operands types are mixed or cannot be determined (e.g. AVP), or
when script optimizations are turned off (-O0).
- fix commutativity for the generic plus. Similar to the above.
Non-commut. example: 1 + "2" == 3, but "2" + 1 == "21".
- fix commutativity for the generic == and !=.
Non. commut. example: 0 == "" , but "" != 0.
Similar fix as above, relying on the optimizer and the type specific
operators: RVE_IEQ_OP, RVE_IDIFF_OP, RVE_STREQ_OP and
RVE_STRDIFF_OP.
- fix $v + 0 / 0 + $v -> $v optimizations. Because of the generic
plus and recent changes that allow int + str, even if the result
is an int (left side operant is integer), 0 + $v can be
different from $v. E.g.: 0+"1" == 1, which is different from
"1".
---
rvalue.c | 37 +++++++++++++++++++++++++++----------
1 files changed, 27 insertions(+), 10 deletions(-)
diff --git a/rvalue.c b/rvalue.c
index 7e82503..9a74cda 100644
--- a/rvalue.c
+++ b/rvalue.c
@@ -2281,6 +2281,9 @@ static int rve_op_is_assoc(enum rval_expr_op op)
case RVE_MINUS_OP:
return 0;
case RVE_PLUS_OP:
+ /* the generic plus is not assoc, e.g.
+ "a" + 1 + "2" => "a12" in one case and
"a3" in the other */
+ return 0;
case RVE_IPLUS_OP:
case RVE_CONCAT_OP:
case RVE_MUL_OP:
@@ -2308,7 +2311,7 @@ static int rve_op_is_assoc(enum rval_expr_op op)
/** returns true if the operator is commutative. */
-static int rve_op_is_commutative(enum rval_expr_op op, enum rval_type type)
+static int rve_op_is_commutative(enum rval_expr_op op)
{
switch(op){
case RVE_NONE_OP:
@@ -2325,7 +2328,10 @@ static int rve_op_is_commutative(enum rval_expr_op op, enum
rval_type type)
case RVE_MINUS_OP:
return 0;
case RVE_PLUS_OP:
- return type==RV_INT; /* commutative only for INT*/
+ /* non commut. when diff. type
+ (e.g 1 + "2" != "2" + 1 ) => non commut. in general
+ (specific same type versions are covered by IPLUS & CONCAT) */
+ return 0;
case RVE_IPLUS_OP:
case RVE_MUL_OP:
case RVE_BAND_OP:
@@ -2345,11 +2351,11 @@ static int rve_op_is_commutative(enum rval_expr_op op, enum
rval_type type)
return 0;
case RVE_DIFF_OP:
case RVE_EQ_OP:
-#if !defined(UNDEF_EQ_ALWAYS_FALSE) && !defined(UNDEF_EQ_UNDEF_TRUE)
- return 1;
-#else
+ /* non. commut. in general, only for same type e.g.:
+ "" == 0 diff. 0 == "" ( "" == "0" and 0 ==
0)
+ same type versions are covered by IEQ, IDIFF, STREQ, STRDIFF
+ */
return 0 /* asymmetrical undef handling */;
-#endif
}
return 0;
}
@@ -2658,8 +2664,19 @@ static int rve_opt_01(struct rval_expr* rve, enum rval_type
rve_type)
case RVE_PLUS_OP:
case RVE_IPLUS_OP:
/* we must make sure that this is an int PLUS
- (because "foo"+0 is valid => "foo0") */
- if ((i==0) && ((op==RVE_IPLUS_OP)||(rve_type==RV_INT))){
+ (because "foo"+0 is valid => "foo0")
+ Even if overall type is RV_INT, it's still not safe
+ to optimize a generic PLUS: 0 + $v is not always equivalent
+ to $v (e.g. 0+"1" ==1 != "1") => optimize only if
+ IPLUS (always safe since it converts to int first) or
+ if generic PLUS and result is integer (rve_type) and
+ expression is of the form $v+ct (and not ct+$v).
+ TODO: dropping PLUS_OP all together and relying on the
+ optimizer replacing safe PLUS_OP with IPLUS_OP or CONCAT_OP
+ will simplify things.
+ */
+ if ((i==0) && ((op==RVE_IPLUS_OP)||
+ (rve_type==RV_INT && ct_rve==rve->right.rve))){
/* $v + 0 -> $v
* 0 + $v -> $v */
rve_destroy(ct_rve);
@@ -2908,7 +2925,7 @@ static int rve_optimize(struct rval_expr* rve)
trv->v.s.len, trv->v.s.s, rve->op);
ret=1;
}else if (rve_is_constant(rve->left.rve->left.rve) &&
- rve_op_is_commutative(rve->op, type)){
+ rve_op_is_commutative(rve->op)){
/* op(op(a, $v), b) => op(op(a, b), $v) */
/* rv= op(a, b) */
tmp_rve.op=rve->op;
@@ -2950,7 +2967,7 @@ static int rve_optimize(struct rval_expr* rve)
if ((rve->op==rve->right.rve->op) && rve_op_is_assoc(rve->op)){
/* op(a, op(...)) */
if (rve_is_constant(rve->right.rve->right.rve) &&
- rve_op_is_commutative(rve->op, type)){
+ rve_op_is_commutative(rve->op)){
/* op(a, op($v, b)) => op(op(a, b), $v) */
/* rv= op(a, b) */
tmp_rve.op=rve->op;