Currently, every expression in Kconfig files produces a new abstract
syntax tree (AST), even if it is identical to a previously encountered
one.
Consider the following code:
config FOO
bool "FOO"
depends on (A || B) && C
config BAR
bool "BAR"
depends on (A || B) && C
config BAZ
bool "BAZ"
depends on A || B
The "depends on" lines are similar, but currently a separate AST is
allocated for each one.
The current data structure looks like this:
FOO->dep ==> AND BAR->dep ==> AND BAZ->dep ==> OR
/ \ / \ / \
OR C OR C A B
/ \ / \
A B A B
This is redundant; FOO->dep and BAR->dep have identical ASTs but
different memory instances.
We can optimize this; FOO->dep and BAR->dep can share the same AST, and
BAZ->dep can reference its sub tree.
The optimized data structure looks like this:
FOO->dep, BAR->dep ==> AND
/ \
BAZ->dep ==> OR C
/ \
A B
This commit introduces a hash table to keep track of allocated
expressions. If an identical expression is found, it is reused.
This does not necessarily result in memory savings, as menu_finalize()
transforms expressions without freeing up stale ones.
One further optimization that can be easily implemented is caching the
expression's value. Once FOO's dependency, (A || B) && C, is calculated,
it can be cached, eliminating the need to recalculate it for BAR.
This commit also reverts commit e983b7b17ad1 ("kconfig/menu.c: fix
multiple references to expressions in menu_add_prop()").
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
---
scripts/include/hash.h | 13 ++
scripts/kconfig/expr.c | 381 +++++++++++++------------------------
scripts/kconfig/expr.h | 16 +-
scripts/kconfig/internal.h | 4 +
scripts/kconfig/menu.c | 33 +---
5 files changed, 170 insertions(+), 277 deletions(-)
diff --git a/scripts/include/hash.h b/scripts/include/hash.h
index ce2bc43b308b..efa904368a62 100644
--- a/scripts/include/hash.h
+++ b/scripts/include/hash.h
@@ -12,4 +12,17 @@ static inline unsigned int hash_str(const char *s)
return hash;
}
+/* simplified version of functions from include/linux/hash.h */
+#define GOLDEN_RATIO_32 0x61C88647
+
+static inline unsigned int hash_32(unsigned int val)
+{
+ return 0x61C88647 * val;
+}
+
+static inline unsigned int hash_ptr(const void *ptr)
+{
+ return hash_32((unsigned int)(unsigned long)ptr);
+}
+
#endif /* HASH_H */
diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c
index 5b826d197f12..b7cfaf1a22e6 100644
--- a/scripts/kconfig/expr.c
+++ b/scripts/kconfig/expr.c
@@ -9,45 +9,68 @@
#include <stdlib.h>
#include <string.h>
+#include <hash.h>
#include <xalloc.h>
+#include "internal.h"
#include "lkc.h"
#define DEBUG_EXPR 0
+HASHTABLE_DEFINE(expr_hashtable, EXPR_HASHSIZE);
+
static struct expr *expr_eliminate_yn(struct expr *e);
+/**
+ * expr_lookup - return the expression for the given type and sub-nodes
+ * This looks up an expression with the specified type and sub-nodes. If such
+ * an expression is found in the hash table, it is returned. Otherwise, a new
+ * expression node is allocated and added to the hash table.
+ * @type: expression type
+ * @l: left node
+ * @r: right node
+ * return: expression
+ */
+static struct expr *expr_lookup(enum expr_type type, void *l, void *r)
+{
+ struct expr *e;
+ int hash;
+
+ hash = hash_32((unsigned int)type ^ hash_ptr(l) ^ hash_ptr(r));
+
+ hash_for_each_possible(expr_hashtable, e, node, hash) {
+ if (e->type == type && e->left._initdata == l &&
+ e->right._initdata == r)
+ return e;
+ }
+
+ e = xmalloc(sizeof(*e));
+ e->type = type;
+ e->left._initdata = l;
+ e->right._initdata = r;
+
+ hash_add(expr_hashtable, &e->node, hash);
+
+ return e;
+}
+
struct expr *expr_alloc_symbol(struct symbol *sym)
{
- struct expr *e = xcalloc(1, sizeof(*e));
- e->type = E_SYMBOL;
- e->left.sym = sym;
- return e;
+ return expr_lookup(E_SYMBOL, sym, NULL);
}
struct expr *expr_alloc_one(enum expr_type type, struct expr *ce)
{
- struct expr *e = xcalloc(1, sizeof(*e));
- e->type = type;
- e->left.expr = ce;
- return e;
+ return expr_lookup(type, ce, NULL);
}
struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e2)
{
- struct expr *e = xcalloc(1, sizeof(*e));
- e->type = type;
- e->left.expr = e1;
- e->right.expr = e2;
- return e;
+ return expr_lookup(type, e1, e2);
}
struct expr *expr_alloc_comp(enum expr_type type, struct symbol *s1, struct symbol *s2)
{
- struct expr *e = xcalloc(1, sizeof(*e));
- e->type = type;
- e->left.sym = s1;
- e->right.sym = s2;
- return e;
+ return expr_lookup(type, s1, s2);
}
struct expr *expr_alloc_and(struct expr *e1, struct expr *e2)
@@ -64,76 +87,6 @@ struct expr *expr_alloc_or(struct expr *e1, struct expr *e2)
return e2 ? expr_alloc_two(E_OR, e1, e2) : e1;
}
-struct expr *expr_copy(const struct expr *org)
-{
- struct expr *e;
-
- if (!org)
- return NULL;
-
- e = xmalloc(sizeof(*org));
- memcpy(e, org, sizeof(*org));
- switch (org->type) {
- case E_SYMBOL:
- e->left = org->left;
- break;
- case E_NOT:
- e->left.expr = expr_copy(org->left.expr);
- break;
- case E_EQUAL:
- case E_GEQ:
- case E_GTH:
- case E_LEQ:
- case E_LTH:
- case E_UNEQUAL:
- e->left.sym = org->left.sym;
- e->right.sym = org->right.sym;
- break;
- case E_AND:
- case E_OR:
- e->left.expr = expr_copy(org->left.expr);
- e->right.expr = expr_copy(org->right.expr);
- break;
- default:
- fprintf(stderr, "can't copy type %d\n", e->type);
- free(e);
- e = NULL;
- break;
- }
-
- return e;
-}
-
-void expr_free(struct expr *e)
-{
- if (!e)
- return;
-
- switch (e->type) {
- case E_SYMBOL:
- break;
- case E_NOT:
- expr_free(e->left.expr);
- break;
- case E_EQUAL:
- case E_GEQ:
- case E_GTH:
- case E_LEQ:
- case E_LTH:
- case E_UNEQUAL:
- break;
- case E_OR:
- case E_AND:
- expr_free(e->left.expr);
- expr_free(e->right.expr);
- break;
- default:
- fprintf(stderr, "how to free type %d?\n", e->type);
- break;
- }
- free(e);
-}
-
static int trans_count;
/*
@@ -146,16 +99,24 @@ static int trans_count;
*/
static void __expr_eliminate_eq(enum expr_type type, struct expr **ep1, struct expr **ep2)
{
+ struct expr *l, *r;
+
/* Recurse down to leaves */
if ((*ep1)->type == type) {
- __expr_eliminate_eq(type, &(*ep1)->left.expr, ep2);
- __expr_eliminate_eq(type, &(*ep1)->right.expr, ep2);
+ l = (*ep1)->left.expr;
+ r = (*ep1)->right.expr;
+ __expr_eliminate_eq(type, &l, ep2);
+ __expr_eliminate_eq(type, &r, ep2);
+ *ep1 = expr_alloc_two(type, l, r);
return;
}
if ((*ep2)->type == type) {
- __expr_eliminate_eq(type, ep1, &(*ep2)->left.expr);
- __expr_eliminate_eq(type, ep1, &(*ep2)->right.expr);
+ l = (*ep2)->left.expr;
+ r = (*ep2)->right.expr;
+ __expr_eliminate_eq(type, ep1, &l);
+ __expr_eliminate_eq(type, ep1, &r);
+ *ep2 = expr_alloc_two(type, l, r);
return;
}
@@ -171,7 +132,6 @@ static void __expr_eliminate_eq(enum expr_type type, struct expr **ep1, struct e
/* *ep1 and *ep2 are equal leaves. Prepare them for elimination. */
trans_count++;
- expr_free(*ep1); expr_free(*ep2);
switch (type) {
case E_OR:
*ep1 = expr_alloc_symbol(&symbol_no);
@@ -271,14 +231,10 @@ bool expr_eq(struct expr *e1, struct expr *e2)
return expr_eq(e1->left.expr, e2->left.expr);
case E_AND:
case E_OR:
- e1 = expr_copy(e1);
- e2 = expr_copy(e2);
old_count = trans_count;
expr_eliminate_eq(&e1, &e2);
res = (e1->type == E_SYMBOL && e2->type == E_SYMBOL &&
e1->left.sym == e2->left.sym);
- expr_free(e1);
- expr_free(e2);
trans_count = old_count;
return res;
case E_RANGE:
@@ -297,7 +253,7 @@ bool expr_eq(struct expr *e1, struct expr *e2)
}
/*
- * Recursively performs the following simplifications in-place (as well as the
+ * Recursively performs the following simplifications (as well as the
* corresponding simplifications with swapped operands):
*
* expr && n -> n
@@ -309,79 +265,39 @@ bool expr_eq(struct expr *e1, struct expr *e2)
*/
static struct expr *expr_eliminate_yn(struct expr *e)
{
- struct expr *tmp;
+ struct expr *l, *r;
if (e) switch (e->type) {
case E_AND:
- e->left.expr = expr_eliminate_yn(e->left.expr);
- e->right.expr = expr_eliminate_yn(e->right.expr);
- if (e->left.expr->type == E_SYMBOL) {
- if (e->left.expr->left.sym == &symbol_no) {
- expr_free(e->left.expr);
- expr_free(e->right.expr);
- e->type = E_SYMBOL;
- e->left.sym = &symbol_no;
- e->right.expr = NULL;
- return e;
- } else if (e->left.expr->left.sym == &symbol_yes) {
- free(e->left.expr);
- tmp = e->right.expr;
- *e = *(e->right.expr);
- free(tmp);
- return e;
- }
+ l = expr_eliminate_yn(e->left.expr);
+ r = expr_eliminate_yn(e->right.expr);
+ if (l->type == E_SYMBOL) {
+ if (l->left.sym == &symbol_no)
+ return l;
+ else if (l->left.sym == &symbol_yes)
+ return r;
}
- if (e->right.expr->type == E_SYMBOL) {
- if (e->right.expr->left.sym == &symbol_no) {
- expr_free(e->left.expr);
- expr_free(e->right.expr);
- e->type = E_SYMBOL;
- e->left.sym = &symbol_no;
- e->right.expr = NULL;
- return e;
- } else if (e->right.expr->left.sym == &symbol_yes) {
- free(e->right.expr);
- tmp = e->left.expr;
- *e = *(e->left.expr);
- free(tmp);
- return e;
- }
+ if (r->type == E_SYMBOL) {
+ if (r->left.sym == &symbol_no)
+ return r;
+ else if (r->left.sym == &symbol_yes)
+ return l;
}
break;
case E_OR:
- e->left.expr = expr_eliminate_yn(e->left.expr);
- e->right.expr = expr_eliminate_yn(e->right.expr);
- if (e->left.expr->type == E_SYMBOL) {
- if (e->left.expr->left.sym == &symbol_no) {
- free(e->left.expr);
- tmp = e->right.expr;
- *e = *(e->right.expr);
- free(tmp);
- return e;
- } else if (e->left.expr->left.sym == &symbol_yes) {
- expr_free(e->left.expr);
- expr_free(e->right.expr);
- e->type = E_SYMBOL;
- e->left.sym = &symbol_yes;
- e->right.expr = NULL;
- return e;
- }
+ l = expr_eliminate_yn(e->left.expr);
+ r = expr_eliminate_yn(e->right.expr);
+ if (l->type == E_SYMBOL) {
+ if (l->left.sym == &symbol_no)
+ return r;
+ else if (l->left.sym == &symbol_yes)
+ return l;
}
- if (e->right.expr->type == E_SYMBOL) {
- if (e->right.expr->left.sym == &symbol_no) {
- free(e->right.expr);
- tmp = e->left.expr;
- *e = *(e->left.expr);
- free(tmp);
- return e;
- } else if (e->right.expr->left.sym == &symbol_yes) {
- expr_free(e->left.expr);
- expr_free(e->right.expr);
- e->type = E_SYMBOL;
- e->left.sym = &symbol_yes;
- e->right.expr = NULL;
- return e;
- }
+ if (r->type == E_SYMBOL) {
+ if (r->left.sym == &symbol_no)
+ return l;
+ else if (r->left.sym == &symbol_yes)
+ return r;
}
break;
default:
@@ -399,7 +315,7 @@ static struct expr *expr_join_or(struct expr *e1, struct expr *e2)
struct symbol *sym1, *sym2;
if (expr_eq(e1, e2))
- return expr_copy(e1);
+ return e1;
if (e1->type != E_EQUAL && e1->type != E_UNEQUAL && e1->type != E_SYMBOL && e1->type != E_NOT)
return NULL;
if (e2->type != E_EQUAL && e2->type != E_UNEQUAL && e2->type != E_SYMBOL && e2->type != E_NOT)
@@ -464,7 +380,7 @@ static struct expr *expr_join_and(struct expr *e1, struct expr *e2)
struct symbol *sym1, *sym2;
if (expr_eq(e1, e2))
- return expr_copy(e1);
+ return e1;
if (e1->type != E_EQUAL && e1->type != E_UNEQUAL && e1->type != E_SYMBOL && e1->type != E_NOT)
return NULL;
if (e2->type != E_EQUAL && e2->type != E_UNEQUAL && e2->type != E_SYMBOL && e2->type != E_NOT)
@@ -561,18 +477,24 @@ static struct expr *expr_join_and(struct expr *e1, struct expr *e2)
*/
static void expr_eliminate_dups1(enum expr_type type, struct expr **ep1, struct expr **ep2)
{
- struct expr *tmp;
+ struct expr *tmp, *l, *r;
/* Recurse down to leaves */
if ((*ep1)->type == type) {
- expr_eliminate_dups1(type, &(*ep1)->left.expr, ep2);
- expr_eliminate_dups1(type, &(*ep1)->right.expr, ep2);
+ l = (*ep1)->left.expr;
+ r = (*ep1)->right.expr;
+ expr_eliminate_dups1(type, &l, ep2);
+ expr_eliminate_dups1(type, &r, ep2);
+ *ep1 = expr_alloc_two(type, l, r);
return;
}
if ((*ep2)->type == type) {
- expr_eliminate_dups1(type, ep1, &(*ep2)->left.expr);
- expr_eliminate_dups1(type, ep1, &(*ep2)->right.expr);
+ l = (*ep2)->left.expr;
+ r = (*ep2)->right.expr;
+ expr_eliminate_dups1(type, ep1, &l);
+ expr_eliminate_dups1(type, ep1, &r);
+ *ep2 = expr_alloc_two(type, l, r);
return;
}
@@ -582,7 +504,6 @@ static void expr_eliminate_dups1(enum expr_type type, struct expr **ep1, struct
case E_OR:
tmp = expr_join_or(*ep1, *ep2);
if (tmp) {
- expr_free(*ep1); expr_free(*ep2);
*ep1 = expr_alloc_symbol(&symbol_no);
*ep2 = tmp;
trans_count++;
@@ -591,7 +512,6 @@ static void expr_eliminate_dups1(enum expr_type type, struct expr **ep1, struct
case E_AND:
tmp = expr_join_and(*ep1, *ep2);
if (tmp) {
- expr_free(*ep1); expr_free(*ep2);
*ep1 = expr_alloc_symbol(&symbol_yes);
*ep2 = tmp;
trans_count++;
@@ -621,12 +541,15 @@ struct expr *expr_eliminate_dups(struct expr *e)
oldcount = trans_count;
do {
+ struct expr *l, *r;
+
trans_count = 0;
switch (e->type) {
case E_OR: case E_AND:
- e->left.expr = expr_eliminate_dups(e->left.expr);
- e->right.expr = expr_eliminate_dups(e->right.expr);
- expr_eliminate_dups1(e->type, &e->left.expr, &e->right.expr);
+ l = expr_eliminate_dups(e->left.expr);
+ r = expr_eliminate_dups(e->right.expr);
+ expr_eliminate_dups1(e->type, &l, &r);
+ e = expr_alloc_two(e->type, l, r);
default:
;
}
@@ -668,8 +591,6 @@ struct expr *expr_eliminate_dups(struct expr *e)
*/
struct expr *expr_transform(struct expr *e)
{
- struct expr *tmp;
-
if (!e)
return NULL;
switch (e->type) {
@@ -682,8 +603,9 @@ struct expr *expr_transform(struct expr *e)
case E_SYMBOL:
break;
default:
- e->left.expr = expr_transform(e->left.expr);
- e->right.expr = expr_transform(e->right.expr);
+ e = expr_alloc_two(e->type,
+ expr_transform(e->left.expr),
+ expr_transform(e->right.expr));
}
switch (e->type) {
@@ -692,23 +614,18 @@ struct expr *expr_transform(struct expr *e)
break;
if (e->right.sym == &symbol_no) {
// A=n -> !A
- e->type = E_NOT;
- e->left.expr = expr_alloc_symbol(e->left.sym);
- e->right.sym = NULL;
+ e = expr_alloc_one(E_NOT, expr_alloc_symbol(e->left.sym));
break;
}
if (e->right.sym == &symbol_mod) {
// A=m -> n
printf("boolean symbol %s tested for 'm'? test forced to 'n'\n", e->left.sym->name);
- e->type = E_SYMBOL;
- e->left.sym = &symbol_no;
- e->right.sym = NULL;
+ e = expr_alloc_symbol(&symbol_no);
break;
}
if (e->right.sym == &symbol_yes) {
// A=y -> A
- e->type = E_SYMBOL;
- e->right.sym = NULL;
+ e = expr_alloc_symbol(e->left.sym);
break;
}
break;
@@ -717,23 +634,18 @@ struct expr *expr_transform(struct expr *e)
break;
if (e->right.sym == &symbol_no) {
// A!=n -> A
- e->type = E_SYMBOL;
- e->right.sym = NULL;
+ e = expr_alloc_symbol(e->left.sym);
break;
}
if (e->right.sym == &symbol_mod) {
// A!=m -> y
printf("boolean symbol %s tested for 'm'? test forced to 'y'\n", e->left.sym->name);
- e->type = E_SYMBOL;
- e->left.sym = &symbol_yes;
- e->right.sym = NULL;
+ e = expr_alloc_symbol(&symbol_yes);
break;
}
if (e->right.sym == &symbol_yes) {
// A!=y -> !A
- e->type = E_NOT;
- e->left.expr = expr_alloc_symbol(e->left.sym);
- e->right.sym = NULL;
+ e = expr_alloc_one(E_NOT, e->left.expr);
break;
}
break;
@@ -741,82 +653,51 @@ struct expr *expr_transform(struct expr *e)
switch (e->left.expr->type) {
case E_NOT:
// !!A -> A
- tmp = e->left.expr->left.expr;
- free(e->left.expr);
- free(e);
- e = tmp;
- e = expr_transform(e);
+ e = e->left.expr->left.expr;
break;
case E_EQUAL:
case E_UNEQUAL:
// !(A=B) -> A!=B
- tmp = e->left.expr;
- free(e);
- e = tmp;
- e->type = e->type == E_EQUAL ? E_UNEQUAL : E_EQUAL;
+ e = expr_alloc_comp(e->left.expr->type == E_EQUAL ? E_UNEQUAL : E_EQUAL,
+ e->left.expr->left.sym,
+ e->left.expr->right.sym);
break;
case E_LEQ:
case E_GEQ:
// !(A<=B) -> A>B
- tmp = e->left.expr;
- free(e);
- e = tmp;
- e->type = e->type == E_LEQ ? E_GTH : E_LTH;
+ e = expr_alloc_comp(e->left.expr->type == E_LEQ ? E_GTH : E_LTH,
+ e->left.expr->left.sym,
+ e->left.expr->right.sym);
break;
case E_LTH:
case E_GTH:
// !(A<B) -> A>=B
- tmp = e->left.expr;
- free(e);
- e = tmp;
- e->type = e->type == E_LTH ? E_GEQ : E_LEQ;
+ e = expr_alloc_comp(e->left.expr->type == E_LTH ? E_GEQ : E_LEQ,
+ e->left.expr->left.sym,
+ e->left.expr->right.sym);
break;
case E_OR:
// !(A || B) -> !A && !B
- tmp = e->left.expr;
- e->type = E_AND;
- e->right.expr = expr_alloc_one(E_NOT, tmp->right.expr);
- tmp->type = E_NOT;
- tmp->right.expr = NULL;
+ e = expr_alloc_and(expr_alloc_one(E_NOT, e->left.expr->left.expr),
+ expr_alloc_one(E_NOT, e->left.expr->right.expr));
e = expr_transform(e);
break;
case E_AND:
// !(A && B) -> !A || !B
- tmp = e->left.expr;
- e->type = E_OR;
- e->right.expr = expr_alloc_one(E_NOT, tmp->right.expr);
- tmp->type = E_NOT;
- tmp->right.expr = NULL;
+ e = expr_alloc_or(expr_alloc_one(E_NOT, e->left.expr->left.expr),
+ expr_alloc_one(E_NOT, e->left.expr->right.expr));
e = expr_transform(e);
break;
case E_SYMBOL:
- if (e->left.expr->left.sym == &symbol_yes) {
+ if (e->left.expr->left.sym == &symbol_yes)
// !'y' -> 'n'
- tmp = e->left.expr;
- free(e);
- e = tmp;
- e->type = E_SYMBOL;
- e->left.sym = &symbol_no;
- break;
- }
- if (e->left.expr->left.sym == &symbol_mod) {
+ e = expr_alloc_symbol(&symbol_no);
+ else if (e->left.expr->left.sym == &symbol_mod)
// !'m' -> 'm'
- tmp = e->left.expr;
- free(e);
- e = tmp;
- e->type = E_SYMBOL;
- e->left.sym = &symbol_mod;
- break;
- }
- if (e->left.expr->left.sym == &symbol_no) {
+ e = expr_alloc_symbol(&symbol_mod);
+ else if (e->left.expr->left.sym == &symbol_no)
// !'n' -> 'y'
- tmp = e->left.expr;
- free(e);
- e = tmp;
- e->type = E_SYMBOL;
- e->left.sym = &symbol_yes;
- break;
- }
+ e = expr_alloc_symbol(&symbol_yes);
break;
default:
;
@@ -940,18 +821,18 @@ struct expr *expr_trans_compare(struct expr *e, enum expr_type type, struct symb
case E_EQUAL:
if (type == E_EQUAL) {
if (sym == &symbol_yes)
- return expr_copy(e);
+ return e;
if (sym == &symbol_mod)
return expr_alloc_symbol(&symbol_no);
if (sym == &symbol_no)
- return expr_alloc_one(E_NOT, expr_copy(e));
+ return expr_alloc_one(E_NOT, e);
} else {
if (sym == &symbol_yes)
- return expr_alloc_one(E_NOT, expr_copy(e));
+ return expr_alloc_one(E_NOT, e);
if (sym == &symbol_mod)
return expr_alloc_symbol(&symbol_yes);
if (sym == &symbol_no)
- return expr_copy(e);
+ return e;
}
break;
case E_SYMBOL:
diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
index 4ab7422ddbd8..a398b2b2dbe0 100644
--- a/scripts/kconfig/expr.h
+++ b/scripts/kconfig/expr.h
@@ -29,11 +29,21 @@ enum expr_type {
};
union expr_data {
- struct expr *expr;
- struct symbol *sym;
+ struct expr * const expr;
+ struct symbol * const sym;
+ void *_initdata;
};
+/**
+ * struct expr - expression
+ *
+ * @node: link node for the hash table
+ * @type: expressoin type
+ * @left: left node
+ * @right: right node
+ */
struct expr {
+ struct hlist_node node;
enum expr_type type;
union expr_data left, right;
};
@@ -275,8 +285,6 @@ struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e
struct expr *expr_alloc_comp(enum expr_type type, struct symbol *s1, struct symbol *s2);
struct expr *expr_alloc_and(struct expr *e1, struct expr *e2);
struct expr *expr_alloc_or(struct expr *e1, struct expr *e2);
-struct expr *expr_copy(const struct expr *org);
-void expr_free(struct expr *e);
void expr_eliminate_eq(struct expr **ep1, struct expr **ep2);
bool expr_eq(struct expr *e1, struct expr *e2);
tristate expr_calc_value(struct expr *e);
diff --git a/scripts/kconfig/internal.h b/scripts/kconfig/internal.h
index 02106eb7815e..84c2ea0389fd 100644
--- a/scripts/kconfig/internal.h
+++ b/scripts/kconfig/internal.h
@@ -11,6 +11,10 @@ extern HASHTABLE_DECLARE(sym_hashtable, SYMBOL_HASHSIZE);
#define for_all_symbols(sym) \
hash_for_each(sym_hashtable, sym, node)
+#define EXPR_HASHSIZE (1U << 14)
+
+extern HASHTABLE_DECLARE(expr_hashtable, EXPR_HASHSIZE);
+
struct menu;
extern struct menu *current_menu, *current_entry;
diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c
index f61327fabead..4addd33749bb 100644
--- a/scripts/kconfig/menu.c
+++ b/scripts/kconfig/menu.c
@@ -107,12 +107,13 @@ static struct expr *rewrite_m(struct expr *e)
switch (e->type) {
case E_NOT:
- e->left.expr = rewrite_m(e->left.expr);
+ e = expr_alloc_one(E_NOT, rewrite_m(e->left.expr));
break;
case E_OR:
case E_AND:
- e->left.expr = rewrite_m(e->left.expr);
- e->right.expr = rewrite_m(e->right.expr);
+ e = expr_alloc_two(e->type,
+ rewrite_m(e->left.expr),
+ rewrite_m(e->right.expr));
break;
case E_SYMBOL:
/* change 'm' into 'm' && MODULES */
@@ -192,21 +193,11 @@ struct property *menu_add_prompt(enum prop_type type, const char *prompt,
struct menu *menu = current_entry;
while ((menu = menu->parent) != NULL) {
- struct expr *dup_expr;
if (!menu->visibility)
continue;
- /*
- * Do not add a reference to the menu's visibility
- * expression but use a copy of it. Otherwise the
- * expression reduction functions will modify
- * expressions that have multiple references which
- * can cause unwanted side effects.
- */
- dup_expr = expr_copy(menu->visibility);
-
prop->visible.expr = expr_alloc_and(prop->visible.expr,
- dup_expr);
+ menu->visibility);
}
}
@@ -322,7 +313,7 @@ static void _menu_finalize(struct menu *parent, bool inside_choice)
*/
basedep = rewrite_m(menu->dep);
basedep = expr_transform(basedep);
- basedep = expr_alloc_and(expr_copy(parent->dep), basedep);
+ basedep = expr_alloc_and(parent->dep, basedep);
basedep = expr_eliminate_dups(basedep);
menu->dep = basedep;
@@ -366,7 +357,7 @@ static void _menu_finalize(struct menu *parent, bool inside_choice)
*/
dep = rewrite_m(prop->visible.expr);
dep = expr_transform(dep);
- dep = expr_alloc_and(expr_copy(basedep), dep);
+ dep = expr_alloc_and(basedep, dep);
dep = expr_eliminate_dups(dep);
prop->visible.expr = dep;
@@ -377,11 +368,11 @@ static void _menu_finalize(struct menu *parent, bool inside_choice)
if (prop->type == P_SELECT) {
struct symbol *es = prop_get_symbol(prop);
es->rev_dep.expr = expr_alloc_or(es->rev_dep.expr,
- expr_alloc_and(expr_alloc_symbol(menu->sym), expr_copy(dep)));
+ expr_alloc_and(expr_alloc_symbol(menu->sym), dep));
} else if (prop->type == P_IMPLY) {
struct symbol *es = prop_get_symbol(prop);
es->implied.expr = expr_alloc_or(es->implied.expr,
- expr_alloc_and(expr_alloc_symbol(menu->sym), expr_copy(dep)));
+ expr_alloc_and(expr_alloc_symbol(menu->sym), dep));
}
}
}
@@ -441,22 +432,18 @@ static void _menu_finalize(struct menu *parent, bool inside_choice)
*/
dep = expr_trans_compare(dep, E_UNEQUAL, &symbol_no);
dep = expr_eliminate_dups(expr_transform(dep));
- dep2 = expr_copy(basedep);
+ dep2 = basedep;
expr_eliminate_eq(&dep, &dep2);
- expr_free(dep);
if (!expr_is_yes(dep2)) {
/* Not superset, quit */
- expr_free(dep2);
break;
}
/* Superset, put in submenu */
- expr_free(dep2);
next:
_menu_finalize(menu, false);
menu->parent = parent;
last_menu = menu;
}
- expr_free(basedep);
if (last_menu) {
parent->list = parent->next;
parent->next = last_menu->next;
--
2.43.0
