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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /scripts/kconfig/expr.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'scripts/kconfig/expr.c')
-rw-r--r--scripts/kconfig/expr.c1303
1 files changed, 1303 insertions, 0 deletions
diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c
new file mode 100644
index 0000000000..81ebf8108c
--- /dev/null
+++ b/scripts/kconfig/expr.c
@@ -0,0 +1,1303 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
+ */
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lkc.h"
+
+#define DEBUG_EXPR 0
+
+static struct expr *expr_eliminate_yn(struct expr *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;
+}
+
+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;
+}
+
+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;
+}
+
+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;
+}
+
+struct expr *expr_alloc_and(struct expr *e1, struct expr *e2)
+{
+ if (!e1)
+ return e2;
+ return e2 ? expr_alloc_two(E_AND, e1, e2) : e1;
+}
+
+struct expr *expr_alloc_or(struct expr *e1, struct expr *e2)
+{
+ if (!e1)
+ return 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:
+ case E_LIST:
+ 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;
+
+#define e1 (*ep1)
+#define e2 (*ep2)
+
+/*
+ * expr_eliminate_eq() helper.
+ *
+ * Walks the two expression trees given in 'ep1' and 'ep2'. Any node that does
+ * not have type 'type' (E_OR/E_AND) is considered a leaf, and is compared
+ * against all other leaves. Two equal leaves are both replaced with either 'y'
+ * or 'n' as appropriate for 'type', to be eliminated later.
+ */
+static void __expr_eliminate_eq(enum expr_type type, struct expr **ep1, struct expr **ep2)
+{
+ /* Recurse down to leaves */
+
+ if (e1->type == type) {
+ __expr_eliminate_eq(type, &e1->left.expr, &e2);
+ __expr_eliminate_eq(type, &e1->right.expr, &e2);
+ return;
+ }
+ if (e2->type == type) {
+ __expr_eliminate_eq(type, &e1, &e2->left.expr);
+ __expr_eliminate_eq(type, &e1, &e2->right.expr);
+ return;
+ }
+
+ /* e1 and e2 are leaves. Compare them. */
+
+ if (e1->type == E_SYMBOL && e2->type == E_SYMBOL &&
+ e1->left.sym == e2->left.sym &&
+ (e1->left.sym == &symbol_yes || e1->left.sym == &symbol_no))
+ return;
+ if (!expr_eq(e1, e2))
+ return;
+
+ /* e1 and e2 are equal leaves. Prepare them for elimination. */
+
+ trans_count++;
+ expr_free(e1); expr_free(e2);
+ switch (type) {
+ case E_OR:
+ e1 = expr_alloc_symbol(&symbol_no);
+ e2 = expr_alloc_symbol(&symbol_no);
+ break;
+ case E_AND:
+ e1 = expr_alloc_symbol(&symbol_yes);
+ e2 = expr_alloc_symbol(&symbol_yes);
+ break;
+ default:
+ ;
+ }
+}
+
+/*
+ * Rewrites the expressions 'ep1' and 'ep2' to remove operands common to both.
+ * Example reductions:
+ *
+ * ep1: A && B -> ep1: y
+ * ep2: A && B && C -> ep2: C
+ *
+ * ep1: A || B -> ep1: n
+ * ep2: A || B || C -> ep2: C
+ *
+ * ep1: A && (B && FOO) -> ep1: FOO
+ * ep2: (BAR && B) && A -> ep2: BAR
+ *
+ * ep1: A && (B || C) -> ep1: y
+ * ep2: (C || B) && A -> ep2: y
+ *
+ * Comparisons are done between all operands at the same "level" of && or ||.
+ * For example, in the expression 'e1 && (e2 || e3) && (e4 || e5)', the
+ * following operands will be compared:
+ *
+ * - 'e1', 'e2 || e3', and 'e4 || e5', against each other
+ * - e2 against e3
+ * - e4 against e5
+ *
+ * Parentheses are irrelevant within a single level. 'e1 && (e2 && e3)' and
+ * '(e1 && e2) && e3' are both a single level.
+ *
+ * See __expr_eliminate_eq() as well.
+ */
+void expr_eliminate_eq(struct expr **ep1, struct expr **ep2)
+{
+ if (!e1 || !e2)
+ return;
+ switch (e1->type) {
+ case E_OR:
+ case E_AND:
+ __expr_eliminate_eq(e1->type, ep1, ep2);
+ default:
+ ;
+ }
+ if (e1->type != e2->type) switch (e2->type) {
+ case E_OR:
+ case E_AND:
+ __expr_eliminate_eq(e2->type, ep1, ep2);
+ default:
+ ;
+ }
+ e1 = expr_eliminate_yn(e1);
+ e2 = expr_eliminate_yn(e2);
+}
+
+#undef e1
+#undef e2
+
+/*
+ * Returns true if 'e1' and 'e2' are equal, after minor simplification. Two
+ * &&/|| expressions are considered equal if every operand in one expression
+ * equals some operand in the other (operands do not need to appear in the same
+ * order), recursively.
+ */
+int expr_eq(struct expr *e1, struct expr *e2)
+{
+ int res, old_count;
+
+ /*
+ * A NULL expr is taken to be yes, but there's also a different way to
+ * represent yes. expr_is_yes() checks for either representation.
+ */
+ if (!e1 || !e2)
+ return expr_is_yes(e1) && expr_is_yes(e2);
+
+ if (e1->type != e2->type)
+ return 0;
+ switch (e1->type) {
+ case E_EQUAL:
+ case E_GEQ:
+ case E_GTH:
+ case E_LEQ:
+ case E_LTH:
+ case E_UNEQUAL:
+ return e1->left.sym == e2->left.sym && e1->right.sym == e2->right.sym;
+ case E_SYMBOL:
+ return e1->left.sym == e2->left.sym;
+ case E_NOT:
+ 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_LIST:
+ case E_RANGE:
+ case E_NONE:
+ /* panic */;
+ }
+
+ if (DEBUG_EXPR) {
+ expr_fprint(e1, stdout);
+ printf(" = ");
+ expr_fprint(e2, stdout);
+ printf(" ?\n");
+ }
+
+ return 0;
+}
+
+/*
+ * Recursively performs the following simplifications in-place (as well as the
+ * corresponding simplifications with swapped operands):
+ *
+ * expr && n -> n
+ * expr && y -> expr
+ * expr || n -> expr
+ * expr || y -> y
+ *
+ * Returns the optimized expression.
+ */
+static struct expr *expr_eliminate_yn(struct expr *e)
+{
+ struct expr *tmp;
+
+ 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;
+ }
+ }
+ 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;
+ }
+ }
+ 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;
+ }
+ }
+ 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;
+ }
+ }
+ break;
+ default:
+ ;
+ }
+ return e;
+}
+
+/*
+ * bool FOO!=n => FOO
+ */
+struct expr *expr_trans_bool(struct expr *e)
+{
+ if (!e)
+ return NULL;
+ switch (e->type) {
+ case E_AND:
+ case E_OR:
+ case E_NOT:
+ e->left.expr = expr_trans_bool(e->left.expr);
+ e->right.expr = expr_trans_bool(e->right.expr);
+ break;
+ case E_UNEQUAL:
+ // FOO!=n -> FOO
+ if (e->left.sym->type == S_TRISTATE) {
+ if (e->right.sym == &symbol_no) {
+ e->type = E_SYMBOL;
+ e->right.sym = NULL;
+ }
+ }
+ break;
+ default:
+ ;
+ }
+ return e;
+}
+
+/*
+ * e1 || e2 -> ?
+ */
+static struct expr *expr_join_or(struct expr *e1, struct expr *e2)
+{
+ struct expr *tmp;
+ struct symbol *sym1, *sym2;
+
+ if (expr_eq(e1, e2))
+ return expr_copy(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)
+ return NULL;
+ if (e1->type == E_NOT) {
+ tmp = e1->left.expr;
+ if (tmp->type != E_EQUAL && tmp->type != E_UNEQUAL && tmp->type != E_SYMBOL)
+ return NULL;
+ sym1 = tmp->left.sym;
+ } else
+ sym1 = e1->left.sym;
+ if (e2->type == E_NOT) {
+ if (e2->left.expr->type != E_SYMBOL)
+ return NULL;
+ sym2 = e2->left.expr->left.sym;
+ } else
+ sym2 = e2->left.sym;
+ if (sym1 != sym2)
+ return NULL;
+ if (sym1->type != S_BOOLEAN && sym1->type != S_TRISTATE)
+ return NULL;
+ if (sym1->type == S_TRISTATE) {
+ if (e1->type == E_EQUAL && e2->type == E_EQUAL &&
+ ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_mod) ||
+ (e1->right.sym == &symbol_mod && e2->right.sym == &symbol_yes))) {
+ // (a='y') || (a='m') -> (a!='n')
+ return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_no);
+ }
+ if (e1->type == E_EQUAL && e2->type == E_EQUAL &&
+ ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_no) ||
+ (e1->right.sym == &symbol_no && e2->right.sym == &symbol_yes))) {
+ // (a='y') || (a='n') -> (a!='m')
+ return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_mod);
+ }
+ if (e1->type == E_EQUAL && e2->type == E_EQUAL &&
+ ((e1->right.sym == &symbol_mod && e2->right.sym == &symbol_no) ||
+ (e1->right.sym == &symbol_no && e2->right.sym == &symbol_mod))) {
+ // (a='m') || (a='n') -> (a!='y')
+ return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_yes);
+ }
+ }
+ if (sym1->type == S_BOOLEAN && sym1 == sym2) {
+ if ((e1->type == E_NOT && e1->left.expr->type == E_SYMBOL && e2->type == E_SYMBOL) ||
+ (e2->type == E_NOT && e2->left.expr->type == E_SYMBOL && e1->type == E_SYMBOL))
+ return expr_alloc_symbol(&symbol_yes);
+ }
+
+ if (DEBUG_EXPR) {
+ printf("optimize (");
+ expr_fprint(e1, stdout);
+ printf(") || (");
+ expr_fprint(e2, stdout);
+ printf(")?\n");
+ }
+ return NULL;
+}
+
+static struct expr *expr_join_and(struct expr *e1, struct expr *e2)
+{
+ struct expr *tmp;
+ struct symbol *sym1, *sym2;
+
+ if (expr_eq(e1, e2))
+ return expr_copy(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)
+ return NULL;
+ if (e1->type == E_NOT) {
+ tmp = e1->left.expr;
+ if (tmp->type != E_EQUAL && tmp->type != E_UNEQUAL && tmp->type != E_SYMBOL)
+ return NULL;
+ sym1 = tmp->left.sym;
+ } else
+ sym1 = e1->left.sym;
+ if (e2->type == E_NOT) {
+ if (e2->left.expr->type != E_SYMBOL)
+ return NULL;
+ sym2 = e2->left.expr->left.sym;
+ } else
+ sym2 = e2->left.sym;
+ if (sym1 != sym2)
+ return NULL;
+ if (sym1->type != S_BOOLEAN && sym1->type != S_TRISTATE)
+ return NULL;
+
+ if ((e1->type == E_SYMBOL && e2->type == E_EQUAL && e2->right.sym == &symbol_yes) ||
+ (e2->type == E_SYMBOL && e1->type == E_EQUAL && e1->right.sym == &symbol_yes))
+ // (a) && (a='y') -> (a='y')
+ return expr_alloc_comp(E_EQUAL, sym1, &symbol_yes);
+
+ if ((e1->type == E_SYMBOL && e2->type == E_UNEQUAL && e2->right.sym == &symbol_no) ||
+ (e2->type == E_SYMBOL && e1->type == E_UNEQUAL && e1->right.sym == &symbol_no))
+ // (a) && (a!='n') -> (a)
+ return expr_alloc_symbol(sym1);
+
+ if ((e1->type == E_SYMBOL && e2->type == E_UNEQUAL && e2->right.sym == &symbol_mod) ||
+ (e2->type == E_SYMBOL && e1->type == E_UNEQUAL && e1->right.sym == &symbol_mod))
+ // (a) && (a!='m') -> (a='y')
+ return expr_alloc_comp(E_EQUAL, sym1, &symbol_yes);
+
+ if (sym1->type == S_TRISTATE) {
+ if (e1->type == E_EQUAL && e2->type == E_UNEQUAL) {
+ // (a='b') && (a!='c') -> 'b'='c' ? 'n' : a='b'
+ sym2 = e1->right.sym;
+ if ((e2->right.sym->flags & SYMBOL_CONST) && (sym2->flags & SYMBOL_CONST))
+ return sym2 != e2->right.sym ? expr_alloc_comp(E_EQUAL, sym1, sym2)
+ : expr_alloc_symbol(&symbol_no);
+ }
+ if (e1->type == E_UNEQUAL && e2->type == E_EQUAL) {
+ // (a='b') && (a!='c') -> 'b'='c' ? 'n' : a='b'
+ sym2 = e2->right.sym;
+ if ((e1->right.sym->flags & SYMBOL_CONST) && (sym2->flags & SYMBOL_CONST))
+ return sym2 != e1->right.sym ? expr_alloc_comp(E_EQUAL, sym1, sym2)
+ : expr_alloc_symbol(&symbol_no);
+ }
+ if (e1->type == E_UNEQUAL && e2->type == E_UNEQUAL &&
+ ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_no) ||
+ (e1->right.sym == &symbol_no && e2->right.sym == &symbol_yes)))
+ // (a!='y') && (a!='n') -> (a='m')
+ return expr_alloc_comp(E_EQUAL, sym1, &symbol_mod);
+
+ if (e1->type == E_UNEQUAL && e2->type == E_UNEQUAL &&
+ ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_mod) ||
+ (e1->right.sym == &symbol_mod && e2->right.sym == &symbol_yes)))
+ // (a!='y') && (a!='m') -> (a='n')
+ return expr_alloc_comp(E_EQUAL, sym1, &symbol_no);
+
+ if (e1->type == E_UNEQUAL && e2->type == E_UNEQUAL &&
+ ((e1->right.sym == &symbol_mod && e2->right.sym == &symbol_no) ||
+ (e1->right.sym == &symbol_no && e2->right.sym == &symbol_mod)))
+ // (a!='m') && (a!='n') -> (a='m')
+ return expr_alloc_comp(E_EQUAL, sym1, &symbol_yes);
+
+ if ((e1->type == E_SYMBOL && e2->type == E_EQUAL && e2->right.sym == &symbol_mod) ||
+ (e2->type == E_SYMBOL && e1->type == E_EQUAL && e1->right.sym == &symbol_mod) ||
+ (e1->type == E_SYMBOL && e2->type == E_UNEQUAL && e2->right.sym == &symbol_yes) ||
+ (e2->type == E_SYMBOL && e1->type == E_UNEQUAL && e1->right.sym == &symbol_yes))
+ return NULL;
+ }
+
+ if (DEBUG_EXPR) {
+ printf("optimize (");
+ expr_fprint(e1, stdout);
+ printf(") && (");
+ expr_fprint(e2, stdout);
+ printf(")?\n");
+ }
+ return NULL;
+}
+
+/*
+ * expr_eliminate_dups() helper.
+ *
+ * Walks the two expression trees given in 'ep1' and 'ep2'. Any node that does
+ * not have type 'type' (E_OR/E_AND) is considered a leaf, and is compared
+ * against all other leaves to look for simplifications.
+ */
+static void expr_eliminate_dups1(enum expr_type type, struct expr **ep1, struct expr **ep2)
+{
+#define e1 (*ep1)
+#define e2 (*ep2)
+ struct expr *tmp;
+
+ /* Recurse down to leaves */
+
+ if (e1->type == type) {
+ expr_eliminate_dups1(type, &e1->left.expr, &e2);
+ expr_eliminate_dups1(type, &e1->right.expr, &e2);
+ return;
+ }
+ if (e2->type == type) {
+ expr_eliminate_dups1(type, &e1, &e2->left.expr);
+ expr_eliminate_dups1(type, &e1, &e2->right.expr);
+ return;
+ }
+
+ /* e1 and e2 are leaves. Compare and process them. */
+
+ if (e1 == e2)
+ return;
+
+ switch (e1->type) {
+ case E_OR: case E_AND:
+ expr_eliminate_dups1(e1->type, &e1, &e1);
+ default:
+ ;
+ }
+
+ switch (type) {
+ case E_OR:
+ tmp = expr_join_or(e1, e2);
+ if (tmp) {
+ expr_free(e1); expr_free(e2);
+ e1 = expr_alloc_symbol(&symbol_no);
+ e2 = tmp;
+ trans_count++;
+ }
+ break;
+ case E_AND:
+ tmp = expr_join_and(e1, e2);
+ if (tmp) {
+ expr_free(e1); expr_free(e2);
+ e1 = expr_alloc_symbol(&symbol_yes);
+ e2 = tmp;
+ trans_count++;
+ }
+ break;
+ default:
+ ;
+ }
+#undef e1
+#undef e2
+}
+
+/*
+ * Rewrites 'e' in-place to remove ("join") duplicate and other redundant
+ * operands.
+ *
+ * Example simplifications:
+ *
+ * A || B || A -> A || B
+ * A && B && A=y -> A=y && B
+ *
+ * Returns the deduplicated expression.
+ */
+struct expr *expr_eliminate_dups(struct expr *e)
+{
+ int oldcount;
+ if (!e)
+ return e;
+
+ oldcount = trans_count;
+ while (1) {
+ trans_count = 0;
+ switch (e->type) {
+ case E_OR: case E_AND:
+ expr_eliminate_dups1(e->type, &e, &e);
+ default:
+ ;
+ }
+ if (!trans_count)
+ /* No simplifications done in this pass. We're done */
+ break;
+ e = expr_eliminate_yn(e);
+ }
+ trans_count = oldcount;
+ return e;
+}
+
+/*
+ * Performs various simplifications involving logical operators and
+ * comparisons.
+ *
+ * Allocates and returns a new expression.
+ */
+struct expr *expr_transform(struct expr *e)
+{
+ struct expr *tmp;
+
+ if (!e)
+ return NULL;
+ switch (e->type) {
+ case E_EQUAL:
+ case E_GEQ:
+ case E_GTH:
+ case E_LEQ:
+ case E_LTH:
+ case E_UNEQUAL:
+ case E_SYMBOL:
+ case E_LIST:
+ break;
+ default:
+ e->left.expr = expr_transform(e->left.expr);
+ e->right.expr = expr_transform(e->right.expr);
+ }
+
+ switch (e->type) {
+ case E_EQUAL:
+ if (e->left.sym->type != S_BOOLEAN)
+ break;
+ if (e->right.sym == &symbol_no) {
+ e->type = E_NOT;
+ e->left.expr = expr_alloc_symbol(e->left.sym);
+ e->right.sym = NULL;
+ break;
+ }
+ if (e->right.sym == &symbol_mod) {
+ 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;
+ break;
+ }
+ if (e->right.sym == &symbol_yes) {
+ e->type = E_SYMBOL;
+ e->right.sym = NULL;
+ break;
+ }
+ break;
+ case E_UNEQUAL:
+ if (e->left.sym->type != S_BOOLEAN)
+ break;
+ if (e->right.sym == &symbol_no) {
+ e->type = E_SYMBOL;
+ e->right.sym = NULL;
+ break;
+ }
+ if (e->right.sym == &symbol_mod) {
+ 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;
+ break;
+ }
+ if (e->right.sym == &symbol_yes) {
+ e->type = E_NOT;
+ e->left.expr = expr_alloc_symbol(e->left.sym);
+ e->right.sym = NULL;
+ break;
+ }
+ break;
+ case E_NOT:
+ 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);
+ break;
+ case E_EQUAL:
+ case E_UNEQUAL:
+ // !a='x' -> a!='x'
+ tmp = e->left.expr;
+ free(e);
+ e = tmp;
+ e->type = e->type == E_EQUAL ? E_UNEQUAL : E_EQUAL;
+ break;
+ case E_LEQ:
+ case E_GEQ:
+ // !a<='x' -> a>'x'
+ tmp = e->left.expr;
+ free(e);
+ e = tmp;
+ e->type = e->type == E_LEQ ? E_GTH : E_LTH;
+ break;
+ case E_LTH:
+ case E_GTH:
+ // !a<'x' -> a>='x'
+ tmp = e->left.expr;
+ free(e);
+ e = tmp;
+ e->type = e->type == E_LTH ? E_GEQ : E_LEQ;
+ 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_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_transform(e);
+ break;
+ case E_SYMBOL:
+ 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) {
+ // !'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) {
+ // !'n' -> 'y'
+ tmp = e->left.expr;
+ free(e);
+ e = tmp;
+ e->type = E_SYMBOL;
+ e->left.sym = &symbol_yes;
+ break;
+ }
+ break;
+ default:
+ ;
+ }
+ break;
+ default:
+ ;
+ }
+ return e;
+}
+
+int expr_contains_symbol(struct expr *dep, struct symbol *sym)
+{
+ if (!dep)
+ return 0;
+
+ switch (dep->type) {
+ case E_AND:
+ case E_OR:
+ return expr_contains_symbol(dep->left.expr, sym) ||
+ expr_contains_symbol(dep->right.expr, sym);
+ case E_SYMBOL:
+ return dep->left.sym == sym;
+ case E_EQUAL:
+ case E_GEQ:
+ case E_GTH:
+ case E_LEQ:
+ case E_LTH:
+ case E_UNEQUAL:
+ return dep->left.sym == sym ||
+ dep->right.sym == sym;
+ case E_NOT:
+ return expr_contains_symbol(dep->left.expr, sym);
+ default:
+ ;
+ }
+ return 0;
+}
+
+bool expr_depends_symbol(struct expr *dep, struct symbol *sym)
+{
+ if (!dep)
+ return false;
+
+ switch (dep->type) {
+ case E_AND:
+ return expr_depends_symbol(dep->left.expr, sym) ||
+ expr_depends_symbol(dep->right.expr, sym);
+ case E_SYMBOL:
+ return dep->left.sym == sym;
+ case E_EQUAL:
+ if (dep->left.sym == sym) {
+ if (dep->right.sym == &symbol_yes || dep->right.sym == &symbol_mod)
+ return true;
+ }
+ break;
+ case E_UNEQUAL:
+ if (dep->left.sym == sym) {
+ if (dep->right.sym == &symbol_no)
+ return true;
+ }
+ break;
+ default:
+ ;
+ }
+ return false;
+}
+
+/*
+ * Inserts explicit comparisons of type 'type' to symbol 'sym' into the
+ * expression 'e'.
+ *
+ * Examples transformations for type == E_UNEQUAL, sym == &symbol_no:
+ *
+ * A -> A!=n
+ * !A -> A=n
+ * A && B -> !(A=n || B=n)
+ * A || B -> !(A=n && B=n)
+ * A && (B || C) -> !(A=n || (B=n && C=n))
+ *
+ * Allocates and returns a new expression.
+ */
+struct expr *expr_trans_compare(struct expr *e, enum expr_type type, struct symbol *sym)
+{
+ struct expr *e1, *e2;
+
+ if (!e) {
+ e = expr_alloc_symbol(sym);
+ if (type == E_UNEQUAL)
+ e = expr_alloc_one(E_NOT, e);
+ return e;
+ }
+ switch (e->type) {
+ case E_AND:
+ e1 = expr_trans_compare(e->left.expr, E_EQUAL, sym);
+ e2 = expr_trans_compare(e->right.expr, E_EQUAL, sym);
+ if (sym == &symbol_yes)
+ e = expr_alloc_two(E_AND, e1, e2);
+ if (sym == &symbol_no)
+ e = expr_alloc_two(E_OR, e1, e2);
+ if (type == E_UNEQUAL)
+ e = expr_alloc_one(E_NOT, e);
+ return e;
+ case E_OR:
+ e1 = expr_trans_compare(e->left.expr, E_EQUAL, sym);
+ e2 = expr_trans_compare(e->right.expr, E_EQUAL, sym);
+ if (sym == &symbol_yes)
+ e = expr_alloc_two(E_OR, e1, e2);
+ if (sym == &symbol_no)
+ e = expr_alloc_two(E_AND, e1, e2);
+ if (type == E_UNEQUAL)
+ e = expr_alloc_one(E_NOT, e);
+ return e;
+ case E_NOT:
+ return expr_trans_compare(e->left.expr, type == E_EQUAL ? E_UNEQUAL : E_EQUAL, sym);
+ case E_UNEQUAL:
+ case E_LTH:
+ case E_LEQ:
+ case E_GTH:
+ case E_GEQ:
+ case E_EQUAL:
+ if (type == E_EQUAL) {
+ if (sym == &symbol_yes)
+ return expr_copy(e);
+ if (sym == &symbol_mod)
+ return expr_alloc_symbol(&symbol_no);
+ if (sym == &symbol_no)
+ return expr_alloc_one(E_NOT, expr_copy(e));
+ } else {
+ if (sym == &symbol_yes)
+ return expr_alloc_one(E_NOT, expr_copy(e));
+ if (sym == &symbol_mod)
+ return expr_alloc_symbol(&symbol_yes);
+ if (sym == &symbol_no)
+ return expr_copy(e);
+ }
+ break;
+ case E_SYMBOL:
+ return expr_alloc_comp(type, e->left.sym, sym);
+ case E_LIST:
+ case E_RANGE:
+ case E_NONE:
+ /* panic */;
+ }
+ return NULL;
+}
+
+enum string_value_kind {
+ k_string,
+ k_signed,
+ k_unsigned,
+};
+
+union string_value {
+ unsigned long long u;
+ signed long long s;
+};
+
+static enum string_value_kind expr_parse_string(const char *str,
+ enum symbol_type type,
+ union string_value *val)
+{
+ char *tail;
+ enum string_value_kind kind;
+
+ errno = 0;
+ switch (type) {
+ case S_BOOLEAN:
+ case S_TRISTATE:
+ val->s = !strcmp(str, "n") ? 0 :
+ !strcmp(str, "m") ? 1 :
+ !strcmp(str, "y") ? 2 : -1;
+ return k_signed;
+ case S_INT:
+ val->s = strtoll(str, &tail, 10);
+ kind = k_signed;
+ break;
+ case S_HEX:
+ val->u = strtoull(str, &tail, 16);
+ kind = k_unsigned;
+ break;
+ default:
+ val->s = strtoll(str, &tail, 0);
+ kind = k_signed;
+ break;
+ }
+ return !errno && !*tail && tail > str && isxdigit(tail[-1])
+ ? kind : k_string;
+}
+
+tristate expr_calc_value(struct expr *e)
+{
+ tristate val1, val2;
+ const char *str1, *str2;
+ enum string_value_kind k1 = k_string, k2 = k_string;
+ union string_value lval = {}, rval = {};
+ int res;
+
+ if (!e)
+ return yes;
+
+ switch (e->type) {
+ case E_SYMBOL:
+ sym_calc_value(e->left.sym);
+ return e->left.sym->curr.tri;
+ case E_AND:
+ val1 = expr_calc_value(e->left.expr);
+ val2 = expr_calc_value(e->right.expr);
+ return EXPR_AND(val1, val2);
+ case E_OR:
+ val1 = expr_calc_value(e->left.expr);
+ val2 = expr_calc_value(e->right.expr);
+ return EXPR_OR(val1, val2);
+ case E_NOT:
+ val1 = expr_calc_value(e->left.expr);
+ return EXPR_NOT(val1);
+ case E_EQUAL:
+ case E_GEQ:
+ case E_GTH:
+ case E_LEQ:
+ case E_LTH:
+ case E_UNEQUAL:
+ break;
+ default:
+ printf("expr_calc_value: %d?\n", e->type);
+ return no;
+ }
+
+ sym_calc_value(e->left.sym);
+ sym_calc_value(e->right.sym);
+ str1 = sym_get_string_value(e->left.sym);
+ str2 = sym_get_string_value(e->right.sym);
+
+ if (e->left.sym->type != S_STRING || e->right.sym->type != S_STRING) {
+ k1 = expr_parse_string(str1, e->left.sym->type, &lval);
+ k2 = expr_parse_string(str2, e->right.sym->type, &rval);
+ }
+
+ if (k1 == k_string || k2 == k_string)
+ res = strcmp(str1, str2);
+ else if (k1 == k_unsigned || k2 == k_unsigned)
+ res = (lval.u > rval.u) - (lval.u < rval.u);
+ else /* if (k1 == k_signed && k2 == k_signed) */
+ res = (lval.s > rval.s) - (lval.s < rval.s);
+
+ switch(e->type) {
+ case E_EQUAL:
+ return res ? no : yes;
+ case E_GEQ:
+ return res >= 0 ? yes : no;
+ case E_GTH:
+ return res > 0 ? yes : no;
+ case E_LEQ:
+ return res <= 0 ? yes : no;
+ case E_LTH:
+ return res < 0 ? yes : no;
+ case E_UNEQUAL:
+ return res ? yes : no;
+ default:
+ printf("expr_calc_value: relation %d?\n", e->type);
+ return no;
+ }
+}
+
+static int expr_compare_type(enum expr_type t1, enum expr_type t2)
+{
+ if (t1 == t2)
+ return 0;
+ switch (t1) {
+ case E_LEQ:
+ case E_LTH:
+ case E_GEQ:
+ case E_GTH:
+ if (t2 == E_EQUAL || t2 == E_UNEQUAL)
+ return 1;
+ case E_EQUAL:
+ case E_UNEQUAL:
+ if (t2 == E_NOT)
+ return 1;
+ case E_NOT:
+ if (t2 == E_AND)
+ return 1;
+ case E_AND:
+ if (t2 == E_OR)
+ return 1;
+ case E_OR:
+ if (t2 == E_LIST)
+ return 1;
+ case E_LIST:
+ if (t2 == 0)
+ return 1;
+ default:
+ return -1;
+ }
+ printf("[%dgt%d?]", t1, t2);
+ return 0;
+}
+
+void expr_print(struct expr *e,
+ void (*fn)(void *, struct symbol *, const char *),
+ void *data, int prevtoken)
+{
+ if (!e) {
+ fn(data, NULL, "y");
+ return;
+ }
+
+ if (expr_compare_type(prevtoken, e->type) > 0)
+ fn(data, NULL, "(");
+ switch (e->type) {
+ case E_SYMBOL:
+ if (e->left.sym->name)
+ fn(data, e->left.sym, e->left.sym->name);
+ else
+ fn(data, NULL, "<choice>");
+ break;
+ case E_NOT:
+ fn(data, NULL, "!");
+ expr_print(e->left.expr, fn, data, E_NOT);
+ break;
+ case E_EQUAL:
+ if (e->left.sym->name)
+ fn(data, e->left.sym, e->left.sym->name);
+ else
+ fn(data, NULL, "<choice>");
+ fn(data, NULL, "=");
+ fn(data, e->right.sym, e->right.sym->name);
+ break;
+ case E_LEQ:
+ case E_LTH:
+ if (e->left.sym->name)
+ fn(data, e->left.sym, e->left.sym->name);
+ else
+ fn(data, NULL, "<choice>");
+ fn(data, NULL, e->type == E_LEQ ? "<=" : "<");
+ fn(data, e->right.sym, e->right.sym->name);
+ break;
+ case E_GEQ:
+ case E_GTH:
+ if (e->left.sym->name)
+ fn(data, e->left.sym, e->left.sym->name);
+ else
+ fn(data, NULL, "<choice>");
+ fn(data, NULL, e->type == E_GEQ ? ">=" : ">");
+ fn(data, e->right.sym, e->right.sym->name);
+ break;
+ case E_UNEQUAL:
+ if (e->left.sym->name)
+ fn(data, e->left.sym, e->left.sym->name);
+ else
+ fn(data, NULL, "<choice>");
+ fn(data, NULL, "!=");
+ fn(data, e->right.sym, e->right.sym->name);
+ break;
+ case E_OR:
+ expr_print(e->left.expr, fn, data, E_OR);
+ fn(data, NULL, " || ");
+ expr_print(e->right.expr, fn, data, E_OR);
+ break;
+ case E_AND:
+ expr_print(e->left.expr, fn, data, E_AND);
+ fn(data, NULL, " && ");
+ expr_print(e->right.expr, fn, data, E_AND);
+ break;
+ case E_LIST:
+ fn(data, e->right.sym, e->right.sym->name);
+ if (e->left.expr) {
+ fn(data, NULL, " ^ ");
+ expr_print(e->left.expr, fn, data, E_LIST);
+ }
+ break;
+ case E_RANGE:
+ fn(data, NULL, "[");
+ fn(data, e->left.sym, e->left.sym->name);
+ fn(data, NULL, " ");
+ fn(data, e->right.sym, e->right.sym->name);
+ fn(data, NULL, "]");
+ break;
+ default:
+ {
+ char buf[32];
+ sprintf(buf, "<unknown type %d>", e->type);
+ fn(data, NULL, buf);
+ break;
+ }
+ }
+ if (expr_compare_type(prevtoken, e->type) > 0)
+ fn(data, NULL, ")");
+}
+
+static void expr_print_file_helper(void *data, struct symbol *sym, const char *str)
+{
+ xfwrite(str, strlen(str), 1, data);
+}
+
+void expr_fprint(struct expr *e, FILE *out)
+{
+ expr_print(e, expr_print_file_helper, out, E_NONE);
+}
+
+static void expr_print_gstr_helper(void *data, struct symbol *sym, const char *str)
+{
+ struct gstr *gs = (struct gstr*)data;
+ const char *sym_str = NULL;
+
+ if (sym)
+ sym_str = sym_get_string_value(sym);
+
+ if (gs->max_width) {
+ unsigned extra_length = strlen(str);
+ const char *last_cr = strrchr(gs->s, '\n');
+ unsigned last_line_length;
+
+ if (sym_str)
+ extra_length += 4 + strlen(sym_str);
+
+ if (!last_cr)
+ last_cr = gs->s;
+
+ last_line_length = strlen(gs->s) - (last_cr - gs->s);
+
+ if ((last_line_length + extra_length) > gs->max_width)
+ str_append(gs, "\\\n");
+ }
+
+ str_append(gs, str);
+ if (sym && sym->type != S_UNKNOWN)
+ str_printf(gs, " [=%s]", sym_str);
+}
+
+void expr_gstr_print(struct expr *e, struct gstr *gs)
+{
+ expr_print(e, expr_print_gstr_helper, gs, E_NONE);
+}
+
+/*
+ * Transform the top level "||" tokens into newlines and prepend each
+ * line with a minus. This makes expressions much easier to read.
+ * Suitable for reverse dependency expressions.
+ */
+static void expr_print_revdep(struct expr *e,
+ void (*fn)(void *, struct symbol *, const char *),
+ void *data, tristate pr_type, const char **title)
+{
+ if (e->type == E_OR) {
+ expr_print_revdep(e->left.expr, fn, data, pr_type, title);
+ expr_print_revdep(e->right.expr, fn, data, pr_type, title);
+ } else if (expr_calc_value(e) == pr_type) {
+ if (*title) {
+ fn(data, NULL, *title);
+ *title = NULL;
+ }
+
+ fn(data, NULL, " - ");
+ expr_print(e, fn, data, E_NONE);
+ fn(data, NULL, "\n");
+ }
+}
+
+void expr_gstr_print_revdep(struct expr *e, struct gstr *gs,
+ tristate pr_type, const char *title)
+{
+ expr_print_revdep(e, expr_print_gstr_helper, gs, pr_type, &title);
+}