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Diffstat (limited to '')
| -rw-r--r-- | scripts/kconfig/expr.c | 1312 |
1 files changed, 1312 insertions, 0 deletions
diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c new file mode 100644 index 000000000..7e38070ee --- /dev/null +++ b/scripts/kconfig/expr.c @@ -0,0 +1,1312 @@ +/* + * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org> + * Released under the terms of the GNU GPL v2.0. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "lkc.h" + +#define DEBUG_EXPR 0 + +static int expr_eq(struct expr *e1, struct expr *e2); +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. + */ +static 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, + k_invalid +}; + +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; + case S_STRING: + case S_UNKNOWN: + val->s = strtoll(str, &tail, 0); + kind = k_signed; + break; + default: + return k_invalid; + } + 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_invalid || k2 == k_invalid) { + if (e->type != E_EQUAL && e->type != E_UNEQUAL) { + printf("Cannot compare \"%s\" and \"%s\"\n", str1, str2); + return no; + } + 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); +} |