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1303 lines
30 KiB
1303 lines
30 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Copyright (C) 2002 Roman Zippel <[email protected]> |
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*/ |
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#include <ctype.h> |
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#include <errno.h> |
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#include "lkc.h" |
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#define DEBUG_EXPR 0 |
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static struct expr *expr_eliminate_yn(struct expr *e); |
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struct expr *expr_alloc_symbol(struct symbol *sym) |
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{ |
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struct expr *e = xcalloc(1, sizeof(*e)); |
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e->type = E_SYMBOL; |
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e->left.sym = sym; |
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return e; |
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} |
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struct expr *expr_alloc_one(enum expr_type type, struct expr *ce) |
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{ |
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struct expr *e = xcalloc(1, sizeof(*e)); |
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e->type = type; |
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e->left.expr = ce; |
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return e; |
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} |
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struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e2) |
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{ |
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struct expr *e = xcalloc(1, sizeof(*e)); |
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e->type = type; |
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e->left.expr = e1; |
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e->right.expr = e2; |
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return e; |
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} |
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struct expr *expr_alloc_comp(enum expr_type type, struct symbol *s1, struct symbol *s2) |
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{ |
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struct expr *e = xcalloc(1, sizeof(*e)); |
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e->type = type; |
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e->left.sym = s1; |
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e->right.sym = s2; |
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return e; |
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} |
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struct expr *expr_alloc_and(struct expr *e1, struct expr *e2) |
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{ |
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if (!e1) |
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return e2; |
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return e2 ? expr_alloc_two(E_AND, e1, e2) : e1; |
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} |
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struct expr *expr_alloc_or(struct expr *e1, struct expr *e2) |
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{ |
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if (!e1) |
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return e2; |
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return e2 ? expr_alloc_two(E_OR, e1, e2) : e1; |
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} |
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struct expr *expr_copy(const struct expr *org) |
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{ |
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struct expr *e; |
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if (!org) |
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return NULL; |
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e = xmalloc(sizeof(*org)); |
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memcpy(e, org, sizeof(*org)); |
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switch (org->type) { |
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case E_SYMBOL: |
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e->left = org->left; |
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break; |
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case E_NOT: |
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e->left.expr = expr_copy(org->left.expr); |
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break; |
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case E_EQUAL: |
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case E_GEQ: |
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case E_GTH: |
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case E_LEQ: |
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case E_LTH: |
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case E_UNEQUAL: |
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e->left.sym = org->left.sym; |
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e->right.sym = org->right.sym; |
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break; |
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case E_AND: |
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case E_OR: |
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case E_LIST: |
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e->left.expr = expr_copy(org->left.expr); |
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e->right.expr = expr_copy(org->right.expr); |
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break; |
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default: |
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fprintf(stderr, "can't copy type %d\n", e->type); |
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free(e); |
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e = NULL; |
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break; |
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} |
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return e; |
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} |
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void expr_free(struct expr *e) |
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{ |
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if (!e) |
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return; |
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switch (e->type) { |
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case E_SYMBOL: |
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break; |
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case E_NOT: |
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expr_free(e->left.expr); |
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break; |
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case E_EQUAL: |
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case E_GEQ: |
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case E_GTH: |
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case E_LEQ: |
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case E_LTH: |
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case E_UNEQUAL: |
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break; |
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case E_OR: |
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case E_AND: |
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expr_free(e->left.expr); |
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expr_free(e->right.expr); |
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break; |
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default: |
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fprintf(stderr, "how to free type %d?\n", e->type); |
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break; |
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} |
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free(e); |
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} |
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static int trans_count; |
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#define e1 (*ep1) |
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#define e2 (*ep2) |
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/* |
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* expr_eliminate_eq() helper. |
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* |
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* Walks the two expression trees given in 'ep1' and 'ep2'. Any node that does |
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* not have type 'type' (E_OR/E_AND) is considered a leaf, and is compared |
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* against all other leaves. Two equal leaves are both replaced with either 'y' |
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* or 'n' as appropriate for 'type', to be eliminated later. |
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*/ |
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static void __expr_eliminate_eq(enum expr_type type, struct expr **ep1, struct expr **ep2) |
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{ |
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/* Recurse down to leaves */ |
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if (e1->type == type) { |
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__expr_eliminate_eq(type, &e1->left.expr, &e2); |
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__expr_eliminate_eq(type, &e1->right.expr, &e2); |
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return; |
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} |
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if (e2->type == type) { |
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__expr_eliminate_eq(type, &e1, &e2->left.expr); |
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__expr_eliminate_eq(type, &e1, &e2->right.expr); |
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return; |
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} |
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/* e1 and e2 are leaves. Compare them. */ |
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if (e1->type == E_SYMBOL && e2->type == E_SYMBOL && |
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e1->left.sym == e2->left.sym && |
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(e1->left.sym == &symbol_yes || e1->left.sym == &symbol_no)) |
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return; |
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if (!expr_eq(e1, e2)) |
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return; |
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/* e1 and e2 are equal leaves. Prepare them for elimination. */ |
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trans_count++; |
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expr_free(e1); expr_free(e2); |
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switch (type) { |
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case E_OR: |
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e1 = expr_alloc_symbol(&symbol_no); |
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e2 = expr_alloc_symbol(&symbol_no); |
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break; |
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case E_AND: |
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e1 = expr_alloc_symbol(&symbol_yes); |
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e2 = expr_alloc_symbol(&symbol_yes); |
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break; |
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default: |
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; |
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} |
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} |
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/* |
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* Rewrites the expressions 'ep1' and 'ep2' to remove operands common to both. |
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* Example reductions: |
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* |
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* ep1: A && B -> ep1: y |
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* ep2: A && B && C -> ep2: C |
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* |
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* ep1: A || B -> ep1: n |
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* ep2: A || B || C -> ep2: C |
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* |
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* ep1: A && (B && FOO) -> ep1: FOO |
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* ep2: (BAR && B) && A -> ep2: BAR |
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* |
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* ep1: A && (B || C) -> ep1: y |
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* ep2: (C || B) && A -> ep2: y |
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* |
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* Comparisons are done between all operands at the same "level" of && or ||. |
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* For example, in the expression 'e1 && (e2 || e3) && (e4 || e5)', the |
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* following operands will be compared: |
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* |
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* - 'e1', 'e2 || e3', and 'e4 || e5', against each other |
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* - e2 against e3 |
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* - e4 against e5 |
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* |
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* Parentheses are irrelevant within a single level. 'e1 && (e2 && e3)' and |
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* '(e1 && e2) && e3' are both a single level. |
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* |
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* See __expr_eliminate_eq() as well. |
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*/ |
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void expr_eliminate_eq(struct expr **ep1, struct expr **ep2) |
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{ |
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if (!e1 || !e2) |
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return; |
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switch (e1->type) { |
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case E_OR: |
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case E_AND: |
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__expr_eliminate_eq(e1->type, ep1, ep2); |
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default: |
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; |
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} |
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if (e1->type != e2->type) switch (e2->type) { |
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case E_OR: |
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case E_AND: |
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__expr_eliminate_eq(e2->type, ep1, ep2); |
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default: |
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; |
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} |
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e1 = expr_eliminate_yn(e1); |
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e2 = expr_eliminate_yn(e2); |
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} |
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#undef e1 |
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#undef e2 |
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/* |
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* Returns true if 'e1' and 'e2' are equal, after minor simplification. Two |
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* &&/|| expressions are considered equal if every operand in one expression |
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* equals some operand in the other (operands do not need to appear in the same |
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* order), recursively. |
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*/ |
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int expr_eq(struct expr *e1, struct expr *e2) |
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{ |
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int res, old_count; |
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/* |
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* A NULL expr is taken to be yes, but there's also a different way to |
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* represent yes. expr_is_yes() checks for either representation. |
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*/ |
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if (!e1 || !e2) |
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return expr_is_yes(e1) && expr_is_yes(e2); |
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if (e1->type != e2->type) |
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return 0; |
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switch (e1->type) { |
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case E_EQUAL: |
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case E_GEQ: |
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case E_GTH: |
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case E_LEQ: |
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case E_LTH: |
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case E_UNEQUAL: |
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return e1->left.sym == e2->left.sym && e1->right.sym == e2->right.sym; |
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case E_SYMBOL: |
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return e1->left.sym == e2->left.sym; |
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case E_NOT: |
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return expr_eq(e1->left.expr, e2->left.expr); |
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case E_AND: |
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case E_OR: |
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e1 = expr_copy(e1); |
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e2 = expr_copy(e2); |
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old_count = trans_count; |
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expr_eliminate_eq(&e1, &e2); |
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res = (e1->type == E_SYMBOL && e2->type == E_SYMBOL && |
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e1->left.sym == e2->left.sym); |
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expr_free(e1); |
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expr_free(e2); |
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trans_count = old_count; |
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return res; |
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case E_LIST: |
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case E_RANGE: |
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case E_NONE: |
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/* panic */; |
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} |
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if (DEBUG_EXPR) { |
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expr_fprint(e1, stdout); |
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printf(" = "); |
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expr_fprint(e2, stdout); |
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printf(" ?\n"); |
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} |
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return 0; |
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} |
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/* |
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* Recursively performs the following simplifications in-place (as well as the |
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* corresponding simplifications with swapped operands): |
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* |
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* expr && n -> n |
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* expr && y -> expr |
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* expr || n -> expr |
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* expr || y -> y |
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* |
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* Returns the optimized expression. |
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*/ |
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static struct expr *expr_eliminate_yn(struct expr *e) |
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{ |
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struct expr *tmp; |
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if (e) switch (e->type) { |
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case E_AND: |
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e->left.expr = expr_eliminate_yn(e->left.expr); |
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e->right.expr = expr_eliminate_yn(e->right.expr); |
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if (e->left.expr->type == E_SYMBOL) { |
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if (e->left.expr->left.sym == &symbol_no) { |
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expr_free(e->left.expr); |
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expr_free(e->right.expr); |
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e->type = E_SYMBOL; |
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e->left.sym = &symbol_no; |
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e->right.expr = NULL; |
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return e; |
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} else if (e->left.expr->left.sym == &symbol_yes) { |
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free(e->left.expr); |
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tmp = e->right.expr; |
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*e = *(e->right.expr); |
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free(tmp); |
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return e; |
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} |
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} |
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if (e->right.expr->type == E_SYMBOL) { |
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if (e->right.expr->left.sym == &symbol_no) { |
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expr_free(e->left.expr); |
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expr_free(e->right.expr); |
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e->type = E_SYMBOL; |
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e->left.sym = &symbol_no; |
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e->right.expr = NULL; |
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return e; |
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} else if (e->right.expr->left.sym == &symbol_yes) { |
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free(e->right.expr); |
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tmp = e->left.expr; |
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*e = *(e->left.expr); |
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free(tmp); |
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return e; |
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} |
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} |
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break; |
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case E_OR: |
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e->left.expr = expr_eliminate_yn(e->left.expr); |
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e->right.expr = expr_eliminate_yn(e->right.expr); |
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if (e->left.expr->type == E_SYMBOL) { |
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if (e->left.expr->left.sym == &symbol_no) { |
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free(e->left.expr); |
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tmp = e->right.expr; |
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*e = *(e->right.expr); |
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free(tmp); |
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return e; |
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} else if (e->left.expr->left.sym == &symbol_yes) { |
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expr_free(e->left.expr); |
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expr_free(e->right.expr); |
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e->type = E_SYMBOL; |
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e->left.sym = &symbol_yes; |
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e->right.expr = NULL; |
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return e; |
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} |
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} |
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if (e->right.expr->type == E_SYMBOL) { |
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if (e->right.expr->left.sym == &symbol_no) { |
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free(e->right.expr); |
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tmp = e->left.expr; |
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*e = *(e->left.expr); |
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free(tmp); |
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return e; |
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} else if (e->right.expr->left.sym == &symbol_yes) { |
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expr_free(e->left.expr); |
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expr_free(e->right.expr); |
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e->type = E_SYMBOL; |
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e->left.sym = &symbol_yes; |
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e->right.expr = NULL; |
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return e; |
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} |
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} |
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break; |
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default: |
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; |
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} |
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return e; |
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} |
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/* |
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* bool FOO!=n => FOO |
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*/ |
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struct expr *expr_trans_bool(struct expr *e) |
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{ |
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if (!e) |
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return NULL; |
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switch (e->type) { |
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case E_AND: |
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case E_OR: |
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case E_NOT: |
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e->left.expr = expr_trans_bool(e->left.expr); |
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e->right.expr = expr_trans_bool(e->right.expr); |
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break; |
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case E_UNEQUAL: |
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// FOO!=n -> FOO |
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if (e->left.sym->type == S_TRISTATE) { |
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if (e->right.sym == &symbol_no) { |
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e->type = E_SYMBOL; |
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e->right.sym = NULL; |
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} |
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} |
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break; |
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default: |
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; |
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} |
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return e; |
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} |
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/* |
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* e1 || e2 -> ? |
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*/ |
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static struct expr *expr_join_or(struct expr *e1, struct expr *e2) |
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{ |
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struct expr *tmp; |
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struct symbol *sym1, *sym2; |
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if (expr_eq(e1, e2)) |
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return expr_copy(e1); |
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if (e1->type != E_EQUAL && e1->type != E_UNEQUAL && e1->type != E_SYMBOL && e1->type != E_NOT) |
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return NULL; |
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if (e2->type != E_EQUAL && e2->type != E_UNEQUAL && e2->type != E_SYMBOL && e2->type != E_NOT) |
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return NULL; |
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if (e1->type == E_NOT) { |
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tmp = e1->left.expr; |
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if (tmp->type != E_EQUAL && tmp->type != E_UNEQUAL && tmp->type != E_SYMBOL) |
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return NULL; |
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sym1 = tmp->left.sym; |
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} else |
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sym1 = e1->left.sym; |
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if (e2->type == E_NOT) { |
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if (e2->left.expr->type != E_SYMBOL) |
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return NULL; |
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sym2 = e2->left.expr->left.sym; |
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} else |
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sym2 = e2->left.sym; |
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if (sym1 != sym2) |
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return NULL; |
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if (sym1->type != S_BOOLEAN && sym1->type != S_TRISTATE) |
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return NULL; |
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if (sym1->type == S_TRISTATE) { |
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if (e1->type == E_EQUAL && e2->type == E_EQUAL && |
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((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_mod) || |
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(e1->right.sym == &symbol_mod && e2->right.sym == &symbol_yes))) { |
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// (a='y') || (a='m') -> (a!='n') |
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return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_no); |
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} |
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if (e1->type == E_EQUAL && e2->type == E_EQUAL && |
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((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_no) || |
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(e1->right.sym == &symbol_no && e2->right.sym == &symbol_yes))) { |
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// (a='y') || (a='n') -> (a!='m') |
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return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_mod); |
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} |
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if (e1->type == E_EQUAL && e2->type == E_EQUAL && |
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((e1->right.sym == &symbol_mod && e2->right.sym == &symbol_no) || |
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(e1->right.sym == &symbol_no && e2->right.sym == &symbol_mod))) { |
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// (a='m') || (a='n') -> (a!='y') |
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return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_yes); |
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} |
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} |
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if (sym1->type == S_BOOLEAN && sym1 == sym2) { |
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if ((e1->type == E_NOT && e1->left.expr->type == E_SYMBOL && e2->type == E_SYMBOL) || |
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(e2->type == E_NOT && e2->left.expr->type == E_SYMBOL && e1->type == E_SYMBOL)) |
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return expr_alloc_symbol(&symbol_yes); |
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} |
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|
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if (DEBUG_EXPR) { |
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printf("optimize ("); |
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expr_fprint(e1, stdout); |
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printf(") || ("); |
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expr_fprint(e2, stdout); |
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printf(")?\n"); |
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} |
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return NULL; |
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} |
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|
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static struct expr *expr_join_and(struct expr *e1, struct expr *e2) |
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{ |
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struct expr *tmp; |
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struct symbol *sym1, *sym2; |
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|
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if (expr_eq(e1, e2)) |
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return expr_copy(e1); |
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if (e1->type != E_EQUAL && e1->type != E_UNEQUAL && e1->type != E_SYMBOL && e1->type != E_NOT) |
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return NULL; |
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if (e2->type != E_EQUAL && e2->type != E_UNEQUAL && e2->type != E_SYMBOL && e2->type != E_NOT) |
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return NULL; |
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if (e1->type == E_NOT) { |
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tmp = e1->left.expr; |
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if (tmp->type != E_EQUAL && tmp->type != E_UNEQUAL && tmp->type != E_SYMBOL) |
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return NULL; |
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sym1 = tmp->left.sym; |
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} else |
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sym1 = e1->left.sym; |
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if (e2->type == E_NOT) { |
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if (e2->left.expr->type != E_SYMBOL) |
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return NULL; |
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sym2 = e2->left.expr->left.sym; |
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} else |
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sym2 = e2->left.sym; |
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if (sym1 != sym2) |
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return NULL; |
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if (sym1->type != S_BOOLEAN && sym1->type != S_TRISTATE) |
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return NULL; |
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|
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if ((e1->type == E_SYMBOL && e2->type == E_EQUAL && e2->right.sym == &symbol_yes) || |
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(e2->type == E_SYMBOL && e1->type == E_EQUAL && e1->right.sym == &symbol_yes)) |
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// (a) && (a='y') -> (a='y') |
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return expr_alloc_comp(E_EQUAL, sym1, &symbol_yes); |
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|
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if ((e1->type == E_SYMBOL && e2->type == E_UNEQUAL && e2->right.sym == &symbol_no) || |
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(e2->type == E_SYMBOL && e1->type == E_UNEQUAL && e1->right.sym == &symbol_no)) |
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// (a) && (a!='n') -> (a) |
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return expr_alloc_symbol(sym1); |
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|
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if ((e1->type == E_SYMBOL && e2->type == E_UNEQUAL && e2->right.sym == &symbol_mod) || |
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(e2->type == E_SYMBOL && e1->type == E_UNEQUAL && e1->right.sym == &symbol_mod)) |
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// (a) && (a!='m') -> (a='y') |
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return expr_alloc_comp(E_EQUAL, sym1, &symbol_yes); |
|
|
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if (sym1->type == S_TRISTATE) { |
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if (e1->type == E_EQUAL && e2->type == E_UNEQUAL) { |
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// (a='b') && (a!='c') -> 'b'='c' ? 'n' : a='b' |
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sym2 = e1->right.sym; |
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if ((e2->right.sym->flags & SYMBOL_CONST) && (sym2->flags & SYMBOL_CONST)) |
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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' |
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sym2 = e2->right.sym; |
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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); |
|
}
|
|
|