linux-stable/scripts/kconfig/expr.c
Thomas Hebb 3460d0bc25 kconfig: distinguish between dependencies and visibility in help text
Kconfig makes a distinction between dependencies (defined by "depends
on" expressions and enclosing "if" blocks) and visibility (which
includes all dependencies, but also includes inline "if" expressions of
individual properties as well as, for prompts, "visible if" expressions
of enclosing menus).

Before commit bcdedcc1af ("menuconfig: print more info for symbol
without prompts"), the "Depends on" lines of a symbol's help text
indicated the visibility of the prompt property they appeared under.
After bcdedcc1af, there was always only a single "Depends on" line,
which indicated the visibility of the first P_SYMBOL property of the
symbol. Since P_SYMBOLs never have inline if expressions, this was in
effect the same as the dependencies of the menu item that the P_SYMBOL
was attached to.

Neither of these situations accurately conveyed the dependencies of a
symbol--the first because it was actually the visibility, and the second
because it only showed the dependencies from a single definition.

With this series, we are back to printing separate dependencies for each
definition, but we print the actual dependencies (rather than the
visibility) in the "Depends on" line. However, it can still be useful to
know the visibility of a prompt, so this patch adds a "Visible if" line
that shows the visibility only if the visibility is different from the
dependencies (which it isn't for most prompts in Linux).

Before:

  Symbol: THUMB2_KERNEL [=n]
  Type  : bool
  Defined at arch/arm/Kconfig:1417
    Prompt: Compile the kernel in Thumb-2 mode
    Depends on: (CPU_V7 [=y] || CPU_V7M [=n]) && !CPU_V6 [=n] && !CPU_V6K [=n]
    Location:
      -> Kernel Features
    Selects: ARM_UNWIND [=n]

After:

   Symbol: THUMB2_KERNEL [=n]
   Type  : bool
   Defined at arch/arm/Kconfig:1417
     Prompt: Compile the kernel in Thumb-2 mode
     Depends on: (CPU_V7 [=y] || CPU_V7M [=n]) && !CPU_V6 [=n] && !CPU_V6K [=n]
     Visible if: (CPU_V7 [=y] || CPU_V7M [=n]) && !CPU_V6 [=n] && !CPU_V6K [=n] && !CPU_THUMBONLY [=n]
     Location:
       -> Kernel Features
     Selects: ARM_UNWIND [=n]

Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-01-07 02:18:45 +09:00

1303 lines
30 KiB
C

// 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);
}