diff options
Diffstat (limited to 'scripts/kconfig/expr.c')
| -rw-r--r-- | scripts/kconfig/expr.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c index 16f92c4a775a..2b91d16bf14f 100644 --- a/scripts/kconfig/expr.c +++ b/scripts/kconfig/expr.c @@ -738,6 +738,39 @@ bool expr_contains_symbol(struct expr *dep, struct symbol *sym) return false; } +/* + * Check if the expression references 'sym' in a way that is satisfiable + * with 'sym' disabled, e.g.'sym!=y'. + * + * Expects that expr_transform() was already called on 'expr'. + */ +bool expr_contains_symbol_negated(struct expr *dep, struct symbol *sym) +{ + if (!dep) + return false; + + switch (dep->type) { + case E_AND: + case E_OR: + return expr_contains_symbol_negated(dep->left.expr, sym) || + expr_contains_symbol_negated(dep->right.expr, sym); + case E_NOT: + return dep->left.expr->type == E_SYMBOL && + dep->left.expr->left.sym == sym; + case E_EQUAL: + /* sym=n */ + return dep->left.sym == sym && dep->right.sym == &symbol_no; + case E_UNEQUAL: + /* sym!=y, sym!=m */ + return dep->left.sym == sym && + (dep->right.sym == &symbol_yes || + dep->right.sym == &symbol_mod); + default: + break; + } + return false; +} + bool expr_depends_symbol(struct expr *dep, struct symbol *sym) { if (!dep) |