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| author | Nicolai Stange <nicstange@gmail.com> | 2016-02-01 03:33:38 +0100 |
|---|---|---|
| committer | Luc Van Oostenryck <luc.vanoostenryck@gmail.com> | 2017-03-31 02:14:10 +0200 |
| commit | ccd9e3b5c6ab48bc03b52014a48ea53d681aa704 (patch) | |
| tree | 9a6f998f985333900315c5c2bbee099269b0bc61 | |
| parent | 4a99724da62bfe56c6347be07cf01579b16c6e68 (diff) | |
| download | sparse-dev-ccd9e3b5c6ab48bc03b52014a48ea53d681aa704.tar.gz | |
constexpr: examine constness of preops at evaluation only
Move the whole calculation of prefix expressions' constness flags to
the evaluation phase such that expressions like
-__builtin_choose_expr(0, 0, 0)
~__builtin_choose_expr(0, 0, 0)
!__builtin_choose_expr(0, 0, 0)
can now be recognized as qualifying as integer constant expressions.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
| -rw-r--r-- | evaluate.c | 8 | ||||
| -rw-r--r-- | expression.c | 3 | ||||
| -rw-r--r-- | validation/constexpr-preop.c | 29 |
3 files changed, 33 insertions, 7 deletions
@@ -1805,8 +1805,8 @@ static struct symbol *evaluate_sign(struct expression *expr) { struct symbol *ctype = expr->unop->ctype; int class = classify_type(ctype, &ctype); - if (expr->flags && !(expr->unop->flags & CEF_ICE)) - expr->flags = CEF_NONE; + unsigned char flags = expr->unop->flags & ~CEF_CONST_MASK; + /* should be an arithmetic type */ if (!(class & TYPE_NUM)) return bad_expr_type(expr); @@ -1823,6 +1823,7 @@ Normal: } if (expr->op == '+') *expr = *expr->unop; + expr->flags = flags; expr->ctype = ctype; return ctype; Restr: @@ -1860,8 +1861,7 @@ static struct symbol *evaluate_preop(struct expression *expr) return evaluate_postop(expr); case '!': - if (expr->flags && !(expr->unop->flags & CEF_ICE)) - expr->flags = CEF_NONE; + expr->flags = expr->unop->flags & ~CEF_CONST_MASK; if (is_safe_type(ctype)) warning(expr->pos, "testing a 'safe expression'"); if (is_float_type(ctype)) { diff --git a/expression.c b/expression.c index b59af888..0332c440 100644 --- a/expression.c +++ b/expression.c @@ -450,8 +450,6 @@ struct token *primary_expression(struct token *token, struct expression **tree) expr = alloc_expression(token->pos, EXPR_PREOP); expr->op = '('; token = parens_expression(token, &expr->unop, "in expression"); - if (expr->unop) - expr->flags = expr->unop->flags; break; } if (token->special == '[' && lookup_type(token->next)) { @@ -663,7 +661,6 @@ static struct token *unary_expression(struct token *token, struct expression **t unary = alloc_expression(token->pos, EXPR_PREOP); unary->op = token->special; unary->unop = unop; - unary->flags = unop->flags & ~CEF_CONST_MASK; *tree = unary; return next; } diff --git a/validation/constexpr-preop.c b/validation/constexpr-preop.c new file mode 100644 index 00000000..5d869da4 --- /dev/null +++ b/validation/constexpr-preop.c @@ -0,0 +1,29 @@ +static int a[] = { + [+0] = 0, // OK + [+__builtin_choose_expr(0, 0, 0)] = 0, // OK + [+0.] = 0, // KO + [+__builtin_choose_expr(0, 0, 0.)] = 0, // KO + [-0] = 0, // OK + [-__builtin_choose_expr(0, 0, 0)] = 0, // OK + [-0.] = 0, // KO + [-__builtin_choose_expr(0, 0, 0.)] = 0, // KO + [~0] = 0, // OK + [~__builtin_choose_expr(0, 0, 0)] = 0, // OK + [!0] = 0, // OK + [!__builtin_choose_expr(0, 0, 0)] = 0, // OK + [!0.] = 0, // KO + [!__builtin_choose_expr(0, 0, 0.)] = 0, // KO +}; + +/* + * check-name: Expression constness propagation in preops + * + * check-error-start +constexpr-preop.c:4:5: error: bad constant expression +constexpr-preop.c:5:33: error: bad constant expression +constexpr-preop.c:8:4: error: bad constant expression +constexpr-preop.c:9:4: error: bad constant expression +constexpr-preop.c:14:4: error: bad integer constant expression +constexpr-preop.c:15:4: error: bad integer constant expression + * check-error-end + */ |