diff options
| -rw-r--r-- | gcc/c/c-parser.cc | 71 | ||||
| -rw-r--r-- | gcc/c/c-tree.h | 2 | ||||
| -rw-r--r-- | gcc/c/c-typeck.cc | 7 |
3 files changed, 64 insertions, 16 deletions
diff --git a/gcc/c/c-parser.cc b/gcc/c/c-parser.cc index 12c5ed5..9b9284b 100644 --- a/gcc/c/c-parser.cc +++ b/gcc/c/c-parser.cc @@ -1621,6 +1621,12 @@ struct omp_for_parse_data { bool fail : 1; }; +struct attr_state +{ + /* True if we parsed a musttail attribute for return. */ + bool musttail_p; +}; + static bool c_parser_nth_token_starts_std_attributes (c_parser *, unsigned int); static tree c_parser_std_attribute_specifier_sequence (c_parser *); @@ -1665,7 +1671,8 @@ static location_t c_parser_compound_statement_nostart (c_parser *); static void c_parser_label (c_parser *, tree); static void c_parser_statement (c_parser *, bool *, location_t * = NULL); static void c_parser_statement_after_labels (c_parser *, bool *, - vec<tree> * = NULL); + vec<tree> * = NULL, + attr_state = {}); static tree c_parser_c99_block_statement (c_parser *, bool *, location_t * = NULL); static void c_parser_if_statement (c_parser *, bool *, vec<tree> *); @@ -6982,6 +6989,29 @@ c_parser_handle_directive_omp_attributes (tree &attrs, } } +/* Check if STD_ATTR contains a musttail attribute and remove if it + precedes a return. PARSER is the parser and ATTR is the output + attr_state. */ + +static tree +c_parser_handle_musttail (c_parser *parser, tree std_attrs, attr_state &attr) +{ + if (c_parser_next_token_is_keyword (parser, RID_RETURN)) + { + if (lookup_attribute ("gnu", "musttail", std_attrs)) + { + std_attrs = remove_attribute ("gnu", "musttail", std_attrs); + attr.musttail_p = true; + } + if (lookup_attribute ("clang", "musttail", std_attrs)) + { + std_attrs = remove_attribute ("clang", "musttail", std_attrs); + attr.musttail_p = true; + } + } + return std_attrs; +} + /* Parse a compound statement except for the opening brace. This is used for parsing both compound statements and statement expressions (which follow different paths to handling the opening). */ @@ -6998,6 +7028,7 @@ c_parser_compound_statement_nostart (c_parser *parser) bool in_omp_loop_block = omp_for_parse_state ? omp_for_parse_state->want_nested_loop : false; tree sl = NULL_TREE; + attr_state a = {}; if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE)) { @@ -7138,7 +7169,10 @@ c_parser_compound_statement_nostart (c_parser *parser) = c_parser_nth_token_starts_std_attributes (parser, 1); tree std_attrs = NULL_TREE; if (have_std_attrs) - std_attrs = c_parser_std_attribute_specifier_sequence (parser); + { + std_attrs = c_parser_std_attribute_specifier_sequence (parser); + std_attrs = c_parser_handle_musttail (parser, std_attrs, a); + } if (c_parser_next_token_is_keyword (parser, RID_CASE) || c_parser_next_token_is_keyword (parser, RID_DEFAULT) || (c_parser_next_token_is (parser, CPP_NAME) @@ -7286,7 +7320,7 @@ c_parser_compound_statement_nostart (c_parser *parser) last_stmt = true; mark_valid_location_for_stdc_pragma (false); if (!omp_for_parse_state) - c_parser_statement_after_labels (parser, NULL); + c_parser_statement_after_labels (parser, NULL, NULL, a); else { /* In canonical loop nest form, nested loops can only appear @@ -7328,15 +7362,20 @@ c_parser_compound_statement_nostart (c_parser *parser) /* Parse all consecutive labels, possibly preceded by standard attributes. In this context, a statement is required, not a declaration, so attributes must be followed by a statement that is - not just a semicolon. */ + not just a semicolon. Returns an attr_state. */ -static void +static attr_state c_parser_all_labels (c_parser *parser) { + attr_state attr = {}; bool have_std_attrs; tree std_attrs = NULL; if ((have_std_attrs = c_parser_nth_token_starts_std_attributes (parser, 1))) - std_attrs = c_parser_std_attribute_specifier_sequence (parser); + { + std_attrs = c_parser_std_attribute_specifier_sequence (parser); + std_attrs = c_parser_handle_musttail (parser, std_attrs, attr); + } + while (c_parser_next_token_is_keyword (parser, RID_CASE) || c_parser_next_token_is_keyword (parser, RID_DEFAULT) || (c_parser_next_token_is (parser, CPP_NAME) @@ -7346,7 +7385,10 @@ c_parser_all_labels (c_parser *parser) std_attrs = NULL; if ((have_std_attrs = c_parser_nth_token_starts_std_attributes (parser, 1))) - std_attrs = c_parser_std_attribute_specifier_sequence (parser); + { + std_attrs = c_parser_std_attribute_specifier_sequence (parser); + std_attrs = c_parser_handle_musttail (parser, std_attrs, attr); + } } if (std_attrs && (!c_parser_handle_statement_omp_attributes (parser, std_attrs, &have_std_attrs) @@ -7358,6 +7400,7 @@ c_parser_all_labels (c_parser *parser) } else if (have_std_attrs && c_parser_next_token_is (parser, CPP_SEMICOLON)) c_parser_error (parser, "expected statement"); + return attr; } /* Parse a label (C90 6.6.1, C99 6.8.1, C11 6.8.1). @@ -7601,11 +7644,11 @@ c_parser_label (c_parser *parser, tree std_attrs) static void c_parser_statement (c_parser *parser, bool *if_p, location_t *loc_after_labels) { - c_parser_all_labels (parser); + attr_state a = c_parser_all_labels (parser); if (loc_after_labels) *loc_after_labels = c_parser_peek_token (parser)->location; parser->omp_attrs_forbidden_p = false; - c_parser_statement_after_labels (parser, if_p, NULL); + c_parser_statement_after_labels (parser, if_p, NULL, a); } /* Parse a statement, other than a labeled statement. CHAIN is a vector @@ -7614,11 +7657,11 @@ c_parser_statement (c_parser *parser, bool *if_p, location_t *loc_after_labels) IF_P is used to track whether there's a (possibly labeled) if statement which is not enclosed in braces and has an else clause. This is used to - implement -Wparentheses. */ + implement -Wparentheses. ASTATE is an earlier parsed attribute state. */ static void c_parser_statement_after_labels (c_parser *parser, bool *if_p, - vec<tree> *chain) + vec<tree> *chain, attr_state astate) { location_t loc = c_parser_peek_token (parser)->location; tree stmt = NULL_TREE; @@ -7686,7 +7729,8 @@ c_parser_statement_after_labels (c_parser *parser, bool *if_p, c_parser_consume_token (parser); if (c_parser_next_token_is (parser, CPP_SEMICOLON)) { - stmt = c_finish_return (loc, NULL_TREE, NULL_TREE); + stmt = c_finish_return (loc, NULL_TREE, NULL_TREE, + astate.musttail_p); c_parser_consume_token (parser); } else @@ -7695,7 +7739,8 @@ c_parser_statement_after_labels (c_parser *parser, bool *if_p, struct c_expr expr = c_parser_expression_conv (parser); mark_exp_read (expr.value); stmt = c_finish_return (EXPR_LOC_OR_LOC (expr.value, xloc), - expr.value, expr.original_type); + expr.value, expr.original_type, + astate.musttail_p); goto expect_semicolon; } break; diff --git a/gcc/c/c-tree.h b/gcc/c/c-tree.h index 15da875..3dc6338 100644 --- a/gcc/c/c-tree.h +++ b/gcc/c/c-tree.h @@ -827,7 +827,7 @@ extern tree c_begin_stmt_expr (void); extern tree c_finish_stmt_expr (location_t, tree); extern tree c_process_expr_stmt (location_t, tree); extern tree c_finish_expr_stmt (location_t, tree); -extern tree c_finish_return (location_t, tree, tree); +extern tree c_finish_return (location_t, tree, tree, bool = false); extern tree c_finish_bc_stmt (location_t, tree, bool); extern tree c_finish_goto_label (location_t, tree); extern tree c_finish_goto_ptr (location_t, c_expr val); diff --git a/gcc/c/c-typeck.cc b/gcc/c/c-typeck.cc index 7e0f01e..094e41f 100644 --- a/gcc/c/c-typeck.cc +++ b/gcc/c/c-typeck.cc @@ -11725,10 +11725,11 @@ c_finish_goto_ptr (location_t loc, c_expr val) to return, or a null pointer for `return;' with no value. LOC is the location of the return statement, or the location of the expression, if the statement has any. If ORIGTYPE is not NULL_TREE, it - is the original type of RETVAL. */ + is the original type of RETVAL. MUSTTAIL_P indicates a musttail + attribute. */ tree -c_finish_return (location_t loc, tree retval, tree origtype) +c_finish_return (location_t loc, tree retval, tree origtype, bool musttail_p) { tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt; bool no_warning = false; @@ -11742,6 +11743,8 @@ c_finish_return (location_t loc, tree retval, tree origtype) warning_at (xloc, 0, "function declared %<noreturn%> has a %<return%> statement"); + set_musttail_on_return (retval, xloc, musttail_p); + if (retval) { tree semantic_type = NULL_TREE; |