diff options
Diffstat (limited to 'gcc/ada/gcc-interface/decl.c')
| -rw-r--r-- | gcc/ada/gcc-interface/decl.c | 77 |
1 files changed, 47 insertions, 30 deletions
diff --git a/gcc/ada/gcc-interface/decl.c b/gcc/ada/gcc-interface/decl.c index a10fc2d..696e49a 100644 --- a/gcc/ada/gcc-interface/decl.c +++ b/gcc/ada/gcc-interface/decl.c @@ -6003,15 +6003,9 @@ static tree elaborate_expression_1 (tree gnu_expr, Entity_Id gnat_entity, tree gnu_name, bool definition, bool need_debug) { - /* Skip any conversions and simple arithmetics to see if the expression - is a read-only variable. - ??? This really should remain read-only, but we have to think about - the typing of the tree here. */ - tree gnu_inner_expr - = skip_simple_arithmetic (remove_conversions (gnu_expr, true)); - tree gnu_decl = NULL_TREE; - bool expr_global = Is_Public (gnat_entity) || global_bindings_p (); - bool expr_variable; + const bool expr_global_p = Is_Public (gnat_entity) || global_bindings_p (); + bool expr_variable_p; + tree gnu_decl; /* In most cases, we won't see a naked FIELD_DECL because a discriminant reference will have been replaced with a COMPONENT_REF when the type @@ -6023,39 +6017,62 @@ elaborate_expression_1 (tree gnu_expr, Entity_Id gnat_entity, tree gnu_name, build0 (PLACEHOLDER_EXPR, DECL_CONTEXT (gnu_expr)), gnu_expr, NULL_TREE); - /* If GNU_EXPR is neither a placeholder nor a constant, nor a variable - that is read-only, make a variable that is initialized to contain the - bound when the package containing the definition is elaborated. If - this entity is defined at top level and a bound or discriminant value - isn't a constant or a reference to a discriminant, replace the bound - by the variable; otherwise use a SAVE_EXPR if needed. Note that we - rely here on the fact that an expression cannot contain both the - discriminant and some other variable. */ - expr_variable = (!CONSTANT_CLASS_P (gnu_expr) - && !(TREE_CODE (gnu_inner_expr) == VAR_DECL - && (TREE_READONLY (gnu_inner_expr) - || DECL_READONLY_ONCE_ELAB (gnu_inner_expr))) - && !CONTAINS_PLACEHOLDER_P (gnu_expr)); - - /* If GNU_EXPR contains a discriminant, we can't elaborate a variable. */ - if (need_debug && CONTAINS_PLACEHOLDER_P (gnu_expr)) - need_debug = false; + /* If GNU_EXPR contains a placeholder, just return it. We rely on the fact + that an expression cannot contain both a discriminant and a variable. */ + if (CONTAINS_PLACEHOLDER_P (gnu_expr)) + return gnu_expr; + + /* If GNU_EXPR is neither a constant nor based on a read-only variable, make + a variable that is initialized to contain the expression when the package + containing the definition is elaborated. If this entity is defined at top + level, replace the expression by the variable; otherwise use a SAVE_EXPR + if this is necessary. */ + if (CONSTANT_CLASS_P (gnu_expr)) + expr_variable_p = false; + else + { + /* Skip any conversions and simple arithmetics to see if the expression + is based on a read-only variable. + ??? This really should remain read-only, but we have to think about + the typing of the tree here. */ + tree inner + = skip_simple_arithmetic (remove_conversions (gnu_expr, true)); + + if (handled_component_p (inner)) + { + HOST_WIDE_INT bitsize, bitpos; + tree offset; + enum machine_mode mode; + int unsignedp, volatilep; + + inner = get_inner_reference (inner, &bitsize, &bitpos, &offset, + &mode, &unsignedp, &volatilep, false); + /* If the offset is variable, err on the side of caution. */ + if (offset) + inner = NULL_TREE; + } + + expr_variable_p + = !(inner + && TREE_CODE (inner) == VAR_DECL + && (TREE_READONLY (inner) || DECL_READONLY_ONCE_ELAB (inner))); + } /* Now create the variable if we need it. */ - if (need_debug || (expr_variable && expr_global)) + if (need_debug || (expr_variable_p && expr_global_p)) gnu_decl = create_var_decl (create_concat_name (gnat_entity, IDENTIFIER_POINTER (gnu_name)), NULL_TREE, TREE_TYPE (gnu_expr), gnu_expr, !need_debug, Is_Public (gnat_entity), - !definition, expr_global, NULL, gnat_entity); + !definition, expr_global_p, NULL, gnat_entity); /* We only need to use this variable if we are in global context since GCC can do the right thing in the local case. */ - if (expr_global && expr_variable) + if (expr_global_p && expr_variable_p) return gnu_decl; - return expr_variable ? gnat_save_expr (gnu_expr) : gnu_expr; + return expr_variable_p ? gnat_save_expr (gnu_expr) : gnu_expr; } /* Similar, but take an alignment factor and make it explicit in the tree. */ |