decl2.c (generate_ctor_or_dtor_function): Avoid expanding a global static constructor/destructor if it will be empty, i.e.

* decl2.c (generate_ctor_or_dtor_function): Avoid expanding a
	global static constructor/destructor if it will be empty, i.e.
	either doesn't call any ctors/dtors or only calls pure or const
	ctors/dtors.

From-SVN: r67800
This commit is contained in:
Roger Sayle 2003-06-11 22:29:41 +00:00 committed by Roger Sayle
parent 7fb26bb001
commit 35b4a5768f
2 changed files with 39 additions and 14 deletions

View File

@ -1,3 +1,10 @@
2003-06-11 Roger Sayle <roger@eyesopen.com>
* decl2.c (generate_ctor_or_dtor_function): Avoid expanding a
global static constructor/destructor if it will be empty, i.e.
either doesn't call any ctors/dtors or only calls pure or const
ctors/dtors.
2003-06-11 Mark Mitchell <mark@codesourcery.com>
* mangle.c (tm_p.h): Include it.

View File

@ -2467,6 +2467,7 @@ generate_ctor_or_dtor_function (bool constructor_p, int priority,
{
char function_key;
tree arguments;
tree fndecl;
tree body;
size_t i;
@ -2475,25 +2476,31 @@ generate_ctor_or_dtor_function (bool constructor_p, int priority,
/* We use `I' to indicate initialization and `D' to indicate
destruction. */
if (constructor_p)
function_key = 'I';
else
function_key = 'D';
function_key = constructor_p ? 'I' : 'D';
/* Begin the function. */
body = start_objects (function_key, priority);
/* We emit the function lazily, to avoid generating empty
global constructors and destructors. */
body = NULL_TREE;
/* Call the static storage duration function with appropriate
arguments. */
if (ssdf_decls)
for (i = 0; i < ssdf_decls->elements_used; ++i)
{
arguments = tree_cons (NULL_TREE, build_int_2 (priority, 0),
NULL_TREE);
arguments = tree_cons (NULL_TREE, build_int_2 (constructor_p, 0),
arguments);
finish_expr_stmt (build_function_call (VARRAY_TREE (ssdf_decls, i),
arguments));
fndecl = VARRAY_TREE (ssdf_decls, i);
/* Calls to pure or const functions will expand to nothing. */
if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE)))
{
if (! body)
body = start_objects (function_key, priority);
arguments = tree_cons (NULL_TREE, build_int_2 (priority, 0),
NULL_TREE);
arguments = tree_cons (NULL_TREE, build_int_2 (constructor_p, 0),
arguments);
finish_expr_stmt (build_function_call (fndecl, arguments));
}
}
/* If we're generating code for the DEFAULT_INIT_PRIORITY, throw in
@ -2506,11 +2513,22 @@ generate_ctor_or_dtor_function (bool constructor_p, int priority,
for (fns = constructor_p ? static_ctors : static_dtors;
fns;
fns = TREE_CHAIN (fns))
finish_expr_stmt (build_function_call (TREE_VALUE (fns), NULL_TREE));
{
fndecl = TREE_VALUE (fns);
/* Calls to pure/const functions will expand to nothing. */
if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE)))
{
if (! body)
body = start_objects (function_key, priority);
finish_expr_stmt (build_function_call (fndecl, NULL_TREE));
}
}
}
/* Close out the function. */
finish_objects (function_key, priority, body);
if (body)
finish_objects (function_key, priority, body);
}
/* Generate constructor and destructor functions for the priority