[Ada] Robustify renaming code in gigi

[Eric Botcazou]

This makes the renaming code in gigi more robust in preparation for further 
changes related to renaming.

Tested on x86_64-suse-linux, applied on the mainline.


2014-04-15  Eric Botcazou  <ebotcazou@adacore.com>
            Pierre-Marie de Rodat  <derodat@adacore.com>

	* gcc-interface/decl.c (gnat_to_gnu_entity) <object>: Create a mere
	scalar constant instead of a reference for renaming of scalar literal.
	Do not create a new object for constant renaming except for a function
	call.  Make sure a VAR_DECL is created for the renaming pointer.
	* gcc-interface/trans.c (constant_decl_with_initializer_p): New.
	(fold_constant_decl_in_expr): New function.
	(Identifier_to_gnu): Use constant_decl_with_initializer_p.
	For a constant renaming, try to fold a constant DECL in the result.
	(lvalue_required_p) <N_Object_Renaming_Declaration>: Always return 1.
	(Identifier_to_gnu): Reference the renamed object of constant renaming
	pointers directly.
	(Case_Statement_to_gnu): Do not re-fold the bounds of integer types.
	Assert that the case values are constant.
	* gcc-interface/utils.c (invalidate_global_renaming_pointers): Do not
	invalidate constant renaming pointers.


-- 
Eric Botcazou
-------------- next part --------------
A non-text attachment was scrubbed...
Name: p.diff
Type: text/x-patch
Size: 17201 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/gcc-patches/attachments/20140415/2fbc43db/attachment.bin>