Use OpCC only for 32-bit compares.

This fixes backend/sparc_cmp.c.
Zero-extend left operand of an Shr node.

This fixes backend/sparc_shr.c.
Simplify offset/size calculation in default_layout_compound_type().

Just one variable to hold them is sufficient.
Reduce code duplication in foreach_ir_edgeset().
Add and use the helper function is_tls_entity().
Remove get_firm_object_size().

Its only use is pointless.
The following call to FormatFirmObject() detects the same problem.
Remove get_mode_name_ex().

Just use get_mode_name() instead.
Remove union type_or_ent.
Implement a better way to correctly Mux two constants.
Remove redundant assignment.
Remove redundant check.
Factorise common code to skip whitespace.
Remove remnant of name SymConst.
Rename several symconst to address/callee/entity.
Simplify printing entity+offset.
Use new_r_*(...) instead of new_rd_*(NULL, ...).
Cleanup and use C99.
Split SymConst into EntConst and TypeConst.

This removes the strange entity/type duality and we get rid of union symconst_symbol.