vhdl: move sem* packages to vhdl children.

1 files changed, 36 insertions, 0 deletions

diff --git a/src/vhdl/vhdl-sem_inst.ads b/src/vhdl/vhdl-sem_inst.ads
new file mode 100644
index 000000000..48d72b770
--- /dev/null
+++ b/src/vhdl/vhdl-sem_inst.ads
@@ -0,0 +1,36 @@
+--  Package (and subprograms) instantiations
+
+--  When a package is instantiated, we need to 'duplicate' its declaration.
+--  This looks useless for analysis but it isn't: a type from a package
+--  instantiated twice declares two different types.  Without duplication, we
+--  need to attach to each declaration its instance, which looks more expansive
+--  that duplicating the declaration.
+--
+--  Furthermore, for generic type interface, it looks a good idea to duplicate
+--  the body (macro expansion).
+--
+--  Duplicating is not trivial: internal links must be kept and external
+--  links preserved.  A table is used to map nodes from the uninstantiated
+--  package to its duplicated node.  Links from instantiated declaration to
+--  the original declaration are also stored in that table.
+
+with Iirs; use Iirs;
+
+package Vhdl.Sem_Inst is
+   --  Return the origin of node N, the node from which N was instantiated.
+   --  If N is not an instance, this function returns Null_Iir.
+   function Get_Origin (N : Iir) return Iir;
+
+   --  Create declaration chain and generic declarations for INST from PKG.
+   procedure Instantiate_Package_Declaration (Inst : Iir; Pkg : Iir);
+
+   --  Return the instantiation of the body for INST, ie macro-expand the
+   --  body.  INST has the form of a generic-mapped package.
+   function Instantiate_Package_Body (Inst : Iir) return Iir;
+
+   --  In CHAIN, substitute all references to E by REP.
+   procedure Substitute_On_Chain (Chain : Iir; E : Iir; Rep : Iir);
+
+   --  Deep copy of ORIG.  Doesn't change location.
+   function Copy_Tree (Orig : Iir) return Iir;
+end Vhdl.Sem_Inst;