What to remove after tree-ssa is merged?

[S. Bosscher]

The reasoning so far has been: If it can be expressed in RTL,
then there has to be an equivalent representation in trees.
So basically we hope that PLACEHOLDER_EXPRs can be expanded
to an equivalent tree without PLACEHOLDER_EXPPs, i.e. making
this node an Ada language-specific tree node.  If it is
impossble to represent the semantics of a PLACEHOLDER_EXPR
in a lowered tree, then we'll have to revisit this issue.

Gr.
Steven


-----Original Message-----
From: kenner@vlsi1.ultra.nyu.edu
To: pinskia@physics.uc.edu
Cc: gcc@gcc.gnu.org
Sent: 2/4/04 3:39 PM
Subject: Re: What to remove after tree-ssa is merged?

    Should really PLACEHOLDER_EXPR be done in the front-end
    and be expanded to what it really does in gimplify stage
    which every other language needs to do with its language
    specific trees.

Read the documentation and explain what you propose expanding it *to*.
There's no way to express the needed semantics without this or something
very similar.