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Date: Fri, 15 Oct 2004 23:59:00 -0000
Message-Id: <20041015.182844.91752452.kazu@cs.umass.edu>
To: gcc@gcc.gnu.org
Subject: Do we ever have a compound assignment like a = b = c?
From: Kazu Hirata <kazu@cs.umass.edu>
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Hi,

Assignment-related expanders like expand_assignment, store_expr, and
store_field can return rtx for the value being assgined to.  For
example, expand_assignment (b, c) would return the rtx of b.

Now, do we ever have an assignment embedded in something like
a = (b = c) or foo (a = b)?  I hear that we gimplify even at -O0.
Even after Temporary Expression Replacement, I don't see any 
assignment embedded in something.

If that's the case, I am thinking about removing the support for
returning rtx.  A lot of code would go away.

Kazu Hirata