On 10/26/2012 12:30 AM, Alexandre Oliva wrote:
Propagate debug stmts for jump threading
From: Alexandre Oliva<lxol...@fsfla.org>
for gcc/ChangeLog
PR debug/54693
* tree-ssa-threadedge.c (thread_around_empty_block): Copy
debug temps from predecessor before threading.
So my only concerns here are what happens when we copy the debug
statements, but end up not threading the jump. At this stage we're just
recording the jump threading opportunities; only a subset of the
registered jump threading opportunities will be optimized.
So will these new debug statements cause problems if the jump isn't
threaded? Closely related, do these new debug statements need to be
rewritten into SSA form? If so we have a problem if we copy the debug
statements, but ultimately thread no jumps at all. In that scenario we
don't update the SSA graph.
jeff
