This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: [RFC] Contributing tree-ssa to mainline
On Jan 19, 2004, at 12:51, Diego Novillo wrote:
Instead of emitting runtime calls, would it be possible to emit tree
codes with well defined semantics? On finding them, the optimizers
would know that it's not just an arbitrary function call for instance
(perhaps adding attributes to the libcall).
But I'm oversimplifying. We would have to talk about specific cases.
There are definitely cases where we should do this. For example,
for overflow checks in integer addition and multiplication, we now
use a wider type for the arithmetic (or library routines for wide types)
and check the result against bounds. Having tree codes with
language-defined overflow semantics would allow the back end to
expand to proper instructions with trap-on-overflow or jump on
condition code. How does Java deal with this issue?
-Geert