This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
[Bug target/43187] unnecessary register spill
- From: "rearnsha at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 26 Feb 2010 14:39:03 -0000
- Subject: [Bug target/43187] unnecessary register spill
- References: <bug-43187-17659@http.gcc.gnu.org/bugzilla/>
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
------- Comment #1 from rearnsha at gcc dot gnu dot org 2010-02-26 14:39 -------
I don't think this test case is valid.
Unfortunately, the division function is not completely pure. If a division by
zero occurs, then a handler function may be invoked, which might cause the
contents pointed to by p to modified (external views of *p need not be const).
So we have to preserve the values previously loaded.
Of course, the order in which parameters are marshalled in a function call are
unspecified in C, but that doesn't affect the overall analysis.
--
rearnsha at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |rearnsha at gcc dot gnu dot
| |org
Status|UNCONFIRMED |RESOLVED
Resolution| |INVALID
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43187