This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
[Bug rtl-optimization/42839] [4.5 Regression] gcc.target/mips/octeon-bbit-2.c failing for -mabi=64
- From: "steven at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 13 Feb 2010 11:39:13 -0000
- Subject: [Bug rtl-optimization/42839] [4.5 Regression] gcc.target/mips/octeon-bbit-2.c failing for -mabi=64
- References: <bug-42839-7151@http.gcc.gnu.org/bugzilla/>
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
------- Comment #10 from steven at gcc dot gnu dot org 2010-02-13 11:39 -------
In the test case of comment #2, the history of the funny PHIs is really odd. At
-O2 we end with this in the .optimized dump:
<bb 3>:
# i_1 = PHI <0(2)>
# s_11 = PHI <0(2)>
<bb 4>:
# i_12 = PHI <i_1(3), i_7(4)>
# s_13 = PHI <s_11(3), s_6(4)>
But the history of the phi of i_12 looks like this:
t.c.120t.reassoc2: # i_12 = PHI <i_7(3), 0(2)>
t.c.121t.vrp2: # i_12 = PHI <i_2(3), i_7(7)>
t.c.121t.vrp2: # i_12 = PHI <0(3), i_7(4)>
t.c.122t.dom2: # i_12 = PHI <0(3), i_7(4)>
t.c.123t.phicprop2: # i_12 = PHI <0(2), i_7(3)>
t.c.124t.cddce2: # i_12 = PHI <i_1(3), i_7(6)>
Somehow we have re-introduced the special PHI "# i_1 = PHI <0(2)>" in the
.cddce2 pass. The reason is that we created a loop pre-header.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42839