[Bug middle-end/42372] [4.5 regression] Regrename reuses non-dead register

[rearnsha at gcc dot gnu dot org]

------- Comment #5 from rearnsha at gcc dot gnu dot org  2009-12-16 11:11 -------
Regrename seems to be starting the scan of bb3 (from the reduced testcase) from
somewhere in the middle of the block rather than at the beginning (it's missing
at least 2 insns in the reg chain information:

Basic block 3:
Creating chain ip (0) at insn 71 (mark_write)
Closing chain ip (0) at insn 72 (terminate_write)
Creating chain ip (1) at insn 72 (mark_write)
Closing chain ip (1) at insn 73 (terminate_write)
Creating chain ip (2) at insn 73 (mark_write)
Closing chain ip (2) at insn 74 (terminate_dead)

but BB3 starts at insn 66, not 71 and in insn 68 a value is assigned to r6. 
However, this never seems to be considered.


-- 

rearnsha at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2
   Last reconfirmed|2009-12-14 23:37:08         |2009-12-16 11:11:57
               date|                            |
            Summary|Error: undefined symbol     |[4.5 regression] Regrename
                   |`.LPIC7' in operation       |reuses non-dead register


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42372