------- Comment #1 from zadeck at naturalbridge dot com 2008-05-08 16:46
-------
Subject: Re: [4.4 Regression] g++.dg/tree-ssa/pr19637.C
ICEs with 135041 -> 135057
Here is the bug. I do not know if this is just an illegal insn
generated by a bad port or if we are missing something in the dce code.
the dce code is deleting insn 12:
(call_insn/u 12 11 47 2
/home/zadeck/gcc36177/gcc/testsuite/g++.dg/opt/pr23714.C:11 (parallel [
(set (reg:SF 10 r10)
(call (mem:QI (reg/f:SI 31) [0 S1 A8])
(const_int 0 [0x0])))
(clobber (reg:SI 16 srp))
]) 224 {*expanded_call_value_non_v32} (expr_list:REG_EH_REGION
(const_int 1 [0x1])
(nil))
(expr_list:REG_DEP_TRUE (use (reg:SF 11 r11))
(expr_list:REG_DEP_TRUE (use (reg:SF 10 r10))
(nil))))
I would have thought that since this can generate an exception and it is
a call insn that it would have been declared as a non deleteable insn by
dce.c:deleteable_insn_p. It is also clearly a jump insn even though we
do not see it as such since it is buried in a parallel.
In particular, i assume that the dce code is getting confused because it
does not see the call inside the parallel.
i do not know if this is a bug in the cris port or if there are other
cases that need to be added to dce. This is for the rtl trained
professionals to determine.
kenny
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36177
