On 5/26/21 7:07 AM, Andrew Pinski wrote:
On Wed, May 26, 2021 at 2:01 AM Andrew Pinski <pins...@gmail.com> wrote:
On Wed, May 26, 2021 at 1:43 AM Bernd Edlinger
<bernd.edlin...@hotmail.de> wrote:
On 5/25/21 4:22 PM, Richard Biener via Gcc-patches wrote:
On Sun, May 23, 2021 at 12:03 PM apinski--- via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
From: Andrew Pinski <apin...@marvell.com>
Instead of some of the more manual optimizations inside phi-opt,
it would be good idea to do a lot of the heavy lifting inside match
and simplify instead. In the process, this moves the three simple
A?CST1:CST2 (where CST1 or CST2 is zero) simplifications.
OK? Boostrapped and tested on x86_64-linux-gnu with no regressions.
Differences from V1:
* Use bit_xor 1 instead of bit_not to fix the problem with boolean types
which are not 1 bit precision.
OK.
Thanks,
Richard.
Hmm, sorry, no luck.
I think this caused:
If anything it is a bad interaction with changes between r12-1046 and
r12-1053; I am suspecting a bug in those changes rather than my
changes causing the bug. Debugging it right now.
(gdb) p debug_tree(name)
<ssa_name 0x7ffff6a5cd38
type <boolean_type 0x7ffff6b45b28 _Bool public unsigned QI
size <integer_cst 0x7ffff6b2bdc8 constant 8>
unit-size <integer_cst 0x7ffff6b2bde0 constant 1>
align:8 warn_if_not_align:0 symtab:0 alias-set -1
canonical-type 0x7ffff6b45b28 precision:1 min <integer_cst
0x7ffff6b4a030 0> max <integer_cst 0x7ffff6b4a060 1>>
def_stmt _19 = ~_8;
version:19>
So what is happening is evrp converted:
ct_12 = ct_5 + -1;
Into
ct_12 = ct_5 == 1 ? 0 : 1;
(this was done before my patch)
And then it gets simplified to:
_8 = ct_5 == 1;
_19 = ~_8;
ct_12 = (int) _19;
(after my match.pd patch)
Which is correct, but the range code is not expecting new SSA names to
be added .....
It looks like the issue was introduced with r12-1048 (Add imports and
strengthen the export definition in range_def and gori_map).
I suspect there are other match.pd patterns which would also hit this
issue where a new ssa name is introduced.
I have no idea how to get this fixed because gimple-range-* is new to
me; I tried looking into it but calling has_def_chain/get_def_chain
inside register_dependency seems wrong, maybe Andrew MacLeod can help
here.
This happens even with a stage 1 gcc so it is not miscompiling.
Also sorry for the breakage, I was not expecting it this time around
as I ran bootstrap like three times and I did not expect an
interaction with other parts of the compiler like this.
Thanks,
Andrew Pinski
Yeah, not your fault, mine. I'm sure it would have shown up very soon
elsewhere, you were just the unlucky victim.
Sorry about that.
Andrew
