Ping.
https://gcc.gnu.org/ml/gcc-patches/2016-12/msg00849.html
Thanks,
Kyrill
On 09/12/16 14:03, Kyrill Tkachov wrote:
Hi all,
In this ICE GCC reports invalid RTL sharing in the pattern:
(insn 955 954 956 (unspec_volatile [
(const:SI (unspec:SI [
(symbol_ref:SI ("a") [flags 0xe8] <var_decl 0x7fbb0d37cbd0
a>)
(const_int 4 [0x4])
] UNSPEC_TLS))
] VUNSPEC_POOL_4) -1
(nil))
seb.c:116:1: error: shared rtx
(const:SI (unspec:SI [
(symbol_ref:SI ("a") [flags 0xe8] <var_decl 0x7fbb0d37cbd0 a>)
(const_int 4 [0x4])
] UNSPEC_TLS))
This is the consttable_4 pattern emitted by dump_minipool and the shared rtx
that's causing
the problem is the operand to that pattern that comes from the 'value' field of
Mnode.
I'm not very familiar with the exact restrictions on sharing RTL but I believe
the right way
to fix these is to do a copy_rtx of the value we want to use. So this patch
does that when the
pool entries are emitted.
The ICE is quite fragile. See the PR for more details, but I've been able to
reliably reproduce it
on an arm-none-linux-gnueabihf target with -mcpu=arm7tdmi -mfloat-abi=soft
-mfpu=vfp -mthumb and this
patch fixes that there.
Bootstrapped and tested on arm-none-linux-gnueabihf.
Ok for trunk?
Thanks,
Kyrill
2016-12-09 Kyrylo Tkachov <kyrylo.tkac...@arm.com>
PR target/78694
* config/arm/arm.c (dump_minipool): Copy mp->value before emitting it
in the minipool to avoid invalid RTL sharing.
2016-12-09 Kyrylo Tkachov <kyrylo.tkac...@arm.com>
PR target/78694
* gcc.c-torture/compile/pr78694.c: New test.
