https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116139
Bug ID: 116139
Summary: [15 Regression] ICE with --param fully-pipelined-fma=1
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Keywords: ice-on-valid-code
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: ktkachov at gcc dot gnu.org
Target Milestone: ---
Target: aarch64
The testcase gcc.dg/pr110279-2.c ICEs when compiled with -Ofast
-mcpu=neoverse-v2 --param fully-pipelined-fma=1
during GIMPLE pass: reassoc
ice.c: In function ‘foo’:
ice.c:10:1: internal compiler error: in get_reassociation_width, at
tree-ssa-reassoc.cc:5520
10 | foo (data_e in)
| ^~~
0x20eab57 internal_error(char const*, ...)
$SRC/gcc/diagnostic-global-context.cc:491
0x7b014f fancy_abort(char const*, int, char const*)
$SRC/gcc/diagnostic.cc:1725
0x118eefb get_reassociation_width
$SRC/gcc/tree-ssa-reassoc.cc:5520
0x11a047b reassociate_bb
$SRC/gcc/tree-ssa-reassoc.cc:7223
0x119fda7 reassociate_bb
$SRC/gcc/tree-ssa-reassoc.cc:7277
0x119fda7 reassociate_bb
$SRC/gcc/tree-ssa-reassoc.cc:7277
0x11a2b27 do_reassoc
$SRC/gcc/tree-ssa-reassoc.cc:7389
0x11a2b27 execute_reassoc
$SRC/gcc/tree-ssa-reassoc.cc:7479
0x11a2b27 execute
$SRC/gcc/tree-ssa-reassoc.cc:7520
Please submit a full bug report, with preprocessed source (by using
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It hits the assert at:
5512 Find out if we can get a smaller width considering FMA. */
5513 if (width > 1 && mult_num && param_fully_pipelined_fma)
5514 {
5515 /* When param_fully_pipelined_fma is set, assume FMUL and FMA use
the
5516 same units that can also do FADD. For other scenarios, such as
when
5517 FMUL and FADD are using separated units, the following code may
not
5518 appy. */
5519 int width_mult = targetm.sched.reassociation_width (MULT_EXPR,
mode);
5520 gcc_checking_assert (width_mult <= width);
I think this shouldn't be an assert but rather a condition in the if statement
on line 5513?
