https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126178
Bug ID: 126178
Summary: ICE in extract_insn, at recog.cc:2894, -mflip-thumb
with __bf16
Product: gcc
Version: 17.0
Status: UNCONFIRMED
Keywords: ice-on-valid-code
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: mjires at gcc dot gnu.org
Target Milestone: ---
Target: arm-linux-gnueabi
Compiling reduced testcase llvm/clang/test/CodeGen/X86/bfloat-abi.c results in
ICE.
$ cat bfloat-abi.c
void hf() {}
void h2f(__bf16) {}
$ arm-linux-gnueabi-gcc bfloat-abi.c -mflip-thumb
bfloat-abi.c: In function ‘h2f’:
bfloat-abi.c:2:19: error: unrecognizable insn:
2 | void h2f(__bf16) {}
| ^
(insn 3 2 4 2 (set (mem/c:BF (reg/f:SI 94) [2 D.4770+0 S2 A16])
(reg:BF 0 r0 [ D.4770 ])) "bfloat-abi.c":2:18 -1
(nil))
during RTL pass: vregs
bfloat-abi.c:2:19: internal compiler error: in extract_insn, at recog.cc:2894
0x22b6cc1 internal_error(char const*, ...)
/home/mjires/git/GCC/master/gcc/diagnostic-global-context.cc:787
0x22c21a3 fancy_abort(char const*, int, char const*)
/home/mjires/git/GCC/master/gcc/diagnostics/context.cc:1813
0xf680d0 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
/home/mjires/git/GCC/master/gcc/rtl-error.cc:108
0xf680ef _fatal_insn_not_found(rtx_def const*, char const*, int, char const*)
/home/mjires/git/GCC/master/gcc/rtl-error.cc:116
0xf38e4a extract_insn(rtx_insn*)
/home/mjires/git/GCC/master/gcc/recog.cc:2894
0xb5ed68 instantiate_virtual_regs_in_insn
/home/mjires/git/GCC/master/gcc/function.cc:1611
0xb5ed68 instantiate_virtual_regs
/home/mjires/git/GCC/master/gcc/function.cc:1987
0xb5ed68 execute
/home/mjires/git/GCC/master/gcc/function.cc:2034
/home/mjires/built/master-arm-linux-gnueabi/libexec/gcc/arm-linux-gnueabi/17.0.0/cc1
-quiet bfloat-abi.c -quiet -dumpdir a- -dumpbase bfloat-abi.c -dumpbase-ext .c
-mflip-thumb -mcpu=arm10tdmi -mtls-dialect=gnu -marm -mlibarch=armv5t
-march=armv5t -o /tmp/cczERGgG.s
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
$ arm-linux-gnueabi-gcc -v
Using built-in specs.
COLLECT_GCC=arm-linux-gnueabi-gcc
COLLECT_LTO_WRAPPER=/home/mjires/built/master-arm-linux-gnueabi/libexec/gcc/arm-linux-gnueabi/17.0.0/lto-wrapper
Target: arm-linux-gnueabi
Configured with: /home/mjires/git/GCC/master/configure
--prefix=/home/mjires/built/master-arm-linux-gnueabi --target=arm-linux-gnueabi
--disable-bootstrap --enable-languages=c,c++,fortran --disable-multilib
--enable-checking : (reconfigured) /home/mjires/git/GCC/master/configure
--prefix=/home/mjires/built/master-arm-linux-gnueabi --target=arm-linux-gnueabi
--disable-bootstrap --disable-multilib --enable-checking
target_alias=arm-linux-gnueabi --enable-languages=c,c++,fortran,lto --no-create
--no-recursion
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 17.0.0 20260709 (experimental) (GCC)