[Bug target/112853] New: RISC-V: RVV: SPEC2017 525.x264 regression

[vineetg at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112853

            Bug ID: 112853
           Summary: RISC-V: RVV: SPEC2017 525.x264 regression
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: vineetg at gcc dot gnu.org
                CC: juzhe.zhong at rivai dot ai, patrick at rivosinc dot com,
                    rdapp at gcc dot gnu.org
  Target Milestone: ---

As of commit 3d104d93a701 ("ARC: Consistent use of whitespace in assembler
templates.") x264 build for RVV is segfaulting.

```
QEMU_CPU=rv64,vlen=256,zba=true,zbb=true,zbs=true,zicond=true,vext_spec=v1.0,Zve32f=true,Zve64f=true
qemu-riscv64  ./ldecod_r_base.rivos_rv64-m64 -i BuckBunny.264 -o BuckBunny.yuv

Setting Default Parameters...
Parsing Configfile decoder.cfg

----------------------------- JM 17.1 (FRExt) -----------------------------
--------------------------------------------------------------------------
 Input H.264 bitstream                  : BuckBunny.264 
 Output decoded YUV                     : BuckBunny.yuv 
 Input reference file                   : test_rec.yuv 
--------------------------------------------------------------------------
POC must = frame# or field# for SNRs to be correct
--------------------------------------------------------------------------
  Frame          POC  Pic#   QP    SnrY     SnrU     SnrV   Y:U:V Time(ms)
--------------------------------------------------------------------------
 Input reference file                   : test_rec.yuv does not exist 
                                          SNR values are not available
Segmentation fault (core dumped)
```

It was fine at my prev checkpoint: 
2023-11-22 6f59f959e751 hppa: Define MAX_FIXED_MODE_SIZE

Built with following flags

-Ofast -fno-lto -static -march=rv64gcv_zba_zbb_zbc_zbs_zicond -ftree-vectorize
--param=riscv-autovec-preference=scalable