[regression] Encoder crash for MCT-MC 5.1 at 32kHz/SWB in bw_detect_fx()

Basic info

• Float reference:
  • Encoder (float):
  • Decoder (float):
• Fixed point:
  • Encoder (fixed): 98e28d13
  • Decoder (fixed):

Bug description

The fixed point encoder crashes with an assert:

Assertion failed: (0), function L_shl, file basop32.c, line 2334.

Ways to reproduce

Box folder: ...\Box_EXTERNAL_IVAS_BASOP_VERIFICATION\issues\issue-1491

./IVAS_cod_fx -mc 5_1 -max_band SWB 96000 32 am2aa1s02_32.wav bit
# this crash occurs for all MCT bitrates i.e. from 96kbps to 512kbps