TDecCAVLC.cpp, line 922 is the signed Golomb decode function which calls the unsigned decode function xReadEpExGolomb on line 2197.
This function does not match the text, or the CABAC counterpart in TDecSbac.ccp on line 285:

Void TDecCavlc::xReadEpExGolomb( UInt& ruiSymbol, UInt uiCount )
{
  UInt uiSymbol = 0;
  UInt uiBit = 1;
  
  
  while( uiBit )
  {
    xReadFlag( uiBit );
    uiSymbol += uiBit << uiCount++;
  }
  
  uiCount--;
  while( uiCount-- )
  {
    xReadFlag( uiBit );
    uiSymbol += uiBit << uiCount; // This shift is wrong
  }
  
  ruiSymbol = uiSymbol;
  
  return;
}

Text:

q = −1
codeNum = 0
bit = 1
while( bit ){

bit = read_bits( 1 )
q++

}
for(a = 0; a < k; ++a){

bit = read_bits( 1 )
if( bit )

codeNum += (1 << a)

}
codeNum += q << k

---- Below not part of the function ----

if( codeNum != 0 ) {

bit = read_bits( 1 )
codeNum = ( bit ) ? codeNum : ( −codeNum )

}

The function xGolombDecode on line 922 should just be re-written to match the text, and not call xReadEpExGolomb (which can just be removed all together).