Function patch_seq_shl 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn patch_seq_shl(stack: Stack) -> Stack

Shift left

Stack effect: ( value count – result ) Shifts value left by count bits. Returns 0 for negative counts, counts >= 64, or any result that falls outside the 63-bit Int range. The 63-bit clamp matters because the tagged stack encoding would otherwise silently lose bit 62 when retagging an out-of-range i64.

Safety

Stack must have two Int values on top