isSafeToSpeculativelyExecute() is always true for cast instructions, so remove this redundant check. Also try to simplify cast in similar way as for GEP and ADD with constant.

Try to simplify cast in similar way as for GEP and ADD with constant (e.g. sext/zext + trunc).

isSafeToSpeculativelyExecute() is always trueTry to simplify cast in similar way as for cast instructions, so remove this redundGEP and ADD with constant check(e.g. Also try to simplify cast in similar way as for GEP and ADD with constantsext/zext + trunc).