如何将无符号24位int转换为有符号int并将符号扩展为32位?

I'm attemting to encode the branch instruction of the ARM architecture into a printout (converting a 32bit number into assembly). For the Branch instruction. I have to extend a signed_immed_24 value to 32 bits and shift left to obtain the value for the assembly code.I'm attemting to encode the branch instruction