COOL Compiler for AArch64

Repo

There're several things to share after I changed target code generation of COOL Compiler from MIPS32 to AArch64.

First of all, I learned basic instructions of AArch64 and how to cross compile COOL codes into AArch64 assembly codes via dockcross.

Secondly, "Alignment" is so important from 32-bit system to 64-bit system, especially stack pointer in AArch64.

Thirdly, "watch" in gdb is helpful while debugging segmentation faults.

Finally, I appreciate CS143 Compilers, which is a very wonderful course.

Thanks~