1，ARM-64學習
New 64-bit general purpose registers(X0-X30), 32-bit(w0-w30)
AArch64 introduce the “zero” register, XZR and WZR(reads as 0,writes ignored)
Separate link registers(X30 and ELR_ELn)
Each exceptions level has its own stack pointer(SP_EL0, SP_EL1, SP_EL2, SP_EL3)
AArch64 does not have a direct equivalent of the AArch32 CPSR
The ARM 64-bit architecture also has a further thirty-two registers, v0-v31, which can be used by SIMD and
Floating-Point operations.
ARMv8 defines two security states: Secure and Non-secure, Normal word can only access non-secure physical address while secure world can access both
Physical address spaces.
ARMv8 virtual address space Applicatiion 0x0—0x0000FFFF FFFFFFFF (Application) 0x0000FFFF FFFFFFFF --0xFFFF0000 00000000(FAULT)
0xFFFF0000 00000000—0Xffffffff ffffffff(Peripherals and OS)
New 64-bit general purpose registers (X0 to X30)
Addressable in 32-bit forms (W0 to W30)
X30 = Link Register (LR)
X29 = Frame Pointer (FP)
2，
