aarch64: mcontext_t struct is wrong in the mlibc ABI

[64]

No description provided.

[avdgrinten]

Wrong in what way?

[qookei]

The struct is defined here:

mlibc/abis/mlibc/signal.h

Lines 160 to 168 in a53280a

	typedef struct {
	unsigned long oldmask;
	unsigned long gregs[16];
	unsigned long pc, pr, sr;
	unsigned long gbr, mach, macl;
	unsigned long fpregs[16];
	unsigned long xfpregs[16];
	unsigned int fpscr, fpul, ownedfp;
	} mcontext_t;

AArch64 has 31 GPRs, PC (in this case stored in LR, aka X30), SP, 32 vector registers (which are 128 bits wide each), and 2 64-bit FP/SIMD control registers.

[64]

As per the discussion on Discord, this can be changed without a formal ABI break (but it might be a good idea to grep managarm sources for uses of this struct).