LoongArch

const LoongArch = extern struct {
    /// The numbered general-purpose registers r0 - r31. r0 must be zero.
    r: [32]Gpr,
    pc: Gpr,

    pub const Gpr = if (native_arch == .loongarch64) u64 else u32;

    pub inline fn current() LoongArch {
        var ctx: LoongArch = undefined;
        asm volatile (if (Gpr == u64)
                \\ st.d $zero, $t0, 0
                \\ st.d $ra, $t0, 8
                \\ st.d $tp, $t0, 16
                \\ st.d $sp, $t0, 24
                \\ st.d $a0, $t0, 32
                \\ st.d $a1, $t0, 40
                \\ st.d $a2, $t0, 48
                \\ st.d $a3, $t0, 56
                \\ st.d $a4, $t0, 64
                \\ st.d $a5, $t0, 72
                \\ st.d $a6, $t0, 80
                \\ st.d $a7, $t0, 88
                \\ st.d $t0, $t0, 96
                \\ st.d $t1, $t0, 104
                \\ st.d $t2, $t0, 112
                \\ st.d $t3, $t0, 120
                \\ st.d $t4, $t0, 128
                \\ st.d $t5, $t0, 136
                \\ st.d $t6, $t0, 144
                \\ st.d $t7, $t0, 152
                \\ st.d $t8, $t0, 160
                \\ st.d $r21, $t0, 168
                \\ st.d $fp, $t0, 176
                \\ st.d $s0, $t0, 184
                \\ st.d $s1, $t0, 192
                \\ st.d $s2, $t0, 200
                \\ st.d $s3, $t0, 208
                \\ st.d $s4, $t0, 216
                \\ st.d $s5, $t0, 224
                \\ st.d $s6, $t0, 232
                \\ st.d $s7, $t0, 240
                \\ st.d $s8, $t0, 248
                \\ bl 1f
                \\1:
                \\ st.d $ra, $t0, 256
            else
                \\ st.w $zero, $t0, 0
                \\ st.w $ra, $t0, 4
                \\ st.w $tp, $t0, 8
                \\ st.w $sp, $t0, 12
                \\ st.w $a0, $t0, 16
                \\ st.w $a1, $t0, 20
                \\ st.w $a2, $t0, 24
                \\ st.w $a3, $t0, 28
                \\ st.w $a4, $t0, 32
                \\ st.w $a5, $t0, 36
                \\ st.w $a6, $t0, 40
                \\ st.w $a7, $t0, 44
                \\ st.w $t0, $t0, 48
                \\ st.w $t1, $t0, 52
                \\ st.w $t2, $t0, 56
                \\ st.w $t3, $t0, 60
                \\ st.w $t4, $t0, 64
                \\ st.w $t5, $t0, 68
                \\ st.w $t6, $t0, 72
                \\ st.w $t7, $t0, 76
                \\ st.w $t8, $t0, 80
                \\ st.w $r21, $t0, 84
                \\ st.w $fp, $t0, 88
                \\ st.w $s0, $t0, 92
                \\ st.w $s1, $t0, 96
                \\ st.w $s2, $t0, 100
                \\ st.w $s3, $t0, 104
                \\ st.w $s4, $t0, 108
                \\ st.w $s5, $t0, 112
                \\ st.w $s6, $t0, 116
                \\ st.w $s7, $t0, 120
                \\ st.w $s8, $t0, 124
                \\ bl 1f
                \\1:
                \\ st.w $ra, $t0, 128
            :
            : [ctx] "{$r12}" (&ctx),
            : .{ .r1 = true, .memory = true });
        return ctx;
    }

    pub fn getFp(ctx: *const LoongArch) usize {
        return ctx.r[22];
    }
    pub fn getPc(ctx: *const LoongArch) usize {
        return ctx.pc;
    }

    pub fn dwarfRegisterBytes(ctx: *LoongArch, register_num: u16) DwarfRegisterError![]u8 {
        switch (register_num) {
            0...31 => return @ptrCast(&ctx.r[register_num]),
            64 => return @ptrCast(&ctx.pc),

            32...63 => return error.UnsupportedRegister, // f0 - f31

            else => return error.InvalidRegister,
        }
    }
}