This is an extern struct so that inline assembly in current can use field offsets.
const Lanai = extern struct
const Lanai = extern struct {
r: [32]Gpr,
pub const Gpr = u32;
pub inline fn current() Lanai {
var ctx: Lanai = undefined;
asm volatile (
\\ st %%r0, 0[r9]
\\ st %%r1, 4[r9]
\\ st %%r2, 8[r9]
\\ st %%r3, 12[r9]
\\ st %%r4, 16[r9]
\\ st %%r5, 20[r9]
\\ st %%r6, 24[r9]
\\ st %%r7, 28[r9]
\\ st %%r8, 32[r9]
\\ st %%r9, 36[r9]
\\ st %%r10, 40[r9]
\\ st %%r11, 44[r9]
\\ st %%r12, 48[r9]
\\ st %%r13, 52[r9]
\\ st %%r14, 56[r9]
\\ st %%r15, 60[r9]
\\ st %%r16, 64[r9]
\\ st %%r17, 68[r9]
\\ st %%r18, 72[r9]
\\ st %%r19, 76[r9]
\\ st %%r20, 80[r9]
\\ st %%r21, 84[r9]
\\ st %%r22, 88[r9]
\\ st %%r23, 92[r9]
\\ st %%r24, 96[r9]
\\ st %%r25, 100[r9]
\\ st %%r26, 104[r9]
\\ st %%r27, 108[r9]
\\ st %%r28, 112[r9]
\\ st %%r29, 116[r9]
\\ st %%r30, 120[r9]
\\ st %%r31, 124[r9]
:
: [ctx] "{r9}" (&ctx),
: .{ .memory = true });
return ctx;
}
pub fn getFp(ctx: *const Lanai) usize {
return ctx.r[5];
}
pub fn getPc(ctx: *const Lanai) usize {
return ctx.r[2];
}
pub fn dwarfRegisterBytes(ctx: *Lanai, register_num: u16) DwarfRegisterError![]u8 {
switch (register_num) {
0...31 => return @ptrCast(&ctx.s[register_num]),
else => return error.InvalidRegister,
}
}
}