stage2: remove SPU Mark II backend

As it stands, the backend is incomplete, and there is no active contributor,
making it dead weight.

However, anyone is free to resurrect this backend at any time.

1 files changed, 0 insertions, 170 deletions

diff --git a/src/codegen/spu-mk2.zig b/src/codegen/spu-mk2.zig
deleted file mode 100644
index 542862caca..0000000000
--- a/src/codegen/spu-mk2.zig
+++ /dev/null
@@ -1,170 +0,0 @@
-const std = @import("std");
-
-pub const Interpreter = @import("spu-mk2/interpreter.zig").Interpreter;
-
-pub const ExecutionCondition = enum(u3) {
-    always = 0,
-    when_zero = 1,
-    not_zero = 2,
-    greater_zero = 3,
-    less_than_zero = 4,
-    greater_or_equal_zero = 5,
-    less_or_equal_zero = 6,
-    overflow = 7,
-};
-
-pub const InputBehaviour = enum(u2) {
-    zero = 0,
-    immediate = 1,
-    peek = 2,
-    pop = 3,
-};
-
-pub const OutputBehaviour = enum(u2) {
-    discard = 0,
-    push = 1,
-    jump = 2,
-    jump_relative = 3,
-};
-
-pub const Command = enum(u5) {
-    copy = 0,
-    ipget = 1,
-    get = 2,
-    set = 3,
-    store8 = 4,
-    store16 = 5,
-    load8 = 6,
-    load16 = 7,
-    undefined0 = 8,
-    undefined1 = 9,
-    frget = 10,
-    frset = 11,
-    bpget = 12,
-    bpset = 13,
-    spget = 14,
-    spset = 15,
-    add = 16,
-    sub = 17,
-    mul = 18,
-    div = 19,
-    mod = 20,
-    @"and" = 21,
-    @"or" = 22,
-    xor = 23,
-    not = 24,
-    signext = 25,
-    rol = 26,
-    ror = 27,
-    bswap = 28,
-    asr = 29,
-    lsl = 30,
-    lsr = 31,
-};
-
-pub const Instruction = packed struct {
-    condition: ExecutionCondition,
-    input0: InputBehaviour,
-    input1: InputBehaviour,
-    modify_flags: bool,
-    output: OutputBehaviour,
-    command: Command,
-    reserved: u1 = 0,
-
-    pub fn format(instr: Instruction, comptime fmt: []const u8, options: std.fmt.FormatOptions, out: anytype) !void {
-        try std.fmt.format(out, "0x{x:0<4} ", .{@bitCast(u16, instr)});
-        try out.writeAll(switch (instr.condition) {
-            .always => "    ",
-            .when_zero => "== 0",
-            .not_zero => "!= 0",
-            .greater_zero => " > 0",
-            .less_than_zero => " < 0",
-            .greater_or_equal_zero => ">= 0",
-            .less_or_equal_zero => "<= 0",
-            .overflow => "ovfl",
-        });
-        try out.writeAll(" ");
-        try out.writeAll(switch (instr.input0) {
-            .zero => "zero",
-            .immediate => "imm ",
-            .peek => "peek",
-            .pop => "pop ",
-        });
-        try out.writeAll(" ");
-        try out.writeAll(switch (instr.input1) {
-            .zero => "zero",
-            .immediate => "imm ",
-            .peek => "peek",
-            .pop => "pop ",
-        });
-        try out.writeAll(" ");
-        try out.writeAll(switch (instr.command) {
-            .copy => "copy     ",
-            .ipget => "ipget    ",
-            .get => "get      ",
-            .set => "set      ",
-            .store8 => "store8   ",
-            .store16 => "store16  ",
-            .load8 => "load8    ",
-            .load16 => "load16   ",
-            .undefined0 => "undefined",
-            .undefined1 => "undefined",
-            .frget => "frget    ",
-            .frset => "frset    ",
-            .bpget => "bpget    ",
-            .bpset => "bpset    ",
-            .spget => "spget    ",
-            .spset => "spset    ",
-            .add => "add      ",
-            .sub => "sub      ",
-            .mul => "mul      ",
-            .div => "div      ",
-            .mod => "mod      ",
-            .@"and" => "and      ",
-            .@"or" => "or       ",
-            .xor => "xor      ",
-            .not => "not      ",
-            .signext => "signext  ",
-            .rol => "rol      ",
-            .ror => "ror      ",
-            .bswap => "bswap    ",
-            .asr => "asr      ",
-            .lsl => "lsl      ",
-            .lsr => "lsr      ",
-        });
-        try out.writeAll(" ");
-        try out.writeAll(switch (instr.output) {
-            .discard => "discard",
-            .push => "push   ",
-            .jump => "jmp    ",
-            .jump_relative => "rjmp   ",
-        });
-        try out.writeAll(" ");
-        try out.writeAll(if (instr.modify_flags)
-            "+ flags"
-        else
-            "       ");
-    }
-};
-
-pub const FlagRegister = packed struct {
-    zero: bool,
-    negative: bool,
-    carry: bool,
-    carry_enabled: bool,
-    interrupt0_enabled: bool,
-    interrupt1_enabled: bool,
-    interrupt2_enabled: bool,
-    interrupt3_enabled: bool,
-    reserved: u8 = 0,
-};
-
-pub const Register = enum {
-    dummy,
-
-    pub fn allocIndex(self: Register) ?u4 {
-        return null;
-    }
-};
-
-pub const callee_preserved_regs = [_]Register{};