Commit 8c664d3f6a
Changed files (1)
src
arch
x86_64
src/arch/x86_64/Emit.zig
@@ -193,8 +193,7 @@ fn mirNop(emit: *Emit) InnerError!void {
}
fn mirSyscall(emit: *Emit) InnerError!void {
- const encoder = try Encoder.init(emit.code, 2);
- encoder.opcode_2byte(0x0f, 0x05);
+ return lowerToZoEnc(.syscall, emit.code);
}
fn mirPushPop(emit: *Emit, tag: Tag, inst: Mir.Inst.Index) InnerError!void {
@@ -470,6 +469,7 @@ const Tag = enum {
@"test",
brk,
nop,
+ syscall,
ret_near,
ret_far,
};
@@ -509,78 +509,104 @@ const Encoding = enum {
td,
};
-inline fn getOpCode(tag: Tag, enc: Encoding) ?u8 {
+const OpCode = union(enum) {
+ one_byte: u8,
+ two_byte: struct { _1: u8, _2: u8 },
+
+ fn oneByte(opc: u8) OpCode {
+ return .{ .one_byte = opc };
+ }
+
+ fn twoByte(opc1: u8, opc2: u8) OpCode {
+ return .{ .two_byte = .{ ._1 = opc1, ._2 = opc2 } };
+ }
+
+ fn encode(opc: OpCode, encoder: Encoder) void {
+ switch (opc) {
+ .one_byte => |v| encoder.opcode_1byte(v),
+ .two_byte => |v| encoder.opcode_2byte(v._1, v._2),
+ }
+ }
+
+ fn encodeWithReg(opc: OpCode, encoder: Encoder, reg: Register) void {
+ assert(opc == .one_byte);
+ encoder.opcode_withReg(opc.one_byte, reg.lowId());
+ }
+};
+
+inline fn getOpCode(tag: Tag, enc: Encoding, is_one_byte: bool) ?OpCode {
switch (enc) {
.zo => return switch (tag) {
- .ret_near => 0xc3,
- .ret_far => 0xcb,
- .brk => 0xcc,
- .nop => 0x90,
+ .ret_near => OpCode.oneByte(0xc3),
+ .ret_far => OpCode.oneByte(0xcb),
+ .brk => OpCode.oneByte(0xcc),
+ .nop => OpCode.oneByte(0x90),
+ .syscall => OpCode.twoByte(0x0f, 0x05),
else => null,
},
.d => return switch (tag) {
- .jmp_near => 0xe9,
- .call_near => 0xe8,
+ .jmp_near => OpCode.oneByte(0xe9),
+ .call_near => OpCode.oneByte(0xe8),
else => null,
},
.m => return switch (tag) {
- .jmp_near, .call_near, .push => 0xff,
- .pop => 0x8f,
+ .jmp_near, .call_near, .push => OpCode.oneByte(0xff),
+ .pop => OpCode.oneByte(0x8f),
else => null,
},
.o => return switch (tag) {
- .push => 0x50,
- .pop => 0x58,
+ .push => OpCode.oneByte(0x50),
+ .pop => OpCode.oneByte(0x58),
else => null,
},
.i => return switch (tag) {
- .push => 0x68,
- .@"test" => 0xa9,
- .ret_near => 0xc2,
- .ret_far => 0xca,
+ .push => OpCode.oneByte(if (is_one_byte) 0x6a else 0x68),
+ .@"test" => OpCode.oneByte(if (is_one_byte) 0xa8 else 0xa9),
+ .ret_near => OpCode.oneByte(0xc2),
+ .ret_far => OpCode.oneByte(0xca),
else => null,
},
.mi => return switch (tag) {
- .adc, .add, .sub, .xor, .@"and", .@"or", .sbb, .cmp => 0x81,
- .mov => 0xc7,
- .@"test" => 0xf7,
+ .adc, .add, .sub, .xor, .@"and", .@"or", .sbb, .cmp => OpCode.oneByte(if (is_one_byte) 0x80 else 0x81),
+ .mov => OpCode.oneByte(if (is_one_byte) 0xc6 else 0xc7),
+ .@"test" => OpCode.oneByte(if (is_one_byte) 0xf6 else 0xf7),
else => null,
},
.mr => return switch (tag) {
- .adc => 0x11,
- .add => 0x01,
- .sub => 0x29,
- .xor => 0x31,
- .@"and" => 0x21,
- .@"or" => 0x09,
- .sbb => 0x19,
- .cmp => 0x39,
- .mov => 0x89,
+ .adc => OpCode.oneByte(if (is_one_byte) 0x10 else 0x11),
+ .add => OpCode.oneByte(if (is_one_byte) 0x00 else 0x01),
+ .sub => OpCode.oneByte(if (is_one_byte) 0x28 else 0x29),
+ .xor => OpCode.oneByte(if (is_one_byte) 0x30 else 0x31),
+ .@"and" => OpCode.oneByte(if (is_one_byte) 0x20 else 0x21),
+ .@"or" => OpCode.oneByte(if (is_one_byte) 0x08 else 0x09),
+ .sbb => OpCode.oneByte(if (is_one_byte) 0x18 else 0x19),
+ .cmp => OpCode.oneByte(if (is_one_byte) 0x38 else 0x39),
+ .mov => OpCode.oneByte(if (is_one_byte) 0x88 else 0x89),
else => null,
},
.rm => return switch (tag) {
- .adc => 0x13,
- .add => 0x03,
- .sub => 0x2b,
- .xor => 0x33,
- .@"and" => 0x23,
- .@"or" => 0x0b,
- .sbb => 0x1b,
- .cmp => 0x3b,
- .mov => 0x8b,
- .lea => 0x8d,
+ .adc => OpCode.oneByte(if (is_one_byte) 0x12 else 0x13),
+ .add => OpCode.oneByte(if (is_one_byte) 0x02 else 0x03),
+ .sub => OpCode.oneByte(if (is_one_byte) 0x2a else 0x2b),
+ .xor => OpCode.oneByte(if (is_one_byte) 0x32 else 0x33),
+ .@"and" => OpCode.oneByte(if (is_one_byte) 0x22 else 0x23),
+ .@"or" => OpCode.oneByte(if (is_one_byte) 0x0b else 0x0b),
+ .sbb => OpCode.oneByte(if (is_one_byte) 0x1a else 0x1b),
+ .cmp => OpCode.oneByte(if (is_one_byte) 0x3a else 0x3b),
+ .mov => OpCode.oneByte(if (is_one_byte) 0x8a else 0x8b),
+ .lea => OpCode.oneByte(if (is_one_byte) 0x8c else 0x8d),
else => null,
},
.oi => return switch (tag) {
- .mov => 0xb8,
+ .mov => OpCode.oneByte(if (is_one_byte) 0xb0 else 0xb8),
else => null,
},
.fd => return switch (tag) {
- .mov => 0xa1,
+ .mov => OpCode.oneByte(if (is_one_byte) 0xa0 else 0xa1),
else => null,
},
.td => return switch (tag) {
- .mov => 0xa3,
+ .mov => OpCode.oneByte(if (is_one_byte) 0xa2 else 0xa3),
else => null,
},
}
@@ -648,32 +674,25 @@ const RegisterOrMemory = union(enum) {
};
fn lowerToZoEnc(tag: Tag, code: *std.ArrayList(u8)) InnerError!void {
- const opc = getOpCode(tag, .zo).?;
+ const opc = getOpCode(tag, .zo, false).?;
const encoder = try Encoder.init(code, 1);
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
}
fn lowerToIEnc(tag: Tag, imm: i32, code: *std.ArrayList(u8)) InnerError!void {
- var opc = getOpCode(tag, .i).?;
if (tag == .ret_far or tag == .ret_near) {
const encoder = try Encoder.init(code, 3);
- encoder.opcode_1byte(opc);
+ const opc = getOpCode(tag, .i, false).?;
+ opc.encode(encoder);
encoder.imm16(@intCast(i16, imm));
return;
}
- if (immOpSize(imm) == 8) {
- // TODO I think getOpCode should track this
- switch (tag) {
- .push => opc += 2,
- .@"test" => opc -= 1,
- else => return error.EmitFail,
- }
- }
+ const opc = getOpCode(tag, .i, immOpSize(imm) == 8).?;
const encoder = try Encoder.init(code, 5);
if (immOpSize(imm) == 16) {
encoder.opcode_1byte(0x66);
}
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (immOpSize(imm) == 8) {
encoder.imm8(@intCast(i8, imm));
} else if (immOpSize(imm) == 16) {
@@ -685,7 +704,7 @@ fn lowerToIEnc(tag: Tag, imm: i32, code: *std.ArrayList(u8)) InnerError!void {
fn lowerToOEnc(tag: Tag, reg: Register, code: *std.ArrayList(u8)) InnerError!void {
if (reg.size() != 16 and reg.size() != 64) return error.EmitFail; // TODO correct for push/pop, but is it universal?
- const opc = getOpCode(tag, .o).?;
+ const opc = getOpCode(tag, .o, false).?;
const encoder = try Encoder.init(code, 3);
if (reg.size() == 16) {
encoder.opcode_1byte(0x66);
@@ -694,18 +713,18 @@ fn lowerToOEnc(tag: Tag, reg: Register, code: *std.ArrayList(u8)) InnerError!voi
.w = false,
.b = reg.isExtended(),
});
- encoder.opcode_withReg(opc, reg.lowId());
+ opc.encodeWithReg(encoder, reg);
}
fn lowerToDEnc(tag: Tag, imm: i32, code: *std.ArrayList(u8)) InnerError!void {
- const opc = getOpCode(tag, .d).?;
+ const opc = getOpCode(tag, .d, false).?;
const encoder = try Encoder.init(code, 5);
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
encoder.imm32(imm);
}
fn lowerToMEnc(tag: Tag, reg_or_mem: RegisterOrMemory, code: *std.ArrayList(u8)) InnerError!void {
- const opc = getOpCode(tag, .m).?;
+ const opc = getOpCode(tag, .m, false).?;
const modrm_ext = getModRmExt(tag).?;
switch (reg_or_mem) {
.register => |reg| {
@@ -715,7 +734,7 @@ fn lowerToMEnc(tag: Tag, reg_or_mem: RegisterOrMemory, code: *std.ArrayList(u8))
.w = false,
.b = reg.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
encoder.modRm_direct(modrm_ext, reg.lowId());
},
.memory => |mem_op| {
@@ -726,7 +745,7 @@ fn lowerToMEnc(tag: Tag, reg_or_mem: RegisterOrMemory, code: *std.ArrayList(u8))
.w = false,
.b = reg.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (reg.lowId() == 4) {
if (mem_op.disp == 0) {
encoder.modRm_SIBDisp0(modrm_ext);
@@ -752,7 +771,7 @@ fn lowerToMEnc(tag: Tag, reg_or_mem: RegisterOrMemory, code: *std.ArrayList(u8))
}
}
} else {
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (mem_op.rip) {
encoder.modRm_RIPDisp32(modrm_ext);
} else {
@@ -776,10 +795,10 @@ fn lowerToFdEnc(tag: Tag, reg: Register, moffs: i64, code: *std.ArrayList(u8)) I
fn lowerToTdFdEnc(tag: Tag, reg: Register, moffs: i64, code: *std.ArrayList(u8), td: bool) InnerError!void {
if (reg.lowId() != Register.rax.lowId()) return error.EmitFail;
if (reg.size() != immOpSize(moffs)) return error.EmitFail;
- var opc = if (td) getOpCode(tag, .td).? else getOpCode(tag, .fd).?;
- if (reg.size() == 8) {
- opc -= 1;
- }
+ const opc = if (td)
+ getOpCode(tag, .td, reg.size() == 8).?
+ else
+ getOpCode(tag, .fd, reg.size() == 8).?;
const encoder = try Encoder.init(code, 10);
if (reg.size() == 16) {
encoder.opcode_1byte(0x66);
@@ -787,7 +806,7 @@ fn lowerToTdFdEnc(tag: Tag, reg: Register, moffs: i64, code: *std.ArrayList(u8),
encoder.rex(.{
.w = reg.size() == 64,
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
switch (reg.size()) {
8 => {
const moffs8 = try math.cast(i8, moffs);
@@ -809,11 +828,8 @@ fn lowerToTdFdEnc(tag: Tag, reg: Register, moffs: i64, code: *std.ArrayList(u8),
}
fn lowerToOiEnc(tag: Tag, reg: Register, imm: i64, code: *std.ArrayList(u8)) InnerError!void {
- var opc = getOpCode(tag, .oi).?;
if (reg.size() != immOpSize(imm)) return error.EmitFail;
- if (reg.size() == 8) {
- opc -= 8;
- }
+ const opc = getOpCode(tag, .oi, reg.size() == 8).?;
const encoder = try Encoder.init(code, 10);
if (reg.size() == 16) {
encoder.opcode_1byte(0x66);
@@ -822,7 +838,7 @@ fn lowerToOiEnc(tag: Tag, reg: Register, imm: i64, code: *std.ArrayList(u8)) Inn
.w = reg.size() == 64,
.b = reg.isExtended(),
});
- encoder.opcode_withReg(opc, reg.lowId());
+ opc.encodeWithReg(encoder, reg);
switch (reg.size()) {
8 => {
const imm8 = try math.cast(i8, imm);
@@ -844,13 +860,10 @@ fn lowerToOiEnc(tag: Tag, reg: Register, imm: i64, code: *std.ArrayList(u8)) Inn
}
fn lowerToMiEnc(tag: Tag, reg_or_mem: RegisterOrMemory, imm: i32, code: *std.ArrayList(u8)) InnerError!void {
- var opc = getOpCode(tag, .mi).?;
const modrm_ext = getModRmExt(tag).?;
switch (reg_or_mem) {
.register => |dst_reg| {
- if (dst_reg.size() == 8) {
- opc -= 1;
- }
+ const opc = getOpCode(tag, .mi, dst_reg.size() == 8).?;
const encoder = try Encoder.init(code, 7);
if (dst_reg.size() == 16) {
// 0x66 prefix switches to the non-default size; here we assume a switch from
@@ -862,7 +875,7 @@ fn lowerToMiEnc(tag: Tag, reg_or_mem: RegisterOrMemory, imm: i32, code: *std.Arr
.w = dst_reg.size() == 64,
.b = dst_reg.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
encoder.modRm_direct(modrm_ext, dst_reg.lowId());
switch (dst_reg.size()) {
8 => {
@@ -878,6 +891,7 @@ fn lowerToMiEnc(tag: Tag, reg_or_mem: RegisterOrMemory, imm: i32, code: *std.Arr
}
},
.memory => |dst_mem| {
+ const opc = getOpCode(tag, .mi, false).?;
const encoder = try Encoder.init(code, 12);
if (dst_mem.reg) |dst_reg| {
// Register dst_reg can either be 64bit or 32bit in size.
@@ -891,7 +905,7 @@ fn lowerToMiEnc(tag: Tag, reg_or_mem: RegisterOrMemory, imm: i32, code: *std.Arr
.w = false,
.b = dst_reg.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (dst_reg.lowId() == 4) {
if (dst_mem.disp == 0) {
encoder.modRm_SIBDisp0(modrm_ext);
@@ -917,7 +931,7 @@ fn lowerToMiEnc(tag: Tag, reg_or_mem: RegisterOrMemory, imm: i32, code: *std.Arr
}
}
} else {
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (dst_mem.rip) {
encoder.modRm_RIPDisp32(modrm_ext);
} else {
@@ -937,10 +951,7 @@ fn lowerToRmEnc(
reg_or_mem: RegisterOrMemory,
code: *std.ArrayList(u8),
) InnerError!void {
- var opc = getOpCode(tag, .rm).?;
- if (reg.size() == 8) {
- opc -= 1;
- }
+ const opc = getOpCode(tag, .rm, reg.size() == 8).?;
switch (reg_or_mem) {
.register => |src_reg| {
if (reg.size() != src_reg.size()) return error.EmitFail;
@@ -950,7 +961,7 @@ fn lowerToRmEnc(
.r = reg.isExtended(),
.b = src_reg.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
encoder.modRm_direct(reg.lowId(), src_reg.lowId());
},
.memory => |src_mem| {
@@ -967,7 +978,7 @@ fn lowerToRmEnc(
.r = reg.isExtended(),
.b = src_reg.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (src_reg.lowId() == 4) {
if (src_mem.disp == 0) {
encoder.modRm_SIBDisp0(reg.lowId());
@@ -997,7 +1008,7 @@ fn lowerToRmEnc(
.w = reg.size() == 64,
.r = reg.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (src_mem.rip) {
encoder.modRm_RIPDisp32(reg.lowId());
} else {
@@ -1022,10 +1033,7 @@ fn lowerToMrEnc(
// * reg is 32bit - dword ptr
// * reg is 16bit - word ptr
// * reg is 8bit - byte ptr
- var opc = getOpCode(tag, .mr).?;
- if (reg.size() == 8) {
- opc -= 1;
- }
+ const opc = getOpCode(tag, .mr, reg.size() == 8).?;
switch (reg_or_mem) {
.register => |dst_reg| {
if (dst_reg.size() != reg.size()) return error.EmitFail;
@@ -1035,7 +1043,7 @@ fn lowerToMrEnc(
.r = reg.isExtended(),
.b = dst_reg.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
encoder.modRm_direct(reg.lowId(), dst_reg.lowId());
},
.memory => |dst_mem| {
@@ -1050,7 +1058,7 @@ fn lowerToMrEnc(
.r = reg.isExtended(),
.b = dst_reg.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (dst_reg.lowId() == 4) {
if (dst_mem.disp == 0) {
encoder.modRm_SIBDisp0(reg.lowId());
@@ -1080,7 +1088,7 @@ fn lowerToMrEnc(
.w = reg.size() == 64,
.r = reg.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (dst_mem.rip) {
encoder.modRm_RIPDisp32(reg.lowId());
} else {
@@ -1168,10 +1176,7 @@ fn mirArithScaleSrc(emit: *Emit, tag: Tag, inst: Mir.Inst.Index) InnerError!void
const ops = Mir.Ops.decode(emit.mir.instructions.items(.ops)[inst]);
const scale = ops.flags;
// OP reg1, [reg2 + scale*rcx + imm32]
- var opc = getOpCode(tag, .rm).?;
- if (ops.reg1.size() == 8) {
- opc -= 1;
- }
+ const opc = getOpCode(tag, .rm, ops.reg1.size() == 8).?;
const imm = emit.mir.instructions.items(.data)[inst].imm;
const encoder = try Encoder.init(emit.code, 8);
encoder.rex(.{
@@ -1179,7 +1184,7 @@ fn mirArithScaleSrc(emit: *Emit, tag: Tag, inst: Mir.Inst.Index) InnerError!void
.r = ops.reg1.isExtended(),
.b = ops.reg2.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (imm <= math.maxInt(i8)) {
encoder.modRm_SIBDisp8(ops.reg1.lowId());
encoder.sib_scaleIndexBaseDisp8(scale, Register.rcx.lowId(), ops.reg2.lowId());
@@ -1198,17 +1203,14 @@ fn mirArithScaleDst(emit: *Emit, tag: Tag, inst: Mir.Inst.Index) InnerError!void
if (ops.reg2 == .none) {
// OP [reg1 + scale*rax + 0], imm32
- var opc = getOpCode(tag, .mi).?;
+ const opc = getOpCode(tag, .mi, ops.reg1.size() == 8).?;
const modrm_ext = getModRmExt(tag).?;
- if (ops.reg1.size() == 8) {
- opc -= 1;
- }
const encoder = try Encoder.init(emit.code, 8);
encoder.rex(.{
.w = ops.reg1.size() == 64,
.b = ops.reg1.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
encoder.modRm_SIBDisp0(modrm_ext);
encoder.sib_scaleIndexBase(scale, Register.rax.lowId(), ops.reg1.lowId());
if (imm <= math.maxInt(i8)) {
@@ -1222,17 +1224,14 @@ fn mirArithScaleDst(emit: *Emit, tag: Tag, inst: Mir.Inst.Index) InnerError!void
}
// OP [reg1 + scale*rax + imm32], reg2
- var opc = getOpCode(tag, .mr).?;
- if (ops.reg1.size() == 8) {
- opc -= 1;
- }
+ const opc = getOpCode(tag, .mr, ops.reg1.size() == 8).?;
const encoder = try Encoder.init(emit.code, 8);
encoder.rex(.{
.w = ops.reg1.size() == 64,
.r = ops.reg2.isExtended(),
.b = ops.reg1.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (imm <= math.maxInt(i8)) {
encoder.modRm_SIBDisp8(ops.reg2.lowId());
encoder.sib_scaleIndexBaseDisp8(scale, Register.rax.lowId(), ops.reg1.lowId());
@@ -1249,17 +1248,14 @@ fn mirArithScaleImm(emit: *Emit, tag: Tag, inst: Mir.Inst.Index) InnerError!void
const scale = ops.flags;
const payload = emit.mir.instructions.items(.data)[inst].payload;
const imm_pair = emit.mir.extraData(Mir.ImmPair, payload).data;
- var opc = getOpCode(tag, .mi).?;
- if (ops.reg1.size() == 8) {
- opc -= 1;
- }
+ const opc = getOpCode(tag, .mi, ops.reg1.size() == 8).?;
const modrm_ext = getModRmExt(tag).?;
const encoder = try Encoder.init(emit.code, 2);
encoder.rex(.{
.w = ops.reg1.size() == 64,
.b = ops.reg1.isExtended(),
});
- encoder.opcode_1byte(opc);
+ opc.encode(encoder);
if (imm_pair.dest_off <= math.maxInt(i8)) {
encoder.modRm_SIBDisp8(modrm_ext);
encoder.sib_scaleIndexBaseDisp8(scale, Register.rax.lowId(), ops.reg1.lowId());