Merge pull request #11036 from ziglang/x64-optionals

x64: handle more optional types

src/arch/x86_64/CodeGen.zig

@@ -472,10 +472,14 @@ fn gen(self: *Self) InnerError!void {
                 .regs = 0,
                 .disp = mem.alignForwardGeneric(u32, self.next_stack_offset, 8),
             };
+            var disp = data.disp + 8;
             inline for (callee_preserved_regs) |reg, i| {
                 if (self.register_manager.isRegAllocated(reg)) {
                     if (reg.to64() == .rdi) {
                         for (self.ret_backpatches.items) |inst| {
+                            log.debug(".rdi was spilled, backpatching with mov from stack at offset {}", .{
+                                -@intCast(i32, disp),
+                            });
                             const ops = Mir.Ops.decode(self.mir_instructions.items(.ops)[inst]);
                             self.mir_instructions.set(inst, Mir.Inst{
                                 .tag = .mov,
@@ -484,12 +488,13 @@ fn gen(self: *Self) InnerError!void {
                                     .reg2 = .rbp,
                                     .flags = 0b01,
                                 }).encode(),
-                                .data = .{ .imm = @bitCast(u32, -@intCast(i32, self.max_end_stack + 8)) },
+                                .data = .{ .imm = @bitCast(u32, -@intCast(i32, disp)) },
                             });
                         }
                     }
                     data.regs |= 1 << @intCast(u5, i);
                     self.max_end_stack += 8;
+                    disp += 8;
                 }
             }
             break :blk try self.addExtra(data);
@@ -981,7 +986,10 @@ fn airIntCast(self: *Self, inst: Air.Inst.Index) !void {
         operand.freezeIfRegister(&self.register_manager);
         defer operand.unfreezeIfRegister(&self.register_manager);
 
-        break :blk try self.copyToRegisterWithInstTracking(inst, dest_ty, operand);
+        const reg = try self.register_manager.allocReg(inst);
+        try self.genSetReg(dest_ty, reg, .{ .immediate = 0 });
+        try self.genSetReg(operand_ty, reg, operand);
+        break :blk MCValue{ .register = reg };
     };
 
     return self.finishAir(inst, dst_mcv, .{ ty_op.operand, .none, .none });
@@ -1704,12 +1712,36 @@ fn airShr(self: *Self, inst: Air.Inst.Index) !void {
 
 fn airOptionalPayload(self: *Self, inst: Air.Inst.Index) !void {
     const ty_op = self.air.instructions.items(.data)[inst].ty_op;
-    const result: MCValue = if (self.liveness.isUnused(inst)) .dead else result: {
+    if (self.liveness.isUnused(inst)) {
+        return self.finishAir(inst, .dead, .{ ty_op.operand, .none, .none });
+    }
+
+    const payload_ty = self.air.typeOfIndex(inst);
+    const optional_ty = self.air.typeOf(ty_op.operand);
     const operand = try self.resolveInst(ty_op.operand);
+    const result: MCValue = result: {
+        if (!payload_ty.hasRuntimeBits()) break :result MCValue.none;
+        if (optional_ty.isPtrLikeOptional()) {
             if (self.reuseOperand(inst, ty_op.operand, 0, operand)) {
                 break :result operand;
             }
-        break :result try self.copyToRegisterWithInstTracking(inst, self.air.typeOfIndex(inst), operand);
+            break :result try self.copyToRegisterWithInstTracking(inst, payload_ty, operand);
+        }
+
+        const offset = optional_ty.abiSize(self.target.*) - payload_ty.abiSize(self.target.*);
+        switch (operand) {
+            .stack_offset => |off| {
+                break :result MCValue{ .stack_offset = off - @intCast(i32, offset) };
+            },
+            .register => {
+                // TODO reuse the operand
+                const result = try self.copyToRegisterWithInstTracking(inst, optional_ty, operand);
+                const shift = @intCast(u8, offset * 8);
+                try self.shiftRegister(result.register, @intCast(u8, shift));
+                break :result result;
+            },
+            else => return self.fail("TODO implement optional_payload when operand is {}", .{operand}),
+        }
     };
     return self.finishAir(inst, result, .{ ty_op.operand, .none, .none });
 }
@@ -1827,14 +1859,38 @@ fn airErrUnionPayloadPtrSet(self: *Self, inst: Air.Inst.Index) !void {
 
 fn airWrapOptional(self: *Self, inst: Air.Inst.Index) !void {
     const ty_op = self.air.instructions.items(.data)[inst].ty_op;
-    const result: MCValue = if (self.liveness.isUnused(inst)) .dead else result: {
+    if (self.liveness.isUnused(inst)) {
-        const optional_ty = self.air.typeOfIndex(inst);
+        return self.finishAir(inst, .dead, .{ ty_op.operand, .none, .none });
+    }
 
-        // Optional with a zero-bit payload type is just a boolean true
+    const payload_ty = self.air.typeOf(ty_op.operand);
-        if (optional_ty.abiSize(self.target.*) == 1)
+    const result: MCValue = result: {
+        if (!payload_ty.hasRuntimeBits()) {
             break :result MCValue{ .immediate = 1 };
+        }
 
-        return self.fail("TODO implement wrap optional for {}", .{self.target.cpu.arch});
+        const optional_ty = self.air.typeOfIndex(inst);
+        const operand = try self.resolveInst(ty_op.operand);
+        operand.freezeIfRegister(&self.register_manager);
+        defer operand.unfreezeIfRegister(&self.register_manager);
+
+        if (optional_ty.isPtrLikeOptional()) {
+            // TODO should we check if we can reuse the operand?
+            if (self.reuseOperand(inst, ty_op.operand, 0, operand)) {
+                break :result operand;
+            }
+            break :result try self.copyToRegisterWithInstTracking(inst, payload_ty, operand);
+        }
+
+        const optional_abi_size = @intCast(u32, optional_ty.abiSize(self.target.*));
+        const optional_abi_align = optional_ty.abiAlignment(self.target.*);
+        const payload_abi_size = @intCast(u32, payload_ty.abiSize(self.target.*));
+        const offset = optional_abi_size - payload_abi_size;
+
+        const stack_offset = @intCast(i32, try self.allocMem(inst, optional_abi_size, optional_abi_align));
+        try self.genSetStack(Type.bool, stack_offset, .{ .immediate = 1 }, .{});
+        try self.genSetStack(payload_ty, stack_offset - @intCast(i32, offset), operand, .{});
+        break :result MCValue{ .stack_offset = stack_offset };
     };
     return self.finishAir(inst, result, .{ ty_op.operand, .none, .none });
 }
@@ -3761,7 +3817,14 @@ fn isNull(self: *Self, inst: Air.Inst.Index, ty: Type, operand: MCValue) !MCValu
     try self.spillCompareFlagsIfOccupied();
     self.compare_flags_inst = inst;
 
-    try self.genBinMathOpMir(.cmp, ty, operand, MCValue{ .immediate = 0 });
+    const cmp_ty: Type = if (!ty.isPtrLikeOptional()) blk: {
+        var buf: Type.Payload.ElemType = undefined;
+        const payload_ty = ty.optionalChild(&buf);
+        break :blk if (payload_ty.hasRuntimeBits()) Type.bool else ty;
+    } else ty;
+
+    try self.genBinMathOpMir(.cmp, cmp_ty, operand, MCValue{ .immediate = 0 });
+
     return MCValue{ .compare_flags_unsigned = .eq };
 }
 
@@ -5625,7 +5688,7 @@ fn genTypedValue(self: *Self, typed_value: TypedValue) InnerError!MCValue {
                     .val = typed_value.val,
                 });
             } else if (typed_value.ty.abiSize(self.target.*) == 1) {
-                return MCValue{ .immediate = @boolToInt(typed_value.val.isNull()) };
+                return MCValue{ .immediate = @boolToInt(!typed_value.val.isNull()) };
             }
         },
         .Enum => {

src/codegen.zig

@@ -140,6 +140,16 @@ pub fn generateFunction(
     }
 }
 
+fn writeFloat(comptime F: type, f: F, target: Target, endian: std.builtin.Endian, code: []u8) void {
+    _ = target;
+    const Int = @Type(.{ .Int = .{
+        .signedness = .unsigned,
+        .bits = @typeInfo(F).Float.bits,
+    } });
+    const int = @bitCast(Int, f);
+    mem.writeInt(Int, code[0..@sizeOf(Int)], int, endian);
+}
+
 pub fn generateSymbol(
     bin_file: *link.File,
     src_loc: Module.SrcLoc,
@@ -151,10 +161,12 @@ pub fn generateSymbol(
     const tracy = trace(@src());
     defer tracy.end();
 
+    const target = bin_file.options.target;
+    const endian = target.cpu.arch.endian();
+
     log.debug("generateSymbol: ty = {}, val = {}", .{ typed_value.ty, typed_value.val });
 
     if (typed_value.val.isUndefDeep()) {
-        const target = bin_file.options.target;
         const abi_size = try math.cast(usize, typed_value.ty.abiSize(target));
         try code.appendNTimes(0xaa, abi_size);
         return Result{ .appended = {} };
@@ -171,6 +183,25 @@ pub fn generateSymbol(
                 ),
             };
         },
+        .Float => {
+            const float_bits = typed_value.ty.floatBits(target);
+            switch (float_bits) {
+                16 => writeFloat(f16, typed_value.val.toFloat(f16), target, endian, try code.addManyAsArray(2)),
+                32 => writeFloat(f32, typed_value.val.toFloat(f32), target, endian, try code.addManyAsArray(4)),
+                64 => writeFloat(f64, typed_value.val.toFloat(f64), target, endian, try code.addManyAsArray(8)),
+                80 => return Result{
+                    .fail = try ErrorMsg.create(
+                        bin_file.allocator,
+                        src_loc,
+                        "TODO handle f80 in generateSymbol",
+                        .{},
+                    ),
+                },
+                128 => writeFloat(f128, typed_value.val.toFloat(f128), target, endian, try code.addManyAsArray(16)),
+                else => unreachable,
+            }
+            return Result{ .appended = {} };
+        },
         .Array => switch (typed_value.val.tag()) {
             .bytes => {
                 // TODO populate .debug_info for the array
@@ -311,7 +342,6 @@ pub fn generateSymbol(
                 return Result{ .appended = {} };
             },
             .field_ptr => {
-                const target = bin_file.options.target;
                 const field_ptr = typed_value.val.castTag(.field_ptr).?.data;
                 const container_ptr = field_ptr.container_ptr;
 
@@ -373,7 +403,6 @@ pub fn generateSymbol(
         },
         .Int => {
             // TODO populate .debug_info for the integer
-            const endian = bin_file.options.target.cpu.arch.endian();
             const info = typed_value.ty.intInfo(bin_file.options.target);
             if (info.bits <= 8) {
                 const x = @intCast(u8, typed_value.val.toUnsignedInt());
@@ -423,7 +452,6 @@ pub fn generateSymbol(
             var int_buffer: Value.Payload.U64 = undefined;
             const int_val = typed_value.enumToInt(&int_buffer);
 
-            const target = bin_file.options.target;
             const info = typed_value.ty.intInfo(target);
             if (info.bits <= 8) {
                 const x = @intCast(u8, int_val.toUnsignedInt());
@@ -440,7 +468,6 @@ pub fn generateSymbol(
                     ),
                 };
             }
-            const endian = target.cpu.arch.endian();
             switch (info.signedness) {
                 .unsigned => {
                     if (info.bits <= 16) {
@@ -506,7 +533,6 @@ pub fn generateSymbol(
                 const unpadded_field_end = code.items.len - struct_begin;
 
                 // Pad struct members if required
-                const target = bin_file.options.target;
                 const padded_field_end = typed_value.ty.structFieldOffset(index + 1, target);
                 const padding = try math.cast(usize, padded_field_end - unpadded_field_end);
 
@@ -519,7 +545,6 @@ pub fn generateSymbol(
         },
         .Union => {
             // TODO generate debug info for unions
-            const target = bin_file.options.target;
             const union_obj = typed_value.val.castTag(.@"union").?.data;
             const layout = typed_value.ty.unionGetLayout(target);
 
@@ -590,19 +615,69 @@ pub fn generateSymbol(
             return Result{ .appended = {} };
         },
         .Optional => {
-            // TODO generateSymbol for optionals
+            // TODO generate debug info for optionals
-            const target = bin_file.options.target;
+            var opt_buf: Type.Payload.ElemType = undefined;
+            const payload_type = typed_value.ty.optionalChild(&opt_buf);
+            const is_pl = !typed_value.val.isNull();
             const abi_size = try math.cast(usize, typed_value.ty.abiSize(target));
-            try code.writer().writeByteNTimes(0xaa, abi_size);
+            const offset = abi_size - try math.cast(usize, payload_type.abiSize(target));
+
+            if (!payload_type.hasRuntimeBits()) {
+                try code.writer().writeByteNTimes(@boolToInt(is_pl), abi_size);
+                return Result{ .appended = {} };
+            }
+
+            if (typed_value.ty.isPtrLikeOptional()) {
+                if (typed_value.val.castTag(.opt_payload)) |payload| {
+                    switch (try generateSymbol(bin_file, src_loc, .{
+                        .ty = payload_type,
+                        .val = payload.data,
+                    }, code, debug_output, reloc_info)) {
+                        .appended => {},
+                        .externally_managed => |external_slice| {
+                            code.appendSliceAssumeCapacity(external_slice);
+                        },
+                        .fail => |em| return Result{ .fail = em },
+                    }
+                } else if (!typed_value.val.isNull()) {
+                    switch (try generateSymbol(bin_file, src_loc, .{
+                        .ty = payload_type,
+                        .val = typed_value.val,
+                    }, code, debug_output, reloc_info)) {
+                        .appended => {},
+                        .externally_managed => |external_slice| {
+                            code.appendSliceAssumeCapacity(external_slice);
+                        },
+                        .fail => |em| return Result{ .fail = em },
+                    }
+                } else {
+                    try code.writer().writeByteNTimes(0, abi_size);
+                }
+
+                return Result{ .appended = {} };
+            }
+
+            const value = if (typed_value.val.castTag(.opt_payload)) |payload| payload.data else Value.initTag(.undef);
+            try code.writer().writeByteNTimes(@boolToInt(is_pl), offset);
+            switch (try generateSymbol(bin_file, src_loc, .{
+                .ty = payload_type,
+                .val = value,
+            }, code, debug_output, reloc_info)) {
+                .appended => {},
+                .externally_managed => |external_slice| {
+                    code.appendSliceAssumeCapacity(external_slice);
+                },
+                .fail => |em| return Result{ .fail = em },
+            }
 
             return Result{ .appended = {} };
         },
         .ErrorUnion => {
+            // TODO generate debug info for error unions
             const error_ty = typed_value.ty.errorUnionSet();
             const payload_ty = typed_value.ty.errorUnionPayload();
             const is_payload = typed_value.val.errorUnionIsPayload();
 
-            const target = bin_file.options.target;
             const abi_align = typed_value.ty.abiAlignment(target);
 
             const error_val = if (!is_payload) typed_value.val else Value.initTag(.zero);
@@ -643,12 +718,11 @@ pub fn generateSymbol(
             return Result{ .appended = {} };
         },
         .ErrorSet => {
-            const target = bin_file.options.target;
+            // TODO generate debug info for error sets
             switch (typed_value.val.tag()) {
                 .@"error" => {
                     const name = typed_value.val.getError().?;
                     const kv = try bin_file.options.module.?.getErrorValue(name);
-                    const endian = target.cpu.arch.endian();
                     try code.writer().writeInt(u32, kv.value, endian);
                 },
                 else => {

test/behavior/basic.zig

@@ -728,7 +728,6 @@ test "thread local variable" {
 test "result location is optional inside error union" {
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
 

test/behavior/bugs/2889.zig

@@ -27,7 +27,6 @@ fn parseNote() ?i32 {
 }
 
 test "fixed" {
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
 

test/behavior/bugs/3112.zig

@@ -16,7 +16,6 @@ test "zig test crash" {
     if (builtin.zig_backend == .stage1) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest;
     var global: State = undefined;
     global.enter = prev;
     global.enter(null);

test/behavior/cast.zig

@@ -19,7 +19,7 @@ test "integer literal to pointer cast" {
 
 test "peer type resolution: ?T and T" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
-    if (builtin.zig_backend == .stage2_x86_64 or builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
 
     try expect(peerTypeTAndOptionalT(true, false).? == 0);
     try expect(peerTypeTAndOptionalT(false, false).? == 3);
@@ -179,7 +179,7 @@ test "@floatCast comptime_int and comptime_float" {
 
 test "coerce undefined to optional" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
-    if (builtin.zig_backend == .stage2_x86_64 or builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
 
     try expect(MakeType(void).getNull() == null);
     try expect(MakeType(void).getNonNull() != null);
@@ -237,7 +237,7 @@ test "@intCast to u0 and use the result" {
 
 test "peer result null and comptime_int" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
-    if (builtin.zig_backend == .stage2_x86_64 or builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
 
     const S = struct {
         fn blah(n: i32) ?i32 {
@@ -302,7 +302,7 @@ fn implicitIntLitToOptional() void {
 
 test "return u8 coercing into ?u32 return type" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
-    if (builtin.zig_backend == .stage2_x86_64 or builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
 
     const S = struct {
         fn doTheTest() !void {
@@ -373,7 +373,6 @@ fn testPeerResolveArrayConstSlice(b: bool) !void {
 test "implicitly cast from T to anyerror!?T" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest;
 
     try castToOptionalTypeError(1);
     comptime try castToOptionalTypeError(1);
@@ -1036,7 +1035,6 @@ test "implicit cast from [*]T to ?*anyopaque" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     var a = [_]u8{ 3, 2, 1 };
     var runtime_zero: usize = 0;
@@ -1073,7 +1071,6 @@ test "implicit ptr to *anyopaque" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     var a: u32 = 1;
     var ptr: *align(@alignOf(u32)) anyopaque = &a;
@@ -1087,7 +1084,6 @@ test "implicit ptr to *anyopaque" {
 test "return null from fn() anyerror!?&T" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     const a = returnNullFromOptionalTypeErrorRef();
     const b = returnNullLitFromOptionalTypeErrorRef();
@@ -1125,7 +1121,6 @@ test "implicitly cast from [N]T to ?[]const T" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     try expect(mem.eql(u8, castToOptionalSlice().?, "hi"));
     comptime try expect(mem.eql(u8, castToOptionalSlice().?, "hi"));
@@ -1177,7 +1172,6 @@ test "implicit cast from *T to ?*anyopaque" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     var a: u8 = 1;
     incrementVoidPtrValue(&a);
@@ -1213,7 +1207,6 @@ test "*const [N]null u8 to ?[]const u8" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     const S = struct {
         fn doTheTest() !void {
@@ -1249,7 +1242,6 @@ test "assignment to optional pointer result loc" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     var foo: struct { ptr: ?*anyopaque } = .{ .ptr = &global_struct };
     try expect(foo.ptr.? == @ptrCast(*anyopaque, &global_struct));

test/behavior/enum.zig

@@ -1083,7 +1083,6 @@ test "@tagName on enum literals" {
 }
 
 test "enum literal casting to optional" {
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
 

test/behavior/optional.zig

@@ -7,7 +7,6 @@ const expectEqual = testing.expectEqual;
 test "passing an optional integer as a parameter" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     const S = struct {
         fn entry() bool {
@@ -60,7 +59,6 @@ fn testNullPtrsEql() !void {
 test "optional with void type" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     const Foo = struct {
         x: ?void,
@@ -171,7 +169,6 @@ test "unwrap function call with optional pointer return value" {
 test "nested orelse" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     const S = struct {
         fn entry() !void {
@@ -199,7 +196,6 @@ test "self-referential struct through a slice of optional" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
 
     const S = struct {
         const Node = struct {