compiler: split Decl into Nav and Cau

The type `Zcu.Decl` in the compiler is problematic: over time it has
gained many responsibilities. Every source declaration, container type,
generic instantiation, and `@extern` has a `Decl`. The functions of
these `Decl`s are in some cases entirely disjoint.

After careful analysis, I determined that the two main responsibilities
of `Decl` are as follows:
* A `Decl` acts as the "subject" of semantic analysis at comptime. A
  single unit of analysis is either a runtime function body, or a
  `Decl`. It registers incremental dependencies, tracks analysis errors,
  etc.
* A `Decl` acts as a "global variable": a pointer to it is consistent,
  and it may be lowered to a specific symbol by the codegen backend.

This commit eliminates `Decl` and introduces new types to model these
responsibilities: `Cau` (Comptime Analysis Unit) and `Nav` (Named
Addressable Value).

Every source declaration, and every container type requiring resolution
(so *not* including `opaque`), has a `Cau`. For a source declaration,
this `Cau` performs the resolution of its value. (When #131 is
implemented, it is unsolved whether type and value resolution will share
a `Cau` or have two distinct `Cau`s.) For a type, this `Cau` is the
context in which type resolution occurs.

Every non-`comptime` source declaration, every generic instantiation,
and every distinct `extern` has a `Nav`. These are sent to codegen/link:
the backends by definition do not care about `Cau`s.

This commit has some minor technically-breaking changes surrounding
`usingnamespace`. I don't think they'll impact anyone, since the changes
are fixes around semantics which were previously inconsistent (the
behavior changed depending on hashmap iteration order!).

Aside from that, this changeset has no significant user-facing changes.
Instead, it is an internal refactor which makes it easier to correctly
model the responsibilities of different objects, particularly regarding
incremental compilation. The performance impact should be negligible,
but I will take measurements before merging this work into `master`.

Co-authored-by: Jacob Young <jacobly0@users.noreply.github.com>
Co-authored-by: Jakub Konka <kubkon@jakubkonka.com>

1 files changed, 84 insertions, 109 deletions

diff --git a/src/arch/x86_64/CodeGen.zig b/src/arch/x86_64/CodeGen.zig
index 924de9d25a..a36bd981bc 100644
--- a/src/arch/x86_64/CodeGen.zig
+++ b/src/arch/x86_64/CodeGen.zig
@@ -116,48 +116,36 @@ const RegisterOffset = struct { reg: Register, off: i32 = 0 };
 const SymbolOffset = struct { sym: u32, off: i32 = 0 };
 
 const Owner = union(enum) {
-    func_index: InternPool.Index,
+    nav_index: InternPool.Nav.Index,
     lazy_sym: link.File.LazySymbol,
 
-    fn getDecl(owner: Owner, zcu: *Zcu) InternPool.DeclIndex {
-        return switch (owner) {
-            .func_index => |func_index| zcu.funcOwnerDeclIndex(func_index),
-            .lazy_sym => |lazy_sym| lazy_sym.ty.getOwnerDecl(zcu),
-        };
-    }
-
     fn getSymbolIndex(owner: Owner, ctx: *Self) !u32 {
         const pt = ctx.pt;
         switch (owner) {
-            .func_index => |func_index| {
-                const decl_index = ctx.pt.zcu.funcOwnerDeclIndex(func_index);
-                if (ctx.bin_file.cast(link.File.Elf)) |elf_file| {
-                    return elf_file.zigObjectPtr().?.getOrCreateMetadataForDecl(elf_file, decl_index);
-                } else if (ctx.bin_file.cast(link.File.MachO)) |macho_file| {
-                    return macho_file.getZigObject().?.getOrCreateMetadataForDecl(macho_file, decl_index);
-                } else if (ctx.bin_file.cast(link.File.Coff)) |coff_file| {
-                    const atom = try coff_file.getOrCreateAtomForDecl(decl_index);
-                    return coff_file.getAtom(atom).getSymbolIndex().?;
-                } else if (ctx.bin_file.cast(link.File.Plan9)) |p9_file| {
-                    return p9_file.seeDecl(decl_index);
-                } else unreachable;
-            },
-            .lazy_sym => |lazy_sym| {
-                if (ctx.bin_file.cast(link.File.Elf)) |elf_file| {
-                    return elf_file.zigObjectPtr().?.getOrCreateMetadataForLazySymbol(elf_file, pt, lazy_sym) catch |err|
-                        ctx.fail("{s} creating lazy symbol", .{@errorName(err)});
-                } else if (ctx.bin_file.cast(link.File.MachO)) |macho_file| {
-                    return macho_file.getZigObject().?.getOrCreateMetadataForLazySymbol(macho_file, pt, lazy_sym) catch |err|
-                        ctx.fail("{s} creating lazy symbol", .{@errorName(err)});
-                } else if (ctx.bin_file.cast(link.File.Coff)) |coff_file| {
-                    const atom = coff_file.getOrCreateAtomForLazySymbol(pt, lazy_sym) catch |err|
-                        return ctx.fail("{s} creating lazy symbol", .{@errorName(err)});
-                    return coff_file.getAtom(atom).getSymbolIndex().?;
-                } else if (ctx.bin_file.cast(link.File.Plan9)) |p9_file| {
-                    return p9_file.getOrCreateAtomForLazySymbol(pt, lazy_sym) catch |err|
-                        return ctx.fail("{s} creating lazy symbol", .{@errorName(err)});
-                } else unreachable;
-            },
+            .nav_index => |nav_index| if (ctx.bin_file.cast(.elf)) |elf_file| {
+                return elf_file.zigObjectPtr().?.getOrCreateMetadataForNav(elf_file, nav_index);
+            } else if (ctx.bin_file.cast(.macho)) |macho_file| {
+                return macho_file.getZigObject().?.getOrCreateMetadataForNav(macho_file, nav_index);
+            } else if (ctx.bin_file.cast(.coff)) |coff_file| {
+                const atom = try coff_file.getOrCreateAtomForNav(nav_index);
+                return coff_file.getAtom(atom).getSymbolIndex().?;
+            } else if (ctx.bin_file.cast(.plan9)) |p9_file| {
+                return p9_file.seeNav(pt, nav_index);
+            } else unreachable,
+            .lazy_sym => |lazy_sym| if (ctx.bin_file.cast(.elf)) |elf_file| {
+                return elf_file.zigObjectPtr().?.getOrCreateMetadataForLazySymbol(elf_file, pt, lazy_sym) catch |err|
+                    ctx.fail("{s} creating lazy symbol", .{@errorName(err)});
+            } else if (ctx.bin_file.cast(.macho)) |macho_file| {
+                return macho_file.getZigObject().?.getOrCreateMetadataForLazySymbol(macho_file, pt, lazy_sym) catch |err|
+                    ctx.fail("{s} creating lazy symbol", .{@errorName(err)});
+            } else if (ctx.bin_file.cast(.coff)) |coff_file| {
+                const atom = coff_file.getOrCreateAtomForLazySymbol(pt, lazy_sym) catch |err|
+                    return ctx.fail("{s} creating lazy symbol", .{@errorName(err)});
+                return coff_file.getAtom(atom).getSymbolIndex().?;
+            } else if (ctx.bin_file.cast(.plan9)) |p9_file| {
+                return p9_file.getOrCreateAtomForLazySymbol(pt, lazy_sym) catch |err|
+                    return ctx.fail("{s} creating lazy symbol", .{@errorName(err)});
+            } else unreachable,
         }
     }
 };
@@ -803,14 +791,12 @@ pub fn generate(
     debug_output: DebugInfoOutput,
 ) CodeGenError!Result {
     const zcu = pt.zcu;
-    const gpa = zcu.gpa;
     const comp = zcu.comp;
+    const gpa = zcu.gpa;
+    const ip = &zcu.intern_pool;
     const func = zcu.funcInfo(func_index);
-    const fn_owner_decl = zcu.declPtr(func.owner_decl);
-    assert(fn_owner_decl.has_tv);
-    const fn_type = fn_owner_decl.typeOf(zcu);
-    const namespace = zcu.namespacePtr(fn_owner_decl.src_namespace);
-    const mod = namespace.fileScope(zcu).mod;
+    const fn_type = Type.fromInterned(func.ty);
+    const mod = zcu.navFileScope(func.owner_nav).mod;
 
     var function: Self = .{
         .gpa = gpa,
@@ -821,7 +807,7 @@ pub fn generate(
         .mod = mod,
         .bin_file = bin_file,
         .debug_output = debug_output,
-        .owner = .{ .func_index = func_index },
+        .owner = .{ .nav_index = func.owner_nav },
         .inline_func = func_index,
         .err_msg = null,
         .args = undefined, // populated after `resolveCallingConventionValues`
@@ -847,9 +833,7 @@ pub fn generate(
         function.mir_extra.deinit(gpa);
     }
 
-    wip_mir_log.debug("{}:", .{function.fmtDecl(func.owner_decl)});
-
-    const ip = &zcu.intern_pool;
+    wip_mir_log.debug("{}:", .{fmtNav(func.owner_nav, ip)});
 
     try function.frame_allocs.resize(gpa, FrameIndex.named_count);
     function.frame_allocs.set(
@@ -1067,22 +1051,22 @@ pub fn generateLazy(
     }
 }
 
-const FormatDeclData = struct {
-    zcu: *Zcu,
-    decl_index: InternPool.DeclIndex,
+const FormatNavData = struct {
+    ip: *const InternPool,
+    nav_index: InternPool.Nav.Index,
 };
-fn formatDecl(
-    data: FormatDeclData,
+fn formatNav(
+    data: FormatNavData,
     comptime _: []const u8,
     _: std.fmt.FormatOptions,
     writer: anytype,
 ) @TypeOf(writer).Error!void {
-    try writer.print("{}", .{data.zcu.declPtr(data.decl_index).fqn.fmt(&data.zcu.intern_pool)});
+    try writer.print("{}", .{data.ip.getNav(data.nav_index).fqn.fmt(data.ip)});
 }
-fn fmtDecl(self: *Self, decl_index: InternPool.DeclIndex) std.fmt.Formatter(formatDecl) {
+fn fmtNav(nav_index: InternPool.Nav.Index, ip: *const InternPool) std.fmt.Formatter(formatNav) {
     return .{ .data = .{
-        .zcu = self.pt.zcu,
-        .decl_index = decl_index,
+        .ip = ip,
+        .nav_index = nav_index,
     } };
 }
 
@@ -2230,9 +2214,9 @@ fn genLazy(self: *Self, lazy_sym: link.File.LazySymbol) InnerError!void {
     const pt = self.pt;
     const mod = pt.zcu;
     const ip = &mod.intern_pool;
-    switch (lazy_sym.ty.zigTypeTag(mod)) {
+    switch (Type.fromInterned(lazy_sym.ty).zigTypeTag(mod)) {
         .Enum => {
-            const enum_ty = lazy_sym.ty;
+            const enum_ty = Type.fromInterned(lazy_sym.ty);
             wip_mir_log.debug("{}.@tagName:", .{enum_ty.fmt(pt)});
 
             const resolved_cc = abi.resolveCallingConvention(.Unspecified, self.target.*);
@@ -2249,7 +2233,7 @@ fn genLazy(self: *Self, lazy_sym: link.File.LazySymbol) InnerError!void {
             const data_reg = try self.register_manager.allocReg(null, abi.RegisterClass.gp);
             const data_lock = self.register_manager.lockRegAssumeUnused(data_reg);
             defer self.register_manager.unlockReg(data_lock);
-            try self.genLazySymbolRef(.lea, data_reg, .{ .kind = .const_data, .ty = enum_ty });
+            try self.genLazySymbolRef(.lea, data_reg, .{ .kind = .const_data, .ty = enum_ty.toIntern() });
 
             var data_off: i32 = 0;
             const tag_names = enum_ty.enumFields(mod);
@@ -2288,7 +2272,7 @@ fn genLazy(self: *Self, lazy_sym: link.File.LazySymbol) InnerError!void {
         },
         else => return self.fail(
             "TODO implement {s} for {}",
-            .{ @tagName(lazy_sym.kind), lazy_sym.ty.fmt(pt) },
+            .{ @tagName(lazy_sym.kind), Type.fromInterned(lazy_sym.ty).fmt(pt) },
         ),
     }
 }
@@ -11932,11 +11916,9 @@ fn airArg(self: *Self, inst: Air.Inst.Index) !void {
 }
 
 fn genArgDbgInfo(self: Self, ty: Type, name: [:0]const u8, mcv: MCValue) !void {
-    const pt = self.pt;
-    const mod = pt.zcu;
     switch (self.debug_output) {
         .dwarf => |dw| {
-            const loc: link.File.Dwarf.DeclState.DbgInfoLoc = switch (mcv) {
+            const loc: link.File.Dwarf.NavState.DbgInfoLoc = switch (mcv) {
                 .register => |reg| .{ .register = reg.dwarfNum() },
                 .register_pair => |regs| .{ .register_pair = .{
                     regs[0].dwarfNum(), regs[1].dwarfNum(),
@@ -11955,7 +11937,7 @@ fn genArgDbgInfo(self: Self, ty: Type, name: [:0]const u8, mcv: MCValue) !void {
             // TODO: this might need adjusting like the linkers do.
             // Instead of flattening the owner and passing Decl.Index here we may
             // want to special case LazySymbol in DWARF linker too.
-            try dw.genArgDbgInfo(name, ty, self.owner.getDecl(mod), loc);
+            try dw.genArgDbgInfo(name, ty, self.owner.nav_index, loc);
         },
         .plan9 => {},
         .none => {},
@@ -11969,8 +11951,6 @@ fn genVarDbgInfo(
     mcv: MCValue,
     name: [:0]const u8,
 ) !void {
-    const pt = self.pt;
-    const mod = pt.zcu;
     const is_ptr = switch (tag) {
         .dbg_var_ptr => true,
         .dbg_var_val => false,
@@ -11979,7 +11959,7 @@ fn genVarDbgInfo(
 
     switch (self.debug_output) {
         .dwarf => |dw| {
-            const loc: link.File.Dwarf.DeclState.DbgInfoLoc = switch (mcv) {
+            const loc: link.File.Dwarf.NavState.DbgInfoLoc = switch (mcv) {
                 .register => |reg| .{ .register = reg.dwarfNum() },
                 // TODO use a frame index
                 .load_frame, .lea_frame => return,
@@ -12007,7 +11987,7 @@ fn genVarDbgInfo(
             // TODO: this might need adjusting like the linkers do.
             // Instead of flattening the owner and passing Decl.Index here we may
             // want to special case LazySymbol in DWARF linker too.
-            try dw.genVarDbgInfo(name, ty, self.owner.getDecl(mod), is_ptr, loc);
+            try dw.genVarDbgInfo(name, ty, self.owner.nav_index, is_ptr, loc);
         },
         .plan9 => {},
         .none => {},
@@ -12090,14 +12070,15 @@ fn genCall(self: *Self, info: union(enum) {
     },
 }, arg_types: []const Type, args: []const MCValue) !MCValue {
     const pt = self.pt;
-    const mod = pt.zcu;
+    const zcu = pt.zcu;
+    const ip = &zcu.intern_pool;
 
     const fn_ty = switch (info) {
         .air => |callee| fn_info: {
             const callee_ty = self.typeOf(callee);
-            break :fn_info switch (callee_ty.zigTypeTag(mod)) {
+            break :fn_info switch (callee_ty.zigTypeTag(zcu)) {
                 .Fn => callee_ty,
-                .Pointer => callee_ty.childType(mod),
+                .Pointer => callee_ty.childType(zcu),
                 else => unreachable,
             };
         },
@@ -12107,7 +12088,7 @@ fn genCall(self: *Self, info: union(enum) {
             .cc = .C,
         }),
     };
-    const fn_info = mod.typeToFunc(fn_ty).?;
+    const fn_info = zcu.typeToFunc(fn_ty).?;
     const resolved_cc = abi.resolveCallingConvention(fn_info.cc, self.target.*);
 
     const ExpectedContents = extern struct {
@@ -12225,7 +12206,7 @@ fn genCall(self: *Self, info: union(enum) {
                 try self.asmRegisterImmediate(
                     .{ ._, .cmp },
                     index_reg.to32(),
-                    Immediate.u(arg_ty.vectorLen(mod)),
+                    Immediate.u(arg_ty.vectorLen(zcu)),
                 );
                 _ = try self.asmJccReloc(.b, loop);
 
@@ -12317,18 +12298,18 @@ fn genCall(self: *Self, info: union(enum) {
     // on linking.
     switch (info) {
         .air => |callee| if (try self.air.value(callee, pt)) |func_value| {
-            const func_key = mod.intern_pool.indexToKey(func_value.ip_index);
+            const func_key = ip.indexToKey(func_value.ip_index);
             switch (switch (func_key) {
                 else => func_key,
                 .ptr => |ptr| if (ptr.byte_offset == 0) switch (ptr.base_addr) {
-                    .decl => |decl| mod.intern_pool.indexToKey(mod.declPtr(decl).val.toIntern()),
+                    .nav => |nav| ip.indexToKey(zcu.navValue(nav).toIntern()),
                     else => func_key,
                 } else func_key,
             }) {
                 .func => |func| {
-                    if (self.bin_file.cast(link.File.Elf)) |elf_file| {
+                    if (self.bin_file.cast(.elf)) |elf_file| {
                         const zo = elf_file.zigObjectPtr().?;
-                        const sym_index = try zo.getOrCreateMetadataForDecl(elf_file, func.owner_decl);
+                        const sym_index = try zo.getOrCreateMetadataForNav(elf_file, func.owner_nav);
                         if (self.mod.pic) {
                             const callee_reg: Register = switch (resolved_cc) {
                                 .SysV => callee: {
@@ -12356,14 +12337,14 @@ fn genCall(self: *Self, info: union(enum) {
                             } },
                             .mod = .{ .rm = .{ .size = .qword } },
                         });
-                    } else if (self.bin_file.cast(link.File.Coff)) |coff_file| {
-                        const atom = try coff_file.getOrCreateAtomForDecl(func.owner_decl);
+                    } else if (self.bin_file.cast(.coff)) |coff_file| {
+                        const atom = try coff_file.getOrCreateAtomForNav(func.owner_nav);
                         const sym_index = coff_file.getAtom(atom).getSymbolIndex().?;
                         try self.genSetReg(.rax, Type.usize, .{ .lea_got = sym_index }, .{});
                         try self.asmRegister(.{ ._, .call }, .rax);
-                    } else if (self.bin_file.cast(link.File.MachO)) |macho_file| {
+                    } else if (self.bin_file.cast(.macho)) |macho_file| {
                         const zo = macho_file.getZigObject().?;
-                        const sym_index = try zo.getOrCreateMetadataForDecl(macho_file, func.owner_decl);
+                        const sym_index = try zo.getOrCreateMetadataForNav(macho_file, func.owner_nav);
                         const sym = zo.symbols.items[sym_index];
                         try self.genSetReg(
                             .rax,
@@ -12372,8 +12353,8 @@ fn genCall(self: *Self, info: union(enum) {
                             .{},
                         );
                         try self.asmRegister(.{ ._, .call }, .rax);
-                    } else if (self.bin_file.cast(link.File.Plan9)) |p9| {
-                        const atom_index = try p9.seeDecl(func.owner_decl);
+                    } else if (self.bin_file.cast(.plan9)) |p9| {
+                        const atom_index = try p9.seeNav(pt, func.owner_nav);
                         const atom = p9.getAtom(atom_index);
                         try self.asmMemory(.{ ._, .call }, .{
                             .base = .{ .reg = .ds },
@@ -12384,16 +12365,15 @@ fn genCall(self: *Self, info: union(enum) {
                         });
                     } else unreachable;
                 },
-                .extern_func => |extern_func| {
-                    const owner_decl = mod.declPtr(extern_func.decl);
-                    const lib_name = extern_func.lib_name.toSlice(&mod.intern_pool);
-                    const decl_name = owner_decl.name.toSlice(&mod.intern_pool);
-                    try self.genExternSymbolRef(.call, lib_name, decl_name);
-                },
+                .@"extern" => |@"extern"| try self.genExternSymbolRef(
+                    .call,
+                    @"extern".lib_name.toSlice(ip),
+                    @"extern".name.toSlice(ip),
+                ),
                 else => return self.fail("TODO implement calling bitcasted functions", .{}),
             }
         } else {
-            assert(self.typeOf(callee).zigTypeTag(mod) == .Pointer);
+            assert(self.typeOf(callee).zigTypeTag(zcu) == .Pointer);
             try self.genSetReg(.rax, Type.usize, .{ .air_ref = callee }, .{});
             try self.asmRegister(.{ ._, .call }, .rax);
         },
@@ -12919,13 +12899,13 @@ fn airCmpVector(self: *Self, inst: Air.Inst.Index) !void {
 
 fn airCmpLtErrorsLen(self: *Self, inst: Air.Inst.Index) !void {
     const pt = self.pt;
-    const mod = pt.zcu;
     const un_op = self.air.instructions.items(.data)[@intFromEnum(inst)].un_op;
 
     const addr_reg = try self.register_manager.allocReg(null, abi.RegisterClass.gp);
     const addr_lock = self.register_manager.lockRegAssumeUnused(addr_reg);
     defer self.register_manager.unlockReg(addr_lock);
-    try self.genLazySymbolRef(.lea, addr_reg, link.File.LazySymbol.initDecl(.const_data, null, mod));
+    const anyerror_lazy_sym: link.File.LazySymbol = .{ .kind = .const_data, .ty = .anyerror_type };
+    try self.genLazySymbolRef(.lea, addr_reg, anyerror_lazy_sym);
 
     try self.spillEflagsIfOccupied();
 
@@ -15273,7 +15253,7 @@ fn genExternSymbolRef(
     callee: []const u8,
 ) InnerError!void {
     const atom_index = try self.owner.getSymbolIndex(self);
-    if (self.bin_file.cast(link.File.Elf)) |elf_file| {
+    if (self.bin_file.cast(.elf)) |elf_file| {
         _ = try self.addInst(.{
             .tag = tag,
             .ops = .extern_fn_reloc,
@@ -15282,7 +15262,7 @@ fn genExternSymbolRef(
                 .sym_index = try elf_file.getGlobalSymbol(callee, lib),
             } },
         });
-    } else if (self.bin_file.cast(link.File.Coff)) |coff_file| {
+    } else if (self.bin_file.cast(.coff)) |coff_file| {
         const global_index = try coff_file.getGlobalSymbol(callee, lib);
         _ = try self.addInst(.{
             .tag = .mov,
@@ -15300,7 +15280,7 @@ fn genExternSymbolRef(
             .call => try self.asmRegister(.{ ._, .call }, .rax),
             else => unreachable,
         }
-    } else if (self.bin_file.cast(link.File.MachO)) |macho_file| {
+    } else if (self.bin_file.cast(.macho)) |macho_file| {
         _ = try self.addInst(.{
             .tag = .call,
             .ops = .extern_fn_reloc,
@@ -15319,7 +15299,7 @@ fn genLazySymbolRef(
     lazy_sym: link.File.LazySymbol,
 ) InnerError!void {
     const pt = self.pt;
-    if (self.bin_file.cast(link.File.Elf)) |elf_file| {
+    if (self.bin_file.cast(.elf)) |elf_file| {
         const zo = elf_file.zigObjectPtr().?;
         const sym_index = zo.getOrCreateMetadataForLazySymbol(elf_file, pt, lazy_sym) catch |err|
             return self.fail("{s} creating lazy symbol", .{@errorName(err)});
@@ -15355,7 +15335,7 @@ fn genLazySymbolRef(
                 else => unreachable,
             }
         }
-    } else if (self.bin_file.cast(link.File.Plan9)) |p9_file| {
+    } else if (self.bin_file.cast(.plan9)) |p9_file| {
         const atom_index = p9_file.getOrCreateAtomForLazySymbol(pt, lazy_sym) catch |err|
             return self.fail("{s} creating lazy symbol", .{@errorName(err)});
         var atom = p9_file.getAtom(atom_index);
@@ -15382,7 +15362,7 @@ fn genLazySymbolRef(
             ),
             else => unreachable,
         }
-    } else if (self.bin_file.cast(link.File.Coff)) |coff_file| {
+    } else if (self.bin_file.cast(.coff)) |coff_file| {
         const atom_index = coff_file.getOrCreateAtomForLazySymbol(pt, lazy_sym) catch |err|
             return self.fail("{s} creating lazy symbol", .{@errorName(err)});
         const sym_index = coff_file.getAtom(atom_index).getSymbolIndex().?;
@@ -15396,7 +15376,7 @@ fn genLazySymbolRef(
             .call => try self.asmRegister(.{ ._, .call }, reg),
             else => unreachable,
         }
-    } else if (self.bin_file.cast(link.File.MachO)) |macho_file| {
+    } else if (self.bin_file.cast(.macho)) |macho_file| {
         const zo = macho_file.getZigObject().?;
         const sym_index = zo.getOrCreateMetadataForLazySymbol(macho_file, pt, lazy_sym) catch |err|
             return self.fail("{s} creating lazy symbol", .{@errorName(err)});
@@ -16361,7 +16341,6 @@ fn airMemcpy(self: *Self, inst: Air.Inst.Index) !void {
 
 fn airTagName(self: *Self, inst: Air.Inst.Index) !void {
     const pt = self.pt;
-    const mod = pt.zcu;
     const un_op = self.air.instructions.items(.data)[@intFromEnum(inst)].un_op;
     const inst_ty = self.typeOfIndex(inst);
     const enum_ty = self.typeOf(un_op);
@@ -16393,18 +16372,13 @@ fn airTagName(self: *Self, inst: Air.Inst.Index) !void {
     const operand = try self.resolveInst(un_op);
     try self.genSetReg(param_regs[1], enum_ty, operand, .{});
 
-    try self.genLazySymbolRef(
-        .call,
-        .rax,
-        link.File.LazySymbol.initDecl(.code, enum_ty.getOwnerDecl(mod), mod),
-    );
+    const enum_lazy_sym: link.File.LazySymbol = .{ .kind = .code, .ty = enum_ty.toIntern() };
+    try self.genLazySymbolRef(.call, .rax, enum_lazy_sym);
 
     return self.finishAir(inst, dst_mcv, .{ un_op, .none, .none });
 }
 
 fn airErrorName(self: *Self, inst: Air.Inst.Index) !void {
-    const pt = self.pt;
-    const mod = pt.zcu;
     const un_op = self.air.instructions.items(.data)[@intFromEnum(inst)].un_op;
 
     const err_ty = self.typeOf(un_op);
@@ -16416,7 +16390,8 @@ fn airErrorName(self: *Self, inst: Air.Inst.Index) !void {
     const addr_reg = try self.register_manager.allocReg(null, abi.RegisterClass.gp);
     const addr_lock = self.register_manager.lockRegAssumeUnused(addr_reg);
     defer self.register_manager.unlockReg(addr_lock);
-    try self.genLazySymbolRef(.lea, addr_reg, link.File.LazySymbol.initDecl(.const_data, null, mod));
+    const anyerror_lazy_sym: link.File.LazySymbol = .{ .kind = .const_data, .ty = .anyerror_type };
+    try self.genLazySymbolRef(.lea, addr_reg, anyerror_lazy_sym);
 
     const start_reg = try self.register_manager.allocReg(null, abi.RegisterClass.gp);
     const start_lock = self.register_manager.lockRegAssumeUnused(start_reg);
@@ -18808,7 +18783,7 @@ fn limitImmediateType(self: *Self, operand: Air.Inst.Ref, comptime T: type) !MCV
 
 fn genTypedValue(self: *Self, val: Value) InnerError!MCValue {
     const pt = self.pt;
-    return switch (try codegen.genTypedValue(self.bin_file, pt, self.src_loc, val, self.owner.getDecl(pt.zcu))) {
+    return switch (try codegen.genTypedValue(self.bin_file, pt, self.src_loc, val, self.target.*)) {
         .mcv => |mcv| switch (mcv) {
             .none => .none,
             .undef => .undef,