InternPool: port most of value tags

9 files changed, 76 insertions, 70 deletions

diff --git a/src/link/C.zig b/src/link/C.zig
index 1a25bfe231..c871d8a02a 100644
--- a/src/link/C.zig
+++ b/src/link/C.zig
@@ -87,12 +87,13 @@ pub fn freeDecl(self: *C, decl_index: Module.Decl.Index) void {
     }
 }
 
-pub fn updateFunc(self: *C, module: *Module, func: *Module.Fn, air: Air, liveness: Liveness) !void {
+pub fn updateFunc(self: *C, module: *Module, func_index: Module.Fn.Index, air: Air, liveness: Liveness) !void {
     const tracy = trace(@src());
     defer tracy.end();
 
     const gpa = self.base.allocator;
 
+    const func = module.funcPtr(func_index);
     const decl_index = func.owner_decl;
     const gop = try self.decl_table.getOrPut(gpa, decl_index);
     if (!gop.found_existing) {
@@ -111,7 +112,7 @@ pub fn updateFunc(self: *C, module: *Module, func: *Module.Fn, air: Air, livenes
         .value_map = codegen.CValueMap.init(gpa),
         .air = air,
         .liveness = liveness,
-        .func = func,
+        .func_index = func_index,
         .object = .{
             .dg = .{
                 .gpa = gpa,
@@ -555,7 +556,8 @@ fn flushDecl(
     export_names: std.StringHashMapUnmanaged(void),
 ) FlushDeclError!void {
     const gpa = self.base.allocator;
-    const decl = self.base.options.module.?.declPtr(decl_index);
+    const mod = self.base.options.module.?;
+    const decl = mod.declPtr(decl_index);
     // Before flushing any particular Decl we must ensure its
     // dependencies are already flushed, so that the order in the .c
     // file comes out correctly.
@@ -569,7 +571,7 @@ fn flushDecl(
 
     try self.flushLazyFns(f, decl_block.lazy_fns);
     try f.all_buffers.ensureUnusedCapacity(gpa, 1);
-    if (!(decl.isExtern() and export_names.contains(mem.span(decl.name))))
+    if (!(decl.isExtern(mod) and export_names.contains(mem.span(decl.name))))
         f.appendBufAssumeCapacity(decl_block.fwd_decl.items);
 }
 
diff --git a/src/link/Coff.zig b/src/link/Coff.zig
index efaeebc62e..f4ee2fde97 100644
--- a/src/link/Coff.zig
+++ b/src/link/Coff.zig
@@ -1032,18 +1032,19 @@ fn freeAtom(self: *Coff, atom_index: Atom.Index) void {
     self.getAtomPtr(atom_index).sym_index = 0;
 }
 
-pub fn updateFunc(self: *Coff, mod: *Module, func: *Module.Fn, air: Air, liveness: Liveness) !void {
+pub fn updateFunc(self: *Coff, mod: *Module, func_index: Module.Fn.Index, air: Air, liveness: Liveness) !void {
     if (build_options.skip_non_native and builtin.object_format != .coff) {
         @panic("Attempted to compile for object format that was disabled by build configuration");
     }
     if (build_options.have_llvm) {
         if (self.llvm_object) |llvm_object| {
-            return llvm_object.updateFunc(mod, func, air, liveness);
+            return llvm_object.updateFunc(mod, func_index, air, liveness);
         }
     }
     const tracy = trace(@src());
     defer tracy.end();
 
+    const func = mod.funcPtr(func_index);
     const decl_index = func.owner_decl;
     const decl = mod.declPtr(decl_index);
 
@@ -1057,7 +1058,7 @@ pub fn updateFunc(self: *Coff, mod: *Module, func: *Module.Fn, air: Air, livenes
     const res = try codegen.generateFunction(
         &self.base,
         decl.srcLoc(mod),
-        func,
+        func_index,
         air,
         liveness,
         &code_buffer,
@@ -1155,11 +1156,10 @@ pub fn updateDecl(
 
     const decl = mod.declPtr(decl_index);
 
-    if (decl.val.tag() == .extern_fn) {
+    if (decl.getExternFunc(mod)) |_| {
         return; // TODO Should we do more when front-end analyzed extern decl?
     }
-    if (decl.val.castTag(.variable)) |payload| {
-        const variable = payload.data;
+    if (decl.getVariable(mod)) |variable| {
         if (variable.is_extern) {
             return; // TODO Should we do more when front-end analyzed extern decl?
         }
@@ -1172,7 +1172,7 @@ pub fn updateDecl(
     var code_buffer = std.ArrayList(u8).init(self.base.allocator);
     defer code_buffer.deinit();
 
-    const decl_val = if (decl.val.castTag(.variable)) |payload| payload.data.init else decl.val;
+    const decl_val = if (decl.getVariable(mod)) |variable| variable.init.toValue() else decl.val;
     const res = try codegen.generateSymbol(&self.base, decl.srcLoc(mod), .{
         .ty = decl.ty,
         .val = decl_val,
@@ -1313,7 +1313,7 @@ fn getDeclOutputSection(self: *Coff, decl_index: Module.Decl.Index) u16 {
             // TODO: what if this is a function pointer?
             .Fn => break :blk self.text_section_index.?,
             else => {
-                if (val.castTag(.variable)) |_| {
+                if (decl.getVariable(mod)) |_| {
                     break :blk self.data_section_index.?;
                 }
                 break :blk self.rdata_section_index.?;
@@ -1425,7 +1425,7 @@ pub fn updateDeclExports(
         // detect the default subsystem.
         for (exports) |exp| {
             const exported_decl = mod.declPtr(exp.exported_decl);
-            if (exported_decl.getFunction() == null) continue;
+            if (exported_decl.getFunctionIndex(mod) == .none) continue;
             const winapi_cc = switch (self.base.options.target.cpu.arch) {
                 .x86 => std.builtin.CallingConvention.Stdcall,
                 else => std.builtin.CallingConvention.C,
diff --git a/src/link/Dwarf.zig b/src/link/Dwarf.zig
index ed2883f4da..d6dd6979ea 100644
--- a/src/link/Dwarf.zig
+++ b/src/link/Dwarf.zig
@@ -971,7 +971,7 @@ pub fn initDeclState(self: *Dwarf, mod: *Module, decl_index: Module.Decl.Index)
             // For functions we need to add a prologue to the debug line program.
             try dbg_line_buffer.ensureTotalCapacity(26);
 
-            const func = decl.val.castTag(.function).?.data;
+            const func = decl.getFunction(mod).?;
             log.debug("decl.src_line={d}, func.lbrace_line={d}, func.rbrace_line={d}", .{
                 decl.src_line,
                 func.lbrace_line,
@@ -1514,7 +1514,7 @@ fn writeDeclDebugInfo(self: *Dwarf, atom_index: Atom.Index, dbg_info_buf: []cons
     }
 }
 
-pub fn updateDeclLineNumber(self: *Dwarf, module: *Module, decl_index: Module.Decl.Index) !void {
+pub fn updateDeclLineNumber(self: *Dwarf, mod: *Module, decl_index: Module.Decl.Index) !void {
     const tracy = trace(@src());
     defer tracy.end();
 
@@ -1522,8 +1522,8 @@ pub fn updateDeclLineNumber(self: *Dwarf, module: *Module, decl_index: Module.De
     const atom = self.getAtom(.src_fn, atom_index);
     if (atom.len == 0) return;
 
-    const decl = module.declPtr(decl_index);
-    const func = decl.val.castTag(.function).?.data;
+    const decl = mod.declPtr(decl_index);
+    const func = decl.getFunction(mod).?;
     log.debug("decl.src_line={d}, func.lbrace_line={d}, func.rbrace_line={d}", .{
         decl.src_line,
         func.lbrace_line,
diff --git a/src/link/Elf.zig b/src/link/Elf.zig
index b27967884e..476b939038 100644
--- a/src/link/Elf.zig
+++ b/src/link/Elf.zig
@@ -2465,7 +2465,7 @@ fn getDeclShdrIndex(self: *Elf, decl_index: Module.Decl.Index) u16 {
             // TODO: what if this is a function pointer?
             .Fn => break :blk self.text_section_index.?,
             else => {
-                if (val.castTag(.variable)) |_| {
+                if (decl.getVariable(mod)) |_| {
                     break :blk self.data_section_index.?;
                 }
                 break :blk self.rodata_section_index.?;
@@ -2574,17 +2574,18 @@ fn updateDeclCode(self: *Elf, decl_index: Module.Decl.Index, code: []const u8, s
     return local_sym;
 }
 
-pub fn updateFunc(self: *Elf, mod: *Module, func: *Module.Fn, air: Air, liveness: Liveness) !void {
+pub fn updateFunc(self: *Elf, mod: *Module, func_index: Module.Fn.Index, air: Air, liveness: Liveness) !void {
     if (build_options.skip_non_native and builtin.object_format != .elf) {
         @panic("Attempted to compile for object format that was disabled by build configuration");
     }
     if (build_options.have_llvm) {
-        if (self.llvm_object) |llvm_object| return llvm_object.updateFunc(mod, func, air, liveness);
+        if (self.llvm_object) |llvm_object| return llvm_object.updateFunc(mod, func_index, air, liveness);
     }
 
     const tracy = trace(@src());
     defer tracy.end();
 
+    const func = mod.funcPtr(func_index);
     const decl_index = func.owner_decl;
     const decl = mod.declPtr(decl_index);
 
@@ -2599,11 +2600,11 @@ pub fn updateFunc(self: *Elf, mod: *Module, func: *Module.Fn, air: Air, liveness
     defer if (decl_state) |*ds| ds.deinit();
 
     const res = if (decl_state) |*ds|
-        try codegen.generateFunction(&self.base, decl.srcLoc(mod), func, air, liveness, &code_buffer, .{
+        try codegen.generateFunction(&self.base, decl.srcLoc(mod), func_index, air, liveness, &code_buffer, .{
             .dwarf = ds,
         })
     else
-        try codegen.generateFunction(&self.base, decl.srcLoc(mod), func, air, liveness, &code_buffer, .none);
+        try codegen.generateFunction(&self.base, decl.srcLoc(mod), func_index, air, liveness, &code_buffer, .none);
 
     const code = switch (res) {
         .ok => code_buffer.items,
@@ -2646,11 +2647,10 @@ pub fn updateDecl(
 
     const decl = mod.declPtr(decl_index);
 
-    if (decl.val.tag() == .extern_fn) {
+    if (decl.getExternFunc(mod)) |_| {
         return; // TODO Should we do more when front-end analyzed extern decl?
     }
-    if (decl.val.castTag(.variable)) |payload| {
-        const variable = payload.data;
+    if (decl.getVariable(mod)) |variable| {
         if (variable.is_extern) {
             return; // TODO Should we do more when front-end analyzed extern decl?
         }
@@ -2667,7 +2667,7 @@ pub fn updateDecl(
     defer if (decl_state) |*ds| ds.deinit();
 
     // TODO implement .debug_info for global variables
-    const decl_val = if (decl.val.castTag(.variable)) |payload| payload.data.init else decl.val;
+    const decl_val = if (decl.getVariable(mod)) |variable| variable.init.toValue() else decl.val;
     const res = if (decl_state) |*ds|
         try codegen.generateSymbol(&self.base, decl.srcLoc(mod), .{
             .ty = decl.ty,
diff --git a/src/link/MachO.zig b/src/link/MachO.zig
index e7723595db..ffbdcdb91f 100644
--- a/src/link/MachO.zig
+++ b/src/link/MachO.zig
@@ -1847,16 +1847,17 @@ fn addStubEntry(self: *MachO, target: SymbolWithLoc) !void {
     self.markRelocsDirtyByTarget(target);
 }
 
-pub fn updateFunc(self: *MachO, mod: *Module, func: *Module.Fn, air: Air, liveness: Liveness) !void {
+pub fn updateFunc(self: *MachO, mod: *Module, func_index: Module.Fn.Index, air: Air, liveness: Liveness) !void {
     if (build_options.skip_non_native and builtin.object_format != .macho) {
         @panic("Attempted to compile for object format that was disabled by build configuration");
     }
     if (build_options.have_llvm) {
-        if (self.llvm_object) |llvm_object| return llvm_object.updateFunc(mod, func, air, liveness);
+        if (self.llvm_object) |llvm_object| return llvm_object.updateFunc(mod, func_index, air, liveness);
     }
     const tracy = trace(@src());
     defer tracy.end();
 
+    const func = mod.funcPtr(func_index);
     const decl_index = func.owner_decl;
     const decl = mod.declPtr(decl_index);
 
@@ -1874,11 +1875,11 @@ pub fn updateFunc(self: *MachO, mod: *Module, func: *Module.Fn, air: Air, livene
     defer if (decl_state) |*ds| ds.deinit();
 
     const res = if (decl_state) |*ds|
-        try codegen.generateFunction(&self.base, decl.srcLoc(mod), func, air, liveness, &code_buffer, .{
+        try codegen.generateFunction(&self.base, decl.srcLoc(mod), func_index, air, liveness, &code_buffer, .{
             .dwarf = ds,
         })
     else
-        try codegen.generateFunction(&self.base, decl.srcLoc(mod), func, air, liveness, &code_buffer, .none);
+        try codegen.generateFunction(&self.base, decl.srcLoc(mod), func_index, air, liveness, &code_buffer, .none);
 
     var code = switch (res) {
         .ok => code_buffer.items,
@@ -1983,18 +1984,17 @@ pub fn updateDecl(self: *MachO, mod: *Module, decl_index: Module.Decl.Index) !vo
 
     const decl = mod.declPtr(decl_index);
 
-    if (decl.val.tag() == .extern_fn) {
+    if (decl.getExternFunc(mod)) |_| {
         return; // TODO Should we do more when front-end analyzed extern decl?
     }
-    if (decl.val.castTag(.variable)) |payload| {
-        const variable = payload.data;
+    if (decl.getVariable(mod)) |variable| {
         if (variable.is_extern) {
             return; // TODO Should we do more when front-end analyzed extern decl?
         }
     }
 
-    const is_threadlocal = if (decl.val.castTag(.variable)) |payload|
-        payload.data.is_threadlocal and !self.base.options.single_threaded
+    const is_threadlocal = if (decl.getVariable(mod)) |variable|
+        variable.is_threadlocal and !self.base.options.single_threaded
     else
         false;
     if (is_threadlocal) return self.updateThreadlocalVariable(mod, decl_index);
@@ -2012,7 +2012,7 @@ pub fn updateDecl(self: *MachO, mod: *Module, decl_index: Module.Decl.Index) !vo
         null;
     defer if (decl_state) |*ds| ds.deinit();
 
-    const decl_val = if (decl.val.castTag(.variable)) |payload| payload.data.init else decl.val;
+    const decl_val = if (decl.getVariable(mod)) |variable| variable.init.toValue() else decl.val;
     const res = if (decl_state) |*ds|
         try codegen.generateSymbol(&self.base, decl.srcLoc(mod), .{
             .ty = decl.ty,
@@ -2177,7 +2177,7 @@ fn updateThreadlocalVariable(self: *MachO, module: *Module, decl_index: Module.D
 
     const decl = module.declPtr(decl_index);
     const decl_metadata = self.decls.get(decl_index).?;
-    const decl_val = decl.val.castTag(.variable).?.data.init;
+    const decl_val = decl.getVariable(mod).?.init.toValue();
     const res = if (decl_state) |*ds|
         try codegen.generateSymbol(&self.base, decl.srcLoc(mod), .{
             .ty = decl.ty,
@@ -2278,8 +2278,8 @@ fn getDeclOutputSection(self: *MachO, decl_index: Module.Decl.Index) u8 {
             }
         }
 
-        if (val.castTag(.variable)) |variable| {
-            if (variable.data.is_threadlocal and !single_threaded) {
+        if (decl.getVariable(mod)) |variable| {
+            if (variable.is_threadlocal and !single_threaded) {
                 break :blk self.thread_data_section_index.?;
             }
             break :blk self.data_section_index.?;
@@ -2289,7 +2289,7 @@ fn getDeclOutputSection(self: *MachO, decl_index: Module.Decl.Index) u8 {
             // TODO: what if this is a function pointer?
             .Fn => break :blk self.text_section_index.?,
             else => {
-                if (val.castTag(.variable)) |_| {
+                if (decl.getVariable(mod)) |_| {
                     break :blk self.data_section_index.?;
                 }
                 break :blk self.data_const_section_index.?;
diff --git a/src/link/NvPtx.zig b/src/link/NvPtx.zig
index 69cd73a602..b74518d930 100644
--- a/src/link/NvPtx.zig
+++ b/src/link/NvPtx.zig
@@ -68,9 +68,9 @@ pub fn deinit(self: *NvPtx) void {
     self.base.allocator.free(self.ptx_file_name);
 }
 
-pub fn updateFunc(self: *NvPtx, module: *Module, func: *Module.Fn, air: Air, liveness: Liveness) !void {
+pub fn updateFunc(self: *NvPtx, module: *Module, func_index: Module.Fn.Index, air: Air, liveness: Liveness) !void {
     if (!build_options.have_llvm) return;
-    try self.llvm_object.updateFunc(module, func, air, liveness);
+    try self.llvm_object.updateFunc(module, func_index, air, liveness);
 }
 
 pub fn updateDecl(self: *NvPtx, module: *Module, decl_index: Module.Decl.Index) !void {
diff --git a/src/link/Plan9.zig b/src/link/Plan9.zig
index 968cbb0e7e..2071833b93 100644
--- a/src/link/Plan9.zig
+++ b/src/link/Plan9.zig
@@ -276,11 +276,12 @@ fn addPathComponents(self: *Plan9, path: []const u8, a: *std.ArrayList(u8)) !voi
     }
 }
 
-pub fn updateFunc(self: *Plan9, mod: *Module, func: *Module.Fn, air: Air, liveness: Liveness) !void {
+pub fn updateFunc(self: *Plan9, mod: *Module, func_index: Module.Fn.Index, air: Air, liveness: Liveness) !void {
     if (build_options.skip_non_native and builtin.object_format != .plan9) {
         @panic("Attempted to compile for object format that was disabled by build configuration");
     }
 
+    const func = mod.funcPtr(func_index);
     const decl_index = func.owner_decl;
     const decl = mod.declPtr(decl_index);
     self.freeUnnamedConsts(decl_index);
@@ -299,7 +300,7 @@ pub fn updateFunc(self: *Plan9, mod: *Module, func: *Module.Fn, air: Air, livene
     const res = try codegen.generateFunction(
         &self.base,
         decl.srcLoc(mod),
-        func,
+        func_index,
         air,
         liveness,
         &code_buffer,
@@ -391,11 +392,10 @@ pub fn lowerUnnamedConst(self: *Plan9, tv: TypedValue, decl_index: Module.Decl.I
 pub fn updateDecl(self: *Plan9, mod: *Module, decl_index: Module.Decl.Index) !void {
     const decl = mod.declPtr(decl_index);
 
-    if (decl.val.tag() == .extern_fn) {
+    if (decl.getExternFunc(mod)) |_| {
         return; // TODO Should we do more when front-end analyzed extern decl?
     }
-    if (decl.val.castTag(.variable)) |payload| {
-        const variable = payload.data;
+    if (decl.getVariable(mod)) |variable| {
         if (variable.is_extern) {
             return; // TODO Should we do more when front-end analyzed extern decl?
         }
@@ -407,7 +407,7 @@ pub fn updateDecl(self: *Plan9, mod: *Module, decl_index: Module.Decl.Index) !vo
 
     var code_buffer = std.ArrayList(u8).init(self.base.allocator);
     defer code_buffer.deinit();
-    const decl_val = if (decl.val.castTag(.variable)) |payload| payload.data.init else decl.val;
+    const decl_val = if (decl.getVariable(mod)) |variable| variable.init.toValue() else decl.val;
     // TODO we need the symbol index for symbol in the table of locals for the containing atom
     const res = try codegen.generateSymbol(&self.base, decl.srcLoc(mod), .{
         .ty = decl.ty,
@@ -771,7 +771,7 @@ pub fn freeDecl(self: *Plan9, decl_index: Module.Decl.Index) void {
     // in the deleteUnusedDecl function.
     const mod = self.base.options.module.?;
     const decl = mod.declPtr(decl_index);
-    const is_fn = (decl.val.tag() == .function);
+    const is_fn = decl.getFunctionIndex(mod) != .none;
     if (is_fn) {
         var symidx_and_submap = self.fn_decl_table.get(decl.getFileScope(mod)).?;
         var submap = symidx_and_submap.functions;
diff --git a/src/link/SpirV.zig b/src/link/SpirV.zig
index da25753b95..0a6608303e 100644
--- a/src/link/SpirV.zig
+++ b/src/link/SpirV.zig
@@ -103,11 +103,13 @@ pub fn deinit(self: *SpirV) void {
     self.decl_link.deinit();
 }
 
-pub fn updateFunc(self: *SpirV, module: *Module, func: *Module.Fn, air: Air, liveness: Liveness) !void {
+pub fn updateFunc(self: *SpirV, module: *Module, func_index: Module.Fn.Index, air: Air, liveness: Liveness) !void {
     if (build_options.skip_non_native) {
         @panic("Attempted to compile for architecture that was disabled by build configuration");
     }
 
+    const func = module.funcPtr(func_index);
+
     var decl_gen = codegen.DeclGen.init(self.base.allocator, module, &self.spv, &self.decl_link);
     defer decl_gen.deinit();
 
@@ -136,7 +138,7 @@ pub fn updateDeclExports(
     exports: []const *Module.Export,
 ) !void {
     const decl = mod.declPtr(decl_index);
-    if (decl.val.tag() == .function and decl.ty.fnCallingConvention(mod) == .Kernel) {
+    if (decl.getFunctionIndex(mod) != .none and decl.ty.fnCallingConvention(mod) == .Kernel) {
         // TODO: Unify with resolveDecl in spirv.zig.
         const entry = try self.decl_link.getOrPut(decl_index);
         if (!entry.found_existing) {
diff --git a/src/link/Wasm.zig b/src/link/Wasm.zig
index ef97a7fa7f..78d1be978b 100644
--- a/src/link/Wasm.zig
+++ b/src/link/Wasm.zig
@@ -1324,17 +1324,18 @@ pub fn allocateSymbol(wasm: *Wasm) !u32 {
     return index;
 }
 
-pub fn updateFunc(wasm: *Wasm, mod: *Module, func: *Module.Fn, air: Air, liveness: Liveness) !void {
+pub fn updateFunc(wasm: *Wasm, mod: *Module, func_index: Module.Fn.Index, air: Air, liveness: Liveness) !void {
     if (build_options.skip_non_native and builtin.object_format != .wasm) {
         @panic("Attempted to compile for object format that was disabled by build configuration");
     }
     if (build_options.have_llvm) {
-        if (wasm.llvm_object) |llvm_object| return llvm_object.updateFunc(mod, func, air, liveness);
+        if (wasm.llvm_object) |llvm_object| return llvm_object.updateFunc(mod, func_index, air, liveness);
     }
 
     const tracy = trace(@src());
     defer tracy.end();
 
+    const func = mod.funcPtr(func_index);
     const decl_index = func.owner_decl;
     const decl = mod.declPtr(decl_index);
     const atom_index = try wasm.getOrCreateAtomForDecl(decl_index);
@@ -1358,7 +1359,7 @@ pub fn updateFunc(wasm: *Wasm, mod: *Module, func: *Module.Fn, air: Air, livenes
     const result = try codegen.generateFunction(
         &wasm.base,
         decl.srcLoc(mod),
-        func,
+        func_index,
         air,
         liveness,
         &code_writer,
@@ -1403,9 +1404,9 @@ pub fn updateDecl(wasm: *Wasm, mod: *Module, decl_index: Module.Decl.Index) !voi
     defer tracy.end();
 
     const decl = mod.declPtr(decl_index);
-    if (decl.val.castTag(.function)) |_| {
+    if (decl.getFunction(mod)) |_| {
         return;
-    } else if (decl.val.castTag(.extern_fn)) |_| {
+    } else if (decl.getExternFunc(mod)) |_| {
         return;
     }
 
@@ -1413,12 +1414,13 @@ pub fn updateDecl(wasm: *Wasm, mod: *Module, decl_index: Module.Decl.Index) !voi
     const atom = wasm.getAtomPtr(atom_index);
     atom.clear();
 
-    if (decl.isExtern()) {
-        const variable = decl.getVariable().?;
+    if (decl.isExtern(mod)) {
+        const variable = decl.getVariable(mod).?;
         const name = mem.sliceTo(decl.name, 0);
-        return wasm.addOrUpdateImport(name, atom.sym_index, variable.lib_name, null);
+        const lib_name = mod.intern_pool.stringToSliceUnwrap(variable.lib_name);
+        return wasm.addOrUpdateImport(name, atom.sym_index, lib_name, null);
     }
-    const val = if (decl.val.castTag(.variable)) |payload| payload.data.init else decl.val;
+    const val = if (decl.getVariable(mod)) |variable| variable.init.toValue() else decl.val;
 
     var code_writer = std.ArrayList(u8).init(wasm.base.allocator);
     defer code_writer.deinit();
@@ -1791,7 +1793,7 @@ pub fn freeDecl(wasm: *Wasm, decl_index: Module.Decl.Index) void {
         assert(wasm.symbol_atom.remove(local_atom.symbolLoc()));
     }
 
-    if (decl.isExtern()) {
+    if (decl.isExtern(mod)) {
         _ = wasm.imports.remove(atom.symbolLoc());
     }
     _ = wasm.resolved_symbols.swapRemove(atom.symbolLoc());
@@ -1852,7 +1854,7 @@ pub fn addOrUpdateImport(
     /// Symbol index that is external
     symbol_index: u32,
     /// Optional library name (i.e. `extern "c" fn foo() void`
-    lib_name: ?[*:0]const u8,
+    lib_name: ?[:0]const u8,
     /// The index of the type that represents the function signature
     /// when the extern is a function. When this is null, a data-symbol
     /// is asserted instead.
@@ -1863,7 +1865,7 @@ pub fn addOrUpdateImport(
     // Also mangle the name when the lib name is set and not equal to "C" so imports with the same
     // name but different module can be resolved correctly.
     const mangle_name = lib_name != null and
-        !std.mem.eql(u8, std.mem.sliceTo(lib_name.?, 0), "c");
+        !std.mem.eql(u8, lib_name.?, "c");
     const full_name = if (mangle_name) full_name: {
         break :full_name try std.fmt.allocPrint(wasm.base.allocator, "{s}|{s}", .{ name, lib_name.? });
     } else name;
@@ -1889,7 +1891,7 @@ pub fn addOrUpdateImport(
     if (type_index) |ty_index| {
         const gop = try wasm.imports.getOrPut(wasm.base.allocator, .{ .index = symbol_index, .file = null });
         const module_name = if (lib_name) |l_name| blk: {
-            break :blk mem.sliceTo(l_name, 0);
+            break :blk l_name;
         } else wasm.host_name;
         if (!gop.found_existing) {
             gop.value_ptr.* = .{
@@ -2931,7 +2933,7 @@ pub fn getErrorTableSymbol(wasm: *Wasm) !u32 {
 
     const atom_index = try wasm.createAtom();
     const atom = wasm.getAtomPtr(atom_index);
-    const slice_ty = Type.const_slice_u8_sentinel_0;
+    const slice_ty = Type.slice_const_u8_sentinel_0;
     const mod = wasm.base.options.module.?;
     atom.alignment = slice_ty.abiAlignment(mod);
     const sym_index = atom.sym_index;
@@ -2988,7 +2990,7 @@ fn populateErrorNameTable(wasm: *Wasm) !void {
     for (mod.error_name_list.items) |error_name| {
         const len = @intCast(u32, error_name.len + 1); // names are 0-termianted
 
-        const slice_ty = Type.const_slice_u8_sentinel_0;
+        const slice_ty = Type.slice_const_u8_sentinel_0;
         const offset = @intCast(u32, atom.code.items.len);
         // first we create the data for the slice of the name
         try atom.code.appendNTimes(wasm.base.allocator, 0, 4); // ptr to name, will be relocated
@@ -3366,15 +3368,15 @@ pub fn flushModule(wasm: *Wasm, comp: *Compilation, prog_node: *std.Progress.Nod
         var decl_it = wasm.decls.iterator();
         while (decl_it.next()) |entry| {
             const decl = mod.declPtr(entry.key_ptr.*);
-            if (decl.isExtern()) continue;
+            if (decl.isExtern(mod)) continue;
             const atom_index = entry.value_ptr.*;
             const atom = wasm.getAtomPtr(atom_index);
             if (decl.ty.zigTypeTag(mod) == .Fn) {
                 try wasm.parseAtom(atom_index, .function);
-            } else if (decl.getVariable()) |variable| {
-                if (!variable.is_mutable) {
+            } else if (decl.getVariable(mod)) |variable| {
+                if (variable.is_const) {
                     try wasm.parseAtom(atom_index, .{ .data = .read_only });
-                } else if (variable.init.isUndefDeep(mod)) {
+                } else if (variable.init.toValue().isUndefDeep(mod)) {
                     // for safe build modes, we store the atom in the data segment,
                     // whereas for unsafe build modes we store it in bss.
                     const is_initialized = wasm.base.options.optimize_mode == .Debug or