compiler: move unions into InternPool

There are a couple concepts here worth understanding:

Key.UnionType - This type is available *before* resolving the union's
fields. The enum tag type, number of fields, and field names, field
types, and field alignments are not available with this.

InternPool.UnionType - This one can be obtained from the above type with
`InternPool.loadUnionType` which asserts that the union's enum tag type
has been resolved. This one has all the information available.

Additionally:

* ZIR: Turn an unused bit into `any_aligned_fields` flag to help
  semantic analysis know whether a union has explicit alignment on any
  fields (usually not).
* Sema: delete `resolveTypeRequiresComptime` which had the same type
  signature and near-duplicate logic to `typeRequiresComptime`.
  - Make opaque types not report comptime-only (this was inconsistent
    between the two implementations of this function).
* Implement accepted proposal #12556 which is a breaking change.

1 files changed, 11 insertions, 11 deletions

diff --git a/src/codegen.zig b/src/codegen.zig
index c1a956a765..3a802f4d86 100644
--- a/src/codegen.zig
+++ b/src/codegen.zig
@@ -185,8 +185,9 @@ pub fn generateSymbol(
     defer tracy.end();
 
     const mod = bin_file.options.module.?;
+    const ip = &mod.intern_pool;
     var typed_value = arg_tv;
-    switch (mod.intern_pool.indexToKey(typed_value.val.toIntern())) {
+    switch (ip.indexToKey(typed_value.val.toIntern())) {
         .runtime_value => |rt| typed_value.val = rt.val.toValue(),
         else => {},
     }
@@ -205,7 +206,7 @@ pub fn generateSymbol(
         return .ok;
     }
 
-    switch (mod.intern_pool.indexToKey(typed_value.val.toIntern())) {
+    switch (ip.indexToKey(typed_value.val.toIntern())) {
         .int_type,
         .ptr_type,
         .array_type,
@@ -385,7 +386,7 @@ pub fn generateSymbol(
                 try code.appendNTimes(0, padding);
             }
         },
-        .aggregate => |aggregate| switch (mod.intern_pool.indexToKey(typed_value.ty.toIntern())) {
+        .aggregate => |aggregate| switch (ip.indexToKey(typed_value.ty.toIntern())) {
             .array_type => |array_type| switch (aggregate.storage) {
                 .bytes => |bytes| try code.appendSlice(bytes),
                 .elems, .repeated_elem => {
@@ -442,7 +443,7 @@ pub fn generateSymbol(
                     if (!field_ty.toType().hasRuntimeBits(mod)) continue;
 
                     const field_val = switch (aggregate.storage) {
-                        .bytes => |bytes| try mod.intern_pool.get(mod.gpa, .{ .int = .{
+                        .bytes => |bytes| try ip.get(mod.gpa, .{ .int = .{
                             .ty = field_ty,
                             .storage = .{ .u64 = bytes[index] },
                         } }),
@@ -484,7 +485,7 @@ pub fn generateSymbol(
                         const field_ty = field.ty;
 
                         const field_val = switch (aggregate.storage) {
-                            .bytes => |bytes| try mod.intern_pool.get(mod.gpa, .{ .int = .{
+                            .bytes => |bytes| try ip.get(mod.gpa, .{ .int = .{
                                 .ty = field_ty.toIntern(),
                                 .storage = .{ .u64 = bytes[index] },
                             } }),
@@ -522,8 +523,8 @@ pub fn generateSymbol(
 
                         if (!field_ty.hasRuntimeBits(mod)) continue;
 
-                        const field_val = switch (mod.intern_pool.indexToKey(typed_value.val.toIntern()).aggregate.storage) {
-                            .bytes => |bytes| try mod.intern_pool.get(mod.gpa, .{ .int = .{
+                        const field_val = switch (ip.indexToKey(typed_value.val.toIntern()).aggregate.storage) {
+                            .bytes => |bytes| try ip.get(mod.gpa, .{ .int = .{
                                 .ty = field_ty.toIntern(),
                                 .storage = .{ .u64 = bytes[field_offset.field] },
                             } }),
@@ -570,10 +571,9 @@ pub fn generateSymbol(
                 }
             }
 
-            const union_ty = mod.typeToUnion(typed_value.ty).?;
+            const union_obj = mod.typeToUnion(typed_value.ty).?;
             const field_index = typed_value.ty.unionTagFieldIndex(un.tag.toValue(), mod).?;
-            assert(union_ty.haveFieldTypes());
-            const field_ty = union_ty.fields.values()[field_index].ty;
+            const field_ty = union_obj.field_types.get(ip)[field_index].toType();
             if (!field_ty.hasRuntimeBits(mod)) {
                 try code.appendNTimes(0xaa, math.cast(usize, layout.payload_size) orelse return error.Overflow);
             } else {
@@ -593,7 +593,7 @@ pub fn generateSymbol(
 
             if (layout.tag_size > 0 and layout.tag_align < layout.payload_align) {
                 switch (try generateSymbol(bin_file, src_loc, .{
-                    .ty = union_ty.tag_ty,
+                    .ty = union_obj.enum_tag_ty.toType(),
                     .val = un.tag.toValue(),
                 }, code, debug_output, reloc_info)) {
                     .ok => {},