Commit 80cd53d3bb

David Rubin <daviru007@icloud.com>
2024-08-12 04:28:42
sema: clean-up `{union,struct}FieldAlignment` and friends
My main gripes with this design were that it was incorrectly namespaced, the naming was inconsistent and a bit wrong (`fooAlign` vs `fooAlignment`). This commit moves all the logic from `PerThread.zig` to use the zcu + tid system that the previous couple commits introduce. I've organized and merged the functions to be a bit more specific to their own purpose. - `fieldAlignment` takes a struct or union type, an index, and a Zcu (or the Sema version which takes a Pt), and gives you the alignment of the field at the index. - `structFieldAlignment` takes the field type itself, and provides the logic to handle special cases, such as externs. A design goal I had in mind was to avoid using the word 'struct' in the function name, when it worked for things that aren't structs, such as unions.
1 parent b4bb64c
src/arch/aarch64/abi.zig
@@ -95,7 +95,7 @@ fn countFloats(ty: Type, zcu: *Zcu, maybe_float_bits: *?u16) u8 {
             var count: u8 = 0;
             var i: u32 = 0;
             while (i < fields_len) : (i += 1) {
-                const field_ty = ty.structFieldType(i, zcu);
+                const field_ty = ty.fieldType(i, zcu);
                 const field_count = countFloats(field_ty, zcu, maybe_float_bits);
                 if (field_count == invalid) return invalid;
                 count += field_count;
@@ -130,7 +130,7 @@ pub fn getFloatArrayType(ty: Type, zcu: *Zcu) ?Type {
             const fields_len = ty.structFieldCount(zcu);
             var i: u32 = 0;
             while (i < fields_len) : (i += 1) {
-                const field_ty = ty.structFieldType(i, zcu);
+                const field_ty = ty.fieldType(i, zcu);
                 if (getFloatArrayType(field_ty, zcu)) |some| return some;
             }
             return null;
src/arch/aarch64/CodeGen.zig
@@ -4144,7 +4144,7 @@ fn airStructFieldVal(self: *Self, inst: Air.Inst.Index) !void {
         const zcu = pt.zcu;
         const mcv = try self.resolveInst(operand);
         const struct_ty = self.typeOf(operand);
-        const struct_field_ty = struct_ty.structFieldType(index, zcu);
+        const struct_field_ty = struct_ty.fieldType(index, zcu);
         const struct_field_offset = @as(u32, @intCast(struct_ty.structFieldOffset(index, zcu)));
 
         switch (mcv) {
@@ -5473,10 +5473,10 @@ fn genSetStack(self: *Self, ty: Type, stack_offset: u32, mcv: MCValue) InnerErro
             const reg_lock = self.register_manager.lockReg(rwo.reg);
             defer if (reg_lock) |locked_reg| self.register_manager.unlockReg(locked_reg);
 
-            const wrapped_ty = ty.structFieldType(0, zcu);
+            const wrapped_ty = ty.fieldType(0, zcu);
             try self.genSetStack(wrapped_ty, stack_offset, .{ .register = rwo.reg });
 
-            const overflow_bit_ty = ty.structFieldType(1, zcu);
+            const overflow_bit_ty = ty.fieldType(1, zcu);
             const overflow_bit_offset = @as(u32, @intCast(ty.structFieldOffset(1, zcu)));
             const raw_cond_reg = try self.register_manager.allocReg(null, gp);
             const cond_reg = self.registerAlias(raw_cond_reg, overflow_bit_ty);
src/arch/arm/abi.zig
@@ -44,8 +44,8 @@ pub fn classifyType(ty: Type, zcu: *Zcu, ctx: Context) Class {
             const fields = ty.structFieldCount(zcu);
             var i: u32 = 0;
             while (i < fields) : (i += 1) {
-                const field_ty = ty.structFieldType(i, zcu);
-                const field_alignment = ty.structFieldAlign(i, zcu);
+                const field_ty = ty.fieldType(i, zcu);
+                const field_alignment = ty.fieldAlignment(i, zcu);
                 const field_size = field_ty.bitSize(zcu);
                 if (field_size > 32 or field_alignment.compare(.gt, .@"32")) {
                     return Class.arrSize(bit_size, 64);
@@ -66,7 +66,7 @@ pub fn classifyType(ty: Type, zcu: *Zcu, ctx: Context) Class {
 
             for (union_obj.field_types.get(ip), 0..) |field_ty, field_index| {
                 if (Type.fromInterned(field_ty).bitSize(zcu) > 32 or
-                    Type.unionFieldNormalAlignment(union_obj, @intCast(field_index), zcu).compare(.gt, .@"32"))
+                    ty.fieldAlignment(field_index, zcu).compare(.gt, .@"32"))
                 {
                     return Class.arrSize(bit_size, 64);
                 }
@@ -141,7 +141,7 @@ fn countFloats(ty: Type, zcu: *Zcu, maybe_float_bits: *?u16) u32 {
             var count: u32 = 0;
             var i: u32 = 0;
             while (i < fields_len) : (i += 1) {
-                const field_ty = ty.structFieldType(i, zcu);
+                const field_ty = ty.fieldType(i, zcu);
                 const field_count = countFloats(field_ty, zcu, maybe_float_bits);
                 if (field_count == invalid) return invalid;
                 count += field_count;
src/arch/arm/CodeGen.zig
@@ -2926,7 +2926,7 @@ fn airStructFieldVal(self: *Self, inst: Air.Inst.Index) !void {
         const mcv = try self.resolveInst(operand);
         const struct_ty = self.typeOf(operand);
         const struct_field_offset: u32 = @intCast(struct_ty.structFieldOffset(index, zcu));
-        const struct_field_ty = struct_ty.structFieldType(index, zcu);
+        const struct_field_ty = struct_ty.fieldType(index, zcu);
 
         switch (mcv) {
             .dead, .unreach => unreachable,
@@ -5434,10 +5434,10 @@ fn genSetStack(self: *Self, ty: Type, stack_offset: u32, mcv: MCValue) InnerErro
             const reg_lock = self.register_manager.lockReg(reg);
             defer if (reg_lock) |locked_reg| self.register_manager.unlockReg(locked_reg);
 
-            const wrapped_ty = ty.structFieldType(0, zcu);
+            const wrapped_ty = ty.fieldType(0, zcu);
             try self.genSetStack(wrapped_ty, stack_offset, .{ .register = reg });
 
-            const overflow_bit_ty = ty.structFieldType(1, zcu);
+            const overflow_bit_ty = ty.fieldType(1, zcu);
             const overflow_bit_offset: u32 = @intCast(ty.structFieldOffset(1, zcu));
             const cond_reg = try self.register_manager.allocReg(null, gp);
 
src/arch/riscv64/abi.zig
@@ -26,7 +26,7 @@ pub fn classifyType(ty: Type, zcu: *Zcu) Class {
                 var any_fp = false;
                 var field_count: usize = 0;
                 for (0..ty.structFieldCount(zcu)) |field_index| {
-                    const field_ty = ty.structFieldType(field_index, zcu);
+                    const field_ty = ty.fieldType(field_index, zcu);
                     if (!field_ty.hasRuntimeBitsIgnoreComptime(zcu)) continue;
                     if (field_ty.isRuntimeFloat())
                         any_fp = true
src/arch/riscv64/CodeGen.zig
@@ -4576,7 +4576,7 @@ fn airStructFieldVal(func: *Func, inst: Air.Inst.Index) !void {
     const result: MCValue = if (func.liveness.isUnused(inst)) .unreach else result: {
         const src_mcv = try func.resolveInst(operand);
         const struct_ty = func.typeOf(operand);
-        const field_ty = struct_ty.structFieldType(index, zcu);
+        const field_ty = struct_ty.fieldType(index, zcu);
         if (!field_ty.hasRuntimeBitsIgnoreComptime(zcu)) break :result .none;
 
         const field_off: u32 = switch (struct_ty.containerLayout(zcu)) {
@@ -7882,7 +7882,7 @@ fn airAggregateInit(func: *Func, inst: Air.Inst.Index) !void {
                         const elem_i: u32 = @intCast(elem_i_usize);
                         if ((try result_ty.structFieldValueComptime(pt, elem_i)) != null) continue;
 
-                        const elem_ty = result_ty.structFieldType(elem_i, zcu);
+                        const elem_ty = result_ty.fieldType(elem_i, zcu);
                         const elem_bit_size: u32 = @intCast(elem_ty.bitSize(zcu));
                         if (elem_bit_size > 64) {
                             return func.fail(
@@ -7916,7 +7916,7 @@ fn airAggregateInit(func: *Func, inst: Air.Inst.Index) !void {
                 } else for (elements, 0..) |elem, elem_i| {
                     if ((try result_ty.structFieldValueComptime(pt, elem_i)) != null) continue;
 
-                    const elem_ty = result_ty.structFieldType(elem_i, zcu);
+                    const elem_ty = result_ty.fieldType(elem_i, zcu);
                     const elem_off: i32 = @intCast(result_ty.structFieldOffset(elem_i, zcu));
                     const elem_mcv = try func.resolveInst(elem);
                     try func.genSetMem(.{ .frame = frame_index }, elem_off, elem_ty, elem_mcv);
src/arch/sparc64/CodeGen.zig
@@ -3980,10 +3980,10 @@ fn genSetStack(self: *Self, ty: Type, stack_offset: u32, mcv: MCValue) InnerErro
             const reg_lock = self.register_manager.lockReg(rwo.reg);
             defer if (reg_lock) |locked_reg| self.register_manager.unlockReg(locked_reg);
 
-            const wrapped_ty = ty.structFieldType(0, zcu);
+            const wrapped_ty = ty.fieldType(0, zcu);
             try self.genSetStack(wrapped_ty, stack_offset, .{ .register = rwo.reg });
 
-            const overflow_bit_ty = ty.structFieldType(1, zcu);
+            const overflow_bit_ty = ty.fieldType(1, zcu);
             const overflow_bit_offset = @as(u32, @intCast(ty.structFieldOffset(1, zcu)));
             const cond_reg = try self.register_manager.allocReg(null, gp);
 
src/arch/wasm/abi.zig
@@ -108,7 +108,7 @@ pub fn scalarType(ty: Type, zcu: *Zcu) Type {
                 return scalarType(Type.fromInterned(packed_struct.backingIntTypeUnordered(ip)), zcu);
             } else {
                 assert(ty.structFieldCount(zcu) == 1);
-                return scalarType(ty.structFieldType(0, zcu), zcu);
+                return scalarType(ty.fieldType(0, zcu), zcu);
             }
         },
         .Union => {
src/arch/wasm/CodeGen.zig
@@ -3954,7 +3954,7 @@ fn airStructFieldVal(func: *CodeGen, inst: Air.Inst.Index) InnerError!void {
     const struct_ty = func.typeOf(struct_field.struct_operand);
     const operand = try func.resolveInst(struct_field.struct_operand);
     const field_index = struct_field.field_index;
-    const field_ty = struct_ty.structFieldType(field_index, zcu);
+    const field_ty = struct_ty.fieldType(field_index, zcu);
     if (!field_ty.hasRuntimeBitsIgnoreComptime(zcu)) return func.finishAir(inst, .none, &.{struct_field.struct_operand});
 
     const result: WValue = switch (struct_ty.containerLayout(zcu)) {
@@ -5378,7 +5378,7 @@ fn airAggregateInit(func: *CodeGen, inst: Air.Inst.Index) InnerError!void {
                     for (elements, 0..) |elem, elem_index| {
                         if (try result_ty.structFieldValueComptime(pt, elem_index) != null) continue;
 
-                        const elem_ty = result_ty.structFieldType(elem_index, zcu);
+                        const elem_ty = result_ty.fieldType(elem_index, zcu);
                         const field_offset = result_ty.structFieldOffset(elem_index, zcu);
                         _ = try func.buildPointerOffset(offset, @intCast(field_offset - prev_field_offset), .modify);
                         prev_field_offset = field_offset;
src/arch/x86_64/CodeGen.zig
@@ -4352,14 +4352,14 @@ fn airShlWithOverflow(self: *Self, inst: Air.Inst.Index) !void {
                     try self.genSetMem(
                         .{ .frame = frame_index },
                         @intCast(tuple_ty.structFieldOffset(1, zcu)),
-                        tuple_ty.structFieldType(1, zcu),
+                        tuple_ty.fieldType(1, zcu),
                         .{ .eflags = cc },
                         .{},
                     );
                     try self.genSetMem(
                         .{ .frame = frame_index },
                         @intCast(tuple_ty.structFieldOffset(0, zcu)),
-                        tuple_ty.structFieldType(0, zcu),
+                        tuple_ty.fieldType(0, zcu),
                         partial_mcv,
                         .{},
                     );
@@ -4392,7 +4392,7 @@ fn genSetFrameTruncatedOverflowCompare(
     };
     defer if (src_lock) |lock| self.register_manager.unlockReg(lock);
 
-    const ty = tuple_ty.structFieldType(0, zcu);
+    const ty = tuple_ty.fieldType(0, zcu);
     const int_info = ty.intInfo(zcu);
 
     const hi_bits = (int_info.bits - 1) % 64 + 1;
@@ -4450,7 +4450,7 @@ fn genSetFrameTruncatedOverflowCompare(
     try self.genSetMem(
         .{ .frame = frame_index },
         @intCast(tuple_ty.structFieldOffset(1, zcu)),
-        tuple_ty.structFieldType(1, zcu),
+        tuple_ty.fieldType(1, zcu),
         if (overflow_cc) |_| .{ .register = overflow_reg.to8() } else .{ .eflags = .ne },
         .{},
     );
@@ -4637,7 +4637,7 @@ fn airMulWithOverflow(self: *Self, inst: Air.Inst.Index) !void {
                     try self.genSetMem(
                         .{ .frame = dst_mcv.load_frame.index },
                         @intCast(tuple_ty.structFieldOffset(0, zcu)),
-                        tuple_ty.structFieldType(0, zcu),
+                        tuple_ty.fieldType(0, zcu),
                         result,
                         .{},
                     );
@@ -4649,7 +4649,7 @@ fn airMulWithOverflow(self: *Self, inst: Air.Inst.Index) !void {
                     try self.genSetMem(
                         .{ .frame = dst_mcv.load_frame.index },
                         @intCast(tuple_ty.structFieldOffset(1, zcu)),
-                        tuple_ty.structFieldType(1, zcu),
+                        tuple_ty.fieldType(1, zcu),
                         .{ .eflags = .ne },
                         .{},
                     );
@@ -4761,14 +4761,14 @@ fn airMulWithOverflow(self: *Self, inst: Air.Inst.Index) !void {
                     try self.genSetMem(
                         .{ .frame = dst_mcv.load_frame.index },
                         @intCast(tuple_ty.structFieldOffset(0, zcu)),
-                        tuple_ty.structFieldType(0, zcu),
+                        tuple_ty.fieldType(0, zcu),
                         .{ .register_pair = .{ .rax, .rdx } },
                         .{},
                     );
                     try self.genSetMem(
                         .{ .frame = dst_mcv.load_frame.index },
                         @intCast(tuple_ty.structFieldOffset(1, zcu)),
-                        tuple_ty.structFieldType(1, zcu),
+                        tuple_ty.fieldType(1, zcu),
                         .{ .register = tmp_regs[1] },
                         .{},
                     );
@@ -4816,14 +4816,14 @@ fn airMulWithOverflow(self: *Self, inst: Air.Inst.Index) !void {
                         try self.genSetMem(
                             .{ .frame = frame_index },
                             @intCast(tuple_ty.structFieldOffset(0, zcu)),
-                            tuple_ty.structFieldType(0, zcu),
+                            tuple_ty.fieldType(0, zcu),
                             partial_mcv,
                             .{},
                         );
                         try self.genSetMem(
                             .{ .frame = frame_index },
                             @intCast(tuple_ty.structFieldOffset(1, zcu)),
-                            tuple_ty.structFieldType(1, zcu),
+                            tuple_ty.fieldType(1, zcu),
                             .{ .immediate = 0 }, // cc being set is impossible
                             .{},
                         );
@@ -8143,7 +8143,7 @@ fn airStructFieldVal(self: *Self, inst: Air.Inst.Index) !void {
 
         const container_ty = self.typeOf(operand);
         const container_rc = self.regClassForType(container_ty);
-        const field_ty = container_ty.structFieldType(index, zcu);
+        const field_ty = container_ty.fieldType(index, zcu);
         if (!field_ty.hasRuntimeBitsIgnoreComptime(zcu)) break :result .none;
         const field_rc = self.regClassForType(field_ty);
         const field_is_gp = field_rc.supersetOf(abi.RegisterClass.gp);
@@ -15273,14 +15273,14 @@ fn genSetMem(
                 try self.genSetMem(
                     base,
                     disp + @as(i32, @intCast(ty.structFieldOffset(0, zcu))),
-                    ty.structFieldType(0, zcu),
+                    ty.fieldType(0, zcu),
                     .{ .register = ro.reg },
                     opts,
                 );
                 try self.genSetMem(
                     base,
                     disp + @as(i32, @intCast(ty.structFieldOffset(1, zcu))),
-                    ty.structFieldType(1, zcu),
+                    ty.fieldType(1, zcu),
                     .{ .eflags = ro.eflags },
                     opts,
                 );
@@ -18150,7 +18150,7 @@ fn airAggregateInit(self: *Self, inst: Air.Inst.Index) !void {
                         const elem_i: u32 = @intCast(elem_i_usize);
                         if ((try result_ty.structFieldValueComptime(pt, elem_i)) != null) continue;
 
-                        const elem_ty = result_ty.structFieldType(elem_i, zcu);
+                        const elem_ty = result_ty.fieldType(elem_i, zcu);
                         const elem_bit_size: u32 = @intCast(elem_ty.bitSize(zcu));
                         if (elem_bit_size > 64) {
                             return self.fail(
@@ -18232,7 +18232,7 @@ fn airAggregateInit(self: *Self, inst: Air.Inst.Index) !void {
                 } else for (elements, 0..) |elem, elem_i| {
                     if ((try result_ty.structFieldValueComptime(pt, elem_i)) != null) continue;
 
-                    const elem_ty = result_ty.structFieldType(elem_i, zcu);
+                    const elem_ty = result_ty.fieldType(elem_i, zcu);
                     const elem_off: i32 = @intCast(result_ty.structFieldOffset(elem_i, zcu));
                     const elem_mcv = try self.resolveInst(elem);
                     const mat_elem_mcv = switch (elem_mcv) {
src/codegen/c.zig
@@ -7206,7 +7206,7 @@ fn airAggregateInit(f: *Function, inst: Air.Inst.Index) !CValue {
                     var empty = true;
                     for (0..elements.len) |field_index| {
                         if (inst_ty.structFieldIsComptime(field_index, zcu)) continue;
-                        const field_ty = inst_ty.structFieldType(field_index, zcu);
+                        const field_ty = inst_ty.fieldType(field_index, zcu);
                         if (!field_ty.hasRuntimeBitsIgnoreComptime(zcu)) continue;
 
                         if (!empty) {
@@ -7219,7 +7219,7 @@ fn airAggregateInit(f: *Function, inst: Air.Inst.Index) !CValue {
                     empty = true;
                     for (resolved_elements, 0..) |element, field_index| {
                         if (inst_ty.structFieldIsComptime(field_index, zcu)) continue;
-                        const field_ty = inst_ty.structFieldType(field_index, zcu);
+                        const field_ty = inst_ty.fieldType(field_index, zcu);
                         if (!field_ty.hasRuntimeBitsIgnoreComptime(zcu)) continue;
 
                         if (!empty) try writer.writeAll(", ");
src/codegen/llvm.zig
@@ -2496,16 +2496,10 @@ pub const Object = struct {
                     const field_ty = Type.fromInterned(struct_type.field_types.get(ip)[field_index]);
                     if (!field_ty.hasRuntimeBitsIgnoreComptime(zcu)) continue;
                     const field_size = field_ty.abiSize(zcu);
-                    const field_align = pt.structFieldAlignment(
-                        struct_type.fieldAlign(ip, field_index),
-                        field_ty,
-                        struct_type.layout,
-                    );
+                    const field_align = ty.fieldAlignment(field_index, zcu);
                     const field_offset = ty.structFieldOffset(field_index, zcu);
-
                     const field_name = struct_type.fieldName(ip, field_index).unwrap() orelse
                         try ip.getOrPutStringFmt(gpa, pt.tid, "{d}", .{field_index}, .no_embedded_nulls);
-
                     fields.appendAssumeCapacity(try o.builder.debugMemberType(
                         try o.builder.metadataString(field_name.toSlice(ip)),
                         .none, // File
@@ -2598,7 +2592,7 @@ pub const Object = struct {
                     const field_size = Type.fromInterned(field_ty).abiSize(zcu);
                     const field_align: InternPool.Alignment = switch (union_type.flagsUnordered(ip).layout) {
                         .@"packed" => .none,
-                        .auto, .@"extern" => Type.unionFieldNormalAlignment(union_type, @intCast(field_index), zcu),
+                        .auto, .@"extern" => ty.fieldAlignment(field_index, zcu),
                     };
 
                     const field_name = tag_type.names.get(ip)[field_index];
@@ -3315,11 +3309,7 @@ pub const Object = struct {
                     var it = struct_type.iterateRuntimeOrder(ip);
                     while (it.next()) |field_index| {
                         const field_ty = Type.fromInterned(struct_type.field_types.get(ip)[field_index]);
-                        const field_align = pt.structFieldAlignment(
-                            struct_type.fieldAlign(ip, field_index),
-                            field_ty,
-                            struct_type.layout,
-                        );
+                        const field_align = t.fieldAlignment(field_index, zcu);
                         const field_ty_align = field_ty.abiAlignment(zcu);
                         if (field_align.compare(.lt, field_ty_align)) struct_kind = .@"packed";
                         big_align = big_align.max(field_align);
@@ -4127,11 +4117,7 @@ pub const Object = struct {
                     var field_it = struct_type.iterateRuntimeOrder(ip);
                     while (field_it.next()) |field_index| {
                         const field_ty = Type.fromInterned(struct_type.field_types.get(ip)[field_index]);
-                        const field_align = pt.structFieldAlignment(
-                            struct_type.fieldAlign(ip, field_index),
-                            field_ty,
-                            struct_type.layout,
-                        );
+                        const field_align = ty.fieldAlignment(field_index, zcu);
                         big_align = big_align.max(field_align);
                         const prev_offset = offset;
                         offset = field_align.forward(offset);
@@ -6528,7 +6514,7 @@ pub const FuncGen = struct {
         const struct_ty = self.typeOf(struct_field.struct_operand);
         const struct_llvm_val = try self.resolveInst(struct_field.struct_operand);
         const field_index = struct_field.field_index;
-        const field_ty = struct_ty.structFieldType(field_index, zcu);
+        const field_ty = struct_ty.fieldType(field_index, zcu);
         if (!field_ty.hasRuntimeBitsIgnoreComptime(zcu)) return .none;
 
         if (!isByRef(struct_ty, zcu)) {
@@ -6590,7 +6576,7 @@ pub const FuncGen = struct {
                 const llvm_field_index = o.llvmFieldIndex(struct_ty, field_index).?;
                 const field_ptr =
                     try self.wip.gepStruct(struct_llvm_ty, struct_llvm_val, llvm_field_index, "");
-                const alignment = struct_ty.structFieldAlign(field_index, zcu);
+                const alignment = struct_ty.fieldAlignment(field_index, zcu);
                 const field_ptr_ty = try pt.ptrType(.{
                     .child = field_ty.toIntern(),
                     .flags = .{ .alignment = alignment },
@@ -7471,8 +7457,8 @@ pub const FuncGen = struct {
         assert(self.err_ret_trace != .none);
         const field_ptr =
             try self.wip.gepStruct(struct_llvm_ty, self.err_ret_trace, llvm_field_index, "");
-        const field_alignment = struct_ty.structFieldAlign(field_index, zcu);
-        const field_ty = struct_ty.structFieldType(field_index, zcu);
+        const field_alignment = struct_ty.fieldAlignment(field_index, zcu);
+        const field_ty = struct_ty.fieldType(field_index, zcu);
         const field_ptr_ty = try pt.ptrType(.{
             .child = field_ty.toIntern(),
             .flags = .{ .alignment = field_alignment },
@@ -10080,7 +10066,7 @@ pub const FuncGen = struct {
                         const field_ptr_ty = try pt.ptrType(.{
                             .child = self.typeOf(elem).toIntern(),
                             .flags = .{
-                                .alignment = result_ty.structFieldAlign(i, zcu),
+                                .alignment = result_ty.fieldAlignment(i, zcu),
                             },
                         });
                         try self.store(field_ptr, field_ptr_ty, llvm_elem, .none);
@@ -10185,7 +10171,7 @@ pub const FuncGen = struct {
         const field_ty = Type.fromInterned(union_obj.field_types.get(ip)[extra.field_index]);
         const field_llvm_ty = try o.lowerType(field_ty);
         const field_size = field_ty.abiSize(zcu);
-        const field_align = Type.unionFieldNormalAlignment(union_obj, extra.field_index, zcu);
+        const field_align = union_ty.fieldAlignment(extra.field_index, zcu);
         const llvm_usize = try o.lowerType(Type.usize);
         const usize_zero = try o.builder.intValue(llvm_usize, 0);
 
@@ -11188,7 +11174,7 @@ fn lowerFnRetTy(o: *Object, fn_info: InternPool.Key.FuncType) Allocator.Error!Bu
                             var types_len: usize = 0;
                             var types: [8]Builder.Type = undefined;
                             for (0..return_type.structFieldCount(zcu)) |field_index| {
-                                const field_ty = return_type.structFieldType(field_index, zcu);
+                                const field_ty = return_type.fieldType(field_index, zcu);
                                 if (!field_ty.hasRuntimeBitsIgnoreComptime(zcu)) continue;
                                 types[types_len] = try o.lowerType(field_ty);
                                 types_len += 1;
@@ -11444,7 +11430,7 @@ const ParamTypeIterator = struct {
                         .fields => {
                             it.types_len = 0;
                             for (0..ty.structFieldCount(zcu)) |field_index| {
-                                const field_ty = ty.structFieldType(field_index, zcu);
+                                const field_ty = ty.fieldType(field_index, zcu);
                                 if (!field_ty.hasRuntimeBitsIgnoreComptime(zcu)) continue;
                                 it.types_buffer[it.types_len] = try it.object.lowerType(field_ty);
                                 it.types_len += 1;
src/codegen/spirv.zig
@@ -5148,7 +5148,7 @@ const NavGen = struct {
         const object_ty = self.typeOf(struct_field.struct_operand);
         const object_id = try self.resolve(struct_field.struct_operand);
         const field_index = struct_field.field_index;
-        const field_ty = object_ty.structFieldType(field_index, zcu);
+        const field_ty = object_ty.fieldType(field_index, zcu);
 
         if (!field_ty.hasRuntimeBitsIgnoreComptime(zcu)) return null;
 
src/Sema/bitcast.zig
@@ -542,7 +542,7 @@ const PackValueBits = struct {
                             while (it.next()) |field_idx| {
                                 const want_bit_off = ty.structFieldOffset(field_idx, zcu) * 8;
                                 try pack.padding(want_bit_off - cur_bit_off);
-                                const field_ty = ty.structFieldType(field_idx, zcu);
+                                const field_ty = ty.fieldType(field_idx, zcu);
                                 elems[field_idx] = (try pack.get(field_ty)).toIntern();
                                 cur_bit_off = want_bit_off + field_ty.bitSize(zcu);
                             }
@@ -552,7 +552,7 @@ const PackValueBits = struct {
                             var cur_bit_off: u64 = ty.bitSize(zcu);
                             var it = zcu.typeToStruct(ty).?.iterateRuntimeOrderReverse(ip);
                             while (it.next()) |field_idx| {
-                                const field_ty = ty.structFieldType(field_idx, zcu);
+                                const field_ty = ty.fieldType(field_idx, zcu);
                                 const want_bit_off = ty.structFieldOffset(field_idx, zcu) * 8 + field_ty.bitSize(zcu);
                                 try pack.padding(cur_bit_off - want_bit_off);
                                 elems[field_idx] = (try pack.get(field_ty)).toIntern();
@@ -578,7 +578,7 @@ const PackValueBits = struct {
                     // This is identical between LE and BE targets.
                     const elems = try arena.alloc(InternPool.Index, ty.structFieldCount(zcu));
                     for (elems, 0..) |*elem, i| {
-                        const field_ty = ty.structFieldType(i, zcu);
+                        const field_ty = ty.fieldType(i, zcu);
                         elem.* = (try pack.get(field_ty)).toIntern();
                     }
                     return Value.fromInterned(try pt.intern(.{ .aggregate = .{
src/Sema/comptime_ptr_access.zig
@@ -451,7 +451,7 @@ fn loadComptimePtrInner(
                 .@"packed" => break, // let the bitcast logic handle this
                 .@"extern" => for (0..cur_ty.structFieldCount(zcu)) |field_idx| {
                     const start_off = cur_ty.structFieldOffset(field_idx, zcu);
-                    const end_off = start_off + try cur_ty.structFieldType(field_idx, zcu).abiSizeSema(pt);
+                    const end_off = start_off + try cur_ty.fieldType(field_idx, zcu).abiSizeSema(pt);
                     if (cur_offset >= start_off and cur_offset + need_bytes <= end_off) {
                         cur_val = try cur_val.getElem(sema.pt, field_idx);
                         cur_offset -= start_off;
@@ -873,7 +873,7 @@ fn prepareComptimePtrStore(
                 .@"packed" => break, // let the bitcast logic handle this
                 .@"extern" => for (0..cur_ty.structFieldCount(zcu)) |field_idx| {
                     const start_off = cur_ty.structFieldOffset(field_idx, zcu);
-                    const end_off = start_off + try cur_ty.structFieldType(field_idx, zcu).abiSizeSema(pt);
+                    const end_off = start_off + try cur_ty.fieldType(field_idx, zcu).abiSizeSema(pt);
                     if (cur_offset >= start_off and cur_offset + need_bytes <= end_off) {
                         cur_val = try cur_val.elem(pt, sema.arena, field_idx);
                         cur_offset -= start_off;
src/Zcu/PerThread.zig
@@ -3040,38 +3040,6 @@ pub fn intBitsForValue(pt: Zcu.PerThread, val: Value, sign: bool) u16 {
     }
 }
 
-/// Returns 0 if the union is represented with 0 bits at runtime.
-pub fn unionAbiAlignment(pt: Zcu.PerThread, loaded_union: InternPool.LoadedUnionType) InternPool.Alignment {
-    const zcu = pt.zcu;
-    const ip = &zcu.intern_pool;
-    const have_tag = loaded_union.flagsPtr(ip).runtime_tag.hasTag();
-    var max_align: InternPool.Alignment = .none;
-    if (have_tag) max_align = Type.fromInterned(loaded_union.enum_tag_ty).abiAlignment(zcu);
-    for (loaded_union.field_types.get(ip), 0..) |field_ty, field_index| {
-        if (!Type.fromInterned(field_ty).hasRuntimeBits(zcu)) continue;
-
-        const field_align = zcu.unionFieldNormalAlignment(loaded_union, @intCast(field_index));
-        max_align = max_align.max(field_align);
-    }
-    return max_align;
-}
-
-/// Returns the field alignment of a non-packed struct. Asserts the layout is not packed.
-pub fn structFieldAlignment(
-    pt: Zcu.PerThread,
-    explicit_alignment: InternPool.Alignment,
-    field_ty: Type,
-    layout: std.builtin.Type.ContainerLayout,
-) InternPool.Alignment {
-    return field_ty.structFieldAlignmentAdvanced(
-        explicit_alignment,
-        layout,
-        .normal,
-        pt.zcu,
-        {},
-    ) catch unreachable;
-}
-
 /// https://github.com/ziglang/zig/issues/17178 explored storing these bit offsets
 /// into the packed struct InternPool data rather than computing this on the
 /// fly, however it was found to perform worse when measured on real world
src/mutable_value.zig
@@ -223,7 +223,7 @@ pub const MutableValue = union(enum) {
                                     @memset(elems[0..@intCast(len_no_sent)], .{ .interned = undef_elem });
                                 },
                                 .Struct => for (elems[0..@intCast(len_no_sent)], 0..) |*mut_elem, i| {
-                                    const field_ty = ty.structFieldType(i, zcu).toIntern();
+                                    const field_ty = ty.fieldType(i, zcu).toIntern();
                                     mut_elem.* = .{ .interned = try pt.intern(.{ .undef = field_ty }) };
                                 },
                                 else => unreachable,
src/Sema.zig
@@ -4887,7 +4887,7 @@ fn validateStructInit(
         const i: u32 = @intCast(i_usize);
         if (opt_field_ptr.unwrap()) |field_ptr| {
             // Determine whether the value stored to this pointer is comptime-known.
-            const field_ty = struct_ty.structFieldType(i, zcu);
+            const field_ty = struct_ty.fieldType(i, zcu);
             if (try sema.typeHasOnePossibleValue(field_ty)) |opv| {
                 field_values[i] = opv.toIntern();
                 continue;
@@ -4999,7 +4999,7 @@ fn validateStructInit(
         var block_index = first_block_index;
         for (block.instructions.items[first_block_index..]) |cur_inst| {
             while (field_ptr_ref == .none and init_index < instrs.len) : (init_index += 1) {
-                const field_ty = struct_ty.structFieldType(field_indices[init_index], zcu);
+                const field_ty = struct_ty.fieldType(field_indices[init_index], zcu);
                 if (try field_ty.onePossibleValue(pt)) |_| continue;
                 field_ptr_ref = sema.inst_map.get(instrs[init_index]).?;
             }
@@ -8430,7 +8430,7 @@ fn zirArrayInitElemType(sema: *Sema, block: *Block, inst: Zir.Inst.Index) Compil
     try indexable_ty.resolveFields(pt);
     assert(indexable_ty.isIndexable(zcu)); // validated by a previous instruction
     if (indexable_ty.zigTypeTag(zcu) == .Struct) {
-        const elem_type = indexable_ty.structFieldType(@intFromEnum(bin.rhs), zcu);
+        const elem_type = indexable_ty.fieldType(@intFromEnum(bin.rhs), zcu);
         return Air.internedToRef(elem_type.toIntern());
     } else {
         const elem_type = indexable_ty.elemType2(zcu);
@@ -14419,7 +14419,7 @@ fn analyzeTupleCat(
         var runtime_src: ?LazySrcLoc = null;
         var i: u32 = 0;
         while (i < lhs_len) : (i += 1) {
-            types[i] = lhs_ty.structFieldType(i, zcu).toIntern();
+            types[i] = lhs_ty.fieldType(i, zcu).toIntern();
             const default_val = lhs_ty.structFieldDefaultValue(i, zcu);
             values[i] = default_val.toIntern();
             const operand_src = block.src(.{ .array_cat_lhs = .{
@@ -14433,7 +14433,7 @@ fn analyzeTupleCat(
         }
         i = 0;
         while (i < rhs_len) : (i += 1) {
-            types[i + lhs_len] = rhs_ty.structFieldType(i, zcu).toIntern();
+            types[i + lhs_len] = rhs_ty.fieldType(i, zcu).toIntern();
             const default_val = rhs_ty.structFieldDefaultValue(i, zcu);
             values[i + lhs_len] = default_val.toIntern();
             const operand_src = block.src(.{ .array_cat_rhs = .{
@@ -14791,7 +14791,7 @@ fn analyzeTupleMul(
     const opt_runtime_src = rs: {
         var runtime_src: ?LazySrcLoc = null;
         for (0..tuple_len) |i| {
-            types[i] = operand_ty.structFieldType(i, zcu).toIntern();
+            types[i] = operand_ty.fieldType(i, zcu).toIntern();
             values[i] = operand_ty.structFieldDefaultValue(i, zcu).toIntern();
             const operand_src = block.src(.{ .array_cat_lhs = .{
                 .array_cat_offset = src_node,
@@ -18466,13 +18466,7 @@ fn zirTypeInfo(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Ai
                 };
 
                 const alignment = switch (layout) {
-                    .auto, .@"extern" => try Type.unionFieldNormalAlignmentAdvanced(
-                        union_obj,
-                        @intCast(field_index),
-                        .sema,
-                        pt.zcu,
-                        pt.tid,
-                    ),
+                    .auto, .@"extern" => try ty.fieldAlignmentSema(field_index, pt),
                     .@"packed" => .none,
                 };
 
@@ -18691,12 +18685,10 @@ fn zirTypeInfo(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Ai
                     const default_val_ptr = try sema.optRefValue(opt_default_val);
                     const alignment = switch (struct_type.layout) {
                         .@"packed" => .none,
-                        else => try field_ty.structFieldAlignmentAdvanced(
+                        else => try field_ty.structFieldAlignmentSema(
                             struct_type.fieldAlign(ip, field_index),
                             struct_type.layout,
-                            .sema,
-                            pt.zcu,
-                            pt.tid,
+                            pt,
                         ),
                     };
 
@@ -20327,7 +20319,7 @@ fn zirStructInit(
             assert(field_inits[field_index] == .none);
             found_fields[field_index] = item.data.field_type;
             const uncoerced_init = try sema.resolveInst(item.data.init);
-            const field_ty = resolved_ty.structFieldType(field_index, zcu);
+            const field_ty = resolved_ty.fieldType(field_index, zcu);
             field_inits[field_index] = try sema.coerce(block, field_ty, uncoerced_init, field_src);
             if (!is_packed) {
                 try resolved_ty.resolveStructFieldInits(pt);
@@ -20338,7 +20330,7 @@ fn zirStructInit(
                         });
                     };
 
-                    if (!init_val.eql(default_value, resolved_ty.structFieldType(field_index, zcu), zcu)) {
+                    if (!init_val.eql(default_value, resolved_ty.fieldType(field_index, zcu), zcu)) {
                         return sema.failWithInvalidComptimeFieldStore(block, field_src, resolved_ty, field_index);
                     }
                 }
@@ -20799,7 +20791,7 @@ fn zirArrayInit(
         const arg = args[i + 1];
         const resolved_arg = try sema.resolveInst(arg);
         const elem_ty = if (is_tuple)
-            array_ty.structFieldType(i, zcu)
+            array_ty.fieldType(i, zcu)
         else
             array_ty.elemType2(zcu);
         dest.* = try sema.coerce(block, elem_ty, resolved_arg, elem_src);
@@ -20862,7 +20854,7 @@ fn zirArrayInit(
         if (is_tuple) {
             for (resolved_args, 0..) |arg, i| {
                 const elem_ptr_ty = try pt.ptrTypeSema(.{
-                    .child = array_ty.structFieldType(i, zcu).toIntern(),
+                    .child = array_ty.fieldType(i, zcu).toIntern(),
                     .flags = .{ .address_space = target_util.defaultAddressSpace(target, .local) },
                 });
                 const elem_ptr_ty_ref = Air.internedToRef(elem_ptr_ty.toIntern());
@@ -25234,7 +25226,7 @@ fn zirFieldParentPtr(sema: *Sema, block: *Block, extended: Zir.Inst.Extended.Ins
         },
         .packed_offset = parent_ptr_info.packed_offset,
     };
-    const field_ty = parent_ty.structFieldType(field_index, zcu);
+    const field_ty = parent_ty.fieldType(field_index, zcu);
     var actual_field_ptr_info: InternPool.Key.PtrType = .{
         .child = field_ty.toIntern(),
         .flags = .{
@@ -25249,19 +25241,17 @@ fn zirFieldParentPtr(sema: *Sema, block: *Block, extended: Zir.Inst.Extended.Ins
     switch (parent_ty.containerLayout(zcu)) {
         .auto => {
             actual_parent_ptr_info.flags.alignment = actual_field_ptr_info.flags.alignment.minStrict(
-                if (zcu.typeToStruct(parent_ty)) |struct_obj| try field_ty.structFieldAlignmentAdvanced(
-                    struct_obj.fieldAlign(ip, field_index),
-                    struct_obj.layout,
-                    .sema,
-                    pt.zcu,
-                    pt.tid,
-                ) else if (zcu.typeToUnion(parent_ty)) |union_obj|
-                    try Type.unionFieldNormalAlignmentAdvanced(
-                        union_obj,
-                        field_index,
-                        .sema,
-                        pt.zcu,
-                        pt.tid,
+                if (zcu.typeToStruct(parent_ty)) |struct_obj|
+                    try field_ty.structFieldAlignmentSema(
+                        struct_obj.fieldAlign(ip, field_index),
+                        struct_obj.layout,
+                        pt,
+                    )
+                else if (zcu.typeToUnion(parent_ty)) |union_obj|
+                    try field_ty.unionFieldAlignmentSema(
+                        union_obj.fieldAlign(ip, field_index),
+                        union_obj.flagsUnordered(ip).layout,
+                        pt,
                     )
                 else
                     actual_field_ptr_info.flags.alignment,
@@ -28035,14 +28025,14 @@ fn fieldCallBind(
                     }
                     if (field_name.toUnsigned(ip)) |field_index| {
                         if (field_index >= concrete_ty.structFieldCount(zcu)) break :find_field;
-                        return sema.finishFieldCallBind(block, src, ptr_ty, concrete_ty.structFieldType(field_index, zcu), field_index, object_ptr);
+                        return sema.finishFieldCallBind(block, src, ptr_ty, concrete_ty.fieldType(field_index, zcu), field_index, object_ptr);
                     }
                 } else {
                     const max = concrete_ty.structFieldCount(zcu);
                     for (0..max) |i_usize| {
                         const i: u32 = @intCast(i_usize);
                         if (field_name == concrete_ty.structFieldName(i, zcu).unwrap().?) {
-                            return sema.finishFieldCallBind(block, src, ptr_ty, concrete_ty.structFieldType(i, zcu), i, object_ptr);
+                            return sema.finishFieldCallBind(block, src, ptr_ty, concrete_ty.fieldType(i, zcu), i, object_ptr);
                         }
                     }
                 }
@@ -28340,12 +28330,10 @@ fn structFieldPtrByIndex(
             @enumFromInt(@min(@intFromEnum(parent_align), @ctz(field_offset)));
     } else {
         // Our alignment is capped at the field alignment.
-        const field_align = try Type.fromInterned(field_ty).structFieldAlignmentAdvanced(
+        const field_align = try Type.fromInterned(field_ty).structFieldAlignmentSema(
             struct_type.fieldAlign(ip, field_index),
             struct_type.layout,
-            .sema,
-            pt.zcu,
-            pt.tid,
+            pt,
         );
         ptr_ty_data.flags.alignment = if (struct_ptr_ty_info.flags.alignment == .none)
             field_align
@@ -28477,7 +28465,7 @@ fn tupleFieldValByIndex(
 ) CompileError!Air.Inst.Ref {
     const pt = sema.pt;
     const zcu = pt.zcu;
-    const field_ty = tuple_ty.structFieldType(field_index, zcu);
+    const field_ty = tuple_ty.fieldType(field_index, zcu);
 
     if (tuple_ty.structFieldIsComptime(field_index, zcu))
         try tuple_ty.resolveStructFieldInits(pt);
@@ -28538,13 +28526,7 @@ fn unionFieldPtr(
                     union_ptr_info.flags.alignment
                 else
                     try union_ty.abiAlignmentSema(pt);
-                const field_align = try Type.unionFieldNormalAlignmentAdvanced(
-                    union_obj,
-                    field_index,
-                    .sema,
-                    pt.zcu,
-                    pt.tid,
-                );
+                const field_align = try union_ty.fieldAlignmentSema(field_index, pt);
                 break :blk union_align.min(field_align);
             } else union_ptr_info.flags.alignment,
         },
@@ -28921,7 +28903,7 @@ fn tupleFieldPtr(
         });
     }
 
-    const field_ty = tuple_ty.structFieldType(field_index, zcu);
+    const field_ty = tuple_ty.fieldType(field_index, zcu);
     const ptr_field_ty = try pt.ptrTypeSema(.{
         .child = field_ty.toIntern(),
         .flags = .{
@@ -28979,7 +28961,7 @@ fn tupleField(
         });
     }
 
-    const field_ty = tuple_ty.structFieldType(field_index, zcu);
+    const field_ty = tuple_ty.fieldType(field_index, zcu);
 
     if (tuple_ty.structFieldIsComptime(field_index, zcu))
         try tuple_ty.resolveStructFieldInits(pt);
@@ -30615,9 +30597,9 @@ pub fn coerceInMemoryAllowed(
         const field_count = dest_ty.structFieldCount(zcu);
         for (0..field_count) |field_idx| {
             if (dest_ty.structFieldIsComptime(field_idx, zcu) != src_ty.structFieldIsComptime(field_idx, zcu)) break :tuple;
-            if (dest_ty.structFieldAlign(field_idx, zcu) != src_ty.structFieldAlign(field_idx, zcu)) break :tuple;
-            const dest_field_ty = dest_ty.structFieldType(field_idx, zcu);
-            const src_field_ty = src_ty.structFieldType(field_idx, zcu);
+            if (dest_ty.fieldAlignment(field_idx, zcu) != src_ty.fieldAlignment(field_idx, zcu)) break :tuple;
+            const dest_field_ty = dest_ty.fieldType(field_idx, zcu);
+            const src_field_ty = src_ty.fieldType(field_idx, zcu);
             const field = try sema.coerceInMemoryAllowed(block, dest_field_ty, src_field_ty, dest_is_mut, target, dest_src, src_src, null);
             if (field != .ok) break :tuple;
         }
@@ -35073,7 +35055,7 @@ fn resolvePeerTypesInner(
                         peer_field_val.* = null;
                         continue;
                     };
-                    peer_field_ty.* = ty.structFieldType(field_index, zcu);
+                    peer_field_ty.* = ty.fieldType(field_index, zcu);
                     peer_field_val.* = if (opt_val) |val| try val.fieldValue(pt, field_index) else null;
                 }
 
@@ -35095,7 +35077,7 @@ fn resolvePeerTypesInner(
                             // Already-resolved types won't be referenced by the error so it's fine
                             // to leave them undefined.
                             const ty = opt_ty orelse continue;
-                            peer_field_ty.* = ty.structFieldType(field_index, zcu);
+                            peer_field_ty.* = ty.fieldType(field_index, zcu);
                         }
 
                         return .{ .field_error = .{
@@ -35220,9 +35202,9 @@ fn typeIsArrayLike(sema: *Sema, ty: Type) ?ArrayLike {
                 .elem_ty = Type.noreturn,
             };
             if (!ty.isTuple(zcu)) return null;
-            const elem_ty = ty.structFieldType(0, zcu);
+            const elem_ty = ty.fieldType(0, zcu);
             for (1..field_count) |i| {
-                if (!ty.structFieldType(i, zcu).eql(elem_ty, zcu)) {
+                if (!ty.fieldType(i, zcu).eql(elem_ty, zcu)) {
                     return null;
                 }
             }
@@ -35309,12 +35291,10 @@ pub fn resolveStructAlignment(
         const field_ty = Type.fromInterned(struct_type.field_types.get(ip)[i]);
         if (struct_type.fieldIsComptime(ip, i) or try field_ty.comptimeOnlySema(pt))
             continue;
-        const field_align = try field_ty.structFieldAlignmentAdvanced(
+        const field_align = try field_ty.structFieldAlignmentSema(
             struct_type.fieldAlign(ip, i),
             struct_type.layout,
-            .sema,
-            pt.zcu,
-            pt.tid,
+            pt,
         );
         alignment = alignment.maxStrict(field_align);
     }
@@ -35375,12 +35355,10 @@ pub fn resolveStructLayout(sema: *Sema, ty: Type) SemaError!void {
             },
             else => return err,
         };
-        field_align.* = try field_ty.structFieldAlignmentAdvanced(
+        field_align.* = try field_ty.structFieldAlignmentSema(
             struct_type.fieldAlign(ip, i),
             struct_type.layout,
-            .sema,
-            pt.zcu,
-            pt.tid,
+            pt,
         );
         big_align = big_align.maxStrict(field_align.*);
     }
src/Type.zig
@@ -3191,8 +3191,8 @@ pub fn structFieldCount(ty: Type, zcu: *const Zcu) u32 {
     };
 }
 
-/// Supports structs and unions.
-pub fn structFieldType(ty: Type, index: usize, zcu: *const Zcu) Type {
+/// Returns the field type. Supports structs and unions.
+pub fn fieldType(ty: Type, index: usize, zcu: *const Zcu) Type {
     const ip = &zcu.intern_pool;
     return switch (ip.indexToKey(ty.toIntern())) {
         .struct_type => Type.fromInterned(ip.loadStructType(ty.toIntern()).field_types.get(ip)[index]),
@@ -3205,17 +3205,26 @@ pub fn structFieldType(ty: Type, index: usize, zcu: *const Zcu) Type {
     };
 }
 
-pub fn structFieldAlign(ty: Type, index: usize, zcu: *Zcu) Alignment {
-    return ty.structFieldAlignAdvanced(index, .normal, zcu, {}) catch unreachable;
+pub fn fieldAlignment(ty: Type, index: usize, zcu: *Zcu) Alignment {
+    return ty.fieldAlignmentInner(index, .normal, zcu, {}) catch unreachable;
+}
+
+pub fn fieldAlignmentSema(ty: Type, index: usize, pt: Zcu.PerThread) SemaError!Alignment {
+    return try ty.fieldAlignmentInner(index, .sema, pt.zcu, pt.tid);
 }
 
-pub fn structFieldAlignAdvanced(
+/// Returns the field alignment. Supports structs and unions.
+/// If `strat` is `.sema`, may perform type resolution.
+/// Asserts the layout is not packed.
+///
+/// Provide the struct field as the `ty`.
+pub fn fieldAlignmentInner(
     ty: Type,
     index: usize,
     comptime strat: ResolveStrat,
     zcu: *Zcu,
     tid: strat.Tid(),
-) !Alignment {
+) SemaError!Alignment {
     const ip = &zcu.intern_pool;
     switch (ip.indexToKey(ty.toIntern())) {
         .struct_type => {
@@ -3223,13 +3232,7 @@ pub fn structFieldAlignAdvanced(
             assert(struct_type.layout != .@"packed");
             const explicit_align = struct_type.fieldAlign(ip, index);
             const field_ty = Type.fromInterned(struct_type.field_types.get(ip)[index]);
-            return field_ty.structFieldAlignmentAdvanced(
-                explicit_align,
-                struct_type.layout,
-                strat,
-                zcu,
-                tid,
-            );
+            return field_ty.structFieldAlignmentInner(explicit_align, struct_type.layout, strat, zcu, tid);
         },
         .anon_struct_type => |anon_struct| {
             return (try Type.fromInterned(anon_struct.types.get(ip)[index]).abiAlignmentInner(
@@ -3240,28 +3243,62 @@ pub fn structFieldAlignAdvanced(
         },
         .union_type => {
             const union_obj = ip.loadUnionType(ty.toIntern());
-            return unionFieldNormalAlignmentAdvanced(
-                union_obj,
-                @intCast(index),
-                strat,
-                zcu,
-                tid,
-            );
+            const layout = union_obj.flagsUnordered(ip).layout;
+            assert(layout != .@"packed");
+            const explicit_align = union_obj.fieldAlign(ip, index);
+            const field_ty = Type.fromInterned(union_obj.field_types.get(ip)[index]);
+            return field_ty.unionFieldAlignmentInner(explicit_align, layout, strat, zcu, tid);
         },
         else => unreachable,
     }
 }
 
-/// Returns the field alignment of a non-packed struct. Asserts the layout is not packed.
-/// If `strat` is `.sema`, may perform type resolution.
-pub fn structFieldAlignmentAdvanced(
+/// Returns the alignment of a non-packed struct field. Assert the layout is not packed.
+///
+/// Asserts that all resolution needed was done.
+pub fn structFieldAlignment(
     field_ty: Type,
     explicit_alignment: InternPool.Alignment,
     layout: std.builtin.Type.ContainerLayout,
+    zcu: *Zcu,
+) Alignment {
+    return field_ty.structFieldAlignmentInner(
+        explicit_alignment,
+        layout,
+        .normal,
+        zcu,
+        {},
+    ) catch unreachable;
+}
+
+/// Returns the alignment of a non-packed struct field. Assert the layout is not packed.
+/// May do type resolution when needed.
+/// Asserts that all resolution needed was done.
+pub fn structFieldAlignmentSema(
+    field_ty: Type,
+    explicit_alignment: InternPool.Alignment,
+    layout: std.builtin.Type.ContainerLayout,
+    pt: Zcu.PerThread,
+) SemaError!Alignment {
+    return try field_ty.structFieldAlignmentInner(
+        explicit_alignment,
+        layout,
+        .sema,
+        pt.zcu,
+        pt.tid,
+    );
+}
+
+/// Returns the alignment of a non-packed struct field. Asserts the layout is not packed.
+/// If `strat` is `.sema`, may perform type resolution.
+pub fn structFieldAlignmentInner(
+    field_ty: Type,
+    explicit_alignment: Alignment,
+    layout: std.builtin.Type.ContainerLayout,
     comptime strat: Type.ResolveStrat,
     zcu: *Zcu,
     tid: strat.Tid(),
-) Zcu.SemaError!InternPool.Alignment {
+) SemaError!Alignment {
     assert(layout != .@"packed");
     if (explicit_alignment != .none) return explicit_alignment;
     const ty_abi_align = (try field_ty.abiAlignmentInner(
@@ -3281,29 +3318,31 @@ pub fn structFieldAlignmentAdvanced(
     return ty_abi_align;
 }
 
-/// Returns the field alignment of a non-packed union. Asserts the layout is not packed.
-pub fn unionFieldNormalAlignment(
-    loaded_union: InternPool.LoadedUnionType,
-    field_index: u32,
-    zcu: *Zcu,
-) InternPool.Alignment {
-    return unionFieldNormalAlignmentAdvanced(loaded_union, field_index, .normal, zcu, {}) catch unreachable;
+pub fn unionFieldAlignmentSema(
+    field_ty: Type,
+    explicit_alignment: Alignment,
+    layout: std.builtin.Type.ContainerLayout,
+    pt: Zcu.PerThread,
+) SemaError!Alignment {
+    return field_ty.unionFieldAlignmentInner(
+        explicit_alignment,
+        layout,
+        .sema,
+        pt.zcu,
+        pt.tid,
+    );
 }
 
-/// Returns the field alignment of a non-packed union. Asserts the layout is not packed.
-/// If `strat` is `.sema`, may perform type resolution.
-pub fn unionFieldNormalAlignmentAdvanced(
-    loaded_union: InternPool.LoadedUnionType,
-    field_index: u32,
+pub fn unionFieldAlignmentInner(
+    field_ty: Type,
+    explicit_alignment: Alignment,
+    layout: std.builtin.Type.ContainerLayout,
     comptime strat: Type.ResolveStrat,
     zcu: *Zcu,
     tid: strat.Tid(),
-) Zcu.SemaError!InternPool.Alignment {
-    const ip = &zcu.intern_pool;
-    assert(loaded_union.flagsUnordered(ip).layout != .@"packed");
-    const field_align = loaded_union.fieldAlign(ip, field_index);
-    if (field_align != .none) return field_align;
-    const field_ty = Type.fromInterned(loaded_union.field_types.get(ip)[field_index]);
+) SemaError!Alignment {
+    assert(layout != .@"packed");
+    if (explicit_alignment != .none) return explicit_alignment;
     if (field_ty.isNoReturn(zcu)) return .none;
     return (try field_ty.abiAlignmentInner(strat.toLazy(), zcu, tid)).scalar;
 }
@@ -3608,12 +3647,12 @@ pub fn packedStructFieldPtrInfo(struct_ty: Type, parent_ptr_ty: Type, field_idx:
 
     const zcu = pt.zcu;
     const parent_ptr_info = parent_ptr_ty.ptrInfo(zcu);
-    const field_ty = struct_ty.structFieldType(field_idx, zcu);
+    const field_ty = struct_ty.fieldType(field_idx, zcu);
 
     var bit_offset: u16 = 0;
     var running_bits: u16 = 0;
     for (0..struct_ty.structFieldCount(zcu)) |i| {
-        const f_ty = struct_ty.structFieldType(i, zcu);
+        const f_ty = struct_ty.fieldType(i, zcu);
         if (i == field_idx) {
             bit_offset = running_bits;
         }
src/Value.zig
@@ -1414,7 +1414,7 @@ pub fn fieldValue(val: Value, pt: Zcu.PerThread, index: usize) !Value {
     const zcu = pt.zcu;
     return switch (zcu.intern_pool.indexToKey(val.toIntern())) {
         .undef => |ty| Value.fromInterned(try pt.intern(.{
-            .undef = Type.fromInterned(ty).structFieldType(index, zcu).toIntern(),
+            .undef = Type.fromInterned(ty).fieldType(index, zcu).toIntern(),
         })),
         .aggregate => |aggregate| Value.fromInterned(switch (aggregate.storage) {
             .bytes => |bytes| try pt.intern(.{ .int = .{
@@ -3810,9 +3810,9 @@ pub fn ptrField(parent_ptr: Value, field_idx: u32, pt: Zcu.PerThread) !Value {
     // `field_align` may be `.none` to represent the natural alignment of `field_ty`, but is not necessarily.
     const field_ty: Type, const field_align: InternPool.Alignment = switch (aggregate_ty.zigTypeTag(zcu)) {
         .Struct => field: {
-            const field_ty = aggregate_ty.structFieldType(field_idx, zcu);
+            const field_ty = aggregate_ty.fieldType(field_idx, zcu);
             switch (aggregate_ty.containerLayout(zcu)) {
-                .auto => break :field .{ field_ty, try aggregate_ty.structFieldAlignAdvanced(@intCast(field_idx), .sema, zcu, pt.tid) },
+                .auto => break :field .{ field_ty, try aggregate_ty.fieldAlignmentSema(field_idx, pt) },
                 .@"extern" => {
                     // Well-defined layout, so just offset the pointer appropriately.
                     const byte_off = aggregate_ty.structFieldOffset(field_idx, zcu);
@@ -3863,7 +3863,7 @@ pub fn ptrField(parent_ptr: Value, field_idx: u32, pt: Zcu.PerThread) !Value {
             const union_obj = zcu.typeToUnion(aggregate_ty).?;
             const field_ty = Type.fromInterned(union_obj.field_types.get(&zcu.intern_pool)[field_idx]);
             switch (aggregate_ty.containerLayout(zcu)) {
-                .auto => break :field .{ field_ty, try aggregate_ty.structFieldAlignAdvanced(@intCast(field_idx), .sema, zcu, pt.tid) },
+                .auto => break :field .{ field_ty, try aggregate_ty.fieldAlignmentSema(field_idx, pt) },
                 .@"extern" => {
                     // Point to the same address.
                     const result_ty = try pt.ptrTypeSema(info: {
@@ -4198,14 +4198,14 @@ pub fn pointerDerivationAdvanced(ptr_val: Value, arena: Allocator, pt: Zcu.PerTh
             const base_ptr_ty = base_ptr.typeOf(zcu);
             const agg_ty = base_ptr_ty.childType(zcu);
             const field_ty, const field_align = switch (agg_ty.zigTypeTag(zcu)) {
-                .Struct => .{ agg_ty.structFieldType(@intCast(field.index), zcu), try agg_ty.structFieldAlignAdvanced(
-                    @intCast(field.index),
+                .Struct => .{ agg_ty.fieldType(field.index, zcu), try agg_ty.fieldAlignmentInner(
+                    field.index,
                     if (have_sema) .sema else .normal,
                     pt.zcu,
                     if (have_sema) pt.tid else {},
                 ) },
-                .Union => .{ agg_ty.unionFieldTypeByIndex(@intCast(field.index), zcu), try agg_ty.structFieldAlignAdvanced(
-                    @intCast(field.index),
+                .Union => .{ agg_ty.unionFieldTypeByIndex(field.index, zcu), try agg_ty.fieldAlignmentInner(
+                    field.index,
                     if (have_sema) .sema else .normal,
                     pt.zcu,
                     if (have_sema) pt.tid else {},
@@ -4344,7 +4344,7 @@ pub fn pointerDerivationAdvanced(ptr_val: Value, arena: Allocator, pt: Zcu.PerTh
             .Struct => switch (cur_ty.containerLayout(zcu)) {
                 .auto, .@"packed" => break,
                 .@"extern" => for (0..cur_ty.structFieldCount(zcu)) |field_idx| {
-                    const field_ty = cur_ty.structFieldType(field_idx, zcu);
+                    const field_ty = cur_ty.fieldType(field_idx, zcu);
                     const start_off = cur_ty.structFieldOffset(field_idx, zcu);
                     const end_off = start_off + field_ty.abiSize(zcu);
                     if (cur_offset >= start_off and cur_offset + need_bytes <= end_off) {
@@ -4401,7 +4401,7 @@ pub fn resolveLazy(
             .u64, .i64, .big_int => return val,
             .lazy_align, .lazy_size => return pt.intValue(
                 Type.fromInterned(int.ty),
-                (try val.getUnsignedIntInner(.sema, pt.zcu, pt.tid)).?,
+                try val.toUnsignedIntSema(pt),
             ),
         },
         .slice => |slice| {