Zcu: extract permanent state from File

Primarily, this commit removes 2 fields from File, relying on the data
being stored in the `files` field, with the key as the path digest, and
the value as the struct decl corresponding to the File. This table is
serialized into the compiler state that survives between incremental
updates.

Meanwhile, the File struct remains ephemeral data that can be
reconstructed the first time it is needed by the compiler process, as
well as operated on by independent worker threads.

A key outcome of this commit is that there is now a stable index that
can be used to refer to a File. This will be needed when serializing
error messages to survive incremental compilation updates.

1 files changed, 7 insertions, 15 deletions

diff --git a/src/main.zig b/src/main.zig
index d9084686c8..3ba1276abf 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -27,8 +27,6 @@ const Cache = std.Build.Cache;
 const target_util = @import("target.zig");
 const crash_report = @import("crash_report.zig");
 const Zcu = @import("Zcu.zig");
-/// Deprecated.
-const Module = Zcu;
 const AstGen = std.zig.AstGen;
 const mingw = @import("mingw.zig");
 const Server = std.zig.Server;
@@ -919,7 +917,7 @@ fn buildOutputType(
     var contains_res_file: bool = false;
     var reference_trace: ?u32 = null;
     var pdb_out_path: ?[]const u8 = null;
-    var error_limit: ?Module.ErrorInt = null;
+    var error_limit: ?Zcu.ErrorInt = null;
     // These are before resolving sysroot.
     var extra_cflags: std.ArrayListUnmanaged([]const u8) = .{};
     var extra_rcflags: std.ArrayListUnmanaged([]const u8) = .{};
@@ -1107,7 +1105,7 @@ fn buildOutputType(
                         );
                     } else if (mem.eql(u8, arg, "--error-limit")) {
                         const next_arg = args_iter.nextOrFatal();
-                        error_limit = std.fmt.parseUnsigned(Module.ErrorInt, next_arg, 0) catch |err| {
+                        error_limit = std.fmt.parseUnsigned(Zcu.ErrorInt, next_arg, 0) catch |err| {
                             fatal("unable to parse error limit '{s}': {s}", .{ next_arg, @errorName(err) });
                         };
                     } else if (mem.eql(u8, arg, "-cflags")) {
@@ -5956,7 +5954,7 @@ fn cmdAstCheck(
         }
     }
 
-    var file: Module.File = .{
+    var file: Zcu.File = .{
         .status = .never_loaded,
         .source_loaded = false,
         .tree_loaded = false,
@@ -5967,8 +5965,6 @@ fn cmdAstCheck(
         .tree = undefined,
         .zir = undefined,
         .mod = undefined,
-        .root_decl = .none,
-        .path_digest = undefined,
     };
     if (zig_source_file) |file_name| {
         var f = fs.cwd().openFile(file_name, .{}) catch |err| {
@@ -6275,7 +6271,7 @@ fn cmdDumpZir(
     };
     defer f.close();
 
-    var file: Module.File = .{
+    var file: Zcu.File = .{
         .status = .never_loaded,
         .source_loaded = false,
         .tree_loaded = false,
@@ -6284,10 +6280,8 @@ fn cmdDumpZir(
         .source = undefined,
         .stat = undefined,
         .tree = undefined,
-        .zir = try Module.loadZirCache(gpa, f),
+        .zir = try Zcu.loadZirCache(gpa, f),
         .mod = undefined,
-        .root_decl = .none,
-        .path_digest = undefined,
     };
     defer file.zir.deinit(gpa);
 
@@ -6342,7 +6336,7 @@ fn cmdChangelist(
     if (stat.size > std.zig.max_src_size)
         return error.FileTooBig;
 
-    var file: Module.File = .{
+    var file: Zcu.File = .{
         .status = .never_loaded,
         .source_loaded = false,
         .tree_loaded = false,
@@ -6357,8 +6351,6 @@ fn cmdChangelist(
         .tree = undefined,
         .zir = undefined,
         .mod = undefined,
-        .root_decl = .none,
-        .path_digest = undefined,
     };
 
     file.mod = try Package.Module.createLimited(arena, .{
@@ -6431,7 +6423,7 @@ fn cmdChangelist(
     var inst_map: std.AutoHashMapUnmanaged(Zir.Inst.Index, Zir.Inst.Index) = .{};
     defer inst_map.deinit(gpa);
 
-    try Module.mapOldZirToNew(gpa, old_zir, file.zir, &inst_map);
+    try Zcu.mapOldZirToNew(gpa, old_zir, file.zir, &inst_map);
 
     var bw = io.bufferedWriter(io.getStdOut().writer());
     const stdout = bw.writer();