// later.
var localPkgReader *pkgReader
-// unified construct the local package's IR from syntax's AST.
+// unified constructs the local package's Internal Representation (IR)
+// from its syntax tree (AST).
//
// The pipeline contains 2 steps:
//
-// 1. Generate package export data "stub".
+// 1. Generate the export data "stub".
//
-// 2. Generate package IR from package export data.
+// 2. Generate the IR from the export data above.
//
// The package data "stub" at step (1) contains everything from the local package,
-// but nothing that have been imported. When we're actually writing out export data
-// to the output files (see writeNewExport function), we run the "linker", which does
-// a few things:
+// but nothing that has been imported. When we're actually writing out export data
+// to the output files (see writeNewExport), we run the "linker", which:
//
-// - Updates compiler extensions data (e.g., inlining cost, escape analysis results).
+// - Updates compiler extensions data (e.g. inlining cost, escape analysis results).
//
// - Handles re-exporting any transitive dependencies.
//
-// - Prunes out any unnecessary details (e.g., non-inlineable functions, because any
+// - Prunes out any unnecessary details (e.g. non-inlineable functions, because any
// downstream importers only care about inlinable functions).
//
-// The source files are typechecked twice, once before writing export data
-// using types2 checker, once after read export data using gc/typecheck.
-// This duplication of work will go away once we always use types2 checker,
-// we can remove the gc/typecheck pass. The reason it is still here:
+// The source files are typechecked twice: once before writing the export data
+// using types2, and again after reading the export data using gc/typecheck.
+// The duplication of work will go away once we only use the types2 type checker,
+// removing the gc/typecheck step. For now, it is kept because:
//
-// - It reduces engineering costs in maintaining a fork of typecheck
-// (e.g., no need to backport fixes like CL 327651).
+// - It reduces the engineering costs in maintaining a fork of typecheck
+// (e.g. no need to backport fixes like CL 327651).
//
// - It makes it easier to pass toolstash -cmp.
//
-// - Historically, we would always re-run the typechecker after import, even though
-// we know the imported data is valid. It's not ideal, but also not causing any
-// problem either.
+// - Historically, we would always re-run the typechecker after importing a package,
+// even though we know the imported data is valid. It's not ideal, but it's
+// not causing any problems either.
//
-// - There's still transformation that being done during gc/typecheck, like rewriting
-// multi-valued function call, or transform ir.OINDEX -> ir.OINDEXMAP.
+// - gc/typecheck is still in charge of some transformations, such as rewriting
+// multi-valued function calls or transforming ir.OINDEX to ir.OINDEXMAP.
//
-// Using syntax+types2 tree, which already has a complete representation of generics,
-// the unified IR has the full typed AST for doing introspection during step (1).
-// In other words, we have all necessary information to build the generic IR form
+// Using the syntax tree with types2, which has a complete representation of generics,
+// the unified IR has the full typed AST needed for introspection during step (1).
+// In other words, we have all the necessary information to build the generic IR form
// (see writer.captureVars for an example).
func unified(noders []*noder) {
inline.NewInline = InlineCall