[dev.typeparams] cmd/compile: factor out implicit/explicit handling

The logic for handling them must keep in sync between reader/writer, so
factoring them out from addBody make it's easier to refer later.

Change-Id: I26447065867d79f4f47cc678a398b9e7bf5d2403
Reviewed-on: https://go-review.googlesource.com/c/go/+/328051
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

1 files changed, 11 insertions, 4 deletions

diff --git a/src/cmd/compile/internal/noder/reader.go b/src/cmd/compile/internal/noder/reader.go
index 18ecbff3cc..803acaa88d 100644
--- a/src/cmd/compile/internal/noder/reader.go
+++ b/src/cmd/compile/internal/noder/reader.go
@@ -789,18 +789,25 @@ var bodyReader = map[*ir.Func]pkgReaderIndex{}
 // constructed.
 var todoBodies []*ir.Func
 
-func (r *reader) addBody(fn *ir.Func) {
-	r.sync(syncAddBody)
+// Keep in sync with writer.implicitTypes
+// Also see comment there for why r.implicits and r.explicits should
+// never both be non-empty.
+func (r *reader) implicitTypes() []*types.Type {
+	r.sync(syncImplicitTypes)
 
-	// See commont in writer.addBody for why r.implicits and r.explicits
-	// should never both be non-empty.
 	implicits := r.implicits
 	if len(implicits) == 0 {
 		implicits = r.explicits
 	} else {
 		assert(len(r.explicits) == 0)
 	}
+	return implicits
+}
+
+func (r *reader) addBody(fn *ir.Func) {
+	r.sync(syncAddBody)
 
+	implicits := r.implicitTypes()
 	pri := pkgReaderIndex{r.p, r.reloc(relocBody), implicits}
 	bodyReader[fn] = pri