internal/gocore: fix funcdata offset

CL 354011 remove unnecessary funcdata alignment. Update references.

For golang/go#57447.

Change-Id: I14414ea4be048c3bb8bbde711c10474f7f0515e4
Reviewed-on: https://go-review.googlesource.com/c/debug/+/589035
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>

internal/gocore/module.go

diff --git a/internal/gocore/module.go b/internal/gocore/module.go
index 925138b..9429a8d 100644
--- a/internal/gocore/module.go
+++ b/internal/gocore/module.go
@@ -126,7 +126,12 @@
 		f.pcdata = append(f.pcdata, r.p.proc.ReadInt32(a))
 		a = a.Add(4)
 	}
-	a = a.Align(r.p.proc.PtrSize())
+
+	is118OrGreater := m.r.HasField("gofunc")
+	if !is118OrGreater {
+		// Since 1.18, funcdata no longer needs to be aligned.
+		a = a.Align(r.p.proc.PtrSize())
+	}
 
 	if nfd.typ.Size == 1 { // go 1.12 and beyond, this is a uint8
 		n = uint32(nfd.Uint8())
@@ -134,7 +139,7 @@
 		n = uint32(nfd.Int32())
 	}
 	for i := uint32(0); i < n; i++ {
-		if m.r.HasField("gofunc") {
+		if is118OrGreater {
 			// Since 1.18, funcdata contains offsets from go.func.*.
 			off := r.p.proc.ReadUint32(a)
 			if off == ^uint32(0) {