cmd/internal/goobj: update to support go19ld

Updates the disassembler to support the same object file version used
by the assembler and linker.

Related #14782.

Change-Id: I4cd7560c4e4e1350cfb27ca9cbe0fde25fe693cc
Reviewed-on: https://go-review.googlesource.com/37797
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

src/cmd/internal/goobj/read.go

@@ -198,9 +198,11 @@ type Func struct {
 	PCSP     Data       // PC → SP offset map
 	PCFile   Data       // PC → file number map (index into File)
 	PCLine   Data       // PC → line number map
+	PCInline Data       // PC → inline tree index map
 	PCData   []Data     // PC → runtime support data map
 	FuncData []FuncData // non-PC-specific runtime support data
 	File     []string   // paths indexed by PCFile
+	InlTree  []InlinedCall
 }
 
 // TODO: Add PCData []byte and PCDataIter (similar to liblink).
@@ -211,6 +213,15 @@ type FuncData struct {
 	Offset int64 // offset into symbol for funcdata pointer
 }
 
+// An InlinedCall is a node in an InlTree.
+// See cmd/internal/obj.InlTree for details.
+type InlinedCall struct {
+	Parent int
+	File   string
+	Line   int
+	Func   SymID
+}
+
 // A Package is a parsed Go object file or archive defining a Go package.
 type Package struct {
 	ImportPath string   // import path denoting this package
@@ -583,7 +594,7 @@ func (r *objReader) parseObject(prefix []byte) error {
 	// TODO: extract OS + build ID if/when we need it
 
 	r.readFull(r.tmp[:8])
-	if !bytes.Equal(r.tmp[:8], []byte("\x00\x00go17ld")) {
+	if !bytes.Equal(r.tmp[:8], []byte("\x00\x00go19ld")) {
 		return r.error(errCorruptObject)
 	}
 
@@ -671,6 +682,7 @@ func (r *objReader) parseObject(prefix []byte) error {
 			f.PCSP = r.readData()
 			f.PCFile = r.readData()
 			f.PCLine = r.readData()
+			f.PCInline = r.readData()
 			f.PCData = make([]Data, r.readInt())
 			for i := range f.PCData {
 				f.PCData[i] = r.readData()
@@ -686,11 +698,18 @@ func (r *objReader) parseObject(prefix []byte) error {
 			for i := range f.File {
 				f.File[i] = r.readSymID().Name
 			}
+			f.InlTree = make([]InlinedCall, r.readInt())
+			for i := range f.InlTree {
+				f.InlTree[i].Parent = r.readInt()
+				f.InlTree[i].File = r.readSymID().Name
+				f.InlTree[i].Line = r.readInt()
+				f.InlTree[i].Func = r.readSymID()
+			}
 		}
 	}
 
 	r.readFull(r.tmp[:7])
-	if !bytes.Equal(r.tmp[:7], []byte("\xffgo17ld")) {
+	if !bytes.Equal(r.tmp[:7], []byte("\xffgo19ld")) {
 		return r.error(errCorruptObject)
 	}