From 583eeaae509a01cc50955c4174044b9dac539ff6 Mon Sep 17 00:00:00 2001
From: Cherry Mui <cherryyz@google.com>
Date: Mon, 27 Sep 2021 15:55:53 -0400
Subject: [PATCH] cmd/internal/objfile: use aux symbol for pcdata references

Pcdata are now separate aux symbols. Read them from aux, instead
of using funcinfo.

Change-Id: Ib3e4b5cff1e3329d0600504a8829a969a9c9f517
Reviewed-on: https://go-review.googlesource.com/c/go/+/352612
Trust: Cherry Mui <cherryyz@google.com>
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
---
 src/cmd/internal/goobj/objfile.go |  2 ++
 src/cmd/internal/objfile/goobj.go | 25 ++++++++++---------------
 2 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/src/cmd/internal/goobj/objfile.go b/src/cmd/internal/goobj/objfile.go
index fc6dbb8af6e..2c44696f84c 100644
--- a/src/cmd/internal/goobj/objfile.go
+++ b/src/cmd/internal/goobj/objfile.go
@@ -357,6 +357,8 @@ type SymRef struct {
 	SymIdx uint32
 }
 
+func (s SymRef) IsZero() bool { return s == SymRef{} }
+
 // Hash64
 type Hash64Type [Hash64Size]byte
 
diff --git a/src/cmd/internal/objfile/goobj.go b/src/cmd/internal/objfile/goobj.go
index dd21d223511..24d2d0bb5c7 100644
--- a/src/cmd/internal/objfile/goobj.go
+++ b/src/cmd/internal/objfile/goobj.go
@@ -250,26 +250,21 @@ func (f *goobjFile) PCToLine(pc uint64) (string, int, *gosym.Func) {
 		if pc < addr || pc >= addr+uint64(osym.Siz()) {
 			continue
 		}
-		isym := ^uint32(0)
-		auxs := r.Auxs(i)
-		for j := range auxs {
-			a := &auxs[j]
-			if a.Type() != goobj.AuxFuncInfo {
-				continue
+		var pcfileSym, pclineSym goobj.SymRef
+		for _, a := range r.Auxs(i) {
+			switch a.Type() {
+			case goobj.AuxPcfile:
+				pcfileSym = a.Sym()
+			case goobj.AuxPcline:
+				pclineSym = a.Sym()
 			}
-			if a.Sym().PkgIdx != goobj.PkgIdxSelf {
-				panic("funcinfo symbol not defined in current package")
-			}
-			isym = a.Sym().SymIdx
 		}
-		if isym == ^uint32(0) {
+		if pcfileSym.IsZero() || pclineSym.IsZero() {
 			continue
 		}
-		b := r.BytesAt(r.DataOff(isym), r.DataSize(isym))
-		var info *goobj.FuncInfo
-		pcline := getSymData(info.ReadPcline(b))
+		pcline := getSymData(pclineSym)
 		line := int(pcValue(pcline, pc-addr, f.arch))
-		pcfile := getSymData(info.ReadPcfile(b))
+		pcfile := getSymData(pcfileSym)
 		fileID := pcValue(pcfile, pc-addr, f.arch)
 		fileName := r.File(int(fileID))
 		// Note: we provide only the name in the Func structure.