cmd/addr2line, cmd/objdump: fix on amd64 Plan 9

Fix virtual address of the start of the text segment
on amd64 Plan 9.

This issue has been partially fixed in cmd/add2line,
as part of CL 106460044, but we forgot to report the
change to cmd/objdump.

In the meantime, we also fixed the textStart address
in both cmd/add2line and cmd/objdump.

LGTM=aram, ality, mischief
R=rsc, mischief, aram, ality
CC=golang-codereviews, jas
https://golang.org/cl/117920043

diff --git a/src/cmd/addr2line/main.go b/src/cmd/addr2line/main.go
index c6e4563db75f31bf79b3b456234d960cdd00ef72..3802f764f9195176c85513c5c8bf0bb55ff3c4af 100644 (file)
--- a/src/cmd/addr2line/main.go
+++ b/src/cmd/addr2line/main.go
@@ -161,11 +161,7 @@ func loadTables(f *os.File) (textStart uint64, symtab, pclntab []byte, err error
        }
 
        if obj, err := plan9obj.NewFile(f); err == nil {
-               sym, err := findPlan9Symbol(obj, "text")
-               if err != nil {
-                       return 0, nil, nil, err
-               }
-               textStart = sym.Value
+               textStart = obj.LoadAddress + obj.HdrSize
                if pclntab, err = loadPlan9Table(obj, "pclntab", "epclntab"); err != nil {
                        return 0, nil, nil, err
                }
@@ -245,5 +241,6 @@ func loadPlan9Table(f *plan9obj.File, sname, ename string) ([]byte, error) {
        if err != nil {
                return nil, err
        }
-       return data[ssym.Value-(f.LoadAddress+f.HdrSize) : esym.Value-(f.LoadAddress+f.HdrSize)], nil
+       textStart := f.LoadAddress + f.HdrSize
+       return data[ssym.Value-textStart : esym.Value-textStart], nil
 }

diff --git a/src/cmd/objdump/main.go b/src/cmd/objdump/main.go
index 137776f47a3dd59458711ae05d2d56dcb4fefcaa..9922dcc023002821a71743d85ae672004821feb1 100644 (file)
--- a/src/cmd/objdump/main.go
+++ b/src/cmd/objdump/main.go
@@ -365,11 +365,7 @@ func loadTables(f *os.File) (textStart uint64, textData, symtab, pclntab []byte,
        }
 
        if obj, err := plan9obj.NewFile(f); err == nil {
-               sym, err := findPlan9Symbol(obj, "text")
-               if err != nil {
-                       return 0, nil, nil, nil, err
-               }
-               textStart = sym.Value
+               textStart = obj.LoadAddress + obj.HdrSize
                if sect := obj.Section("text"); sect != nil {
                        textData, _ = sect.Data()
                }
@@ -444,10 +440,6 @@ func loadPlan9Table(f *plan9obj.File, sname, ename string) ([]byte, error) {
        if err != nil {
                return nil, err
        }
-       text, err := findPlan9Symbol(f, "text")
-       if err != nil {
-               return nil, err
-       }
        sect := f.Section("text")
        if sect == nil {
                return nil, err
@@ -456,7 +448,8 @@ func loadPlan9Table(f *plan9obj.File, sname, ename string) ([]byte, error) {
        if err != nil {
                return nil, err
        }
-       return data[ssym.Value-text.Value : esym.Value-text.Value], nil
+       textStart := f.LoadAddress + f.HdrSize
+       return data[ssym.Value-textStart : esym.Value-textStart], nil
 }
 
 // TODO(rsc): This code is taken from cmd/nm. Arrange some way to share the code.