cmd/vendor/github.com/google/pprof: refresh from upstream

Updating to commit 0e0e5b7254e076a62326ab7305ba49e8515f0c91
from github.com/google/pprof

Recent modifications to the vendored pprof, such as skipping
TestWebInterface to avoid starting a web browser, have all been fixed
upstream.

Change-Id: I72e11108c438e1573bf2f9216e76d157378e8d45
Reviewed-on: https://go-review.googlesource.com/93375
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

1 files changed, 29 insertions, 5 deletions

diff --git a/src/cmd/vendor/github.com/google/pprof/internal/binutils/disasm.go b/src/cmd/vendor/github.com/google/pprof/internal/binutils/disasm.go
index 1a3b6f8d6a..28c89aa163 100644
--- a/src/cmd/vendor/github.com/google/pprof/internal/binutils/disasm.go
+++ b/src/cmd/vendor/github.com/google/pprof/internal/binutils/disasm.go
@@ -34,24 +34,48 @@ var (
 func findSymbols(syms []byte, file string, r *regexp.Regexp, address uint64) ([]*plugin.Sym, error) {
 	// Collect all symbols from the nm output, grouping names mapped to
 	// the same address into a single symbol.
+
+	// The symbols to return.
 	var symbols []*plugin.Sym
+
+	// The current group of symbol names, and the address they are all at.
 	names, start := []string{}, uint64(0)
+
 	buf := bytes.NewBuffer(syms)
-	for symAddr, name, err := nextSymbol(buf); err == nil; symAddr, name, err = nextSymbol(buf) {
+
+	for {
+		symAddr, name, err := nextSymbol(buf)
+		if err == io.EOF {
+			// Done. If there was an unfinished group, append it.
+			if len(names) != 0 {
+				if match := matchSymbol(names, start, symAddr-1, r, address); match != nil {
+					symbols = append(symbols, &plugin.Sym{Name: match, File: file, Start: start, End: symAddr - 1})
+				}
+			}
+
+			// And return the symbols.
+			return symbols, nil
+		}
+
 		if err != nil {
+			// There was some kind of serious error reading nm's output.
 			return nil, err
 		}
-		if start == symAddr {
+
+		// If this symbol is at the same address as the current group, add it to the group.
+		if symAddr == start {
 			names = append(names, name)
 			continue
 		}
+
+		// Otherwise append the current group to the list of symbols.
 		if match := matchSymbol(names, start, symAddr-1, r, address); match != nil {
 			symbols = append(symbols, &plugin.Sym{Name: match, File: file, Start: start, End: symAddr - 1})
 		}
+
+		// And start a new group.
 		names, start = []string{name}, symAddr
 	}
-
-	return symbols, nil
 }
 
 // matchSymbol checks if a symbol is to be selected by checking its
@@ -62,7 +86,7 @@ func matchSymbol(names []string, start, end uint64, r *regexp.Regexp, address ui
 		return names
 	}
 	for _, name := range names {
-		if r.MatchString(name) {
+		if r == nil || r.MatchString(name) {
 			return []string{name}
 		}