Improve ExtractSymbols (pprof).

Iterated downward through both libraries and PCs.  This allows PCs
to resolve even when library address ranges overlap.

1 files changed, 4 insertions, 11 deletions

diff --git a/jemalloc/bin/pprof b/jemalloc/bin/pprof
index 73d35dd..e42d3b2 100755
--- a/jemalloc/bin/pprof
+++ b/jemalloc/bin/pprof
@@ -3682,16 +3682,9 @@ sub ExtractSymbols {
 
   # Map each PC value to the containing library
   my @pcs = (sort { $a cmp $b } keys(%{$pcset}));
-  my @slibs = (sort {$a->[1] cmp $b->[1]} @{$libs});
-  my $bin = shift(@slibs);
-  if ($bin->[1] == 0) {
-    # Move binary to end (starts at address 0).
-    push(@slibs, $bin);
-  } else {
-    unshift(@slibs, $bin);
-  }
-  my $pc = shift(@pcs);
-  foreach my $lib (@slibs) {
+  my $pc = pop(@pcs);
+
+  foreach my $lib (reverse sort {$a->[1] cmp $b->[1]} @{$libs}) {
     my $libname = $lib->[0];
     my $start = $lib->[1];
     my $finish = $lib->[2];
@@ -3701,7 +3694,7 @@ sub ExtractSymbols {
     my $contained = [];
     while (($pc ge $start) && ($pc le $finish)) {
       push(@{$contained}, $pc);
-      $pc = shift(@pcs);
+      $pc = pop(@pcs);
       if (!defined $pc) {
         last;
       }