[PATCH] Support using sample profiles with partial debug info.

[David Blaikie]

Some optional tidbits, but otherwise fine.

================
Comment at: lib/Transforms/Scalar/SampleProfile.cpp:646
@@ +645,3 @@
+      DebugLoc DLoc = Inst.getDebugLoc();
+      if (!DLoc.isUnknown()) {
+        const MDNode *Scope = DLoc.getScopeNode(Ctx);
----------------
usually we do this with an early continue to avoid extra indentation

  if (DLoc.isKnown())
    continue;
  /* more stuff */

& yeah, no worries about the range-for loops, a single cleanup would be fine

================
Comment at: lib/Transforms/Scalar/SampleProfile.cpp:675
@@ -658,1 +674,3 @@
+  // about the missed opportunity.
   F.getContext().diagnose(DiagnosticInfoSampleProfile(
+      "No debug information found in function " + F.getName() +
----------------
Separating the change in text and error->warning (& the subsequent test changes) into a separate commit would be nice.

http://reviews.llvm.org/D5887