[PATCH] Implement NaCl sandboxing of function calls

[Mark Seaborn]

  LGTM, thanks


================
Comment at: lib/Target/Mips/MCTargetDesc/MipsNaClELFStreamer.cpp:135
@@ -110,3 +134,3 @@
     bool IsSPFirstOperand = isStackPointerFirstOperand(Inst);
     if (IsMemAccess || IsSPFirstOperand) {
       bool MaskBefore = (IsMemAccess
----------------
You could check PendingCall here (and for isIndirectJump above and isCall below) and report_fatal_error if it's set, since this would be an invalid instruction in the branch delay slot.  Otherwise you might silently emit a mismatched bundle lock/unlock.

================
Comment at: lib/Target/Mips/MCTargetDesc/MipsNaClELFStreamer.cpp:152
@@ +151,3 @@
+      // Start the sandboxing sequence by emitting call.
+      EmitBundleLock(true);
+      if (IsIndirectCall) {
----------------
Nice simplification from the previous version.


http://llvm-reviews.chandlerc.com/D3032