Clean out per-function data after the machine code verifier is done with it.

Also don't dereference old pointers after they have been deleted causing
random crashes when enabling the machine code verifier.

Ahem...

I have not included a test case for the crash. It hapened when enabling the
verifier on CodeGen/X86/2009-08-06-branchfolder-crash.ll.

The crash depends on an MBB being allocated at the same address as a
previously deleted MBB. I don't think that can be reproduced reliably.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78472 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/MachineVerifier.cpp b/lib/CodeGen/MachineVerifier.cpp
index e6ed18057cf5a8b120cf7c67195d2b1589fe3ae6..0b9127fd4a521fc719c45ea28b7f063c143a7a2e 100644 (file)
--- a/lib/CodeGen/MachineVerifier.cpp
+++ b/lib/CodeGen/MachineVerifier.cpp
@@ -220,6 +220,14 @@ MachineVerifier::runOnMachineFunction(MachineFunction &MF)
     llvm_report_error(Msg.str());
   }
 
+  // Clean up.
+  regsLive.clear();
+  regsDefined.clear();
+  regsDead.clear();
+  regsKilled.clear();
+  regsLiveInButUnused.clear();
+  MBBInfoMap.clear();
+
   return false;                 // no changes
 }