Use an IndexedMap instead of a DenseMap for the live-out cache.

This speeds up updateSSA() so it only accounts for 5% of the live range
splitting time.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126972 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 9 insertions, 0 deletions

diff --git a/include/llvm/CodeGen/MachineBasicBlock.h b/include/llvm/CodeGen/MachineBasicBlock.h
index 1785451c7e..1906093388 100644
--- a/include/llvm/CodeGen/MachineBasicBlock.h
+++ b/include/llvm/CodeGen/MachineBasicBlock.h
@@ -16,6 +16,7 @@
 
 #include "llvm/CodeGen/MachineInstr.h"
 #include "llvm/ADT/GraphTraits.h"
+#include <functional>
 
 namespace llvm {
 
@@ -411,6 +412,14 @@ raw_ostream& operator<<(raw_ostream &OS, const MachineBasicBlock &MBB);
 
 void WriteAsOperand(raw_ostream &, const MachineBasicBlock*, bool t);
 
+// This is useful when building IndexedMaps keyed on basic block pointers.
+struct MBB2NumberFunctor :
+  public std::unary_function<const MachineBasicBlock*, unsigned> {
+  unsigned operator()(const MachineBasicBlock *MBB) const {
+    return MBB->getNumber();
+  }
+};
+
 //===--------------------------------------------------------------------===//
 // GraphTraits specializations for machine basic block graphs (machine-CFGs)
 //===--------------------------------------------------------------------===//