Add SlotIndexes::getMBBRange() to get the range of a basic block in a single

lookup.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121893 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 10 insertions, 6 deletions

diff --git a/include/llvm/CodeGen/SlotIndexes.h b/include/llvm/CodeGen/SlotIndexes.h
index fd965fc290..312ce0380f 100644
--- a/include/llvm/CodeGen/SlotIndexes.h
+++ b/include/llvm/CodeGen/SlotIndexes.h
@@ -545,18 +545,22 @@ namespace llvm {
       return nextNonNull;
     }
 
-    /// Returns the first index in the given basic block.
-    SlotIndex getMBBStartIdx(const MachineBasicBlock *mbb) const {
+    /// Return the (start,end) range of the given basic block.
+    const std::pair<SlotIndex, SlotIndex> &
+    getMBBRange(const MachineBasicBlock *mbb) const {
       MBB2IdxMap::const_iterator itr = mbb2IdxMap.find(mbb);
       assert(itr != mbb2IdxMap.end() && "MBB not found in maps.");
-      return itr->second.first;
+      return itr->second;
+    }
+
+    /// Returns the first index in the given basic block.
+    SlotIndex getMBBStartIdx(const MachineBasicBlock *mbb) const {
+      return getMBBRange(mbb).first;
     }
 
     /// Returns the last index in the given basic block.
     SlotIndex getMBBEndIdx(const MachineBasicBlock *mbb) const {
-      MBB2IdxMap::const_iterator itr = mbb2IdxMap.find(mbb);
-      assert(itr != mbb2IdxMap.end() && "MBB not found in maps.");
-      return itr->second.second;
+      return getMBBRange(mbb).second;
     }
 
     /// Returns the basic block which the given index falls in.