SmallPtrSet: Inline the part of insert_imp in the small case

Most of the time we only hit the small case, so it is beneficial to pull
it out of the insert_imp() implementation. This improves compile time
at least for non-LTO builds.

Differential Revision: http://reviews.llvm.org/D16619

llvm-svn: 258908

2 files changed, 20 insertions, 17 deletions

diff --git a/llvm/include/llvm/ADT/SmallPtrSet.h b/llvm/include/llvm/ADT/SmallPtrSet.h
index 3d98e8fac43..7e126d4fdd8 100644
--- a/llvm/include/llvm/ADT/SmallPtrSet.h
+++ b/llvm/include/llvm/ADT/SmallPtrSet.h
@@ -102,7 +102,23 @@ protected:
   /// insert_imp - This returns true if the pointer was new to the set, false if
   /// it was already in the set.  This is hidden from the client so that the
   /// derived class can check that the right type of pointer is passed in.
-  std::pair<const void *const *, bool> insert_imp(const void *Ptr);
+  std::pair<const void *const *, bool> insert_imp(const void *Ptr) {
+    if (isSmall()) {
+      // Check to see if it is already in the set.
+      for (const void **APtr = SmallArray, **E = SmallArray+NumElements;
+           APtr != E; ++APtr)
+        if (*APtr == Ptr)
+          return std::make_pair(APtr, false);
+
+      // Nope, there isn't.  If we stay small, just 'pushback' now.
+      if (NumElements < CurArraySize) {
+        SmallArray[NumElements++] = Ptr;
+        return std::make_pair(SmallArray + (NumElements - 1), true);
+      }
+      // Otherwise, hit the big set case, which will call grow.
+    }
+    return insert_imp_big(Ptr);
+  }
 
   /// erase_imp - If the set contains the specified pointer, remove it and
   /// return true, otherwise return false.  This is hidden from the client so
@@ -127,6 +143,8 @@ protected:
 private:
   bool isSmall() const { return CurArray == SmallArray; }
 
+  std::pair<const void *const *, bool> insert_imp_big(const void *Ptr);
+
   const void * const *FindBucketFor(const void *Ptr) const;
   void shrink_and_clear();
 
diff --git a/llvm/lib/Support/SmallPtrSet.cpp b/llvm/lib/Support/SmallPtrSet.cpp
index 358c8e8abbe..e674fc5948c 100644
--- a/llvm/lib/Support/SmallPtrSet.cpp
+++ b/llvm/lib/Support/SmallPtrSet.cpp
@@ -35,22 +35,7 @@ void SmallPtrSetImplBase::shrink_and_clear() {
 }
 
 std::pair<const void *const *, bool>
-SmallPtrSetImplBase::insert_imp(const void *Ptr) {
-  if (isSmall()) {
-    // Check to see if it is already in the set.
-    for (const void **APtr = SmallArray, **E = SmallArray+NumElements;
-         APtr != E; ++APtr)
-      if (*APtr == Ptr)
-        return std::make_pair(APtr, false);
-
-    // Nope, there isn't.  If we stay small, just 'pushback' now.
-    if (NumElements < CurArraySize) {
-      SmallArray[NumElements++] = Ptr;
-      return std::make_pair(SmallArray + (NumElements - 1), true);
-    }
-    // Otherwise, hit the big set case, which will call grow.
-  }
-
+SmallPtrSetImplBase::insert_imp_big(const void *Ptr) {
   if (LLVM_UNLIKELY(NumElements * 4 >= CurArraySize * 3)) {
     // If more than 3/4 of the array is full, grow.
     Grow(CurArraySize < 64 ? 128 : CurArraySize*2);