commit 00570224891da83c5066b8d135232f96786dbd56
author Jakob Stoklund Olesen <stoklund@2pi.dk> Mon May 14 15:46:27 2012 +0000
committer Jakob Stoklund Olesen <stoklund@2pi.dk> Mon May 14 15:46:27 2012 +0000
tree e3237abe14c6489a79e1602206bfc34a06ac89a2
parent 9e10d773e155fcd9fba9c3e1a7d2e49f31c42731

Remove the expensive BitVector::operator~().

Returning a temporary BitVector is very expensive. If you must, create
the temporary explicitly: Use BitVector(A).flip() instead of ~A.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156768 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/ADT/BitVector.h

diff --git a/include/llvm/ADT/BitVector.h b/include/llvm/ADT/BitVector.h
index 23aad6e..3cbaf1a 100644
--- a/include/llvm/ADT/BitVector.h
+++ b/include/llvm/ADT/BitVector.h
@@ -251,11 +251,6 @@
     return *this;
   }
 
-  // No argument flip.
-  BitVector operator~() const {
-    return BitVector(*this).flip();
-  }
-
   // Indexing.
   reference operator[](unsigned Idx) {
     assert (Idx < Size && "Out-of-bounds Bit access.");

unittests/ADT/BitVectorTest.cpp

diff --git a/unittests/ADT/BitVectorTest.cpp b/unittests/ADT/BitVectorTest.cpp
index 24ce3dd..62aadf6 100644
--- a/unittests/ADT/BitVectorTest.cpp
+++ b/unittests/ADT/BitVectorTest.cpp
@@ -42,7 +42,8 @@
   EXPECT_FALSE(Vec.none());
   EXPECT_FALSE(Vec.empty());
 
-  BitVector Inv = ~Vec;
+  BitVector Inv = Vec;
+  Inv.flip();
   EXPECT_EQ(6U, Inv.count());
   EXPECT_EQ(11U, Inv.size());
   EXPECT_TRUE(Inv.any());
@@ -52,7 +53,7 @@
 
   EXPECT_FALSE(Inv == Vec);
   EXPECT_TRUE(Inv != Vec);
-  Vec = ~Vec;
+  Vec.flip();
   EXPECT_TRUE(Inv == Vec);
   EXPECT_FALSE(Inv != Vec);
 
@@ -131,7 +132,7 @@
   EXPECT_TRUE(Vec.none());
   EXPECT_FALSE(Vec.empty());
 
-  Inv = ~BitVector();
+  Inv = BitVector().flip();
   EXPECT_EQ(0U, Inv.count());
   EXPECT_EQ(0U, Inv.size());
   EXPECT_FALSE(Inv.any());