Fix allocations of SmallVector and SmallPtrSet so they are more prone to

being power-of-two sized.

llvm-svn: 178332

1 files changed, 55 insertions, 0 deletions

diff --git a/llvm/unittests/ADT/SmallPtrSetTest.cpp b/llvm/unittests/ADT/SmallPtrSetTest.cpp
index 9114875e003..f85d7c941eb 100644
--- a/llvm/unittests/ADT/SmallPtrSetTest.cpp
+++ b/llvm/unittests/ADT/SmallPtrSetTest.cpp
@@ -17,6 +17,61 @@
 using namespace llvm;
 
 // SmallPtrSet swapping test.
+TEST(SmallPtrSetTest, GrowthTest) {
+  int i;
+  int buf[8];
+  for(i=0; i<8; ++i) buf[i]=0;
+
+
+  SmallPtrSet<int *, 4> s;
+  typedef SmallPtrSet<int *, 4>::iterator iter;
+  
+  s.insert(&buf[0]);
+  s.insert(&buf[1]);
+  s.insert(&buf[2]);
+  s.insert(&buf[3]);
+  EXPECT_EQ(4U, s.size());
+
+  i = 0;
+  for(iter I=s.begin(), E=s.end(); I!=E; ++I, ++i)
+      (**I)++;
+  EXPECT_EQ(4, i);
+  for(i=0; i<8; ++i)
+      EXPECT_EQ(i<4?1:0,buf[i]);
+
+  s.insert(&buf[4]);
+  s.insert(&buf[5]);
+  s.insert(&buf[6]);
+  s.insert(&buf[7]);
+
+  i = 0;
+  for(iter I=s.begin(), E=s.end(); I!=E; ++I, ++i)
+      (**I)++;
+  EXPECT_EQ(8, i);
+  s.erase(&buf[4]);
+  s.erase(&buf[5]);
+  s.erase(&buf[6]);
+  s.erase(&buf[7]);
+  EXPECT_EQ(4U, s.size());
+
+  i = 0;
+  for(iter I=s.begin(), E=s.end(); I!=E; ++I, ++i)
+      (**I)++;
+  EXPECT_EQ(4, i);
+  for(i=0; i<8; ++i)
+      EXPECT_EQ(i<4?3:1,buf[i]);
+
+  s.clear();
+  for(i=0; i<8; ++i) buf[i]=0;
+  for(i=0; i<128; ++i) s.insert(&buf[i%8]); // test repeated entires
+  EXPECT_EQ(8U, s.size());
+  for(iter I=s.begin(), E=s.end(); I!=E; ++I, ++i)
+      (**I)++;
+  for(i=0; i<8; ++i)
+      EXPECT_EQ(1,buf[i]);
+}
+
+
 TEST(SmallPtrSetTest, SwapTest) {
   int buf[10];