[llvm] r298867 - [APInt] Use memset in setAllBits.

[Craig Topper via llvm-commits]

Author: ctopper
Date: Mon Mar 27 12:50:54 2017
New Revision: 298867

URL: http://llvm.org/viewvc/llvm-project?rev=298867&view=rev
Log:
[APInt] Use memset in setAllBits.

Modified:
    llvm/trunk/include/llvm/ADT/APInt.h
    llvm/trunk/unittests/ADT/APIntTest.cpp

Modified: llvm/trunk/include/llvm/ADT/APInt.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/APInt.h?rev=298867&r1=298866&r2=298867&view=diff
==============================================================================
--- llvm/trunk/include/llvm/ADT/APInt.h (original)
+++ llvm/trunk/include/llvm/ADT/APInt.h Mon Mar 27 12:50:54 2017
@@ -1164,11 +1164,9 @@ public:
   void setAllBits() {
     if (isSingleWord())
       VAL = UINT64_MAX;
-    else {
+    else
       // Set all the bits in all the words.
-      for (unsigned i = 0; i < getNumWords(); ++i)
-        pVal[i] = UINT64_MAX;
-    }
+      memset(pVal, -1, getNumWords() * APINT_WORD_SIZE);
     // Clear the unused ones
     clearUnusedBits();
   }

Modified: llvm/trunk/unittests/ADT/APIntTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/ADT/APIntTest.cpp?rev=298867&r1=298866&r2=298867&view=diff
==============================================================================
--- llvm/trunk/unittests/ADT/APIntTest.cpp (original)
+++ llvm/trunk/unittests/ADT/APIntTest.cpp Mon Mar 27 12:50:54 2017
@@ -1895,3 +1895,41 @@ TEST(APIntTest, setBitsFrom) {
   EXPECT_EQ(0u, i64from63.countTrailingOnes());
   EXPECT_EQ(1u, i64from63.countPopulation());
 }
+
+TEST(APIntTest, setAllBits) {
+  APInt i32(32, 0);
+  i32.setAllBits();
+  EXPECT_EQ(32u, i32.countLeadingOnes());
+  EXPECT_EQ(0u, i32.countLeadingZeros());
+  EXPECT_EQ(32u, i32.getActiveBits());
+  EXPECT_EQ(0u, i32.countTrailingZeros());
+  EXPECT_EQ(32u, i32.countTrailingOnes());
+  EXPECT_EQ(32u, i32.countPopulation());
+
+  APInt i64(64, 0);
+  i64.setAllBits();
+  EXPECT_EQ(64u, i64.countLeadingOnes());
+  EXPECT_EQ(0u, i64.countLeadingZeros());
+  EXPECT_EQ(64u, i64.getActiveBits());
+  EXPECT_EQ(0u, i64.countTrailingZeros());
+  EXPECT_EQ(64u, i64.countTrailingOnes());
+  EXPECT_EQ(64u, i64.countPopulation());
+
+  APInt i96(96, 0);
+  i96.setAllBits();
+  EXPECT_EQ(96u, i96.countLeadingOnes());
+  EXPECT_EQ(0u, i96.countLeadingZeros());
+  EXPECT_EQ(96u, i96.getActiveBits());
+  EXPECT_EQ(0u, i96.countTrailingZeros());
+  EXPECT_EQ(96u, i96.countTrailingOnes());
+  EXPECT_EQ(96u, i96.countPopulation());
+
+  APInt i128(128, 0);
+  i128.setAllBits();
+  EXPECT_EQ(128u, i128.countLeadingOnes());
+  EXPECT_EQ(0u, i128.countLeadingZeros());
+  EXPECT_EQ(128u, i128.getActiveBits());
+  EXPECT_EQ(0u, i128.countTrailingZeros());
+  EXPECT_EQ(128u, i128.countTrailingOnes());
+  EXPECT_EQ(128u, i128.countPopulation());
+}