commit 7468b069446f43cc06ae77e71e6f50a9ae3c5fbc
author Chandler Carruth <chandlerc@gmail.com> Fri Oct 10 04:17:04 2014 +0000
committer Chandler Carruth <chandlerc@gmail.com> Fri Oct 10 04:17:04 2014 +0000
tree de7869a59ef2bbeac0d76592efe9736c269bedee
parent 5d1159ebe95b0ac0152a5905369a83b2350e9352

[ADT] Implement the 'logb' functionality for APFloat. This is necessary
to implement complex division in the constant folder of Clang.

llvm-svn: 219471

llvm/unittests/ADT/APFloatTest.cpp

diff --git a/llvm/unittests/ADT/APFloatTest.cpp b/llvm/unittests/ADT/APFloatTest.cpp
index a4816ef..8dd6f9f 100644
--- a/llvm/unittests/ADT/APFloatTest.cpp
+++ b/llvm/unittests/ADT/APFloatTest.cpp
@@ -2691,4 +2691,55 @@
   EXPECT_TRUE(Two.bitwiseIsEqual(One * Two));
   EXPECT_TRUE(One.bitwiseIsEqual(Two / Two));
 }
+
+TEST(APFloatTest, logb) {
+  EXPECT_TRUE(
+      APFloat(APFloat::IEEEsingle, "0x0p+0")
+          .bitwiseIsEqual(logb(APFloat(APFloat::IEEEsingle, "0x1p+0"))));
+  EXPECT_TRUE(
+      APFloat(APFloat::IEEEsingle, "0x0p+0")
+          .bitwiseIsEqual(logb(APFloat(APFloat::IEEEsingle, "-0x1p+0"))));
+  EXPECT_TRUE(
+      APFloat(APFloat::IEEEsingle, "0x2Ap+0")
+          .bitwiseIsEqual(logb(APFloat(APFloat::IEEEsingle, "0x1p+42"))));
+  EXPECT_TRUE(
+      APFloat(APFloat::IEEEsingle, "-0x2Ap+0")
+          .bitwiseIsEqual(logb(APFloat(APFloat::IEEEsingle, "0x1p-42"))));
+
+  APFloat PInf = APFloat::getInf(APFloat::IEEEsingle, false);
+  APFloat MInf = APFloat::getInf(APFloat::IEEEsingle, true);
+  APFloat PZero = APFloat::getZero(APFloat::IEEEsingle, false);
+  APFloat MZero = APFloat::getZero(APFloat::IEEEsingle, true);
+  APFloat QNaN = APFloat::getNaN(APFloat::IEEEsingle, false);
+  APFloat SNaN = APFloat::getSNaN(APFloat::IEEEsingle, false);
+
+  EXPECT_TRUE(PInf.bitwiseIsEqual(logb(PInf)));
+  EXPECT_TRUE(PInf.bitwiseIsEqual(logb(MInf)));
+  EXPECT_TRUE(PZero.bitwiseIsEqual(logb(PZero)));
+  EXPECT_TRUE(MZero.bitwiseIsEqual(logb(MZero)));
+  EXPECT_TRUE(QNaN.bitwiseIsEqual(logb(QNaN)));
+  EXPECT_TRUE(SNaN.bitwiseIsEqual(logb(SNaN)));
+
+  APFloat PLargestValue = APFloat::getLargest(APFloat::IEEEsingle, false);
+  APFloat MLargestValue = APFloat::getLargest(APFloat::IEEEsingle, true);
+  APFloat PSmallestValue = APFloat::getSmallest(APFloat::IEEEsingle, false);
+  APFloat MSmallestValue = APFloat::getSmallest(APFloat::IEEEsingle, true);
+  APFloat PSmallestNormalized =
+      APFloat::getSmallestNormalized(APFloat::IEEEsingle, false);
+  APFloat MSmallestNormalized =
+      APFloat::getSmallestNormalized(APFloat::IEEEsingle, true);
+
+  EXPECT_TRUE(
+      APFloat(APFloat::IEEEsingle, "0x7Fp+0").bitwiseIsEqual(logb(PLargestValue)));
+  EXPECT_TRUE(
+      APFloat(APFloat::IEEEsingle, "0x7Fp+0").bitwiseIsEqual(logb(MLargestValue)));
+  EXPECT_TRUE(
+      APFloat(APFloat::IEEEsingle, "-0x7Ep+0").bitwiseIsEqual(logb(PSmallestValue)));
+  EXPECT_TRUE(
+      APFloat(APFloat::IEEEsingle, "-0x7Ep+0").bitwiseIsEqual(logb(MSmallestValue)));
+  EXPECT_TRUE(APFloat(APFloat::IEEEsingle, "-0x7Ep+0")
+                  .bitwiseIsEqual(logb(PSmallestNormalized)));
+  EXPECT_TRUE(APFloat(APFloat::IEEEsingle, "-0x7Ep+0")
+                  .bitwiseIsEqual(logb(MSmallestNormalized)));
+}
 }