commit 1ff74b0d2d4ea976a0191f391e506cd1f8fd338b
author Owen Anderson <resistor@mac.com> Wed Aug 15 05:39:46 2012 +0000
committer Owen Anderson <resistor@mac.com> Wed Aug 15 05:39:46 2012 +0000
tree 9fa1171172e27381f469ae952c03104773eab309
parent 1049611070b64538c3c3dd771a24b95944c64d8c

Fix a problem with APFloat::roundToIntegral where it would return incorrect results for negative inputs to trunc.  Add unit tests to verify this behavior.

llvm-svn: 161929

llvm/unittests/ADT/APFloatTest.cpp

diff --git a/llvm/unittests/ADT/APFloatTest.cpp b/llvm/unittests/ADT/APFloatTest.cpp
index cc207f7..caa288a 100644
--- a/llvm/unittests/ADT/APFloatTest.cpp
+++ b/llvm/unittests/ADT/APFloatTest.cpp
@@ -648,6 +648,36 @@
   EXPECT_FALSE(APFloat(1.40129846e-45f).getExactInverse(0));
 }
 
+TEST(APFloatTest, roundToIntegral) {
+  APFloat T(-0.5), S(3.14), P(0.0);
+
+  P = T;
+  P.roundToIntegral(APFloat::rmTowardZero);
+  EXPECT_EQ(-0.0, P.convertToDouble());
+  P = T;
+  P.roundToIntegral(APFloat::rmTowardNegative);
+  EXPECT_EQ(-1.0, P.convertToDouble());
+  P = T;
+  P.roundToIntegral(APFloat::rmTowardPositive);
+  EXPECT_EQ(-0.0, P.convertToDouble());
+  P = T;
+  P.roundToIntegral(APFloat::rmNearestTiesToEven);
+  EXPECT_EQ(-0.0, P.convertToDouble());
+
+  P = S;
+  P.roundToIntegral(APFloat::rmTowardZero);
+  EXPECT_EQ(3.0, P.convertToDouble());
+  P = S;
+  P.roundToIntegral(APFloat::rmTowardNegative);
+  EXPECT_EQ(3.0, P.convertToDouble());
+  P = S;
+  P.roundToIntegral(APFloat::rmTowardPositive);
+  EXPECT_EQ(4.0, P.convertToDouble());
+  P = S;
+  P.roundToIntegral(APFloat::rmNearestTiesToEven);
+  EXPECT_EQ(3.0, P.convertToDouble());
+}
+
 TEST(APFloatTest, getLargest) {
   EXPECT_EQ(3.402823466e+38f, APFloat::getLargest(APFloat::IEEEsingle).convertToFloat());
   EXPECT_EQ(1.7976931348623158e+308, APFloat::getLargest(APFloat::IEEEdouble).convertToDouble());