commit ea00b499c703bbdbf4c87573cf2fe5b46a0bf1c2
author Matt Arsenault <Matthew.Arsenault@amd.com> Wed Mar 23 23:51:45 2016 +0000
committer Matt Arsenault <Matthew.Arsenault@amd.com> Wed Mar 23 23:51:45 2016 +0000
tree 662608e8cdefe69d39b0620f5c3690add0796c0b
parent cbfe7bb72e6de9db72bbcbe8c697bf3b7627e18d

APFloat: Fix signalling nans for scalbn

llvm-svn: 264219

llvm/unittests/ADT/APFloatTest.cpp

diff --git a/llvm/unittests/ADT/APFloatTest.cpp b/llvm/unittests/ADT/APFloatTest.cpp
index 01dcffa..d884c8a 100644
--- a/llvm/unittests/ADT/APFloatTest.cpp
+++ b/llvm/unittests/ADT/APFloatTest.cpp
@@ -2890,7 +2890,22 @@
   EXPECT_TRUE(MZero.bitwiseIsEqual(scalbn(MZero, 0, RM)));
   EXPECT_TRUE(QPNaN.bitwiseIsEqual(scalbn(QPNaN, 0, RM)));
   EXPECT_TRUE(QMNaN.bitwiseIsEqual(scalbn(QMNaN, 0, RM)));
-  EXPECT_TRUE(SNaN.bitwiseIsEqual(scalbn(SNaN, 0, RM)));
+  EXPECT_FALSE(scalbn(SNaN, 0, RM).isSignaling());
+
+  APFloat ScalbnSNaN = scalbn(SNaN, 1, RM);
+  EXPECT_TRUE(ScalbnSNaN.isNaN() && !ScalbnSNaN.isSignaling());
+
+  // Make sure highest bit of payload is preserved.
+  const APInt Payload(64, (UINT64_C(1) << 50) |
+                      (UINT64_C(1) << 49) |
+                      (UINT64_C(1234) << 32) |
+                      1);
+
+  APFloat SNaNWithPayload = APFloat::getSNaN(APFloat::IEEEdouble, false,
+                                             &Payload);
+  APFloat QuietPayload = scalbn(SNaNWithPayload, 1, RM);
+  EXPECT_TRUE(QuietPayload.isNaN() && !QuietPayload.isSignaling());
+  EXPECT_EQ(Payload, QuietPayload.bitcastToAPInt().getLoBits(51));
 
   EXPECT_TRUE(PInf.bitwiseIsEqual(
                 scalbn(APFloat(APFloat::IEEEsingle, "0x1p+0"), 128, RM)));