From: Mon P Wang <wangmp@apple.com>
Date: Thu, 29 Apr 2010 05:53:29 +0000 (+0000)
Subject: A not equal for an unordered relation should return true as specified in IEEE-754... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=fc39dc4c7886723310419b1869cf651ca55b7af4;p=clang

A not equal for an unordered relation should return true as specified in IEEE-754, e.g.,
NAN != NAN ? 1 : 0 should return 1.  Also fix the case for complex.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@102598 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp
index 1c2b76eede..c1a42d88ff 100644
--- a/lib/AST/ExprConstant.cpp
+++ b/lib/AST/ExprConstant.cpp
@@ -1119,9 +1119,11 @@ bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
         assert(E->getOpcode() == BinaryOperator::NE &&
                "Invalid complex comparison.");
         return Success(((CR_r == APFloat::cmpGreaterThan ||
-                         CR_r == APFloat::cmpLessThan) &&
+                         CR_r == APFloat::cmpLessThan ||
+                         CR_r == APFloat::cmpUnordered) ||
                         (CR_i == APFloat::cmpGreaterThan ||
-                         CR_i == APFloat::cmpLessThan)), E);
+                         CR_i == APFloat::cmpLessThan ||
+                         CR_i == APFloat::cmpUnordered)), E);
       }
     } else {
       if (E->getOpcode() == BinaryOperator::EQ)
@@ -1164,7 +1166,8 @@ bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
       return Success(CR == APFloat::cmpEqual, E);
     case BinaryOperator::NE:
       return Success(CR == APFloat::cmpGreaterThan
-                     || CR == APFloat::cmpLessThan, E);
+                     || CR == APFloat::cmpLessThan
+                     || CR == APFloat::cmpUnordered, E);
     }
   }
 
diff --git a/test/CodeGen/const-unordered-compare.c b/test/CodeGen/const-unordered-compare.c
new file mode 100644
index 0000000000..ac7d35bcd5
--- /dev/null
+++ b/test/CodeGen/const-unordered-compare.c
@@ -0,0 +1,7 @@
+// RUN: %clang_cc1 -emit-llvm -o - %s | FileCheck %s
+
+// Checks folding of an unordered comparison
+int nan_ne_check() {
+  // CHECK: store i32 1
+  return (__builtin_nanf("") != __builtin_nanf("")) ? 1 : 0;
+}