[omg] Make signaling NAN a template for float and double

numworks · Apr 3, 2023 · a7ba636 · a7ba636
1 parent f13e608
commit a7ba636
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Showing 5 changed files with 35 additions and 5 deletions.
diff --git a/apps/shared/continuous_function_cache.cpp b/apps/shared/continuous_function_cache.cpp
@@ -100,7 +100,7 @@ void ContinuousFunctionCache::ComputeNonCartesianSteps(float *tStep,
 // private
 void ContinuousFunctionCache::invalidateBetween(int iInf, int iSup) {
   for (int i = iInf; i < iSup; i++) {
-    m_cache[i] = OMG::SignalingNan();
+    m_cache[i] = OMG::SignalingNan<float>();
   }
 }
 

diff --git a/omg/Makefile b/omg/Makefile
@@ -3,6 +3,7 @@ SFLAGS += -Iomg/include
 omg_src += $(addprefix omg/src/,\
   print.cpp \
   directions.cpp \
+  signaling_nan.cpp\
 )
 
 tests_src += $(addprefix omg/test/,\

diff --git a/omg/include/omg/signaling_nan.h b/omg/include/omg/signaling_nan.h
@@ -15,19 +15,32 @@ union IntFloat {
   float f;
 };
 
+union IntDouble {
+  uint64_t i;
+  double d;
+};
+
 #if __EMSCRIPTEN__
 /* Emscripten cannot represent a NaN literal with custom bit pattern in
  * NaN-canonicalizing JS engines. We use a magic number instead. */
 constexpr static IntFloat k_sNanFloat = IntFloat{.f = -1.7014118346e+38};
+constexpr static IntDouble k_sNanDouble = IntDouble{.d = -1.7014118346e+38};
 #else
-/* 0x7fa00000 corresponds to std::numeric_limits<float>::signaling_NaN() */
+/* 0x7fa00000 corresponds to std::numeric_limits<float>::signaling_NaN()
+ * 0x7ff4000000000000 corresponds to
+ * std::numeric_limits<double>::signaling_NaN() */
 constexpr static IntFloat k_sNanFloat = IntFloat{.i = 0x7fa00000};
+constexpr static IntDouble k_sNanDouble = IntDouble{.i = 0x7ff4000000000000};
 #endif
 
-static bool IsSignalingNan(float f) {
+constexpr static bool IsSignalingNan(float f) {
   return IntFloat{.f = f}.i == k_sNanFloat.i;
 }
-static float SignalingNan() { return k_sNanFloat.f; }
+constexpr static bool IsSignalingNan(double d) {
+  return IntDouble{.d = d}.i == k_sNanDouble.i;
+}
+template <typename T>
+T SignalingNan();
 
 }  // namespace OMG
 

diff --git a/omg/src/signaling_nan.cpp b/omg/src/signaling_nan.cpp
@@ -0,0 +1,14 @@
+#include <omg/signaling_nan.h>
+
+namespace OMG {
+
+template <typename T>
+T SignalingNan() {
+  return sizeof(T) == sizeof(float) ? static_cast<T>(k_sNanFloat.f)
+                                    : static_cast<T>(k_sNanDouble.d);
+}
+
+template float SignalingNan<float>();
+template double SignalingNan<double>();
+
+}  // namespace OMG
diff --git a/omg/test/signaling_nan.cpp b/omg/test/signaling_nan.cpp
@@ -5,6 +5,8 @@
 using namespace OMG;
 
 QUIZ_CASE(omg_signaling_nan) {
-  quiz_assert(OMG::IsSignalingNan(OMG::SignalingNan()));
+  quiz_assert(OMG::IsSignalingNan(OMG::SignalingNan<float>()));
+  quiz_assert(OMG::IsSignalingNan(OMG::SignalingNan<double>()));
   quiz_assert(!OMG::IsSignalingNan(static_cast<float>(NAN)));
+  quiz_assert(!OMG::IsSignalingNan(static_cast<double>(NAN)));
 }