Compute error statistics of normal precision

1 files changed, 45 insertions, 0 deletions

diff --git a/test/unittest/readertest.cpp b/test/unittest/readertest.cpp
index 7d45755c..be987abb 100644
--- a/test/unittest/readertest.cpp
+++ b/test/unittest/readertest.cpp
@@ -266,6 +266,51 @@ TEST(Reader, ParseNumber_FullPrecisionDouble) {
     TestParseDouble<true>();

 }

 

+TEST(Reader, ParseNumber_NormalPrecisionError) {

+    static unsigned count = 1000000;

+    static const uint64_t kSignMask = RAPIDJSON_UINT64_C2(0x80000000, 0);

+

+    union {

+        double d;

+        uint64_t u;

+

+        uint64_t ToBias() const {

+            if (u & kSignMask)

+                return ~u + 1;

+            else

+                return u | kSignMask;

+        }

+    }u, a;

+    Random r;

+

+    double ulpSum = 0.0;

+    double ulpMax = 0.0;

+    for (unsigned i = 0; i < count; i++) {

+        do {

+            // Need to call r() in two statements for cross-platform coherent sequence.

+            u.u = uint64_t(r()) << 32;

+            u.u |= uint64_t(r());

+        } while (std::isnan(u.d) || std::isinf(u.d) || !std::isnormal(u.d));

+

+        char buffer[32];

+        *internal::dtoa(u.d, buffer) = '\0';

+

+        StringStream s(buffer);

+        ParseDoubleHandler h;

+        Reader reader;

+        ASSERT_EQ(kParseErrorNone, reader.Parse(s, h).Code());

+        EXPECT_EQ(1u, h.step_);

+

+        a.d = h.actual_;

+        uint64_t bias1 = u.ToBias();

+        uint64_t bias2 = a.ToBias();

+        double ulp = bias1 >= bias2 ? bias1 - bias2 : bias2 - bias1;

+        ulpMax = std::max(ulpMax, ulp);

+        ulpSum += ulp;

+    }

+    printf("ULP Average = %g, Max = %g \n", ulpSum / count, ulpMax);

+}

+

 TEST(Reader, ParseNumber_Error) {

 #define TEST_NUMBER_ERROR(errorCode, str) \

     { \