Merge pull request #51 from xtonik/MANTISSA

This looks good. Thank you very much for working out this improvement!
wrandelshofer · Oct 25, 2024 · 3ecdbbe · 3ecdbbe
2 parents ec1a73c + ea1c8a9
commit 3ecdbbe
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Showing 2 changed files with 9 additions and 10 deletions.
diff --git a/...ava/ch.randelshofer.fastdoubleparser/ch/randelshofer/fastdoubleparser/FastDoubleMath.java b/...ava/ch.randelshofer.fastdoubleparser/ch/randelshofer/fastdoubleparser/FastDoubleMath.java
@@ -932,14 +932,14 @@ static double tryDecToDoubleWithFastAlgorithm(boolean isNegative, long significa
         mantissa >>>= 1;
 
         // Here we have mantissa < (1<<53), unless there was an overflow
-        if (mantissa >= (1L << DOUBLE_SIGNIFICAND_WIDTH)) {
+        if (mantissa == (1L << DOUBLE_SIGNIFICAND_WIDTH)) {
             // This will happen when parsing values such as 7.2057594037927933e+16
-            mantissa = (1L << (DOUBLE_SIGNIFICAND_WIDTH - 1));
+            mantissa = 0;
             lz--; // undo previous addition
+        } else {
+            mantissa &= ~(1L << (DOUBLE_SIGNIFICAND_WIDTH - 1));
         }
 
-        mantissa &= ~(1L << (DOUBLE_SIGNIFICAND_WIDTH - 1));
-
         long realExponent = exponent - lz;
         // we have to check that realExponent is in range, otherwise we bail out
         if ((realExponent < 1) || (realExponent > DOUBLE_MAX_EXPONENT_POWER_OF_TWO + DOUBLE_EXPONENT_BIAS)) {

diff --git a/...java/ch.randelshofer.fastdoubleparser/ch/randelshofer/fastdoubleparser/FastFloatMath.java b/...java/ch.randelshofer.fastdoubleparser/ch/randelshofer/fastdoubleparser/FastFloatMath.java
@@ -247,15 +247,14 @@ static float tryDecToFloatWithFastAlgorithm(boolean isNegative, long significand
         mantissa >>>= 1;
 
         // Here we have mantissa < (1<<24), unless there was an overflow
-        if (mantissa >= (1L << FLOAT_SIGNIFICAND_WIDTH)) {
-            // This will happen when parsing values such as 7.2057594037927933e+16 ??
-            mantissa = (1L << (FLOAT_SIGNIFICAND_WIDTH - 1));
+        if (mantissa == (1L << FLOAT_SIGNIFICAND_WIDTH)) {
+            // This will happen when parsing values such as 1.4757395E20
+            mantissa = 0;
             lz--; // undo previous addition
+        } else {
+            mantissa &= ~(1L << (FLOAT_SIGNIFICAND_WIDTH - 1));
         }
 
-        mantissa &= ~(1L << (FLOAT_SIGNIFICAND_WIDTH - 1));
-
-
         long real_exponent = exponent - lz;
         // we have to check that real_exponent is in range, otherwise we bail out
         if ((real_exponent < 1) || (real_exponent > FLOAT_MAX_EXPONENT_POWER_OF_TWO + FLOAT_EXPONENT_BIAS)) {