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-rw-r--r--lib/Support/APFloat.cpp38
1 files changed, 28 insertions, 10 deletions
diff --git a/lib/Support/APFloat.cpp b/lib/Support/APFloat.cpp
index 409d4fb..2139df5 100644
--- a/lib/Support/APFloat.cpp
+++ b/lib/Support/APFloat.cpp
@@ -1765,6 +1765,32 @@ APFloat::fusedMultiplyAdd(const APFloat &multiplicand,
return fs;
}
+/* Rounding-mode corrrect round to integral value. */
+APFloat::opStatus APFloat::roundToIntegral(roundingMode rounding_mode) {
+ opStatus fs;
+ assertArithmeticOK(*semantics);
+
+ // The algorithm here is quite simple: we add 2^(p-1), where p is the
+ // precision of our format, and then subtract it back off again. The choice
+ // of rounding modes for the addition/subtraction determines the rounding mode
+ // for our integral rounding as well.
+ APInt IntegerConstant(NextPowerOf2(semanticsPrecision(*semantics)),
+ 1 << (semanticsPrecision(*semantics)-1));
+ APFloat MagicConstant(*semantics);
+ fs = MagicConstant.convertFromAPInt(IntegerConstant, false,
+ rmNearestTiesToEven);
+ if (fs != opOK)
+ return fs;
+
+ fs = add(MagicConstant, rounding_mode);
+ if (fs != opOK && fs != opInexact)
+ return fs;
+
+ fs = subtract(MagicConstant, rounding_mode);
+ return fs;
+}
+
+
/* Comparison requires normalized numbers. */
APFloat::cmpResult
APFloat::compare(const APFloat &rhs) const
@@ -3278,16 +3304,8 @@ APFloat::APFloat(double d) : exponent2(0), sign2(0) {
}
namespace {
- static void append(SmallVectorImpl<char> &Buffer,
- unsigned N, const char *Str) {
- unsigned Start = Buffer.size();
- Buffer.set_size(Start + N);
- memcpy(&Buffer[Start], Str, N);
- }
-
- template <unsigned N>
- void append(SmallVectorImpl<char> &Buffer, const char (&Str)[N]) {
- append(Buffer, N, Str);
+ void append(SmallVectorImpl<char> &Buffer, StringRef Str) {
+ Buffer.append(Str.begin(), Str.end());
}
/// Removes data from the given significand until it is no more
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