Push version 2.5.6 to trunk.
Added support for VFP rounding modes to the ARM simulator.
Fixed multiplication overflow bug (issue 927).
Added a limit for the amount of executable memory (issue 925).
git-svn-id: http://v8.googlecode.com/svn/trunk@5804 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
diff --git a/src/double.h b/src/double.h
index e805173..65eded9 100644
--- a/src/double.h
+++ b/src/double.h
@@ -54,18 +54,20 @@
explicit Double(DiyFp diy_fp)
: d64_(DiyFpToUint64(diy_fp)) {}
+ // The value encoded by this Double must be greater or equal to +0.0.
+ // It must not be special (infinity, or NaN).
DiyFp AsDiyFp() const {
+ ASSERT(Sign() > 0);
ASSERT(!IsSpecial());
return DiyFp(Significand(), Exponent());
}
- // this->Significand() must not be 0.
+ // The value encoded by this Double must be strictly greater than 0.
DiyFp AsNormalizedDiyFp() const {
+ ASSERT(value() > 0.0);
uint64_t f = Significand();
int e = Exponent();
- ASSERT(f != 0);
-
// The current double could be a denormal.
while ((f & kHiddenBit) == 0) {
f <<= 1;
@@ -82,6 +84,20 @@
return d64_;
}
+ // Returns the next greater double. Returns +infinity on input +infinity.
+ double NextDouble() const {
+ if (d64_ == kInfinity) return Double(kInfinity).value();
+ if (Sign() < 0 && Significand() == 0) {
+ // -0.0
+ return 0.0;
+ }
+ if (Sign() < 0) {
+ return Double(d64_ - 1).value();
+ } else {
+ return Double(d64_ + 1).value();
+ }
+ }
+
int Exponent() const {
if (IsDenormal()) return kDenormalExponent;
@@ -120,24 +136,30 @@
((d64 & kSignificandMask) != 0);
}
-
bool IsInfinite() const {
uint64_t d64 = AsUint64();
return ((d64 & kExponentMask) == kExponentMask) &&
((d64 & kSignificandMask) == 0);
}
-
int Sign() const {
uint64_t d64 = AsUint64();
return (d64 & kSignMask) == 0? 1: -1;
}
+ // Precondition: the value encoded by this Double must be greater or equal
+ // than +0.0.
+ DiyFp UpperBoundary() const {
+ ASSERT(Sign() > 0);
+ return DiyFp(Significand() * 2 + 1, Exponent() - 1);
+ }
// Returns the two boundaries of this.
// The bigger boundary (m_plus) is normalized. The lower boundary has the same
// exponent as m_plus.
+ // Precondition: the value encoded by this Double must be greater than 0.
void NormalizedBoundaries(DiyFp* out_m_minus, DiyFp* out_m_plus) const {
+ ASSERT(value() > 0.0);
DiyFp v = this->AsDiyFp();
bool significand_is_zero = (v.f() == kHiddenBit);
DiyFp m_plus = DiyFp::Normalize(DiyFp((v.f() << 1) + 1, v.e() - 1));