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| author | dim <dim@FreeBSD.org> | 2011-05-02 19:34:44 +0000 |
|---|---|---|
| committer | dim <dim@FreeBSD.org> | 2011-05-02 19:34:44 +0000 |
| commit | 2b066988909948dc3d53d01760bc2d71d32f3feb (patch) | |
| tree | fc5f365fb9035b2d0c622bbf06c9bbe8627d7279 /lib/Support/APInt.cpp | |
| parent | c80ac9d286b8fcc6d1ee5d76048134cf80aa9edc (diff) | |
| download | FreeBSD-src-2b066988909948dc3d53d01760bc2d71d32f3feb.zip FreeBSD-src-2b066988909948dc3d53d01760bc2d71d32f3feb.tar.gz | |
Vendor import of llvm trunk r130700:
http://llvm.org/svn/llvm-project/llvm/trunk@130700
Diffstat (limited to 'lib/Support/APInt.cpp')
| -rw-r--r-- | lib/Support/APInt.cpp | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/lib/Support/APInt.cpp b/lib/Support/APInt.cpp index 08f36d2..23a22ac 100644 --- a/lib/Support/APInt.cpp +++ b/lib/Support/APInt.cpp @@ -1517,13 +1517,15 @@ APInt::ms APInt::magic() const { /// division by a constant as a sequence of multiplies, adds and shifts. /// Requires that the divisor not be 0. Taken from "Hacker's Delight", Henry /// S. Warren, Jr., chapter 10. -APInt::mu APInt::magicu() const { +/// LeadingZeros can be used to simplify the calculation if the upper bits +/// of the divided value are known zero. +APInt::mu APInt::magicu(unsigned LeadingZeros) const { const APInt& d = *this; unsigned p; APInt nc, delta, q1, r1, q2, r2; struct mu magu; magu.a = 0; // initialize "add" indicator - APInt allOnes = APInt::getAllOnesValue(d.getBitWidth()); + APInt allOnes = APInt::getAllOnesValue(d.getBitWidth()).lshr(LeadingZeros); APInt signedMin = APInt::getSignedMinValue(d.getBitWidth()); APInt signedMax = APInt::getSignedMaxValue(d.getBitWidth()); @@ -2076,6 +2078,16 @@ APInt APInt::smul_ov(const APInt &RHS, bool &Overflow) const { return Res; } +APInt APInt::umul_ov(const APInt &RHS, bool &Overflow) const { + APInt Res = *this * RHS; + + if (*this != 0 && RHS != 0) + Overflow = Res.udiv(RHS) != *this || Res.udiv(*this) != RHS; + else + Overflow = false; + return Res; +} + APInt APInt::sshl_ov(unsigned ShAmt, bool &Overflow) const { Overflow = ShAmt >= getBitWidth(); if (Overflow) |
