using namespace llvm;
+const uint32_t BranchProbability::D;
+
raw_ostream &BranchProbability::print(raw_ostream &OS) const {
- auto GetHexDigit = [](int Val) -> char {
- assert(Val < 16);
- if (Val < 10)
- return '0' + Val;
- return 'a' + Val - 10;
- };
- OS << "0x";
- for (int Digits = 0; Digits < 8; ++Digits)
- OS << GetHexDigit(N >> (28 - Digits * 4) & 0xf);
- OS << " / 0x";
- for (int Digits = 0; Digits < 8; ++Digits)
- OS << GetHexDigit(D >> (28 - Digits * 4) & 0xf);
- OS << " = " << format("%.2f%%", ((double)N / D) * 100.0);
- return OS;
+ if (isUnknown())
+ return OS << "?%";
+
+ // Get a percentage rounded to two decimal digits. This avoids
+ // implementation-defined rounding inside printf.
+ double Percent = rint(((double)N / D) * 100.0 * 100.0) / 100.0;
+ return OS << format("0x%08" PRIx32 " / 0x%08" PRIx32 " = %.2f%%", N, D,
+ Percent);
}
void BranchProbability::dump() const { print(dbgs()) << '\n'; }
}
}
-BranchProbability &BranchProbability::operator+=(BranchProbability RHS) {
- assert(N <= D - RHS.N &&
- "The sum of branch probabilities should not exceed one!");
- N += RHS.N;
- return *this;
-}
-
-BranchProbability &BranchProbability::operator-=(BranchProbability RHS) {
- assert(N >= RHS.N &&
- "Can only subtract a smaller probability from a larger one!");
- N -= RHS.N;
- return *this;
+BranchProbability
+BranchProbability::getBranchProbability(uint64_t Numerator,
+ uint64_t Denominator) {
+ assert(Numerator <= Denominator && "Probability cannot be bigger than 1!");
+ // Scale down Denominator to fit in a 32-bit integer.
+ int Scale = 0;
+ while (Denominator > UINT32_MAX) {
+ Denominator >>= 1;
+ Scale++;
+ }
+ return BranchProbability(Numerator >> Scale, Denominator);
}
// If ConstD is not zero, then replace D by ConstD so that division and modulo
// operations by D can be optimized, in case this function is not inlined by the
// compiler.
template <uint32_t ConstD>
-inline uint64_t scale(uint64_t Num, uint32_t N, uint32_t D) {
+static uint64_t scale(uint64_t Num, uint32_t N, uint32_t D) {
if (ConstD > 0)
D = ConstD;