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Reapply "blockfreq: Rewrite BlockFrequencyInfoImpl"
This reverts commit r206707, reapplying r206704. The preceding commit to CalcSpillWeights should have sorted out the failing buildbots. <rdar://problem/14292693> git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206766 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Duncan P. N. Exon Smith
File diff suppressed because it is too large
Load Diff
@@ -11,6 +11,7 @@
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//
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//===----------------------------------------------------------------------===//
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#define DEBUG_TYPE "block-freq"
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#include "llvm/Analysis/BlockFrequencyInfo.h"
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#include "llvm/Analysis/BlockFrequencyInfoImpl.h"
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#include "llvm/Analysis/BranchProbabilityInfo.h"
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@@ -106,6 +107,7 @@ struct DOTGraphTraits<BlockFrequencyInfo*> : public DefaultDOTGraphTraits {
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INITIALIZE_PASS_BEGIN(BlockFrequencyInfo, "block-freq",
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"Block Frequency Analysis", true, true)
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INITIALIZE_PASS_DEPENDENCY(BranchProbabilityInfo)
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INITIALIZE_PASS_DEPENDENCY(LoopInfo)
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INITIALIZE_PASS_END(BlockFrequencyInfo, "block-freq",
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"Block Frequency Analysis", true, true)
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@@ -120,14 +122,16 @@ BlockFrequencyInfo::~BlockFrequencyInfo() {}
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void BlockFrequencyInfo::getAnalysisUsage(AnalysisUsage &AU) const {
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AU.addRequired<BranchProbabilityInfo>();
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AU.addRequired<LoopInfo>();
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AU.setPreservesAll();
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}
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bool BlockFrequencyInfo::runOnFunction(Function &F) {
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BranchProbabilityInfo &BPI = getAnalysis<BranchProbabilityInfo>();
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LoopInfo &LI = getAnalysis<LoopInfo>();
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if (!BFI)
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BFI.reset(new ImplType);
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BFI->doFunction(&F, &BPI);
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BFI->doFunction(&F, &BPI, &LI);
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#ifndef NDEBUG
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if (ViewBlockFreqPropagationDAG != GVDT_None)
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view();
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@@ -158,7 +162,7 @@ void BlockFrequencyInfo::view() const {
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}
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const Function *BlockFrequencyInfo::getFunction() const {
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return BFI ? BFI->Fn : nullptr;
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return BFI ? BFI->getFunction() : nullptr;
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}
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raw_ostream &BlockFrequencyInfo::
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932
lib/Analysis/BlockFrequencyInfoImpl.cpp
Normal file
932
lib/Analysis/BlockFrequencyInfoImpl.cpp
Normal file
@@ -0,0 +1,932 @@
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//===- BlockFrequencyImplInfo.cpp - Block Frequency Info Implementation ---===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// Loops should be simplified before this analysis.
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//
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//===----------------------------------------------------------------------===//
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#define DEBUG_TYPE "block-freq"
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#include "llvm/Analysis/BlockFrequencyInfoImpl.h"
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#include "llvm/ADT/APFloat.h"
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#include "llvm/Support/raw_ostream.h"
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#include <deque>
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using namespace llvm;
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//===----------------------------------------------------------------------===//
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//
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// PositiveFloat implementation.
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//
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//===----------------------------------------------------------------------===//
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#ifndef _MSC_VER
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const int32_t PositiveFloatBase::MaxExponent;
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const int32_t PositiveFloatBase::MinExponent;
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#endif
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static void appendDigit(std::string &Str, unsigned D) {
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assert(D < 10);
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Str += '0' + D % 10;
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}
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static void appendNumber(std::string &Str, uint64_t N) {
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while (N) {
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appendDigit(Str, N % 10);
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N /= 10;
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}
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}
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static bool doesRoundUp(char Digit) {
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switch (Digit) {
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case '5':
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case '6':
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case '7':
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case '8':
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case '9':
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return true;
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default:
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return false;
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}
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}
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static std::string toStringAPFloat(uint64_t D, int E, unsigned Precision) {
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assert(E >= PositiveFloatBase::MinExponent);
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assert(E <= PositiveFloatBase::MaxExponent);
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// Find a new E, but don't let it increase past MaxExponent.
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int LeadingZeros = PositiveFloatBase::countLeadingZeros64(D);
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int NewE = std::min(PositiveFloatBase::MaxExponent, E + 63 - LeadingZeros);
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int Shift = 63 - (NewE - E);
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assert(Shift <= LeadingZeros);
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assert(Shift == LeadingZeros || NewE == PositiveFloatBase::MaxExponent);
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D <<= Shift;
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E = NewE;
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// Check for a denormal.
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unsigned AdjustedE = E + 16383;
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if (!(D >> 63)) {
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assert(E == PositiveFloatBase::MaxExponent);
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AdjustedE = 0;
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}
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// Build the float and print it.
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uint64_t RawBits[2] = {D, AdjustedE};
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APFloat Float(APFloat::x87DoubleExtended, APInt(80, RawBits));
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SmallVector<char, 24> Chars;
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Float.toString(Chars, Precision, 0);
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return std::string(Chars.begin(), Chars.end());
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}
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static std::string stripTrailingZeros(const std::string &Float) {
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size_t NonZero = Float.find_last_not_of('0');
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assert(NonZero != std::string::npos && "no . in floating point string");
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if (Float[NonZero] == '.')
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++NonZero;
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return Float.substr(0, NonZero + 1);
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}
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std::string PositiveFloatBase::toString(uint64_t D, int16_t E, int Width,
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unsigned Precision) {
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if (!D)
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return "0.0";
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// Canonicalize exponent and digits.
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uint64_t Above0 = 0;
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uint64_t Below0 = 0;
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uint64_t Extra = 0;
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int ExtraShift = 0;
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if (E == 0) {
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Above0 = D;
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} else if (E > 0) {
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if (int Shift = std::min(int16_t(countLeadingZeros64(D)), E)) {
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D <<= Shift;
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E -= Shift;
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if (!E)
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Above0 = D;
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}
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} else if (E > -64) {
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Above0 = D >> -E;
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Below0 = D << (64 + E);
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} else if (E > -120) {
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Below0 = D >> (-E - 64);
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Extra = D << (128 + E);
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ExtraShift = -64 - E;
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}
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// Fall back on APFloat for very small and very large numbers.
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if (!Above0 && !Below0)
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return toStringAPFloat(D, E, Precision);
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// Append the digits before the decimal.
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std::string Str;
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size_t DigitsOut = 0;
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if (Above0) {
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appendNumber(Str, Above0);
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DigitsOut = Str.size();
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} else
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appendDigit(Str, 0);
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std::reverse(Str.begin(), Str.end());
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// Return early if there's nothing after the decimal.
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if (!Below0)
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return Str + ".0";
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// Append the decimal and beyond.
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Str += '.';
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uint64_t Error = UINT64_C(1) << (64 - Width);
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// We need to shift Below0 to the right to make space for calculating
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// digits. Save the precision we're losing in Extra.
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Extra = (Below0 & 0xf) << 56 | (Extra >> 8);
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Below0 >>= 4;
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size_t SinceDot = 0;
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size_t AfterDot = Str.size();
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do {
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if (ExtraShift) {
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--ExtraShift;
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Error *= 5;
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} else
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Error *= 10;
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Below0 *= 10;
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Extra *= 10;
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Below0 += (Extra >> 60);
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Extra = Extra & (UINT64_MAX >> 4);
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appendDigit(Str, Below0 >> 60);
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Below0 = Below0 & (UINT64_MAX >> 4);
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if (DigitsOut || Str.back() != '0')
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++DigitsOut;
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++SinceDot;
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} while (Error && (Below0 << 4 | Extra >> 60) >= Error / 2 &&
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(!Precision || DigitsOut <= Precision || SinceDot < 2));
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// Return early for maximum precision.
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if (!Precision || DigitsOut <= Precision)
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return stripTrailingZeros(Str);
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// Find where to truncate.
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size_t Truncate =
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std::max(Str.size() - (DigitsOut - Precision), AfterDot + 1);
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// Check if there's anything to truncate.
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if (Truncate >= Str.size())
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return stripTrailingZeros(Str);
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bool Carry = doesRoundUp(Str[Truncate]);
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if (!Carry)
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return stripTrailingZeros(Str.substr(0, Truncate));
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// Round with the first truncated digit.
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for (std::string::reverse_iterator I(Str.begin() + Truncate), E = Str.rend();
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I != E; ++I) {
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if (*I == '.')
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continue;
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if (*I == '9') {
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*I = '0';
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continue;
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}
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++*I;
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Carry = false;
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break;
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}
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// Add "1" in front if we still need to carry.
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return stripTrailingZeros(std::string(Carry, '1') + Str.substr(0, Truncate));
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}
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raw_ostream &PositiveFloatBase::print(raw_ostream &OS, uint64_t D, int16_t E,
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int Width, unsigned Precision) {
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return OS << toString(D, E, Width, Precision);
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}
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void PositiveFloatBase::dump(uint64_t D, int16_t E, int Width) {
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print(dbgs(), D, E, Width, 0) << "[" << Width << ":" << D << "*2^" << E
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<< "]";
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}
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static std::pair<uint64_t, int16_t>
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getRoundedFloat(uint64_t N, bool ShouldRound, int64_t Shift) {
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if (ShouldRound)
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if (!++N)
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// Rounding caused an overflow.
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return std::make_pair(UINT64_C(1), Shift + 64);
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return std::make_pair(N, Shift);
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}
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std::pair<uint64_t, int16_t> PositiveFloatBase::divide64(uint64_t Dividend,
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uint64_t Divisor) {
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// Input should be sanitized.
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assert(Divisor);
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assert(Dividend);
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// Minimize size of divisor.
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int16_t Shift = 0;
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if (int Zeros = countTrailingZeros(Divisor)) {
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Shift -= Zeros;
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Divisor >>= Zeros;
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}
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// Check for powers of two.
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if (Divisor == 1)
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return std::make_pair(Dividend, Shift);
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// Maximize size of dividend.
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if (int Zeros = countLeadingZeros64(Dividend)) {
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Shift -= Zeros;
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Dividend <<= Zeros;
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}
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// Start with the result of a divide.
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uint64_t Quotient = Dividend / Divisor;
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Dividend %= Divisor;
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// Continue building the quotient with long division.
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//
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// TODO: continue with largers digits.
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while (!(Quotient >> 63) && Dividend) {
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// Shift Dividend, and check for overflow.
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bool IsOverflow = Dividend >> 63;
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Dividend <<= 1;
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--Shift;
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// Divide.
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bool DoesDivide = IsOverflow || Divisor <= Dividend;
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Quotient = (Quotient << 1) | uint64_t(DoesDivide);
|
||||
Dividend -= DoesDivide ? Divisor : 0;
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}
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// Round.
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if (Dividend >= getHalf(Divisor))
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if (!++Quotient)
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// Rounding caused an overflow in Quotient.
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return std::make_pair(UINT64_C(1), Shift + 64);
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return getRoundedFloat(Quotient, Dividend >= getHalf(Divisor), Shift);
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}
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std::pair<uint64_t, int16_t> PositiveFloatBase::multiply64(uint64_t L,
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uint64_t R) {
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// Separate into two 32-bit digits (U.L).
|
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uint64_t UL = L >> 32, LL = L & UINT32_MAX, UR = R >> 32, LR = R & UINT32_MAX;
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// Compute cross products.
|
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uint64_t P1 = UL * UR, P2 = UL * LR, P3 = LL * UR, P4 = LL * LR;
|
||||
|
||||
// Sum into two 64-bit digits.
|
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uint64_t Upper = P1, Lower = P4;
|
||||
auto addWithCarry = [&](uint64_t N) {
|
||||
uint64_t NewLower = Lower + (N << 32);
|
||||
Upper += (N >> 32) + (NewLower < Lower);
|
||||
Lower = NewLower;
|
||||
};
|
||||
addWithCarry(P2);
|
||||
addWithCarry(P3);
|
||||
|
||||
// Check whether the upper digit is empty.
|
||||
if (!Upper)
|
||||
return std::make_pair(Lower, 0);
|
||||
|
||||
// Shift as little as possible to maximize precision.
|
||||
unsigned LeadingZeros = countLeadingZeros64(Upper);
|
||||
int16_t Shift = 64 - LeadingZeros;
|
||||
if (LeadingZeros)
|
||||
Upper = Upper << LeadingZeros | Lower >> Shift;
|
||||
bool ShouldRound = Shift && (Lower & UINT64_C(1) << (Shift - 1));
|
||||
return getRoundedFloat(Upper, ShouldRound, Shift);
|
||||
}
|
||||
|
||||
//===----------------------------------------------------------------------===//
|
||||
//
|
||||
// BlockMass implementation.
|
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//
|
||||
//===----------------------------------------------------------------------===//
|
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BlockMass &BlockMass::operator*=(const BranchProbability &P) {
|
||||
uint32_t N = P.getNumerator(), D = P.getDenominator();
|
||||
assert(D && "divide by 0");
|
||||
assert(N <= D && "fraction greater than 1");
|
||||
|
||||
// Fast path for multiplying by 1.0.
|
||||
if (!Mass || N == D)
|
||||
return *this;
|
||||
|
||||
// Get as much precision as we can.
|
||||
int Shift = countLeadingZeros(Mass);
|
||||
uint64_t ShiftedQuotient = (Mass << Shift) / D;
|
||||
uint64_t Product = ShiftedQuotient * N >> Shift;
|
||||
|
||||
// Now check for what's lost.
|
||||
uint64_t Left = ShiftedQuotient * (D - N) >> Shift;
|
||||
uint64_t Lost = Mass - Product - Left;
|
||||
|
||||
// TODO: prove this assertion.
|
||||
assert(Lost <= UINT32_MAX);
|
||||
|
||||
// Take the product plus a portion of the spoils.
|
||||
Mass = Product + Lost * N / D;
|
||||
return *this;
|
||||
}
|
||||
|
||||
PositiveFloat<uint64_t> BlockMass::toFloat() const {
|
||||
if (isFull())
|
||||
return PositiveFloat<uint64_t>(1, 0);
|
||||
return PositiveFloat<uint64_t>(getMass() + 1, -64);
|
||||
}
|
||||
|
||||
void BlockMass::dump() const { print(dbgs()); }
|
||||
|
||||
static char getHexDigit(int N) {
|
||||
assert(N < 16);
|
||||
if (N < 10)
|
||||
return '0' + N;
|
||||
return 'a' + N - 10;
|
||||
}
|
||||
raw_ostream &BlockMass::print(raw_ostream &OS) const {
|
||||
for (int Digits = 0; Digits < 16; ++Digits)
|
||||
OS << getHexDigit(Mass >> (60 - Digits * 4) & 0xf);
|
||||
return OS;
|
||||
}
|
||||
|
||||
//===----------------------------------------------------------------------===//
|
||||
//
|
||||
// BlockFrequencyInfoImpl implementation.
|
||||
//
|
||||
//===----------------------------------------------------------------------===//
|
||||
namespace {
|
||||
|
||||
typedef BlockFrequencyInfoImplBase::BlockNode BlockNode;
|
||||
typedef BlockFrequencyInfoImplBase::Distribution Distribution;
|
||||
typedef BlockFrequencyInfoImplBase::Distribution::WeightList WeightList;
|
||||
typedef BlockFrequencyInfoImplBase::Float Float;
|
||||
typedef BlockFrequencyInfoImplBase::PackagedLoopData PackagedLoopData;
|
||||
typedef BlockFrequencyInfoImplBase::Weight Weight;
|
||||
typedef BlockFrequencyInfoImplBase::FrequencyData FrequencyData;
|
||||
|
||||
/// \brief Dithering mass distributer.
|
||||
///
|
||||
/// This class splits up a single mass into portions by weight, dithering to
|
||||
/// spread out error. No mass is lost. The dithering precision depends on the
|
||||
/// precision of the product of \a BlockMass and \a BranchProbability.
|
||||
///
|
||||
/// The distribution algorithm follows.
|
||||
///
|
||||
/// 1. Initialize by saving the sum of the weights in \a RemWeight and the
|
||||
/// mass to distribute in \a RemMass.
|
||||
///
|
||||
/// 2. For each portion:
|
||||
///
|
||||
/// 1. Construct a branch probability, P, as the portion's weight divided
|
||||
/// by the current value of \a RemWeight.
|
||||
/// 2. Calculate the portion's mass as \a RemMass times P.
|
||||
/// 3. Update \a RemWeight and \a RemMass at each portion by subtracting
|
||||
/// the current portion's weight and mass.
|
||||
///
|
||||
/// Mass is distributed in two ways: full distribution and forward
|
||||
/// distribution. The latter ignores backedges, and uses the parallel fields
|
||||
/// \a RemForwardWeight and \a RemForwardMass.
|
||||
struct DitheringDistributer {
|
||||
uint32_t RemWeight;
|
||||
uint32_t RemForwardWeight;
|
||||
|
||||
BlockMass RemMass;
|
||||
BlockMass RemForwardMass;
|
||||
|
||||
DitheringDistributer(Distribution &Dist, const BlockMass &Mass);
|
||||
|
||||
BlockMass takeLocalMass(uint32_t Weight) {
|
||||
(void)takeMass(Weight);
|
||||
return takeForwardMass(Weight);
|
||||
}
|
||||
BlockMass takeExitMass(uint32_t Weight) {
|
||||
(void)takeForwardMass(Weight);
|
||||
return takeMass(Weight);
|
||||
}
|
||||
BlockMass takeBackedgeMass(uint32_t Weight) { return takeMass(Weight); }
|
||||
|
||||
private:
|
||||
BlockMass takeForwardMass(uint32_t Weight);
|
||||
BlockMass takeMass(uint32_t Weight);
|
||||
};
|
||||
}
|
||||
|
||||
DitheringDistributer::DitheringDistributer(Distribution &Dist,
|
||||
const BlockMass &Mass) {
|
||||
Dist.normalize();
|
||||
RemWeight = Dist.Total;
|
||||
RemForwardWeight = Dist.ForwardTotal;
|
||||
RemMass = Mass;
|
||||
RemForwardMass = Dist.ForwardTotal ? Mass : BlockMass();
|
||||
}
|
||||
|
||||
BlockMass DitheringDistributer::takeForwardMass(uint32_t Weight) {
|
||||
// Compute the amount of mass to take.
|
||||
assert(Weight && "invalid weight");
|
||||
assert(Weight <= RemForwardWeight);
|
||||
BlockMass Mass = RemForwardMass * BranchProbability(Weight, RemForwardWeight);
|
||||
|
||||
// Decrement totals (dither).
|
||||
RemForwardWeight -= Weight;
|
||||
RemForwardMass -= Mass;
|
||||
return Mass;
|
||||
}
|
||||
BlockMass DitheringDistributer::takeMass(uint32_t Weight) {
|
||||
assert(Weight && "invalid weight");
|
||||
assert(Weight <= RemWeight);
|
||||
BlockMass Mass = RemMass * BranchProbability(Weight, RemWeight);
|
||||
|
||||
// Decrement totals (dither).
|
||||
RemWeight -= Weight;
|
||||
RemMass -= Mass;
|
||||
return Mass;
|
||||
}
|
||||
|
||||
void Distribution::add(const BlockNode &Node, uint64_t Amount,
|
||||
Weight::DistType Type) {
|
||||
assert(Amount && "invalid weight of 0");
|
||||
uint64_t NewTotal = Total + Amount;
|
||||
|
||||
// Check for overflow. It should be impossible to overflow twice.
|
||||
bool IsOverflow = NewTotal < Total;
|
||||
assert(!(DidOverflow && IsOverflow) && "unexpected repeated overflow");
|
||||
DidOverflow |= IsOverflow;
|
||||
|
||||
// Update the total.
|
||||
Total = NewTotal;
|
||||
|
||||
// Save the weight.
|
||||
Weight W;
|
||||
W.TargetNode = Node;
|
||||
W.Amount = Amount;
|
||||
W.Type = Type;
|
||||
Weights.push_back(W);
|
||||
|
||||
if (Type == Weight::Backedge)
|
||||
return;
|
||||
|
||||
// Update forward total. Don't worry about overflow here, since then Total
|
||||
// will exceed 32-bits and they'll both be recomputed in normalize().
|
||||
ForwardTotal += Amount;
|
||||
}
|
||||
|
||||
static void combineWeight(Weight &W, const Weight &OtherW) {
|
||||
assert(OtherW.TargetNode.isValid());
|
||||
if (!W.Amount) {
|
||||
W = OtherW;
|
||||
return;
|
||||
}
|
||||
assert(W.Type == OtherW.Type);
|
||||
assert(W.TargetNode == OtherW.TargetNode);
|
||||
assert(W.Amount < W.Amount + OtherW.Amount);
|
||||
W.Amount += OtherW.Amount;
|
||||
}
|
||||
static void combineWeightsBySorting(WeightList &Weights) {
|
||||
// Sort so edges to the same node are adjacent.
|
||||
std::sort(Weights.begin(), Weights.end(),
|
||||
[](const Weight &L,
|
||||
const Weight &R) { return L.TargetNode < R.TargetNode; });
|
||||
|
||||
// Combine adjacent edges.
|
||||
WeightList::iterator O = Weights.begin();
|
||||
for (WeightList::const_iterator I = O, L = O, E = Weights.end(); I != E;
|
||||
++O, (I = L)) {
|
||||
*O = *I;
|
||||
|
||||
// Find the adjacent weights to the same node.
|
||||
for (++L; L != E && I->TargetNode == L->TargetNode; ++L)
|
||||
combineWeight(*O, *L);
|
||||
}
|
||||
|
||||
// Erase extra entries.
|
||||
Weights.erase(O, Weights.end());
|
||||
return;
|
||||
}
|
||||
static void combineWeightsByHashing(WeightList &Weights) {
|
||||
// Collect weights into a DenseMap.
|
||||
typedef DenseMap<BlockNode::IndexType, Weight> HashTable;
|
||||
HashTable Combined(NextPowerOf2(2 * Weights.size()));
|
||||
for (const Weight &W : Weights)
|
||||
combineWeight(Combined[W.TargetNode.Index], W);
|
||||
|
||||
// Check whether anything changed.
|
||||
if (Weights.size() == Combined.size())
|
||||
return;
|
||||
|
||||
// Fill in the new weights.
|
||||
Weights.clear();
|
||||
Weights.reserve(Combined.size());
|
||||
for (const auto &I : Combined)
|
||||
Weights.push_back(I.second);
|
||||
}
|
||||
static void combineWeights(WeightList &Weights) {
|
||||
// Use a hash table for many successors to keep this linear.
|
||||
if (Weights.size() > 128) {
|
||||
combineWeightsByHashing(Weights);
|
||||
return;
|
||||
}
|
||||
|
||||
combineWeightsBySorting(Weights);
|
||||
}
|
||||
static uint64_t shiftRightAndRound(uint64_t N, int Shift) {
|
||||
assert(Shift >= 0);
|
||||
assert(Shift < 64);
|
||||
if (!Shift)
|
||||
return N;
|
||||
return (N >> Shift) + (UINT64_C(1) & N >> (Shift - 1));
|
||||
}
|
||||
void Distribution::normalize() {
|
||||
// Early exit for termination nodes.
|
||||
if (Weights.empty())
|
||||
return;
|
||||
|
||||
// Only bother if there are multiple successors.
|
||||
if (Weights.size() > 1)
|
||||
combineWeights(Weights);
|
||||
|
||||
// Early exit when combined into a single successor.
|
||||
if (Weights.size() == 1) {
|
||||
Total = 1;
|
||||
ForwardTotal = Weights.front().Type != Weight::Backedge;
|
||||
Weights.front().Amount = 1;
|
||||
return;
|
||||
}
|
||||
|
||||
// Determine how much to shift right so that the total fits into 32-bits.
|
||||
//
|
||||
// If we shift at all, shift by 1 extra. Otherwise, the lower limit of 1
|
||||
// for each weight can cause a 32-bit overflow.
|
||||
int Shift = 0;
|
||||
if (DidOverflow)
|
||||
Shift = 33;
|
||||
else if (Total > UINT32_MAX)
|
||||
Shift = 33 - countLeadingZeros(Total);
|
||||
|
||||
// Early exit if nothing needs to be scaled.
|
||||
if (!Shift)
|
||||
return;
|
||||
|
||||
// Recompute the total through accumulation (rather than shifting it) so that
|
||||
// it's accurate after shifting. ForwardTotal is dirty here anyway.
|
||||
Total = 0;
|
||||
ForwardTotal = 0;
|
||||
|
||||
// Sum the weights to each node and shift right if necessary.
|
||||
for (Weight &W : Weights) {
|
||||
// Scale down below UINT32_MAX. Since Shift is larger than necessary, we
|
||||
// can round here without concern about overflow.
|
||||
assert(W.TargetNode.isValid());
|
||||
W.Amount = std::max(UINT64_C(1), shiftRightAndRound(W.Amount, Shift));
|
||||
assert(W.Amount <= UINT32_MAX);
|
||||
|
||||
// Update the total.
|
||||
Total += W.Amount;
|
||||
if (W.Type == Weight::Backedge)
|
||||
continue;
|
||||
|
||||
// Update the forward total.
|
||||
ForwardTotal += W.Amount;
|
||||
}
|
||||
assert(Total <= UINT32_MAX);
|
||||
}
|
||||
|
||||
void BlockFrequencyInfoImplBase::clear() {
|
||||
*this = BlockFrequencyInfoImplBase();
|
||||
}
|
||||
|
||||
/// \brief Clear all memory not needed downstream.
|
||||
///
|
||||
/// Releases all memory not used downstream. In particular, saves Freqs.
|
||||
static void cleanup(BlockFrequencyInfoImplBase &BFI) {
|
||||
std::vector<FrequencyData> SavedFreqs(std::move(BFI.Freqs));
|
||||
BFI.clear();
|
||||
BFI.Freqs = std::move(SavedFreqs);
|
||||
}
|
||||
|
||||
/// \brief Get a possibly packaged node.
|
||||
///
|
||||
/// Get the node currently representing Node, which could be a containing
|
||||
/// loop.
|
||||
///
|
||||
/// This function should only be called when distributing mass. As long as
|
||||
/// there are no irreducilbe edges to Node, then it will have complexity O(1)
|
||||
/// in this context.
|
||||
///
|
||||
/// In general, the complexity is O(L), where L is the number of loop headers
|
||||
/// Node has been packaged into. Since this method is called in the context
|
||||
/// of distributing mass, L will be the number of loop headers an early exit
|
||||
/// edge jumps out of.
|
||||
static BlockNode getPackagedNode(const BlockFrequencyInfoImplBase &BFI,
|
||||
const BlockNode &Node) {
|
||||
assert(Node.isValid());
|
||||
if (!BFI.Working[Node.Index].IsPackaged)
|
||||
return Node;
|
||||
if (!BFI.Working[Node.Index].ContainingLoop.isValid())
|
||||
return Node;
|
||||
return getPackagedNode(BFI, BFI.Working[Node.Index].ContainingLoop);
|
||||
}
|
||||
|
||||
/// \brief Get the appropriate mass for a possible pseudo-node loop package.
|
||||
///
|
||||
/// Get appropriate mass for Node. If Node is a loop-header (whose loop has
|
||||
/// been packaged), returns the mass of its pseudo-node. If it's a node inside
|
||||
/// a packaged loop, it returns the loop's pseudo-node.
|
||||
static BlockMass &getPackageMass(BlockFrequencyInfoImplBase &BFI,
|
||||
const BlockNode &Node) {
|
||||
assert(Node.isValid());
|
||||
assert(!BFI.Working[Node.Index].IsPackaged);
|
||||
if (!BFI.Working[Node.Index].IsAPackage)
|
||||
return BFI.Working[Node.Index].Mass;
|
||||
|
||||
return BFI.getLoopPackage(Node).Mass;
|
||||
}
|
||||
|
||||
void BlockFrequencyInfoImplBase::addToDist(Distribution &Dist,
|
||||
const BlockNode &LoopHead,
|
||||
const BlockNode &Pred,
|
||||
const BlockNode &Succ,
|
||||
uint64_t Weight) {
|
||||
if (!Weight)
|
||||
Weight = 1;
|
||||
|
||||
#ifndef NDEBUG
|
||||
auto debugSuccessor = [&](const char *Type, const BlockNode &Resolved) {
|
||||
dbgs() << " =>"
|
||||
<< " [" << Type << "] weight = " << Weight;
|
||||
if (Succ != LoopHead)
|
||||
dbgs() << ", succ = " << getBlockName(Succ);
|
||||
if (Resolved != Succ)
|
||||
dbgs() << ", resolved = " << getBlockName(Resolved);
|
||||
dbgs() << "\n";
|
||||
};
|
||||
(void)debugSuccessor;
|
||||
#endif
|
||||
|
||||
if (Succ == LoopHead) {
|
||||
DEBUG(debugSuccessor("backedge", Succ));
|
||||
Dist.addBackedge(LoopHead, Weight);
|
||||
return;
|
||||
}
|
||||
BlockNode Resolved = getPackagedNode(*this, Succ);
|
||||
assert(Resolved != LoopHead);
|
||||
|
||||
if (Working[Resolved.Index].ContainingLoop != LoopHead) {
|
||||
DEBUG(debugSuccessor(" exit ", Resolved));
|
||||
Dist.addExit(Resolved, Weight);
|
||||
return;
|
||||
}
|
||||
|
||||
if (!LoopHead.isValid() && Resolved < Pred) {
|
||||
// Irreducible backedge. Skip this edge in the distribution.
|
||||
DEBUG(debugSuccessor("skipped ", Resolved));
|
||||
return;
|
||||
}
|
||||
|
||||
DEBUG(debugSuccessor(" local ", Resolved));
|
||||
Dist.addLocal(Resolved, Weight);
|
||||
}
|
||||
|
||||
void BlockFrequencyInfoImplBase::addLoopSuccessorsToDist(
|
||||
const BlockNode &LoopHead, const BlockNode &LocalLoopHead,
|
||||
Distribution &Dist) {
|
||||
PackagedLoopData &LoopPackage = getLoopPackage(LocalLoopHead);
|
||||
const PackagedLoopData::ExitMap &Exits = LoopPackage.Exits;
|
||||
|
||||
// Copy the exit map into Dist.
|
||||
for (const auto &I : Exits)
|
||||
addToDist(Dist, LoopHead, LocalLoopHead, I.first, I.second.getMass());
|
||||
|
||||
// We don't need this map any more. Clear it to prevent quadratic memory
|
||||
// usage in deeply nested loops with irreducible control flow.
|
||||
LoopPackage.Exits.clear();
|
||||
}
|
||||
|
||||
/// \brief Get the maximum allowed loop scale.
|
||||
///
|
||||
/// Gives the maximum number of estimated iterations allowed for a loop.
|
||||
/// Downstream users have trouble with very large numbers (even within
|
||||
/// 64-bits). Perhaps they can be changed to use PositiveFloat.
|
||||
///
|
||||
/// TODO: change downstream users so that this can be increased or removed.
|
||||
static Float getMaxLoopScale() { return Float(1, 12); }
|
||||
|
||||
/// \brief Compute the loop scale for a loop.
|
||||
void BlockFrequencyInfoImplBase::computeLoopScale(const BlockNode &LoopHead) {
|
||||
// Compute loop scale.
|
||||
DEBUG(dbgs() << "compute-loop-scale: " << getBlockName(LoopHead) << "\n");
|
||||
|
||||
// LoopScale == 1 / ExitMass
|
||||
// ExitMass == HeadMass - BackedgeMass
|
||||
PackagedLoopData &LoopPackage = getLoopPackage(LoopHead);
|
||||
BlockMass ExitMass = BlockMass::getFull() - LoopPackage.BackedgeMass;
|
||||
|
||||
// Block scale stores the inverse of the scale.
|
||||
LoopPackage.Scale = ExitMass.toFloat().inverse();
|
||||
|
||||
DEBUG(dbgs() << " - exit-mass = " << ExitMass << " (" << BlockMass::getFull()
|
||||
<< " - " << LoopPackage.BackedgeMass << ")\n"
|
||||
<< " - scale = " << LoopPackage.Scale << "\n");
|
||||
|
||||
if (LoopPackage.Scale > getMaxLoopScale()) {
|
||||
LoopPackage.Scale = getMaxLoopScale();
|
||||
DEBUG(dbgs() << " - reduced-to-max-scale: " << getMaxLoopScale() << "\n");
|
||||
}
|
||||
}
|
||||
|
||||
/// \brief Package up a loop.
|
||||
void BlockFrequencyInfoImplBase::packageLoop(const BlockNode &LoopHead) {
|
||||
DEBUG(dbgs() << "packaging-loop: " << getBlockName(LoopHead) << "\n");
|
||||
Working[LoopHead.Index].IsAPackage = true;
|
||||
for (const BlockNode &M : getLoopPackage(LoopHead).Members) {
|
||||
DEBUG(dbgs() << " - node: " << getBlockName(M.Index) << "\n");
|
||||
Working[M.Index].IsPackaged = true;
|
||||
}
|
||||
}
|
||||
|
||||
void BlockFrequencyInfoImplBase::distributeMass(const BlockNode &Source,
|
||||
const BlockNode &LoopHead,
|
||||
Distribution &Dist) {
|
||||
BlockMass Mass = getPackageMass(*this, Source);
|
||||
DEBUG(dbgs() << " => mass: " << Mass
|
||||
<< " ( general | forward )\n");
|
||||
|
||||
// Distribute mass to successors as laid out in Dist.
|
||||
DitheringDistributer D(Dist, Mass);
|
||||
|
||||
#ifndef NDEBUG
|
||||
auto debugAssign = [&](const BlockNode &T, const BlockMass &M,
|
||||
const char *Desc) {
|
||||
dbgs() << " => assign " << M << " (" << D.RemMass << "|"
|
||||
<< D.RemForwardMass << ")";
|
||||
if (Desc)
|
||||
dbgs() << " [" << Desc << "]";
|
||||
if (T.isValid())
|
||||
dbgs() << " to " << getBlockName(T);
|
||||
dbgs() << "\n";
|
||||
};
|
||||
(void)debugAssign;
|
||||
#endif
|
||||
|
||||
PackagedLoopData *LoopPackage = 0;
|
||||
if (LoopHead.isValid())
|
||||
LoopPackage = &getLoopPackage(LoopHead);
|
||||
for (const Weight &W : Dist.Weights) {
|
||||
// Check for a local edge (forward and non-exit).
|
||||
if (W.Type == Weight::Local) {
|
||||
BlockMass Local = D.takeLocalMass(W.Amount);
|
||||
getPackageMass(*this, W.TargetNode) += Local;
|
||||
DEBUG(debugAssign(W.TargetNode, Local, nullptr));
|
||||
continue;
|
||||
}
|
||||
|
||||
// Backedges and exits only make sense if we're processing a loop.
|
||||
assert(LoopPackage && "backedge or exit outside of loop");
|
||||
|
||||
// Check for a backedge.
|
||||
if (W.Type == Weight::Backedge) {
|
||||
BlockMass Back = D.takeBackedgeMass(W.Amount);
|
||||
LoopPackage->BackedgeMass += Back;
|
||||
DEBUG(debugAssign(BlockNode(), Back, "back"));
|
||||
continue;
|
||||
}
|
||||
|
||||
// This must be an exit.
|
||||
assert(W.Type == Weight::Exit);
|
||||
BlockMass Exit = D.takeExitMass(W.Amount);
|
||||
LoopPackage->Exits.push_back(std::make_pair(W.TargetNode, Exit));
|
||||
DEBUG(debugAssign(W.TargetNode, Exit, "exit"));
|
||||
}
|
||||
}
|
||||
|
||||
static void convertFloatingToInteger(BlockFrequencyInfoImplBase &BFI,
|
||||
const Float &Min, const Float &Max) {
|
||||
// Scale the Factor to a size that creates integers. Ideally, integers would
|
||||
// be scaled so that Max == UINT64_MAX so that they can be best
|
||||
// differentiated. However, the register allocator currently deals poorly
|
||||
// with large numbers. Instead, push Min up a little from 1 to give some
|
||||
// room to differentiate small, unequal numbers.
|
||||
//
|
||||
// TODO: fix issues downstream so that ScalingFactor can be Float(1,64)/Max.
|
||||
Float ScalingFactor = Min.inverse();
|
||||
if ((Max / Min).lg() < 60)
|
||||
ScalingFactor <<= 3;
|
||||
|
||||
// Translate the floats to integers.
|
||||
DEBUG(dbgs() << "float-to-int: min = " << Min << ", max = " << Max
|
||||
<< ", factor = " << ScalingFactor << "\n");
|
||||
for (size_t Index = 0; Index < BFI.Freqs.size(); ++Index) {
|
||||
Float Scaled = BFI.Freqs[Index].Floating * ScalingFactor;
|
||||
BFI.Freqs[Index].Integer = std::max(UINT64_C(1), Scaled.toInt<uint64_t>());
|
||||
DEBUG(dbgs() << " - " << BFI.getBlockName(Index) << ": float = "
|
||||
<< BFI.Freqs[Index].Floating << ", scaled = " << Scaled
|
||||
<< ", int = " << BFI.Freqs[Index].Integer << "\n");
|
||||
}
|
||||
}
|
||||
|
||||
static void scaleBlockData(BlockFrequencyInfoImplBase &BFI,
|
||||
const BlockNode &Node,
|
||||
const PackagedLoopData &Loop) {
|
||||
Float F = Loop.Mass.toFloat() * Loop.Scale;
|
||||
|
||||
Float &Current = BFI.Freqs[Node.Index].Floating;
|
||||
Float Updated = Current * F;
|
||||
|
||||
DEBUG(dbgs() << " - " << BFI.getBlockName(Node) << ": " << Current << " => "
|
||||
<< Updated << "\n");
|
||||
|
||||
Current = Updated;
|
||||
}
|
||||
|
||||
/// \brief Unwrap a loop package.
|
||||
///
|
||||
/// Visits all the members of a loop, adjusting their BlockData according to
|
||||
/// the loop's pseudo-node.
|
||||
static void unwrapLoopPackage(BlockFrequencyInfoImplBase &BFI,
|
||||
const BlockNode &Head) {
|
||||
assert(Head.isValid());
|
||||
|
||||
PackagedLoopData &LoopPackage = BFI.getLoopPackage(Head);
|
||||
DEBUG(dbgs() << "unwrap-loop-package: " << BFI.getBlockName(Head)
|
||||
<< ": mass = " << LoopPackage.Mass
|
||||
<< ", scale = " << LoopPackage.Scale << "\n");
|
||||
scaleBlockData(BFI, Head, LoopPackage);
|
||||
|
||||
// Propagate the head scale through the loop. Since members are visited in
|
||||
// RPO, the head scale will be updated by the loop scale first, and then the
|
||||
// final head scale will be used for updated the rest of the members.
|
||||
for (const BlockNode &M : LoopPackage.Members) {
|
||||
const FrequencyData &HeadData = BFI.Freqs[Head.Index];
|
||||
FrequencyData &Freqs = BFI.Freqs[M.Index];
|
||||
Float NewFreq = Freqs.Floating * HeadData.Floating;
|
||||
DEBUG(dbgs() << " - " << BFI.getBlockName(M) << ": " << Freqs.Floating
|
||||
<< " => " << NewFreq << "\n");
|
||||
Freqs.Floating = NewFreq;
|
||||
}
|
||||
}
|
||||
|
||||
void BlockFrequencyInfoImplBase::finalizeMetrics() {
|
||||
// Set initial frequencies from loop-local masses.
|
||||
for (size_t Index = 0; Index < Working.size(); ++Index)
|
||||
Freqs[Index].Floating = Working[Index].Mass.toFloat();
|
||||
|
||||
// Unwrap loop packages in reverse post-order, tracking min and max
|
||||
// frequencies.
|
||||
auto Min = Float::getLargest();
|
||||
auto Max = Float::getZero();
|
||||
for (size_t Index = 0; Index < Working.size(); ++Index) {
|
||||
if (Working[Index].isLoopHeader())
|
||||
unwrapLoopPackage(*this, BlockNode(Index));
|
||||
|
||||
// Update max scale.
|
||||
Min = std::min(Min, Freqs[Index].Floating);
|
||||
Max = std::max(Max, Freqs[Index].Floating);
|
||||
}
|
||||
|
||||
// Convert to integers.
|
||||
convertFloatingToInteger(*this, Min, Max);
|
||||
|
||||
// Clean up data structures.
|
||||
cleanup(*this);
|
||||
|
||||
// Print out the final stats.
|
||||
DEBUG(dump());
|
||||
}
|
||||
|
||||
BlockFrequency
|
||||
BlockFrequencyInfoImplBase::getBlockFreq(const BlockNode &Node) const {
|
||||
if (!Node.isValid())
|
||||
return 0;
|
||||
return Freqs[Node.Index].Integer;
|
||||
}
|
||||
Float
|
||||
BlockFrequencyInfoImplBase::getFloatingBlockFreq(const BlockNode &Node) const {
|
||||
if (!Node.isValid())
|
||||
return Float::getZero();
|
||||
return Freqs[Node.Index].Floating;
|
||||
}
|
||||
|
||||
std::string
|
||||
BlockFrequencyInfoImplBase::getBlockName(const BlockNode &Node) const {
|
||||
return std::string();
|
||||
}
|
||||
|
||||
raw_ostream &
|
||||
BlockFrequencyInfoImplBase::printBlockFreq(raw_ostream &OS,
|
||||
const BlockNode &Node) const {
|
||||
return OS << getFloatingBlockFreq(Node);
|
||||
}
|
||||
|
||||
raw_ostream &
|
||||
BlockFrequencyInfoImplBase::printBlockFreq(raw_ostream &OS,
|
||||
const BlockFrequency &Freq) const {
|
||||
Float Block(Freq.getFrequency(), 0);
|
||||
Float Entry(getEntryFreq(), 0);
|
||||
|
||||
return OS << Block / Entry;
|
||||
}
|
||||
@@ -7,6 +7,7 @@ add_llvm_library(LLVMAnalysis
|
||||
Analysis.cpp
|
||||
BasicAliasAnalysis.cpp
|
||||
BlockFrequencyInfo.cpp
|
||||
BlockFrequencyInfoImpl.cpp
|
||||
BranchProbabilityInfo.cpp
|
||||
CFG.cpp
|
||||
CFGPrinter.cpp
|
||||
|
||||
@@ -11,9 +11,12 @@
|
||||
//
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
#define DEBUG_TYPE "block-freq"
|
||||
#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
|
||||
#include "llvm/Analysis/BlockFrequencyInfoImpl.h"
|
||||
#include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
|
||||
#include "llvm/CodeGen/MachineFunction.h"
|
||||
#include "llvm/CodeGen/MachineLoopInfo.h"
|
||||
#include "llvm/CodeGen/Passes.h"
|
||||
#include "llvm/InitializePasses.h"
|
||||
#include "llvm/Support/CommandLine.h"
|
||||
@@ -112,6 +115,7 @@ struct DOTGraphTraits<MachineBlockFrequencyInfo*> :
|
||||
INITIALIZE_PASS_BEGIN(MachineBlockFrequencyInfo, "machine-block-freq",
|
||||
"Machine Block Frequency Analysis", true, true)
|
||||
INITIALIZE_PASS_DEPENDENCY(MachineBranchProbabilityInfo)
|
||||
INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
|
||||
INITIALIZE_PASS_END(MachineBlockFrequencyInfo, "machine-block-freq",
|
||||
"Machine Block Frequency Analysis", true, true)
|
||||
|
||||
@@ -127,6 +131,7 @@ MachineBlockFrequencyInfo::~MachineBlockFrequencyInfo() {}
|
||||
|
||||
void MachineBlockFrequencyInfo::getAnalysisUsage(AnalysisUsage &AU) const {
|
||||
AU.addRequired<MachineBranchProbabilityInfo>();
|
||||
AU.addRequired<MachineLoopInfo>();
|
||||
AU.setPreservesAll();
|
||||
MachineFunctionPass::getAnalysisUsage(AU);
|
||||
}
|
||||
@@ -134,9 +139,10 @@ void MachineBlockFrequencyInfo::getAnalysisUsage(AnalysisUsage &AU) const {
|
||||
bool MachineBlockFrequencyInfo::runOnMachineFunction(MachineFunction &F) {
|
||||
MachineBranchProbabilityInfo &MBPI =
|
||||
getAnalysis<MachineBranchProbabilityInfo>();
|
||||
MachineLoopInfo &MLI = getAnalysis<MachineLoopInfo>();
|
||||
if (!MBFI)
|
||||
MBFI.reset(new ImplType);
|
||||
MBFI->doFunction(&F, &MBPI);
|
||||
MBFI->doFunction(&F, &MBPI, &MLI);
|
||||
#ifndef NDEBUG
|
||||
if (ViewMachineBlockFreqPropagationDAG != GVDT_None) {
|
||||
view();
|
||||
@@ -166,7 +172,7 @@ getBlockFreq(const MachineBasicBlock *MBB) const {
|
||||
}
|
||||
|
||||
const MachineFunction *MachineBlockFrequencyInfo::getFunction() const {
|
||||
return MBFI ? MBFI->Fn : nullptr;
|
||||
return MBFI ? MBFI->getFunction() : nullptr;
|
||||
}
|
||||
|
||||
raw_ostream &
|
||||
|
||||
50
test/Analysis/BlockFrequencyInfo/bad_input.ll
Normal file
50
test/Analysis/BlockFrequencyInfo/bad_input.ll
Normal file
@@ -0,0 +1,50 @@
|
||||
; RUN: opt < %s -analyze -block-freq | FileCheck %s
|
||||
|
||||
declare void @g(i32 %x)
|
||||
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'branch_weight_0':
|
||||
; CHECK-NEXT: block-frequency-info: branch_weight_0
|
||||
define void @branch_weight_0(i32 %a) {
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
br label %for.body
|
||||
|
||||
; Check that we get 1,4 instead of 0,3.
|
||||
; CHECK-NEXT: for.body: float = 4.0,
|
||||
for.body:
|
||||
%i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
|
||||
call void @g(i32 %i)
|
||||
%inc = add i32 %i, 1
|
||||
%cmp = icmp ugt i32 %inc, %a
|
||||
br i1 %cmp, label %for.end, label %for.body, !prof !0
|
||||
|
||||
; CHECK-NEXT: for.end: float = 1.0, int = [[ENTRY]]
|
||||
for.end:
|
||||
ret void
|
||||
}
|
||||
|
||||
!0 = metadata !{metadata !"branch_weights", i32 0, i32 3}
|
||||
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'infinite_loop'
|
||||
; CHECK-NEXT: block-frequency-info: infinite_loop
|
||||
define void @infinite_loop(i1 %x) {
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
br i1 %x, label %for.body, label %for.end, !prof !1
|
||||
|
||||
; Check that the loop scale maxes out at 4096, giving 2048 here.
|
||||
; CHECK-NEXT: for.body: float = 2048.0,
|
||||
for.body:
|
||||
%i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
|
||||
call void @g(i32 %i)
|
||||
%inc = add i32 %i, 1
|
||||
br label %for.body
|
||||
|
||||
; Check that the exit weight is half of entry, since half is lost in the
|
||||
; infinite loop above.
|
||||
; CHECK-NEXT: for.end: float = 0.5,
|
||||
for.end:
|
||||
ret void
|
||||
}
|
||||
|
||||
!1 = metadata !{metadata !"branch_weights", i32 1, i32 1}
|
||||
@@ -1,13 +1,14 @@
|
||||
; RUN: opt < %s -analyze -block-freq | FileCheck %s
|
||||
|
||||
define i32 @test1(i32 %i, i32* %a) {
|
||||
; CHECK: Printing analysis {{.*}} for function 'test1'
|
||||
; CHECK: entry = 1.0
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'test1':
|
||||
; CHECK-NEXT: block-frequency-info: test1
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
br label %body
|
||||
|
||||
; Loop backedges are weighted and thus their bodies have a greater frequency.
|
||||
; CHECK: body = 32.0
|
||||
; CHECK-NEXT: body: float = 32.0,
|
||||
body:
|
||||
%iv = phi i32 [ 0, %entry ], [ %next, %body ]
|
||||
%base = phi i32 [ 0, %entry ], [ %sum, %body ]
|
||||
@@ -18,29 +19,29 @@ body:
|
||||
%exitcond = icmp eq i32 %next, %i
|
||||
br i1 %exitcond, label %exit, label %body
|
||||
|
||||
; CHECK: exit = 1.0
|
||||
; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
|
||||
exit:
|
||||
ret i32 %sum
|
||||
}
|
||||
|
||||
define i32 @test2(i32 %i, i32 %a, i32 %b) {
|
||||
; CHECK: Printing analysis {{.*}} for function 'test2'
|
||||
; CHECK: entry = 1.0
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'test2':
|
||||
; CHECK-NEXT: block-frequency-info: test2
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
%cond = icmp ult i32 %i, 42
|
||||
br i1 %cond, label %then, label %else, !prof !0
|
||||
|
||||
; The 'then' branch is predicted more likely via branch weight metadata.
|
||||
; CHECK: then = 0.94116
|
||||
; CHECK-NEXT: then: float = 0.9411{{[0-9]*}},
|
||||
then:
|
||||
br label %exit
|
||||
|
||||
; CHECK: else = 0.05877
|
||||
; CHECK-NEXT: else: float = 0.05882{{[0-9]*}},
|
||||
else:
|
||||
br label %exit
|
||||
|
||||
; FIXME: It may be a bug that we don't sum back to 1.0.
|
||||
; CHECK: exit = 0.99993
|
||||
; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
|
||||
exit:
|
||||
%result = phi i32 [ %a, %then ], [ %b, %else ]
|
||||
ret i32 %result
|
||||
@@ -49,37 +50,37 @@ exit:
|
||||
!0 = metadata !{metadata !"branch_weights", i32 64, i32 4}
|
||||
|
||||
define i32 @test3(i32 %i, i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) {
|
||||
; CHECK: Printing analysis {{.*}} for function 'test3'
|
||||
; CHECK: entry = 1.0
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'test3':
|
||||
; CHECK-NEXT: block-frequency-info: test3
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
switch i32 %i, label %case_a [ i32 1, label %case_b
|
||||
i32 2, label %case_c
|
||||
i32 3, label %case_d
|
||||
i32 4, label %case_e ], !prof !1
|
||||
|
||||
; CHECK: case_a = 0.04998
|
||||
; CHECK-NEXT: case_a: float = 0.05,
|
||||
case_a:
|
||||
br label %exit
|
||||
|
||||
; CHECK: case_b = 0.04998
|
||||
; CHECK-NEXT: case_b: float = 0.05,
|
||||
case_b:
|
||||
br label %exit
|
||||
|
||||
; The 'case_c' branch is predicted more likely via branch weight metadata.
|
||||
; CHECK: case_c = 0.79998
|
||||
; CHECK-NEXT: case_c: float = 0.8,
|
||||
case_c:
|
||||
br label %exit
|
||||
|
||||
; CHECK: case_d = 0.04998
|
||||
; CHECK-NEXT: case_d: float = 0.05,
|
||||
case_d:
|
||||
br label %exit
|
||||
|
||||
; CHECK: case_e = 0.04998
|
||||
; CHECK-NEXT: case_e: float = 0.05,
|
||||
case_e:
|
||||
br label %exit
|
||||
|
||||
; FIXME: It may be a bug that we don't sum back to 1.0.
|
||||
; CHECK: exit = 0.99993
|
||||
; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
|
||||
exit:
|
||||
%result = phi i32 [ %a, %case_a ],
|
||||
[ %b, %case_b ],
|
||||
@@ -91,44 +92,50 @@ exit:
|
||||
|
||||
!1 = metadata !{metadata !"branch_weights", i32 4, i32 4, i32 64, i32 4, i32 4}
|
||||
|
||||
; CHECK: Printing analysis {{.*}} for function 'nested_loops'
|
||||
; CHECK: entry = 1.0
|
||||
; This test doesn't seem to be assigning sensible frequencies to nested loops.
|
||||
define void @nested_loops(i32 %a) {
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'nested_loops':
|
||||
; CHECK-NEXT: block-frequency-info: nested_loops
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
br label %for.cond1.preheader
|
||||
|
||||
; CHECK-NEXT: for.cond1.preheader: float = 4001.0,
|
||||
for.cond1.preheader:
|
||||
%x.024 = phi i32 [ 0, %entry ], [ %inc12, %for.inc11 ]
|
||||
br label %for.cond4.preheader
|
||||
|
||||
; CHECK-NEXT: for.cond4.preheader: float = 16008001.0,
|
||||
for.cond4.preheader:
|
||||
%y.023 = phi i32 [ 0, %for.cond1.preheader ], [ %inc9, %for.inc8 ]
|
||||
%add = add i32 %y.023, %x.024
|
||||
br label %for.body6
|
||||
|
||||
; CHECK-NEXT: for.body6: float = 64048012001.0,
|
||||
for.body6:
|
||||
%z.022 = phi i32 [ 0, %for.cond4.preheader ], [ %inc, %for.body6 ]
|
||||
%add7 = add i32 %add, %z.022
|
||||
tail call void @g(i32 %add7) #2
|
||||
tail call void @g(i32 %add7)
|
||||
%inc = add i32 %z.022, 1
|
||||
%cmp5 = icmp ugt i32 %inc, %a
|
||||
br i1 %cmp5, label %for.inc8, label %for.body6, !prof !2
|
||||
|
||||
; CHECK-NEXT: for.inc8: float = 16008001.0,
|
||||
for.inc8:
|
||||
%inc9 = add i32 %y.023, 1
|
||||
%cmp2 = icmp ugt i32 %inc9, %a
|
||||
br i1 %cmp2, label %for.inc11, label %for.cond4.preheader, !prof !2
|
||||
|
||||
; CHECK-NEXT: for.inc11: float = 4001.0,
|
||||
for.inc11:
|
||||
%inc12 = add i32 %x.024, 1
|
||||
%cmp = icmp ugt i32 %inc12, %a
|
||||
br i1 %cmp, label %for.end13, label %for.cond1.preheader, !prof !2
|
||||
|
||||
; CHECK-NEXT: for.end13: float = 1.0, int = [[ENTRY]]
|
||||
for.end13:
|
||||
ret void
|
||||
}
|
||||
|
||||
declare void @g(i32) #1
|
||||
declare void @g(i32)
|
||||
|
||||
!2 = metadata !{metadata !"branch_weights", i32 1, i32 4000}
|
||||
|
||||
165
test/Analysis/BlockFrequencyInfo/double_exit.ll
Normal file
165
test/Analysis/BlockFrequencyInfo/double_exit.ll
Normal file
@@ -0,0 +1,165 @@
|
||||
; RUN: opt < %s -analyze -block-freq | FileCheck %s
|
||||
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'double_exit':
|
||||
; CHECK-NEXT: block-frequency-info: double_exit
|
||||
define i32 @double_exit(i32 %N) {
|
||||
; Mass = 1
|
||||
; Frequency = 1
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
br label %outer
|
||||
|
||||
; Mass = 1
|
||||
; Backedge mass = 1/3, exit mass = 2/3
|
||||
; Loop scale = 3/2
|
||||
; Psuedo-edges = exit
|
||||
; Psuedo-mass = 1
|
||||
; Frequency = 1*3/2*1 = 3/2
|
||||
; CHECK-NEXT: outer: float = 1.5,
|
||||
outer:
|
||||
%I.0 = phi i32 [ 0, %entry ], [ %inc6, %outer.inc ]
|
||||
%Return.0 = phi i32 [ 0, %entry ], [ %Return.1, %outer.inc ]
|
||||
%cmp = icmp slt i32 %I.0, %N
|
||||
br i1 %cmp, label %inner, label %exit, !prof !2 ; 2:1
|
||||
|
||||
; Mass = 1
|
||||
; Backedge mass = 3/5, exit mass = 2/5
|
||||
; Loop scale = 5/2
|
||||
; Pseudo-edges = outer.inc @ 1/5, exit @ 1/5
|
||||
; Pseudo-mass = 2/3
|
||||
; Frequency = 3/2*1*5/2*2/3 = 5/2
|
||||
; CHECK-NEXT: inner: float = 2.5,
|
||||
inner:
|
||||
%Return.1 = phi i32 [ %Return.0, %outer ], [ %call4, %inner.inc ]
|
||||
%J.0 = phi i32 [ %I.0, %outer ], [ %inc, %inner.inc ]
|
||||
%cmp2 = icmp slt i32 %J.0, %N
|
||||
br i1 %cmp2, label %inner.body, label %outer.inc, !prof !1 ; 4:1
|
||||
|
||||
; Mass = 4/5
|
||||
; Frequency = 5/2*4/5 = 2
|
||||
; CHECK-NEXT: inner.body: float = 2.0,
|
||||
inner.body:
|
||||
%call = call i32 @c2(i32 %I.0, i32 %J.0)
|
||||
%tobool = icmp ne i32 %call, 0
|
||||
br i1 %tobool, label %exit, label %inner.inc, !prof !0 ; 3:1
|
||||
|
||||
; Mass = 3/5
|
||||
; Frequency = 5/2*3/5 = 3/2
|
||||
; CHECK-NEXT: inner.inc: float = 1.5,
|
||||
inner.inc:
|
||||
%call4 = call i32 @logic2(i32 %Return.1, i32 %I.0, i32 %J.0)
|
||||
%inc = add nsw i32 %J.0, 1
|
||||
br label %inner
|
||||
|
||||
; Mass = 1/3
|
||||
; Frequency = 3/2*1/3 = 1/2
|
||||
; CHECK-NEXT: outer.inc: float = 0.5,
|
||||
outer.inc:
|
||||
%inc6 = add nsw i32 %I.0, 1
|
||||
br label %outer
|
||||
|
||||
; Mass = 1
|
||||
; Frequency = 1
|
||||
; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
|
||||
exit:
|
||||
%Return.2 = phi i32 [ %Return.1, %inner.body ], [ %Return.0, %outer ]
|
||||
ret i32 %Return.2
|
||||
}
|
||||
|
||||
!0 = metadata !{metadata !"branch_weights", i32 1, i32 3}
|
||||
!1 = metadata !{metadata !"branch_weights", i32 4, i32 1}
|
||||
!2 = metadata !{metadata !"branch_weights", i32 2, i32 1}
|
||||
|
||||
declare i32 @c2(i32, i32)
|
||||
declare i32 @logic2(i32, i32, i32)
|
||||
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'double_exit_in_loop':
|
||||
; CHECK-NEXT: block-frequency-info: double_exit_in_loop
|
||||
define i32 @double_exit_in_loop(i32 %N) {
|
||||
; Mass = 1
|
||||
; Frequency = 1
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
br label %outer
|
||||
|
||||
; Mass = 1
|
||||
; Backedge mass = 1/2, exit mass = 1/2
|
||||
; Loop scale = 2
|
||||
; Pseudo-edges = exit
|
||||
; Psuedo-mass = 1
|
||||
; Frequency = 1*2*1 = 2
|
||||
; CHECK-NEXT: outer: float = 2.0,
|
||||
outer:
|
||||
%I.0 = phi i32 [ 0, %entry ], [ %inc12, %outer.inc ]
|
||||
%Return.0 = phi i32 [ 0, %entry ], [ %Return.3, %outer.inc ]
|
||||
%cmp = icmp slt i32 %I.0, %N
|
||||
br i1 %cmp, label %middle, label %exit, !prof !3 ; 1:1
|
||||
|
||||
; Mass = 1
|
||||
; Backedge mass = 1/3, exit mass = 2/3
|
||||
; Loop scale = 3/2
|
||||
; Psuedo-edges = outer.inc
|
||||
; Psuedo-mass = 1/2
|
||||
; Frequency = 2*1*3/2*1/2 = 3/2
|
||||
; CHECK-NEXT: middle: float = 1.5,
|
||||
middle:
|
||||
%J.0 = phi i32 [ %I.0, %outer ], [ %inc9, %middle.inc ]
|
||||
%Return.1 = phi i32 [ %Return.0, %outer ], [ %Return.2, %middle.inc ]
|
||||
%cmp2 = icmp slt i32 %J.0, %N
|
||||
br i1 %cmp2, label %inner, label %outer.inc, !prof !2 ; 2:1
|
||||
|
||||
; Mass = 1
|
||||
; Backedge mass = 3/5, exit mass = 2/5
|
||||
; Loop scale = 5/2
|
||||
; Pseudo-edges = middle.inc @ 1/5, outer.inc @ 1/5
|
||||
; Pseudo-mass = 2/3
|
||||
; Frequency = 3/2*1*5/2*2/3 = 5/2
|
||||
; CHECK-NEXT: inner: float = 2.5,
|
||||
inner:
|
||||
%Return.2 = phi i32 [ %Return.1, %middle ], [ %call7, %inner.inc ]
|
||||
%K.0 = phi i32 [ %J.0, %middle ], [ %inc, %inner.inc ]
|
||||
%cmp5 = icmp slt i32 %K.0, %N
|
||||
br i1 %cmp5, label %inner.body, label %middle.inc, !prof !1 ; 4:1
|
||||
|
||||
; Mass = 4/5
|
||||
; Frequency = 5/2*4/5 = 2
|
||||
; CHECK-NEXT: inner.body: float = 2.0,
|
||||
inner.body:
|
||||
%call = call i32 @c3(i32 %I.0, i32 %J.0, i32 %K.0)
|
||||
%tobool = icmp ne i32 %call, 0
|
||||
br i1 %tobool, label %outer.inc, label %inner.inc, !prof !0 ; 3:1
|
||||
|
||||
; Mass = 3/5
|
||||
; Frequency = 5/2*3/5 = 3/2
|
||||
; CHECK-NEXT: inner.inc: float = 1.5,
|
||||
inner.inc:
|
||||
%call7 = call i32 @logic3(i32 %Return.2, i32 %I.0, i32 %J.0, i32 %K.0)
|
||||
%inc = add nsw i32 %K.0, 1
|
||||
br label %inner
|
||||
|
||||
; Mass = 1/3
|
||||
; Frequency = 3/2*1/3 = 1/2
|
||||
; CHECK-NEXT: middle.inc: float = 0.5,
|
||||
middle.inc:
|
||||
%inc9 = add nsw i32 %J.0, 1
|
||||
br label %middle
|
||||
|
||||
; Mass = 1/2
|
||||
; Frequency = 2*1/2 = 1
|
||||
; CHECK-NEXT: outer.inc: float = 1.0,
|
||||
outer.inc:
|
||||
%Return.3 = phi i32 [ %Return.2, %inner.body ], [ %Return.1, %middle ]
|
||||
%inc12 = add nsw i32 %I.0, 1
|
||||
br label %outer
|
||||
|
||||
; Mass = 1
|
||||
; Frequency = 1
|
||||
; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
|
||||
exit:
|
||||
ret i32 %Return.0
|
||||
}
|
||||
|
||||
!3 = metadata !{metadata !"branch_weights", i32 1, i32 1}
|
||||
|
||||
declare i32 @c3(i32, i32, i32)
|
||||
declare i32 @logic3(i32, i32, i32, i32)
|
||||
197
test/Analysis/BlockFrequencyInfo/irreducible.ll
Normal file
197
test/Analysis/BlockFrequencyInfo/irreducible.ll
Normal file
@@ -0,0 +1,197 @@
|
||||
; RUN: opt < %s -analyze -block-freq | FileCheck %s
|
||||
|
||||
; A loop with multiple exits should be handled correctly.
|
||||
;
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'multiexit':
|
||||
; CHECK-NEXT: block-frequency-info: multiexit
|
||||
define void @multiexit(i32 %a) {
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
br label %loop.1
|
||||
|
||||
; CHECK-NEXT: loop.1: float = 1.333{{3*}},
|
||||
loop.1:
|
||||
%i = phi i32 [ 0, %entry ], [ %inc.2, %loop.2 ]
|
||||
call void @f(i32 %i)
|
||||
%inc.1 = add i32 %i, 1
|
||||
%cmp.1 = icmp ugt i32 %inc.1, %a
|
||||
br i1 %cmp.1, label %exit.1, label %loop.2, !prof !0
|
||||
|
||||
; CHECK-NEXT: loop.2: float = 0.666{{6*7}},
|
||||
loop.2:
|
||||
call void @g(i32 %inc.1)
|
||||
%inc.2 = add i32 %inc.1, 1
|
||||
%cmp.2 = icmp ugt i32 %inc.2, %a
|
||||
br i1 %cmp.2, label %exit.2, label %loop.1, !prof !1
|
||||
|
||||
; CHECK-NEXT: exit.1: float = 0.666{{6*7}},
|
||||
exit.1:
|
||||
call void @h(i32 %inc.1)
|
||||
br label %return
|
||||
|
||||
; CHECK-NEXT: exit.2: float = 0.333{{3*}},
|
||||
exit.2:
|
||||
call void @i(i32 %inc.2)
|
||||
br label %return
|
||||
|
||||
; CHECK-NEXT: return: float = 1.0, int = [[ENTRY]]
|
||||
return:
|
||||
ret void
|
||||
}
|
||||
|
||||
declare void @f(i32 %x)
|
||||
declare void @g(i32 %x)
|
||||
declare void @h(i32 %x)
|
||||
declare void @i(i32 %x)
|
||||
|
||||
!0 = metadata !{metadata !"branch_weights", i32 3, i32 3}
|
||||
!1 = metadata !{metadata !"branch_weights", i32 5, i32 5}
|
||||
|
||||
; The current BlockFrequencyInfo algorithm doesn't handle multiple entrances
|
||||
; into a loop very well. The frequencies assigned to blocks in the loop are
|
||||
; predictable (and not absurd), but also not correct and therefore not worth
|
||||
; testing.
|
||||
;
|
||||
; There are two testcases below.
|
||||
;
|
||||
; For each testcase, I use a CHECK-NEXT/NOT combo like an XFAIL with the
|
||||
; granularity of a single check. If/when this behaviour is fixed, we'll know
|
||||
; about it, and the test should be updated.
|
||||
;
|
||||
; Testcase #1
|
||||
; ===========
|
||||
;
|
||||
; In this case c1 and c2 should have frequencies of 15/7 and 13/7,
|
||||
; respectively. To calculate this, consider assigning 1.0 to entry, and
|
||||
; distributing frequency iteratively (to infinity). At the first iteration,
|
||||
; entry gives 3/4 to c1 and 1/4 to c2. At every step after, c1 and c2 give 3/4
|
||||
; of what they have to each other. Somehow, all of it comes out to exit.
|
||||
;
|
||||
; c1 = 3/4 + 1/4*3/4 + 3/4*3^2/4^2 + 1/4*3^3/4^3 + 3/4*3^3/4^3 + ...
|
||||
; c2 = 1/4 + 3/4*3/4 + 1/4*3^2/4^2 + 3/4*3^3/4^3 + 1/4*3^3/4^3 + ...
|
||||
;
|
||||
; Simplify by splitting up the odd and even terms of the series and taking out
|
||||
; factors so that the infite series matches:
|
||||
;
|
||||
; c1 = 3/4 *(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
|
||||
; + 3/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
|
||||
; c2 = 1/4 *(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
|
||||
; + 9/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
|
||||
;
|
||||
; c1 = 15/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
|
||||
; c2 = 13/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
|
||||
;
|
||||
; Since this geometric series sums to 16/7:
|
||||
;
|
||||
; c1 = 15/7
|
||||
; c2 = 13/7
|
||||
;
|
||||
; If we treat c1 and c2 as members of the same loop, the exit frequency of the
|
||||
; loop as a whole is 1/4, so the loop scale should be 4. Summing c1 and c2
|
||||
; gives 28/7, or 4.0, which is nice confirmation of the math above.
|
||||
;
|
||||
; However, assuming c1 precedes c2 in reverse post-order, the current algorithm
|
||||
; returns 3/4 and 13/16, respectively. LoopInfo ignores edges between loops
|
||||
; (and doesn't see any loops here at all), and -block-freq ignores the
|
||||
; irreducible edge from c2 to c1.
|
||||
;
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'multientry':
|
||||
; CHECK-NEXT: block-frequency-info: multientry
|
||||
define void @multientry(i32 %a) {
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
%choose = call i32 @choose(i32 %a)
|
||||
%compare = icmp ugt i32 %choose, %a
|
||||
br i1 %compare, label %c1, label %c2, !prof !2
|
||||
|
||||
; This is like a single-line XFAIL (see above).
|
||||
; CHECK-NEXT: c1:
|
||||
; CHECK-NOT: float = 2.142857{{[0-9]*}},
|
||||
c1:
|
||||
%i1 = phi i32 [ %a, %entry ], [ %i2.inc, %c2 ]
|
||||
%i1.inc = add i32 %i1, 1
|
||||
%choose1 = call i32 @choose(i32 %i1)
|
||||
%compare1 = icmp ugt i32 %choose1, %a
|
||||
br i1 %compare1, label %c2, label %exit, !prof !2
|
||||
|
||||
; This is like a single-line XFAIL (see above).
|
||||
; CHECK-NEXT: c2:
|
||||
; CHECK-NOT: float = 1.857142{{[0-9]*}},
|
||||
c2:
|
||||
%i2 = phi i32 [ %a, %entry ], [ %i1.inc, %c1 ]
|
||||
%i2.inc = add i32 %i2, 1
|
||||
%choose2 = call i32 @choose(i32 %i2)
|
||||
%compare2 = icmp ugt i32 %choose2, %a
|
||||
br i1 %compare2, label %c1, label %exit, !prof !2
|
||||
|
||||
; We still shouldn't lose any frequency.
|
||||
; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
|
||||
exit:
|
||||
ret void
|
||||
}
|
||||
|
||||
; Testcase #2
|
||||
; ===========
|
||||
;
|
||||
; In this case c1 and c2 should be treated as equals in a single loop. The
|
||||
; exit frequency is 1/3, so the scaling factor for the loop should be 3.0. The
|
||||
; loop is entered 2/3 of the time, and c1 and c2 split the total loop frequency
|
||||
; evenly (1/2), so they should each have frequencies of 1.0 (3.0*2/3*1/2).
|
||||
; Another way of computing this result is by assigning 1.0 to entry and showing
|
||||
; that c1 and c2 should accumulate frequencies of:
|
||||
;
|
||||
; 1/3 + 2/9 + 4/27 + 8/81 + ...
|
||||
; 2^0/3^1 + 2^1/3^2 + 2^2/3^3 + 2^3/3^4 + ...
|
||||
;
|
||||
; At the first step, c1 and c2 each get 1/3 of the entry. At each subsequent
|
||||
; step, c1 and c2 each get 1/3 of what's left in c1 and c2 combined. This
|
||||
; infinite series sums to 1.
|
||||
;
|
||||
; However, assuming c1 precedes c2 in reverse post-order, the current algorithm
|
||||
; returns 1/2 and 3/4, respectively. LoopInfo ignores edges between loops (and
|
||||
; treats c1 and c2 as self-loops only), and -block-freq ignores the irreducible
|
||||
; edge from c2 to c1.
|
||||
;
|
||||
; Below I use a CHECK-NEXT/NOT combo like an XFAIL with the granularity of a
|
||||
; single check. If/when this behaviour is fixed, we'll know about it, and the
|
||||
; test should be updated.
|
||||
;
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'crossloops':
|
||||
; CHECK-NEXT: block-frequency-info: crossloops
|
||||
define void @crossloops(i32 %a) {
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
%choose = call i32 @choose(i32 %a)
|
||||
switch i32 %choose, label %exit [ i32 1, label %c1
|
||||
i32 2, label %c2 ], !prof !3
|
||||
|
||||
; This is like a single-line XFAIL (see above).
|
||||
; CHECK-NEXT: c1:
|
||||
; CHECK-NOT: float = 1.0,
|
||||
c1:
|
||||
%i1 = phi i32 [ %a, %entry ], [ %i1.inc, %c1 ], [ %i2.inc, %c2 ]
|
||||
%i1.inc = add i32 %i1, 1
|
||||
%choose1 = call i32 @choose(i32 %i1)
|
||||
switch i32 %choose1, label %exit [ i32 1, label %c1
|
||||
i32 2, label %c2 ], !prof !3
|
||||
|
||||
; This is like a single-line XFAIL (see above).
|
||||
; CHECK-NEXT: c2:
|
||||
; CHECK-NOT: float = 1.0,
|
||||
c2:
|
||||
%i2 = phi i32 [ %a, %entry ], [ %i1.inc, %c1 ], [ %i2.inc, %c2 ]
|
||||
%i2.inc = add i32 %i2, 1
|
||||
%choose2 = call i32 @choose(i32 %i2)
|
||||
switch i32 %choose2, label %exit [ i32 1, label %c1
|
||||
i32 2, label %c2 ], !prof !3
|
||||
|
||||
; We still shouldn't lose any frequency.
|
||||
; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
|
||||
exit:
|
||||
ret void
|
||||
}
|
||||
|
||||
declare i32 @choose(i32)
|
||||
|
||||
!2 = metadata !{metadata !"branch_weights", i32 3, i32 1}
|
||||
!3 = metadata !{metadata !"branch_weights", i32 2, i32 2, i32 2}
|
||||
44
test/Analysis/BlockFrequencyInfo/loop_with_branch.ll
Normal file
44
test/Analysis/BlockFrequencyInfo/loop_with_branch.ll
Normal file
@@ -0,0 +1,44 @@
|
||||
; RUN: opt < %s -analyze -block-freq | FileCheck %s
|
||||
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'loop_with_branch':
|
||||
; CHECK-NEXT: block-frequency-info: loop_with_branch
|
||||
define void @loop_with_branch(i32 %a) {
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
%skip_loop = call i1 @foo0(i32 %a)
|
||||
br i1 %skip_loop, label %skip, label %header, !prof !0
|
||||
|
||||
; CHECK-NEXT: skip: float = 0.25,
|
||||
skip:
|
||||
br label %exit
|
||||
|
||||
; CHECK-NEXT: header: float = 4.5,
|
||||
header:
|
||||
%i = phi i32 [ 0, %entry ], [ %i.next, %back ]
|
||||
%i.next = add i32 %i, 1
|
||||
%choose = call i2 @foo1(i32 %i)
|
||||
switch i2 %choose, label %exit [ i2 0, label %left
|
||||
i2 1, label %right ], !prof !1
|
||||
|
||||
; CHECK-NEXT: left: float = 1.5,
|
||||
left:
|
||||
br label %back
|
||||
|
||||
; CHECK-NEXT: right: float = 2.25,
|
||||
right:
|
||||
br label %back
|
||||
|
||||
; CHECK-NEXT: back: float = 3.75,
|
||||
back:
|
||||
br label %header
|
||||
|
||||
; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
|
||||
exit:
|
||||
ret void
|
||||
}
|
||||
|
||||
declare i1 @foo0(i32)
|
||||
declare i2 @foo1(i32)
|
||||
|
||||
!0 = metadata !{metadata !"branch_weights", i32 1, i32 3}
|
||||
!1 = metadata !{metadata !"branch_weights", i32 1, i32 2, i32 3}
|
||||
@@ -0,0 +1,59 @@
|
||||
; RUN: opt < %s -analyze -block-freq | FileCheck %s
|
||||
|
||||
; CHECK-LABEL: Printing analysis {{.*}} for function 'nested_loop_with_branches'
|
||||
; CHECK-NEXT: block-frequency-info: nested_loop_with_branches
|
||||
define void @nested_loop_with_branches(i32 %a) {
|
||||
; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
|
||||
entry:
|
||||
%v0 = call i1 @foo0(i32 %a)
|
||||
br i1 %v0, label %exit, label %outer, !prof !0
|
||||
|
||||
; CHECK-NEXT: outer: float = 12.0,
|
||||
outer:
|
||||
%i = phi i32 [ 0, %entry ], [ %i.next, %inner.end ], [ %i.next, %no_inner ]
|
||||
%i.next = add i32 %i, 1
|
||||
%do_inner = call i1 @foo1(i32 %i)
|
||||
br i1 %do_inner, label %no_inner, label %inner, !prof !0
|
||||
|
||||
; CHECK-NEXT: inner: float = 36.0,
|
||||
inner:
|
||||
%j = phi i32 [ 0, %outer ], [ %j.next, %inner.end ]
|
||||
%side = call i1 @foo3(i32 %j)
|
||||
br i1 %side, label %left, label %right, !prof !0
|
||||
|
||||
; CHECK-NEXT: left: float = 9.0,
|
||||
left:
|
||||
%v4 = call i1 @foo4(i32 %j)
|
||||
br label %inner.end
|
||||
|
||||
; CHECK-NEXT: right: float = 27.0,
|
||||
right:
|
||||
%v5 = call i1 @foo5(i32 %j)
|
||||
br label %inner.end
|
||||
|
||||
; CHECK-NEXT: inner.end: float = 36.0,
|
||||
inner.end:
|
||||
%stay_inner = phi i1 [ %v4, %left ], [ %v5, %right ]
|
||||
%j.next = add i32 %j, 1
|
||||
br i1 %stay_inner, label %inner, label %outer, !prof !1
|
||||
|
||||
; CHECK-NEXT: no_inner: float = 3.0,
|
||||
no_inner:
|
||||
%continue = call i1 @foo6(i32 %i)
|
||||
br i1 %continue, label %outer, label %exit, !prof !1
|
||||
|
||||
; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
|
||||
exit:
|
||||
ret void
|
||||
}
|
||||
|
||||
declare i1 @foo0(i32)
|
||||
declare i1 @foo1(i32)
|
||||
declare i1 @foo2(i32)
|
||||
declare i1 @foo3(i32)
|
||||
declare i1 @foo4(i32)
|
||||
declare i1 @foo5(i32)
|
||||
declare i1 @foo6(i32)
|
||||
|
||||
!0 = metadata !{metadata !"branch_weights", i32 1, i32 3}
|
||||
!1 = metadata !{metadata !"branch_weights", i32 3, i32 1}
|
||||
@@ -287,9 +287,8 @@ define void @Unwind1() {
|
||||
; CHECKFP: .LBB{{[0-9_]+}}
|
||||
; CHECKFP-NEXT: ldc r2, 40
|
||||
; CHECKFP-NEXT: add r2, r10, r2
|
||||
; CHECKFP-NEXT: add r0, r2, r0
|
||||
; CHECKFP-NEXT: add r2, r2, r0
|
||||
; CHECKFP-NEXT: mov r3, r1
|
||||
; CHECKFP-NEXT: mov r2, r0
|
||||
; CHECKFP-NEXT: ldw r9, r10[4]
|
||||
; CHECKFP-NEXT: ldw r8, r10[5]
|
||||
; CHECKFP-NEXT: ldw r7, r10[6]
|
||||
@@ -337,9 +336,8 @@ define void @Unwind1() {
|
||||
; CHECK-NEXT: ldc r2, 36
|
||||
; CHECK-NEXT: ldaw r3, sp[0]
|
||||
; CHECK-NEXT: add r2, r3, r2
|
||||
; CHECK-NEXT: add r0, r2, r0
|
||||
; CHECK-NEXT: add r2, r2, r0
|
||||
; CHECK-NEXT: mov r3, r1
|
||||
; CHECK-NEXT: mov r2, r0
|
||||
; CHECK-NEXT: ldw r10, sp[2]
|
||||
; CHECK-NEXT: ldw r9, sp[3]
|
||||
; CHECK-NEXT: ldw r8, sp[4]
|
||||
|
||||
Reference in New Issue
Block a user