Speculative Compilation
[ORC] Remove Speculator Variants for Different Program Representations
[ORC] Block Freq Analysis
Speculative Compilation with Naive Block Frequency
Add Applications to OrcSpeculation
ORC v2 with Block Freq Query & Example
Deleted BenchMark Programs
Signed-off-by: preejackie <praveenvelliengiri@gmail.com>
ORCv2 comments resolved
[ORCV2] NFC
ORCv2 NFC
[ORCv2] Speculative compilation - CFGWalkQuery
ORCv2 Adapting IRSpeculationLayer to new locking scheme
llvm-svn: 367756
diff --git a/llvm/lib/ExecutionEngine/Orc/SpeculateAnalyses.cpp b/llvm/lib/ExecutionEngine/Orc/SpeculateAnalyses.cpp
new file mode 100644
index 0000000..9d8c2f3
--- /dev/null
+++ b/llvm/lib/ExecutionEngine/Orc/SpeculateAnalyses.cpp
@@ -0,0 +1,87 @@
+//===-- SpeculateAnalyses.cpp --*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ExecutionEngine/Orc/SpeculateAnalyses.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Analysis/BlockFrequencyInfo.h"
+
+// Implementations of Queries shouldn't need to lock the resources
+// such as LLVMContext, each argument (function) has a non-shared LLVMContext
+namespace llvm {
+namespace orc {
+
+// Collect direct calls only
+void BlockFreqQuery::findCalles(const BasicBlock *BB,
+ DenseSet<StringRef> &CallesNames) {
+ assert(BB != nullptr && "Traversing Null BB to find calls?");
+
+ auto getCalledFunction = [&CallesNames](const CallBase *Call) {
+ auto CalledValue = Call->getCalledOperand()->stripPointerCasts();
+ if (auto DirectCall = dyn_cast<Function>(CalledValue))
+ CallesNames.insert(DirectCall->getName());
+ };
+ for (auto &I : BB->instructionsWithoutDebug())
+ if (auto CI = dyn_cast<CallInst>(&I))
+ getCalledFunction(CI);
+
+ if (auto II = dyn_cast<InvokeInst>(BB->getTerminator()))
+ getCalledFunction(II);
+}
+
+// blind calculation
+size_t BlockFreqQuery::numBBToGet(size_t numBB) {
+ // small CFG
+ if (numBB < 4)
+ return numBB;
+ // mid-size CFG
+ else if (numBB < 20)
+ return (numBB / 2);
+ else
+ return (numBB / 2) + (numBB / 4);
+}
+
+BlockFreqQuery::ResultTy BlockFreqQuery::
+operator()(Function &F, FunctionAnalysisManager &FAM) {
+ DenseMap<StringRef, DenseSet<StringRef>> CallerAndCalles;
+ DenseSet<StringRef> Calles;
+ SmallVector<std::pair<const BasicBlock *, uint64_t>, 8> BBFreqs;
+
+ auto IBBs = findBBwithCalls(F);
+
+ if (IBBs.empty())
+ return None;
+
+ auto &BFI = FAM.getResult<BlockFrequencyAnalysis>(F);
+
+ for (const auto I : IBBs)
+ BBFreqs.push_back({I, BFI.getBlockFreq(I).getFrequency()});
+
+ assert(IBBs.size() == BBFreqs.size() && "BB Count Mismatch");
+
+ llvm::sort(BBFreqs.begin(), BBFreqs.end(),
+ [](decltype(BBFreqs)::const_reference BBF,
+ decltype(BBFreqs)::const_reference BBS) {
+ return BBF.second > BBS.second ? true : false;
+ });
+
+ // ignoring number of direct calls in a BB
+ auto Topk = numBBToGet(BBFreqs.size());
+
+ for (size_t i = 0; i < Topk; i++)
+ findCalles(BBFreqs[i].first, Calles);
+
+ assert(!Calles.empty() && "Running Analysis on Function with no calls?");
+
+ CallerAndCalles.insert({F.getName(), std::move(Calles)});
+
+ return CallerAndCalles;
+}
+} // namespace orc
+} // namespace llvm