Import prebuilt clang toolchain for linux.
diff --git a/linux-x64/clang/include/llvm/Analysis/DemandedBits.h b/linux-x64/clang/include/llvm/Analysis/DemandedBits.h
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+//===- llvm/Analysis/DemandedBits.h - Determine demanded bits ---*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass implements a demanded bits analysis. A demanded bit is one that
+// contributes to a result; bits that are not demanded can be either zero or
+// one without affecting control or data flow. For example in this sequence:
+//
+// %1 = add i32 %x, %y
+// %2 = trunc i32 %1 to i16
+//
+// Only the lowest 16 bits of %1 are demanded; the rest are removed by the
+// trunc.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_DEMANDED_BITS_H
+#define LLVM_ANALYSIS_DEMANDED_BITS_H
+
+#include "llvm/ADT/APInt.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/IR/PassManager.h"
+#include "llvm/Pass.h"
+
+namespace llvm {
+
+class AssumptionCache;
+class DominatorTree;
+class Function;
+class Instruction;
+struct KnownBits;
+class raw_ostream;
+
+class DemandedBits {
+public:
+ DemandedBits(Function &F, AssumptionCache &AC, DominatorTree &DT) :
+ F(F), AC(AC), DT(DT) {}
+
+ /// Return the bits demanded from instruction I.
+ APInt getDemandedBits(Instruction *I);
+
+ /// Return true if, during analysis, I could not be reached.
+ bool isInstructionDead(Instruction *I);
+
+ void print(raw_ostream &OS);
+
+private:
+ void performAnalysis();
+ void determineLiveOperandBits(const Instruction *UserI,
+ const Instruction *I, unsigned OperandNo,
+ const APInt &AOut, APInt &AB,
+ KnownBits &Known, KnownBits &Known2);
+
+ Function &F;
+ AssumptionCache ∾
+ DominatorTree &DT;
+
+ bool Analyzed = false;
+
+ // The set of visited instructions (non-integer-typed only).
+ SmallPtrSet<Instruction*, 32> Visited;
+ DenseMap<Instruction *, APInt> AliveBits;
+};
+
+class DemandedBitsWrapperPass : public FunctionPass {
+private:
+ mutable Optional<DemandedBits> DB;
+
+public:
+ static char ID; // Pass identification, replacement for typeid
+
+ DemandedBitsWrapperPass();
+
+ bool runOnFunction(Function &F) override;
+ void getAnalysisUsage(AnalysisUsage &AU) const override;
+
+ /// Clean up memory in between runs
+ void releaseMemory() override;
+
+ DemandedBits &getDemandedBits() { return *DB; }
+
+ void print(raw_ostream &OS, const Module *M) const override;
+};
+
+/// An analysis that produces \c DemandedBits for a function.
+class DemandedBitsAnalysis : public AnalysisInfoMixin<DemandedBitsAnalysis> {
+ friend AnalysisInfoMixin<DemandedBitsAnalysis>;
+
+ static AnalysisKey Key;
+
+public:
+ /// \brief Provide the result type for this analysis pass.
+ using Result = DemandedBits;
+
+ /// \brief Run the analysis pass over a function and produce demanded bits
+ /// information.
+ DemandedBits run(Function &F, FunctionAnalysisManager &AM);
+};
+
+/// \brief Printer pass for DemandedBits
+class DemandedBitsPrinterPass : public PassInfoMixin<DemandedBitsPrinterPass> {
+ raw_ostream &OS;
+
+public:
+ explicit DemandedBitsPrinterPass(raw_ostream &OS) : OS(OS) {}
+
+ PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
+};
+
+/// Create a demanded bits analysis pass.
+FunctionPass *createDemandedBitsWrapperPass();
+
+} // end namespace llvm
+
+#endif // LLVM_ANALYSIS_DEMANDED_BITS_H