intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 142 insertions, 0 deletions

diff --git a/contrib/libs/llvm12/include/llvm/CodeGen/GlobalISel/GISelKnownBits.h b/contrib/libs/llvm12/include/llvm/CodeGen/GlobalISel/GISelKnownBits.h
new file mode 100644
index 0000000000..452ddd17c0
--- /dev/null
+++ b/contrib/libs/llvm12/include/llvm/CodeGen/GlobalISel/GISelKnownBits.h
@@ -0,0 +1,142 @@
+#pragma once
+
+#ifdef __GNUC__
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-parameter"
+#endif
+
+//===- llvm/CodeGen/GlobalISel/GISelKnownBits.h ---------------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+/// Provides analysis for querying information about KnownBits during GISel
+/// passes.
+//
+//===----------------------------------------------------------------------===//
+#ifndef LLVM_CODEGEN_GLOBALISEL_KNOWNBITSINFO_H
+#define LLVM_CODEGEN_GLOBALISEL_KNOWNBITSINFO_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/CodeGen/GlobalISel/GISelChangeObserver.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/Register.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Support/KnownBits.h"
+
+namespace llvm {
+
+class TargetLowering;
+class DataLayout;
+
+class GISelKnownBits : public GISelChangeObserver {
+  MachineFunction &MF;
+  MachineRegisterInfo &MRI;
+  const TargetLowering &TL;
+  const DataLayout &DL;
+  unsigned MaxDepth;
+  /// Cache maintained during a computeKnownBits request.
+  SmallDenseMap<Register, KnownBits, 16> ComputeKnownBitsCache;
+
+  void computeKnownBitsMin(Register Src0, Register Src1, KnownBits &Known,
+                           const APInt &DemandedElts,
+                           unsigned Depth = 0);
+
+  unsigned computeNumSignBitsMin(Register Src0, Register Src1,
+                                 const APInt &DemandedElts, unsigned Depth = 0);
+
+public:
+  GISelKnownBits(MachineFunction &MF, unsigned MaxDepth = 6);
+  virtual ~GISelKnownBits() = default;
+
+  const MachineFunction &getMachineFunction() const {
+    return MF;
+  }
+
+  const DataLayout &getDataLayout() const {
+    return DL;
+  }
+
+  virtual void computeKnownBitsImpl(Register R, KnownBits &Known,
+                                    const APInt &DemandedElts,
+                                    unsigned Depth = 0);
+
+  unsigned computeNumSignBits(Register R, const APInt &DemandedElts,
+                              unsigned Depth = 0);
+  unsigned computeNumSignBits(Register R, unsigned Depth = 0);
+
+  // KnownBitsAPI
+  KnownBits getKnownBits(Register R);
+  KnownBits getKnownBits(Register R, const APInt &DemandedElts,
+                         unsigned Depth = 0);
+
+  // Calls getKnownBits for first operand def of MI.
+  KnownBits getKnownBits(MachineInstr &MI);
+  APInt getKnownZeroes(Register R);
+  APInt getKnownOnes(Register R);
+
+  /// \return true if 'V & Mask' is known to be zero in DemandedElts. We use
+  /// this predicate to simplify operations downstream.
+  /// Mask is known to be zero for bits that V cannot have.
+  bool maskedValueIsZero(Register Val, const APInt &Mask) {
+    return Mask.isSubsetOf(getKnownBits(Val).Zero);
+  }
+
+  /// \return true if the sign bit of Op is known to be zero.  We use this
+  /// predicate to simplify operations downstream.
+  bool signBitIsZero(Register Op);
+
+  static void computeKnownBitsForAlignment(KnownBits &Known,
+                                           Align Alignment) {
+    // The low bits are known zero if the pointer is aligned.
+    Known.Zero.setLowBits(Log2(Alignment));
+  }
+
+  /// \return The known alignment for the pointer-like value \p R.
+  Align computeKnownAlignment(Register R, unsigned Depth = 0);
+
+  // Observer API. No-op for non-caching implementation.
+  void erasingInstr(MachineInstr &MI) override{};
+  void createdInstr(MachineInstr &MI) override{};
+  void changingInstr(MachineInstr &MI) override{};
+  void changedInstr(MachineInstr &MI) override{};
+
+protected:
+  unsigned getMaxDepth() const { return MaxDepth; }
+};
+
+/// To use KnownBitsInfo analysis in a pass,
+/// KnownBitsInfo &Info = getAnalysis<GISelKnownBitsInfoAnalysis>().get(MF);
+/// Add to observer if the Info is caching.
+/// WrapperObserver.addObserver(Info);
+
+/// Eventually add other features such as caching/ser/deserializing
+/// to MIR etc. Those implementations can derive from GISelKnownBits
+/// and override computeKnownBitsImpl.
+class GISelKnownBitsAnalysis : public MachineFunctionPass {
+  std::unique_ptr<GISelKnownBits> Info;
+
+public:
+  static char ID;
+  GISelKnownBitsAnalysis() : MachineFunctionPass(ID) {
+    initializeGISelKnownBitsAnalysisPass(*PassRegistry::getPassRegistry());
+  }
+  GISelKnownBits &get(MachineFunction &MF) {
+    if (!Info)
+      Info = std::make_unique<GISelKnownBits>(MF);
+    return *Info.get();
+  }
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+  bool runOnMachineFunction(MachineFunction &MF) override;
+  void releaseMemory() override { Info.reset(); }
+};
+} // namespace llvm
+
+#endif // ifdef
+
+#ifdef __GNUC__
+#pragma GCC diagnostic pop
+#endif