Imported Upstream version 5.18.0.167

Former-commit-id: 289509151e0fee68a1b591a20c9f109c3c789d3a

external/llvm/lib/CodeGen/SelectionDAG/StatepointLowering.h

@@ -1,124 +0,0 @@
-//===- StatepointLowering.h - SDAGBuilder's statepoint code ---*- C++ -*---===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file includes support code use by SelectionDAGBuilder when lowering a
-// statepoint sequence in SelectionDAG IR.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_LIB_CODEGEN_SELECTIONDAG_STATEPOINTLOWERING_H
-#define LLVM_LIB_CODEGEN_SELECTIONDAG_STATEPOINTLOWERING_H
-
-#include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/SmallBitVector.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/CodeGen/SelectionDAGNodes.h"
-#include "llvm/CodeGen/ValueTypes.h"
-#include <cassert>
-
-namespace llvm {
-
-class CallInst;
-class SelectionDAGBuilder;
-
-/// This class tracks both per-statepoint and per-selectiondag information.
-/// For each statepoint it tracks locations of it's gc valuess (incoming and
-/// relocated) and list of gcreloc calls scheduled for visiting (this is
-/// used for a debug mode consistency check only).  The spill slot tracking
-/// works in concert with information in FunctionLoweringInfo.
-class StatepointLoweringState {
-public:
-  StatepointLoweringState() = default;
-
-  /// Reset all state tracking for a newly encountered safepoint.  Also
-  /// performs some consistency checking.
-  void startNewStatepoint(SelectionDAGBuilder &Builder);
-
-  /// Clear the memory usage of this object.  This is called from
-  /// SelectionDAGBuilder::clear.  We require this is never called in the
-  /// midst of processing a statepoint sequence.
-  void clear();
-
-  /// Returns the spill location of a value incoming to the current
-  /// statepoint.  Will return SDValue() if this value hasn't been
-  /// spilled.  Otherwise, the value has already been spilled and no
-  /// further action is required by the caller.
-  SDValue getLocation(SDValue Val) {
-    auto I = Locations.find(Val);
-    if (I == Locations.end())
-      return SDValue();
-    return I->second;
-  }
-
-  void setLocation(SDValue Val, SDValue Location) {
-    assert(!Locations.count(Val) &&
-           "Trying to allocate already allocated location");
-    Locations[Val] = Location;
-  }
-
-  /// Record the fact that we expect to encounter a given gc_relocate
-  /// before the next statepoint.  If we don't see it, we'll report
-  /// an assertion.
-  void scheduleRelocCall(const CallInst &RelocCall) {
-    PendingGCRelocateCalls.push_back(&RelocCall);
-  }
-
-  /// Remove this gc_relocate from the list we're expecting to see
-  /// before the next statepoint.  If we weren't expecting to see
-  /// it, we'll report an assertion.
-  void relocCallVisited(const CallInst &RelocCall) {
-    auto I = llvm::find(PendingGCRelocateCalls, &RelocCall);
-    assert(I != PendingGCRelocateCalls.end() &&
-           "Visited unexpected gcrelocate call");
-    PendingGCRelocateCalls.erase(I);
-  }
-
-  // TODO: Should add consistency tracking to ensure we encounter
-  // expected gc_result calls too.
-
-  /// Get a stack slot we can use to store an value of type ValueType.  This
-  /// will hopefully be a recylced slot from another statepoint.
-  SDValue allocateStackSlot(EVT ValueType, SelectionDAGBuilder &Builder);
-
-  void reserveStackSlot(int Offset) {
-    assert(Offset >= 0 && Offset < (int)AllocatedStackSlots.size() &&
-           "out of bounds");
-    assert(!AllocatedStackSlots.test(Offset) && "already reserved!");
-    assert(NextSlotToAllocate <= (unsigned)Offset && "consistency!");
-    AllocatedStackSlots.set(Offset);
-  }
-
-  bool isStackSlotAllocated(int Offset) {
-    assert(Offset >= 0 && Offset < (int)AllocatedStackSlots.size() &&
-           "out of bounds");
-    return AllocatedStackSlots.test(Offset);
-  }
-
-private:
-  /// Maps pre-relocation value (gc pointer directly incoming into statepoint)
-  /// into it's location (currently only stack slots)
-  DenseMap<SDValue, SDValue> Locations;
-
-  /// A boolean indicator for each slot listed in the FunctionInfo as to
-  /// whether it has been used in the current statepoint.  Since we try to
-  /// preserve stack slots across safepoints, there can be gaps in which
-  /// slots have been allocated.
-  SmallBitVector AllocatedStackSlots;
-
-  /// Points just beyond the last slot known to have been allocated
-  unsigned NextSlotToAllocate = 0;
-
-  /// Keep track of pending gcrelocate calls for consistency check
-  SmallVector<const CallInst *, 10> PendingGCRelocateCalls;
-};
-
-} // end namespace llvm
-
-#endif // LLVM_LIB_CODEGEN_SELECTIONDAG_STATEPOINTLOWERING_H