LLVM 20.0.0git
PredIteratorCache.h
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1//===- PredIteratorCache.h - pred_iterator Cache ----------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines the PredIteratorCache class.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_IR_PREDITERATORCACHE_H
14#define LLVM_IR_PREDITERATORCACHE_H
15
16#include "llvm/ADT/ArrayRef.h"
17#include "llvm/ADT/DenseMap.h"
19#include "llvm/IR/CFG.h"
21
22namespace llvm {
23
24/// PredIteratorCache - This class is an extremely trivial cache for
25/// predecessor iterator queries. This is useful for code that repeatedly
26/// wants the predecessor list for the same blocks.
28 /// Cached list of predecessors, allocated in Memory.
30
31 /// Memory - This is the space that holds cached preds.
33
34public:
35 size_t size(BasicBlock *BB) { return get(BB).size(); }
37 ArrayRef<BasicBlock *> &Entry = BlockToPredsMap[BB];
38 if (Entry.data())
39 return Entry;
40
42 BasicBlock **Data = Memory.Allocate<BasicBlock *>(PredCache.size());
43 std::copy(PredCache.begin(), PredCache.end(), Data);
44 Entry = ArrayRef(Data, PredCache.size());
45 return Entry;
46 }
47
48 /// clear - Remove all information.
49 void clear() {
50 BlockToPredsMap.clear();
51 Memory.Reset();
52 }
53};
54
55} // end namespace llvm
56
57#endif
This file defines the BumpPtrAllocator interface.
This file defines the DenseMap class.
This file provides various utilities for inspecting and working with the control flow graph in LLVM I...
This file defines the SmallVector class.
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: ArrayRef.h:41
LLVM Basic Block Representation.
Definition: BasicBlock.h:61
Allocate memory in an ever growing pool, as if by bump-pointer.
Definition: Allocator.h:66
PredIteratorCache - This class is an extremely trivial cache for predecessor iterator queries.
size_t size(BasicBlock *BB)
void clear()
clear - Remove all information.
ArrayRef< BasicBlock * > get(BasicBlock *BB)
size_t size() const
Definition: SmallVector.h:92
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.
Definition: SmallVector.h:1210
This class provides various memory handling functions that manipulate MemoryBlock instances.
Definition: Memory.h:52
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
auto predecessors(const MachineBasicBlock *BB)