#ifndef LLVM_IR_PREDITERATORCACHE_H
#define LLVM_IR_PREDITERATORCACHE_H
+#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/IR/CFG.h"
namespace llvm {
- /// PredIteratorCache - This class is an extremely trivial cache for
- /// predecessor iterator queries. This is useful for code that repeatedly
- /// wants the predecessor list for the same blocks.
- class PredIteratorCache {
- /// BlockToPredsMap - Pointer to null-terminated list.
- DenseMap<BasicBlock*, BasicBlock**> BlockToPredsMap;
- DenseMap<BasicBlock*, unsigned> BlockToPredCountMap;
+/// PredIteratorCache - This class is an extremely trivial cache for
+/// predecessor iterator queries. This is useful for code that repeatedly
+/// wants the predecessor list for the same blocks.
+class PredIteratorCache {
+ /// BlockToPredsMap - Pointer to null-terminated list.
+ DenseMap<BasicBlock *, BasicBlock **> BlockToPredsMap;
+ DenseMap<BasicBlock *, unsigned> BlockToPredCountMap;
- /// Memory - This is the space that holds cached preds.
- BumpPtrAllocator Memory;
- public:
+ /// Memory - This is the space that holds cached preds.
+ BumpPtrAllocator Memory;
- /// GetPreds - Get a cached list for the null-terminated predecessor list of
- /// the specified block. This can be used in a loop like this:
- /// for (BasicBlock **PI = PredCache->GetPreds(BB); *PI; ++PI)
- /// use(*PI);
- /// instead of:
- /// for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
- BasicBlock **GetPreds(BasicBlock *BB) {
- BasicBlock **&Entry = BlockToPredsMap[BB];
- if (Entry) return Entry;
+private:
+ /// GetPreds - Get a cached list for the null-terminated predecessor list of
+ /// the specified block. This can be used in a loop like this:
+ /// for (BasicBlock **PI = PredCache->GetPreds(BB); *PI; ++PI)
+ /// use(*PI);
+ /// instead of:
+ /// for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
+ BasicBlock **GetPreds(BasicBlock *BB) {
+ BasicBlock **&Entry = BlockToPredsMap[BB];
+ if (Entry)
+ return Entry;
- SmallVector<BasicBlock*, 32> PredCache(pred_begin(BB), pred_end(BB));
- PredCache.push_back(nullptr); // null terminator.
-
- BlockToPredCountMap[BB] = PredCache.size()-1;
+ SmallVector<BasicBlock *, 32> PredCache(pred_begin(BB), pred_end(BB));
+ PredCache.push_back(nullptr); // null terminator.
- Entry = Memory.Allocate<BasicBlock*>(PredCache.size());
- std::copy(PredCache.begin(), PredCache.end(), Entry);
- return Entry;
- }
-
- unsigned GetNumPreds(BasicBlock *BB) {
- GetPreds(BB);
- return BlockToPredCountMap[BB];
- }
+ BlockToPredCountMap[BB] = PredCache.size() - 1;
+
+ Entry = Memory.Allocate<BasicBlock *>(PredCache.size());
+ std::copy(PredCache.begin(), PredCache.end(), Entry);
+ return Entry;
+ }
+
+ unsigned GetNumPreds(BasicBlock *BB) {
+ GetPreds(BB);
+ return BlockToPredCountMap[BB];
+ }
+
+public:
+ size_t size(BasicBlock *BB) { return GetNumPreds(BB); }
+ ArrayRef<BasicBlock *> get(BasicBlock *BB) {
+ return makeArrayRef(GetPreds(BB), GetNumPreds(BB));
+ }
+
+ /// clear - Remove all information.
+ void clear() {
+ BlockToPredsMap.clear();
+ BlockToPredCountMap.clear();
+ Memory.Reset();
+ }
+};
- /// clear - Remove all information.
- void clear() {
- BlockToPredsMap.clear();
- BlockToPredCountMap.clear();
- Memory.Reset();
- }
- };
} // end namespace llvm
#endif