Move the on-disk hash table code into its own header. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@69580 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/PTHLexer.cpp b/lib/Lex/PTHLexer.cpp
index 923b26c..916bdef 100644
--- a/lib/Lex/PTHLexer.cpp
+++ b/lib/Lex/PTHLexer.cpp
@@ -14,6 +14,7 @@
#include "clang/Basic/TokenKinds.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/IdentifierTable.h"
+#include "clang/Basic/OnDiskHashTable.h"
#include "clang/Lex/PTHLexer.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Lex/PTHManager.h"
@@ -21,75 +22,14 @@
#include "clang/Lex/Preprocessor.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/OwningPtr.h"
-#include "llvm/Support/Compiler.h"
-#include "llvm/Support/MathExtras.h"
#include "llvm/Support/MemoryBuffer.h"
-#include "llvm/System/Host.h"
#include <sys/stat.h>
using namespace clang;
+using namespace clang::io;
#define DISK_TOKEN_SIZE (1+1+2+4+4)
//===----------------------------------------------------------------------===//
-// Utility methods for reading from the mmap'ed PTH file.
-//===----------------------------------------------------------------------===//
-
-static inline uint16_t ReadUnalignedLE16(const unsigned char *&Data) {
- uint16_t V = ((uint16_t)Data[0]) |
- ((uint16_t)Data[1] << 8);
- Data += 2;
- return V;
-}
-
-static inline uint32_t ReadUnalignedLE32(const unsigned char *&Data) {
- uint32_t V = ((uint32_t)Data[0]) |
- ((uint32_t)Data[1] << 8) |
- ((uint32_t)Data[2] << 16) |
- ((uint32_t)Data[3] << 24);
- Data += 4;
- return V;
-}
-
-static inline uint64_t ReadUnalignedLE64(const unsigned char *&Data) {
- uint64_t V = ((uint64_t)Data[0]) |
- ((uint64_t)Data[1] << 8) |
- ((uint64_t)Data[2] << 16) |
- ((uint64_t)Data[3] << 24) |
- ((uint64_t)Data[4] << 32) |
- ((uint64_t)Data[5] << 40) |
- ((uint64_t)Data[6] << 48) |
- ((uint64_t)Data[7] << 56);
- Data += 8;
- return V;
-}
-
-static inline uint32_t ReadLE32(const unsigned char *&Data) {
- // Hosts that directly support little-endian 32-bit loads can just
- // use them. Big-endian hosts need a bswap.
- uint32_t V = *((uint32_t*)Data);
- if (llvm::sys::isBigEndianHost())
- V = llvm::ByteSwap_32(V);
- Data += 4;
- return V;
-}
-
-// Bernstein hash function:
-// This is basically copy-and-paste from StringMap. This likely won't
-// stay here, which is why I didn't both to expose this function from
-// String Map.
-static unsigned BernsteinHash(const char* x) {
- unsigned int R = 0;
- for ( ; *x != '\0' ; ++x) R = R * 33 + *x;
- return R + (R >> 5);
-}
-
-static unsigned BernsteinHash(const char* x, unsigned n) {
- unsigned int R = 0;
- for (unsigned i = 0 ; i < n ; ++i, ++x) R = R * 33 + *x;
- return R + (R >> 5);
-}
-
-//===----------------------------------------------------------------------===//
// PTHLexer methods.
//===----------------------------------------------------------------------===//
@@ -344,115 +284,6 @@
}
//===----------------------------------------------------------------------===//
-// OnDiskChainedHashTable
-//===----------------------------------------------------------------------===//
-
-template<typename Info>
-class OnDiskChainedHashTable {
- const unsigned NumBuckets;
- const unsigned NumEntries;
- const unsigned char* const Buckets;
- const unsigned char* const Base;
-public:
- typedef typename Info::internal_key_type internal_key_type;
- typedef typename Info::external_key_type external_key_type;
- typedef typename Info::data_type data_type;
-
- OnDiskChainedHashTable(unsigned numBuckets, unsigned numEntries,
- const unsigned char* buckets,
- const unsigned char* base)
- : NumBuckets(numBuckets), NumEntries(numEntries),
- Buckets(buckets), Base(base) {
- assert((reinterpret_cast<uintptr_t>(buckets) & 0x3) == 0 &&
- "'buckets' must have a 4-byte alignment");
- }
-
- unsigned getNumBuckets() const { return NumBuckets; }
- unsigned getNumEntries() const { return NumEntries; }
- const unsigned char* getBase() const { return Base; }
- const unsigned char* getBuckets() const { return Buckets; }
-
- bool isEmpty() const { return NumEntries == 0; }
-
- class iterator {
- internal_key_type key;
- const unsigned char* const data;
- const unsigned len;
- public:
- iterator() : data(0), len(0) {}
- iterator(const internal_key_type k, const unsigned char* d, unsigned l)
- : key(k), data(d), len(l) {}
-
- data_type operator*() const { return Info::ReadData(key, data, len); }
- bool operator==(const iterator& X) const { return X.data == data; }
- bool operator!=(const iterator& X) const { return X.data != data; }
- };
-
- iterator find(const external_key_type& eKey) {
- const internal_key_type& iKey = Info::GetInternalKey(eKey);
- unsigned key_hash = Info::ComputeHash(iKey);
-
- // Each bucket is just a 32-bit offset into the PTH file.
- unsigned idx = key_hash & (NumBuckets - 1);
- const unsigned char* Bucket = Buckets + sizeof(uint32_t)*idx;
-
- unsigned offset = ReadLE32(Bucket);
- if (offset == 0) return iterator(); // Empty bucket.
- const unsigned char* Items = Base + offset;
-
- // 'Items' starts with a 16-bit unsigned integer representing the
- // number of items in this bucket.
- unsigned len = ReadUnalignedLE16(Items);
-
- for (unsigned i = 0; i < len; ++i) {
- // Read the hash.
- uint32_t item_hash = ReadUnalignedLE32(Items);
-
- // Determine the length of the key and the data.
- const std::pair<unsigned, unsigned>& L = Info::ReadKeyDataLength(Items);
- unsigned item_len = L.first + L.second;
-
- // Compare the hashes. If they are not the same, skip the entry entirely.
- if (item_hash != key_hash) {
- Items += item_len;
- continue;
- }
-
- // Read the key.
- const internal_key_type& X =
- Info::ReadKey((const unsigned char* const) Items, L.first);
-
- // If the key doesn't match just skip reading the value.
- if (!Info::EqualKey(X, iKey)) {
- Items += item_len;
- continue;
- }
-
- // The key matches!
- return iterator(X, Items + L.first, L.second);
- }
-
- return iterator();
- }
-
- iterator end() const { return iterator(); }
-
-
- static OnDiskChainedHashTable* Create(const unsigned char* buckets,
- const unsigned char* const base) {
-
- assert(buckets > base);
- assert((reinterpret_cast<uintptr_t>(buckets) & 0x3) == 0 &&
- "buckets should be 4-byte aligned.");
-
- unsigned numBuckets = ReadLE32(buckets);
- unsigned numEntries = ReadLE32(buckets);
- return new OnDiskChainedHashTable<Info>(numBuckets, numEntries, buckets,
- base);
- }
-};
-
-//===----------------------------------------------------------------------===//
// PTH file lookup: map from strings to file data.
//===----------------------------------------------------------------------===//