Merge "Update prebuilt Clang to r353983." into p9.0HEADp9.0-backupp9.0

1 files changed, 161 insertions, 0 deletions

diff --git a/clang-r353983/include/llvm/DebugInfo/MSF/MSFCommon.h b/clang-r353983/include/llvm/DebugInfo/MSF/MSFCommon.h
new file mode 100644
index 00000000..83331b14
--- /dev/null
+++ b/clang-r353983/include/llvm/DebugInfo/MSF/MSFCommon.h
@@ -0,0 +1,161 @@
+//===- MSFCommon.h - Common types and functions for MSF files ---*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_DEBUGINFO_MSF_MSFCOMMON_H
+#define LLVM_DEBUGINFO_MSF_MSFCOMMON_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/BitVector.h"
+#include "llvm/Support/Endian.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/MathExtras.h"
+#include <cstdint>
+#include <vector>
+
+namespace llvm {
+namespace msf {
+
+static const char Magic[] = {'M',  'i',  'c',    'r', 'o', 's',  'o',  'f',
+                             't',  ' ',  'C',    '/', 'C', '+',  '+',  ' ',
+                             'M',  'S',  'F',    ' ', '7', '.',  '0',  '0',
+                             '\r', '\n', '\x1a', 'D', 'S', '\0', '\0', '\0'};
+
+// The superblock is overlaid at the beginning of the file (offset 0).
+// It starts with a magic header and is followed by information which
+// describes the layout of the file system.
+struct SuperBlock {
+  char MagicBytes[sizeof(Magic)];
+  // The file system is split into a variable number of fixed size elements.
+  // These elements are referred to as blocks.  The size of a block may vary
+  // from system to system.
+  support::ulittle32_t BlockSize;
+  // The index of the free block map.
+  support::ulittle32_t FreeBlockMapBlock;
+  // This contains the number of blocks resident in the file system.  In
+  // practice, NumBlocks * BlockSize is equivalent to the size of the MSF
+  // file.
+  support::ulittle32_t NumBlocks;
+  // This contains the number of bytes which make up the directory.
+  support::ulittle32_t NumDirectoryBytes;
+  // This field's purpose is not yet known.
+  support::ulittle32_t Unknown1;
+  // This contains the block # of the block map.
+  support::ulittle32_t BlockMapAddr;
+};
+
+struct MSFLayout {
+  MSFLayout() = default;
+
+  uint32_t mainFpmBlock() const {
+    assert(SB->FreeBlockMapBlock == 1 || SB->FreeBlockMapBlock == 2);
+    return SB->FreeBlockMapBlock;
+  }
+
+  uint32_t alternateFpmBlock() const {
+    // If mainFpmBlock is 1, this is 2.  If mainFpmBlock is 2, this is 1.
+    return 3U - mainFpmBlock();
+  }
+
+  const SuperBlock *SB = nullptr;
+  BitVector FreePageMap;
+  ArrayRef<support::ulittle32_t> DirectoryBlocks;
+  ArrayRef<support::ulittle32_t> StreamSizes;
+  std::vector<ArrayRef<support::ulittle32_t>> StreamMap;
+};
+
+/// Describes the layout of a stream in an MSF layout.  A "stream" here
+/// is defined as any logical unit of data which may be arranged inside the MSF
+/// file as a sequence of (possibly discontiguous) blocks.  When we want to read
+/// from a particular MSF Stream, we fill out a stream layout structure and the
+/// reader uses it to determine which blocks in the underlying MSF file contain
+/// the data, so that it can be pieced together in the right order.
+class MSFStreamLayout {
+public:
+  uint32_t Length;
+  std::vector<support::ulittle32_t> Blocks;
+};
+
+/// Determine the layout of the FPM stream, given the MSF layout.  An FPM
+/// stream spans 1 or more blocks, each at equally spaced intervals throughout
+/// the file.
+MSFStreamLayout getFpmStreamLayout(const MSFLayout &Msf,
+                                   bool IncludeUnusedFpmData = false,
+                                   bool AltFpm = false);
+
+inline bool isValidBlockSize(uint32_t Size) {
+  switch (Size) {
+  case 512:
+  case 1024:
+  case 2048:
+  case 4096:
+    return true;
+  }
+  return false;
+}
+
+// Super Block, Fpm0, Fpm1, and Block Map
+inline uint32_t getMinimumBlockCount() { return 4; }
+
+// Super Block, Fpm0, and Fpm1 are reserved.  The Block Map, although required
+// need not be at block 3.
+inline uint32_t getFirstUnreservedBlock() { return 3; }
+
+inline uint64_t bytesToBlocks(uint64_t NumBytes, uint64_t BlockSize) {
+  return divideCeil(NumBytes, BlockSize);
+}
+
+inline uint64_t blockToOffset(uint64_t BlockNumber, uint64_t BlockSize) {
+  return BlockNumber * BlockSize;
+}
+
+inline uint32_t getFpmIntervalLength(const MSFLayout &L) {
+  return L.SB->BlockSize;
+}
+
+/// Given an MSF with the specified block size and number of blocks, determine
+/// how many pieces the specified Fpm is split into.
+/// \p BlockSize - the block size of the MSF
+/// \p NumBlocks - the total number of blocks in the MSF
+/// \p IncludeUnusedFpmData - When true, this will count every block that is
+///    both in the file and matches the form of an FPM block, even if some of
+///    those FPM blocks are unused (a single FPM block can describe the
+///    allocation status of up to 32,767 blocks, although one appears only
+///    every 4,096 blocks).  So there are 8x as many blocks that match the
+///    form as there are blocks that are necessary to describe the allocation
+///    status of the file.  When this parameter is false, these extraneous
+///    trailing blocks are not counted.
+inline uint32_t getNumFpmIntervals(uint32_t BlockSize, uint32_t NumBlocks,
+                                   bool IncludeUnusedFpmData, int FpmNumber) {
+  assert(FpmNumber == 1 || FpmNumber == 2);
+  if (IncludeUnusedFpmData) {
+    // This calculation determines how many times a number of the form
+    // BlockSize * k + N appears in the range [0, NumBlocks).  We only need to
+    // do this when unused data is included, since the number of blocks dwarfs
+    // the number of fpm blocks.
+    return divideCeil(NumBlocks - FpmNumber, BlockSize);
+  }
+
+  // We want the minimum number of intervals required, where each interval can
+  // represent BlockSize * 8 blocks.
+  return divideCeil(NumBlocks, 8 * BlockSize);
+}
+
+inline uint32_t getNumFpmIntervals(const MSFLayout &L,
+                                   bool IncludeUnusedFpmData = false,
+                                   bool AltFpm = false) {
+  return getNumFpmIntervals(L.SB->BlockSize, L.SB->NumBlocks,
+                            IncludeUnusedFpmData,
+                            AltFpm ? L.alternateFpmBlock() : L.mainFpmBlock());
+}
+
+Error validateSuperBlock(const SuperBlock &SB);
+
+} // end namespace msf
+} // end namespace llvm
+
+#endif // LLVM_DEBUGINFO_MSF_MSFCOMMON_H