yaml2obj: split out COFF logic into separate file

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183335 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 306 insertions, 0 deletions

diff --git a/tools/yaml2obj/yaml2coff.cpp b/tools/yaml2obj/yaml2coff.cpp
new file mode 100644
index 0000000000..54c5fb1256
--- /dev/null
+++ b/tools/yaml2obj/yaml2coff.cpp
@@ -0,0 +1,306 @@
+//===- yaml2coff - Convert YAML to a COFF object file ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief The COFF component of yaml2obj.
+///
+//===----------------------------------------------------------------------===//
+
+#include "yaml2obj.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/Object/COFFYAML.h"
+#include "llvm/Support/Endian.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/raw_ostream.h"
+#include <vector>
+
+using namespace llvm;
+
+/// This parses a yaml stream that represents a COFF object file.
+/// See docs/yaml2obj for the yaml scheema.
+struct COFFParser {
+  COFFParser(COFFYAML::Object &Obj) : Obj(Obj) {
+    // A COFF string table always starts with a 4 byte size field. Offsets into
+    // it include this size, so allocate it now.
+    StringTable.append(4, 0);
+  }
+
+  bool parseSections() {
+    for (std::vector<COFFYAML::Section>::iterator i = Obj.Sections.begin(),
+           e = Obj.Sections.end(); i != e; ++i) {
+      COFFYAML::Section &Sec = *i;
+
+      // If the name is less than 8 bytes, store it in place, otherwise
+      // store it in the string table.
+      StringRef Name = Sec.Name;
+
+      if (Name.size() <= COFF::NameSize) {
+        std::copy(Name.begin(), Name.end(), Sec.Header.Name);
+      } else {
+        // Add string to the string table and format the index for output.
+        unsigned Index = getStringIndex(Name);
+        std::string str = utostr(Index);
+        if (str.size() > 7) {
+          errs() << "String table got too large";
+          return false;
+        }
+        Sec.Header.Name[0] = '/';
+        std::copy(str.begin(), str.end(), Sec.Header.Name + 1);
+      }
+
+      Sec.Header.Characteristics |= (Log2_32(Sec.Alignment) + 1) << 20;
+    }
+    return true;
+  }
+
+  bool parseSymbols() {
+    for (std::vector<COFFYAML::Symbol>::iterator i = Obj.Symbols.begin(),
+           e = Obj.Symbols.end(); i != e; ++i) {
+      COFFYAML::Symbol &Sym = *i;
+
+      // If the name is less than 8 bytes, store it in place, otherwise
+      // store it in the string table.
+      StringRef Name = Sym.Name;
+      if (Name.size() <= COFF::NameSize) {
+        std::copy(Name.begin(), Name.end(), Sym.Header.Name);
+      } else {
+        // Add string to the string table and format the index for output.
+        unsigned Index = getStringIndex(Name);
+        *reinterpret_cast<support::aligned_ulittle32_t*>(
+            Sym.Header.Name + 4) = Index;
+      }
+
+      Sym.Header.Type = Sym.SimpleType;
+      Sym.Header.Type |= Sym.ComplexType << COFF::SCT_COMPLEX_TYPE_SHIFT;
+    }
+    return true;
+  }
+
+  bool parse() {
+    if (!parseSections())
+      return false;
+    if (!parseSymbols())
+      return false;
+    return true;
+  }
+
+  unsigned getStringIndex(StringRef Str) {
+    StringMap<unsigned>::iterator i = StringTableMap.find(Str);
+    if (i == StringTableMap.end()) {
+      unsigned Index = StringTable.size();
+      StringTable.append(Str.begin(), Str.end());
+      StringTable.push_back(0);
+      StringTableMap[Str] = Index;
+      return Index;
+    }
+    return i->second;
+  }
+
+  COFFYAML::Object &Obj;
+
+  StringMap<unsigned> StringTableMap;
+  std::string StringTable;
+};
+
+// Take a CP and assign addresses and sizes to everything. Returns false if the
+// layout is not valid to do.
+static bool layoutCOFF(COFFParser &CP) {
+  uint32_t SectionTableStart = 0;
+  uint32_t SectionTableSize  = 0;
+
+  // The section table starts immediately after the header, including the
+  // optional header.
+  SectionTableStart = sizeof(COFF::header) + CP.Obj.Header.SizeOfOptionalHeader;
+  SectionTableSize = sizeof(COFF::section) * CP.Obj.Sections.size();
+
+  uint32_t CurrentSectionDataOffset = SectionTableStart + SectionTableSize;
+
+  // Assign each section data address consecutively.
+  for (std::vector<COFFYAML::Section>::iterator i = CP.Obj.Sections.begin(),
+                                                e = CP.Obj.Sections.end();
+                                                i != e; ++i) {
+    StringRef SecData = i->SectionData.getHex();
+    if (!SecData.empty()) {
+      i->Header.SizeOfRawData = SecData.size()/2;
+      i->Header.PointerToRawData = CurrentSectionDataOffset;
+      CurrentSectionDataOffset += i->Header.SizeOfRawData;
+      if (!i->Relocations.empty()) {
+        i->Header.PointerToRelocations = CurrentSectionDataOffset;
+        i->Header.NumberOfRelocations = i->Relocations.size();
+        CurrentSectionDataOffset += i->Header.NumberOfRelocations *
+          COFF::RelocationSize;
+      }
+      // TODO: Handle alignment.
+    } else {
+      i->Header.SizeOfRawData = 0;
+      i->Header.PointerToRawData = 0;
+    }
+  }
+
+  uint32_t SymbolTableStart = CurrentSectionDataOffset;
+
+  // Calculate number of symbols.
+  uint32_t NumberOfSymbols = 0;
+  for (std::vector<COFFYAML::Symbol>::iterator i = CP.Obj.Symbols.begin(),
+                                               e = CP.Obj.Symbols.end();
+                                               i != e; ++i) {
+    unsigned AuxBytes = i->AuxiliaryData.getHex().size() / 2;
+    if (AuxBytes % COFF::SymbolSize != 0) {
+      errs() << "AuxiliaryData size not a multiple of symbol size!\n";
+      return false;
+    }
+    i->Header.NumberOfAuxSymbols = AuxBytes / COFF::SymbolSize;
+    NumberOfSymbols += 1 + i->Header.NumberOfAuxSymbols;
+  }
+
+  // Store all the allocated start addresses in the header.
+  CP.Obj.Header.NumberOfSections = CP.Obj.Sections.size();
+  CP.Obj.Header.NumberOfSymbols = NumberOfSymbols;
+  CP.Obj.Header.PointerToSymbolTable = SymbolTableStart;
+
+  *reinterpret_cast<support::ulittle32_t *>(&CP.StringTable[0])
+    = CP.StringTable.size();
+
+  return true;
+}
+
+template <typename value_type>
+struct binary_le_impl {
+  value_type Value;
+  binary_le_impl(value_type V) : Value(V) {}
+};
+
+template <typename value_type>
+raw_ostream &operator <<( raw_ostream &OS
+                        , const binary_le_impl<value_type> &BLE) {
+  char Buffer[sizeof(BLE.Value)];
+  support::endian::write<value_type, support::little, support::unaligned>(
+    Buffer, BLE.Value);
+  OS.write(Buffer, sizeof(BLE.Value));
+  return OS;
+}
+
+template <typename value_type>
+binary_le_impl<value_type> binary_le(value_type V) {
+  return binary_le_impl<value_type>(V);
+}
+
+static bool writeHexData(StringRef Data, raw_ostream &OS) {
+  unsigned Size = Data.size();
+  if (Size % 2)
+    return false;
+
+  for (unsigned I = 0; I != Size; I += 2) {
+    uint8_t Byte;
+    if (Data.substr(I,  2).getAsInteger(16, Byte))
+      return false;
+    OS.write(Byte);
+  }
+
+  return true;
+}
+
+bool writeCOFF(COFFParser &CP, raw_ostream &OS) {
+  OS << binary_le(CP.Obj.Header.Machine)
+     << binary_le(CP.Obj.Header.NumberOfSections)
+     << binary_le(CP.Obj.Header.TimeDateStamp)
+     << binary_le(CP.Obj.Header.PointerToSymbolTable)
+     << binary_le(CP.Obj.Header.NumberOfSymbols)
+     << binary_le(CP.Obj.Header.SizeOfOptionalHeader)
+     << binary_le(CP.Obj.Header.Characteristics);
+
+  // Output section table.
+  for (std::vector<COFFYAML::Section>::iterator i = CP.Obj.Sections.begin(),
+                                                e = CP.Obj.Sections.end();
+                                                i != e; ++i) {
+    OS.write(i->Header.Name, COFF::NameSize);
+    OS << binary_le(i->Header.VirtualSize)
+       << binary_le(i->Header.VirtualAddress)
+       << binary_le(i->Header.SizeOfRawData)
+       << binary_le(i->Header.PointerToRawData)
+       << binary_le(i->Header.PointerToRelocations)
+       << binary_le(i->Header.PointerToLineNumbers)
+       << binary_le(i->Header.NumberOfRelocations)
+       << binary_le(i->Header.NumberOfLineNumbers)
+       << binary_le(i->Header.Characteristics);
+  }
+
+  // Output section data.
+  for (std::vector<COFFYAML::Section>::iterator i = CP.Obj.Sections.begin(),
+                                                e = CP.Obj.Sections.end();
+                                                i != e; ++i) {
+    StringRef SecData = i->SectionData.getHex();
+    if (!SecData.empty()) {
+      if (!writeHexData(SecData, OS)) {
+        errs() << "SectionData must be a collection of pairs of hex bytes";
+        return false;
+      }
+    }
+    for (unsigned I2 = 0, E2 = i->Relocations.size(); I2 != E2; ++I2) {
+      const COFF::relocation &R = i->Relocations[I2];
+      OS << binary_le(R.VirtualAddress)
+         << binary_le(R.SymbolTableIndex)
+         << binary_le(R.Type);
+    }
+  }
+
+  // Output symbol table.
+
+  for (std::vector<COFFYAML::Symbol>::const_iterator i = CP.Obj.Symbols.begin(),
+                                                     e = CP.Obj.Symbols.end();
+                                                     i != e; ++i) {
+    OS.write(i->Header.Name, COFF::NameSize);
+    OS << binary_le(i->Header.Value)
+       << binary_le(i->Header.SectionNumber)
+       << binary_le(i->Header.Type)
+       << binary_le(i->Header.StorageClass)
+       << binary_le(i->Header.NumberOfAuxSymbols);
+    StringRef Data = i->AuxiliaryData.getHex();
+    if (!Data.empty()) {
+      if (!writeHexData(Data, OS)) {
+        errs() << "AuxiliaryData must be a collection of pairs of hex bytes";
+        return false;
+      }
+    }
+  }
+
+  // Output string table.
+  OS.write(&CP.StringTable[0], CP.StringTable.size());
+  return true;
+}
+
+int yaml2coff(llvm::raw_ostream &Out, llvm::MemoryBuffer *Buf) {
+  yaml::Input YIn(Buf->getBuffer());
+  COFFYAML::Object Doc;
+  YIn >> Doc;
+  if (YIn.error()) {
+    errs() << "yaml2obj: Failed to parse YAML file!\n";
+    return 1;
+  }
+
+  COFFParser CP(Doc);
+  if (!CP.parse()) {
+    errs() << "yaml2obj: Failed to parse YAML file!\n";
+    return 1;
+  }
+
+  if (!layoutCOFF(CP)) {
+    errs() << "yaml2obj: Failed to layout COFF file!\n";
+    return 1;
+  }
+  if (!writeCOFF(CP, Out)) {
+    errs() << "yaml2obj: Failed to write COFF file!\n";
+    return 1;
+  }
+  return 0;
+}