1 files changed, 227 insertions, 0 deletions
diff --git a/toolkit/crashreporter/minidump-analyzer/Win64ModuleUnwindMetadata.cpp b/toolkit/crashreporter/minidump-analyzer/Win64ModuleUnwindMetadata.cpp
new file mode 100644
index 0000000000..4978415e86
--- /dev/null
+++ b/toolkit/crashreporter/minidump-analyzer/Win64ModuleUnwindMetadata.cpp
@@ -0,0 +1,227 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#if XP_WIN && HAVE_64BIT_BUILD
+
+#  include "Win64ModuleUnwindMetadata.h"
+
+#  include "MinidumpAnalyzerUtils.h"
+
+#  include <windows.h>
+#  include <winnt.h>
+#  include <imagehlp.h>
+#  include <iostream>
+#  include <set>
+#  include <sstream>
+#  include <string>
+
+#  include "mozilla/WindowsUnwindInfo.h"
+
+using namespace mozilla;
+
+namespace CrashReporter {
+
+ModuleUnwindParser::~ModuleUnwindParser() {
+  if (mImg) {
+    ImageUnload(mImg);
+  }
+}
+
+void* ModuleUnwindParser::RvaToVa(ULONG aRva) {
+  return ImageRvaToVa(mImg->FileHeader, mImg->MappedAddress, aRva,
+                      &mImg->LastRvaSection);
+}
+
+ModuleUnwindParser::ModuleUnwindParser(const std::string& aPath)
+    : mPath(aPath) {
+  // Convert wchar to native charset because ImageLoad only takes
+  // a PSTR as input.
+  std::string code_file = UTF8ToMBCS(aPath);
+
+  mImg = ImageLoad((PSTR)code_file.c_str(), NULL);
+  if (!mImg || !mImg->FileHeader) {
+    return;
+  }
+
+  PIMAGE_OPTIONAL_HEADER64 optional_header = &mImg->FileHeader->OptionalHeader;
+  if (optional_header->Magic != IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
+    return;
+  }
+
+  DWORD exception_rva =
+      optional_header->DataDirectory[IMAGE_DIRECTORY_ENTRY_EXCEPTION]
+          .VirtualAddress;
+
+  DWORD exception_size =
+      optional_header->DataDirectory[IMAGE_DIRECTORY_ENTRY_EXCEPTION].Size;
+
+  auto funcs = (PIMAGE_RUNTIME_FUNCTION_ENTRY)RvaToVa(exception_rva);
+  if (!funcs) {
+    return;
+  }
+
+  for (DWORD i = 0; i < exception_size / sizeof(*funcs); i++) {
+    mUnwindMap[funcs[i].BeginAddress] = &funcs[i];
+  }
+}
+
+bool ModuleUnwindParser::GenerateCFIForFunction(
+    IMAGE_RUNTIME_FUNCTION_ENTRY& aFunc, UnwindCFI& aRet) {
+  DWORD unwind_rva = aFunc.UnwindInfoAddress;
+  // Holds RVA to all visited IMAGE_RUNTIME_FUNCTION_ENTRY, to avoid
+  // circular references.
+  std::set<DWORD> visited;
+
+  // Follow chained function entries
+  while (unwind_rva & 0x1) {
+    unwind_rva ^= 0x1;
+
+    if (visited.end() != visited.find(unwind_rva)) {
+      return false;
+    }
+    visited.insert(unwind_rva);
+
+    auto chained_func = (PIMAGE_RUNTIME_FUNCTION_ENTRY)RvaToVa(unwind_rva);
+    if (!chained_func) {
+      return false;
+    }
+    unwind_rva = chained_func->UnwindInfoAddress;
+  }
+
+  visited.insert(unwind_rva);
+
+  auto unwind_info = (UnwindInfo*)RvaToVa(unwind_rva);
+  if (!unwind_info) {
+    return false;
+  }
+
+  DWORD stack_size = 8;  // minimal stack size is 8 for RIP
+  DWORD rip_offset = 8;
+  do {
+    for (uint8_t c = 0; c < unwind_info->count_of_codes; c++) {
+      UnwindCode* unwind_code = &unwind_info->unwind_code[c];
+      switch (unwind_code->unwind_operation_code) {
+        case UWOP_PUSH_NONVOL: {
+          stack_size += 8;
+          break;
+        }
+        case UWOP_ALLOC_LARGE: {
+          if (unwind_code->operation_info == 0) {
+            c++;
+            if (c < unwind_info->count_of_codes) {
+              stack_size += (unwind_code + 1)->frame_offset * 8;
+            }
+          } else {
+            c += 2;
+            if (c < unwind_info->count_of_codes) {
+              stack_size += (unwind_code + 1)->frame_offset |
+                            ((unwind_code + 2)->frame_offset << 16);
+            }
+          }
+          break;
+        }
+        case UWOP_ALLOC_SMALL: {
+          stack_size += unwind_code->operation_info * 8 + 8;
+          break;
+        }
+        case UWOP_SET_FPREG:
+          // To correctly track RSP when it's been transferred to another
+          // register, we would need to emit CFI records for every unwind op.
+          // For simplicity, don't emit CFI records for this function as
+          // we know it will be incorrect after this point.
+          return false;
+        case UWOP_SAVE_NONVOL:
+        case UWOP_SAVE_XMM:  // also v2 UWOP_EPILOG
+        case UWOP_SAVE_XMM128: {
+          c++;  // skip slot with offset
+          break;
+        }
+        case UWOP_SAVE_NONVOL_FAR:
+        case UWOP_SAVE_XMM_FAR:  // also v2 UWOP_SPARE
+        case UWOP_SAVE_XMM128_FAR: {
+          c += 2;  // skip 2 slots with offset
+          break;
+        }
+        case UWOP_PUSH_MACHFRAME: {
+          if (unwind_code->operation_info) {
+            stack_size += 88;
+          } else {
+            stack_size += 80;
+          }
+          rip_offset += 80;
+          break;
+        }
+        default: {
+          return false;
+        }
+      }
+    }
+
+    if (unwind_info->flags & UNW_FLAG_CHAININFO) {
+      auto chained_func = (PIMAGE_RUNTIME_FUNCTION_ENTRY)((
+          unwind_info->unwind_code + ((unwind_info->count_of_codes + 1) & ~1)));
+
+      if (visited.end() != visited.find(chained_func->UnwindInfoAddress)) {
+        return false;  // Circular reference
+      }
+
+      visited.insert(chained_func->UnwindInfoAddress);
+
+      unwind_info = (UnwindInfo*)RvaToVa(chained_func->UnwindInfoAddress);
+    } else {
+      unwind_info = nullptr;
+    }
+  } while (unwind_info);
+
+  aRet.beginAddress = aFunc.BeginAddress;
+  aRet.size = aFunc.EndAddress - aFunc.BeginAddress;
+  aRet.stackSize = stack_size;
+  aRet.ripOffset = rip_offset;
+  return true;
+}
+
+// For unit testing we sometimes need any address that's valid in this module.
+// Just return the first address we know of.
+DWORD
+ModuleUnwindParser::GetAnyOffsetAddr() const {
+  if (mUnwindMap.size() < 1) {
+    return 0;
+  }
+  return mUnwindMap.begin()->first;
+}
+
+bool ModuleUnwindParser::GetCFI(DWORD aAddress, UnwindCFI& aRet) {
+  // Figure out the begin address of the requested address.
+  auto itUW = mUnwindMap.lower_bound(aAddress + 1);
+  if (itUW == mUnwindMap.begin()) {
+    return false;  // address before this module.
+  }
+  --itUW;
+
+  // Ensure that the function entry is big enough to contain this address.
+  IMAGE_RUNTIME_FUNCTION_ENTRY& func = *itUW->second;
+  if (aAddress > func.EndAddress) {
+    return false;
+  }
+
+  // Do we have CFI for this function already?
+  auto itCFI = mCFIMap.find(aAddress);
+  if (itCFI != mCFIMap.end()) {
+    aRet = itCFI->second;
+    return true;
+  }
+
+  // No, generate it.
+  if (!GenerateCFIForFunction(func, aRet)) {
+    return false;
+  }
+
+  mCFIMap[func.BeginAddress] = aRet;
+  return true;
+}
+
+}  // namespace CrashReporter
+
+#endif  // XP_WIN && HAVE_64BIT_BUILD