commit e41823bb894165a504c21b139a81445f6f55d4df
author Spyridoula Gravani <sgravani@apple.com> Wed Jun 14 00:17:55 2017 +0000
committer Spyridoula Gravani <sgravani@apple.com> Wed Jun 14 00:17:55 2017 +0000
tree b04f20f5b73882b653ce7745ba89f67c05061ad6
parent 41def9b72c104408f2711dbfc82b27098c705fa0

Added partial verification for .apple_names accelerator table in llvm-dwarfdump output.

This patch adds code which verifies that each bucket in the .apple_names
accelerator table is either empty or has a valid hash index.

Differential Revision: https://reviews.llvm.org/D34177

llvm-svn: 305344

llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp b/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp
index 97b52f0..87009bf 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp
@@ -55,6 +55,13 @@
   return true;
 }
 
+uint32_t DWARFAcceleratorTable::getNumBuckets() { return Hdr.NumBuckets; }
+uint32_t DWARFAcceleratorTable::getNumHashes() { return Hdr.NumHashes; }
+uint32_t DWARFAcceleratorTable::getSizeHdr() { return sizeof(Hdr); }
+uint32_t DWARFAcceleratorTable::getHeaderDataLength() {
+  return Hdr.HeaderDataLength;
+}
+
 LLVM_DUMP_METHOD void DWARFAcceleratorTable::dump(raw_ostream &OS) const {
   // Dump the header.
   OS << "Magic = " << format("0x%08x", Hdr.Magic) << '\n'

llvm/lib/DebugInfo/DWARF/DWARFContext.cpp

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
index fb48253..ff9230d 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -678,8 +678,13 @@
     if (!verifier.handleDebugLine())
       Success = false;
   }
+  if (DumpType == DIDT_All || DumpType == DIDT_AppleNames) {
+    if (!verifier.handleAppleNames())
+      Success = false;
+  }
   return Success;
 }
+
 const DWARFUnitIndex &DWARFContext::getCUIndex() {
   if (CUIndex)
     return *CUIndex;

llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
index 8a54429..a6240fb 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
@@ -14,6 +14,7 @@
 #include "llvm/DebugInfo/DWARF/DWARFDie.h"
 #include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
 #include "llvm/DebugInfo/DWARF/DWARFSection.h"
+#include "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
 #include "llvm/Support/raw_ostream.h"
 #include <map>
 #include <set>
@@ -275,3 +276,36 @@
   verifyDebugLineRows();
   return NumDebugLineErrors == 0;
 }
+
+bool DWARFVerifier::handleAppleNames() {
+  NumAppleNamesErrors = 0;
+  OS << "Verifying .apple_names...\n";
+
+  DataExtractor AppleNamesSection(DCtx.getAppleNamesSection().Data,
+                                  DCtx.isLittleEndian(), 0);
+  DataExtractor StrData(DCtx.getStringSection(), DCtx.isLittleEndian(), 0);
+  DWARFAcceleratorTable AppleNames(AppleNamesSection, StrData,
+                                   DCtx.getAppleNamesSection().Relocs);
+
+  if (!AppleNames.extract()) {
+    OS << "error: cannot extract .apple_names accelerator table\n";
+    return false;
+  }
+
+  // Verify that all buckets have a valid hash index or are empty
+  uint32_t NumBuckets = AppleNames.getNumBuckets();
+  uint32_t NumHashes = AppleNames.getNumHashes();
+
+  uint32_t BucketsOffset =
+      AppleNames.getSizeHdr() + AppleNames.getHeaderDataLength();
+
+  for (uint32_t BucketIdx = 0; BucketIdx < NumBuckets; ++BucketIdx) {
+    uint32_t HashIdx = AppleNamesSection.getU32(&BucketsOffset);
+    if (HashIdx >= NumHashes && HashIdx != UINT32_MAX) {
+      OS << format("error: Bucket[%d] has invalid hash index: [%d]\n",
+                   BucketIdx, HashIdx);
+      ++NumAppleNamesErrors;
+    }
+  }
+  return NumAppleNamesErrors == 0;
+}