Populating is_multiple in google_breakpad::StackFrame from symbol files.

This is needed in order to properly detect and highlight frames that
correspond to multiple functions, for example as the result of identical
code folding by the linker.

Bug: google-breakpad:751
Change-Id: I2ee7c147fcff6493c2454383ad5422b38269759a
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/3471034
Reviewed-by: Joshua Peraza <jperaza@chromium.org>

src/google_breakpad/processor/stack_frame.h

@@ -63,7 +63,8 @@ struct StackFrame {
         source_file_name(),
         source_line(0),
         source_line_base(),
-        trust(FRAME_TRUST_NONE){}
+        trust(FRAME_TRUST_NONE),
+        is_multiple(false) {}
   virtual ~StackFrame() {}
 
   // Return a string describing how this stack frame was found
@@ -140,6 +141,12 @@ struct StackFrame {
   // Amount of trust the stack walker has in the instruction pointer
   // of this frame.
   FrameTrust trust;
+
+  // True if the frame corresponds to multiple functions, for example as the
+  // result of identical code folding by the linker. In that case the function
+  // name, filename, etc. information above represents the state of an arbitrary
+  // one of these functions.
+  bool is_multiple;
 };
 
 }  // namespace google_breakpad

src/processor/basic_source_line_resolver.cc

@@ -319,6 +319,7 @@ void BasicSourceLineResolver::Module::LookupAddress(
       address >= function_base && address - function_base < function_size) {
     frame->function_name = func->name;
     frame->function_base = frame->module->base_address() + function_base;
+    frame->is_multiple = func->is_multiple;
 
     linked_ptr<Line> line;
     MemAddr line_base;
@@ -341,6 +342,7 @@ void BasicSourceLineResolver::Module::LookupAddress(
              (!func.get() || public_address > function_base)) {
     frame->function_name = public_symbol->name;
     frame->function_base = frame->module->base_address() + public_address;
+    frame->is_multiple = public_symbol->is_multiple;
   }
 }
 

src/processor/basic_source_line_resolver_unittest.cc

@@ -52,7 +52,6 @@ using google_breakpad::CodeModule;
 using google_breakpad::MemoryRegion;
 using google_breakpad::StackFrame;
 using google_breakpad::WindowsFrameInfo;
-using google_breakpad::linked_ptr;
 using google_breakpad::scoped_ptr;
 using google_breakpad::SymbolParseHelper;
 
@@ -93,12 +92,12 @@ class MockMemoryRegion: public MemoryRegion {
   }
   bool GetMemoryAtAddress(uint64_t address, uint32_t* value) const {
     switch (address) {
-      case 0x10008: *value = 0x98ecadc3; break; // saved %ebx
+      case 0x10008: *value = 0x98ecadc3; break;  // saved %ebx
-      case 0x1000c: *value = 0x878f7524; break; // saved %esi
+      case 0x1000c: *value = 0x878f7524; break;  // saved %esi
-      case 0x10010: *value = 0x6312f9a5; break; // saved %edi
+      case 0x10010: *value = 0x6312f9a5; break;  // saved %edi
-      case 0x10014: *value = 0x10038;    break; // caller's %ebp
+      case 0x10014: *value = 0x10038;    break;  // caller's %ebp
-      case 0x10018: *value = 0xf6438648; break; // return address
+      case 0x10018: *value = 0xf6438648; break;  // return address
-      default: *value = 0xdeadbeef;      break; // junk
+      default: *value = 0xdeadbeef;      break;  // junk
     }
     return true;
   }
@@ -164,7 +163,7 @@ static void ClearSourceLineInfo(StackFrame* frame) {
 }
 
 class TestBasicSourceLineResolver : public ::testing::Test {
-public:
+ public:
   void SetUp() {
     testdata_dir = string(getenv("srcdir") ? getenv("srcdir") : ".") +
                          "/src/processor/testdata";
@@ -196,6 +195,7 @@ TEST_F(TestBasicSourceLineResolver, TestLoadAndResolve)
   ASSERT_TRUE(frame.source_file_name.empty());
   ASSERT_EQ(frame.source_line, 0);
   ASSERT_EQ(frame.source_line_base, 0U);
+  EXPECT_EQ(frame.is_multiple, false);
 
   frame.module = &module1;
   resolver.FillSourceLineInfo(&frame, nullptr);
@@ -206,6 +206,7 @@ TEST_F(TestBasicSourceLineResolver, TestLoadAndResolve)
   ASSERT_EQ(frame.source_file_name, "file1_1.cc");
   ASSERT_EQ(frame.source_line, 44);
   ASSERT_EQ(frame.source_line_base, 0x1000U);
+  EXPECT_EQ(frame.is_multiple, true);
   windows_frame_info.reset(resolver.FindWindowsFrameInfo(&frame));
   ASSERT_TRUE(windows_frame_info.get());
   ASSERT_EQ(windows_frame_info->type_, WindowsFrameInfo::STACK_INFO_FRAME_DATA);
@@ -344,6 +345,7 @@ TEST_F(TestBasicSourceLineResolver, TestLoadAndResolve)
   frame.module = &module1;
   resolver.FillSourceLineInfo(&frame, nullptr);
   ASSERT_EQ(frame.function_name, string("PublicSymbol"));
+  EXPECT_EQ(frame.is_multiple, true);
 
   frame.instruction = 0x4000;
   frame.module = &module1;
@@ -360,6 +362,7 @@ TEST_F(TestBasicSourceLineResolver, TestLoadAndResolve)
   ASSERT_EQ(frame.source_file_name, "file2_2.cc");
   ASSERT_EQ(frame.source_line, 21);
   ASSERT_EQ(frame.source_line_base, 0x2180U);
+  EXPECT_EQ(frame.is_multiple, false);
   windows_frame_info.reset(resolver.FindWindowsFrameInfo(&frame));
   ASSERT_TRUE(windows_frame_info.get());
   ASSERT_EQ(windows_frame_info->type_, WindowsFrameInfo::STACK_INFO_FRAME_DATA);
@@ -368,6 +371,7 @@ TEST_F(TestBasicSourceLineResolver, TestLoadAndResolve)
   frame.instruction = 0x216f;
   resolver.FillSourceLineInfo(&frame, nullptr);
   ASSERT_EQ(frame.function_name, "Public2_1");
+  EXPECT_EQ(frame.is_multiple, false);
 
   ClearSourceLineInfo(&frame);
   frame.instruction = 0x219f;
@@ -431,6 +435,7 @@ TEST_F(TestBasicSourceLineResolver, TestLoadAndResolveOldInlines) {
   ASSERT_EQ(frame.source_file_name, "linux_inline.cpp");
   ASSERT_EQ(frame.source_line, 42);
   ASSERT_EQ(frame.source_line_base, 0x161b6U);
+  EXPECT_EQ(frame.is_multiple, false);
 
   ASSERT_EQ(inlined_frames.size(), 3UL);
 
@@ -475,6 +480,7 @@ TEST_F(TestBasicSourceLineResolver, TestLoadAndResolveNewInlines) {
   ASSERT_EQ(frame.source_file_name, "a.cpp");
   ASSERT_EQ(frame.source_line, 42);
   ASSERT_EQ(frame.source_line_base, 0x161b6U);
+  EXPECT_EQ(frame.is_multiple, false);
 
   ASSERT_EQ(inlined_frames.size(), 3UL);
 

src/processor/fast_source_line_resolver.cc

@@ -88,6 +88,7 @@ void FastSourceLineResolver::Module::LookupAddress(
     func->CopyFrom(func_ptr);
     frame->function_name = func->name;
     frame->function_base = frame->module->base_address() + function_base;
+    frame->is_multiple = func->is_multiple;
 
     scoped_ptr<Line> line(new Line);
     const Line* line_ptr = 0;
@@ -112,6 +113,7 @@ void FastSourceLineResolver::Module::LookupAddress(
     public_symbol->CopyFrom(public_symbol_ptr);
     frame->function_name = public_symbol->name;
     frame->function_base = frame->module->base_address() + public_address;
+    frame->is_multiple = public_symbol->is_multiple;
   }
 }
 

src/processor/fast_source_line_resolver_unittest.cc

@@ -64,7 +64,6 @@ using google_breakpad::CodeModule;
 using google_breakpad::MemoryRegion;
 using google_breakpad::StackFrame;
 using google_breakpad::WindowsFrameInfo;
-using google_breakpad::linked_ptr;
 using google_breakpad::scoped_ptr;
 
 class TestCodeModule : public CodeModule {
@@ -224,6 +223,7 @@ TEST_F(TestFastSourceLineResolver, TestLoadAndResolve) {
   ASSERT_TRUE(frame.source_file_name.empty());
   ASSERT_EQ(frame.source_line, 0);
   ASSERT_EQ(frame.source_line_base, 0U);
+  ASSERT_EQ(frame.is_multiple, false);
 
   frame.module = &module1;
   fast_resolver.FillSourceLineInfo(&frame, nullptr);
@@ -234,6 +234,7 @@ TEST_F(TestFastSourceLineResolver, TestLoadAndResolve) {
   ASSERT_EQ(frame.source_file_name, "file1_1.cc");
   ASSERT_EQ(frame.source_line, 44);
   ASSERT_EQ(frame.source_line_base, 0x1000U);
+  ASSERT_EQ(frame.is_multiple, true);
   windows_frame_info.reset(fast_resolver.FindWindowsFrameInfo(&frame));
   ASSERT_TRUE(windows_frame_info.get());
   ASSERT_FALSE(windows_frame_info->allocates_base_pointer);
@@ -371,6 +372,7 @@ TEST_F(TestFastSourceLineResolver, TestLoadAndResolve) {
   frame.module = &module1;
   fast_resolver.FillSourceLineInfo(&frame, nullptr);
   ASSERT_EQ(frame.function_name, string("PublicSymbol"));
+  EXPECT_EQ(frame.is_multiple, true);
 
   frame.instruction = 0x4000;
   frame.module = &module1;
@@ -387,6 +389,7 @@ TEST_F(TestFastSourceLineResolver, TestLoadAndResolve) {
   ASSERT_EQ(frame.source_file_name, "file2_2.cc");
   ASSERT_EQ(frame.source_line, 21);
   ASSERT_EQ(frame.source_line_base, 0x2180U);
+  ASSERT_EQ(frame.is_multiple, false);
   windows_frame_info.reset(fast_resolver.FindWindowsFrameInfo(&frame));
   ASSERT_TRUE(windows_frame_info.get());
   ASSERT_EQ(windows_frame_info->type_, WindowsFrameInfo::STACK_INFO_FRAME_DATA);
@@ -395,6 +398,7 @@ TEST_F(TestFastSourceLineResolver, TestLoadAndResolve) {
   frame.instruction = 0x216f;
   fast_resolver.FillSourceLineInfo(&frame, nullptr);
   ASSERT_EQ(frame.function_name, "Public2_1");
+  EXPECT_EQ(frame.is_multiple, false);
 
   ClearSourceLineInfo(&frame);
   frame.instruction = 0x219f;
@@ -433,6 +437,7 @@ TEST_F(TestFastSourceLineResolver, TestLoadAndResolveOldInlines) {
   ASSERT_EQ(frame.source_file_name, "linux_inline.cpp");
   ASSERT_EQ(frame.source_line, 42);
   ASSERT_EQ(frame.source_line_base, 0x161b6U);
+  ASSERT_EQ(frame.is_multiple, false);
 
   ASSERT_EQ(inlined_frames.size(), 3UL);
 
@@ -484,6 +489,7 @@ TEST_F(TestFastSourceLineResolver, TestLoadAndResolveNewInlines) {
   ASSERT_EQ(frame.source_file_name, "a.cpp");
   ASSERT_EQ(frame.source_line, 42);
   ASSERT_EQ(frame.source_line_base, 0x161b6U);
+  ASSERT_EQ(frame.is_multiple, false);
 
   ASSERT_EQ(inlined_frames.size(), 3UL);
 

src/processor/testdata/module1.out

@@ -3,7 +3,7 @@ INFO CODE_ID FFFFFFFF module1.exe
 FILE 1 file1_1.cc
 FILE 2 file1_2.cc
 FILE 3 file1_3.cc
-FUNC 1000 c 0 Function1_1
+FUNC m 1000 c 0 Function1_1
 1000 4 44 1
 1004 4 45 1
 1008 4 46 1
@@ -14,7 +14,7 @@ FUNC 1200 100 8 Function1_3
 FUNC 1300 100 c Function1_4
 FUNC 2000 0 0 Test_Zero_Size_Function_Is_Ignored
 2000 4 88 2
-PUBLIC 2800 0 PublicSymbol
+PUBLIC m 2800 0 PublicSymbol
 FUNC 3000 7000 42 LargeFunction
 3000 7000 4098359 3
 STACK WIN 4 1000 c 1 0 0 0 0 0 1 $eip 4 + ^ = $esp $ebp 8 + = $ebp $ebp ^ =