[Reland] Use llvm symbolizer for stack script.

llvm symbolizer is a more efficient symbolizer than addr2line, objdump,
etc.

In this cl, I 1)created a wrapper instance to interact with
llvm symbolizer, 2)made the stack script to use llvm symbolizer instance,
and then 3)added llvm symbolizer into isolated inputs.

Bug: 774267
Change-Id: I43d305b4c0c94be614ee4cad35b40f04b3d3ae20
Reviewed-on: https://chromium-review.googlesource.com/810007
Reviewed-by: John Budorick <jbudorick@chromium.org>
Reviewed-by: agrieve <agrieve@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Zhiling Huang <hzl@chromium.org>
Cr-Commit-Position: refs/heads/master@{#522520}

build/secondary/third_party/android_platform/development/scripts/BUILD.gn

@@ -13,9 +13,5 @@ group("stack_py") {
   sources = _py_files
   data = sources
 
-  data += [
-    "${android_tool_prefix}addr2line",
-    "${android_tool_prefix}objdump",
-    "${android_tool_prefix}c++filt",
-  ]
+  data += [ "//third_party/llvm-build/Release+Asserts/bin/llvm-symbolizer" ]
 }

third_party/android_platform/README.chromium

@@ -40,6 +40,10 @@ Added code to capture java stderr for better handling of native->java crashes.
 Fixed invalid using decl in logging header debug.h
 Only attempt to symbolize with ELF libraries.
 
+Changed the stack script to use llvm symbolizer instead of addr2line,
+objdump, etc, since llvm symbolizer is more efficient in finding
+function names, line numbers etc.
+
 Android relocation packing tool details:
     Copy sources from AOSP bionic/tools/relocation_packer
     Remove scripts that regenerate golden test data (not relevant here)

third_party/android_platform/development/scripts/stack

@@ -31,8 +31,13 @@ import sys
 sys.path.insert(0, os.path.join(os.path.dirname(__file__),
                                 os.pardir, os.pardir, os.pardir, os.pardir,
                                 'build', 'android'))
+
 from pylib import constants
 
+sys.path.insert(0, os.path.join(os.path.dirname(__file__),
+                                os.pardir, os.pardir, os.pardir, os.pardir,
+                                'tools', 'python'))
+import llvm_symbolizer
 
 DEFAULT_SYMROOT='/tmp/symbols'
 # From: https://source.android.com/source/build-numbers.html
@@ -225,10 +230,12 @@ def main(argv):
   print ("Reading Android symbols from: "
          + os.path.normpath(symbol.SYMBOLS_DIR))
   chrome_search_path = symbol.GetLibrarySearchPaths()
-  print ("Searching for Chrome symbols from within: "
-         + ':'.join((os.path.normpath(d) for d in chrome_search_path)))
-  stack_core.ConvertTrace(lines, load_vaddrs, more_info, fallback_monochrome,
-                          arch_defined)
+
+  with llvm_symbolizer.LLVMSymbolizer() as symbolizer:
+    print ("Searching for Chrome symbols from within: "
+           + ':'.join((os.path.normpath(d) for d in chrome_search_path)))
+    stack_core.ConvertTrace(lines, load_vaddrs, more_info, fallback_monochrome,
+                            arch_defined, symbolizer)
 
   if rootdir:
     # be a good citizen and clean up...os.rmdir and os.removedirs() don't work

third_party/android_platform/development/scripts/stack_core.py

@@ -158,7 +158,7 @@ def PrintDivider():
   print
   print '-----------------------------------------------------\n'
 
-def ConvertTrace(lines, load_vaddrs, more_info, fallback_monochrome, arch_defined):
+def ConvertTrace(lines, load_vaddrs, more_info, fallback_monochrome, arch_defined, llvm_symbolizer):
   """Convert strings containing native crash to a stack."""
   InitWidthRelatedLineMatchers()
 
@@ -189,7 +189,7 @@ def ConvertTrace(lines, load_vaddrs, more_info, fallback_monochrome, arch_define
       print ('Find ABI:' + arch)
       symbol.ARCH = arch
 
-  ResolveCrashSymbol(list(useful_log), more_info)
+  ResolveCrashSymbol(list(useful_log), more_info, llvm_symbolizer)
   end = time.time()
   logging.debug('Finished resolving symbols. Elapsed time: %.4fs',
                 (end - start))
@@ -304,7 +304,7 @@ def __call__(self, lines):
         useful_log.append(line)
     return useful_log, self._so_dirs
 
-def ResolveCrashSymbol(lines, more_info):
+def ResolveCrashSymbol(lines, more_info, llvm_symbolizer):
   """Convert unicode strings which contains native crash to a stack
   """
 
@@ -313,39 +313,15 @@ def ResolveCrashSymbol(lines, more_info):
   last_frame = -1
   pid = -1
 
-  # It is faster to get symbol information with a single call rather than with
-  # separate calls for each line. Since symbol.SymbolInformation caches results,
-  # we can extract all the addresses that we will want symbol information for
-  # from the log and call symbol.SymbolInformation so that the results are
-  # cached in the following lookups.
-  code_addresses = {}
-
   # Collects all java exception lines, keyed by pid for later output during
   # native crash handling.
   java_stderr_by_pid = {}
   for line in lines:
-    lib, address = None, None
-
-    match = _TRACE_LINE.match(line) or _DEBUG_TRACE_LINE.match(line)
-    if match:
-      address, lib = match.group('address', 'lib')
-
-    match = _VALUE_LINE.match(line)
-    if match and not _CODE_LINE.match(line):
-      (_0, _1, address, lib, _2, _3) = match.groups()
-
-    if lib:
-      code_addresses.setdefault(lib, set()).add(address)
-
     java_stderr_match = _JAVA_STDERR_LINE.search(line)
     if java_stderr_match:
       pid, msg = java_stderr_match.groups()
       java_stderr_by_pid.setdefault(pid, []).append(msg)
 
-  for lib in code_addresses:
-    symbol.SymbolInformationForSet(
-        symbol.TranslateLibPath(lib), code_addresses[lib], more_info)
-
   for line in lines:
     # AndroidFeedback adds zero width spaces into its crash reports. These
     # should be removed or the regular expresssions will fail to match.
@@ -410,46 +386,34 @@ def ResolveCrashSymbol(lines, more_info):
         logging.debug('Identified lib: %s' % area)
         # If a calls b which further calls c and c is inlined to b, we want to
         # display "a -> b -> c" in the stack trace instead of just "a -> c"
-        info = symbol.SymbolInformation(area, code_addr, more_info)
+        # To use llvm symbolizer, the hexadecimal address has to start with 0x.
+        info = llvm_symbolizer.GetSymbolInformation(
+            os.path.join(symbol.SYMBOLS_DIR, symbol.TranslateLibPath(area)),
+            '0x' + code_addr)
         logging.debug('symbol information: %s' % info)
         nest_count = len(info) - 1
-        for (source_symbol, source_location, object_symbol_with_offset) in info:
-          if not source_symbol:
-            if symbol_present:
-              source_symbol = symbol.CallCppFilt(symbol_name)
-            else:
-              source_symbol = UNKNOWN
-          if not source_location:
-            source_location = area
+        for source_symbol, source_location in info:
           if nest_count > 0:
             nest_count = nest_count - 1
             trace_lines.append(('v------>', source_symbol, source_location))
           else:
-            if not object_symbol_with_offset:
-              object_symbol_with_offset = source_symbol
             trace_lines.append((code_addr,
-                                object_symbol_with_offset,
+                                source_symbol,
                                 source_location))
     match = _VALUE_LINE.match(line)
     if match:
       (unused_, addr, value, area, symbol_present, symbol_name) = match.groups()
       if area == UNKNOWN or area == HEAP or area == STACK or not area:
         value_lines.append((addr, value, '', area))
       else:
-        info = symbol.SymbolInformation(area, value, more_info)
-        (source_symbol, source_location, object_symbol_with_offset) = info.pop()
-        if not source_symbol:
-          if symbol_present:
-            source_symbol = symbol.CallCppFilt(symbol_name)
-          else:
-            source_symbol = UNKNOWN
-        if not source_location:
-          source_location = area
-        if not object_symbol_with_offset:
-          object_symbol_with_offset = source_symbol
+        info = llvm_symbolizer.GetSymbolInformation(
+            os.path.join(symbol.SYMBOLS_DIR, symbol.TranslateLibPath(area)),
+            '0x' + code_addr)
+        source_symbol, source_location = info.pop()
+
         value_lines.append((addr,
                             value,
-                            object_symbol_with_offset,
+                            source_symbol,
                             source_location))
 
   java_lines = []