1 files changed, 44 insertions, 7 deletions

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.cc b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.cc
index 5664543a7f1..88bd2f8d896 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.cc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.cc
@@ -95,8 +95,47 @@ const char *Symbolizer::ModuleNameOwner::GetOwnedCopy(const char *str) {
   return last_match_;
 }
 
+bool Symbolizer::FindModuleNameAndOffsetForAddress(uptr address,
+                                                   const char **module_name,
+                                                   uptr *module_offset) {
+  LoadedModule *module = FindModuleForAddress(address);
+  if (module == 0)
+    return false;
+  *module_name = module->full_name();
+  *module_offset = address - module->base_address();
+  return true;
+}
+
+LoadedModule *Symbolizer::FindModuleForAddress(uptr address) {
+  bool modules_were_reloaded = false;
+  if (!modules_fresh_) {
+    for (uptr i = 0; i < n_modules_; i++)
+      modules_[i].clear();
+    n_modules_ = PlatformGetListOfModules(modules_, kMaxNumberOfModules);
+    CHECK_GT(n_modules_, 0);
+    CHECK_LT(n_modules_, kMaxNumberOfModules);
+    modules_fresh_ = true;
+    modules_were_reloaded = true;
+  }
+  for (uptr i = 0; i < n_modules_; i++) {
+    if (modules_[i].containsAddress(address)) {
+      return &modules_[i];
+    }
+  }
+  // Reload the modules and look up again, if we haven't tried it yet.
+  if (!modules_were_reloaded) {
+    // FIXME: set modules_fresh_ from dlopen()/dlclose() interceptors.
+    // It's too aggressive to reload the list of modules each time we fail
+    // to find a module for a given address.
+    modules_fresh_ = false;
+    return FindModuleForAddress(address);
+  }
+  return 0;
+}
+
 Symbolizer::Symbolizer(IntrusiveList<SymbolizerTool> tools)
-    : module_names_(&mu_), tools_(tools), start_hook_(0), end_hook_(0) {}
+    : module_names_(&mu_), n_modules_(0), modules_fresh_(false), tools_(tools),
+      start_hook_(0), end_hook_(0) {}
 
 Symbolizer::SymbolizerScope::SymbolizerScope(const Symbolizer *sym)
     : sym_(sym) {
@@ -114,8 +153,7 @@ SymbolizedStack *Symbolizer::SymbolizePC(uptr addr) {
   const char *module_name;
   uptr module_offset;
   SymbolizedStack *res = SymbolizedStack::New(addr);
-  if (!PlatformFindModuleNameAndOffsetForAddress(addr, &module_name,
-                                                 &module_offset))
+  if (!FindModuleNameAndOffsetForAddress(addr, &module_name, &module_offset))
     return res;
   // Always fill data about module name and offset.
   res->info.FillModuleInfo(module_name, module_offset);
@@ -133,8 +171,7 @@ bool Symbolizer::SymbolizeData(uptr addr, DataInfo *info) {
   BlockingMutexLock l(&mu_);
   const char *module_name;
   uptr module_offset;
-  if (!PlatformFindModuleNameAndOffsetForAddress(addr, &module_name,
-                                                 &module_offset))
+  if (!FindModuleNameAndOffsetForAddress(addr, &module_name, &module_offset))
     return false;
   info->Clear();
   info->module = internal_strdup(module_name);
@@ -153,8 +190,8 @@ bool Symbolizer::GetModuleNameAndOffsetForPC(uptr pc, const char **module_name,
                                              uptr *module_address) {
   BlockingMutexLock l(&mu_);
   const char *internal_module_name = nullptr;
-  if (!PlatformFindModuleNameAndOffsetForAddress(pc, &internal_module_name,
-                                                 module_address))
+  if (!FindModuleNameAndOffsetForAddress(pc, &internal_module_name,
+                                         module_address))
     return false;
 
   if (module_name)