Do not create symbols for [DEDUPED] methods.
The incorrect method name keeps confusing developers, despite the tag.
However, around half the time, the deduped methods share either the
same class name or method name, so include it in the name if possible.
Bug: 32949969
Test: printf the generated method names.
Change-Id: I9cc6f16da0a91d93aa05df5476011bf180d626d9
diff --git a/compiler/debug/elf_symtab_writer.h b/compiler/debug/elf_symtab_writer.h
index c09639e..ac8c812 100644
--- a/compiler/debug/elf_symtab_writer.h
+++ b/compiler/debug/elf_symtab_writer.h
@@ -19,12 +19,14 @@
#include <map>
#include <unordered_set>
+#include <unordered_map>
#include "base/utils.h"
#include "debug/debug_info.h"
#include "debug/method_debug_info.h"
-#include "dex/dex_file-inl.h"
#include "dex/code_item_accessors.h"
+#include "dex/descriptors_names.h"
+#include "dex/dex_file-inl.h"
#include "elf/elf_builder.h"
namespace art {
@@ -44,6 +46,39 @@
// by this ELF file (currently mmapped inside the .dex section).
constexpr const char* kDexFileSymbolName = "$dexfile";
+// Return common parts of method names; shared by all methods in the given set.
+// (e.g. "[DEDUPED] ?.<init>" or "com.android.icu.charset.CharsetEncoderICU.?")
+static void GetDedupedName(const std::vector<const MethodDebugInfo*>& methods, std::string* out) {
+ DCHECK(!methods.empty());
+ const MethodDebugInfo* first = methods.front();
+ auto is_same_class = [&first](const MethodDebugInfo* mi) {
+ DCHECK(mi->dex_file != nullptr);
+ return mi->dex_file == first->dex_file && mi->class_def_index == first->class_def_index;
+ };
+ auto is_same_method_name = [&first](const MethodDebugInfo* mi) {
+ return strcmp(mi->dex_file->GetMethodName(mi->dex_method_index),
+ first->dex_file->GetMethodName(first->dex_method_index)) == 0;
+ };
+ bool all_same_class = std::all_of(methods.begin(), methods.end(), is_same_class);
+ bool all_same_method_name = std::all_of(methods.begin(), methods.end(), is_same_method_name);
+ *out = "[DEDUPED]";
+ if (all_same_class || all_same_method_name) {
+ *out += ' ';
+ if (all_same_class) {
+ auto& dex_class_def = first->dex_file->GetClassDef(first->class_def_index);
+ AppendPrettyDescriptor(first->dex_file->GetClassDescriptor(dex_class_def), &*out);
+ } else {
+ *out += '?';
+ }
+ *out += '.';
+ if (all_same_method_name) {
+ *out += first->dex_file->GetMethodName(first->dex_method_index);
+ } else {
+ *out += '?';
+ }
+ }
+}
+
template <typename ElfTypes>
static void WriteDebugSymbols(ElfBuilder<ElfTypes>* builder,
bool mini_debug_info,
@@ -71,6 +106,15 @@
}
}
+ // Create list of deduped methods per function address.
+ // We have to do it separately since the first method does not have the deduped flag.
+ std::unordered_map<uint64_t, std::vector<const MethodDebugInfo*>> deduped_methods;
+ for (const MethodDebugInfo& info : debug_info.compiled_methods) {
+ if (deduped_addresses.find(info.code_address) != deduped_addresses.end()) {
+ deduped_methods[info.code_address].push_back(&info);
+ }
+ }
+
strtab->Start();
strtab->Write(""); // strtab should start with empty string.
// Generate ARM mapping symbols. ELF local symbols must be added first.
@@ -89,7 +133,10 @@
DCHECK(info.dex_file != nullptr);
std::string name = info.dex_file->PrettyMethod(info.dex_method_index, !mini_debug_info);
if (deduped_addresses.find(info.code_address) != deduped_addresses.end()) {
- name = "[DEDUPED] " + name;
+ // Create method name common to all the deduped methods if possible.
+ // Around half of the time, there is either common class or method name.
+ // NB: We used to return one method at random with tag, but developers found it confusing.
+ GetDedupedName(deduped_methods[info.code_address], &name);
}
name_offset = strtab->Write(name);
}
diff --git a/libdexfile/dex/dex_file-inl.h b/libdexfile/dex/dex_file-inl.h
index 61c4593..0e1fb68 100644
--- a/libdexfile/dex/dex_file-inl.h
+++ b/libdexfile/dex/dex_file-inl.h
@@ -130,6 +130,10 @@
return StringDataAndUtf16LengthByIdx(method_id.name_idx_, utf_length);
}
+inline const char* DexFile::GetMethodName(uint32_t idx) const {
+ return StringDataByIdx(GetMethodId(idx).name_idx_);
+}
+
inline const char* DexFile::GetMethodName(uint32_t idx, uint32_t* utf_length) const {
return StringDataAndUtf16LengthByIdx(GetMethodId(idx).name_idx_, utf_length);
}
diff --git a/libdexfile/dex/dex_file.h b/libdexfile/dex/dex_file.h
index a21e538..a28856a 100644
--- a/libdexfile/dex/dex_file.h
+++ b/libdexfile/dex/dex_file.h
@@ -387,6 +387,7 @@
// Returns the name of a method id.
const char* GetMethodName(const dex::MethodId& method_id) const;
const char* GetMethodName(const dex::MethodId& method_id, uint32_t* utf_length) const;
+ const char* GetMethodName(uint32_t idx) const;
const char* GetMethodName(uint32_t idx, uint32_t* utf_length) const;
// Returns the shorty of a method by its index.