Add a pass to insert artificial debug info when the method miss it

Reviewed By: NTillmann

Differential Revision: D66043130

fbshipit-source-id: 6d07d03399b5c75e0e86291a61feb30e5ffdf070

Makefile.am

@@ -419,6 +419,7 @@ libopt_la_SOURCES = \
 	opt/final_inline/FinalInlineV2.cpp \
 	opt/fully-qualify-layouts/FullyQualifyLayouts.cpp \
 	opt/init-classes/InitClassLoweringPass.cpp \
+	opt/insert_debug_info/InsertDebugInfoPass.cpp \
 	opt/insert-source-blocks/InsertSourceBlocks.cpp \
 	opt/instrument/BlockInstrument.cpp \
 	opt/instrument/Instrument.cpp \

opt/insert_debug_info/InsertDebugInfoPass.cpp

@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include "InsertDebugInfoPass.h"
+
+#include "ControlFlow.h"
+#include "PassManager.h"
+#include "Show.h"
+#include "Walkers.h"
+
+void InsertDebugInfoPass::run_pass(DexStoresVector& stores,
+                                   ConfigFiles& conf,
+                                   PassManager& mgr) {
+  std::atomic<uint32_t> patched_method = 0;
+  walk::parallel::code(
+      build_class_scope(stores), [&](DexMethod* method, IRCode& code) {
+        always_assert(code.editable_cfg_built());
+        bool has_position = false;
+        auto& cfg = code.cfg();
+        for (auto* block : cfg.blocks()) {
+          for (auto it = block->begin(); it != block->end(); it++) {
+            if (it->type == MFLOW_POSITION) {
+              has_position = true;
+              break;
+            }
+          }
+        }
+        if (has_position) {
+          return;
+        }
+        patched_method++;
+        always_assert_log(!code.get_debug_item(),
+                          "%s has no DexPosition, but has a DexDebugItem %s",
+                          SHOW(method),
+                          SHOW(code.cfg()));
+        code.set_debug_item(std::make_unique<DexDebugItem>());
+        auto* block = cfg.entry_block();
+        auto last_param = block->get_last_param_loading_insn();
+        auto artificial_pos = std::make_unique<DexPosition>(
+            DexString::make_string(show_deobfuscated(method)),
+            DexString::make_string("UnknownSource"), 0);
+        if (last_param == block->end()) {
+          cfg.insert_before(block->to_cfg_instruction_iterator(
+                                block->get_first_non_param_loading_insn()),
+                            std::move(artificial_pos));
+        } else {
+          cfg.insert_after(block->to_cfg_instruction_iterator(
+                               block->get_last_param_loading_insn()),
+                           std::move(artificial_pos));
+        }
+      });
+
+  mgr.set_metric("patched_method", patched_method);
+}
+
+static InsertDebugInfoPass s_pass;

opt/insert_debug_info/InsertDebugInfoPass.h

@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include "Pass.h"
+
+class InsertDebugInfoPass : public Pass {
+ public:
+  InsertDebugInfoPass() : Pass("InsertDebugInfoPass") {}
+
+  redex_properties::PropertyInteractions get_property_interactions()
+      const override {
+    using namespace redex_properties::interactions;
+    using namespace redex_properties::names;
+    return {
+        {DexLimitsObeyed, Preserves},
+        {UltralightCodePatterns, Preserves},
+    };
+  }
+
+  void run_pass(DexStoresVector&, ConfigFiles&, PassManager&) override;
+};