Intercept JNI invocation of String.<init> methods.
libmono uses JNI AllocObject and CallNonvirtualVoidMethod to create and
initialize a string instead of using the recommended NewObject. This
change adds an intercept to change the String.<init> call to a
StringFactory call instead. Then, it uses the object id of the original
string object referrer and maps it to the result of the StringFactory.
Bug: 21288130
(cherry picked from commit 15e9ad1d028d7f12cb598b075453173532a00d91)
Change-Id: I3421c43722c07397da4a398c2ca9110e1d40bcfa
diff --git a/runtime/reflection.cc b/runtime/reflection.cc
index 49e1b8e..d321d27 100644
--- a/runtime/reflection.cc
+++ b/runtime/reflection.cc
@@ -21,6 +21,7 @@
#include "common_throws.h"
#include "dex_file-inl.h"
#include "entrypoints/entrypoint_utils.h"
+#include "indirect_reference_table-inl.h"
#include "jni_internal.h"
#include "mirror/abstract_method.h"
#include "mirror/art_method-inl.h"
@@ -449,6 +450,11 @@
}
mirror::ArtMethod* method = soa.DecodeMethod(mid);
+ bool is_string_init = method->GetDeclaringClass()->IsStringClass() && method->IsConstructor();
+ if (is_string_init) {
+ // Replace calls to String.<init> with equivalent StringFactory call.
+ method = soa.DecodeMethod(WellKnownClasses::StringInitToStringFactoryMethodID(mid));
+ }
mirror::Object* receiver = method->IsStatic() ? nullptr : soa.Decode<mirror::Object*>(obj);
uint32_t shorty_len = 0;
const char* shorty = method->GetShorty(&shorty_len);
@@ -456,11 +462,15 @@
ArgArray arg_array(shorty, shorty_len);
arg_array.BuildArgArrayFromVarArgs(soa, receiver, args);
InvokeWithArgArray(soa, method, &arg_array, &result, shorty);
+ if (is_string_init) {
+ // For string init, remap original receiver to StringFactory result.
+ soa.Self()->GetJniEnv()->locals.Update(obj, result.GetL());
+ }
return result;
}
-JValue InvokeWithJValues(const ScopedObjectAccessAlreadyRunnable& soa, mirror::Object* receiver,
- jmethodID mid, jvalue* args) {
+JValue InvokeWithJValues(const ScopedObjectAccessAlreadyRunnable& soa, jobject obj, jmethodID mid,
+ jvalue* args) {
// We want to make sure that the stack is not within a small distance from the
// protected region in case we are calling into a leaf function whose stack
// check has been elided.
@@ -470,17 +480,27 @@
}
mirror::ArtMethod* method = soa.DecodeMethod(mid);
+ bool is_string_init = method->GetDeclaringClass()->IsStringClass() && method->IsConstructor();
+ if (is_string_init) {
+ // Replace calls to String.<init> with equivalent StringFactory call.
+ method = soa.DecodeMethod(WellKnownClasses::StringInitToStringFactoryMethodID(mid));
+ }
+ mirror::Object* receiver = method->IsStatic() ? nullptr : soa.Decode<mirror::Object*>(obj);
uint32_t shorty_len = 0;
const char* shorty = method->GetShorty(&shorty_len);
JValue result;
ArgArray arg_array(shorty, shorty_len);
arg_array.BuildArgArrayFromJValues(soa, receiver, args);
InvokeWithArgArray(soa, method, &arg_array, &result, shorty);
+ if (is_string_init) {
+ // For string init, remap original receiver to StringFactory result.
+ soa.Self()->GetJniEnv()->locals.Update(obj, result.GetL());
+ }
return result;
}
JValue InvokeVirtualOrInterfaceWithJValues(const ScopedObjectAccessAlreadyRunnable& soa,
- mirror::Object* receiver, jmethodID mid, jvalue* args) {
+ jobject obj, jmethodID mid, jvalue* args) {
// We want to make sure that the stack is not within a small distance from the
// protected region in case we are calling into a leaf function whose stack
// check has been elided.
@@ -489,13 +509,24 @@
return JValue();
}
+ mirror::Object* receiver = soa.Decode<mirror::Object*>(obj);
mirror::ArtMethod* method = FindVirtualMethod(receiver, soa.DecodeMethod(mid));
+ bool is_string_init = method->GetDeclaringClass()->IsStringClass() && method->IsConstructor();
+ if (is_string_init) {
+ // Replace calls to String.<init> with equivalent StringFactory call.
+ method = soa.DecodeMethod(WellKnownClasses::StringInitToStringFactoryMethodID(mid));
+ receiver = nullptr;
+ }
uint32_t shorty_len = 0;
const char* shorty = method->GetShorty(&shorty_len);
JValue result;
ArgArray arg_array(shorty, shorty_len);
arg_array.BuildArgArrayFromJValues(soa, receiver, args);
InvokeWithArgArray(soa, method, &arg_array, &result, shorty);
+ if (is_string_init) {
+ // For string init, remap original receiver to StringFactory result.
+ soa.Self()->GetJniEnv()->locals.Update(obj, result.GetL());
+ }
return result;
}
@@ -511,12 +542,22 @@
mirror::Object* receiver = soa.Decode<mirror::Object*>(obj);
mirror::ArtMethod* method = FindVirtualMethod(receiver, soa.DecodeMethod(mid));
+ bool is_string_init = method->GetDeclaringClass()->IsStringClass() && method->IsConstructor();
+ if (is_string_init) {
+ // Replace calls to String.<init> with equivalent StringFactory call.
+ method = soa.DecodeMethod(WellKnownClasses::StringInitToStringFactoryMethodID(mid));
+ receiver = nullptr;
+ }
uint32_t shorty_len = 0;
const char* shorty = method->GetShorty(&shorty_len);
JValue result;
ArgArray arg_array(shorty, shorty_len);
arg_array.BuildArgArrayFromVarArgs(soa, receiver, args);
InvokeWithArgArray(soa, method, &arg_array, &result, shorty);
+ if (is_string_init) {
+ // For string init, remap original receiver to StringFactory result.
+ soa.Self()->GetJniEnv()->locals.Update(obj, result.GetL());
+ }
return result;
}