8248524: [JVMCI] Memory corruption / segfault during NumPy installation

Reviewed-by: kvn

src/hotspot/share/jvmci/jvmciEnv.cpp

@@ -621,26 +621,13 @@ const char* JVMCIEnv::as_utf8_string(JVMCIObject str) {
   } else {
     JNIAccessMark jni(this);
     int length = jni()->GetStringLength(str.as_jstring());
-    char* result = NEW_RESOURCE_ARRAY(char, length + 1);
+    int utf8_length = jni()->GetStringUTFLength(str.as_jstring());
+    char* result = NEW_RESOURCE_ARRAY(char, utf8_length + 1);
     jni()->GetStringUTFRegion(str.as_jstring(), 0, length, result);
     return result;
   }
 }
 
-char* JVMCIEnv::as_utf8_string(JVMCIObject str, char* buf, int buflen) {
-  if (is_hotspot()) {
-    return java_lang_String::as_utf8_string(HotSpotJVMCI::resolve(str), buf, buflen);
-  } else {
-    JNIAccessMark jni(this);
-    int length = jni()->GetStringLength(str.as_jstring());
-    if (length >= buflen) {
-      length = buflen;
-    }
-    jni()->GetStringUTFRegion(str.as_jstring(), 0, length, buf);
-    return buf;
-  }
-}
-
 #define DO_THROW(name)                             \
 void JVMCIEnv::throw_##name(const char* msg) {     \
   if (is_hotspot()) {                              \

src/hotspot/share/jvmci/jvmciEnv.hpp

@@ -261,7 +261,6 @@ class JVMCIEnv : public ResourceObj {
   JVMCIObject create_box(BasicType type, jvalue* value, JVMCI_TRAPS);
 
   const char* as_utf8_string(JVMCIObject str);
-  char* as_utf8_string(JVMCIObject str, char* buf, int buflen);
 
   JVMCIObject create_string(Symbol* str, JVMCI_TRAPS) {
     JVMCIObject s = create_string(str->as_C_string(), JVMCI_CHECK_(JVMCIObject()));