Revert "Re-enables JNI-direct for AOT on Power"

runtime/compiler/env/VMJ9.h

@@ -495,6 +495,8 @@ class TR_J9VMBase : public TR_FrontEnd
 
    virtual TR::TreeTop *lowerTree(TR::Compilation *, TR::Node *, TR::TreeTop *);
 
+   virtual bool canRelocateDirectNativeCalls() {return true; }
+
    virtual bool storeOffsetToArgumentsInVirtualIndirectThunks() { return false; }
 
 
@@ -1406,6 +1408,7 @@ class TR_J9SharedCacheVM : public TR_J9VM
    // replacing calls to isAOT
    virtual bool               canUseSymbolValidationManager() { return true; }
    virtual bool               supportsCodeCacheSnippets()                     { return false; }
+   virtual bool               canRelocateDirectNativeCalls()                  { return false; }
    virtual bool               needClassAndMethodPointerRelocations()          { return true; }
    virtual bool               inlinedAllocationsMustBeVerified()              { return true; }
    virtual bool               needRelocationsForHelpers()                     { return true; }

runtime/compiler/env/VMJ9Server.hpp

@@ -274,6 +274,7 @@ class TR_J9SharedCacheServerVM: public TR_J9ServerVM
    // replacing calls to isAOT
    virtual bool       canUseSymbolValidationManager() override                 { return true; }
    virtual bool       supportsCodeCacheSnippets() override                     { return false; }
+   virtual bool       canRelocateDirectNativeCalls() override                  { return false; }
    virtual bool       needClassAndMethodPointerRelocations() override          { return true; }
    virtual bool       inlinedAllocationsMustBeVerified() override              { return true; }
    virtual bool       needRelocationsForHelpers() override                     { return true; }

runtime/compiler/p/codegen/J9CodeGenerator.cpp

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2022 IBM Corp. and others
+ * Copyright (c) 2000, 2021 IBM Corp. and others
  *
  * This program and the accompanying materials are made available under
  * the terms of the Eclipse Public License 2.0 which accompanies this
@@ -747,7 +747,7 @@ J9::Power::CodeGenerator::deriveCallingLinkage(TR::Node *node, bool isIndirect)
    static char * disableDirectNativeCall = feGetEnv("TR_DisableDirectNativeCall");
 
    // Clean-up: the fej9 checking seemed unnecessary
-   if (!isIndirect && callee->isJNI() &&
+   if (!isIndirect && callee->isJNI() && fej9->canRelocateDirectNativeCalls() &&
        (node->isPreparedForDirectJNI() ||
         (disableDirectNativeCall == NULL && callee->getResolvedMethodSymbol()->canDirectNativeCall())))
       return self()->getLinkage(TR_J9JNILinkage);

runtime/compiler/p/codegen/J9CodeGenerator.hpp

@@ -111,7 +111,6 @@ class OMR_EXTENSIBLE CodeGenerator : public J9::CodeGenerator
     * \brief Determines whether the code generator supports stack allocations
     */
    bool supportsStackAllocations() { return true; }
-   bool supportsDirectJNICallsForAOT() { return true; }
 
    // See J9::CodeGenerator::guaranteesResolvedDirectDispatchForSVM
    bool guaranteesResolvedDirectDispatchForSVM() { return true; }