CoCalc -- J9MethodSymbol.cpp

GitHub Repository: PojavLauncherTeam/openj9
Path: blob/master/runtime/compiler/il/J9MethodSymbol.cpp
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/*******************************************************************************
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 * Copyright (c) 2000, 2021 IBM Corp. and others
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 *
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 * This program and the accompanying materials are made available under
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 * the terms of the Eclipse Public License 2.0 which accompanies this
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 * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
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 * or the Apache License, Version 2.0 which accompanies this distribution and
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 * is available at https://www.apache.org/licenses/LICENSE-2.0.
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 *
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 * This Source Code may also be made available under the following
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 * Secondary Licenses when the conditions for such availability set
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 * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
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 * General Public License, version 2 with the GNU Classpath
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 * Exception [1] and GNU General Public License, version 2 with the
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 * OpenJDK Assembly Exception [2].
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 *
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 * [1] https://www.gnu.org/software/classpath/license.html
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 * [2] http://openjdk.java.net/legal/assembly-exception.html
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 *
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 * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception
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 *******************************************************************************/
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#include "compile/Compilation.hpp"
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#include "env/TRMemory.hpp"
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#include "il/DataTypes.hpp"
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#include "il/MethodSymbol.hpp"
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#include "infra/Assert.hpp"
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#include "runtime/J9Runtime.hpp"
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/**
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 * Return true if this method is pure ie no side-effects.
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 *
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 * Currently only runtime helpers and recognized methods can be true.
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 */
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bool
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J9::MethodSymbol::isPureFunction()
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   {
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   switch(self()->getRecognizedMethod())
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      {
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      case TR::java_lang_Math_abs_I:
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      case TR::java_lang_Math_abs_L:
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      case TR::java_lang_Math_abs_F:
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      case TR::java_lang_Math_abs_D:
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      case TR::java_lang_Math_acos:
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      case TR::java_lang_Math_asin:
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      case TR::java_lang_Math_atan:
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      case TR::java_lang_Math_atan2:
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      case TR::java_lang_Math_cbrt:
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      case TR::java_lang_Math_ceil:
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      case TR::java_lang_Math_copySign_F:
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      case TR::java_lang_Math_copySign_D:
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      case TR::java_lang_Math_cos:
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      case TR::java_lang_Math_cosh:
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      case TR::java_lang_Math_exp:
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      case TR::java_lang_Math_expm1:
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      case TR::java_lang_Math_floor:
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      case TR::java_lang_Math_hypot:
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      case TR::java_lang_Math_IEEEremainder:
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      case TR::java_lang_Math_log:
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      case TR::java_lang_Math_log10:
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      case TR::java_lang_Math_log1p:
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      case TR::java_lang_Math_max_I:
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      case TR::java_lang_Math_max_L:
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      case TR::java_lang_Math_max_F:
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      case TR::java_lang_Math_max_D:
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      case TR::java_lang_Math_min_I:
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      case TR::java_lang_Math_min_L:
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      case TR::java_lang_Math_min_F:
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      case TR::java_lang_Math_min_D:
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      case TR::java_lang_Math_nextAfter_F:
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      case TR::java_lang_Math_nextAfter_D:
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      case TR::java_lang_Math_pow:
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      case TR::java_lang_Math_rint:
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      case TR::java_lang_Math_round_F:
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      case TR::java_lang_Math_round_D:
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      case TR::java_lang_Math_scalb_F:
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      case TR::java_lang_Math_scalb_D:
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      case TR::java_lang_Math_sin:
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      case TR::java_lang_Math_sinh:
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      case TR::java_lang_Math_sqrt:
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      case TR::java_lang_Math_tan:
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      case TR::java_lang_Math_tanh:
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      case TR::java_lang_ref_Reference_reachabilityFence:
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      case TR::java_lang_StrictMath_acos:
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      case TR::java_lang_StrictMath_asin:
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      case TR::java_lang_StrictMath_atan:
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      case TR::java_lang_StrictMath_atan2:
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      case TR::java_lang_StrictMath_cbrt:
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      case TR::java_lang_StrictMath_ceil:
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      case TR::java_lang_StrictMath_copySign_F:
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      case TR::java_lang_StrictMath_copySign_D:
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      case TR::java_lang_StrictMath_cos:
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      case TR::java_lang_StrictMath_cosh:
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      case TR::java_lang_StrictMath_exp:
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      case TR::java_lang_StrictMath_expm1:
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      case TR::java_lang_StrictMath_floor:
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      case TR::java_lang_StrictMath_hypot:
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      case TR::java_lang_StrictMath_IEEEremainder:
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      case TR::java_lang_StrictMath_log:
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      case TR::java_lang_StrictMath_log10:
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      case TR::java_lang_StrictMath_log1p:
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      case TR::java_lang_StrictMath_nextAfter_F:
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      case TR::java_lang_StrictMath_nextAfter_D:
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      case TR::java_lang_StrictMath_pow:
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      case TR::java_lang_StrictMath_random:
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      case TR::java_lang_StrictMath_round_F:
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      case TR::java_lang_StrictMath_round_D:
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      case TR::java_lang_StrictMath_scalb_F:
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      case TR::java_lang_StrictMath_scalb_D:
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      case TR::java_lang_StrictMath_rint:
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      case TR::java_lang_StrictMath_sin:
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      case TR::java_lang_StrictMath_sinh:
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      case TR::java_lang_StrictMath_sqrt:
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      case TR::java_lang_StrictMath_tan:
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      case TR::java_lang_StrictMath_tanh:
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      case TR::java_nio_Bits_keepAlive:
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         /*
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      case TR::java_math_BigDecimal_valueOf:
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      case TR::java_math_BigDecimal_add:
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      case TR::java_math_BigDecimal_subtract:
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      case TR::java_math_BigDecimal_multiply:
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      case TR::java_math_BigInteger_add:
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      case TR::java_math_BigInteger_subtract:
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      case TR::java_math_BigInteger_multiply:
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         */
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         return true;
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      default:
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         return false;
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      }
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   return false;
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   }
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/**
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 * Returns true if the function call will not yield to OSR point.
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 * 
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 * An example of kind of function which can go in the list would be recognized calls with
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 * NOP calls or the one that are guaranteed to be inlined by codegenerator. 
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 */
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bool 
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J9::MethodSymbol::functionCallDoesNotYieldOSR()
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   {
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   switch(self()->getRecognizedMethod())
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      {
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      case TR::java_lang_ref_Reference_reachabilityFence:
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      case TR::java_nio_Bits_keepAlive:
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         return true;
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      default:
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         return OMR::MethodSymbolConnector::functionCallDoesNotYieldOSR(); 
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      }
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   return false;
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   }
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// Which recognized methods are known to have no valid null checks
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//
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static TR::RecognizedMethod canSkipNullChecks[] =
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   {
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   // NOTE!! add methods whose checks can be skipped by sov library to the beginning of the list (see stopMethod below)
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   TR::java_lang_invoke_FilterArgumentsHandle_invokeExact,
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   TR::java_lang_invoke_MethodHandle_undoCustomizationLogic,
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   TR::java_lang_invoke_CollectHandle_invokeExact,
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   TR::java_util_ArrayList_add,
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   TR::java_util_ArrayList_ensureCapacity,
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   TR::java_util_ArrayList_get,
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#if JAVA_SPEC_VERSION < 17
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   TR::java_lang_String_trim,
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   TR::java_lang_String_replace,
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   TR::java_lang_String_charAt,
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   TR::java_lang_String_charAtInternal_I,
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   TR::java_lang_String_charAtInternal_IB,
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   TR::java_lang_String_hashCodeImplCompressed,
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   TR::java_lang_String_hashCodeImplDecompressed,
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   TR::java_lang_String_length,
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   TR::java_lang_String_lengthInternal,
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   //TR::java_lang_String_toLowerCase,
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   //TR::java_lang_String_toUpperCase,
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   //TR::java_lang_String_toLowerCaseCore,
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   //TR::java_lang_String_toUpperCaseCore,
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   TR::java_lang_String_equalsIgnoreCase,
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   TR::java_lang_String_indexOf_fast,
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   TR::java_lang_String_isCompressed,
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   TR::java_lang_String_coder,
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   TR::java_lang_String_isLatin1,
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   TR::java_lang_String_init_int_String_int_String_String,
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   TR::java_lang_String_init_int_int_char_boolean,
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   TR::java_lang_String_split_str_int,
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#endif
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   TR::java_lang_StringBuffer_capacityInternal,
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   TR::java_lang_StringBuffer_lengthInternalUnsynchronized,
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   TR::java_lang_StringBuilder_capacityInternal,
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   TR::java_lang_StringBuilder_lengthInternal,
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   TR::java_lang_StringUTF16_charAt,
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   TR::java_lang_StringUTF16_checkIndex,
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   TR::java_lang_StringUTF16_length,
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   TR::java_util_Hashtable_clone,
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   TR::java_util_Hashtable_contains,
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   TR::java_util_HashtableHashEnumerator_hasMoreElements,
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   TR::java_util_HashtableHashEnumerator_nextElement,
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   TR::java_util_HashMap_resize,
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   TR::java_util_HashMapHashIterator_nextNode,
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   //TR::java_util_Vector_addElement,
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   TR::java_math_BigDecimal_longString1C,
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   TR::java_math_BigDecimal_longString2,
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   TR::java_util_EnumMap__nec_,
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   TR::java_util_TreeMapUnboundedValueIterator_next,
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   TR::java_util_TreeMapSubMap_setFirstKey,
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   TR::java_util_TreeMapSubMap_setLastKey,
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   TR::java_nio_Bits_getCharB,
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   TR::java_nio_Bits_getCharL,
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   TR::java_nio_Bits_getShortB,
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   TR::java_nio_Bits_getShortL,
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   TR::java_nio_Bits_getIntB,
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   TR::java_nio_Bits_getIntL,
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   TR::java_nio_Bits_getLongB,
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   TR::java_nio_Bits_getLongL,
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   TR::java_nio_HeapByteBuffer__get,
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   TR::java_nio_HeapByteBuffer_put,
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   TR::unknownMethod
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   };
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bool
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J9::MethodSymbol::safeToSkipNullChecks()
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   {
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   TR::RecognizedMethod methodId = self()->getRecognizedMethod();
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   if (methodId == TR::unknownMethod)
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      return false;
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   for (int i = 0; canSkipNullChecks[i] != TR::unknownMethod; ++i)
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      if (canSkipNullChecks[i] == methodId)
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         return true;
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   return false;
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   }
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// Which recognized methods are known to have no valid bound checks
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//
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static TR::RecognizedMethod canSkipBoundChecks[] =
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   {
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   // NOTE!! add methods whose checks can be skipped by sov library to the beginning of the list (see stopMethod below)
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   //TR::java_util_ArrayList_add,
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   //TR::java_util_ArrayList_remove,
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   //TR::java_util_ArrayList_ensureCapacity,
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   //TR::java_util_ArrayList_get,
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   TR::java_lang_Character_toLowerCase,
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   TR::java_lang_invoke_FilterArgumentsHandle_invokeExact,
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   TR::java_lang_invoke_CollectHandle_invokeExact,
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   TR::java_lang_String_trim,
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   TR::java_lang_String_charAt,
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   TR::java_lang_String_charAtInternal_I,
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   TR::java_lang_String_charAtInternal_IB,
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   TR::java_lang_String_indexOf_String,
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   TR::java_lang_String_indexOf_String_int,
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   TR::java_lang_String_indexOf_native,
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   TR::java_lang_String_indexOf_fast,
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   TR::java_lang_String_replace,
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   TR::java_lang_String_compareTo,
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   TR::java_lang_String_lastIndexOf,
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   TR::java_lang_String_toLowerCase,
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   TR::java_lang_String_toUpperCase,
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   TR::java_lang_String_toLowerCaseCore,
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   TR::java_lang_String_toUpperCaseCore,
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   TR::java_lang_String_regionMatches,
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   TR::java_lang_String_regionMatches_bool,
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   TR::java_lang_String_regionMatchesInternal,
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   TR::java_lang_String_equalsIgnoreCase,
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   TR::java_lang_String_compareToIgnoreCase,
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   TR::java_lang_String_hashCodeImplCompressed,
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   TR::java_lang_String_hashCodeImplDecompressed,
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   TR::java_lang_String_unsafeCharAt,
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   TR::java_lang_String_split_str_int,
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   TR::java_lang_String_startsWith,
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   TR::java_lang_StringUTF16_compareCodePointCI,
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   TR::java_lang_StringUTF16_compareToCIImpl,
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   TR::java_lang_StringUTF16_compareValues,
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   TR::java_util_Hashtable_get,
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   TR::java_util_Hashtable_put,
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   TR::java_util_Hashtable_clone,
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   TR::java_util_Hashtable_rehash,
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   TR::java_util_Hashtable_remove,
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   TR::java_util_Hashtable_contains,
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   TR::java_util_Hashtable_getEntry,
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   TR::java_util_HashtableHashEnumerator_hasMoreElements,
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   TR::java_util_HashtableHashEnumerator_nextElement,
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   TR::java_util_HashMap_getNode,
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   TR::java_util_HashMap_resize,
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   //TR::java_util_HashMapHashIterator_nextNode,  /* Unsafe if the Iterator is being incorrectly used (concurrent execution) */
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   TR::java_util_HashMapHashIterator_init,        /* Safe because the object is only visible by one thread when init() is executing */
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   TR::java_util_EnumMap_put,
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   TR::java_util_EnumMap_typeCheck,
290
   TR::java_util_EnumMap__init_,
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   TR::java_util_EnumMap__nec_,
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   TR::java_util_TreeMap_all,
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   TR::java_util_TreeMap_rbInsert,
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   TR::java_math_BigDecimal_longString1C,
295
   TR::java_math_BigDecimal_longString2,
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   TR::java_util_TreeMapUnboundedValueIterator_next,
297
   TR::java_util_TreeMapSubMap_setFirstKey,
298
   TR::java_util_TreeMapSubMap_setLastKey,
299
   TR::java_util_HashMap_get,
300
   TR::java_util_HashMap_findNonNullKeyEntry,
301
   TR::java_util_HashMap_putImpl,
302
   TR::java_lang_String_init_int_String_int_String_String,
303
   TR::java_lang_String_init_int_int_char_boolean,
304
   TR::java_nio_Bits_getCharB,
305
   TR::java_nio_Bits_getCharL,
306
   TR::java_nio_Bits_getShortB,
307
   TR::java_nio_Bits_getShortL,
308
   TR::java_nio_Bits_getIntB,
309
   TR::java_nio_Bits_getIntL,
310
   TR::java_nio_Bits_getLongB,
311
   TR::java_nio_Bits_getLongL,
312
   TR::java_nio_HeapByteBuffer__get,
313
   TR::java_nio_HeapByteBuffer_put,
314
   TR::unknownMethod
315
   };
316

317
bool
318
J9::MethodSymbol::safeToSkipBoundChecks()
319
   {
320
   TR::RecognizedMethod methodId = self()->getRecognizedMethod();
321
   if (methodId == TR::unknownMethod)
322
      return false;
323

324
   for (int i = 0; canSkipBoundChecks[i] != TR::unknownMethod; ++i)
325
      if (canSkipBoundChecks[i] == methodId)
326
         return true;
327

328
   return false;
329
   }
330

331
// Which recognized methods are known to have no valid div checks
332
//
333
static TR::RecognizedMethod canSkipDivChecks[] =
334
   {
335
   TR::java_util_Hashtable_get,
336
   TR::java_util_Hashtable_put,
337
   TR::java_util_Hashtable_rehash,
338
   TR::java_util_Hashtable_remove,
339
   TR::java_util_Hashtable_getEntry,
340
   TR::unknownMethod
341
   };
342

343
bool
344
J9::MethodSymbol::safeToSkipDivChecks()
345
   {
346
   TR::RecognizedMethod methodId = self()->getRecognizedMethod();
347
   if (methodId == TR::unknownMethod)
348
      return false;
349

350
   for (int i = 0; canSkipDivChecks[i] != TR::unknownMethod; ++i)
351
      if (canSkipDivChecks[i] == methodId)
352
         return true;
353

354
   return false;
355
   }
356

357

358
// Which recognized methods are known to have no valid checkcasts
359
//
360
static TR::RecognizedMethod canSkipCheckCasts[] =
361
   {
362
   TR::java_util_ArrayList_ensureCapacity,
363
   TR::java_util_HashMap_resize,
364
   TR::java_util_HashMapHashIterator_nextNode,
365
   TR::java_util_Hashtable_clone,
366
   TR::java_util_Hashtable_putAll,
367
   TR::unknownMethod
368
   };
369

370
bool
371
J9::MethodSymbol::safeToSkipCheckCasts()
372
   {
373
   TR::RecognizedMethod methodId = self()->getRecognizedMethod();
374
   if (methodId == TR::unknownMethod)
375
      return false;
376

377
   for (int i = 0; canSkipCheckCasts[i] != TR::unknownMethod; ++i)
378
      if (canSkipCheckCasts[i] == methodId)
379
         return true;
380

381
   return false;
382
   }
383

384

385
// Which recognized methods are known to have no valid array store checks
386
//
387
static TR::RecognizedMethod canSkipArrayStoreChecks[] =
388
   {
389
   TR::java_lang_invoke_CollectHandle_invokeExact,
390
   TR::java_util_ArrayList_add,
391
   TR::java_util_ArrayList_ensureCapacity,
392
   TR::java_util_ArrayList_get,
393
   TR::java_util_ArrayList_remove,
394
   TR::java_util_ArrayList_set,
395
   TR::java_util_Hashtable_get,
396
   TR::java_util_Hashtable_put,
397
   TR::java_util_Hashtable_clone,
398
   TR::java_util_Hashtable_putAll,
399
   TR::java_util_Hashtable_rehash,
400
   TR::java_util_Hashtable_remove,
401
   TR::java_util_Hashtable_contains,
402
   TR::java_util_Hashtable_getEntry,
403
   TR::java_util_Hashtable_getEnumeration,
404
   TR::java_util_Hashtable_elements,
405
   TR::java_util_HashtableHashEnumerator_hasMoreElements,
406
   TR::java_util_HashtableHashEnumerator_nextElement,
407
   TR::java_util_HashMap_rehash,
408
   TR::java_util_HashMap_analyzeMap,
409
   TR::java_util_HashMap_calculateCapacity,
410
   TR::java_util_HashMap_findNullKeyEntry,
411
   TR::java_util_HashMap_get,
412
   TR::java_util_HashMap_findNonNullKeyEntry,
413
   TR::java_util_HashMap_putImpl,
414
   TR::java_util_HashMap_resize,
415
   TR::java_util_HashMapHashIterator_nextNode,
416
   TR::java_util_Vector_addElement,
417
   TR::java_util_Vector_contains,
418
   TR::java_util_Vector_subList,
419
   TR::java_util_TreeMap_rbInsert,
420
   TR::java_util_TreeMapUnboundedValueIterator_next,
421
   TR::java_util_TreeMapSubMap_setLastKey,
422
   TR::java_util_TreeMapSubMap_setFirstKey,
423
   TR::java_util_concurrent_ConcurrentHashMap_addCount,
424
   TR::java_util_concurrent_ConcurrentHashMap_tryPresize,
425
   TR::java_util_concurrent_ConcurrentHashMap_transfer,
426
   TR::java_util_concurrent_ConcurrentHashMap_fullAddCount,
427
   TR::java_util_concurrent_ConcurrentHashMap_helpTransfer,
428
   TR::java_util_concurrent_ConcurrentHashMap_initTable,
429
   TR::java_util_concurrent_ConcurrentHashMap_tabAt,
430
   TR::java_util_concurrent_ConcurrentHashMap_casTabAt,
431
   TR::java_util_concurrent_ConcurrentHashMap_setTabAt,
432
   TR::java_util_concurrent_ConcurrentHashMap_TreeBin_lockRoot,
433
   TR::java_util_concurrent_ConcurrentHashMap_TreeBin_contendedLock,
434
   TR::java_util_concurrent_ConcurrentHashMap_TreeBin_find,
435
   TR::java_util_TreeMap_all,
436
   TR::java_util_EnumMap_put,
437
   TR::java_util_EnumMap_typeCheck,
438
   TR::java_util_EnumMap__init_,
439
   TR::java_util_EnumMap__nec_,
440
   TR::java_util_HashMap_all,
441
   TR::java_util_ArrayList_all,
442
   TR::java_util_Hashtable_all,
443
   TR::java_util_concurrent_ConcurrentHashMap_all,
444
   TR::java_util_Vector_all,
445
   TR::unknownMethod
446
   };
447

448
bool
449
J9::MethodSymbol::safeToSkipArrayStoreChecks()
450
   {
451
   TR::RecognizedMethod methodId = self()->getRecognizedMethod();
452
   if (methodId == TR::unknownMethod)
453
      return false;
454

455
   for (int i = 0; canSkipArrayStoreChecks[i] != TR::unknownMethod; ++i)
456
      if (canSkipArrayStoreChecks[i] == methodId)
457
         return true;
458

459
   return false;
460
   }
461

462

463
// Which recognized methods are known to require no checking when lowering to TR::arraycopy
464
//
465
static TR::RecognizedMethod canSkipChecksOnArrayCopies[] =
466
   {
467
   // NOTE!! add methods whose checks can be skipped by sov library to the beginning of the list (see stopMethod below)
468
   //TR::java_util_ArrayList_ensureCapacity,
469
   //TR::java_util_ArrayList_remove,   /* ArrayList is NOT synchronized and therefore it's unsafe to remove checks! */
470
   TR::java_lang_Character_toLowerCase,
471
   TR::java_lang_String_concat,
472
   TR::java_lang_String_replace,
473
   TR::java_lang_String_toLowerCase,
474
   TR::java_lang_String_toUpperCase,
475
   TR::java_lang_String_toLowerCaseCore,
476
   TR::java_lang_String_toUpperCaseCore,
477
   TR::java_lang_String_toCharArray,
478
   TR::java_lang_StringBuffer_append,
479
   TR::java_lang_StringBuffer_ensureCapacityImpl,
480
   TR::java_lang_String_init_int_String_int_String_String,
481
   TR::java_lang_String_init_int_int_char_boolean,
482
   TR::java_util_HashMap_resize,
483
   TR::java_util_HashMapHashIterator_nextNode,
484
   TR::unknownMethod
485
   };
486

487
// These are logically the same as the above (canSkipChecksOnArrayCopies).
488
// I've broken them out so that we can selectively disable this group
489
// with the TR_DisableExtraCopyOfOpts env var. If/when these prove to be safe
490
// they can be migrated into the main group.
491
static TR::RecognizedMethod extraCanSkipChecksOnArrayCopies[] =
492
   {
493
   TR::java_util_Arrays_copyOf_byte,
494
   TR::java_util_Arrays_copyOf_short,
495
   TR::java_util_Arrays_copyOf_char,
496
   TR::java_util_Arrays_copyOf_boolean,
497
   TR::java_util_Arrays_copyOf_int,
498
   TR::java_util_Arrays_copyOf_long,
499
   TR::java_util_Arrays_copyOf_float,
500
   TR::java_util_Arrays_copyOf_double,
501
   TR::java_util_Arrays_copyOf_Object1,
502
   TR::unknownMethod
503
   };
504

505
bool
506
J9::MethodSymbol::safeToSkipChecksOnArrayCopies()
507
   {
508
   TR::RecognizedMethod methodId = self()->getRecognizedMethod();
509
   if (methodId == TR::unknownMethod)
510
      return false;
511

512
   for (int i = 0; canSkipChecksOnArrayCopies[i] != TR::unknownMethod; ++i)
513
      if (canSkipChecksOnArrayCopies[i] == methodId)
514
         return true;
515

516
   static char *disableExtraCopyOfOpts=feGetEnv("TR_DisableExtraCopyOfOpts");
517
   if (!disableExtraCopyOfOpts)
518
      for (int i = 0; extraCanSkipChecksOnArrayCopies[i] != TR::unknownMethod; ++i)
519
         if (extraCanSkipChecksOnArrayCopies[i] == methodId)
520
            return true;
521

522
   return false;
523
   }
524

525
// Which recognized methods are known to not require zero initialization of arrays
526
//
527
static TR::RecognizedMethod canSkipZeroInitializationOnNewarrays[] =
528
   {
529
   TR::java_lang_Character_toLowerCase,
530
   TR::java_lang_String_init,
531
   TR::java_lang_String_init_int_int_char_boolean,
532
   TR::java_lang_String_concat,
533
   TR::java_lang_String_replace,
534
   TR::java_lang_String_toCharArray,
535
   TR::java_lang_String_toLowerCase,
536
   //TR::java_lang_String_toUpperCase,
537
   TR::java_lang_String_toLowerCaseCore,
538
   //TR::java_lang_String_toUpperCaseCore,
539
   TR::java_lang_String_split_str_int,
540
   TR::java_math_BigDecimal_toString,
541
   TR::java_lang_StringCoding_encode,
542
   TR::java_lang_StringCoding_decode,
543
   TR::java_lang_StringCoding_StringEncoder_encode,
544
   TR::java_lang_StringCoding_StringDecoder_decode,
545
   //TR::java_lang_StringBuilder_ensureCapacityImpl,
546
   //TR::java_lang_StringBuffer_ensureCapacityImpl,
547
   //TR::java_util_Arrays_copyOf,
548
   TR::java_io_Writer_write_lStringII,
549
   TR::java_io_Writer_write_I,
550
   TR::java_util_regex_Matcher_init,
551
   TR::java_util_regex_Matcher_usePattern,
552
   TR::unknownMethod
553
   };
554

555

556
bool
557
J9::MethodSymbol::safeToSkipZeroInitializationOnNewarrays()
558
   {
559
   TR::RecognizedMethod methodId = self()->getRecognizedMethod();
560
   if (methodId == TR::unknownMethod)
561
      return false;
562

563
   for (int i = 0; canSkipZeroInitializationOnNewarrays[i] != TR::unknownMethod; ++i)
564
      if (canSkipZeroInitializationOnNewarrays[i] == methodId)
565
         return true;
566

567
   return false;
568
   }
569

570
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