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Migrate Operand Stack to Growing Stack (#6068)
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To improve the performance of CALL operations move the OperandStack and
ReturnStack to growing stacks instead of a fully allocated stack.

Signed-off-by: Danno Ferrin <danno.ferrin@swirldslabs.com>
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shemnon authored Oct 25, 2023
1 parent af011d2 commit 949c724
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Showing 15 changed files with 360 additions and 45 deletions.
4 changes: 2 additions & 2 deletions evm/src/main/java/org/hyperledger/besu/evm/EVM.java
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import org.hyperledger.besu.evm.gascalculator.GasCalculator;
import org.hyperledger.besu.evm.internal.CodeCache;
import org.hyperledger.besu.evm.internal.EvmConfiguration;
import org.hyperledger.besu.evm.internal.FixedStack.OverflowException;
import org.hyperledger.besu.evm.internal.FixedStack.UnderflowException;
import org.hyperledger.besu.evm.internal.OverflowException;
import org.hyperledger.besu.evm.internal.UnderflowException;
import org.hyperledger.besu.evm.operation.AddModOperation;
import org.hyperledger.besu.evm.operation.AddOperation;
import org.hyperledger.besu.evm.operation.AndOperation;
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import org.hyperledger.besu.datatypes.Wei;
import org.hyperledger.besu.evm.Code;
import org.hyperledger.besu.evm.code.CodeSection;
import org.hyperledger.besu.evm.internal.FixedStack.UnderflowException;
import org.hyperledger.besu.evm.internal.MemoryEntry;
import org.hyperledger.besu.evm.internal.OperandStack;
import org.hyperledger.besu.evm.internal.ReturnStack;
import org.hyperledger.besu.evm.internal.StorageEntry;
import org.hyperledger.besu.evm.internal.UnderflowException;
import org.hyperledger.besu.evm.log.Log;
import org.hyperledger.besu.evm.operation.Operation;
import org.hyperledger.besu.evm.worldstate.WorldUpdater;
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import java.util.Arrays;

/**
* An operand stack for the Ethereum Virtual machine (EVM).
* An operand stack for the Ethereum Virtual machine (EVM). This stack allocates the entire stack at
* initialization time.
*
* <p>The operand stack is responsible for storing the current operands that the EVM can execute. It
* is assumed to have a fixed size.
Expand All @@ -35,30 +36,6 @@ public class FixedStack<T> {

private int top;

/** The Underflow exception. */
public static class UnderflowException extends RuntimeException {
// Don't create a stack trace since these are not "errors" per say but are using exceptions to
// throw rare control flow conditions (EVM stack overflow) that are expected to be seen in
// normal
// operations.
@Override
public synchronized Throwable fillInStackTrace() {
return this;
}
}

/** The Overflow exception. */
public static class OverflowException extends RuntimeException {
// Don't create a stack trace since these are not "errors" per say but are using exceptions to
// throw rare control flow conditions (EVM stack overflow) that are expected to be seen in
// normal
// operations.
@Override
public synchronized Throwable fillInStackTrace() {
return this;
}
}

/**
* Instantiates a new Fixed stack.
*
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253 changes: 253 additions & 0 deletions evm/src/main/java/org/hyperledger/besu/evm/internal/FlexStack.java
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/*
* Copyright contributors to Hyperledger Besu
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
* an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
* specific language governing permissions and limitations under the License.
*
* SPDX-License-Identifier: Apache-2.0
*/
package org.hyperledger.besu.evm.internal;

import static com.google.common.base.Preconditions.checkArgument;

import java.lang.reflect.Array;
import java.util.Arrays;
import java.util.Objects;

/**
* An operand stack for the Ethereum Virtual machine (EVM). The stack grows 32 entries at a time if
* it expands past the top of the allocated stack, up to maxSize.
*
* <p>The operand stack is responsible for storing the current operands that the EVM can execute. It
* is assumed to have a fixed maximum size but may have a smaller memory footprint.
*
* @param <T> the type parameter
*/
public class FlexStack<T> {

private static final int INCREMENT = 32;

private T[] entries;

private final int maxSize;
private int currentCapacity;

private int top;

/**
* Instantiates a new Flex stack.
*
* @param maxSize the max size
* @param klass the klass
*/
@SuppressWarnings("unchecked")
public FlexStack(final int maxSize, final Class<T> klass) {
checkArgument(maxSize > 0, "max size must be positive");

this.currentCapacity = Math.min(INCREMENT, maxSize);
this.entries = (T[]) Array.newInstance(klass, currentCapacity);
this.maxSize = maxSize;
this.top = -1;
}

/**
* Get operand.
*
* @param offset the offset
* @return the operand
*/
public T get(final int offset) {
if (offset < 0 || offset >= size()) {
throw new UnderflowException();
}

return entries[top - offset];
}

/**
* Pop operand.
*
* @return the operand
*/
public T pop() {
if (top < 0) {
throw new UnderflowException();
}

final T removed = entries[top];
entries[top--] = null;
return removed;
}

/**
* Peek and return type T.
*
* @return the T entry
*/
public T peek() {
if (top < 0) {
return null;
} else {
return entries[top];
}
}

/**
* Pops the specified number of operands from the stack.
*
* @param items the number of operands to pop off the stack
* @throws IllegalArgumentException if the items to pop is negative.
* @throws UnderflowException when the items to pop is greater than {@link #size()}
*/
public void bulkPop(final int items) {
checkArgument(items > 0, "number of items to pop must be greater than 0");
if (items > size()) {
throw new UnderflowException();
}

Arrays.fill(entries, top - items + 1, top + 1, null);
top -= items;
}

/**
* Trims the "middle" section of items out of the stack. Items below the cutpoint remains, and of
* the items above only the itemsToKeep items remain. All items in the middle are removed.
*
* @param cutPoint Point at which to start removing items
* @param itemsToKeep itemsToKeep Number of items on top to place at the cutPoint
* @throws IllegalArgumentException if the cutPoint or items to keep is negative.
* @throws UnderflowException If there are less than itemsToKeep above the cutPoint
*/
public void preserveTop(final int cutPoint, final int itemsToKeep) {
checkArgument(cutPoint >= 0, "cutPoint must be positive");
checkArgument(itemsToKeep >= 0, "itemsToKeep must be positive");
if (itemsToKeep == 0) {
if (cutPoint < size()) {
bulkPop(top - cutPoint);
}
} else {
int targetSize = cutPoint + itemsToKeep;
int currentSize = size();
if (targetSize > currentSize) {
throw new UnderflowException();
} else if (targetSize < currentSize) {
System.arraycopy(entries, currentSize - itemsToKeep, entries, cutPoint, itemsToKeep);
Arrays.fill(entries, targetSize, currentSize, null);
top = targetSize - 1;
}
}
}

@SuppressWarnings("unchecked")
private void expandEntries(final int nextSize) {
var nextEntries = (T[]) Array.newInstance(entries.getClass().getComponentType(), nextSize);
System.arraycopy(entries, 0, nextEntries, 0, currentCapacity);
entries = nextEntries;
currentCapacity = nextSize;
}

/**
* Push operand.
*
* @param operand the operand
*/
public void push(final T operand) {
final int nextTop = top + 1;
if (nextTop >= maxSize) {
throw new OverflowException();
}
if (nextTop >= currentCapacity) {
expandEntries(Math.min(currentCapacity + INCREMENT, maxSize));
}
entries[nextTop] = operand;
top = nextTop;
}

/**
* Set operand.
*
* @param offset the offset
* @param operand the operand
*/
public void set(final int offset, final T operand) {
if (offset < 0) {
throw new UnderflowException();
} else if (offset > top) {
throw new OverflowException();
}

entries[top - offset] = operand;
}

/**
* Size of entries.
*
* @return the size
*/
public int size() {
return top + 1;
}

@Override
public String toString() {
final StringBuilder builder = new StringBuilder();
for (int i = 0; i < top; ++i) {
builder.append(String.format("%n0x%04X ", i)).append(entries[i]);
}
return builder.toString();
}

@Override
public int hashCode() {
int result = 1;

for (int i = 0; i < currentCapacity; i++) {
result = 31 * result + (entries[i] == null ? 0 : entries[i].hashCode());
}

return result;
}

@SuppressWarnings("unchecked")
@Override
public boolean equals(final Object other) {
if (!(other instanceof FlexStack)) {
return false;
}

final FlexStack<T> that = (FlexStack<T>) other;
if (this.currentCapacity != that.currentCapacity) {
return false;
}
for (int i = 0; i < currentCapacity; i++) {
if (!Objects.deepEquals(this.entries[i], that.entries[i])) {
return false;
}
}
return true;
}

/**
* Is stack full.
*
* @return the boolean
*/
public boolean isFull() {
return top + 1 >= maxSize;
}

/**
* Is stack empty.
*
* @return the boolean
*/
public boolean isEmpty() {
return top < 0;
}
}
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Expand Up @@ -19,7 +19,7 @@
import org.apache.tuweni.bytes.Bytes;

/** The Operand stack. */
public class OperandStack extends FixedStack<Bytes> {
public class OperandStack extends FlexStack<Bytes> {

/**
* Instantiates a new Operand stack.
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/*
* Copyright contributors to Hyperledger Besu
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
* an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
* specific language governing permissions and limitations under the License.
*
* SPDX-License-Identifier: Apache-2.0
*/
package org.hyperledger.besu.evm.internal;

/**
* Overflow exception for {@link FixedStack} and {@link FlexStack}. The main need for a separate
* class is to remove the stack trace generation as the exception is not used to signal a debuggable
* failure but instead an expected edge case the EVM should handle.
*/
public class OverflowException extends RuntimeException {

/**
* Overload the stack trace fill in so no stack is filled in. This is done for performance reasons
* as this exception signals an expected corner case not a debuggable failure.
*
* @return the exception, with no stack trace filled in.
*/
@Override
public synchronized Throwable fillInStackTrace() {
return this;
}
}
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Expand Up @@ -17,7 +17,7 @@
import java.util.Objects;

/** The type Return stack. */
public class ReturnStack extends FixedStack<ReturnStack.ReturnStackItem> {
public class ReturnStack extends FlexStack<ReturnStack.ReturnStackItem> {

/** The type Return stack item. */
// Java17 convert to record
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