feat(*): use StrictMath for pow(a,b)

actuator/src/main/java/org/tron/core/utils/ProposalUtil.java

@@ -779,6 +779,21 @@ public static void validator(DynamicPropertiesStore dynamicPropertiesStore,
         }
         break;
       }
+      case ALLOW_STRICT_MATH: {
+        if (!forkController.pass(ForkBlockVersionEnum.VERSION_4_8_0)) {
+          throw new ContractValidateException(
+              "Bad chain parameter id [ALLOW_STRICT_MATH]");
+        }
+        if (dynamicPropertiesStore.allowStrictMath()) {
+          throw new ContractValidateException(
+              "[ALLOW_STRICT_MATH] has been valid, no need to propose again");
+        }
+        if (value != 1) {
+          throw new ContractValidateException(
+              "This value[ALLOW_STRICT_MATH] is only allowed to be 1");
+        }
+        break;
+      }
       default:
         break;
     }
@@ -857,7 +872,8 @@ public enum ProposalType {         // current value, value range
     MAX_DELEGATE_LOCK_PERIOD(78), // (86400, 10512000]
     ALLOW_OLD_REWARD_OPT(79), // 0, 1
     ALLOW_ENERGY_ADJUSTMENT(81), // 0, 1
-    MAX_CREATE_ACCOUNT_TX_SIZE(82); // [500, 10000]
+    MAX_CREATE_ACCOUNT_TX_SIZE(82), // [500, 10000]
+    ALLOW_STRICT_MATH(87); // 0, 1
 
     private long code;
 

chainbase/src/main/java/org/tron/common/math/Maths.java

@@ -0,0 +1,30 @@
+package org.tron.common.math;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+import org.tron.core.store.DynamicPropertiesStore;
+
+@Component
+@Slf4j(topic = "math")
+public class Maths {
+
+  private static DynamicPropertiesStore dynamicPropertiesStore;
+
+  @Autowired
+  public Maths(@Autowired DynamicPropertiesStore dynamicPropertiesStore) {
+    Maths.dynamicPropertiesStore = dynamicPropertiesStore;
+  }
+
+  /**
+   * Returns the value of the first argument raised to the power of the second argument.
+   * Note dynamicPropertiesStore must be inited before calling this method.
+   * @param a the base.
+   * @param b the exponent.
+   * @return the value {@code a}<sup>{@code b}</sup>.
+   */
+  public static double pow(double a, double b) {
+    boolean useStrictMath = dynamicPropertiesStore.allowStrictMath();
+    return useStrictMath ? StrictMathWrapper.pow(a, b) : MathWrapper.pow(a, b);
+  }
+}

chainbase/src/main/java/org/tron/core/capsule/ContractStateCapsule.java

@@ -5,6 +5,7 @@
 
 import com.google.protobuf.InvalidProtocolBufferException;
 import lombok.extern.slf4j.Slf4j;
+import org.tron.common.math.Maths;
 import org.tron.core.store.DynamicPropertiesStore;
 import org.tron.protos.contract.SmartContractOuterClass;
 import org.tron.protos.contract.SmartContractOuterClass.ContractState;
@@ -119,7 +120,7 @@ public boolean catchUpToCycle(
     }
 
     // Calc the decrease percent (decrease factor [75% ~ 100%])
-    double decreasePercent = Math.pow(
+    double decreasePercent = Maths.pow(
         1 - (double) increaseFactor / DYNAMIC_ENERGY_DECREASE_DIVISION / precisionFactor,
         cycleCount
     );

chainbase/src/main/java/org/tron/core/capsule/ExchangeProcessor.java

@@ -1,6 +1,7 @@
 package org.tron.core.capsule;
 
 import lombok.extern.slf4j.Slf4j;
+import org.tron.common.math.Maths;
 
 @Slf4j(topic = "capsule")
 public class ExchangeProcessor {
@@ -16,7 +17,7 @@ private long exchangeToSupply(long balance, long quant) {
     long newBalance = balance + quant;
     logger.debug("balance + quant: " + newBalance);
 
-    double issuedSupply = -supply * (1.0 - Math.pow(1.0 + (double) quant / newBalance, 0.0005));
+    double issuedSupply = -supply * (1.0 - Maths.pow(1.0 + (double) quant / newBalance, 0.0005));
     logger.debug("issuedSupply: " + issuedSupply);
     long out = (long) issuedSupply;
     supply += out;
@@ -28,7 +29,7 @@ private long exchangeFromSupply(long balance, long supplyQuant) {
     supply -= supplyQuant;
 
     double exchangeBalance =
-        balance * (Math.pow(1.0 + (double) supplyQuant / supply, 2000.0) - 1.0);
+        balance * (Maths.pow(1.0 + (double) supplyQuant / supply, 2000.0) - 1.0);
     logger.debug("exchangeBalance: " + exchangeBalance);
 
     return (long) exchangeBalance;

chainbase/src/main/java/org/tron/core/store/DynamicPropertiesStore.java

@@ -222,6 +222,7 @@ public class DynamicPropertiesStore extends TronStoreWithRevoking<BytesCapsule>
   private static final byte[] ALLOW_ENERGY_ADJUSTMENT = "ALLOW_ENERGY_ADJUSTMENT".getBytes();
 
   private static final byte[] MAX_CREATE_ACCOUNT_TX_SIZE = "MAX_CREATE_ACCOUNT_TX_SIZE".getBytes();
+  private static final byte[] ALLOW_STRICT_MATH = "ALLOW_STRICT_MATH".getBytes();
 
   @Autowired
   private DynamicPropertiesStore(@Value("properties") String dbName) {
@@ -2876,6 +2877,19 @@ public long getMaxCreateAccountTxSize() {
         .map(ByteArray::toLong)
         .orElse(CommonParameter.getInstance().getMaxCreateAccountTxSize());
   }
+  public long getAllowStrictMath() {
+    return Optional.ofNullable(getUnchecked(ALLOW_STRICT_MATH))
+        .map(BytesCapsule::getData)
+        .map(ByteArray::toLong)
+        .orElse(CommonParameter.getInstance().getAllowStrictMath());
+  }
+  public void saveAllowStrictMath(long allowStrictMath) {
+    this.put(ALLOW_STRICT_MATH, new BytesCapsule(ByteArray.fromLong(allowStrictMath)));
+  }
+
+  public boolean allowStrictMath() {
+    return getAllowStrictMath() == 1L;
+  }
 
   private static class DynamicResourceProperties {
 

common/src/main/java/org/tron/common/math/MathWrapper.java

@@ -0,0 +1,8 @@
+package org.tron.common.math;
+
+public class MathWrapper {
+
+  public static double pow(double a, double b) {
+    return Math.pow(a, b);
+  }
+}

common/src/main/java/org/tron/common/math/StrictMathWrapper.java

@@ -0,0 +1,8 @@
+package org.tron.common.math;
+
+public class StrictMathWrapper {
+
+  public static double pow(double a, double b) {
+    return StrictMath.pow(a, b);
+  }
+}

common/src/main/java/org/tron/common/parameter/CommonParameter.java

@@ -677,6 +677,10 @@ public class CommonParameter {
   @Setter
   public long maxCreateAccountTxSize = 1000L;
 
+  @Getter
+  @Setter
+  public long allowStrictMath;
+
   private static double calcMaxTimeRatio() {
     //return max(2.0, min(5.0, 5 * 4.0 / max(Runtime.getRuntime().availableProcessors(), 1)));
     return 5.0;

common/src/main/java/org/tron/core/Constant.java

@@ -386,4 +386,5 @@ public class Constant {
   public static final String COMMITTEE_ALLOW_OLD_REWARD_OPT = "committee.allowOldRewardOpt";
 
   public static final String COMMITTEE_ALLOW_ENERGY_ADJUSTMENT = "committee.allowEnergyAdjustment";
+  public static final String COMMITTEE_ALLOW_STRICT_MATH = "committee.allowStrictMath";
 }

common/src/main/java/org/tron/core/config/Parameter.java

@@ -24,7 +24,8 @@ public enum ForkBlockVersionEnum {
     VERSION_4_7_1(27, 1596780000000L, 80),
     VERSION_4_7_2(28, 1596780000000L, 80),
     VERSION_4_7_4(29, 1596780000000L, 80),
-    VERSION_4_7_5(30, 1596780000000L, 80);
+    VERSION_4_7_5(30, 1596780000000L, 80),
+    VERSION_4_8_0(31, 1596780000000L, 80);
     // if add a version, modify BLOCK_VERSION simultaneously
 
     @Getter
@@ -73,7 +74,7 @@ public class ChainConstant {
     public static final int SINGLE_REPEAT = 1;
     public static final int BLOCK_FILLED_SLOTS_NUMBER = 128;
     public static final int MAX_FROZEN_NUMBER = 1;
-    public static final int BLOCK_VERSION = 30;
+    public static final int BLOCK_VERSION = 31;
     public static final long FROZEN_PERIOD = 86_400_000L;
     public static final long DELEGATE_PERIOD = 3 * 86_400_000L;
     public static final long TRX_PRECISION = 1000_000L;

framework/src/main/java/org/tron/core/Wallet.java

@@ -1343,6 +1343,11 @@ public Protocol.ChainParameters getChainParameters() {
         .setValue(dbManager.getDynamicPropertiesStore().getMaxCreateAccountTxSize())
         .build());
 
+    builder.addChainParameter(Protocol.ChainParameters.ChainParameter.newBuilder()
+        .setKey("getAllowStrictMath")
+        .setValue(dbManager.getDynamicPropertiesStore().getAllowStrictMath())
+        .build());
+
     return builder.build();
   }
 

framework/src/main/java/org/tron/core/config/args/Args.java

@@ -234,6 +234,7 @@ public static void clearParam() {
     PARAMETER.maxUnsolidifiedBlocks = 54;
     PARAMETER.allowOldRewardOpt = 0;
     PARAMETER.allowEnergyAdjustment = 0;
+    PARAMETER.allowStrictMath = 0;
   }
 
   /**
@@ -1217,6 +1218,10 @@ public static void setParam(final String[] args, final String confFileName) {
             config.hasPath(Constant.COMMITTEE_ALLOW_ENERGY_ADJUSTMENT) ? config
                     .getInt(Constant.COMMITTEE_ALLOW_ENERGY_ADJUSTMENT) : 0;
 
+    PARAMETER.allowStrictMath =
+        config.hasPath(Constant.COMMITTEE_ALLOW_STRICT_MATH) ? config
+            .getInt(Constant.COMMITTEE_ALLOW_STRICT_MATH) : 0;
+
     logConfig();
   }
 

framework/src/main/java/org/tron/core/consensus/ProposalService.java

@@ -367,6 +367,10 @@ public static boolean process(Manager manager, ProposalCapsule proposalCapsule)
           manager.getDynamicPropertiesStore().saveMaxCreateAccountTxSize(entry.getValue());
           break;
         }
+        case ALLOW_STRICT_MATH: {
+          manager.getDynamicPropertiesStore().saveAllowStrictMath(entry.getValue());
+          break;
+        }
         default:
           find = false;
           break;

framework/src/test/java/org/tron/core/capsule/utils/ExchangeProcessorTest.java

@@ -135,5 +135,15 @@ public void testWithdraw() {
 
   }
 
+  @Test
+  public void testStrictMath() {
+    long supply = 1_000_000_000_000_000_000L;
+    ExchangeProcessor processor = new ExchangeProcessor(supply);
+    long anotherTokenQuant = processor.exchange(4732214, 2202692725330L, 29218);
+    chainBaseManager.getDynamicPropertiesStore().saveAllowStrictMath(1);
+    long result = processor.exchange(4732214, 2202692725330L, 29218);
+    Assert.assertNotEquals(anotherTokenQuant, result);
+  }
+
 
 }