Merge pull request #14981 from karalabe/metropolis-returndata

core/vm: implement RETURNDATA metropolis opcodes

1 files changed, 27 insertions, 1 deletions

diff --git a/core/vm/gas_table.go b/core/vm/gas_table.go
index 8a6c2741d..a6346bd80 100644
--- a/core/vm/gas_table.go
+++ b/core/vm/gas_table.go
@@ -65,7 +65,33 @@ func constGasFunc(gas uint64) gasFunc {
 	}
 }
 
-func gasCalldataCopy(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) {
+func gasCallDataCopy(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) {
+	gas, err := memoryGasCost(mem, memorySize)
+	if err != nil {
+		return 0, err
+	}
+
+	var overflow bool
+	if gas, overflow = math.SafeAdd(gas, GasFastestStep); overflow {
+		return 0, errGasUintOverflow
+	}
+
+	words, overflow := bigUint64(stack.Back(2))
+	if overflow {
+		return 0, errGasUintOverflow
+	}
+
+	if words, overflow = math.SafeMul(toWordSize(words), params.CopyGas); overflow {
+		return 0, errGasUintOverflow
+	}
+
+	if gas, overflow = math.SafeAdd(gas, words); overflow {
+		return 0, errGasUintOverflow
+	}
+	return gas, nil
+}
+
+func gasReturnDataCopy(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) {
 	gas, err := memoryGasCost(mem, memorySize)
 	if err != nil {
 		return 0, err