all: make timestamp-based fork checks based on uint64 (#26474)

This PR changes the API so that uint64 is used for fork timestamps.
It's a good choice because types.Header also uses uint64 for time.

Co-authored-by: Felix Lange <fjl@twurst.com>

core/vm/evm.go

@@ -71,7 +71,7 @@ type BlockContext struct {
 	Coinbase    common.Address // Provides information for COINBASE
 	GasLimit    uint64         // Provides information for GASLIMIT
 	BlockNumber *big.Int       // Provides information for NUMBER
-	Time        *big.Int       // Provides information for TIME
+	Time        uint64         // Provides information for TIME
 	Difficulty  *big.Int       // Provides information for DIFFICULTY
 	BaseFee     *big.Int       // Provides information for BASEFEE
 	Random      *common.Hash   // Provides information for PREVRANDAO

core/vm/instructions.go

@@ -460,8 +460,7 @@ func opCoinbase(pc *uint64, interpreter *EVMInterpreter, scope *ScopeContext) ([
 }
 
 func opTimestamp(pc *uint64, interpreter *EVMInterpreter, scope *ScopeContext) ([]byte, error) {
-	v, _ := uint256.FromBig(interpreter.evm.Context.Time)
-	scope.Stack.push(v)
+	scope.Stack.push(new(uint256.Int).SetUint64(interpreter.evm.Context.Time))
 	return nil, nil
 }
 

core/vm/runtime/runtime.go

@@ -19,7 +19,6 @@ package runtime
 import (
 	"math"
 	"math/big"
-	"time"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/rawdb"
@@ -37,7 +36,7 @@ type Config struct {
 	Origin      common.Address
 	Coinbase    common.Address
 	BlockNumber *big.Int
-	Time        *big.Int
+	Time        uint64
 	GasLimit    uint64
 	GasPrice    *big.Int
 	Value       *big.Int
@@ -74,9 +73,6 @@ func setDefaults(cfg *Config) {
 	if cfg.Difficulty == nil {
 		cfg.Difficulty = new(big.Int)
 	}
-	if cfg.Time == nil {
-		cfg.Time = big.NewInt(time.Now().Unix())
-	}
 	if cfg.GasLimit == 0 {
 		cfg.GasLimit = math.MaxUint64
 	}

core/vm/runtime/runtime_test.go

@@ -48,9 +48,6 @@ func TestDefaults(t *testing.T) {
 		t.Error("expected difficulty to be non nil")
 	}
 
-	if cfg.Time == nil {
-		t.Error("expected time to be non nil")
-	}
 	if cfg.GasLimit == 0 {
 		t.Error("didn't expect gaslimit to be zero")
 	}
@@ -174,7 +171,7 @@ func benchmarkEVM_Create(bench *testing.B, code string) {
 		State:       statedb,
 		GasLimit:    10000000,
 		Difficulty:  big.NewInt(0x200000),
-		Time:        new(big.Int).SetUint64(0),
+		Time:        0,
 		Coinbase:    common.Address{},
 		BlockNumber: new(big.Int).SetUint64(1),
 		ChainConfig: &params.ChainConfig{