From 468501cb860508af55e1fcd586e1498df0a2d984 Mon Sep 17 00:00:00 2001
From: obscuren <geffobscura@gmail.com>
Date: Wed, 10 Jun 2015 10:44:46 +0200
Subject: [PATCH] core/vm: changed program counter to uint64

---
 core/vm/context.go |  8 ++++----
 core/vm/vm.go      | 18 +++++++++---------
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/core/vm/context.go b/core/vm/context.go
index de03f84f07..e33324b535 100644
--- a/core/vm/context.go
+++ b/core/vm/context.go
@@ -49,13 +49,13 @@ func NewContext(caller ContextRef, object ContextRef, value, gas, price *big.Int
 	return c
 }
 
-func (c *Context) GetOp(n *big.Int) OpCode {
+func (c *Context) GetOp(n uint64) OpCode {
 	return OpCode(c.GetByte(n))
 }
 
-func (c *Context) GetByte(n *big.Int) byte {
-	if n.Cmp(big.NewInt(int64(len(c.Code)))) < 0 {
-		return c.Code[n.Int64()]
+func (c *Context) GetByte(n uint64) byte {
+	if n < uint64(len(c.Code)) {
+		return c.Code[n]
 	}
 
 	return 0
diff --git a/core/vm/vm.go b/core/vm/vm.go
index 2bd950385d..ed4157178d 100644
--- a/core/vm/vm.go
+++ b/core/vm/vm.go
@@ -81,17 +81,17 @@ func (self *Vm) Run(context *Context, callData []byte) (ret []byte, err error) {
 		codehash = crypto.Sha3Hash(code)
 		mem      = NewMemory()
 		stack    = newStack()
-		pc       = new(big.Int)
+		pc       = uint64(0)
 		statedb  = self.env.State()
 
-		jump = func(from *big.Int, to *big.Int) error {
+		jump = func(from uint64, to *big.Int) error {
 			if !context.jumpdests.has(codehash, code, to) {
-				nop := context.GetOp(to)
+				nop := context.GetOp(to.Uint64())
 				return fmt.Errorf("invalid jump destination (%v) %v", nop, to)
 			}
 
 			self.Printf(" ~> %v", to)
-			pc = to
+			pc = to.Uint64()
 
 			self.Endl()
 
@@ -519,11 +519,11 @@ func (self *Vm) Run(context *Context, callData []byte) (ret []byte, err error) {
 			stack.push(self.env.GasLimit())
 
 		case PUSH1, PUSH2, PUSH3, PUSH4, PUSH5, PUSH6, PUSH7, PUSH8, PUSH9, PUSH10, PUSH11, PUSH12, PUSH13, PUSH14, PUSH15, PUSH16, PUSH17, PUSH18, PUSH19, PUSH20, PUSH21, PUSH22, PUSH23, PUSH24, PUSH25, PUSH26, PUSH27, PUSH28, PUSH29, PUSH30, PUSH31, PUSH32:
-			a := big.NewInt(int64(op - PUSH1 + 1))
-			byts := getData(code, new(big.Int).Add(pc, big.NewInt(1)), a)
+			size := uint64(op - PUSH1 + 1)
+			byts := getData(code, new(big.Int).SetUint64(pc+1), new(big.Int).SetUint64(size))
 			// push value to stack
 			stack.push(common.Bytes2Big(byts))
-			pc.Add(pc, a)
+			pc += size
 
 			self.Printf(" => 0x%x", byts)
 		case POP:
@@ -603,7 +603,7 @@ func (self *Vm) Run(context *Context, callData []byte) (ret []byte, err error) {
 
 		case JUMPDEST:
 		case PC:
-			stack.push(pc)
+			stack.push(new(big.Int).SetUint64(pc))
 		case MSIZE:
 			stack.push(big.NewInt(int64(mem.Len())))
 		case GAS:
@@ -708,7 +708,7 @@ func (self *Vm) Run(context *Context, callData []byte) (ret []byte, err error) {
 			return nil, fmt.Errorf("Invalid opcode %x", op)
 		}
 
-		pc.Add(pc, One)
+		pc++
 
 		self.Endl()
 	}