36 lines
		
	
	
		
			808 B
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			36 lines
		
	
	
		
			808 B
		
	
	
	
		
			Go
		
	
	
	
	
	
| package vm
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| 
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| import (
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| 	"math/big"
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| 
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| 	"github.com/ethereum/go-ethereum/ethutil"
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| )
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| 
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| func analyseJumpDests(code []byte) (dests map[int64]*big.Int) {
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| 	dests = make(map[int64]*big.Int)
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| 
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| 	lp := false
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| 	var lpv *big.Int
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| 	for pc := int64(0); pc < int64(len(code)); pc++ {
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| 		var op OpCode = OpCode(code[pc])
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| 		switch op {
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| 		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:
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| 			a := int64(op) - int64(PUSH1) + 1
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| 			if int64(len(code)) > pc+1+a {
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| 				lpv = ethutil.BigD(code[pc+1 : pc+1+a])
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| 			}
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| 
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| 			pc += a
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| 			lp = true
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| 		case JUMP, JUMPI:
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| 			if lp {
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| 				dests[pc] = lpv
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| 			}
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| 
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| 		default:
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| 			lp = false
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| 		}
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| 	}
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| 	return
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| }
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