go-ethereum/vm/analysis.go

package vm

import "gopkg.in/fatih/set.v0"

func analyseJumpDests(code []byte) (dests *set.Set) {
	dests = set.New()

	for pc := uint64(0); pc < uint64(len(code)); pc++ {
		var op OpCode = OpCode(code[pc])
		switch op {
		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 := uint64(op) - uint64(PUSH1) + 1

			pc += a
		case JUMPDEST:
			dests.Add(pc)
		}
	}
	return
}