37 lines
849 B
Go
37 lines
849 B
Go
package vm
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import (
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"math/big"
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"gopkg.in/fatih/set.v0"
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)
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type destinations struct {
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set *set.Set
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}
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func (d *destinations) Has(dest *big.Int) bool {
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return d.set.Has(string(dest.Bytes()))
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}
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func (d *destinations) Add(dest *big.Int) {
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d.set.Add(string(dest.Bytes()))
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}
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func analyseJumpDests(code []byte) (dests *destinations) {
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dests = &destinations{set.New()}
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for pc := uint64(0); pc < uint64(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 := uint64(op) - uint64(PUSH1) + 1
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pc += a
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case JUMPDEST:
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dests.Add(big.NewInt(int64(pc)))
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}
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}
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return
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}
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