bbc4ea4ae8
The run loop, which previously contained custom opcode executes have been removed and has been simplified to a few checks. Each operation consists of 4 elements: execution function, gas cost function, stack validation function and memory size function. The execution function implements the operation's runtime behaviour, the gas cost function implements the operation gas costs function and greatly depends on the memory and stack, the stack validation function validates the stack and makes sure that enough items can be popped off and pushed on and the memory size function calculates the memory required for the operation and returns it. This commit also allows the EVM to go unmetered. This is helpful for offline operations such as contract calls.
21 lines
418 B
Go
21 lines
418 B
Go
package vm
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import (
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"fmt"
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"github.com/ethereum/go-ethereum/params"
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)
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func makeStackFunc(pop, push int) stackValidationFunc {
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return func(stack *Stack) error {
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if err := stack.require(pop); err != nil {
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return err
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}
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if push > 0 && int64(stack.len()-pop+push) > params.StackLimit.Int64() {
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return fmt.Errorf("stack limit reached %d (%d)", stack.len(), params.StackLimit.Int64())
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}
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return nil
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}
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}
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