Shanghai Support

[ekpyron]

Tasks

• Add EVM version Shanghai.
• Implement EIP-3855: PUSH0 instruction
  • Add support for the opcode in libevmasm.
  • Change generation of bytecode for pushes with zero-value in Assembly::assemble.
  • Adjust Yul optimizer to rematerialize zero literals. #14225
  • Adjust constant optimizer to take PUSH0 into account. (can be done in a later step after 0.8.20, if need be) (Change the constant optimizer to make use of PUSH0 #14117)
  • Use PUSH0 to replace codegen for "Junk" stack slots in the optimized evm code transform. (Emit PUSH0 as junk in evm code transform, if available. #14133)
• Take EIP-3860: Limit and meter initcode into account. (Add warning for EIP-3860 enforced initcode limits #14127)
• Make Shanghai as the default EVMVersion (Make Shanghai the default EVM version. #14158)
• Testing: evmHost.cpp should populate the access list of coinbase. (Minor)
• Testing: evmhost change latest revision to Shanghai. (Minor)
• Update Docs

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References

• Shanghai Network Upgrade Specification
• Upgrade schedule: Mainnet - 4/12/2023, 10:27:35 PM (UTC)

[ekpyron]

Adjust Yul optimizer to never CSE zeroes.

For the record: this part we can do in a subsequent step - as a matter of fact, as a first step plain support for the Opcode and generating it on a push with zero value in Assembly::assemble is enough for a first PR - the optimizer tweaking we can do later in a secondary step.

[ekpyron]

Changing the milestone to 0.8.21 for the remaining minor improvements in the optimizer.

[hrkrshnn]

I also think we didn't implement this for --opcodes output yet. At least it doesn't seem to give me PUSH0. I'll check this.

[ekpyron]

I also think we didn't implement this for --opcodes output yet. At least it doesn't seem to give me PUSH0. I'll check this.

Should work implicitly (but better to confirm to be sure)

[NunoFilipeSantos]

Shanghai support was released. The rest are optimizations we will eventually get to.