fix: some yul commands cause compile error (iszero, eq, etc)

[Taewa]

forge test throw an error due to the some of yul functions such as iszero or eq, etc.

I will leave here an example code in order to reproduce the issue.

// yul contract
object "CompileTest" {
    code {
        datacopy(0, dataoffset("Runtime"), datasize("Runtime"))
        return(0, datasize("Runtime"))
    }

    object "Runtime" {
        code {
            function lte(a, b) -> r {
                r := iszero(gt(a, b))
            }

            function returnUint(v) {
                mstore(0, v)
                return(0, 0x20)
            }
        }
    }
}

and test code

// CompileTest.t.sol
pragma solidity 0.8.15;

import "forge-std/Test.sol";
import "./lib/YulDeployer.sol"; 

interface CompileTest {}

contract CompileTestTest is Test {
    YulDeployer yulDeployer = new YulDeployer();

    CompileTest compileTestContract;

    function setUp() public {
        compileTestContract = CompileTest(yulDeployer.deployContract("CompileTest"));
    }

    function testExample() public {
        // Don't do anything
    }
}

the error:

stderr err="Error: Function "iszero" not found.
  --> yul/CompileTest.yul:10:22:
   |
10 |                 r := iszero(gt(a, b))
   |                      ^^^^^^

Error: Variable count for assignment to "r" does not match number of values (1 vs. 0)
  --> yul/CompileTest.yul:10:17:
   |
10 |                 r := iszero(gt(a, b))
   |                 ^^^^^^^^^^^^^^^^^^^^^

Error: 
u{1b}[31mInvalid datau{1b}[0m
"
2023-02-25T06:33:11.819759Z ERROR forge::runner: setUp failed reason="EvmError: Revert" contract=0x7fa9385be102ac3eac297483dd6233d62b3e1496

[yellowBirdy]

Would be good to merge it , had the same issue

[Taewa]

Would be good to merge it , had the same issue

In order to merge it, I need maintainer's approval, right?

@CodeForcer @flyq

[flyq]

  --yul                Switch to Yul mode, ignoring all options except
                       --machine, --yul-dialect, --optimize and
                       --yul-optimizations and assumes input is Yul.
  --strict-assembly    Switch to strict assembly mode, ignoring all options
                       except --machine, --yul-dialect, --optimize and
                       --yul-optimizations and assumes input is strict
                       assembly.

is the error caused by iszero is a strict assembly, not Yul?

[Taewa]

  --yul                Switch to Yul mode, ignoring all options except
                       --machine, --yul-dialect, --optimize and
                       --yul-optimizations and assumes input is Yul.
  --strict-assembly    Switch to strict assembly mode, ignoring all options
                       except --machine, --yul-dialect, --optimize and
                       --yul-optimizations and assumes input is strict
                       assembly.

is the error caused by iszero is a strict assembly, not Yul?

Yes I experienced the error I mentioned above with --yul. I fixes the error when I use --strict-assembly.

[Taewa]

@flyq thanks for the approval. Do I have right to merge or someone else should merge it?