[Bug]: Typename shadowing causes mix-up

[kevinclancy]

Describe the issue:

When we have a nested struct and a top-level struct with the same name, the nested struct is incorrectly used as the type for parameters that are declared with the top-level struct.

Code example to reproduce the issue:

Run --print slithir on the following code.

pragma solidity 0.8.13;

interface Interface {
    struct ZZZ {
        int x;
        int y;
    }
}

struct ZZZ {
    int x;
    int y;
    int z;
}

contract A {
    function test(ZZZ memory zzz) external {
        zzz.z = 3;

        Interface.ZZZ memory zzz2 = Interface.ZZZ(1,2);
    }
}

Version:

0.9.6

Relevant log output:

Contract A
        Function A.test(Interface.ZZZ) (*)
                Expression: zzz.z = 3
                IRs:
                        REF_0(uint256) -> zzz.z
                        REF_0(uint256) (->zzz) := 3(uint256)
                Expression: zzz2 = Interface.ZZZ(1,2)
                IRs:
                        TMP_0(Interface.ZZZ) = new ZZZ(1,2)
                        zzz2(Interface.ZZZ) := TMP_0(Interface.ZZZ)

Note that above we have Function A.test(Interface.ZZZ) instead of Function A.test(ZZZ)

[0xalpharush]

I think this is related to #1809