feat(slang): inline assembly

[abinavpp]

Lowers assembly { .. } in the Slang frontend to a sol.inline_asm region of Yul-dialect ops, mirroring the C++ frontend: every inline-assembly-legal Yul builtin, Yul functions, control flow, and Solidity local/state/calldata references through the sol.yul_* bridge ops. Yul call arguments are evaluated right to left as the spec requires, which the C++ frontend does not yet do.

cargo run-tester-slang: 5476 -> 11580 passed, 4 -> 6 failed, 1740 -> 1607 invalid (both new failures explained in the thread).

[Copilot]

Pull request overview

Adds Slang-frontend support for Solidity inline assembly { ... } by lowering it into a sol.inline_asm region containing Yul-dialect MLIR ops, plus the required Yul IR wrappers/bridge ops in solx-mlir and lit coverage to validate parity (and the intended arg-evaluation order differences vs solc).

Changes:

• Implement inline-assembly lowering in solx-slang with an AssemblyScope that tracks Yul variables/functions and leave return slots.
• Introduce Yul dialect IR wrappers (Word, Slot, YulBlock, YulFunction, predicates, references) and Sol↔Yul bridge ops/macros in solx-mlir.
• Add lit tests covering Yul builtins, declarations, control flow, scoping, external references, and evaluation order.

Reviewed changes

Copilot reviewed 28 out of 28 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
solx-slang/src/scope/mod.rs	Adds assembly scope module export and updates scope docs.
solx-slang/src/scope/assembly.rs	Introduces AssemblyScope to manage Yul bindings and region emission.
solx-slang/src/contract/function/statement/mod.rs	Routes AssemblyStatement lowering instead of unimplemented!().
solx-slang/src/contract/function/mod.rs	Exposes new inline-assembly lowering module.
solx-slang/src/contract/function/assembly/mod.rs	Lowers assembly {} to sol.inline_asm, declares/defines Yul functions.
solx-slang/src/contract/function/assembly/statement.rs	Lowers Yul statements and control-flow constructs.
solx-slang/src/contract/function/assembly/reference.rs	Resolves Yul paths to Yul vars or bridged Solidity refs (sol.yul_*).
solx-slang/src/contract/function/assembly/expression.rs	Lowers Yul expressions and builtin/Yul-function calls (RTL arg eval).
solx-mlir/tests/lit/assembly.sol	Lit coverage for a broad set of Yul builtins + memory-safe attribute.
solx-mlir/tests/lit/assembly_function_scopes.sol	Tests sibling function-name reuse + leave in for-init behavior (solx-only).
solx-mlir/tests/lit/assembly_external_references.sol	Tests bridging of locals/state vars/storage/calldata/function ptrs/constants.
solx-mlir/tests/lit/assembly_evaluation_order.sol	Asserts solx vs solc arg evaluation order differences.
solx-mlir/tests/lit/assembly_declarations.sol	Tests let defaults/materialization ordering and tuple assignment.
solx-mlir/tests/lit/assembly_control_flow.sol	Tests Yul if/for/switch/break/continue/functions/forward refs.
solx-mlir/src/macros.rs	Generalizes op-wrapper macro to dialect_ops! and adds Yul kinds/support.
solx-mlir/src/lib.rs	Exports Yul IR wrapper types publicly.
solx-mlir/src/ir/yul/word.rs	Adds Word wrapper for Yul i256 SSA values.
solx-mlir/src/ir/yul/slot.rs	Adds Slot wrapper for !yul.ptr.
solx-mlir/src/ir/yul/reference.rs	Adds YulReference abstraction (slot vs compile-time word).
solx-mlir/src/ir/yul/predicate.rs	Defines YulCmpPredicate attribute enum for yul.cmp.
solx-mlir/src/ir/yul/mod.rs	Declares Yul op-wrapper surface via dialect_ops! (builtins, load/store, calls).
solx-mlir/src/ir/yul/function.rs	Adds YulFunction emitter for yul.func and entry block creation.
solx-mlir/src/ir/yul/block.rs	Adds YulBlock helpers for Yul control-flow ops and terminators.
solx-mlir/src/ir/type/mod.rs	Introduces Type::yul_word and Type::yul_pointer.
solx-mlir/src/ir/mod.rs	Adds sol.inline_asm builder + Sol↔Yul bridge ops (sol.yul_*).
solx-mlir/src/ir/attributes.rs	Renames predicate macro usage to shared predicate_attribute!.
solx-mlir/src/ffi.rs	Adds FFI for constructing !yul.ptr type.
solx-mlir/sol_attr_stubs.cpp	Implements solxCreateYulPtrType via Yul dialect C++ API.

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[github-actions]

Coverage Summary

Crate	Line Coverage	Function Coverage
solx	🟢 83.6%	🔴 20.0%
solx-benchmark-converter	🔴 0.0%	🔴 0.0%
solx-codegen-evm	🔴 25.5%	🔴 13.5%
solx-compiler-downloader	🔴 0.0%	🔴 0.0%
solx-core	🔴 38.6%	🔴 47.4%
solx-dev	🔴 2.4%	🔴 3.0%
solx-evm-assembly	🔴 0.0%	🔴 0.0%
solx-mlir	🔴 49.4%	🔴 44.0%
solx-slang	🔴 20.1%	🔴 28.7%
solx-solc-test-adapter	🔴 1.7%	🔴 2.1%
solx-standard-json	🔴 42.8%	🔴 47.7%
solx-tester	🔴 36.5%	🔴 34.3%
solx-utils	🔴 29.3%	🔴 32.9%
solx-yul	🔴 0.0%	🔴 0.0%
Total	🔴 10.9%	🔴 13.1%

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[Copilot]

Pull request overview

Copilot reviewed 31 out of 31 changed files in this pull request and generated no new comments.

Suppressed comments (2)

solx-slang/src/contract/function/assembly/expression.rs:67

• yul_call builds an intermediate expressions Vec just to reverse-iterate it. You can iterate node.arguments() in reverse directly to avoid the extra allocation and traversal while keeping the required right-to-left evaluation order.

        let expressions: Vec<_> = node.arguments().iter().collect();
        let mut arguments: Vec<_> = expressions
            .iter()
            .rev()
            .map(|argument| self.yul_expression(argument))
            .collect();
        arguments.reverse();

solx-slang/src/contract/function/assembly/reference.rs:87

• This clones the state-variable symbol name on every reference (.name.clone()). Since the value is only needed as &str for building the IR op, you can borrow it directly and avoid the allocation.

                    .storage_layout
                    .get(&state_variable.node_id())
                    .expect("state variable is registered in the storage layout")
                    .name
                    .clone();

[abinavpp]

cargo run-tester-slang, origin/main-slang (6387d7e) vs this branch, same slot, both at the pinned solx-llvm/solx-solidity:

	main-slang	this PR
passed	5472	11576
failed	8	10
invalid	1740	1607

The two new failures are yul_instructions/calldatasize's one_deploy and zero_deploy, INVALID on the base (the file did not compile) and now failing on main.sol:19, which hardcodes 132 bytes of Deploy creation code - this branch emits 144, so at len 0 and 1 the CREATE gets truncated init code. The other cases of that file copy enough and pass.

The remaining 8 failures are identical on both sides: 4 function_modifier.sol cases (no modifiers in solx yet) and 4 standard_functions_high_order.sol cases.

cargo test-slang 201 passed, lit 133/133.

[abinavpp]

@hedgar2017 the two new failures in the tally above are yul_instructions/calldatasize's zero_deploy and one_deploy. The file was INVALID before this PR - nothing here supported inline assembly - so this is the first time it has run.

main.sol hardcodes Deploy's creation-code length (add(132, len)); this branch emits 144 bytes, so those two cases copy truncated init code and the CREATE reverts. Taking the real length fixes them, with a clamp because the largest case would otherwise cross the EIP-3860 init-code limit:

let size := add(mload(deploy_calldata), len)
if gt(size, 49152) { size := 49152 }
let result := create(0, add(deploy_calldata, 32), size)

With that, every case in the file passes locally. What do you think?