feat(ssa refactor): experimental-ssa compiler flag (#1289)

* feat(ssa refactor): experimental-ssa compiler flag

* move experimental method into ssa_refactor

* check the experimental flag in the driver module

* undo changes to `create_circuit`

---------

Co-authored-by: Kevaundray Wedderburn <[email protected]>

crates/nargo_cli/src/cli/mod.rs

@@ -85,7 +85,12 @@ pub fn start_cli() -> eyre::Result<()> {
 
 // helper function which tests noir programs by trying to generate a proof and verify it
 pub fn prove_and_verify(proof_name: &str, program_dir: &Path, show_ssa: bool) -> bool {
-    let compile_options = CompileOptions { show_ssa, allow_warnings: false, show_output: false };
+    let compile_options = CompileOptions {
+        show_ssa,
+        allow_warnings: false,
+        show_output: false,
+        experimental_ssa: false,
+    };
     let proof_dir = program_dir.join(PROOFS_DIR);
 
     match prove_cmd::prove_with_path(

crates/noirc_driver/src/lib.rs

@@ -10,7 +10,7 @@ use fm::FileType;
 use iter_extended::try_vecmap;
 use noirc_abi::FunctionSignature;
 use noirc_errors::{reporter, ReportedError};
-use noirc_evaluator::create_circuit;
+use noirc_evaluator::{create_circuit, ssa_refactor::experimental_create_circuit};
 use noirc_frontend::graph::{CrateId, CrateName, CrateType, LOCAL_CRATE};
 use noirc_frontend::hir::def_map::{Contract, CrateDefMap};
 use noirc_frontend::hir::Context;
@@ -43,11 +43,15 @@ pub struct CompileOptions {
     /// Display output of `println` statements
     #[arg(long)]
     pub show_output: bool,
+
+    /// Compile and optimize using the new experimental SSA pass
+    #[arg(long)]
+    pub experimental_ssa: bool,
 }
 
 impl Default for CompileOptions {
     fn default() -> Self {
-        Self { show_ssa: false, allow_warnings: false, show_output: true }
+        Self { show_ssa: false, allow_warnings: false, show_output: true, experimental_ssa: false }
     }
 }
 
@@ -254,13 +258,25 @@ impl Driver {
         let np_language = self.language.clone();
         let is_opcode_supported = acvm::default_is_opcode_supported(np_language.clone());
 
-        match create_circuit(
-            program,
-            np_language,
-            is_opcode_supported,
-            options.show_ssa,
-            options.show_output,
-        ) {
+        let circuit_abi = if options.experimental_ssa {
+            experimental_create_circuit(
+                program,
+                np_language,
+                is_opcode_supported,
+                options.show_ssa,
+                options.show_output,
+            )
+        } else {
+            create_circuit(
+                program,
+                np_language,
+                is_opcode_supported,
+                options.show_ssa,
+                options.show_output,
+            )
+        };
+
+        match circuit_abi {
             Ok((circuit, abi)) => Ok(CompiledProgram { circuit, abi }),
             Err(err) => {
                 // The FileId here will be the file id of the file with the main file

crates/noirc_evaluator/src/ssa_refactor.rs

@@ -7,6 +7,10 @@
 //! This module heavily borrows from Cranelift
 #![allow(dead_code)]
 
+use crate::errors::RuntimeError;
+use acvm::{acir::circuit::Circuit, compiler::transformers::IsOpcodeSupported, Language};
+use noirc_abi::Abi;
+
 use noirc_frontend::monomorphization::ast::Program;
 
 use self::acir_gen::Acir;
@@ -22,3 +26,15 @@ pub mod ssa_gen;
 pub fn optimize_into_acir(program: Program) -> Acir {
     ssa_gen::generate_ssa(program).into_acir()
 }
+/// Compiles the Program into ACIR and applies optimizations to the arithmetic gates
+/// This is analogous to `ssa:create_circuit` and this method is called when one wants
+/// to use the new ssa module to process Noir code.
+pub fn experimental_create_circuit(
+    _program: Program,
+    _np_language: Language,
+    _is_opcode_supported: IsOpcodeSupported,
+    _enable_logging: bool,
+    _show_output: bool,
+) -> Result<(Circuit, Abi), RuntimeError> {
+    todo!("this is a stub function for the new SSA refactor module")
+}