enable the ability to toggle off the underconstrained check

compiler/noirc_driver/src/lib.rs

@@ -123,6 +123,12 @@ pub struct CompileOptions {
     /// Temporary flag to enable the experimental arithmetic generics feature
     #[arg(long, hide = true)]
     pub arithmetic_generics: bool,
+
+    /// Flag to turn off the compiler check for under constrained values.
+    /// Warning: This can improve compilation speed but can also lead to correctness errors.
+    /// This check should always be run on production code. 
+    #[arg(long)]
+    pub skip_underconstrained_check: bool,
 }
 
 pub fn parse_expression_width(input: &str) -> Result<ExpressionWidth, std::io::Error> {
@@ -576,6 +582,7 @@ pub fn compile_no_check(
             ExpressionWidth::default()
         },
         emit_ssa: if options.emit_ssa { Some(context.package_build_path.clone()) } else { None },
+        skip_underconstrained_check: options.skip_underconstrained_check,
     };
 
     let SsaProgramArtifact { program, debug, warnings, names, error_types, .. } =

compiler/noirc_evaluator/src/ssa.rs

@@ -64,6 +64,9 @@ pub struct SsaEvaluatorOptions {
 
     /// Dump the unoptimized SSA to the supplied path if it exists
     pub emit_ssa: Option<PathBuf>,
+
+    /// Skip the check for under constrained values
+    pub skip_underconstrained_check: bool,
 }
 
 pub(crate) struct ArtifactsAndWarnings(Artifacts, Vec<SsaReport>);
@@ -117,7 +120,11 @@ pub(crate) fn optimize_into_acir(
     .run_pass(Ssa::array_set_optimization, "After Array Set Optimizations:")
     .finish();
 
-    let ssa_level_warnings = ssa.check_for_underconstrained_values();
+    let ssa_level_warnings = if options.skip_underconstrained_check {
+        vec![]
+    } else {
+        time("After Check for Underconstrained Values", options.print_codegen_timings, || ssa.check_for_underconstrained_values())
+    };
     let brillig = time("SSA to Brillig", options.print_codegen_timings, || {
         ssa.to_brillig(options.enable_brillig_logging)
     });

cspell.json

@@ -204,6 +204,7 @@
         "typevar",
         "typevars",
         "udiv",
+        "underconstrained",
         "uninstantiated",
         "unnormalized",
         "unoptimized",