chore(profiler): Docs on profiler command and more complete error rep…

…orting (#7436)

Co-authored-by: Michael J Klein <[email protected]>

tooling/profiler/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "noir_profiler"
-description = "Profiler for noir circuits"
+description = "Profiler for Noir circuits"
 version.workspace = true
 authors.workspace = true
 edition.workspace = true
@@ -34,6 +34,7 @@ nargo.workspace = true
 noirc_errors.workspace = true
 noirc_abi.workspace = true
 noirc_evaluator.workspace = true
+thiserror.workspace = true
 
 # Logs
 tracing-subscriber.workspace = true

tooling/profiler/src/cli/execution_flamegraph_cmd.rs

@@ -1,18 +1,23 @@
 use std::path::{Path, PathBuf};
 
+use acir::circuit::Opcode;
 use acir::circuit::OpcodeLocation;
 use clap::Args;
 use color_eyre::eyre::{self, Context};
+use nargo::errors::try_to_diagnose_runtime_error;
 use nargo::foreign_calls::DefaultForeignCallBuilder;
 use nargo::PrintOutput;
+use noirc_artifacts::program::ProgramArtifact;
 
+use crate::errors::{report_error, CliError};
 use crate::flamegraph::{BrilligExecutionSample, FlamegraphGenerator, InfernoFlamegraphGenerator};
 use crate::fs::{read_inputs_from_file, read_program_from_file};
 use crate::opcode_formatter::format_brillig_opcode;
 use bn254_blackbox_solver::Bn254BlackBoxSolver;
 use noirc_abi::input_parser::Format;
 use noirc_artifacts::debug::DebugArtifact;
 
+/// Generates a flamegraph mapping unconstrained Noir execution to source code.
 #[derive(Debug, Clone, Args)]
 pub(crate) struct ExecutionFlamegraphCommand {
     /// The path to the artifact JSON file
@@ -54,17 +59,40 @@ fn run_with_generator(
     let program =
         read_program_from_file(artifact_path).context("Error reading program from file")?;
 
+    ensure_brillig_entry_point(&program)?;
+
     let (inputs_map, _) = read_inputs_from_file(prover_toml_path, Format::Toml, &program.abi)?;
 
     let initial_witness = program.abi.encode(&inputs_map, None)?;
 
-    println!("Executing");
-    let (_, mut profiling_samples) = nargo::ops::execute_program_with_profiling(
+    println!("Executing...");
+
+    let solved_witness_stack_err = nargo::ops::execute_program_with_profiling(
         &program.bytecode,
         initial_witness,
         &Bn254BlackBoxSolver(pedantic_solving),
         &mut DefaultForeignCallBuilder::default().with_output(PrintOutput::Stdout).build(),
-    )?;
+    );
+    let mut profiling_samples = match solved_witness_stack_err {
+        Ok((_, profiling_samples)) => profiling_samples,
+        Err(err) => {
+            let debug_artifact = DebugArtifact {
+                debug_symbols: program.debug_symbols.debug_infos.clone(),
+                file_map: program.file_map.clone(),
+            };
+
+            if let Some(diagnostic) = try_to_diagnose_runtime_error(
+                &err,
+                &program.abi,
+                &program.debug_symbols.debug_infos,
+            ) {
+                diagnostic.report(&debug_artifact, false);
+            }
+
+            return Err(CliError::Generic.into());
+        }
+    };
+
     println!("Executed");
 
     println!("Collecting {} samples", profiling_samples.len());
@@ -104,3 +132,22 @@ fn run_with_generator(
 
     Ok(())
 }
+
+fn ensure_brillig_entry_point(artifact: &ProgramArtifact) -> Result<(), CliError> {
+    let err_msg = "Command only supports fully unconstrained Noir programs e.g. `unconstrained fn main() { .. }".to_owned();
+    let program = &artifact.bytecode;
+    if program.functions.len() != 1 || program.unconstrained_functions.len() != 1 {
+        return report_error(err_msg);
+    }
+
+    let main_function = &program.functions[0];
+    let Opcode::BrilligCall { id, .. } = main_function.opcodes[0] else {
+        return report_error(err_msg);
+    };
+
+    if id.as_usize() != 0 {
+        return report_error(err_msg);
+    }
+
+    Ok(())
+}

tooling/profiler/src/cli/gates_flamegraph_cmd.rs

@@ -11,20 +11,22 @@ use crate::fs::read_program_from_file;
 use crate::gates_provider::{BackendGatesProvider, GatesProvider};
 use crate::opcode_formatter::format_acir_opcode;
 
+/// Generates a flamegraph mapping backend opcodes to their associated locations in the source code.
 #[derive(Debug, Clone, Args)]
 pub(crate) struct GatesFlamegraphCommand {
     /// The path to the artifact JSON file
     #[clap(long, short)]
     artifact_path: String,
 
-    /// Path to the noir backend binary
+    /// Path to the Noir backend binary
     #[clap(long, short)]
     backend_path: String,
 
     /// Command to get a gates report from the backend. Defaults to "gates"
     #[clap(long, short = 'g', default_value = "gates")]
     backend_gates_command: String,
 
+    /// Optional arguments for the backend gates command
     #[arg(trailing_var_arg = true, allow_hyphen_values = true)]
     backend_extra_args: Vec<String>,
 

tooling/profiler/src/cli/mod.rs

@@ -32,5 +32,7 @@ pub(crate) fn start_cli() -> eyre::Result<()> {
         ProfilerCommand::Gates(args) => gates_flamegraph_cmd::run(args),
         ProfilerCommand::Opcodes(args) => opcodes_flamegraph_cmd::run(args),
         ProfilerCommand::ExecutionOpcodes(args) => execution_flamegraph_cmd::run(args),
-    }
+    }?;
+
+    Ok(())
 }

tooling/profiler/src/cli/opcodes_flamegraph_cmd.rs

@@ -11,6 +11,7 @@ use crate::flamegraph::{CompilationSample, FlamegraphGenerator, InfernoFlamegrap
 use crate::fs::read_program_from_file;
 use crate::opcode_formatter::{format_acir_opcode, format_brillig_opcode};
 
+/// Generates a flamegraph mapping ACIR opcodes to their associated locations in the source code.
 #[derive(Debug, Clone, Args)]
 pub(crate) struct OpcodesFlamegraphCommand {
     /// The path to the artifact JSON file

tooling/profiler/src/errors.rs

@@ -0,0 +1,16 @@
+use fm::FileMap;
+use noirc_errors::{CustomDiagnostic, Span};
+use thiserror::Error;
+
+#[derive(Debug, Error)]
+pub(crate) enum CliError {
+    #[error("Failed to run profiler command")]
+    Generic,
+}
+
+/// Report an error from the CLI that is not reliant on a stack trace.
+pub(crate) fn report_error(message: String) -> Result<(), CliError> {
+    let error = CustomDiagnostic::simple_error(message.clone(), String::new(), Span::default());
+    noirc_errors::reporter::report(&FileMap::default(), &error, None, false);
+    Err(CliError::Generic)
+}

tooling/profiler/src/main.rs

@@ -4,6 +4,7 @@
 #![cfg_attr(not(test), warn(unused_crate_dependencies, unused_extern_crates))]
 
 mod cli;
+mod errors;
 mod flamegraph;
 mod fs;
 mod gates_provider;
@@ -33,7 +34,7 @@ fn main() {
     }
 
     if let Err(report) = cli::start_cli() {
-        eprintln!("{report:?}");
+        eprintln!("{report}");
         std::process::exit(1);
     }
 }