the revive-explorer utility (#364)

A maintainable and more precise version of what was a hacky but useful
script, exploring the compilers YUL lowering unit.

It analyzes a given shared objects from the debug dump and outputs:
- The count of each YUL statement translated.
- A per YUL statement break-down of bytecode size contributed per.
- Estimated `yul-phaser` cost parameters.

Signed-off-by: Cyrill Leutwiler <bigcyrill@hotmail.com>

crates/explorer/src/main.rs

@@ -0,0 +1,56 @@
+use std::path::PathBuf;
+
+use clap::Parser;
+
+use revive_explorer::{dwarfdump, dwarfdump_analyzer::DwarfdumpAnalyzer, yul_phaser};
+
+/// The `revive-explorer` is a helper utility for exploring the compilers YUL lowering unit.
+///
+/// It analyzes a given shared objects from the debug dump and outputs:
+/// - The count of each YUL statement translated.
+/// - A per YUL statement break-down of bytecode size contributed per.
+/// - Estimated `yul-phaser` cost parameters.
+#[derive(Parser, Debug)]
+#[command(version, about, long_about = None)]
+struct Args {
+    /// Path of the dwarfdump executable.
+    #[arg(short, long)]
+    dwarfdump: Option<PathBuf>,
+
+    /// The YUL phaser cost scale maximum value.
+    #[arg(short, long, default_value_t = 10)]
+    cost_scale: u64,
+
+    /// Run the provided yul-phaser executable using the estimated costs.
+    #[arg(short, long)]
+    yul_phaser: Option<PathBuf>,
+
+    /// Path of the shared object to analyze.
+    file: PathBuf,
+}
+
+fn main() -> anyhow::Result<()> {
+    let args = Args::parse();
+
+    let source_file = dwarfdump::source_file(&args.file, &args.dwarfdump)?;
+    let debug_lines = dwarfdump::debug_lines(&args.file, &args.dwarfdump)?;
+    let mut analyzer = DwarfdumpAnalyzer::new(source_file.as_path(), debug_lines);
+
+    analyzer.analyze()?;
+
+    if let Some(path) = args.yul_phaser.as_ref() {
+        yul_phaser::run(
+            path,
+            source_file.as_path(),
+            analyzer.phaser_costs(args.cost_scale).as_slice(),
+            num_cpus::get() / 2, // TODO: should be configurable.
+        )?;
+        return Ok(());
+    }
+
+    analyzer.display_statement_count();
+    analyzer.display_statement_size();
+    analyzer.display_phaser_costs(args.cost_scale);
+
+    Ok(())
+}