+use std::env;
use std::str::FromStr;
+fn bool_env_var(key: &str) -> bool {
+ env::var(key).as_ref().map(|val| &**val) == Ok("1")
+}
+
+/// The mode to use for compilation.
#[derive(Copy, Clone, Debug)]
pub enum CodegenMode {
+ /// AOT compile the crate. This is the default.
Aot,
+ /// JIT compile and execute the crate.
Jit,
+ /// JIT compile and execute the crate, but only compile functions the first time they are used.
JitLazy,
}
-impl Default for CodegenMode {
- fn default() -> Self {
- CodegenMode::Aot
- }
-}
-
impl FromStr for CodegenMode {
type Err = String;
}
}
-#[derive(Copy, Clone, Debug, Default)]
+/// Configuration of cg_clif as passed in through `-Cllvm-args` and various env vars.
+#[derive(Clone, Debug)]
pub struct BackendConfig {
+ /// Should the crate be AOT compiled or JIT executed.
+ ///
+ /// Defaults to AOT compilation. Can be set using `-Cllvm-args=mode=...`.
pub codegen_mode: CodegenMode,
+
+ /// When JIT mode is enable pass these arguments to the program.
+ ///
+ /// Defaults to the value of `CG_CLIF_JIT_ARGS`.
+ pub jit_args: Vec<String>,
+
+ /// Display the time it took to perform codegen for a crate.
+ ///
+ /// Defaults to true when the `CG_CLIF_DISPLAY_CG_TIME` env var is set to 1 or false otherwise.
+ /// Can be set using `-Cllvm-args=display_cg_time=...`.
+ pub display_cg_time: bool,
+
+ /// Enable the Cranelift ir verifier for all compilation passes. If not set it will only run
+ /// once before passing the clif ir to Cranelift for compilation.
+ ///
+ /// Defaults to true when the `CG_CLIF_ENABLE_VERIFIER` env var is set to 1 or when cg_clif is
+ /// compiled with debug assertions enabled or false otherwise. Can be set using
+ /// `-Cllvm-args=enable_verifier=...`.
+ pub enable_verifier: bool,
+
+ /// Don't cache object files in the incremental cache. Useful during development of cg_clif
+ /// to make it possible to use incremental mode for all analyses performed by rustc without
+ /// caching object files when their content should have been changed by a change to cg_clif.
+ ///
+ /// Defaults to true when the `CG_CLIF_DISABLE_INCR_CACHE` env var is set to 1 or false
+ /// otherwise. Can be set using `-Cllvm-args=disable_incr_cache=...`.
+ pub disable_incr_cache: bool,
+}
+
+impl Default for BackendConfig {
+ fn default() -> Self {
+ BackendConfig {
+ codegen_mode: CodegenMode::Aot,
+ jit_args: {
+ let args = std::env::var("CG_CLIF_JIT_ARGS").unwrap_or_else(|_| String::new());
+ args.split(' ').map(|arg| arg.to_string()).collect()
+ },
+ display_cg_time: bool_env_var("CG_CLIF_DISPLAY_CG_TIME"),
+ enable_verifier: cfg!(debug_assertions) || bool_env_var("CG_CLIF_ENABLE_VERIFIER"),
+ disable_incr_cache: bool_env_var("CG_CLIF_DISABLE_INCR_CACHE"),
+ }
+ }
}
impl BackendConfig {
+ /// Parse the configuration passed in using `-Cllvm-args`.
pub fn from_opts(opts: &[String]) -> Result<Self, String> {
+ fn parse_bool(name: &str, value: &str) -> Result<bool, String> {
+ value.parse().map_err(|_| format!("failed to parse value `{}` for {}", value, name))
+ }
+
let mut config = BackendConfig::default();
for opt in opts {
if let Some((name, value)) = opt.split_once('=') {
match name {
"mode" => config.codegen_mode = value.parse()?,
+ "display_cg_time" => config.display_cg_time = parse_bool(name, value)?,
+ "enable_verifier" => config.enable_verifier = parse_bool(name, value)?,
+ "disable_incr_cache" => config.disable_incr_cache = parse_bool(name, value)?,
_ => return Err(format!("Unknown option `{}`", name)),
}
} else {
return Err(format!("Invalid option `{}`", opt));
}
}
+
Ok(config)
}
}