Remove disable_incr_cache from BackendConfig

src/config.rs

@@ -1,10 +1,5 @@
-use std::env;
 use std::str::FromStr;
 
-fn bool_env_var(key: &str) -> bool {
-    env::var(key).as_deref() == Ok("1")
-}
-
 /// The mode to use for compilation.
 #[derive(Copy, Clone, Debug)]
 pub enum CodegenMode {
@@ -41,14 +36,6 @@ pub struct BackendConfig {
     ///
     /// Defaults to the value of `CG_CLIF_JIT_ARGS`.
     pub jit_args: Vec<String>,
-
-    /// 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 {
@@ -64,7 +51,6 @@ impl Default for BackendConfig {
                     }
                 }
             },
-            disable_incr_cache: bool_env_var("CG_CLIF_DISABLE_INCR_CACHE"),
         }
     }
 }
@@ -72,10 +58,6 @@ impl Default for BackendConfig {
 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 opt.starts_with("-import-instr-limit") {
@@ -86,7 +68,6 @@ impl BackendConfig {
             if let Some((name, value)) = opt.split_once('=') {
                 match name {
                     "mode" => config.codegen_mode = value.parse()?,
-                    "disable_incr_cache" => config.disable_incr_cache = parse_bool(name, value)?,
                     _ => return Err(format!("Unknown option `{}`", name)),
                 }
             } else {

src/driver/aot.rs

@@ -1,6 +1,7 @@
 //! The AOT driver uses [`cranelift_object`] to write object files suitable for linking into a
 //! standalone executable.
 
+use std::env;
 use std::fs::{self, File};
 use std::io::BufWriter;
 use std::path::{Path, PathBuf};
@@ -25,13 +26,16 @@ use rustc_middle::mir::mono::{CodegenUnit, MonoItem};
 use rustc_session::Session;
 use rustc_session::config::{DebugInfo, OutFileName, OutputFilenames, OutputType};
 
-use crate::BackendConfig;
 use crate::concurrency_limiter::{ConcurrencyLimiter, ConcurrencyLimiterToken};
 use crate::debuginfo::TypeDebugContext;
 use crate::global_asm::GlobalAsmConfig;
 use crate::prelude::*;
 use crate::unwind_module::UnwindModule;
 
+fn disable_incr_cache() -> bool {
+    env::var("CG_CLIF_DISABLE_INCR_CACHE").as_deref() == Ok("1")
+}
+
 struct ModuleCodegenResult {
     module_regular: CompiledModule,
     module_global_asm: Option<CompiledModule>,
@@ -63,10 +67,10 @@ impl OngoingCodegen {
         self,
         sess: &Session,
         outputs: &OutputFilenames,
-        backend_config: &BackendConfig,
     ) -> (CodegenResults, FxIndexMap<WorkProductId, WorkProduct>) {
         let mut work_products = FxIndexMap::default();
         let mut modules = vec![];
+        let disable_incr_cache = disable_incr_cache();
 
         for module_codegen in self.modules {
             let module_codegen_result = match module_codegen {
@@ -87,7 +91,7 @@ impl OngoingCodegen {
             if let Some((work_product_id, work_product)) = existing_work_product {
                 work_products.insert(work_product_id, work_product);
             } else {
-                let work_product = if backend_config.disable_incr_cache {
+                let work_product = if disable_incr_cache {
                     None
                 } else if let Some(module_global_asm) = &module_global_asm {
                     rustc_incremental::copy_cgu_workproduct_to_incr_comp_cache_dir(
@@ -580,7 +584,6 @@ fn module_codegen(
 
 pub(crate) fn run_aot(
     tcx: TyCtxt<'_>,
-    backend_config: BackendConfig,
     metadata: EncodedMetadata,
     need_metadata_module: bool,
 ) -> Box<OngoingCodegen> {
@@ -626,9 +629,10 @@ pub(crate) fn run_aot(
 
     let global_asm_config = Arc::new(crate::global_asm::GlobalAsmConfig::new(tcx));
 
+    let disable_incr_cache = disable_incr_cache();
     let (todo_cgus, done_cgus) =
         cgus.into_iter().enumerate().partition::<Vec<_>, _>(|&(i, _)| match cgu_reuse[i] {
-            _ if backend_config.disable_incr_cache => true,
+            _ if disable_incr_cache => true,
             CguReuse::No => true,
             CguReuse::PreLto | CguReuse::PostLto => false,
         });

src/lib.rs

@@ -223,7 +223,7 @@ impl CodegenBackend for CraneliftCodegenBackend {
         tcx.dcx().abort_if_errors();
         let config = self.config.borrow().clone().unwrap();
         match config.codegen_mode {
-            CodegenMode::Aot => driver::aot::run_aot(tcx, config, metadata, need_metadata_module),
+            CodegenMode::Aot => driver::aot::run_aot(tcx, metadata, need_metadata_module),
             CodegenMode::Jit | CodegenMode::JitLazy => {
                 #[cfg(feature = "jit")]
                 driver::jit::run_jit(tcx, config);
@@ -242,11 +242,7 @@ impl CodegenBackend for CraneliftCodegenBackend {
     ) -> (CodegenResults, FxIndexMap<WorkProductId, WorkProduct>) {
         let _timer = sess.timer("finish_ongoing_codegen");
 
-        ongoing_codegen.downcast::<driver::aot::OngoingCodegen>().unwrap().join(
-            sess,
-            outputs,
-            self.config.borrow().as_ref().unwrap(),
-        )
+        ongoing_codegen.downcast::<driver::aot::OngoingCodegen>().unwrap().join(sess, outputs)
     }
 }