refactor: initialize EnzymeWrapper in LlvmCodegenBackend::init

Author: sgasho

compiler/rustc_codegen_llvm/src/back/lto.rs

@@ -529,11 +529,8 @@ fn thin_lto(
 }
 
 #[cfg(feature = "llvm_enzyme")]
-pub(crate) fn enable_autodiff_settings(
-    sysroot: &rustc_session::config::Sysroot,
-    ad: &[config::AutoDiff],
-) {
-    let mut enzyme = llvm::EnzymeWrapper::get_or_init(sysroot);
+pub(crate) fn enable_autodiff_settings(ad: &[config::AutoDiff]) {
+    let mut enzyme = llvm::EnzymeWrapper::get_instance();
 
     for val in ad {
         // We intentionally don't use a wildcard, to not forget handling anything new.

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -731,7 +731,7 @@ pub(crate) unsafe fn llvm_optimize(
     let llvm_plugins = config.llvm_plugins.join(",");
 
     let enzyme_fn = if consider_ad {
-        let wrapper = llvm::EnzymeWrapper::get_or_init(&cgcx.sysroot);
+        let wrapper = llvm::EnzymeWrapper::get_instance();
         wrapper.registerEnzymeAndPassPipeline
     } else {
         std::ptr::null()

compiler/rustc_codegen_llvm/src/lib.rs

@@ -244,12 +244,11 @@ impl CodegenBackend for LlvmCodegenBackend {
         #[cfg(feature = "llvm_enzyme")]
         {
             use rustc_session::config::AutoDiff;
-            if sess.opts.unstable_opts.autodiff.contains(&AutoDiff::Enable) {
-                {
-                    use crate::back::lto::enable_autodiff_settings;
 
-                    enable_autodiff_settings(&sess.opts.sysroot, &sess.opts.unstable_opts.autodiff);
-                }
+            use crate::back::lto::enable_autodiff_settings;
+            if sess.opts.unstable_opts.autodiff.contains(&AutoDiff::Enable) {
+                drop(llvm::EnzymeWrapper::get_or_init(&sess.opts.sysroot));
+                enable_autodiff_settings(&sess.opts.unstable_opts.autodiff);
             }
         }
     }

compiler/rustc_codegen_ssa/src/back/write.rs

@@ -29,7 +29,6 @@ use rustc_middle::ty::TyCtxt;
 use rustc_session::Session;
 use rustc_session::config::{
     self, CrateType, Lto, OutFileName, OutputFilenames, OutputType, Passes, SwitchWithOptPath,
-    Sysroot,
 };
 use rustc_span::source_map::SourceMap;
 use rustc_span::{FileName, InnerSpan, Span, SpanData, sym};
@@ -347,7 +346,6 @@ pub struct CodegenContext<B: WriteBackendMethods> {
     pub split_debuginfo: rustc_target::spec::SplitDebuginfo,
     pub split_dwarf_kind: rustc_session::config::SplitDwarfKind,
     pub pointer_size: Size,
-    pub sysroot: Sysroot,
 
     /// Emitter to use for diagnostics produced during codegen.
     pub diag_emitter: SharedEmitter,
@@ -1319,7 +1317,6 @@ fn start_executing_work<B: ExtraBackendMethods>(
         parallel: backend.supports_parallel() && !sess.opts.unstable_opts.no_parallel_backend,
         pointer_size: tcx.data_layout.pointer_size(),
         invocation_temp: sess.invocation_temp.clone(),
-        sysroot: sess.opts.sysroot.clone(),
     };
 
     // This is the "main loop" of parallel work happening for parallel codegen.