Remove explicit EmitThinLTOSummary argument

In favor of passing a NULL ThinLTOSummaryBufferRef. And improve type
improve type safety on the Rust side.

compiler/rustc_codegen_llvm/src/back/lto.rs

@@ -2,7 +2,6 @@
 use std::ffi::{CStr, CString};
 use std::fs::File;
 use std::path::{Path, PathBuf};
-use std::ptr::NonNull;
 use std::sync::Arc;
 use std::{io, iter, slice};
 
@@ -660,17 +659,13 @@ pub(crate) fn run_pass_manager(
     debug!("lto done");
 }
 
+#[repr(transparent)]
 pub(crate) struct Buffer(&'static mut llvm::Buffer);
 
 unsafe impl Send for Buffer {}
 unsafe impl Sync for Buffer {}
 
 impl Buffer {
-    pub(crate) unsafe fn from_raw_ptr(ptr: *mut llvm::Buffer) -> Buffer {
-        let mut ptr = NonNull::new(ptr).unwrap();
-        Buffer(unsafe { ptr.as_mut() })
-    }
-
     pub(crate) fn data(&self) -> &[u8] {
         unsafe {
             let ptr = llvm::LLVMRustBufferPtr(self.0);

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -1,7 +1,6 @@
 use std::ffi::{CStr, CString};
 use std::io::{self, Write};
 use std::path::{Path, PathBuf};
-use std::ptr::null_mut;
 use std::sync::Arc;
 use std::{fs, slice, str};
 
@@ -29,7 +28,7 @@
 };
 use tracing::{debug, trace};
 
-use crate::back::lto::ModuleBuffer;
+use crate::back::lto::{Buffer, ModuleBuffer};
 use crate::back::owned_target_machine::OwnedTargetMachine;
 use crate::back::profiling::{
     LlvmSelfProfiler, selfprofile_after_pass_callback, selfprofile_before_pass_callback,
@@ -563,8 +562,8 @@ pub(crate) unsafe fn llvm_optimize(
     prof: &SelfProfilerRef,
     dcx: DiagCtxtHandle<'_>,
     module: &ModuleCodegen<ModuleLlvm>,
-    thin_lto_buffer: Option<&mut *mut llvm::Buffer>,
-    thin_lto_summary_buffer: Option<&mut *mut llvm::Buffer>,
+    thin_lto_buffer: Option<&mut Option<Buffer>>,
+    thin_lto_summary_buffer: Option<&mut Option<Buffer>>,
     config: &ModuleConfig,
     opt_level: config::OptLevel,
     opt_stage: llvm::OptStage,
@@ -788,7 +787,6 @@ fn handle_offload<'ll>(cx: &'ll SimpleCx<'_>, old_fn: &llvm::Value) {
             config.lint_llvm_ir,
             thin_lto_buffer,
             thin_lto_summary_buffer,
-            config.emit_thin_lto_summary,
             merge_functions,
             unroll_loops,
             vectorize_slp,
@@ -939,7 +937,7 @@ pub(crate) fn optimize(
             && config.emit_obj == EmitObj::ObjectCode(BitcodeSection::Full))
             || config.emit_thin_lto_summary
         {
-            (Some(null_mut()), Some(null_mut()))
+            (Some(None), config.emit_thin_lto_summary.then_some(None))
         } else {
             (None, None)
         };
@@ -958,19 +956,17 @@ pub(crate) fn optimize(
             )
         };
         if let Some(thin_lto_buffer) = thin_lto_buffer {
-            let thin_lto_buffer =
-                unsafe { crate::back::lto::Buffer::from_raw_ptr(thin_lto_buffer) };
-            let thin_lto_summary_buffer =
-                unsafe { crate::back::lto::Buffer::from_raw_ptr(thin_lto_summary_buffer.unwrap()) };
+            let thin_lto_buffer = thin_lto_buffer.unwrap();
             module.thin_lto_buffer = Some(thin_lto_buffer.data().to_vec());
             let bc_summary_out = cgcx.output_filenames.temp_path_for_cgu(
                 OutputType::ThinLinkBitcode,
                 &module.name,
                 cgcx.invocation_temp.as_deref(),
             );
-            if config.emit_thin_lto_summary
+            if let Some(thin_lto_summary_buffer) = thin_lto_summary_buffer
                 && let Some(thin_link_bitcode_filename) = bc_summary_out.file_name()
             {
+                let thin_lto_summary_buffer = thin_lto_summary_buffer.unwrap();
                 let summary_data = thin_lto_summary_buffer.data();
                 prof.artifact_size(
                     "llvm_bitcode_summary",

compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -2372,9 +2372,8 @@ pub(crate) fn LLVMRustOptimize<'a>(
         NoPrepopulatePasses: bool,
         VerifyIR: bool,
         LintIR: bool,
-        ThinLTOBuffer: Option<&mut *mut Buffer>,
-        ThinLTOSummaryBuffer: Option<&mut *mut Buffer>,
-        EmitThinLTOSummary: bool,
+        ThinLTOBuffer: Option<&mut Option<crate::back::lto::Buffer>>,
+        ThinLTOSummaryBuffer: Option<&mut Option<crate::back::lto::Buffer>>,
         MergeFunctions: bool,
         UnrollLoops: bool,
         SLPVectorize: bool,

compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp

@@ -554,9 +554,9 @@ extern "C" LLVMRustResult LLVMRustOptimize(
     LLVMRustPassBuilderOptLevel OptLevelRust, LLVMRustOptStage OptStage,
     bool IsLinkerPluginLTO, bool NoPrepopulatePasses, bool VerifyIR,
     bool LintIR, LLVMRustBuffer **ThinLTOBufferRef,
-    LLVMRustBuffer **ThinLTOSummaryBufferRef, bool EmitThinLTOSummary,
-    bool MergeFunctions, bool UnrollLoops, bool SLPVectorize,
-    bool LoopVectorize, bool DisableSimplifyLibCalls, bool EmitLifetimeMarkers,
+    LLVMRustBuffer **ThinLTOSummaryBufferRef, bool MergeFunctions,
+    bool UnrollLoops, bool SLPVectorize, bool LoopVectorize,
+    bool DisableSimplifyLibCalls, bool EmitLifetimeMarkers,
     registerEnzymeAndPassPipelineFn EnzymePtr, bool PrintBeforeEnzyme,
     bool PrintAfterEnzyme, bool PrintPasses,
     LLVMRustSanitizerOptions *SanitizerOptions, const char *PGOGenPath,
@@ -825,9 +825,12 @@ extern "C" LLVMRustResult LLVMRustOptimize(
           // `ThinLTOPreLinkDefaultPipeline`.
           MPM.addPass(PB.buildThinLTOPreLinkDefaultPipeline(OptLevel));
           MPM.addPass(ThinLTOBitcodeWriterPass(
-              ThinLTODataOS, EmitThinLTOSummary ? &ThinLinkDataOS : nullptr));
+              ThinLTODataOS,
+              ThinLTOSummaryBufferRef ? &ThinLinkDataOS : nullptr));
           *ThinLTOBufferRef = ThinLTOBuffer.release();
-          *ThinLTOSummaryBufferRef = ThinLTOSummaryBuffer.release();
+          if (ThinLTOSummaryBufferRef) {
+            *ThinLTOSummaryBufferRef = ThinLTOSummaryBuffer.release();
+          }
           MPM.addPass(PB.buildModuleOptimizationPipeline(
               OptLevel, ThinOrFullLTOPhase::None));
           MPM.addPass(
@@ -883,12 +886,14 @@ extern "C" LLVMRustResult LLVMRustOptimize(
     // lto is requested. See PR #136840 for background information.
     if (OptStage != LLVMRustOptStage::PreLinkFatLTO) {
       MPM.addPass(ThinLTOBitcodeWriterPass(
-          ThinLTODataOS, EmitThinLTOSummary ? &ThinLinkDataOS : nullptr));
+          ThinLTODataOS, ThinLTOSummaryBufferRef ? &ThinLinkDataOS : nullptr));
     } else {
       MPM.addPass(BitcodeWriterPass(ThinLTODataOS));
     }
     *ThinLTOBufferRef = ThinLTOBuffer.release();
-    *ThinLTOSummaryBufferRef = ThinLTOSummaryBuffer.release();
+    if (ThinLTOSummaryBufferRef) {
+      *ThinLTOSummaryBufferRef = ThinLTOSummaryBuffer.release();
+    }
   }
 
   // now load "-enzyme" pass: