2 files changed, 13 insertions, 3 deletions
diff --git a/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
index d61ec0b641c..373bc5cc581 100644
--- a/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
@@ -139,6 +139,9 @@ extern "C" void LLVMRustCoverageWriteMappingToBuffer(
            RustMappingRegions, NumMappingRegions)) {
     MappingRegions.emplace_back(
         fromRust(Region.Count), fromRust(Region.FalseCount),
+#if LLVM_VERSION_GE(18, 0)
+        coverage::CounterMappingRegion::MCDCParameters{},
+#endif
         Region.FileID, Region.ExpandedFileID,
         Region.LineStart, Region.ColumnStart, Region.LineEnd, Region.ColumnEnd,
         fromRust(Region.Kind));
diff --git a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
index cf3f526400d..6114f7c8678 100644
--- a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
@@ -531,9 +531,12 @@ extern "C" void LLVMRustDisposeTargetMachine(LLVMTargetMachineRef TM) {
 
 // Unfortunately, the LLVM C API doesn't provide a way to create the
 // TargetLibraryInfo pass, so we use this method to do so.
-extern "C" void LLVMRustAddLibraryInfo(LLVMPassManagerRef PMR, LLVMModuleRef M) {
+extern "C" void LLVMRustAddLibraryInfo(LLVMPassManagerRef PMR, LLVMModuleRef M,
+                                       bool DisableSimplifyLibCalls) {
   Triple TargetTriple(unwrap(M)->getTargetTriple());
   TargetLibraryInfoImpl TLII(TargetTriple);
+  if (DisableSimplifyLibCalls)
+    TLII.disableAllFunctions();
   unwrap(PMR)->add(new TargetLibraryInfoWrapperPass(TLII));
 }
 
@@ -700,7 +703,7 @@ LLVMRustOptimize(
     bool IsLinkerPluginLTO,
     bool NoPrepopulatePasses, bool VerifyIR, bool UseThinLTOBuffers,
     bool MergeFunctions, bool UnrollLoops, bool SLPVectorize, bool LoopVectorize,
-    bool EmitLifetimeMarkers,
+    bool DisableSimplifyLibCalls, bool EmitLifetimeMarkers,
     LLVMRustSanitizerOptions *SanitizerOptions,
     const char *PGOGenPath, const char *PGOUsePath,
     bool InstrumentCoverage, const char *InstrProfileOutput,
@@ -787,7 +790,9 @@ LLVMRustOptimize(
     for (auto PluginPath: Plugins) {
       auto Plugin = PassPlugin::Load(PluginPath.str());
       if (!Plugin) {
-        LLVMRustSetLastError(("Failed to load pass plugin" + PluginPath.str()).c_str());
+        auto Err = Plugin.takeError();
+        auto ErrMsg = llvm::toString(std::move(Err));
+        LLVMRustSetLastError(ErrMsg.c_str());
         return LLVMRustResult::Failure;
       }
       Plugin->registerPassBuilderCallbacks(PB);
@@ -798,6 +803,8 @@ LLVMRustOptimize(
 
   Triple TargetTriple(TheModule->getTargetTriple());
   std::unique_ptr<TargetLibraryInfoImpl> TLII(new TargetLibraryInfoImpl(TargetTriple));
+  if (DisableSimplifyLibCalls)
+    TLII->disableAllFunctions();
   FAM.registerPass([&] { return TargetLibraryAnalysis(*TLII); });
 
   PB.registerModuleAnalyses(MAM);