Remove pass initialization code

This is no longer necessary with the new pass manager.

compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -1814,8 +1814,6 @@ extern "C" {
     /// Creates a legacy pass manager -- only used for final codegen.
     pub fn LLVMCreatePassManager<'a>() -> &'a mut PassManager<'a>;
 
-    pub fn LLVMInitializePasses();
-
     pub fn LLVMTimeTraceProfilerInitialize();
 
     pub fn LLVMTimeTraceProfilerFinishThread();

compiler/rustc_codegen_llvm/src/llvm_util.rs

@@ -120,8 +120,6 @@ unsafe fn configure_llvm(sess: &Session) {
         llvm::LLVMTimeTraceProfilerInitialize();
     }
 
-    llvm::LLVMInitializePasses();
-
     rustc_llvm::initialize_available_targets();
 
     llvm::LLVMRustSetLLVMOptions(llvm_args.len() as c_int, llvm_args.as_ptr());

compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp

@@ -9,7 +9,6 @@
 #include "llvm/Analysis/TargetLibraryInfo.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
 #include "llvm/CodeGen/TargetSubtargetInfo.h"
-#include "llvm/InitializePasses.h"
 #include "llvm/IR/AutoUpgrade.h"
 #include "llvm/IR/AssemblyAnnotationWriter.h"
 #include "llvm/IR/IntrinsicInst.h"
@@ -58,22 +57,6 @@ typedef struct LLVMOpaqueTargetMachine *LLVMTargetMachineRef;
 DEFINE_STDCXX_CONVERSION_FUNCTIONS(Pass, LLVMPassRef)
 DEFINE_STDCXX_CONVERSION_FUNCTIONS(TargetMachine, LLVMTargetMachineRef)
 
-extern "C" void LLVMInitializePasses() {
-  PassRegistry &Registry = *PassRegistry::getPassRegistry();
-  initializeCore(Registry);
-  initializeCodeGen(Registry);
-  initializeScalarOpts(Registry);
-  initializeVectorization(Registry);
-  initializeIPO(Registry);
-  initializeAnalysis(Registry);
-  initializeTransformUtils(Registry);
-  initializeInstCombine(Registry);
-#if LLVM_VERSION_LT(16, 0)
-  initializeInstrumentation(Registry);
-#endif
-  initializeTarget(Registry);
-}
-
 extern "C" void LLVMTimeTraceProfilerInitialize() {
   timeTraceProfilerInitialize(
       /* TimeTraceGranularity */ 0,
@@ -1004,7 +987,6 @@ LLVMRustPrintModule(LLVMModuleRef M, const char *Path, DemangleFn Demangle) {
 }
 
 extern "C" void LLVMRustPrintPasses() {
-  LLVMInitializePasses();
   struct MyListener : PassRegistrationListener {
     void passEnumerate(const PassInfo *Info) {
       StringRef PassArg = Info->getPassArgument();