/*
 * Copyright (c) 2015 Andrew Kelley
 *
 * This file is part of zig, which is MIT licensed.
 * See http://opensource.org/licenses/MIT
 */


/*
 * The point of this file is to contain all the LLVM C++ API interaction so that:
 * 1. The compile time of other files is kept under control.
 * 2. Provide a C interface to the LLVM functions we need for self-hosting purposes.
 * 3. Prevent C++ from infecting the rest of the project.
 */

#include "zig_llvm.h"

#include <llvm/Analysis/TargetLibraryInfo.h>
#include <llvm/Analysis/TargetTransformInfo.h>
#include <llvm/IR/DIBuilder.h>
#include <llvm/IR/DiagnosticInfo.h>
#include <llvm/IR/IRBuilder.h>
#include <llvm/IR/InlineAsm.h>
#include <llvm/IR/Instructions.h>
#include <llvm/IR/LegacyPassManager.h>
#include <llvm/IR/Module.h>
#include <llvm/IR/Verifier.h>
#include <llvm/InitializePasses.h>
#include <llvm/MC/SubtargetFeature.h>
#include <llvm/PassRegistry.h>
#include <llvm/Support/FileSystem.h>
#include <llvm/Support/TargetParser.h>
#include <llvm/Support/raw_ostream.h>
#include <llvm/Target/TargetMachine.h>
#include <llvm/Transforms/Coroutines.h>
#include <llvm/Transforms/IPO.h>
#include <llvm/Transforms/IPO/PassManagerBuilder.h>
#include <llvm/Transforms/IPO/AlwaysInliner.h>
#include <llvm/Transforms/Scalar.h>

#include <lld/Common/Driver.h>

#include <new>

#include <stdlib.h>

using namespace llvm;

void ZigLLVMInitializeLoopStrengthReducePass(LLVMPassRegistryRef R) {
    initializeLoopStrengthReducePass(*unwrap(R));
}

void ZigLLVMInitializeLowerIntrinsicsPass(LLVMPassRegistryRef R) {
    initializeLowerIntrinsicsPass(*unwrap(R));
}

char *ZigLLVMGetHostCPUName(void) {
    return strdup((const char *)sys::getHostCPUName().bytes_begin());
}

char *ZigLLVMGetNativeFeatures(void) {
    SubtargetFeatures features;

    StringMap<bool> host_features;
    if (sys::getHostCPUFeatures(host_features)) {
        for (auto &F : host_features)
            features.AddFeature(F.first(), F.second);
    }

    return strdup((const char *)StringRef(features.getString()).bytes_begin());
}

static void addDiscriminatorsPass(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM) {
    PM.add(createAddDiscriminatorsPass());
}

#ifndef NDEBUG
static const bool assertions_on = true;
#else
static const bool assertions_on = false;
#endif

bool ZigLLVMTargetMachineEmitToFile(LLVMTargetMachineRef targ_machine_ref, LLVMModuleRef module_ref,
        const char *filename, ZigLLVM_EmitOutputType output_type, char **error_message, bool is_debug, bool is_small)
{
    std::error_code EC;
    raw_fd_ostream dest(filename, EC, sys::fs::F_None);
    if (EC) {
        *error_message = strdup((const char *)StringRef(EC.message()).bytes_begin());
        return true;
    }
    TargetMachine* target_machine = reinterpret_cast<TargetMachine*>(targ_machine_ref);
    target_machine->setO0WantsFastISel(true);

    Module* module = unwrap(module_ref);

    PassManagerBuilder *PMBuilder = new(std::nothrow) PassManagerBuilder();
    if (PMBuilder == nullptr) {
        *error_message = strdup("memory allocation failure");
        return true;
    }
    PMBuilder->OptLevel = target_machine->getOptLevel();
    PMBuilder->SizeLevel = is_small ? 2 : 0;

    PMBuilder->DisableTailCalls = is_debug;
    PMBuilder->DisableUnitAtATime = is_debug;
    PMBuilder->DisableUnrollLoops = is_debug;
    PMBuilder->SLPVectorize = !is_debug;
    PMBuilder->LoopVectorize = !is_debug;
    PMBuilder->RerollLoops = !is_debug;
    // Leaving NewGVN as default (off) because when on it caused issue #673
    //PMBuilder->NewGVN = !is_debug;
    PMBuilder->DisableGVNLoadPRE = is_debug;
    PMBuilder->VerifyInput = assertions_on;
    PMBuilder->VerifyOutput = assertions_on;
    PMBuilder->MergeFunctions = !is_debug;
    PMBuilder->PrepareForLTO = false;
    PMBuilder->PrepareForThinLTO = false;
    PMBuilder->PerformThinLTO = false;

    TargetLibraryInfoImpl tlii(Triple(module->getTargetTriple()));
    PMBuilder->LibraryInfo = &tlii;

    if (is_debug) {
        PMBuilder->Inliner = createAlwaysInlinerLegacyPass(false);
    } else {
        target_machine->adjustPassManager(*PMBuilder);

        PMBuilder->addExtension(PassManagerBuilder::EP_EarlyAsPossible, addDiscriminatorsPass);
        PMBuilder->Inliner = createFunctionInliningPass(PMBuilder->OptLevel, PMBuilder->SizeLevel, false);
    }

    addCoroutinePassesToExtensionPoints(*PMBuilder);

    // Set up the per-function pass manager.
    legacy::FunctionPassManager FPM = legacy::FunctionPassManager(module);
    auto tliwp = new(std::nothrow) TargetLibraryInfoWrapperPass(tlii);
    FPM.add(tliwp);
    FPM.add(createTargetTransformInfoWrapperPass(target_machine->getTargetIRAnalysis()));
    if (assertions_on) {
        FPM.add(createVerifierPass());
    }
    PMBuilder->populateFunctionPassManager(FPM);

    // Set up the per-module pass manager.
    legacy::PassManager MPM;
    MPM.add(createTargetTransformInfoWrapperPass(target_machine->getTargetIRAnalysis()));
    PMBuilder->populateModulePassManager(MPM);

    // Set output pass.
    TargetMachine::CodeGenFileType ft;
    if (output_type != ZigLLVM_EmitLLVMIr) {
        switch (output_type) {
            case ZigLLVM_EmitAssembly:
                ft = TargetMachine::CGFT_AssemblyFile;
                break;
            case ZigLLVM_EmitBinary:
                ft = TargetMachine::CGFT_ObjectFile;
                break;
            default:
                abort();
        }

        if (target_machine->addPassesToEmitFile(MPM, dest, ft)) {
            *error_message = strdup("TargetMachine can't emit a file of this type");
            return true;
        }
    }

    // run per function optimization passes
    FPM.doInitialization();
    for (Function &F : *module)
      if (!F.isDeclaration())
        FPM.run(F);
    FPM.doFinalization();

    MPM.run(*module);

    if (output_type == ZigLLVM_EmitLLVMIr) {
        if (LLVMPrintModuleToFile(module_ref, filename, error_message)) {
            return true;
        }
    }

    return false;
}

ZIG_EXTERN_C LLVMTypeRef ZigLLVMTokenTypeInContext(LLVMContextRef context_ref) {
  return wrap(Type::getTokenTy(*unwrap(context_ref)));
}

LLVMValueRef ZigLLVMBuildCall(LLVMBuilderRef B, LLVMValueRef Fn, LLVMValueRef *Args,
        unsigned NumArgs, unsigned CC, ZigLLVM_FnInline fn_inline, const char *Name)
{
    CallInst *call_inst = CallInst::Create(unwrap(Fn), makeArrayRef(unwrap(Args), NumArgs), Name);
    call_inst->setCallingConv(CC);
    switch (fn_inline) {
        case ZigLLVM_FnInlineAuto:
            break;
        case ZigLLVM_FnInlineAlways:
            call_inst->addAttribute(AttributeList::FunctionIndex, Attribute::AlwaysInline);
            break;
        case ZigLLVM_FnInlineNever:
            call_inst->addAttribute(AttributeList::FunctionIndex, Attribute::NoInline);
            break;
    }
    return wrap(unwrap(B)->Insert(call_inst));
}

void ZigLLVMFnSetSubprogram(LLVMValueRef fn, ZigLLVMDISubprogram *subprogram) {
    assert( isa<Function>(unwrap(fn)) );
    Function *unwrapped_function = reinterpret_cast<Function*>(unwrap(fn));
    unwrapped_function->setSubprogram(reinterpret_cast<DISubprogram*>(subprogram));
}


ZigLLVMDIType *ZigLLVMCreateDebugPointerType(ZigLLVMDIBuilder *dibuilder, ZigLLVMDIType *pointee_type,
        uint64_t size_in_bits, uint64_t align_in_bits, const char *name)
{
    DIType *di_type = reinterpret_cast<DIBuilder*>(dibuilder)->createPointerType(
            reinterpret_cast<DIType*>(pointee_type), size_in_bits, align_in_bits, Optional<unsigned>(), name);
    return reinterpret_cast<ZigLLVMDIType*>(di_type);
}

ZigLLVMDIType *ZigLLVMCreateDebugBasicType(ZigLLVMDIBuilder *dibuilder, const char *name,
        uint64_t size_in_bits, unsigned encoding)
{
    DIType *di_type = reinterpret_cast<DIBuilder*>(dibuilder)->createBasicType(
            name, size_in_bits, encoding);
    return reinterpret_cast<ZigLLVMDIType*>(di_type);
}

ZigLLVMDIType *ZigLLVMCreateDebugArrayType(ZigLLVMDIBuilder *dibuilder, uint64_t size_in_bits,
        uint64_t align_in_bits, ZigLLVMDIType *elem_type, int elem_count)
{
    SmallVector<Metadata *, 1> subrange;
    subrange.push_back(reinterpret_cast<DIBuilder*>(dibuilder)->getOrCreateSubrange(0, elem_count));
    DIType *di_type = reinterpret_cast<DIBuilder*>(dibuilder)->createArrayType(
            size_in_bits, align_in_bits,
            reinterpret_cast<DIType*>(elem_type),
            reinterpret_cast<DIBuilder*>(dibuilder)->getOrCreateArray(subrange));
    return reinterpret_cast<ZigLLVMDIType*>(di_type);
}

ZigLLVMDIEnumerator *ZigLLVMCreateDebugEnumerator(ZigLLVMDIBuilder *dibuilder, const char *name, int64_t val) {
    DIEnumerator *di_enumerator = reinterpret_cast<DIBuilder*>(dibuilder)->createEnumerator(name, val);
    return reinterpret_cast<ZigLLVMDIEnumerator*>(di_enumerator);
}

ZigLLVMDIType *ZigLLVMCreateDebugEnumerationType(ZigLLVMDIBuilder *dibuilder, ZigLLVMDIScope *scope,
        const char *name, ZigLLVMDIFile *file, unsigned line_number, uint64_t size_in_bits,
        uint64_t align_in_bits, ZigLLVMDIEnumerator **enumerator_array, int enumerator_array_len,
        ZigLLVMDIType *underlying_type, const char *unique_id)
{
    SmallVector<Metadata *, 8> fields;
    for (int i = 0; i < enumerator_array_len; i += 1) {
        DIEnumerator *dienumerator = reinterpret_cast<DIEnumerator*>(enumerator_array[i]);
        fields.push_back(dienumerator);
    }
    DIType *di_type = reinterpret_cast<DIBuilder*>(dibuilder)->createEnumerationType(
            reinterpret_cast<DIScope*>(scope),
            name,
            reinterpret_cast<DIFile*>(file),
            line_number, size_in_bits, align_in_bits,
            reinterpret_cast<DIBuilder*>(dibuilder)->getOrCreateArray(fields),
            reinterpret_cast<DIType*>(underlying_type),
            unique_id);
    return reinterpret_cast<ZigLLVMDIType*>(di_type);
}

ZigLLVMDIType *ZigLLVMCreateDebugMemberType(ZigLLVMDIBuilder *dibuilder, ZigLLVMDIScope *scope,
        const char *name, ZigLLVMDIFile *file, unsigned line, uint64_t size_in_bits,
        uint64_t align_in_bits, uint64_t offset_in_bits, unsigned flags, ZigLLVMDIType *type)
{
    assert(flags == 0);
    DIType *di_type = reinterpret_cast<DIBuilder*>(dibuilder)->createMemberType(
            reinterpret_cast<DIScope*>(scope),
            name,
            reinterpret_cast<DIFile*>(file),
            line, size_in_bits, align_in_bits, offset_in_bits, DINode::FlagZero,
            reinterpret_cast<DIType*>(type));
    return reinterpret_cast<ZigLLVMDIType*>(di_type);
}

ZigLLVMDIType *ZigLLVMCreateDebugUnionType(ZigLLVMDIBuilder *dibuilder, ZigLLVMDIScope *scope,
        const char *name, ZigLLVMDIFile *file, unsigned line_number, uint64_t size_in_bits,
        uint64_t align_in_bits, unsigned flags, ZigLLVMDIType **types_array, int types_array_len,
        unsigned run_time_lang, const char *unique_id)
{
    SmallVector<Metadata *, 8> fields;
    for (int i = 0; i < types_array_len; i += 1) {
        DIType *ditype = reinterpret_cast<DIType*>(types_array[i]);
        fields.push_back(ditype);
    }
    assert(flags == 0);
    DIType *di_type = reinterpret_cast<DIBuilder*>(dibuilder)->createUnionType(
            reinterpret_cast<DIScope*>(scope),
            name,
            reinterpret_cast<DIFile*>(file),
            line_number, size_in_bits, align_in_bits, DINode::FlagZero,
            reinterpret_cast<DIBuilder*>(dibuilder)->getOrCreateArray(fields),
            run_time_lang, unique_id);
    return reinterpret_cast<ZigLLVMDIType*>(di_type);
}

ZigLLVMDIType *ZigLLVMCreateDebugStructType(ZigLLVMDIBuilder *dibuilder, ZigLLVMDIScope *scope,
        const char *name, ZigLLVMDIFile *file, unsigned line_number, uint64_t size_in_bits,
        uint64_t align_in_bits, unsigned flags, ZigLLVMDIType *derived_from,
        ZigLLVMDIType **types_array, int types_array_len, unsigned run_time_lang, ZigLLVMDIType *vtable_holder,
        const char *unique_id)
{
    SmallVector<Metadata *, 8> fields;
    for (int i = 0; i < types_array_len; i += 1) {
        DIType *ditype = reinterpret_cast<DIType*>(types_array[i]);
        fields.push_back(ditype);
    }
    assert(flags == 0);
    DIType *di_type = reinterpret_cast<DIBuilder*>(dibuilder)->createStructType(
            reinterpret_cast<DIScope*>(scope),
            name,
            reinterpret_cast<DIFile*>(file),
            line_number, size_in_bits, align_in_bits, DINode::FlagZero,
            reinterpret_cast<DIType*>(derived_from),
            reinterpret_cast<DIBuilder*>(dibuilder)->getOrCreateArray(fields),
            run_time_lang,
            reinterpret_cast<DIType*>(vtable_holder),
            unique_id);
    return reinterpret_cast<ZigLLVMDIType*>(di_type);
}

ZigLLVMDIType *ZigLLVMCreateReplaceableCompositeType(ZigLLVMDIBuilder *dibuilder, unsigned tag,
        const char *name, ZigLLVMDIScope *scope, ZigLLVMDIFile *file, unsigned line)
{
    DIType *di_type = reinterpret_cast<DIBuilder*>(dibuilder)->createReplaceableCompositeType(
            tag, name,
            reinterpret_cast<DIScope*>(scope),
            reinterpret_cast<DIFile*>(file),
            line);
    return reinterpret_cast<ZigLLVMDIType*>(di_type);
}

ZigLLVMDIType *ZigLLVMCreateDebugForwardDeclType(ZigLLVMDIBuilder *dibuilder, unsigned tag,
        const char *name, ZigLLVMDIScope *scope, ZigLLVMDIFile *file, unsigned line)
{
    DIType *di_type = reinterpret_cast<DIBuilder*>(dibuilder)->createForwardDecl(
            tag, name,
            reinterpret_cast<DIScope*>(scope),
            reinterpret_cast<DIFile*>(file),
            line);
    return reinterpret_cast<ZigLLVMDIType*>(di_type);
}

void ZigLLVMReplaceTemporary(ZigLLVMDIBuilder *dibuilder, ZigLLVMDIType *type,
        ZigLLVMDIType *replacement)
{
    reinterpret_cast<DIBuilder*>(dibuilder)->replaceTemporary(
            TempDIType(reinterpret_cast<DIType*>(type)),
            reinterpret_cast<DIType*>(replacement));
}

void ZigLLVMReplaceDebugArrays(ZigLLVMDIBuilder *dibuilder, ZigLLVMDIType *type,
        ZigLLVMDIType **types_array, int types_array_len)
{
    SmallVector<Metadata *, 8> fields;
    for (int i = 0; i < types_array_len; i += 1) {
        DIType *ditype = reinterpret_cast<DIType*>(types_array[i]);
        fields.push_back(ditype);
    }
    DICompositeType *composite_type = (DICompositeType*)reinterpret_cast<DIType*>(type);
    reinterpret_cast<DIBuilder*>(dibuilder)->replaceArrays(
            composite_type,
            reinterpret_cast<DIBuilder*>(dibuilder)->getOrCreateArray(fields));
}

ZigLLVMDIType *ZigLLVMCreateSubroutineType(ZigLLVMDIBuilder *dibuilder_wrapped,
        ZigLLVMDIType **types_array, int types_array_len, unsigned flags)
{
    SmallVector<Metadata *, 8> types;
    for (int i = 0; i < types_array_len; i += 1) {
        DIType *ditype = reinterpret_cast<DIType*>(types_array[i]);
        types.push_back(ditype);
    }
    assert(flags == 0);
    DIBuilder *dibuilder = reinterpret_cast<DIBuilder*>(dibuilder_wrapped);
    DISubroutineType *subroutine_type = dibuilder->createSubroutineType(
            dibuilder->getOrCreateTypeArray(types),
            DINode::FlagZero);
    DIType *ditype = subroutine_type;
    return reinterpret_cast<ZigLLVMDIType*>(ditype);
}

unsigned ZigLLVMEncoding_DW_ATE_unsigned(void) {
    return dwarf::DW_ATE_unsigned;
}

unsigned ZigLLVMEncoding_DW_ATE_signed(void) {
    return dwarf::DW_ATE_signed;
}

unsigned ZigLLVMEncoding_DW_ATE_float(void) {
    return dwarf::DW_ATE_float;
}

unsigned ZigLLVMEncoding_DW_ATE_boolean(void) {
    return dwarf::DW_ATE_boolean;
}

unsigned ZigLLVMEncoding_DW_ATE_unsigned_char(void) {
    return dwarf::DW_ATE_unsigned_char;
}

unsigned ZigLLVMEncoding_DW_ATE_signed_char(void) {
    return dwarf::DW_ATE_signed_char;
}

unsigned ZigLLVMLang_DW_LANG_C99(void) {
    return dwarf::DW_LANG_C99;
}

unsigned ZigLLVMTag_DW_variable(void) {
    return dwarf::DW_TAG_variable;
}

unsigned ZigLLVMTag_DW_structure_type(void) {
    return dwarf::DW_TAG_structure_type;
}

unsigned ZigLLVMTag_DW_enumeration_type(void) {
    return dwarf::DW_TAG_enumeration_type;
}

unsigned ZigLLVMTag_DW_union_type(void) {
    return dwarf::DW_TAG_union_type;
}

ZigLLVMDIBuilder *ZigLLVMCreateDIBuilder(LLVMModuleRef module, bool allow_unresolved) {
    DIBuilder *di_builder = new(std::nothrow) DIBuilder(*unwrap(module), allow_unresolved);
    if (di_builder == nullptr)
        return nullptr;
    return reinterpret_cast<ZigLLVMDIBuilder *>(di_builder);
}

void ZigLLVMDisposeDIBuilder(ZigLLVMDIBuilder *dbuilder) {
    DIBuilder *di_builder = reinterpret_cast<DIBuilder *>(dbuilder);
    delete di_builder;
}

void ZigLLVMSetCurrentDebugLocation(LLVMBuilderRef builder, int line, int column, ZigLLVMDIScope *scope) {
    unwrap(builder)->SetCurrentDebugLocation(DebugLoc::get(
                line, column, reinterpret_cast<DIScope*>(scope)));
}

void ZigLLVMClearCurrentDebugLocation(LLVMBuilderRef builder) {
    unwrap(builder)->SetCurrentDebugLocation(DebugLoc());
}


ZigLLVMDILexicalBlock *ZigLLVMCreateLexicalBlock(ZigLLVMDIBuilder *dbuilder, ZigLLVMDIScope *scope,
        ZigLLVMDIFile *file, unsigned line, unsigned col)
{
    DILexicalBlock *result = reinterpret_cast<DIBuilder*>(dbuilder)->createLexicalBlock(
            reinterpret_cast<DIScope*>(scope),
            reinterpret_cast<DIFile*>(file),
            line,
            col);
    return reinterpret_cast<ZigLLVMDILexicalBlock*>(result);
}

ZigLLVMDILocalVariable *ZigLLVMCreateAutoVariable(ZigLLVMDIBuilder *dbuilder,
        ZigLLVMDIScope *scope, const char *name, ZigLLVMDIFile *file, unsigned line_no,
        ZigLLVMDIType *type, bool always_preserve, unsigned flags)
{
    assert(flags == 0);
    DILocalVariable *result = reinterpret_cast<DIBuilder*>(dbuilder)->createAutoVariable(
            reinterpret_cast<DIScope*>(scope),
            name,
            reinterpret_cast<DIFile*>(file),
            line_no,
            reinterpret_cast<DIType*>(type),
            always_preserve,
            DINode::FlagZero);
    return reinterpret_cast<ZigLLVMDILocalVariable*>(result);
}

ZigLLVMDIGlobalVariable *ZigLLVMCreateGlobalVariable(ZigLLVMDIBuilder *dbuilder,
    ZigLLVMDIScope *scope, const char *name, const char *linkage_name, ZigLLVMDIFile *file,
    unsigned line_no, ZigLLVMDIType *di_type, bool is_local_to_unit)
{
    DIGlobalVariableExpression *result = reinterpret_cast<DIBuilder*>(dbuilder)->createGlobalVariableExpression(
        reinterpret_cast<DIScope*>(scope),
        name,
        linkage_name,
        reinterpret_cast<DIFile*>(file),
        line_no,
        reinterpret_cast<DIType*>(di_type),
        is_local_to_unit);
    return reinterpret_cast<ZigLLVMDIGlobalVariable*>(result);
}

ZigLLVMDILocalVariable *ZigLLVMCreateParameterVariable(ZigLLVMDIBuilder *dbuilder,
        ZigLLVMDIScope *scope, const char *name, ZigLLVMDIFile *file, unsigned line_no,
        ZigLLVMDIType *type, bool always_preserve, unsigned flags, unsigned arg_no)
{
    assert(flags == 0);
    DILocalVariable *result = reinterpret_cast<DIBuilder*>(dbuilder)->createParameterVariable(
            reinterpret_cast<DIScope*>(scope),
            name,
            arg_no,
            reinterpret_cast<DIFile*>(file),
            line_no,
            reinterpret_cast<DIType*>(type),
            always_preserve,
            DINode::FlagZero);
    return reinterpret_cast<ZigLLVMDILocalVariable*>(result);
}

ZigLLVMDIScope *ZigLLVMLexicalBlockToScope(ZigLLVMDILexicalBlock *lexical_block) {
    DIScope *scope = reinterpret_cast<DILexicalBlock*>(lexical_block);
    return reinterpret_cast<ZigLLVMDIScope*>(scope);
}

ZigLLVMDIScope *ZigLLVMCompileUnitToScope(ZigLLVMDICompileUnit *compile_unit) {
    DIScope *scope = reinterpret_cast<DICompileUnit*>(compile_unit);
    return reinterpret_cast<ZigLLVMDIScope*>(scope);
}

ZigLLVMDIScope *ZigLLVMFileToScope(ZigLLVMDIFile *difile) {
    DIScope *scope = reinterpret_cast<DIFile*>(difile);
    return reinterpret_cast<ZigLLVMDIScope*>(scope);
}

ZigLLVMDIScope *ZigLLVMSubprogramToScope(ZigLLVMDISubprogram *subprogram) {
    DIScope *scope = reinterpret_cast<DISubprogram*>(subprogram);
    return reinterpret_cast<ZigLLVMDIScope*>(scope);
}

ZigLLVMDIScope *ZigLLVMTypeToScope(ZigLLVMDIType *type) {
    DIScope *scope = reinterpret_cast<DIType*>(type);
    return reinterpret_cast<ZigLLVMDIScope*>(scope);
}

ZigLLVMDICompileUnit *ZigLLVMCreateCompileUnit(ZigLLVMDIBuilder *dibuilder,
        unsigned lang, ZigLLVMDIFile *difile, const char *producer,
        bool is_optimized, const char *flags, unsigned runtime_version, const char *split_name,
        uint64_t dwo_id, bool emit_debug_info)
{
    DICompileUnit *result = reinterpret_cast<DIBuilder*>(dibuilder)->createCompileUnit(
            lang,
            reinterpret_cast<DIFile*>(difile),
            producer, is_optimized, flags, runtime_version, split_name,
            (emit_debug_info ? DICompileUnit::DebugEmissionKind::FullDebug : DICompileUnit::DebugEmissionKind::NoDebug),
            dwo_id);
    return reinterpret_cast<ZigLLVMDICompileUnit*>(result);
}


ZigLLVMDIFile *ZigLLVMCreateFile(ZigLLVMDIBuilder *dibuilder, const char *filename, const char *directory) {
    DIFile *result = reinterpret_cast<DIBuilder*>(dibuilder)->createFile(filename, directory);
    return reinterpret_cast<ZigLLVMDIFile*>(result);
}

ZigLLVMDISubprogram *ZigLLVMCreateFunction(ZigLLVMDIBuilder *dibuilder, ZigLLVMDIScope *scope,
        const char *name, const char *linkage_name, ZigLLVMDIFile *file, unsigned lineno,
        ZigLLVMDIType *fn_di_type, bool is_local_to_unit, bool is_definition, unsigned scope_line,
        unsigned flags, bool is_optimized, ZigLLVMDISubprogram *decl_subprogram)
{
    DISubroutineType *di_sub_type = static_cast<DISubroutineType*>(reinterpret_cast<DIType*>(fn_di_type));
    assert(flags == 0);
    DISubprogram *result = reinterpret_cast<DIBuilder*>(dibuilder)->createFunction(
            reinterpret_cast<DIScope*>(scope),
            name, linkage_name,
            reinterpret_cast<DIFile*>(file),
            lineno,
            di_sub_type,
            is_local_to_unit, is_definition, scope_line, DINode::FlagZero, is_optimized,
            nullptr,
            reinterpret_cast<DISubprogram *>(decl_subprogram));
    return reinterpret_cast<ZigLLVMDISubprogram*>(result);
}

void ZigLLVMDIBuilderFinalize(ZigLLVMDIBuilder *dibuilder) {
    reinterpret_cast<DIBuilder*>(dibuilder)->finalize();
}

LLVMValueRef ZigLLVMInsertDeclareAtEnd(ZigLLVMDIBuilder *dibuilder, LLVMValueRef storage,
        ZigLLVMDILocalVariable *var_info, ZigLLVMDILocation *debug_loc, LLVMBasicBlockRef basic_block_ref)
{
    Instruction *result = reinterpret_cast<DIBuilder*>(dibuilder)->insertDeclare(
            unwrap(storage),
            reinterpret_cast<DILocalVariable *>(var_info),
            reinterpret_cast<DIBuilder*>(dibuilder)->createExpression(),
            reinterpret_cast<DILocation*>(debug_loc),
            static_cast<BasicBlock*>(unwrap(basic_block_ref)));
    return wrap(result);
}

LLVMValueRef ZigLLVMInsertDeclare(ZigLLVMDIBuilder *dibuilder, LLVMValueRef storage,
        ZigLLVMDILocalVariable *var_info, ZigLLVMDILocation *debug_loc, LLVMValueRef insert_before_instr)
{
    Instruction *result = reinterpret_cast<DIBuilder*>(dibuilder)->insertDeclare(
            unwrap(storage),
            reinterpret_cast<DILocalVariable *>(var_info),
            reinterpret_cast<DIBuilder*>(dibuilder)->createExpression(),
            reinterpret_cast<DILocation*>(debug_loc),
            static_cast<Instruction*>(unwrap(insert_before_instr)));
    return wrap(result);
}

ZigLLVMDILocation *ZigLLVMGetDebugLoc(unsigned line, unsigned col, ZigLLVMDIScope *scope) {
    DebugLoc debug_loc = DebugLoc::get(line, col, reinterpret_cast<DIScope*>(scope), nullptr);
    return reinterpret_cast<ZigLLVMDILocation*>(debug_loc.get());
}

void ZigLLVMSetFastMath(LLVMBuilderRef builder_wrapped, bool on_state) {
    if (on_state) {
        FastMathFlags fmf;
        fmf.setFast();
        unwrap(builder_wrapped)->setFastMathFlags(fmf);
    } else {
        unwrap(builder_wrapped)->clearFastMathFlags();
    }
}

void ZigLLVMAddFunctionAttr(LLVMValueRef fn_ref, const char *attr_name, const char *attr_value) {
    Function *func = unwrap<Function>(fn_ref);
    const AttributeList attr_set = func->getAttributes();
    AttrBuilder attr_builder;
    if (attr_value) {
        attr_builder.addAttribute(attr_name, attr_value);
    } else {
        attr_builder.addAttribute(attr_name);
    }
    const AttributeList new_attr_set = attr_set.addAttributes(func->getContext(),
            AttributeList::FunctionIndex, attr_builder);
    func->setAttributes(new_attr_set);
}

void ZigLLVMAddFunctionAttrCold(LLVMValueRef fn_ref) {
    Function *func = unwrap<Function>(fn_ref);
    const AttributeList attr_set = func->getAttributes();
    const AttributeList new_attr_set = attr_set.addAttribute(func->getContext(), AttributeList::FunctionIndex,
            Attribute::Cold);
    func->setAttributes(new_attr_set);
}

void ZigLLVMParseCommandLineOptions(size_t argc, const char *const *argv) {
    llvm::cl::ParseCommandLineOptions(argc, argv);
}


static_assert((Triple::ArchType)ZigLLVM_LastArchType == Triple::LastArchType, "");
static_assert((Triple::VendorType)ZigLLVM_LastVendorType == Triple::LastVendorType, "");
static_assert((Triple::OSType)ZigLLVM_LastOSType == Triple::LastOSType, "");
static_assert((Triple::EnvironmentType)ZigLLVM_LastEnvironmentType == Triple::LastEnvironmentType, "");
static_assert((Triple::SubArchType)ZigLLVM_KalimbaSubArch_v5 == Triple::KalimbaSubArch_v5, "");

static_assert((Triple::ObjectFormatType)ZigLLVM_UnknownObjectFormat == Triple::UnknownObjectFormat, "");
static_assert((Triple::ObjectFormatType)ZigLLVM_COFF == Triple::COFF, "");
static_assert((Triple::ObjectFormatType)ZigLLVM_ELF == Triple::ELF, "");
static_assert((Triple::ObjectFormatType)ZigLLVM_MachO == Triple::MachO, "");
static_assert((Triple::ObjectFormatType)ZigLLVM_Wasm == Triple::Wasm, "");

const char *ZigLLVMGetArchTypeName(ZigLLVM_ArchType arch) {
    return (const char*)Triple::getArchTypeName((Triple::ArchType)arch).bytes_begin();
}

const char *ZigLLVMGetVendorTypeName(ZigLLVM_VendorType vendor) {
    return (const char*)Triple::getVendorTypeName((Triple::VendorType)vendor).bytes_begin();
}

const char *ZigLLVMGetOSTypeName(ZigLLVM_OSType os) {
    return (const char*)Triple::getOSTypeName((Triple::OSType)os).bytes_begin();
}

const char *ZigLLVMGetEnvironmentTypeName(ZigLLVM_EnvironmentType env_type) {
    return (const char*)Triple::getEnvironmentTypeName((Triple::EnvironmentType)env_type).bytes_begin();
}

void ZigLLVMGetNativeTarget(ZigLLVM_ArchType *arch_type, ZigLLVM_SubArchType *sub_arch_type,
        ZigLLVM_VendorType *vendor_type, ZigLLVM_OSType *os_type, ZigLLVM_EnvironmentType *environ_type,
        ZigLLVM_ObjectFormatType *oformat)
{
    char *native_triple = LLVMGetDefaultTargetTriple();
    Triple triple(native_triple);

    *arch_type = (ZigLLVM_ArchType)triple.getArch();
    *sub_arch_type = (ZigLLVM_SubArchType)triple.getSubArch();
    *vendor_type = (ZigLLVM_VendorType)triple.getVendor();
    *os_type = (ZigLLVM_OSType)triple.getOS();
    *environ_type = (ZigLLVM_EnvironmentType)triple.getEnvironment();
    *oformat = (ZigLLVM_ObjectFormatType)triple.getObjectFormat();

    free(native_triple);
}

const char *ZigLLVMGetSubArchTypeName(ZigLLVM_SubArchType sub_arch) {
    switch (sub_arch) {
        case ZigLLVM_NoSubArch:
            return "(none)";
        case ZigLLVM_ARMSubArch_v8_3a:
            return "v8_3a";
        case ZigLLVM_ARMSubArch_v8_2a:
            return "v8_2a";
        case ZigLLVM_ARMSubArch_v8_1a:
            return "v8_1a";
        case ZigLLVM_ARMSubArch_v8:
            return "v8";
        case ZigLLVM_ARMSubArch_v8r:
            return "v8r";
        case ZigLLVM_ARMSubArch_v8m_baseline:
            return "v8m_baseline";
        case ZigLLVM_ARMSubArch_v8m_mainline:
            return "v8m_mainline";
        case ZigLLVM_ARMSubArch_v7:
            return "v7";
        case ZigLLVM_ARMSubArch_v7em:
            return "v7em";
        case ZigLLVM_ARMSubArch_v7m:
            return "v7m";
        case ZigLLVM_ARMSubArch_v7s:
            return "v7s";
        case ZigLLVM_ARMSubArch_v7k:
            return "v7k";
        case ZigLLVM_ARMSubArch_v7ve:
            return "v7ve";
        case ZigLLVM_ARMSubArch_v6:
            return "v6";
        case ZigLLVM_ARMSubArch_v6m:
            return "v6m";
        case ZigLLVM_ARMSubArch_v6k:
            return "v6k";
        case ZigLLVM_ARMSubArch_v6t2:
            return "v6t2";
        case ZigLLVM_ARMSubArch_v5:
            return "v5";
        case ZigLLVM_ARMSubArch_v5te:
            return "v5te";
        case ZigLLVM_ARMSubArch_v4t:
            return "v4t";
        case ZigLLVM_KalimbaSubArch_v3:
            return "v3";
        case ZigLLVM_KalimbaSubArch_v4:
            return "v4";
        case ZigLLVM_KalimbaSubArch_v5:
            return "v5";
    }
    abort();
}

void ZigLLVMAddModuleDebugInfoFlag(LLVMModuleRef module) {
    unwrap(module)->addModuleFlag(Module::Warning, "Debug Info Version", DEBUG_METADATA_VERSION);
}

void ZigLLVMAddModuleCodeViewFlag(LLVMModuleRef module) {
    unwrap(module)->addModuleFlag(Module::Warning, "CodeView", 1);
}

static AtomicOrdering mapFromLLVMOrdering(LLVMAtomicOrdering Ordering) {
    switch (Ordering) {
        case LLVMAtomicOrderingNotAtomic: return AtomicOrdering::NotAtomic;
        case LLVMAtomicOrderingUnordered: return AtomicOrdering::Unordered;
        case LLVMAtomicOrderingMonotonic: return AtomicOrdering::Monotonic;
        case LLVMAtomicOrderingAcquire: return AtomicOrdering::Acquire;
        case LLVMAtomicOrderingRelease: return AtomicOrdering::Release;
        case LLVMAtomicOrderingAcquireRelease: return AtomicOrdering::AcquireRelease;
        case LLVMAtomicOrderingSequentiallyConsistent: return AtomicOrdering::SequentiallyConsistent;
    }
    abort();
}

LLVMValueRef ZigLLVMBuildCmpXchg(LLVMBuilderRef builder, LLVMValueRef ptr, LLVMValueRef cmp,
        LLVMValueRef new_val, LLVMAtomicOrdering success_ordering,
        LLVMAtomicOrdering failure_ordering, bool is_weak)
{
    AtomicCmpXchgInst *inst = unwrap(builder)->CreateAtomicCmpXchg(unwrap(ptr), unwrap(cmp),
                unwrap(new_val), mapFromLLVMOrdering(success_ordering), mapFromLLVMOrdering(failure_ordering));
    inst->setWeak(is_weak);
    return wrap(inst);
}

LLVMValueRef ZigLLVMBuildNSWShl(LLVMBuilderRef builder, LLVMValueRef LHS, LLVMValueRef RHS,
        const char *name)
{
    return wrap(unwrap(builder)->CreateShl(unwrap(LHS), unwrap(RHS), name, false, true));
}

LLVMValueRef ZigLLVMBuildNUWShl(LLVMBuilderRef builder, LLVMValueRef LHS, LLVMValueRef RHS,
        const char *name)
{
    return wrap(unwrap(builder)->CreateShl(unwrap(LHS), unwrap(RHS), name, true, false));
}

LLVMValueRef ZigLLVMBuildLShrExact(LLVMBuilderRef builder, LLVMValueRef LHS, LLVMValueRef RHS,
        const char *name)
{
    return wrap(unwrap(builder)->CreateLShr(unwrap(LHS), unwrap(RHS), name, true));
}

LLVMValueRef ZigLLVMBuildAShrExact(LLVMBuilderRef builder, LLVMValueRef LHS, LLVMValueRef RHS,
        const char *name)
{
    return wrap(unwrap(builder)->CreateAShr(unwrap(LHS), unwrap(RHS), name, true));
}


class MyOStream: public raw_ostream {
    public:
        MyOStream(void (*_append_diagnostic)(void *, const char *, size_t), void *_context) :
            raw_ostream(true), append_diagnostic(_append_diagnostic), context(_context), pos(0) {

        }
        void write_impl(const char *ptr, size_t len) override {
            append_diagnostic(context, ptr, len);
            pos += len;
        }
        uint64_t current_pos() const override {
            return pos;
        }
        void (*append_diagnostic)(void *, const char *, size_t);
        void *context;
        size_t pos;
};


bool ZigLLDLink(ZigLLVM_ObjectFormatType oformat, const char **args, size_t arg_count,
        void (*append_diagnostic)(void *, const char *, size_t), void *context)
{
    ArrayRef<const char *> array_ref_args(args, arg_count);

    MyOStream diag(append_diagnostic, context);

    switch (oformat) {
        case ZigLLVM_UnknownObjectFormat:
            assert(false); // unreachable

        case ZigLLVM_COFF:
            return lld::coff::link(array_ref_args, false, diag);

        case ZigLLVM_ELF:
            return lld::elf::link(array_ref_args, false, diag);

        case ZigLLVM_MachO:
            return lld::mach_o::link(array_ref_args, diag);

        case ZigLLVM_Wasm:
            return lld::wasm::link(array_ref_args, false, diag);
    }
    assert(false); // unreachable
    abort();
}