slang_backend.cpp revision 5e306b944425a952fe744f59d828538137a59375
1/*
2 * Copyright 2010-2012, The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "slang_backend.h"
18
19#include <string>
20#include <vector>
21
22#include "clang/AST/ASTContext.h"
23#include "clang/AST/Attr.h"
24#include "clang/AST/Decl.h"
25#include "clang/AST/DeclGroup.h"
26
27#include "clang/Basic/Diagnostic.h"
28#include "clang/Basic/TargetInfo.h"
29#include "clang/Basic/TargetOptions.h"
30
31#include "clang/CodeGen/ModuleBuilder.h"
32
33#include "clang/Frontend/CodeGenOptions.h"
34#include "clang/Frontend/FrontendDiagnostic.h"
35
36#include "llvm/ADT/Twine.h"
37#include "llvm/ADT/StringExtras.h"
38
39#include "llvm/Bitcode/ReaderWriter.h"
40
41#include "llvm/CodeGen/RegAllocRegistry.h"
42#include "llvm/CodeGen/SchedulerRegistry.h"
43
44#include "llvm/IR/Constant.h"
45#include "llvm/IR/Constants.h"
46#include "llvm/IR/DataLayout.h"
47#include "llvm/IR/DebugLoc.h"
48#include "llvm/IR/DerivedTypes.h"
49#include "llvm/IR/Function.h"
50#include "llvm/IR/IRBuilder.h"
51#include "llvm/IR/IRPrintingPasses.h"
52#include "llvm/IR/LLVMContext.h"
53#include "llvm/IR/Metadata.h"
54#include "llvm/IR/Module.h"
55
56#include "llvm/Transforms/IPO/PassManagerBuilder.h"
57
58#include "llvm/Target/TargetMachine.h"
59#include "llvm/Target/TargetOptions.h"
60#include "llvm/Support/TargetRegistry.h"
61
62#include "llvm/MC/SubtargetFeature.h"
63
64#include "slang_assert.h"
65#include "slang.h"
66#include "slang_bitcode_gen.h"
67#include "slang_rs_context.h"
68#include "slang_rs_export_foreach.h"
69#include "slang_rs_export_func.h"
70#include "slang_rs_export_reduce.h"
71#include "slang_rs_export_type.h"
72#include "slang_rs_export_var.h"
73#include "slang_rs_metadata.h"
74
75#include "rs_cc_options.h"
76
77#include "strip_unknown_attributes.h"
78
79namespace slang {
80
81void Backend::CreateFunctionPasses() {
82  if (!mPerFunctionPasses) {
83    mPerFunctionPasses = new llvm::legacy::FunctionPassManager(mpModule);
84
85    llvm::PassManagerBuilder PMBuilder;
86    PMBuilder.OptLevel = mCodeGenOpts.OptimizationLevel;
87    PMBuilder.populateFunctionPassManager(*mPerFunctionPasses);
88  }
89}
90
91void Backend::CreateModulePasses() {
92  if (!mPerModulePasses) {
93    mPerModulePasses = new llvm::legacy::PassManager();
94
95    llvm::PassManagerBuilder PMBuilder;
96    PMBuilder.OptLevel = mCodeGenOpts.OptimizationLevel;
97    PMBuilder.SizeLevel = mCodeGenOpts.OptimizeSize;
98    if (mCodeGenOpts.UnitAtATime) {
99      PMBuilder.DisableUnitAtATime = 0;
100    } else {
101      PMBuilder.DisableUnitAtATime = 1;
102    }
103
104    if (mCodeGenOpts.UnrollLoops) {
105      PMBuilder.DisableUnrollLoops = 0;
106    } else {
107      PMBuilder.DisableUnrollLoops = 1;
108    }
109
110    PMBuilder.populateModulePassManager(*mPerModulePasses);
111    // Add a pass to strip off unknown/unsupported attributes.
112    mPerModulePasses->add(createStripUnknownAttributesPass());
113  }
114}
115
116bool Backend::CreateCodeGenPasses() {
117  if ((mOT != Slang::OT_Assembly) && (mOT != Slang::OT_Object))
118    return true;
119
120  // Now we add passes for code emitting
121  if (mCodeGenPasses) {
122    return true;
123  } else {
124    mCodeGenPasses = new llvm::legacy::FunctionPassManager(mpModule);
125  }
126
127  // Create the TargetMachine for generating code.
128  std::string Triple = mpModule->getTargetTriple();
129
130  std::string Error;
131  const llvm::Target* TargetInfo =
132      llvm::TargetRegistry::lookupTarget(Triple, Error);
133  if (TargetInfo == nullptr) {
134    mDiagEngine.Report(clang::diag::err_fe_unable_to_create_target) << Error;
135    return false;
136  }
137
138  // Target Machine Options
139  llvm::TargetOptions Options;
140
141  // Use soft-float ABI for ARM (which is the target used by Slang during code
142  // generation).  Codegen still uses hardware FPU by default.  To use software
143  // floating point, add 'soft-float' feature to FeaturesStr below.
144  Options.FloatABIType = llvm::FloatABI::Soft;
145
146  // BCC needs all unknown symbols resolved at compilation time. So we don't
147  // need any relocation model.
148  llvm::Reloc::Model RM = llvm::Reloc::Static;
149
150  // This is set for the linker (specify how large of the virtual addresses we
151  // can access for all unknown symbols.)
152  llvm::CodeModel::Model CM;
153  if (mpModule->getDataLayout().getPointerSize() == 4) {
154    CM = llvm::CodeModel::Small;
155  } else {
156    // The target may have pointer size greater than 32 (e.g. x86_64
157    // architecture) may need large data address model
158    CM = llvm::CodeModel::Medium;
159  }
160
161  // Setup feature string
162  std::string FeaturesStr;
163  if (mTargetOpts.CPU.size() || mTargetOpts.Features.size()) {
164    llvm::SubtargetFeatures Features;
165
166    for (std::vector<std::string>::const_iterator
167             I = mTargetOpts.Features.begin(), E = mTargetOpts.Features.end();
168         I != E;
169         I++)
170      Features.AddFeature(*I);
171
172    FeaturesStr = Features.getString();
173  }
174
175  llvm::TargetMachine *TM =
176    TargetInfo->createTargetMachine(Triple, mTargetOpts.CPU, FeaturesStr,
177                                    Options, RM, CM);
178
179  // Register scheduler
180  llvm::RegisterScheduler::setDefault(llvm::createDefaultScheduler);
181
182  // Register allocation policy:
183  //  createFastRegisterAllocator: fast but bad quality
184  //  createGreedyRegisterAllocator: not so fast but good quality
185  llvm::RegisterRegAlloc::setDefault((mCodeGenOpts.OptimizationLevel == 0) ?
186                                     llvm::createFastRegisterAllocator :
187                                     llvm::createGreedyRegisterAllocator);
188
189  llvm::CodeGenOpt::Level OptLevel = llvm::CodeGenOpt::Default;
190  if (mCodeGenOpts.OptimizationLevel == 0) {
191    OptLevel = llvm::CodeGenOpt::None;
192  } else if (mCodeGenOpts.OptimizationLevel == 3) {
193    OptLevel = llvm::CodeGenOpt::Aggressive;
194  }
195
196  llvm::TargetMachine::CodeGenFileType CGFT =
197      llvm::TargetMachine::CGFT_AssemblyFile;
198  if (mOT == Slang::OT_Object) {
199    CGFT = llvm::TargetMachine::CGFT_ObjectFile;
200  }
201  if (TM->addPassesToEmitFile(*mCodeGenPasses, mBufferOutStream,
202                              CGFT, OptLevel)) {
203    mDiagEngine.Report(clang::diag::err_fe_unable_to_interface_with_target);
204    return false;
205  }
206
207  return true;
208}
209
210Backend::Backend(RSContext *Context, clang::DiagnosticsEngine *DiagEngine,
211                 const RSCCOptions &Opts, const clang::CodeGenOptions &CodeGenOpts,
212                 const clang::TargetOptions &TargetOpts, PragmaList *Pragmas,
213                 llvm::raw_ostream *OS, Slang::OutputType OT,
214                 clang::SourceManager &SourceMgr, bool AllowRSPrefix,
215                 bool IsFilterscript)
216    : ASTConsumer(), mTargetOpts(TargetOpts), mpModule(nullptr), mpOS(OS),
217      mOT(OT), mGen(nullptr), mPerFunctionPasses(nullptr),
218      mPerModulePasses(nullptr), mCodeGenPasses(nullptr),
219      mBufferOutStream(*mpOS), mContext(Context),
220      mSourceMgr(SourceMgr), mASTPrint(Opts.mASTPrint), mAllowRSPrefix(AllowRSPrefix),
221      mIsFilterscript(IsFilterscript), mExportVarMetadata(nullptr),
222      mExportFuncMetadata(nullptr), mExportForEachNameMetadata(nullptr),
223      mExportForEachSignatureMetadata(nullptr),
224      mExportReduceNewMetadata(nullptr),
225      mExportTypeMetadata(nullptr), mRSObjectSlotsMetadata(nullptr),
226      mRefCount(mContext->getASTContext()),
227      mASTChecker(Context, Context->getTargetAPI(), IsFilterscript),
228      mForEachHandler(Context),
229      mLLVMContext(llvm::getGlobalContext()), mDiagEngine(*DiagEngine),
230      mCodeGenOpts(CodeGenOpts), mPragmas(Pragmas) {
231  mGen = CreateLLVMCodeGen(mDiagEngine, "", mCodeGenOpts, mLLVMContext);
232}
233
234void Backend::Initialize(clang::ASTContext &Ctx) {
235  mGen->Initialize(Ctx);
236
237  mpModule = mGen->GetModule();
238}
239
240void Backend::HandleTranslationUnit(clang::ASTContext &Ctx) {
241  HandleTranslationUnitPre(Ctx);
242
243  if (mASTPrint)
244    Ctx.getTranslationUnitDecl()->dump();
245
246  mGen->HandleTranslationUnit(Ctx);
247
248  // Here, we complete a translation unit (whole translation unit is now in LLVM
249  // IR). Now, interact with LLVM backend to generate actual machine code (asm
250  // or machine code, whatever.)
251
252  // Silently ignore if we weren't initialized for some reason.
253  if (!mpModule)
254    return;
255
256  llvm::Module *M = mGen->ReleaseModule();
257  if (!M) {
258    // The module has been released by IR gen on failures, do not double free.
259    mpModule = nullptr;
260    return;
261  }
262
263  slangAssert(mpModule == M &&
264              "Unexpected module change during LLVM IR generation");
265
266  // Insert #pragma information into metadata section of module
267  if (!mPragmas->empty()) {
268    llvm::NamedMDNode *PragmaMetadata =
269        mpModule->getOrInsertNamedMetadata(Slang::PragmaMetadataName);
270    for (PragmaList::const_iterator I = mPragmas->begin(), E = mPragmas->end();
271         I != E;
272         I++) {
273      llvm::SmallVector<llvm::Metadata*, 2> Pragma;
274      // Name goes first
275      Pragma.push_back(llvm::MDString::get(mLLVMContext, I->first));
276      // And then value
277      Pragma.push_back(llvm::MDString::get(mLLVMContext, I->second));
278
279      // Create MDNode and insert into PragmaMetadata
280      PragmaMetadata->addOperand(
281          llvm::MDNode::get(mLLVMContext, Pragma));
282    }
283  }
284
285  HandleTranslationUnitPost(mpModule);
286
287  // Create passes for optimization and code emission
288
289  // Create and run per-function passes
290  CreateFunctionPasses();
291  if (mPerFunctionPasses) {
292    mPerFunctionPasses->doInitialization();
293
294    for (llvm::Module::iterator I = mpModule->begin(), E = mpModule->end();
295         I != E;
296         I++)
297      if (!I->isDeclaration())
298        mPerFunctionPasses->run(*I);
299
300    mPerFunctionPasses->doFinalization();
301  }
302
303  // Create and run module passes
304  CreateModulePasses();
305  if (mPerModulePasses)
306    mPerModulePasses->run(*mpModule);
307
308  switch (mOT) {
309    case Slang::OT_Assembly:
310    case Slang::OT_Object: {
311      if (!CreateCodeGenPasses())
312        return;
313
314      mCodeGenPasses->doInitialization();
315
316      for (llvm::Module::iterator I = mpModule->begin(), E = mpModule->end();
317          I != E;
318          I++)
319        if (!I->isDeclaration())
320          mCodeGenPasses->run(*I);
321
322      mCodeGenPasses->doFinalization();
323      break;
324    }
325    case Slang::OT_LLVMAssembly: {
326      llvm::legacy::PassManager *LLEmitPM = new llvm::legacy::PassManager();
327      LLEmitPM->add(llvm::createPrintModulePass(mBufferOutStream));
328      LLEmitPM->run(*mpModule);
329      break;
330    }
331    case Slang::OT_Bitcode: {
332      writeBitcode(mBufferOutStream, *mpModule, getTargetAPI(),
333                   mCodeGenOpts.OptimizationLevel, mCodeGenOpts.getDebugInfo());
334      break;
335    }
336    case Slang::OT_Nothing: {
337      return;
338    }
339    default: {
340      slangAssert(false && "Unknown output type");
341    }
342  }
343
344  mBufferOutStream.flush();
345}
346
347void Backend::HandleTagDeclDefinition(clang::TagDecl *D) {
348  mGen->HandleTagDeclDefinition(D);
349}
350
351void Backend::CompleteTentativeDefinition(clang::VarDecl *D) {
352  mGen->CompleteTentativeDefinition(D);
353}
354
355Backend::~Backend() {
356  delete mpModule;
357  delete mGen;
358  delete mPerFunctionPasses;
359  delete mPerModulePasses;
360  delete mCodeGenPasses;
361}
362
363// 1) Add zero initialization of local RS object types
364void Backend::AnnotateFunction(clang::FunctionDecl *FD) {
365  if (FD &&
366      FD->hasBody() &&
367      !Slang::IsLocInRSHeaderFile(FD->getLocation(), mSourceMgr)) {
368    mRefCount.Init();
369    mRefCount.Visit(FD->getBody());
370  }
371}
372
373void Backend::LowerRSForEachCall(clang::FunctionDecl *FD) {
374  // Skip this AST walking for lower API levels.
375  if (getTargetAPI() < SLANG_N_TARGET_API) {
376    return;
377  }
378
379  if (!FD || !FD->hasBody() ||
380      Slang::IsLocInRSHeaderFile(FD->getLocation(), mSourceMgr)) {
381    return;
382  }
383
384  mForEachHandler.VisitStmt(FD->getBody());
385}
386
387bool Backend::HandleTopLevelDecl(clang::DeclGroupRef D) {
388  // Find and remember the types for rs_allocation and rs_script_call_t so
389  // they can be used later for translating rsForEach() calls.
390  for (clang::DeclGroupRef::iterator I = D.begin(), E = D.end();
391       (mContext->getAllocationType().isNull() ||
392        mContext->getScriptCallType().isNull()) &&
393       I != E; I++) {
394    if (clang::TypeDecl* TD = llvm::dyn_cast<clang::TypeDecl>(*I)) {
395      clang::StringRef TypeName = TD->getName();
396      if (TypeName.equals("rs_allocation")) {
397        mContext->setAllocationType(TD);
398      } else if (TypeName.equals("rs_script_call_t")) {
399        mContext->setScriptCallType(TD);
400      }
401    }
402  }
403
404  // Disallow user-defined functions with prefix "rs"
405  if (!mAllowRSPrefix) {
406    // Iterate all function declarations in the program.
407    for (clang::DeclGroupRef::iterator I = D.begin(), E = D.end();
408         I != E; I++) {
409      clang::FunctionDecl *FD = llvm::dyn_cast<clang::FunctionDecl>(*I);
410      if (FD == nullptr)
411        continue;
412      if (!FD->getName().startswith("rs"))  // Check prefix
413        continue;
414      if (!Slang::IsLocInRSHeaderFile(FD->getLocation(), mSourceMgr))
415        mContext->ReportError(FD->getLocation(),
416                              "invalid function name prefix, "
417                              "\"rs\" is reserved: '%0'")
418            << FD->getName();
419    }
420  }
421
422  for (clang::DeclGroupRef::iterator I = D.begin(), E = D.end(); I != E; I++) {
423    clang::FunctionDecl *FD = llvm::dyn_cast<clang::FunctionDecl>(*I);
424    if (FD) {
425      // Handle forward reference from pragma (see
426      // RSReducePragmaHandler::HandlePragma for backward reference).
427      mContext->markUsedByReducePragma(FD, RSContext::CheckNameYes);
428      if (FD->isGlobal()) {
429        // Check that we don't have any array parameters being misinterpreted as
430        // kernel pointers due to the C type system's array to pointer decay.
431        size_t numParams = FD->getNumParams();
432        for (size_t i = 0; i < numParams; i++) {
433          const clang::ParmVarDecl *PVD = FD->getParamDecl(i);
434          clang::QualType QT = PVD->getOriginalType();
435          if (QT->isArrayType()) {
436            mContext->ReportError(
437                PVD->getTypeSpecStartLoc(),
438                "exported function parameters may not have array type: %0")
439                << QT;
440          }
441        }
442        AnnotateFunction(FD);
443      }
444    }
445
446    if (getTargetAPI() >= SLANG_N_TARGET_API) {
447      if (FD && FD->hasBody() &&
448          RSExportForEach::isRSForEachFunc(getTargetAPI(), FD)) {
449        // Log kernels by their names, and assign them slot numbers.
450        if (!Slang::IsLocInRSHeaderFile(FD->getLocation(), mSourceMgr)) {
451            mContext->addForEach(FD);
452        }
453      } else {
454        // Look for any kernel launch calls and translate them into using the
455        // internal API.
456        // TODO: Simply ignores kernel launch inside a kernel for now.
457        // Needs more rigorous and comprehensive checks.
458        LowerRSForEachCall(FD);
459      }
460    }
461  }
462
463  return mGen->HandleTopLevelDecl(D);
464}
465
466void Backend::HandleTranslationUnitPre(clang::ASTContext &C) {
467  clang::TranslationUnitDecl *TUDecl = C.getTranslationUnitDecl();
468
469  if (!mContext->processReducePragmas(this))
470    return;
471
472  // If we have an invalid RS/FS AST, don't check further.
473  if (!mASTChecker.Validate()) {
474    return;
475  }
476
477  if (mIsFilterscript) {
478    mContext->addPragma("rs_fp_relaxed", "");
479  }
480
481  int version = mContext->getVersion();
482  if (version == 0) {
483    // Not setting a version is an error
484    mDiagEngine.Report(
485        mSourceMgr.getLocForEndOfFile(mSourceMgr.getMainFileID()),
486        mDiagEngine.getCustomDiagID(
487            clang::DiagnosticsEngine::Error,
488            "missing pragma for version in source file"));
489  } else {
490    slangAssert(version == 1);
491  }
492
493  if (mContext->getReflectJavaPackageName().empty()) {
494    mDiagEngine.Report(
495        mSourceMgr.getLocForEndOfFile(mSourceMgr.getMainFileID()),
496        mDiagEngine.getCustomDiagID(clang::DiagnosticsEngine::Error,
497                                    "missing \"#pragma rs "
498                                    "java_package_name(com.foo.bar)\" "
499                                    "in source file"));
500    return;
501  }
502
503  // Create a static global destructor if necessary (to handle RS object
504  // runtime cleanup).
505  clang::FunctionDecl *FD = mRefCount.CreateStaticGlobalDtor();
506  if (FD) {
507    HandleTopLevelDecl(clang::DeclGroupRef(FD));
508  }
509
510  // Process any static function declarations
511  for (clang::DeclContext::decl_iterator I = TUDecl->decls_begin(),
512          E = TUDecl->decls_end(); I != E; I++) {
513    if ((I->getKind() >= clang::Decl::firstFunction) &&
514        (I->getKind() <= clang::Decl::lastFunction)) {
515      clang::FunctionDecl *FD = llvm::dyn_cast<clang::FunctionDecl>(*I);
516      if (FD && !FD->isGlobal()) {
517        AnnotateFunction(FD);
518      }
519    }
520  }
521}
522
523///////////////////////////////////////////////////////////////////////////////
524void Backend::dumpExportVarInfo(llvm::Module *M) {
525  int slotCount = 0;
526  if (mExportVarMetadata == nullptr)
527    mExportVarMetadata = M->getOrInsertNamedMetadata(RS_EXPORT_VAR_MN);
528
529  llvm::SmallVector<llvm::Metadata *, 2> ExportVarInfo;
530
531  // We emit slot information (#rs_object_slots) for any reference counted
532  // RS type or pointer (which can also be bound).
533
534  for (RSContext::const_export_var_iterator I = mContext->export_vars_begin(),
535          E = mContext->export_vars_end();
536       I != E;
537       I++) {
538    const RSExportVar *EV = *I;
539    const RSExportType *ET = EV->getType();
540    bool countsAsRSObject = false;
541
542    // Variable name
543    ExportVarInfo.push_back(
544        llvm::MDString::get(mLLVMContext, EV->getName().c_str()));
545
546    // Type name
547    switch (ET->getClass()) {
548      case RSExportType::ExportClassPrimitive: {
549        const RSExportPrimitiveType *PT =
550            static_cast<const RSExportPrimitiveType*>(ET);
551        ExportVarInfo.push_back(
552            llvm::MDString::get(
553              mLLVMContext, llvm::utostr_32(PT->getType())));
554        if (PT->isRSObjectType()) {
555          countsAsRSObject = true;
556        }
557        break;
558      }
559      case RSExportType::ExportClassPointer: {
560        ExportVarInfo.push_back(
561            llvm::MDString::get(
562              mLLVMContext, ("*" + static_cast<const RSExportPointerType*>(ET)
563                ->getPointeeType()->getName()).c_str()));
564        break;
565      }
566      case RSExportType::ExportClassMatrix: {
567        ExportVarInfo.push_back(
568            llvm::MDString::get(
569              mLLVMContext, llvm::utostr_32(
570                  /* TODO Strange value.  This pushes just a number, quite
571                   * different than the other cases.  What is this used for?
572                   * These are the metadata values that some partner drivers
573                   * want to reference (for TBAA, etc.). We may want to look
574                   * at whether these provide any reasonable value (or have
575                   * distinct enough values to actually depend on).
576                   */
577                DataTypeRSMatrix2x2 +
578                static_cast<const RSExportMatrixType*>(ET)->getDim() - 2)));
579        break;
580      }
581      case RSExportType::ExportClassVector:
582      case RSExportType::ExportClassConstantArray:
583      case RSExportType::ExportClassRecord: {
584        ExportVarInfo.push_back(
585            llvm::MDString::get(mLLVMContext,
586              EV->getType()->getName().c_str()));
587        break;
588      }
589    }
590
591    mExportVarMetadata->addOperand(
592        llvm::MDNode::get(mLLVMContext, ExportVarInfo));
593    ExportVarInfo.clear();
594
595    if (mRSObjectSlotsMetadata == nullptr) {
596      mRSObjectSlotsMetadata =
597          M->getOrInsertNamedMetadata(RS_OBJECT_SLOTS_MN);
598    }
599
600    if (countsAsRSObject) {
601      mRSObjectSlotsMetadata->addOperand(llvm::MDNode::get(mLLVMContext,
602          llvm::MDString::get(mLLVMContext, llvm::utostr_32(slotCount))));
603    }
604
605    slotCount++;
606  }
607}
608
609void Backend::dumpExportFunctionInfo(llvm::Module *M) {
610  if (mExportFuncMetadata == nullptr)
611    mExportFuncMetadata =
612        M->getOrInsertNamedMetadata(RS_EXPORT_FUNC_MN);
613
614  llvm::SmallVector<llvm::Metadata *, 1> ExportFuncInfo;
615
616  for (RSContext::const_export_func_iterator
617          I = mContext->export_funcs_begin(),
618          E = mContext->export_funcs_end();
619       I != E;
620       I++) {
621    const RSExportFunc *EF = *I;
622
623    // Function name
624    if (!EF->hasParam()) {
625      ExportFuncInfo.push_back(llvm::MDString::get(mLLVMContext,
626                                                   EF->getName().c_str()));
627    } else {
628      llvm::Function *F = M->getFunction(EF->getName());
629      llvm::Function *HelperFunction;
630      const std::string HelperFunctionName(".helper_" + EF->getName());
631
632      slangAssert(F && "Function marked as exported disappeared in Bitcode");
633
634      // Create helper function
635      {
636        llvm::StructType *HelperFunctionParameterTy = nullptr;
637        std::vector<bool> isStructInput;
638
639        if (!F->getArgumentList().empty()) {
640          std::vector<llvm::Type*> HelperFunctionParameterTys;
641          for (llvm::Function::arg_iterator AI = F->arg_begin(),
642                   AE = F->arg_end(); AI != AE; AI++) {
643              if (AI->getType()->isPointerTy() && AI->getType()->getPointerElementType()->isStructTy()) {
644                  HelperFunctionParameterTys.push_back(AI->getType()->getPointerElementType());
645                  isStructInput.push_back(true);
646              } else {
647                  HelperFunctionParameterTys.push_back(AI->getType());
648                  isStructInput.push_back(false);
649              }
650          }
651          HelperFunctionParameterTy =
652              llvm::StructType::get(mLLVMContext, HelperFunctionParameterTys);
653        }
654
655        if (!EF->checkParameterPacketType(HelperFunctionParameterTy)) {
656          fprintf(stderr, "Failed to export function %s: parameter type "
657                          "mismatch during creation of helper function.\n",
658                  EF->getName().c_str());
659
660          const RSExportRecordType *Expected = EF->getParamPacketType();
661          if (Expected) {
662            fprintf(stderr, "Expected:\n");
663            Expected->getLLVMType()->dump();
664          }
665          if (HelperFunctionParameterTy) {
666            fprintf(stderr, "Got:\n");
667            HelperFunctionParameterTy->dump();
668          }
669        }
670
671        std::vector<llvm::Type*> Params;
672        if (HelperFunctionParameterTy) {
673          llvm::PointerType *HelperFunctionParameterTyP =
674              llvm::PointerType::getUnqual(HelperFunctionParameterTy);
675          Params.push_back(HelperFunctionParameterTyP);
676        }
677
678        llvm::FunctionType * HelperFunctionType =
679            llvm::FunctionType::get(F->getReturnType(),
680                                    Params,
681                                    /* IsVarArgs = */false);
682
683        HelperFunction =
684            llvm::Function::Create(HelperFunctionType,
685                                   llvm::GlobalValue::ExternalLinkage,
686                                   HelperFunctionName,
687                                   M);
688
689        HelperFunction->addFnAttr(llvm::Attribute::NoInline);
690        HelperFunction->setCallingConv(F->getCallingConv());
691
692        // Create helper function body
693        {
694          llvm::Argument *HelperFunctionParameter =
695              &(*HelperFunction->arg_begin());
696          llvm::BasicBlock *BB =
697              llvm::BasicBlock::Create(mLLVMContext, "entry", HelperFunction);
698          llvm::IRBuilder<> *IB = new llvm::IRBuilder<>(BB);
699          llvm::SmallVector<llvm::Value*, 6> Params;
700          llvm::Value *Idx[2];
701
702          Idx[0] =
703              llvm::ConstantInt::get(llvm::Type::getInt32Ty(mLLVMContext), 0);
704
705          // getelementptr and load instruction for all elements in
706          // parameter .p
707          for (size_t i = 0; i < EF->getNumParameters(); i++) {
708            // getelementptr
709            Idx[1] = llvm::ConstantInt::get(
710              llvm::Type::getInt32Ty(mLLVMContext), i);
711
712            llvm::Value *Ptr = NULL;
713
714            Ptr = IB->CreateInBoundsGEP(HelperFunctionParameter, Idx);
715
716            // Load is only required for non-struct ptrs
717            if (isStructInput[i]) {
718                Params.push_back(Ptr);
719            } else {
720                llvm::Value *V = IB->CreateLoad(Ptr);
721                Params.push_back(V);
722            }
723          }
724
725          // Call and pass the all elements as parameter to F
726          llvm::CallInst *CI = IB->CreateCall(F, Params);
727
728          CI->setCallingConv(F->getCallingConv());
729
730          if (F->getReturnType() == llvm::Type::getVoidTy(mLLVMContext)) {
731            IB->CreateRetVoid();
732          } else {
733            IB->CreateRet(CI);
734          }
735
736          delete IB;
737        }
738      }
739
740      ExportFuncInfo.push_back(
741          llvm::MDString::get(mLLVMContext, HelperFunctionName.c_str()));
742    }
743
744    mExportFuncMetadata->addOperand(
745        llvm::MDNode::get(mLLVMContext, ExportFuncInfo));
746    ExportFuncInfo.clear();
747  }
748}
749
750void Backend::dumpExportForEachInfo(llvm::Module *M) {
751  if (mExportForEachNameMetadata == nullptr) {
752    mExportForEachNameMetadata =
753        M->getOrInsertNamedMetadata(RS_EXPORT_FOREACH_NAME_MN);
754  }
755  if (mExportForEachSignatureMetadata == nullptr) {
756    mExportForEachSignatureMetadata =
757        M->getOrInsertNamedMetadata(RS_EXPORT_FOREACH_MN);
758  }
759
760  llvm::SmallVector<llvm::Metadata *, 1> ExportForEachName;
761  llvm::SmallVector<llvm::Metadata *, 1> ExportForEachInfo;
762
763  for (RSContext::const_export_foreach_iterator
764          I = mContext->export_foreach_begin(),
765          E = mContext->export_foreach_end();
766       I != E;
767       I++) {
768    const RSExportForEach *EFE = *I;
769
770    ExportForEachName.push_back(
771        llvm::MDString::get(mLLVMContext, EFE->getName().c_str()));
772
773    mExportForEachNameMetadata->addOperand(
774        llvm::MDNode::get(mLLVMContext, ExportForEachName));
775    ExportForEachName.clear();
776
777    ExportForEachInfo.push_back(
778        llvm::MDString::get(mLLVMContext,
779                            llvm::utostr_32(EFE->getSignatureMetadata())));
780
781    mExportForEachSignatureMetadata->addOperand(
782        llvm::MDNode::get(mLLVMContext, ExportForEachInfo));
783    ExportForEachInfo.clear();
784  }
785}
786
787void Backend::dumpExportReduceNewInfo(llvm::Module *M) {
788  if (!mExportReduceNewMetadata) {
789    mExportReduceNewMetadata =
790      M->getOrInsertNamedMetadata(RS_EXPORT_REDUCE_NEW_MN);
791  }
792
793  llvm::SmallVector<llvm::Metadata *, 6> ExportReduceNewInfo;
794  // Add operand to ExportReduceNewInfo, padding out missing operands with
795  // nullptr.
796  auto addOperand = [&ExportReduceNewInfo](uint32_t Idx, llvm::Metadata *N) {
797    while (Idx > ExportReduceNewInfo.size())
798      ExportReduceNewInfo.push_back(nullptr);
799    ExportReduceNewInfo.push_back(N);
800  };
801  // Add string operand to ExportReduceNewInfo, padding out missing operands
802  // with nullptr.
803  // If string is empty, then do not add it unless Always is true.
804  auto addString = [&addOperand, this](uint32_t Idx, const std::string &S,
805                                       bool Always = true) {
806    if (Always || !S.empty())
807      addOperand(Idx, llvm::MDString::get(mLLVMContext, S));
808  };
809
810  // Add the description of the reduction kernels to the metadata node.
811  for (auto I = mContext->export_reduce_new_begin(),
812            E = mContext->export_reduce_new_end();
813       I != E; ++I) {
814    ExportReduceNewInfo.clear();
815
816    int Idx = 0;
817
818    addString(Idx++, (*I)->getNameReduce());
819
820    addOperand(Idx++, llvm::MDString::get(mLLVMContext, llvm::utostr_32((*I)->getAccumulatorTypeSize())));
821
822    llvm::SmallVector<llvm::Metadata *, 2> Accumulator;
823    Accumulator.push_back(
824      llvm::MDString::get(mLLVMContext, (*I)->getNameAccumulator()));
825    Accumulator.push_back(llvm::MDString::get(
826      mLLVMContext,
827      llvm::utostr_32((*I)->getAccumulatorSignatureMetadata())));
828    addOperand(Idx++, llvm::MDTuple::get(mLLVMContext, Accumulator));
829
830    addString(Idx++, (*I)->getNameInitializer(), false);
831    addString(Idx++, (*I)->getNameCombiner(), false);
832    addString(Idx++, (*I)->getNameOutConverter(), false);
833    addString(Idx++, (*I)->getNameHalter(), false);
834
835    mExportReduceNewMetadata->addOperand(
836      llvm::MDTuple::get(mLLVMContext, ExportReduceNewInfo));
837  }
838}
839
840void Backend::dumpExportTypeInfo(llvm::Module *M) {
841  llvm::SmallVector<llvm::Metadata *, 1> ExportTypeInfo;
842
843  for (RSContext::const_export_type_iterator
844          I = mContext->export_types_begin(),
845          E = mContext->export_types_end();
846       I != E;
847       I++) {
848    // First, dump type name list to export
849    const RSExportType *ET = I->getValue();
850
851    ExportTypeInfo.clear();
852    // Type name
853    ExportTypeInfo.push_back(
854        llvm::MDString::get(mLLVMContext, ET->getName().c_str()));
855
856    if (ET->getClass() == RSExportType::ExportClassRecord) {
857      const RSExportRecordType *ERT =
858          static_cast<const RSExportRecordType*>(ET);
859
860      if (mExportTypeMetadata == nullptr)
861        mExportTypeMetadata =
862            M->getOrInsertNamedMetadata(RS_EXPORT_TYPE_MN);
863
864      mExportTypeMetadata->addOperand(
865          llvm::MDNode::get(mLLVMContext, ExportTypeInfo));
866
867      // Now, export struct field information to %[struct name]
868      std::string StructInfoMetadataName("%");
869      StructInfoMetadataName.append(ET->getName());
870      llvm::NamedMDNode *StructInfoMetadata =
871          M->getOrInsertNamedMetadata(StructInfoMetadataName);
872      llvm::SmallVector<llvm::Metadata *, 3> FieldInfo;
873
874      slangAssert(StructInfoMetadata->getNumOperands() == 0 &&
875                  "Metadata with same name was created before");
876      for (RSExportRecordType::const_field_iterator FI = ERT->fields_begin(),
877              FE = ERT->fields_end();
878           FI != FE;
879           FI++) {
880        const RSExportRecordType::Field *F = *FI;
881
882        // 1. field name
883        FieldInfo.push_back(llvm::MDString::get(mLLVMContext,
884                                                F->getName().c_str()));
885
886        // 2. field type name
887        FieldInfo.push_back(
888            llvm::MDString::get(mLLVMContext,
889                                F->getType()->getName().c_str()));
890
891        StructInfoMetadata->addOperand(
892            llvm::MDNode::get(mLLVMContext, FieldInfo));
893        FieldInfo.clear();
894      }
895    }   // ET->getClass() == RSExportType::ExportClassRecord
896  }
897}
898
899void Backend::HandleTranslationUnitPost(llvm::Module *M) {
900
901  if (!mContext->is64Bit()) {
902    M->setDataLayout("e-p:32:32-i64:64-v128:64:128-n32-S64");
903  }
904
905  if (!mContext->processExports())
906    return;
907
908  if (mContext->hasExportVar())
909    dumpExportVarInfo(M);
910
911  if (mContext->hasExportFunc())
912    dumpExportFunctionInfo(M);
913
914  if (mContext->hasExportForEach())
915    dumpExportForEachInfo(M);
916
917  if (mContext->hasExportReduceNew())
918    dumpExportReduceNewInfo(M);
919
920  if (mContext->hasExportType())
921    dumpExportTypeInfo(M);
922}
923
924}  // namespace slang
925