slang_rs_backend.cpp revision 1ebc0ca6ffa7effb875883d18205ed4943ab8fc2 
1#include <vector>
2#include <string>
3
4#include "slang_rs_backend.hpp"
5#include "slang_rs_context.hpp"
6#include "slang_rs_export_var.hpp"
7#include "slang_rs_export_func.hpp"
8#include "slang_rs_export_type.hpp"
9
10#include "llvm/Metadata.h"          /* for class llvm::NamedMDNode */
11#include "llvm/ADT/Twine.h"         /* for class llvm::Twine */
12
13#include "clang/AST/DeclGroup.h"    /* for class clang::DeclGroup */
14#include "llvm/ADT/StringExtras.h"  /* for function llvm::utostr_32() and llvm::itostr() */
15
16#include "llvm/Support/IRBuilder.h" /* for class llvm::IRBuilder */
17#include "llvm/Constant.h"          /* for class llvm::Constant */
18#include "llvm/Constants.h"          /* for class llvm::Constant* */
19#include "llvm/Module.h"            /* for class llvm::Module */
20#include "llvm/Function.h"          /* for class llvm::Function */
21#include "llvm/DerivedTypes.h"      /* for class llvm::*Type */
22
23#define MAKE
24
25namespace slang {
26
27RSBackend::RSBackend(RSContext* Context,
28                     Diagnostic &Diags,
29                     const CodeGenOptions& CodeGenOpts,
30                     const TargetOptions& TargetOpts,
31                     const PragmaList& Pragmas,
32                     llvm::raw_ostream* OS,
33                     SlangCompilerOutputTy OutputType,
34                     SourceManager& SourceMgr,
35                     bool AllowRSPrefix) :
36    mContext(Context),
37    Backend(Diags,
38            CodeGenOpts,
39            TargetOpts,
40            Pragmas,
41            OS,
42            OutputType,
43            SourceMgr,
44            AllowRSPrefix),
45    mExportVarMetadata(NULL),
46    mExportFuncMetadata(NULL),
47    mExportTypeMetadata(NULL)
48{
49    return;
50}
51
52void RSBackend::HandleTopLevelDecl(DeclGroupRef D) {
53    Backend::HandleTopLevelDecl(D);
54    return;
55}
56
57void RSBackend::HandleTranslationUnitEx(ASTContext& Ctx) {
58    assert((&Ctx == mContext->getASTContext()) && "Unexpected AST context change during LLVM IR generation");
59    mContext->processExport();
60
61    /* Dump export variable info */
62    if(mContext->hasExportVar()) {
63        if(mExportVarMetadata == NULL)
64            mExportVarMetadata = mpModule->getOrInsertNamedMetadata("#rs_export_var");
65
66        llvm::SmallVector<llvm::Value*, 2> ExportVarInfo;
67
68        for(RSContext::const_export_var_iterator I = mContext->export_vars_begin();
69            I != mContext->export_vars_end();
70            I++)
71        {
72            const RSExportVar* EV = *I;
73            const RSExportType* ET = EV->getType();
74
75            /* variable name */
76            ExportVarInfo.push_back( llvm::MDString::get(mLLVMContext, EV->getName().c_str()) );
77
78            /* type name */
79            if(ET->getClass() == RSExportType::ExportClassPrimitive)
80                ExportVarInfo.push_back( llvm::MDString::get(mLLVMContext, llvm::utostr_32(static_cast<const RSExportPrimitiveType*>(ET)->getType())) );
81            else if(ET->getClass() == RSExportType::ExportClassPointer)
82                ExportVarInfo.push_back( llvm::MDString::get(mLLVMContext, ("*" + static_cast<const RSExportPointerType*>(ET)->getPointeeType()->getName()).c_str()) );
83            else
84                ExportVarInfo.push_back( llvm::MDString::get(mLLVMContext, EV->getType()->getName().c_str()) );
85
86            mExportVarMetadata->addOperand( llvm::MDNode::get(mLLVMContext, ExportVarInfo.data(), ExportVarInfo.size()) );
87
88            ExportVarInfo.clear();
89        }
90    }
91
92    /* Dump export function info */
93    if(mContext->hasExportFunc()) {
94        if(mExportFuncMetadata == NULL)
95            mExportFuncMetadata = mpModule->getOrInsertNamedMetadata("#rs_export_func");
96
97        llvm::SmallVector<llvm::Value*, 1> ExportFuncInfo;
98
99        for(RSContext::const_export_func_iterator I = mContext->export_funcs_begin();
100            I != mContext->export_funcs_end();
101            I++)
102        {
103            const RSExportFunc* EF = *I;
104
105            /* function name */
106            if(!EF->hasParam())
107                ExportFuncInfo.push_back( llvm::MDString::get(mLLVMContext, EF->getName().c_str()) );
108            else {
109                llvm::Function* F = mpModule->getFunction(EF->getName());
110                llvm::Function* HelperFunction;
111                const std::string HelperFunctionName(".helper_" + EF->getName());
112
113                assert(F && "Function marked as exported disappeared in Bitcode");
114
115                /* Create helper function */
116                {
117                    llvm::PointerType* HelperFunctionParameterTypeP = llvm::PointerType::getUnqual(EF->getParamPacketType()->getLLVMType());
118                    llvm::FunctionType* HelperFunctionType;
119                    std::vector<const llvm::Type*> Params;
120
121                    Params.push_back(HelperFunctionParameterTypeP);
122                    HelperFunctionType = llvm::FunctionType::get(F->getReturnType(), Params, false);
123
124                    HelperFunction = llvm::Function::Create(HelperFunctionType, llvm::GlobalValue::ExternalLinkage, HelperFunctionName, mpModule);
125
126                    HelperFunction->addFnAttr(llvm::Attribute::NoInline);
127                    HelperFunction->setCallingConv(F->getCallingConv());
128
129                    /* Create helper function body */
130                    {
131                        llvm::Argument* HelperFunctionParameter = &(*HelperFunction->arg_begin());
132                        llvm::BasicBlock* BB = llvm::BasicBlock::Create(mLLVMContext, "entry", HelperFunction);
133                        llvm::IRBuilder<>* IB = new llvm::IRBuilder<>(BB);
134                        llvm::SmallVector<llvm::Value*, 6> Params;
135                        llvm::Value* Idx[2];
136
137                        Idx[0] = llvm::ConstantInt::get(llvm::Type::getInt32Ty(mLLVMContext), 0);
138
139                        /* getelementptr and load instruction for all elements in parameter .p */
140                        int i;
141                        for (i=0; i < EF->getNumParameters(); i++) {
142
143                          /* getelementptr */
144                          Idx[1] = llvm::ConstantInt::get(llvm::Type::getInt32Ty(mLLVMContext), i);
145                          llvm::Value* Ptr = IB->CreateInBoundsGEP(HelperFunctionParameter, Idx, Idx + 2);
146
147                          /* load */
148                          llvm::Value* V = IB->CreateLoad(Ptr);
149                          Params.push_back(V);
150                        }
151
152                        /* call and pass the all elements as paramter to F */
153                        llvm::CallInst* CI = IB->CreateCall(F, Params.data(), Params.data() + Params.size());
154                        CI->setCallingConv(F->getCallingConv());
155
156                        if(F->getReturnType() == llvm::Type::getVoidTy(mLLVMContext))
157                            IB->CreateRetVoid();
158                        else
159                            IB->CreateRet(CI);
160
161                        delete IB;
162                    }
163                }
164
165                ExportFuncInfo.push_back( llvm::MDString::get(mLLVMContext, HelperFunctionName.c_str()) );
166            }
167
168            mExportFuncMetadata->addOperand( llvm::MDNode::get(mLLVMContext, ExportFuncInfo.data(), ExportFuncInfo.size()) );
169
170            ExportFuncInfo.clear();
171        }
172    }
173
174    /* Dump export type info */
175    if(mContext->hasExportType()) {
176        llvm::SmallVector<llvm::Value*, 1> ExportTypeInfo;
177
178        for(RSContext::const_export_type_iterator I = mContext->export_types_begin();
179            I != mContext->export_types_end();
180            I++)
181        {
182            /* First, dump type name list to export */
183            const RSExportType* ET = I->getValue();
184
185            ExportTypeInfo.clear();
186            /* type name */
187            ExportTypeInfo.push_back( llvm::MDString::get(mLLVMContext, ET->getName().c_str()) );
188
189            if(ET->getClass() == RSExportType::ExportClassRecord) {
190                const RSExportRecordType* ERT = static_cast<const RSExportRecordType*>(ET);
191
192                if(mExportTypeMetadata == NULL)
193                    mExportTypeMetadata = mpModule->getOrInsertNamedMetadata("#rs_export_type");
194
195                mExportTypeMetadata->addOperand( llvm::MDNode::get(mLLVMContext, ExportTypeInfo.data(), ExportTypeInfo.size()) );
196
197                /* Now, export struct field information to %[struct name] */
198                std::string StructInfoMetadataName("%");
199                StructInfoMetadataName.append(ET->getName());
200                llvm::NamedMDNode* StructInfoMetadata = mpModule->getOrInsertNamedMetadata(StructInfoMetadataName);
201                llvm::SmallVector<llvm::Value*, 3> FieldInfo;
202
203                assert(StructInfoMetadata->getNumOperands() == 0 && "Metadata with same name was created before");
204                for(RSExportRecordType::const_field_iterator FI = ERT->fields_begin();
205                    FI != ERT->fields_end();
206                    FI++)
207                {
208                    const RSExportRecordType::Field* F = *FI;
209
210                    /* 1. field name */
211                    FieldInfo.push_back( llvm::MDString::get(mLLVMContext, F->getName().c_str()) );
212                    /* 2. field type name */
213                    FieldInfo.push_back( llvm::MDString::get(mLLVMContext, F->getType()->getName().c_str()) );
214
215                    /* 3. field kind */
216                    switch(F->getType()->getClass()) {
217                        case RSExportType::ExportClassPrimitive:
218                        case RSExportType::ExportClassVector:
219                        {
220                            RSExportPrimitiveType* EPT = (RSExportPrimitiveType*) F->getType();
221                            FieldInfo.push_back( llvm::MDString::get(mLLVMContext, llvm::itostr(EPT->getKind())) );
222                        }
223                        break;
224
225                        default:
226                            FieldInfo.push_back( llvm::MDString::get(mLLVMContext, llvm::itostr(RSExportPrimitiveType::DataKindUser)) );
227                        break;
228                    }
229
230                    StructInfoMetadata->addOperand( llvm::MDNode::get(mLLVMContext, FieldInfo.data(), FieldInfo.size()) );
231
232                    FieldInfo.clear();
233                }
234            }   /* ET->getClass() == RSExportType::ExportClassRecord */
235        }
236    }
237
238    return;
239}
240
241RSBackend::~RSBackend() {
242    return;
243}
244
245}   /* namespace slang */
246