1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
#include "cps/FunctionGen.h"
#include "cps/CodeGen.h"
#include <cstdio>
using namespace llvm;
using namespace cps;
// Symbols the compiler itself declares (libc + runtime); a user
// FUNCTION/PROCEDURE with one of these names would hijack the runtime.
static bool isReservedRuntimeName(const std::string &Name) {
static const char *Reserved[] = {
"main", "printf", "scanf", "malloc", "free", "strlen", "memcpy",
"strcpy", "strcat", "toupper", "tolower", "sprintf", "strtol",
"strtod", "memset", "exit",
"fopen", "fclose", "fgetc", "ungetc", "fputs", "fputc",
"realloc", "strcmp",
};
for (const char *R : Reserved) {
if (Name == R) return true;
}
return false;
}
Type *FunctionGen::getLLVMType(const std::string &TypeName) {
Type *Resolved = Types.getLLVMType(TypeName);
if (!Resolved) {
fprintf(stderr, "Error: Unknown type %s\n", TypeName.c_str());
HadError = true;
return Type::getInt64Ty(Context);
}
return Resolved;
}
void FunctionGen::createArgumentAllocas(Function *F, const std::vector<ParamDecl> &Params) {
Function::arg_iterator AI = F->arg_begin();
for (const ParamDecl &P : Params) {
Value *ArgVal = &(*AI);
++AI;
ArgVal->setName(P.Name);
if (P.Mode == PassMode::ByRef) {
Symbols[P.Name] = {ArgVal, P.TypeName, false};
continue;
}
Type *ArgType = getLLVMType(P.TypeName);
IRBuilder<> TmpB(&F->getEntryBlock(), F->getEntryBlock().begin());
AllocaInst *Alloca = TmpB.CreateAlloca(ArgType, nullptr, P.Name);
Builder.CreateStore(ArgVal, Alloca);
Symbols[P.Name] = {Alloca, P.TypeName, false};
}
}
const FuncSig *FunctionGen::getSignature(const std::string &Name) const {
auto It = Signatures.find(Name);
return It == Signatures.end() ? nullptr : &It->second;
}
Function *FunctionGen::emitPrototype(PrototypeAST *Proto) {
if (isReservedRuntimeName(Proto->getName())) {
fprintf(stderr, "Error: '%s' is a reserved runtime symbol and cannot be a FUNCTION/PROCEDURE name\n",
Proto->getName().c_str());
HadError = true;
return nullptr;
}
if (CodeGen::isBuiltinName(Proto->getName())) {
fprintf(stderr, "Error: '%s' is a built-in function and cannot be redefined\n",
Proto->getName().c_str());
HadError = true;
return nullptr;
}
FuncSig Sig;
Sig.ReturnTypeName = Proto->getReturnType();
std::vector<Type*> ArgTypes;
for (const ParamDecl &P : Proto->getParams()) {
if (P.IsArray) {
fprintf(stderr, "Error: Array parameters are not implemented yet (parameter '%s' of %s)\n",
P.Name.c_str(), Proto->getName().c_str());
HadError = true;
return nullptr;
}
Type *T = getLLVMType(P.TypeName);
if (P.Mode == PassMode::ByRef) {
T = T->getPointerTo();
}
ArgTypes.push_back(T);
Sig.Params.emplace_back(P.TypeName, P.Mode == PassMode::ByRef);
}
Type *RetType = getLLVMType(Proto->getReturnType());
FunctionType *FT = FunctionType::get(RetType, ArgTypes, false);
Function *F = Module.getFunction(Proto->getName());
if (F && F->getFunctionType() != FT) {
fprintf(stderr, "Error: Function %s conflicts with an existing declaration of a different type\n",
Proto->getName().c_str());
HadError = true;
return nullptr;
}
if (!F) {
F = Function::Create(FT, Function::ExternalLinkage, Proto->getName(), &Module);
}
// Keep the first registration: on a duplicate definition the first one
// wins and the second is rejected by emitFunctionDef.
Signatures.emplace(Proto->getName(), std::move(Sig));
unsigned Idx = 0;
for (auto &Arg : F->args()) {
if (Idx < Proto->getParams().size()) {
Arg.setName(Proto->getParams()[Idx++].Name);
}
}
return F;
}
Function *FunctionGen::emitFunctionDef(FunctionDefAST *FuncAST,
const std::function<void(StmtAST*)> &StmtEmitter) {
PrototypeAST *Proto = FuncAST->getProto();
Function *TheFunction = emitPrototype(Proto);
if (!TheFunction) return nullptr;
if (!TheFunction->empty()) {
fprintf(stderr, "Error: Function %s cannot be redefined.\n", Proto->getName().c_str());
HadError = true;
return nullptr;
}
BasicBlock *BB = BasicBlock::Create(Context, "entry", TheFunction);
Builder.SetInsertPoint(BB);
std::map<std::string, SymbolInfo> OldSymbols = Symbols;
Symbols.clear();
createArgumentAllocas(TheFunction, Proto->getParams());
for (const auto &Stmt : FuncAST->getBody()) {
StmtEmitter(Stmt.get());
}
if (!Builder.GetInsertBlock()->getTerminator()) {
if (Proto->getReturnType() == "VOID") {
Builder.CreateRetVoid();
} else {
Builder.CreateRet(Constant::getNullValue(TheFunction->getReturnType()));
}
}
Symbols = OldSymbols;
return TheFunction;
}
static Value *GenerateCall(llvm::Module &Module,
llvm::IRBuilder<> &Builder,
const std::string &CalleeName,
const std::vector<llvm::Value*> &Args,
bool &HadError) {
Function *CalleeF = Module.getFunction(CalleeName);
if (!CalleeF) {
fprintf(stderr, "Error: Call to undefined function %s\n", CalleeName.c_str());
HadError = true;
return nullptr;
}
if (CalleeF->getReturnType()->isVoidTy()) {
return Builder.CreateCall(CalleeF, Args);
}
return Builder.CreateCall(CalleeF, Args, "calltmp");
}
llvm::Value *FunctionGen::emitCallExpr(CallExprAST *Call, const std::vector<llvm::Value*> &Args) {
return GenerateCall(Module, Builder, Call->getCallee(), Args, HadError);
}
void FunctionGen::emitCallStmt(CallStmtAST *Call, const std::vector<llvm::Value*> &Args) {
GenerateCall(Module, Builder, Call->getCallee(), Args, HadError);
}
void FunctionGen::emitReturn(ReturnStmtAST *Ret, llvm::Value *RetVal) {
if (RetVal) {
Builder.CreateRet(RetVal);
} else {
Builder.CreateRetVoid();
}
}
|
