1 //===-- Writer.cpp - Library for converting LLVM code to C ----------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This library converts LLVM code to C code, compilable by GCC and other C
13 //===----------------------------------------------------------------------===//
15 #include "CTargetMachine.h"
16 #include "llvm/Constants.h"
17 #include "llvm/DerivedTypes.h"
18 #include "llvm/Module.h"
19 #include "llvm/Instructions.h"
20 #include "llvm/Pass.h"
21 #include "llvm/PassManager.h"
22 #include "llvm/SymbolTable.h"
23 #include "llvm/Intrinsics.h"
24 #include "llvm/Analysis/ConstantsScanner.h"
25 #include "llvm/Analysis/FindUsedTypes.h"
26 #include "llvm/Analysis/LoopInfo.h"
27 #include "llvm/CodeGen/IntrinsicLowering.h"
28 #include "llvm/Transforms/Scalar.h"
29 #include "llvm/Target/TargetMachineRegistry.h"
30 #include "llvm/Support/CallSite.h"
31 #include "llvm/Support/CFG.h"
32 #include "llvm/Support/GetElementPtrTypeIterator.h"
33 #include "llvm/Support/InstVisitor.h"
34 #include "llvm/Support/Mangler.h"
35 #include "llvm/ADT/StringExtras.h"
36 #include "llvm/Support/MathExtras.h"
37 #include "llvm/Config/config.h"
44 // Register the target.
45 RegisterTarget<CTargetMachine> X("c", " C backend");
47 /// NameAllUsedStructs - This pass inserts names for any unnamed structure
48 /// types that are used by the program.
50 class CBackendNameAllUsedStructs : public ModulePass {
51 void getAnalysisUsage(AnalysisUsage &AU) const {
52 AU.addRequired<FindUsedTypes>();
55 virtual const char *getPassName() const {
56 return "C backend type canonicalizer";
59 virtual bool runOnModule(Module &M);
62 /// CWriter - This class is the main chunk of code that converts an LLVM
63 /// module to a C translation unit.
64 class CWriter : public FunctionPass, public InstVisitor<CWriter> {
66 IntrinsicLowering &IL;
69 const Module *TheModule;
70 std::map<const Type *, std::string> TypeNames;
72 std::map<const ConstantFP *, unsigned> FPConstantMap;
74 CWriter(std::ostream &o, IntrinsicLowering &il) : Out(o), IL(il) {}
76 virtual const char *getPassName() const { return "C backend"; }
78 void getAnalysisUsage(AnalysisUsage &AU) const {
79 AU.addRequired<LoopInfo>();
83 virtual bool doInitialization(Module &M);
85 bool runOnFunction(Function &F) {
86 LI = &getAnalysis<LoopInfo>();
88 // Get rid of intrinsics we can't handle.
91 // Output all floating point constants that cannot be printed accurately.
92 printFloatingPointConstants(F);
94 // Ensure that no local symbols conflict with global symbols.
95 F.renameLocalSymbols();
98 FPConstantMap.clear();
102 virtual bool doFinalization(Module &M) {
109 std::ostream &printType(std::ostream &Out, const Type *Ty,
110 const std::string &VariableName = "",
111 bool IgnoreName = false);
113 void writeOperand(Value *Operand);
114 void writeOperandInternal(Value *Operand);
117 void lowerIntrinsics(Function &F);
119 bool nameAllUsedStructureTypes(Module &M);
120 void printModule(Module *M);
121 void printModuleTypes(const SymbolTable &ST);
122 void printContainedStructs(const Type *Ty, std::set<const StructType *> &);
123 void printFloatingPointConstants(Function &F);
124 void printFunctionSignature(const Function *F, bool Prototype);
126 void printFunction(Function &);
127 void printBasicBlock(BasicBlock *BB);
128 void printLoop(Loop *L);
130 void printConstant(Constant *CPV);
131 void printConstantArray(ConstantArray *CPA);
133 // isInlinableInst - Attempt to inline instructions into their uses to build
134 // trees as much as possible. To do this, we have to consistently decide
135 // what is acceptable to inline, so that variable declarations don't get
136 // printed and an extra copy of the expr is not emitted.
138 static bool isInlinableInst(const Instruction &I) {
139 // Always inline setcc instructions, even if they are shared by multiple
140 // expressions. GCC generates horrible code if we don't.
141 if (isa<SetCondInst>(I)) return true;
143 // Must be an expression, must be used exactly once. If it is dead, we
144 // emit it inline where it would go.
145 if (I.getType() == Type::VoidTy || !I.hasOneUse() ||
146 isa<TerminatorInst>(I) || isa<CallInst>(I) || isa<PHINode>(I) ||
147 isa<LoadInst>(I) || isa<VAArgInst>(I) || isa<VANextInst>(I))
148 // Don't inline a load across a store or other bad things!
151 // Only inline instruction it it's use is in the same BB as the inst.
152 return I.getParent() == cast<Instruction>(I.use_back())->getParent();
155 // isDirectAlloca - Define fixed sized allocas in the entry block as direct
156 // variables which are accessed with the & operator. This causes GCC to
157 // generate significantly better code than to emit alloca calls directly.
159 static const AllocaInst *isDirectAlloca(const Value *V) {
160 const AllocaInst *AI = dyn_cast<AllocaInst>(V);
161 if (!AI) return false;
162 if (AI->isArrayAllocation())
163 return 0; // FIXME: we can also inline fixed size array allocas!
164 if (AI->getParent() != &AI->getParent()->getParent()->getEntryBlock())
169 // Instruction visitation functions
170 friend class InstVisitor<CWriter>;
172 void visitReturnInst(ReturnInst &I);
173 void visitBranchInst(BranchInst &I);
174 void visitSwitchInst(SwitchInst &I);
175 void visitInvokeInst(InvokeInst &I) {
176 assert(0 && "Lowerinvoke pass didn't work!");
179 void visitUnwindInst(UnwindInst &I) {
180 assert(0 && "Lowerinvoke pass didn't work!");
182 void visitUnreachableInst(UnreachableInst &I);
184 void visitPHINode(PHINode &I);
185 void visitBinaryOperator(Instruction &I);
187 void visitCastInst (CastInst &I);
188 void visitSelectInst(SelectInst &I);
189 void visitCallInst (CallInst &I);
190 void visitShiftInst(ShiftInst &I) { visitBinaryOperator(I); }
192 void visitMallocInst(MallocInst &I);
193 void visitAllocaInst(AllocaInst &I);
194 void visitFreeInst (FreeInst &I);
195 void visitLoadInst (LoadInst &I);
196 void visitStoreInst (StoreInst &I);
197 void visitGetElementPtrInst(GetElementPtrInst &I);
198 void visitVANextInst(VANextInst &I);
199 void visitVAArgInst (VAArgInst &I);
201 void visitInstruction(Instruction &I) {
202 std::cerr << "C Writer does not know about " << I;
206 void outputLValue(Instruction *I) {
207 Out << " " << Mang->getValueName(I) << " = ";
210 bool isGotoCodeNecessary(BasicBlock *From, BasicBlock *To);
211 void printPHICopiesForSuccessor(BasicBlock *CurBlock,
212 BasicBlock *Successor, unsigned Indent);
213 void printBranchToBlock(BasicBlock *CurBlock, BasicBlock *SuccBlock,
215 void printIndexingExpression(Value *Ptr, gep_type_iterator I,
216 gep_type_iterator E);
217 void printCodeForMain();
221 /// This method inserts names for any unnamed structure types that are used by
222 /// the program, and removes names from structure types that are not used by the
225 bool CBackendNameAllUsedStructs::runOnModule(Module &M) {
226 // Get a set of types that are used by the program...
227 std::set<const Type *> UT = getAnalysis<FindUsedTypes>().getTypes();
229 // Loop over the module symbol table, removing types from UT that are
230 // already named, and removing names for structure types that are not used.
232 SymbolTable &MST = M.getSymbolTable();
233 for (SymbolTable::type_iterator TI = MST.type_begin(), TE = MST.type_end();
235 SymbolTable::type_iterator I = TI++;
236 if (const StructType *STy = dyn_cast<StructType>(I->second)) {
237 // If this is not used, remove it from the symbol table.
238 std::set<const Type *>::iterator UTI = UT.find(STy);
246 // UT now contains types that are not named. Loop over it, naming
249 bool Changed = false;
250 unsigned RenameCounter = 0;
251 for (std::set<const Type *>::const_iterator I = UT.begin(), E = UT.end();
253 if (const StructType *ST = dyn_cast<StructType>(*I)) {
254 while (M.addTypeName("unnamed"+utostr(RenameCounter), ST))
262 // Pass the Type* and the variable name and this prints out the variable
265 std::ostream &CWriter::printType(std::ostream &Out, const Type *Ty,
266 const std::string &NameSoFar,
268 if (Ty->isPrimitiveType())
269 switch (Ty->getTypeID()) {
270 case Type::VoidTyID: return Out << "void " << NameSoFar;
271 case Type::BoolTyID: return Out << "bool " << NameSoFar;
272 case Type::UByteTyID: return Out << "unsigned char " << NameSoFar;
273 case Type::SByteTyID: return Out << "signed char " << NameSoFar;
274 case Type::UShortTyID: return Out << "unsigned short " << NameSoFar;
275 case Type::ShortTyID: return Out << "short " << NameSoFar;
276 case Type::UIntTyID: return Out << "unsigned " << NameSoFar;
277 case Type::IntTyID: return Out << "int " << NameSoFar;
278 case Type::ULongTyID: return Out << "unsigned long long " << NameSoFar;
279 case Type::LongTyID: return Out << "signed long long " << NameSoFar;
280 case Type::FloatTyID: return Out << "float " << NameSoFar;
281 case Type::DoubleTyID: return Out << "double " << NameSoFar;
283 std::cerr << "Unknown primitive type: " << *Ty << "\n";
287 // Check to see if the type is named.
288 if (!IgnoreName || isa<OpaqueType>(Ty)) {
289 std::map<const Type *, std::string>::iterator I = TypeNames.find(Ty);
290 if (I != TypeNames.end()) return Out << I->second << " " << NameSoFar;
293 switch (Ty->getTypeID()) {
294 case Type::FunctionTyID: {
295 const FunctionType *MTy = cast<FunctionType>(Ty);
296 std::stringstream FunctionInnards;
297 FunctionInnards << " (" << NameSoFar << ") (";
298 for (FunctionType::param_iterator I = MTy->param_begin(),
299 E = MTy->param_end(); I != E; ++I) {
300 if (I != MTy->param_begin())
301 FunctionInnards << ", ";
302 printType(FunctionInnards, *I, "");
304 if (MTy->isVarArg()) {
305 if (MTy->getNumParams())
306 FunctionInnards << ", ...";
307 } else if (!MTy->getNumParams()) {
308 FunctionInnards << "void";
310 FunctionInnards << ")";
311 std::string tstr = FunctionInnards.str();
312 printType(Out, MTy->getReturnType(), tstr);
315 case Type::StructTyID: {
316 const StructType *STy = cast<StructType>(Ty);
317 Out << NameSoFar + " {\n";
319 for (StructType::element_iterator I = STy->element_begin(),
320 E = STy->element_end(); I != E; ++I) {
322 printType(Out, *I, "field" + utostr(Idx++));
328 case Type::PointerTyID: {
329 const PointerType *PTy = cast<PointerType>(Ty);
330 std::string ptrName = "*" + NameSoFar;
332 if (isa<ArrayType>(PTy->getElementType()))
333 ptrName = "(" + ptrName + ")";
335 return printType(Out, PTy->getElementType(), ptrName);
338 case Type::ArrayTyID: {
339 const ArrayType *ATy = cast<ArrayType>(Ty);
340 unsigned NumElements = ATy->getNumElements();
341 return printType(Out, ATy->getElementType(),
342 NameSoFar + "[" + utostr(NumElements) + "]");
345 case Type::OpaqueTyID: {
346 static int Count = 0;
347 std::string TyName = "struct opaque_" + itostr(Count++);
348 assert(TypeNames.find(Ty) == TypeNames.end());
349 TypeNames[Ty] = TyName;
350 return Out << TyName << " " << NameSoFar;
353 assert(0 && "Unhandled case in getTypeProps!");
360 void CWriter::printConstantArray(ConstantArray *CPA) {
362 // As a special case, print the array as a string if it is an array of
363 // ubytes or an array of sbytes with positive values.
365 const Type *ETy = CPA->getType()->getElementType();
366 bool isString = (ETy == Type::SByteTy || ETy == Type::UByteTy);
368 // Make sure the last character is a null char, as automatically added by C
369 if (isString && (CPA->getNumOperands() == 0 ||
370 !cast<Constant>(*(CPA->op_end()-1))->isNullValue()))
375 // Keep track of whether the last number was a hexadecimal escape
376 bool LastWasHex = false;
378 // Do not include the last character, which we know is null
379 for (unsigned i = 0, e = CPA->getNumOperands()-1; i != e; ++i) {
380 unsigned char C = cast<ConstantInt>(CPA->getOperand(i))->getRawValue();
382 // Print it out literally if it is a printable character. The only thing
383 // to be careful about is when the last letter output was a hex escape
384 // code, in which case we have to be careful not to print out hex digits
385 // explicitly (the C compiler thinks it is a continuation of the previous
386 // character, sheesh...)
388 if (isprint(C) && (!LastWasHex || !isxdigit(C))) {
390 if (C == '"' || C == '\\')
397 case '\n': Out << "\\n"; break;
398 case '\t': Out << "\\t"; break;
399 case '\r': Out << "\\r"; break;
400 case '\v': Out << "\\v"; break;
401 case '\a': Out << "\\a"; break;
402 case '\"': Out << "\\\""; break;
403 case '\'': Out << "\\\'"; break;
406 Out << (char)(( C/16 < 10) ? ( C/16 +'0') : ( C/16 -10+'A'));
407 Out << (char)(((C&15) < 10) ? ((C&15)+'0') : ((C&15)-10+'A'));
416 if (CPA->getNumOperands()) {
418 printConstant(cast<Constant>(CPA->getOperand(0)));
419 for (unsigned i = 1, e = CPA->getNumOperands(); i != e; ++i) {
421 printConstant(cast<Constant>(CPA->getOperand(i)));
428 // isFPCSafeToPrint - Returns true if we may assume that CFP may be written out
429 // textually as a double (rather than as a reference to a stack-allocated
430 // variable). We decide this by converting CFP to a string and back into a
431 // double, and then checking whether the conversion results in a bit-equal
432 // double to the original value of CFP. This depends on us and the target C
433 // compiler agreeing on the conversion process (which is pretty likely since we
434 // only deal in IEEE FP).
436 static bool isFPCSafeToPrint(const ConstantFP *CFP) {
439 sprintf(Buffer, "%a", CFP->getValue());
441 if (!strncmp(Buffer, "0x", 2) ||
442 !strncmp(Buffer, "-0x", 3) ||
443 !strncmp(Buffer, "+0x", 3))
444 return atof(Buffer) == CFP->getValue();
447 std::string StrVal = ftostr(CFP->getValue());
449 while (StrVal[0] == ' ')
450 StrVal.erase(StrVal.begin());
452 // Check to make sure that the stringized number is not some string like "Inf"
453 // or NaN. Check that the string matches the "[-+]?[0-9]" regex.
454 if ((StrVal[0] >= '0' && StrVal[0] <= '9') ||
455 ((StrVal[0] == '-' || StrVal[0] == '+') &&
456 (StrVal[1] >= '0' && StrVal[1] <= '9')))
457 // Reparse stringized version!
458 return atof(StrVal.c_str()) == CFP->getValue();
463 // printConstant - The LLVM Constant to C Constant converter.
464 void CWriter::printConstant(Constant *CPV) {
465 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CPV)) {
466 switch (CE->getOpcode()) {
467 case Instruction::Cast:
469 printType(Out, CPV->getType());
471 printConstant(CE->getOperand(0));
475 case Instruction::GetElementPtr:
477 printIndexingExpression(CE->getOperand(0), gep_type_begin(CPV),
481 case Instruction::Select:
483 printConstant(CE->getOperand(0));
485 printConstant(CE->getOperand(1));
487 printConstant(CE->getOperand(2));
490 case Instruction::Add:
491 case Instruction::Sub:
492 case Instruction::Mul:
493 case Instruction::Div:
494 case Instruction::Rem:
495 case Instruction::SetEQ:
496 case Instruction::SetNE:
497 case Instruction::SetLT:
498 case Instruction::SetLE:
499 case Instruction::SetGT:
500 case Instruction::SetGE:
501 case Instruction::Shl:
502 case Instruction::Shr:
504 printConstant(CE->getOperand(0));
505 switch (CE->getOpcode()) {
506 case Instruction::Add: Out << " + "; break;
507 case Instruction::Sub: Out << " - "; break;
508 case Instruction::Mul: Out << " * "; break;
509 case Instruction::Div: Out << " / "; break;
510 case Instruction::Rem: Out << " % "; break;
511 case Instruction::SetEQ: Out << " == "; break;
512 case Instruction::SetNE: Out << " != "; break;
513 case Instruction::SetLT: Out << " < "; break;
514 case Instruction::SetLE: Out << " <= "; break;
515 case Instruction::SetGT: Out << " > "; break;
516 case Instruction::SetGE: Out << " >= "; break;
517 case Instruction::Shl: Out << " << "; break;
518 case Instruction::Shr: Out << " >> "; break;
519 default: assert(0 && "Illegal opcode here!");
521 printConstant(CE->getOperand(1));
526 std::cerr << "CWriter Error: Unhandled constant expression: "
530 } else if (isa<UndefValue>(CPV) && CPV->getType()->isFirstClassType()) {
532 printType(Out, CPV->getType());
533 Out << ")/*UNDEF*/0)";
537 switch (CPV->getType()->getTypeID()) {
539 Out << (CPV == ConstantBool::False ? "0" : "1"); break;
540 case Type::SByteTyID:
541 case Type::ShortTyID:
542 Out << cast<ConstantSInt>(CPV)->getValue(); break;
544 if ((int)cast<ConstantSInt>(CPV)->getValue() == (int)0x80000000)
545 Out << "((int)0x80000000U)"; // Handle MININT specially to avoid warning
547 Out << cast<ConstantSInt>(CPV)->getValue();
551 if (cast<ConstantSInt>(CPV)->isMinValue())
552 Out << "(/*INT64_MIN*/(-9223372036854775807LL)-1)";
554 Out << cast<ConstantSInt>(CPV)->getValue() << "ll"; break;
556 case Type::UByteTyID:
557 case Type::UShortTyID:
558 Out << cast<ConstantUInt>(CPV)->getValue(); break;
560 Out << cast<ConstantUInt>(CPV)->getValue() << "u"; break;
561 case Type::ULongTyID:
562 Out << cast<ConstantUInt>(CPV)->getValue() << "ull"; break;
564 case Type::FloatTyID:
565 case Type::DoubleTyID: {
566 ConstantFP *FPC = cast<ConstantFP>(CPV);
567 std::map<const ConstantFP*, unsigned>::iterator I = FPConstantMap.find(FPC);
568 if (I != FPConstantMap.end()) {
569 // Because of FP precision problems we must load from a stack allocated
570 // value that holds the value in hex.
571 Out << "(*(" << (FPC->getType() == Type::FloatTy ? "float" : "double")
572 << "*)&FPConstant" << I->second << ")";
574 if (IsNAN(FPC->getValue())) {
577 // The prefix for a quiet NaN is 0x7FF8. For a signalling NaN,
579 const unsigned long QuietNaN = 0x7ff8UL;
580 const unsigned long SignalNaN = 0x7ff4UL;
582 // We need to grab the first part of the FP #
589 DHex.d = FPC->getValue();
590 sprintf(Buffer, "0x%llx", (unsigned long long)DHex.ll);
592 std::string Num(&Buffer[0], &Buffer[6]);
593 unsigned long Val = strtoul(Num.c_str(), 0, 16);
595 if (FPC->getType() == Type::FloatTy)
596 Out << "LLVM_NAN" << (Val == QuietNaN ? "" : "S") << "F(\""
597 << Buffer << "\") /*nan*/ ";
599 Out << "LLVM_NAN" << (Val == QuietNaN ? "" : "S") << "(\""
600 << Buffer << "\") /*nan*/ ";
601 } else if (IsInf(FPC->getValue())) {
603 if (FPC->getValue() < 0) Out << "-";
604 Out << "LLVM_INF" << (FPC->getType() == Type::FloatTy ? "F" : "")
609 // Print out the constant as a floating point number.
611 sprintf(Buffer, "%a", FPC->getValue());
614 Num = ftostr(FPC->getValue());
622 case Type::ArrayTyID:
623 if (isa<ConstantAggregateZero>(CPV) || isa<UndefValue>(CPV)) {
624 const ArrayType *AT = cast<ArrayType>(CPV->getType());
626 if (AT->getNumElements()) {
628 Constant *CZ = Constant::getNullValue(AT->getElementType());
630 for (unsigned i = 1, e = AT->getNumElements(); i != e; ++i) {
637 printConstantArray(cast<ConstantArray>(CPV));
641 case Type::StructTyID:
642 if (isa<ConstantAggregateZero>(CPV) || isa<UndefValue>(CPV)) {
643 const StructType *ST = cast<StructType>(CPV->getType());
645 if (ST->getNumElements()) {
647 printConstant(Constant::getNullValue(ST->getElementType(0)));
648 for (unsigned i = 1, e = ST->getNumElements(); i != e; ++i) {
650 printConstant(Constant::getNullValue(ST->getElementType(i)));
656 if (CPV->getNumOperands()) {
658 printConstant(cast<Constant>(CPV->getOperand(0)));
659 for (unsigned i = 1, e = CPV->getNumOperands(); i != e; ++i) {
661 printConstant(cast<Constant>(CPV->getOperand(i)));
668 case Type::PointerTyID:
669 if (isa<ConstantPointerNull>(CPV)) {
671 printType(Out, CPV->getType());
672 Out << ")/*NULL*/0)";
674 } else if (GlobalValue *GV = dyn_cast<GlobalValue>(CPV)) {
680 std::cerr << "Unknown constant type: " << *CPV << "\n";
685 void CWriter::writeOperandInternal(Value *Operand) {
686 if (Instruction *I = dyn_cast<Instruction>(Operand))
687 if (isInlinableInst(*I) && !isDirectAlloca(I)) {
688 // Should we inline this instruction to build a tree?
695 Constant* CPV = dyn_cast<Constant>(Operand);
696 if (CPV && !isa<GlobalValue>(CPV)) {
699 Out << Mang->getValueName(Operand);
703 void CWriter::writeOperand(Value *Operand) {
704 if (isa<GlobalVariable>(Operand) || isDirectAlloca(Operand))
705 Out << "(&"; // Global variables are references as their addresses by llvm
707 writeOperandInternal(Operand);
709 if (isa<GlobalVariable>(Operand) || isDirectAlloca(Operand))
713 // generateCompilerSpecificCode - This is where we add conditional compilation
714 // directives to cater to specific compilers as need be.
716 static void generateCompilerSpecificCode(std::ostream& Out) {
717 // Alloca is hard to get, and we don't want to include stdlib.h here...
718 Out << "/* get a declaration for alloca */\n"
719 << "#if defined(__CYGWIN__) || defined(__APPLE__)\n"
720 << "extern void *__builtin_alloca(unsigned long);\n"
721 << "#define alloca(x) __builtin_alloca(x)\n"
722 << "#elif defined(__sun__)\n"
723 << "#if defined(__sparcv9)\n"
724 << "extern void *__builtin_alloca(unsigned long);\n"
726 << "extern void *__builtin_alloca(unsigned int);\n"
728 << "#define alloca(x) __builtin_alloca(x)\n"
729 << "#elif defined(__FreeBSD__)\n"
730 << "#define alloca(x) __builtin_alloca(x)\n"
732 << "#include <alloca.h>\n"
735 // We output GCC specific attributes to preserve 'linkonce'ness on globals.
736 // If we aren't being compiled with GCC, just drop these attributes.
737 Out << "#ifndef __GNUC__ /* Can only support \"linkonce\" vars with GCC */\n"
738 << "#define __attribute__(X)\n"
742 // At some point, we should support "external weak" vs. "weak" linkages.
743 // On Mac OS X, "external weak" is spelled "__attribute__((weak_import))".
744 Out << "#if defined(__GNUC__) && defined(__APPLE_CC__)\n"
745 << "#define __EXTERNAL_WEAK__ __attribute__((weak_import))\n"
746 << "#elif defined(__GNUC__)\n"
747 << "#define __EXTERNAL_WEAK__ __attribute__((weak))\n"
749 << "#define __EXTERNAL_WEAK__\n"
753 // For now, turn off the weak linkage attribute on Mac OS X. (See above.)
754 Out << "#if defined(__GNUC__) && defined(__APPLE_CC__)\n"
755 << "#define __ATTRIBUTE_WEAK__\n"
756 << "#elif defined(__GNUC__)\n"
757 << "#define __ATTRIBUTE_WEAK__ __attribute__((weak))\n"
759 << "#define __ATTRIBUTE_WEAK__\n"
762 // Define NaN and Inf as GCC builtins if using GCC, as 0 otherwise
763 // From the GCC documentation:
765 // double __builtin_nan (const char *str)
767 // This is an implementation of the ISO C99 function nan.
769 // Since ISO C99 defines this function in terms of strtod, which we do
770 // not implement, a description of the parsing is in order. The string is
771 // parsed as by strtol; that is, the base is recognized by leading 0 or
772 // 0x prefixes. The number parsed is placed in the significand such that
773 // the least significant bit of the number is at the least significant
774 // bit of the significand. The number is truncated to fit the significand
775 // field provided. The significand is forced to be a quiet NaN.
777 // This function, if given a string literal, is evaluated early enough
778 // that it is considered a compile-time constant.
780 // float __builtin_nanf (const char *str)
782 // Similar to __builtin_nan, except the return type is float.
784 // double __builtin_inf (void)
786 // Similar to __builtin_huge_val, except a warning is generated if the
787 // target floating-point format does not support infinities. This
788 // function is suitable for implementing the ISO C99 macro INFINITY.
790 // float __builtin_inff (void)
792 // Similar to __builtin_inf, except the return type is float.
793 Out << "#ifdef __GNUC__\n"
794 << "#define LLVM_NAN(NanStr) __builtin_nan(NanStr) /* Double */\n"
795 << "#define LLVM_NANF(NanStr) __builtin_nanf(NanStr) /* Float */\n"
796 << "#define LLVM_NANS(NanStr) __builtin_nans(NanStr) /* Double */\n"
797 << "#define LLVM_NANSF(NanStr) __builtin_nansf(NanStr) /* Float */\n"
798 << "#define LLVM_INF __builtin_inf() /* Double */\n"
799 << "#define LLVM_INFF __builtin_inff() /* Float */\n"
801 << "#define LLVM_NAN(NanStr) ((double)0.0) /* Double */\n"
802 << "#define LLVM_NANF(NanStr) 0.0F /* Float */\n"
803 << "#define LLVM_NANS(NanStr) ((double)0.0) /* Double */\n"
804 << "#define LLVM_NANSF(NanStr) 0.0F /* Float */\n"
805 << "#define LLVM_INF ((double)0.0) /* Double */\n"
806 << "#define LLVM_INFF 0.0F /* Float */\n"
810 bool CWriter::doInitialization(Module &M) {
816 // Ensure that all structure types have names...
817 Mang = new Mangler(M);
819 // get declaration for alloca
820 Out << "/* Provide Declarations */\n";
821 Out << "#include <stdarg.h>\n"; // Varargs support
822 Out << "#include <setjmp.h>\n"; // Unwind support
823 generateCompilerSpecificCode(Out);
825 // Provide a definition for `bool' if not compiling with a C++ compiler.
827 << "#ifndef __cplusplus\ntypedef unsigned char bool;\n#endif\n"
829 << "\n\n/* Support for floating point constants */\n"
830 << "typedef unsigned long long ConstantDoubleTy;\n"
831 << "typedef unsigned int ConstantFloatTy;\n"
833 << "\n\n/* Global Declarations */\n";
835 // First output all the declarations for the program, because C requires
836 // Functions & globals to be declared before they are used.
839 // Loop over the symbol table, emitting all named constants...
840 printModuleTypes(M.getSymbolTable());
842 // Global variable declarations...
844 Out << "\n/* External Global Variable Declarations */\n";
845 for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++I) {
846 if (I->hasExternalLinkage()) {
848 printType(Out, I->getType()->getElementType(), Mang->getValueName(I));
854 // Function declarations
856 Out << "\n/* Function Declarations */\n";
857 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
858 // Don't print declarations for intrinsic functions.
859 if (!I->getIntrinsicID() &&
860 I->getName() != "setjmp" && I->getName() != "longjmp") {
861 printFunctionSignature(I, true);
862 if (I->hasWeakLinkage()) Out << " __ATTRIBUTE_WEAK__";
863 if (I->hasLinkOnceLinkage()) Out << " __ATTRIBUTE_WEAK__";
869 // Output the global variable declarations
871 Out << "\n\n/* Global Variable Declarations */\n";
872 for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
873 if (!I->isExternal()) {
874 if (I->hasInternalLinkage())
878 printType(Out, I->getType()->getElementType(), Mang->getValueName(I));
880 if (I->hasLinkOnceLinkage())
881 Out << " __attribute__((common))";
882 else if (I->hasWeakLinkage())
883 Out << " __ATTRIBUTE_WEAK__";
888 // Output the global variable definitions and contents...
890 Out << "\n\n/* Global Variable Definitions and Initialization */\n";
891 for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
892 if (!I->isExternal()) {
893 if (I->hasInternalLinkage())
895 printType(Out, I->getType()->getElementType(), Mang->getValueName(I));
896 if (I->hasLinkOnceLinkage())
897 Out << " __attribute__((common))";
898 else if (I->hasWeakLinkage())
899 Out << " __ATTRIBUTE_WEAK__";
901 // If the initializer is not null, emit the initializer. If it is null,
902 // we try to avoid emitting large amounts of zeros. The problem with
903 // this, however, occurs when the variable has weak linkage. In this
904 // case, the assembler will complain about the variable being both weak
905 // and common, so we disable this optimization.
906 if (!I->getInitializer()->isNullValue()) {
908 writeOperand(I->getInitializer());
909 } else if (I->hasWeakLinkage()) {
910 // We have to specify an initializer, but it doesn't have to be
911 // complete. If the value is an aggregate, print out { 0 }, and let
912 // the compiler figure out the rest of the zeros.
914 if (isa<StructType>(I->getInitializer()->getType()) ||
915 isa<ArrayType>(I->getInitializer()->getType())) {
918 // Just print it out normally.
919 writeOperand(I->getInitializer());
927 Out << "\n\n/* Function Bodies */\n";
932 /// Output all floating point constants that cannot be printed accurately...
933 void CWriter::printFloatingPointConstants(Function &F) {
944 // Scan the module for floating point constants. If any FP constant is used
945 // in the function, we want to redirect it here so that we do not depend on
946 // the precision of the printed form, unless the printed form preserves
949 static unsigned FPCounter = 0;
950 for (constant_iterator I = constant_begin(&F), E = constant_end(&F);
952 if (const ConstantFP *FPC = dyn_cast<ConstantFP>(*I))
953 if (!isFPCSafeToPrint(FPC) && // Do not put in FPConstantMap if safe.
954 !FPConstantMap.count(FPC)) {
955 double Val = FPC->getValue();
957 FPConstantMap[FPC] = FPCounter; // Number the FP constants
959 if (FPC->getType() == Type::DoubleTy) {
961 Out << "static const ConstantDoubleTy FPConstant" << FPCounter++
962 << " = 0x" << std::hex << DBLUnion.U << std::dec
963 << "ULL; /* " << Val << " */\n";
964 } else if (FPC->getType() == Type::FloatTy) {
966 Out << "static const ConstantFloatTy FPConstant" << FPCounter++
967 << " = 0x" << std::hex << FLTUnion.U << std::dec
968 << "U; /* " << Val << " */\n";
970 assert(0 && "Unknown float type!");
977 /// printSymbolTable - Run through symbol table looking for type names. If a
978 /// type name is found, emit it's declaration...
980 void CWriter::printModuleTypes(const SymbolTable &ST) {
981 // If there are no type names, exit early.
982 if ( ! ST.hasTypes() )
985 // We are only interested in the type plane of the symbol table...
986 SymbolTable::type_const_iterator I = ST.type_begin();
987 SymbolTable::type_const_iterator End = ST.type_end();
989 // Print out forward declarations for structure types before anything else!
990 Out << "/* Structure forward decls */\n";
991 for (; I != End; ++I)
992 if (const Type *STy = dyn_cast<StructType>(I->second)) {
993 std::string Name = "struct l_" + Mangler::makeNameProper(I->first);
994 Out << Name << ";\n";
995 TypeNames.insert(std::make_pair(STy, Name));
1000 // Now we can print out typedefs...
1001 Out << "/* Typedefs */\n";
1002 for (I = ST.type_begin(); I != End; ++I) {
1003 const Type *Ty = cast<Type>(I->second);
1004 std::string Name = "l_" + Mangler::makeNameProper(I->first);
1006 printType(Out, Ty, Name);
1012 // Keep track of which structures have been printed so far...
1013 std::set<const StructType *> StructPrinted;
1015 // Loop over all structures then push them into the stack so they are
1016 // printed in the correct order.
1018 Out << "/* Structure contents */\n";
1019 for (I = ST.type_begin(); I != End; ++I)
1020 if (const StructType *STy = dyn_cast<StructType>(I->second))
1021 // Only print out used types!
1022 printContainedStructs(STy, StructPrinted);
1025 // Push the struct onto the stack and recursively push all structs
1026 // this one depends on.
1027 void CWriter::printContainedStructs(const Type *Ty,
1028 std::set<const StructType*> &StructPrinted){
1029 if (const StructType *STy = dyn_cast<StructType>(Ty)) {
1030 //Check to see if we have already printed this struct
1031 if (StructPrinted.count(STy) == 0) {
1032 // Print all contained types first...
1033 for (StructType::element_iterator I = STy->element_begin(),
1034 E = STy->element_end(); I != E; ++I) {
1035 const Type *Ty1 = I->get();
1036 if (isa<StructType>(Ty1) || isa<ArrayType>(Ty1))
1037 printContainedStructs(*I, StructPrinted);
1040 //Print structure type out..
1041 StructPrinted.insert(STy);
1042 std::string Name = TypeNames[STy];
1043 printType(Out, STy, Name, true);
1047 // If it is an array, check contained types and continue
1048 } else if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)){
1049 const Type *Ty1 = ATy->getElementType();
1050 if (isa<StructType>(Ty1) || isa<ArrayType>(Ty1))
1051 printContainedStructs(Ty1, StructPrinted);
1056 void CWriter::printFunctionSignature(const Function *F, bool Prototype) {
1057 if (F->hasInternalLinkage()) Out << "static ";
1059 // Loop over the arguments, printing them...
1060 const FunctionType *FT = cast<FunctionType>(F->getFunctionType());
1062 std::stringstream FunctionInnards;
1064 // Print out the name...
1065 FunctionInnards << Mang->getValueName(F) << "(";
1067 if (!F->isExternal()) {
1069 std::string ArgName;
1070 if (F->abegin()->hasName() || !Prototype)
1071 ArgName = Mang->getValueName(F->abegin());
1072 printType(FunctionInnards, F->afront().getType(), ArgName);
1073 for (Function::const_aiterator I = ++F->abegin(), E = F->aend();
1075 FunctionInnards << ", ";
1076 if (I->hasName() || !Prototype)
1077 ArgName = Mang->getValueName(I);
1080 printType(FunctionInnards, I->getType(), ArgName);
1084 // Loop over the arguments, printing them...
1085 for (FunctionType::param_iterator I = FT->param_begin(),
1086 E = FT->param_end(); I != E; ++I) {
1087 if (I != FT->param_begin()) FunctionInnards << ", ";
1088 printType(FunctionInnards, *I);
1092 // Finish printing arguments... if this is a vararg function, print the ...,
1093 // unless there are no known types, in which case, we just emit ().
1095 if (FT->isVarArg() && FT->getNumParams()) {
1096 if (FT->getNumParams()) FunctionInnards << ", ";
1097 FunctionInnards << "..."; // Output varargs portion of signature!
1098 } else if (!FT->isVarArg() && FT->getNumParams() == 0) {
1099 FunctionInnards << "void"; // ret() -> ret(void) in C.
1101 FunctionInnards << ")";
1102 // Print out the return type and the entire signature for that matter
1103 printType(Out, F->getReturnType(), FunctionInnards.str());
1106 void CWriter::printFunction(Function &F) {
1107 printFunctionSignature(&F, false);
1110 // print local variable information for the function
1111 for (inst_iterator I = inst_begin(&F), E = inst_end(&F); I != E; ++I)
1112 if (const AllocaInst *AI = isDirectAlloca(&*I)) {
1114 printType(Out, AI->getAllocatedType(), Mang->getValueName(AI));
1115 Out << "; /* Address exposed local */\n";
1116 } else if (I->getType() != Type::VoidTy && !isInlinableInst(*I)) {
1118 printType(Out, I->getType(), Mang->getValueName(&*I));
1121 if (isa<PHINode>(*I)) { // Print out PHI node temporaries as well...
1123 printType(Out, I->getType(),
1124 Mang->getValueName(&*I)+"__PHI_TEMPORARY");
1131 if (F.hasExternalLinkage() && F.getName() == "main")
1134 // print the basic blocks
1135 for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
1136 if (Loop *L = LI->getLoopFor(BB)) {
1137 if (L->getHeader() == BB && L->getParentLoop() == 0)
1140 printBasicBlock(BB);
1147 void CWriter::printCodeForMain() {
1148 // On X86, set the FP control word to 64-bits of precision instead of 80 bits.
1149 Out << "#if defined(__GNUC__) && !defined(__llvm__)\n"
1150 << "#if defined(i386) || defined(__i386__) || defined(__i386)\n"
1151 << "{short FPCW;__asm__ (\"fnstcw %0\" : \"=m\" (*&FPCW));\n"
1152 << "FPCW=(FPCW&~0x300)|0x200;__asm__(\"fldcw %0\" :: \"m\" (*&FPCW));}\n"
1153 << "#endif\n#endif\n";
1156 void CWriter::printLoop(Loop *L) {
1157 Out << " do { /* Syntactic loop '" << L->getHeader()->getName()
1158 << "' to make GCC happy */\n";
1159 for (unsigned i = 0, e = L->getBlocks().size(); i != e; ++i) {
1160 BasicBlock *BB = L->getBlocks()[i];
1161 Loop *BBLoop = LI->getLoopFor(BB);
1163 printBasicBlock(BB);
1164 else if (BB == BBLoop->getHeader() && BBLoop->getParentLoop() == L)
1167 Out << " } while (1); /* end of syntactic loop '"
1168 << L->getHeader()->getName() << "' */\n";
1171 void CWriter::printBasicBlock(BasicBlock *BB) {
1173 // Don't print the label for the basic block if there are no uses, or if
1174 // the only terminator use is the predecessor basic block's terminator.
1175 // We have to scan the use list because PHI nodes use basic blocks too but
1176 // do not require a label to be generated.
1178 bool NeedsLabel = false;
1179 for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
1180 if (isGotoCodeNecessary(*PI, BB)) {
1185 if (NeedsLabel) Out << Mang->getValueName(BB) << ":\n";
1187 // Output all of the instructions in the basic block...
1188 for (BasicBlock::iterator II = BB->begin(), E = --BB->end(); II != E;
1190 if (!isInlinableInst(*II) && !isDirectAlloca(II)) {
1191 if (II->getType() != Type::VoidTy)
1200 // Don't emit prefix or suffix for the terminator...
1201 visit(*BB->getTerminator());
1205 // Specific Instruction type classes... note that all of the casts are
1206 // necessary because we use the instruction classes as opaque types...
1208 void CWriter::visitReturnInst(ReturnInst &I) {
1209 // Don't output a void return if this is the last basic block in the function
1210 if (I.getNumOperands() == 0 &&
1211 &*--I.getParent()->getParent()->end() == I.getParent() &&
1212 !I.getParent()->size() == 1) {
1217 if (I.getNumOperands()) {
1219 writeOperand(I.getOperand(0));
1224 void CWriter::visitSwitchInst(SwitchInst &SI) {
1227 writeOperand(SI.getOperand(0));
1228 Out << ") {\n default:\n";
1229 printPHICopiesForSuccessor (SI.getParent(), SI.getDefaultDest(), 2);
1230 printBranchToBlock(SI.getParent(), SI.getDefaultDest(), 2);
1232 for (unsigned i = 2, e = SI.getNumOperands(); i != e; i += 2) {
1234 writeOperand(SI.getOperand(i));
1236 BasicBlock *Succ = cast<BasicBlock>(SI.getOperand(i+1));
1237 printPHICopiesForSuccessor (SI.getParent(), Succ, 2);
1238 printBranchToBlock(SI.getParent(), Succ, 2);
1239 if (Succ == SI.getParent()->getNext())
1245 void CWriter::visitUnreachableInst(UnreachableInst &I) {
1246 Out << " /*UNREACHABLE*/;\n";
1249 bool CWriter::isGotoCodeNecessary(BasicBlock *From, BasicBlock *To) {
1250 /// FIXME: This should be reenabled, but loop reordering safe!!
1253 if (From->getNext() != To) // Not the direct successor, we need a goto
1256 //isa<SwitchInst>(From->getTerminator())
1259 if (LI->getLoopFor(From) != LI->getLoopFor(To))
1264 void CWriter::printPHICopiesForSuccessor (BasicBlock *CurBlock,
1265 BasicBlock *Successor,
1267 for (BasicBlock::iterator I = Successor->begin(); isa<PHINode>(I); ++I) {
1268 PHINode *PN = cast<PHINode>(I);
1269 // Now we have to do the printing.
1270 Value *IV = PN->getIncomingValueForBlock(CurBlock);
1271 if (!isa<UndefValue>(IV)) {
1272 Out << std::string(Indent, ' ');
1273 Out << " " << Mang->getValueName(I) << "__PHI_TEMPORARY = ";
1275 Out << "; /* for PHI node */\n";
1280 void CWriter::printBranchToBlock(BasicBlock *CurBB, BasicBlock *Succ,
1282 if (isGotoCodeNecessary(CurBB, Succ)) {
1283 Out << std::string(Indent, ' ') << " goto ";
1289 // Branch instruction printing - Avoid printing out a branch to a basic block
1290 // that immediately succeeds the current one.
1292 void CWriter::visitBranchInst(BranchInst &I) {
1294 if (I.isConditional()) {
1295 if (isGotoCodeNecessary(I.getParent(), I.getSuccessor(0))) {
1297 writeOperand(I.getCondition());
1300 printPHICopiesForSuccessor (I.getParent(), I.getSuccessor(0), 2);
1301 printBranchToBlock(I.getParent(), I.getSuccessor(0), 2);
1303 if (isGotoCodeNecessary(I.getParent(), I.getSuccessor(1))) {
1304 Out << " } else {\n";
1305 printPHICopiesForSuccessor (I.getParent(), I.getSuccessor(1), 2);
1306 printBranchToBlock(I.getParent(), I.getSuccessor(1), 2);
1309 // First goto not necessary, assume second one is...
1311 writeOperand(I.getCondition());
1314 printPHICopiesForSuccessor (I.getParent(), I.getSuccessor(1), 2);
1315 printBranchToBlock(I.getParent(), I.getSuccessor(1), 2);
1320 printPHICopiesForSuccessor (I.getParent(), I.getSuccessor(0), 0);
1321 printBranchToBlock(I.getParent(), I.getSuccessor(0), 0);
1326 // PHI nodes get copied into temporary values at the end of predecessor basic
1327 // blocks. We now need to copy these temporary values into the REAL value for
1329 void CWriter::visitPHINode(PHINode &I) {
1331 Out << "__PHI_TEMPORARY";
1335 void CWriter::visitBinaryOperator(Instruction &I) {
1336 // binary instructions, shift instructions, setCond instructions.
1337 assert(!isa<PointerType>(I.getType()));
1339 // We must cast the results of binary operations which might be promoted.
1340 bool needsCast = false;
1341 if ((I.getType() == Type::UByteTy) || (I.getType() == Type::SByteTy)
1342 || (I.getType() == Type::UShortTy) || (I.getType() == Type::ShortTy)
1343 || (I.getType() == Type::FloatTy)) {
1346 printType(Out, I.getType());
1350 writeOperand(I.getOperand(0));
1352 switch (I.getOpcode()) {
1353 case Instruction::Add: Out << " + "; break;
1354 case Instruction::Sub: Out << " - "; break;
1355 case Instruction::Mul: Out << "*"; break;
1356 case Instruction::Div: Out << "/"; break;
1357 case Instruction::Rem: Out << "%"; break;
1358 case Instruction::And: Out << " & "; break;
1359 case Instruction::Or: Out << " | "; break;
1360 case Instruction::Xor: Out << " ^ "; break;
1361 case Instruction::SetEQ: Out << " == "; break;
1362 case Instruction::SetNE: Out << " != "; break;
1363 case Instruction::SetLE: Out << " <= "; break;
1364 case Instruction::SetGE: Out << " >= "; break;
1365 case Instruction::SetLT: Out << " < "; break;
1366 case Instruction::SetGT: Out << " > "; break;
1367 case Instruction::Shl : Out << " << "; break;
1368 case Instruction::Shr : Out << " >> "; break;
1369 default: std::cerr << "Invalid operator type!" << I; abort();
1372 writeOperand(I.getOperand(1));
1379 void CWriter::visitCastInst(CastInst &I) {
1380 if (I.getType() == Type::BoolTy) {
1382 writeOperand(I.getOperand(0));
1387 printType(Out, I.getType());
1389 if (isa<PointerType>(I.getType())&&I.getOperand(0)->getType()->isIntegral() ||
1390 isa<PointerType>(I.getOperand(0)->getType())&&I.getType()->isIntegral()) {
1391 // Avoid "cast to pointer from integer of different size" warnings
1395 writeOperand(I.getOperand(0));
1398 void CWriter::visitSelectInst(SelectInst &I) {
1400 writeOperand(I.getCondition());
1402 writeOperand(I.getTrueValue());
1404 writeOperand(I.getFalseValue());
1409 void CWriter::lowerIntrinsics(Function &F) {
1410 for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
1411 for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; )
1412 if (CallInst *CI = dyn_cast<CallInst>(I++))
1413 if (Function *F = CI->getCalledFunction())
1414 switch (F->getIntrinsicID()) {
1415 case Intrinsic::not_intrinsic:
1416 case Intrinsic::vastart:
1417 case Intrinsic::vacopy:
1418 case Intrinsic::vaend:
1419 case Intrinsic::returnaddress:
1420 case Intrinsic::frameaddress:
1421 case Intrinsic::setjmp:
1422 case Intrinsic::longjmp:
1423 // We directly implement these intrinsics
1426 // All other intrinsic calls we must lower.
1427 Instruction *Before = CI->getPrev();
1428 IL.LowerIntrinsicCall(CI);
1429 if (Before) { // Move iterator to instruction after call
1439 void CWriter::visitCallInst(CallInst &I) {
1440 // Handle intrinsic function calls first...
1441 if (Function *F = I.getCalledFunction())
1442 if (Intrinsic::ID ID = (Intrinsic::ID)F->getIntrinsicID()) {
1444 default: assert(0 && "Unknown LLVM intrinsic!");
1445 case Intrinsic::vastart:
1448 Out << "va_start(*(va_list*)&" << Mang->getValueName(&I) << ", ";
1449 // Output the last argument to the enclosing function...
1450 if (I.getParent()->getParent()->aempty()) {
1451 std::cerr << "The C backend does not currently support zero "
1452 << "argument varargs functions, such as '"
1453 << I.getParent()->getParent()->getName() << "'!\n";
1456 writeOperand(&I.getParent()->getParent()->aback());
1459 case Intrinsic::vaend:
1460 if (!isa<ConstantPointerNull>(I.getOperand(1))) {
1461 Out << "va_end(*(va_list*)&";
1462 writeOperand(I.getOperand(1));
1465 Out << "va_end(*(va_list*)0)";
1468 case Intrinsic::vacopy:
1470 Out << "va_copy(*(va_list*)&" << Mang->getValueName(&I) << ", ";
1471 Out << "*(va_list*)&";
1472 writeOperand(I.getOperand(1));
1475 case Intrinsic::returnaddress:
1476 Out << "__builtin_return_address(";
1477 writeOperand(I.getOperand(1));
1480 case Intrinsic::frameaddress:
1481 Out << "__builtin_frame_address(";
1482 writeOperand(I.getOperand(1));
1485 case Intrinsic::setjmp:
1486 Out << "setjmp(*(jmp_buf*)";
1487 writeOperand(I.getOperand(1));
1490 case Intrinsic::longjmp:
1491 Out << "longjmp(*(jmp_buf*)";
1492 writeOperand(I.getOperand(1));
1494 writeOperand(I.getOperand(2));
1500 Value *Callee = I.getCalledValue();
1502 // GCC is really a PITA. It does not permit codegening casts of functions to
1503 // function pointers if they are in a call (it generates a trap instruction
1504 // instead!). We work around this by inserting a cast to void* in between the
1505 // function and the function pointer cast. Unfortunately, we can't just form
1506 // the constant expression here, because the folder will immediately nuke it.
1508 // Note finally, that this is completely unsafe. ANSI C does not guarantee
1509 // that void* and function pointers have the same size. :( To deal with this
1510 // in the common case, we handle casts where the number of arguments passed
1513 bool WroteCallee = false;
1514 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Callee))
1515 if (CE->getOpcode() == Instruction::Cast)
1516 if (Function *RF = dyn_cast<Function>(CE->getOperand(0))) {
1517 const FunctionType *RFTy = RF->getFunctionType();
1518 if (RFTy->getNumParams() == I.getNumOperands()-1) {
1519 // If the call site expects a value, and the actual callee doesn't
1520 // provide one, return 0.
1521 if (I.getType() != Type::VoidTy &&
1522 RFTy->getReturnType() == Type::VoidTy)
1523 Out << "0 /*actual callee doesn't return value*/; ";
1526 // Ok, just cast the pointer type.
1528 printType(Out, CE->getType());
1536 const PointerType *PTy = cast<PointerType>(Callee->getType());
1537 const FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1538 const Type *RetTy = FTy->getReturnType();
1540 if (!WroteCallee) writeOperand(Callee);
1543 unsigned NumDeclaredParams = FTy->getNumParams();
1545 if (I.getNumOperands() != 1) {
1546 CallSite::arg_iterator AI = I.op_begin()+1, AE = I.op_end();
1547 if (NumDeclaredParams && (*AI)->getType() != FTy->getParamType(0)) {
1549 printType(Out, FTy->getParamType(0));
1556 for (ArgNo = 1, ++AI; AI != AE; ++AI, ++ArgNo) {
1558 if (ArgNo < NumDeclaredParams &&
1559 (*AI)->getType() != FTy->getParamType(ArgNo)) {
1561 printType(Out, FTy->getParamType(ArgNo));
1570 void CWriter::visitMallocInst(MallocInst &I) {
1571 assert(0 && "lowerallocations pass didn't work!");
1574 void CWriter::visitAllocaInst(AllocaInst &I) {
1576 printType(Out, I.getType());
1577 Out << ") alloca(sizeof(";
1578 printType(Out, I.getType()->getElementType());
1580 if (I.isArrayAllocation()) {
1582 writeOperand(I.getOperand(0));
1587 void CWriter::visitFreeInst(FreeInst &I) {
1588 assert(0 && "lowerallocations pass didn't work!");
1591 void CWriter::printIndexingExpression(Value *Ptr, gep_type_iterator I,
1592 gep_type_iterator E) {
1593 bool HasImplicitAddress = false;
1594 // If accessing a global value with no indexing, avoid *(&GV) syndrome
1595 if (GlobalValue *V = dyn_cast<GlobalValue>(Ptr)) {
1596 HasImplicitAddress = true;
1597 } else if (isDirectAlloca(Ptr)) {
1598 HasImplicitAddress = true;
1602 if (!HasImplicitAddress)
1603 Out << "*"; // Implicit zero first argument: '*x' is equivalent to 'x[0]'
1605 writeOperandInternal(Ptr);
1609 const Constant *CI = dyn_cast<Constant>(I.getOperand());
1610 if (HasImplicitAddress && (!CI || !CI->isNullValue()))
1613 writeOperandInternal(Ptr);
1615 if (HasImplicitAddress && (!CI || !CI->isNullValue())) {
1617 HasImplicitAddress = false; // HIA is only true if we haven't addressed yet
1620 assert(!HasImplicitAddress || (CI && CI->isNullValue()) &&
1621 "Can only have implicit address with direct accessing");
1623 if (HasImplicitAddress) {
1625 } else if (CI && CI->isNullValue()) {
1626 gep_type_iterator TmpI = I; ++TmpI;
1628 // Print out the -> operator if possible...
1629 if (TmpI != E && isa<StructType>(*TmpI)) {
1630 Out << (HasImplicitAddress ? "." : "->");
1631 Out << "field" << cast<ConstantUInt>(TmpI.getOperand())->getValue();
1637 if (isa<StructType>(*I)) {
1638 Out << ".field" << cast<ConstantUInt>(I.getOperand())->getValue();
1641 writeOperand(I.getOperand());
1646 void CWriter::visitLoadInst(LoadInst &I) {
1648 writeOperand(I.getOperand(0));
1651 void CWriter::visitStoreInst(StoreInst &I) {
1653 writeOperand(I.getPointerOperand());
1655 writeOperand(I.getOperand(0));
1658 void CWriter::visitGetElementPtrInst(GetElementPtrInst &I) {
1660 printIndexingExpression(I.getPointerOperand(), gep_type_begin(I),
1664 void CWriter::visitVANextInst(VANextInst &I) {
1665 Out << Mang->getValueName(I.getOperand(0));
1666 Out << "; va_arg(*(va_list*)&" << Mang->getValueName(&I) << ", ";
1667 printType(Out, I.getArgType());
1671 void CWriter::visitVAArgInst(VAArgInst &I) {
1673 Out << "{ va_list Tmp; va_copy(Tmp, *(va_list*)&";
1674 writeOperand(I.getOperand(0));
1675 Out << ");\n " << Mang->getValueName(&I) << " = va_arg(Tmp, ";
1676 printType(Out, I.getType());
1677 Out << ");\n va_end(Tmp); }";
1680 //===----------------------------------------------------------------------===//
1681 // External Interface declaration
1682 //===----------------------------------------------------------------------===//
1684 bool CTargetMachine::addPassesToEmitAssembly(PassManager &PM, std::ostream &o) {
1685 PM.add(createLowerGCPass());
1686 PM.add(createLowerAllocationsPass());
1687 PM.add(createLowerInvokePass());
1688 PM.add(new CBackendNameAllUsedStructs());
1689 PM.add(new CWriter(o, getIntrinsicLowering()));