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llvm-6502/lib/Target/CBackend/CBackend.cpp

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//===-- Writer.cpp - Library for converting LLVM code to C ----------------===//
//
// This library converts LLVM code to C code, compilable by GCC.
//
//===-----------------------------------------------------------------------==//
#include "llvm/Assembly/CWriter.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/iMemory.h"
#include "llvm/iTerminators.h"
#include "llvm/iPHINode.h"
#include "llvm/iOther.h"
#include "llvm/iOperators.h"
#include "llvm/Pass.h"
#include "llvm/SymbolTable.h"
#include "llvm/SlotCalculator.h"
#include "llvm/Analysis/FindUsedTypes.h"
#include "llvm/Analysis/ConstantsScanner.h"
#include "llvm/Support/InstVisitor.h"
#include "llvm/Support/InstIterator.h"
#include "Support/StringExtras.h"
#include "Support/STLExtras.h"
#include <algorithm>
#include <set>
using std::string;
using std::map;
using std::ostream;
namespace {
class CWriter : public Pass, public InstVisitor<CWriter> {
ostream &Out;
SlotCalculator *Table;
const Module *TheModule;
map<const Type *, string> TypeNames;
std::set<const Value*> MangledGlobals;
bool needsMalloc;
map<const ConstantFP *, unsigned> FPConstantMap;
public:
CWriter(ostream &o) : Out(o) {}
void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
AU.addRequired<FindUsedTypes>();
}
virtual bool run(Module &M) {
// Initialize
Table = new SlotCalculator(&M, false);
TheModule = &M;
// Ensure that all structure types have names...
bool Changed = nameAllUsedStructureTypes(M);
// Run...
printModule(&M);
// Free memory...
delete Table;
TypeNames.clear();
MangledGlobals.clear();
return false;
}
ostream &printType(const Type *Ty, const string &VariableName = "",
bool IgnoreName = false, bool namedContext = true);
void writeOperand(Value *Operand);
void writeOperandInternal(Value *Operand);
string getValueName(const Value *V);
private :
bool nameAllUsedStructureTypes(Module &M);
void printModule(Module *M);
void printSymbolTable(const SymbolTable &ST);
void printContainedStructs(const Type *Ty, std::set<const StructType *> &);
void printGlobal(const GlobalVariable *GV);
void printFunctionSignature(const Function *F, bool Prototype);
void printFunction(Function *);
void printConstant(Constant *CPV);
void printConstantArray(ConstantArray *CPA);
// isInlinableInst - Attempt to inline instructions into their uses to build
// trees as much as possible. To do this, we have to consistently decide
// what is acceptable to inline, so that variable declarations don't get
// printed and an extra copy of the expr is not emitted.
//
static bool isInlinableInst(const Instruction &I) {
// Must be an expression, must be used exactly once. If it is dead, we
// emit it inline where it would go.
if (I.getType() == Type::VoidTy || I.use_size() != 1 ||
isa<TerminatorInst>(I) || isa<CallInst>(I) || isa<PHINode>(I) ||
isa<LoadInst>(I)) // Don't inline a load across a store!
return false;
// Only inline instruction it it's use is in the same BB as the inst.
return I.getParent() == cast<Instruction>(I.use_back())->getParent();
}
// Instruction visitation functions
friend class InstVisitor<CWriter>;
void visitReturnInst(ReturnInst &I);
void visitBranchInst(BranchInst &I);
void visitPHINode(PHINode &I) {}
void visitBinaryOperator(Instruction &I);
void visitCastInst (CastInst &I);
void visitCallInst (CallInst &I);
void visitShiftInst(ShiftInst &I) { visitBinaryOperator(I); }
void visitMallocInst(MallocInst &I);
void visitAllocaInst(AllocaInst &I);
void visitFreeInst (FreeInst &I);
void visitLoadInst (LoadInst &I);
void visitStoreInst (StoreInst &I);
void visitGetElementPtrInst(GetElementPtrInst &I);
void visitInstruction(Instruction &I) {
std::cerr << "C Writer does not know about " << I;
abort();
}
void outputLValue(Instruction *I) {
Out << " " << getValueName(I) << " = ";
}
void printBranchToBlock(BasicBlock *CurBlock, BasicBlock *SuccBlock,
unsigned Indent);
void printIndexingExpression(Value *Ptr, User::op_iterator I,
User::op_iterator E);
};
}
// We dont want identifier names with ., space, - in them.
// So we replace them with _
static string makeNameProper(string x) {
string tmp;
for (string::iterator sI = x.begin(), sEnd = x.end(); sI != sEnd; sI++)
switch (*sI) {
case '.': tmp += "d_"; break;
case ' ': tmp += "s_"; break;
case '-': tmp += "D_"; break;
default: tmp += *sI;
}
return tmp;
}
string CWriter::getValueName(const Value *V) {
if (V->hasName()) { // Print out the label if it exists...
if (isa<GlobalValue>(V) && // Do not mangle globals...
cast<GlobalValue>(V)->hasExternalLinkage() && // Unless it's internal or
!MangledGlobals.count(V)) // Unless the name would collide if we don't
return makeNameProper(V->getName());
return "l" + utostr(V->getType()->getUniqueID()) + "_" +
makeNameProper(V->getName());
}
int Slot = Table->getValSlot(V);
assert(Slot >= 0 && "Invalid value!");
return "ltmp_" + itostr(Slot) + "_" + utostr(V->getType()->getUniqueID());
}
// A pointer type should not use parens around *'s alone, e.g., (**)
inline bool ptrTypeNameNeedsParens(const string &NameSoFar) {
return (NameSoFar.find_last_not_of('*') != std::string::npos);
}
// Pass the Type* and the variable name and this prints out the variable
// declaration.
//
ostream &CWriter::printType(const Type *Ty, const string &NameSoFar,
bool IgnoreName, bool namedContext) {
if (Ty->isPrimitiveType())
switch (Ty->getPrimitiveID()) {
case Type::VoidTyID: return Out << "void " << NameSoFar;
case Type::BoolTyID: return Out << "bool " << NameSoFar;
case Type::UByteTyID: return Out << "unsigned char " << NameSoFar;
case Type::SByteTyID: return Out << "signed char " << NameSoFar;
case Type::UShortTyID: return Out << "unsigned short " << NameSoFar;
case Type::ShortTyID: return Out << "short " << NameSoFar;
case Type::UIntTyID: return Out << "unsigned " << NameSoFar;
case Type::IntTyID: return Out << "int " << NameSoFar;
case Type::ULongTyID: return Out << "unsigned long long " << NameSoFar;
case Type::LongTyID: return Out << "signed long long " << NameSoFar;
case Type::FloatTyID: return Out << "float " << NameSoFar;
case Type::DoubleTyID: return Out << "double " << NameSoFar;
default :
std::cerr << "Unknown primitive type: " << Ty << "\n";
abort();
}
// Check to see if the type is named.
if (!IgnoreName || isa<OpaqueType>(Ty)) {
map<const Type *, string>::iterator I = TypeNames.find(Ty);
if (I != TypeNames.end()) {
return Out << I->second << " " << NameSoFar;
}
}
switch (Ty->getPrimitiveID()) {
case Type::FunctionTyID: {
const FunctionType *MTy = cast<FunctionType>(Ty);
printType(MTy->getReturnType(), "");
Out << " (" << NameSoFar << ") (";
for (FunctionType::ParamTypes::const_iterator
I = MTy->getParamTypes().begin(),
E = MTy->getParamTypes().end(); I != E; ++I) {
if (I != MTy->getParamTypes().begin())
Out << ", ";
printType(*I, "");
}
if (MTy->isVarArg()) {
if (!MTy->getParamTypes().empty())
Out << ", ";
Out << "...";
}
return Out << ")";
}
case Type::StructTyID: {
const StructType *STy = cast<StructType>(Ty);
Out << NameSoFar + " {\n";
unsigned Idx = 0;
for (StructType::ElementTypes::const_iterator
I = STy->getElementTypes().begin(),
E = STy->getElementTypes().end(); I != E; ++I) {
Out << " ";
printType(*I, "field" + utostr(Idx++));
Out << ";\n";
}
return Out << "}";
}
case Type::PointerTyID: {
const PointerType *PTy = cast<PointerType>(Ty);
std::string ptrName = "*" + NameSoFar;
// Do not need parens around "* NameSoFar" if NameSoFar consists only
// of zero or more '*' chars *and* this is not an unnamed pointer type
// such as the result type in a cast statement. Otherwise, enclose in ( ).
if (ptrTypeNameNeedsParens(NameSoFar) || !namedContext ||
PTy->getElementType()->getPrimitiveID() == Type::ArrayTyID)
ptrName = "(" + ptrName + ")"; //
return printType(PTy->getElementType(), ptrName);
}
case Type::ArrayTyID: {
const ArrayType *ATy = cast<ArrayType>(Ty);
unsigned NumElements = ATy->getNumElements();
return printType(ATy->getElementType(),
NameSoFar + "[" + utostr(NumElements) + "]");
}
case Type::OpaqueTyID: {
static int Count = 0;
string TyName = "struct opaque_" + itostr(Count++);
assert(TypeNames.find(Ty) == TypeNames.end());
TypeNames[Ty] = TyName;
return Out << TyName << " " << NameSoFar;
}
default:
assert(0 && "Unhandled case in getTypeProps!");
abort();
}
return Out;
}
void CWriter::printConstantArray(ConstantArray *CPA) {
// As a special case, print the array as a string if it is an array of
// ubytes or an array of sbytes with positive values.
//
const Type *ETy = CPA->getType()->getElementType();
bool isString = (ETy == Type::SByteTy || ETy == Type::UByteTy);
// Make sure the last character is a null char, as automatically added by C
if (CPA->getNumOperands() == 0 ||
!cast<Constant>(*(CPA->op_end()-1))->isNullValue())
isString = false;
if (isString) {
Out << "\"";
// Do not include the last character, which we know is null
for (unsigned i = 0, e = CPA->getNumOperands()-1; i != e; ++i) {
unsigned char C = (ETy == Type::SByteTy) ?
(unsigned char)cast<ConstantSInt>(CPA->getOperand(i))->getValue() :
(unsigned char)cast<ConstantUInt>(CPA->getOperand(i))->getValue();
if (isprint(C)) {
if (C == '"' || C == '\\')
Out << "\\" << C;
else
Out << C;
} else {
switch (C) {
case '\n': Out << "\\n"; break;
case '\t': Out << "\\t"; break;
case '\r': Out << "\\r"; break;
case '\v': Out << "\\v"; break;
case '\a': Out << "\\a"; break;
case '\"': Out << "\\\""; break;
case '\'': Out << "\\\'"; break;
default:
Out << "\\x";
Out << ( C/16 < 10) ? ( C/16 +'0') : ( C/16 -10+'A');
Out << ((C&15) < 10) ? ((C&15)+'0') : ((C&15)-10+'A');
break;
}
}
}
Out << "\"";
} else {
Out << "{";
if (CPA->getNumOperands()) {
Out << " ";
printConstant(cast<Constant>(CPA->getOperand(0)));
for (unsigned i = 1, e = CPA->getNumOperands(); i != e; ++i) {
Out << ", ";
printConstant(cast<Constant>(CPA->getOperand(i)));
}
}
Out << " }";
}
}
// printConstant - The LLVM Constant to C Constant converter.
void CWriter::printConstant(Constant *CPV) {
if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CPV)) {
switch (CE->getOpcode()) {
case Instruction::Cast:
Out << "((";
printType(CPV->getType());
Out << ")";
printConstant(cast<Constant>(CPV->getOperand(0)));
Out << ")";
return;
case Instruction::GetElementPtr:
Out << "(&(";
printIndexingExpression(CPV->getOperand(0),
CPV->op_begin()+1, CPV->op_end());
Out << "))";
return;
case Instruction::Add:
Out << "(";
printConstant(cast<Constant>(CPV->getOperand(0)));
Out << " + ";
printConstant(cast<Constant>(CPV->getOperand(1)));
Out << ")";
return;
case Instruction::Sub:
Out << "(";
printConstant(cast<Constant>(CPV->getOperand(0)));
Out << " - ";
printConstant(cast<Constant>(CPV->getOperand(1)));
Out << ")";
return;
default:
std::cerr << "CWriter Error: Unhandled constant expression: "
<< CE << "\n";
abort();
}
}
switch (CPV->getType()->getPrimitiveID()) {
case Type::BoolTyID:
Out << (CPV == ConstantBool::False ? "0" : "1"); break;
case Type::SByteTyID:
case Type::ShortTyID:
case Type::IntTyID:
Out << cast<ConstantSInt>(CPV)->getValue(); break;
case Type::LongTyID:
Out << cast<ConstantSInt>(CPV)->getValue() << "ll"; break;
case Type::UByteTyID:
case Type::UShortTyID:
Out << cast<ConstantUInt>(CPV)->getValue(); break;
case Type::UIntTyID:
Out << cast<ConstantUInt>(CPV)->getValue() << "u"; break;
case Type::ULongTyID:
Out << cast<ConstantUInt>(CPV)->getValue() << "ull"; break;
case Type::FloatTyID:
case Type::DoubleTyID: {
ConstantFP *FPC = cast<ConstantFP>(CPV);
map<const ConstantFP *, unsigned>::iterator I = FPConstantMap.find(FPC);
if (I != FPConstantMap.end()) {
// Because of FP precision problems we must load from a stack allocated
// value that holds the value in hex.
Out << "(*(" << (FPC->getType() == Type::FloatTy ? "float" : "double")
<< "*)&FloatConstant" << I->second << ")";
} else {
Out << FPC->getValue();
}
break;
}
case Type::ArrayTyID:
printConstantArray(cast<ConstantArray>(CPV));
break;
case Type::StructTyID: {
Out << "{";
if (CPV->getNumOperands()) {
Out << " ";
printConstant(cast<Constant>(CPV->getOperand(0)));
for (unsigned i = 1, e = CPV->getNumOperands(); i != e; ++i) {
Out << ", ";
printConstant(cast<Constant>(CPV->getOperand(i)));
}
}
Out << " }";
break;
}
case Type::PointerTyID:
if (isa<ConstantPointerNull>(CPV)) {
Out << "(NULL)";
break;
} else if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(CPV)) {
writeOperand(CPR->getValue());
break;
}
// FALL THROUGH
default:
std::cerr << "Unknown constant type: " << CPV << "\n";
abort();
}
}
void CWriter::writeOperandInternal(Value *Operand) {
if (Instruction *I = dyn_cast<Instruction>(Operand))
if (isInlinableInst(*I)) {
// Should we inline this instruction to build a tree?
Out << "(";
visit(*I);
Out << ")";
return;
}
if (Operand->hasName()) {
Out << getValueName(Operand);
} else if (Constant *CPV = dyn_cast<Constant>(Operand)) {
printConstant(CPV);
} else {
int Slot = Table->getValSlot(Operand);
assert(Slot >= 0 && "Malformed LLVM!");
Out << "ltmp_" << Slot << "_" << Operand->getType()->getUniqueID();
}
}
void CWriter::writeOperand(Value *Operand) {
if (isa<GlobalVariable>(Operand))
Out << "(&"; // Global variables are references as their addresses by llvm
writeOperandInternal(Operand);
if (isa<GlobalVariable>(Operand))
Out << ")";
}
// nameAllUsedStructureTypes - If there are structure types in the module that
// are used but do not have names assigned to them in the symbol table yet then
// we assign them names now.
//
bool CWriter::nameAllUsedStructureTypes(Module &M) {
// Get a set of types that are used by the program...
std::set<const Type *> UT = getAnalysis<FindUsedTypes>().getTypes();
// Loop over the module symbol table, removing types from UT that are already
// named.
//
SymbolTable *MST = M.getSymbolTableSure();
if (MST->find(Type::TypeTy) != MST->end())
for (SymbolTable::type_iterator I = MST->type_begin(Type::TypeTy),
E = MST->type_end(Type::TypeTy); I != E; ++I)
UT.erase(cast<Type>(I->second));
// UT now contains types that are not named. Loop over it, naming structure
// types.
//
bool Changed = false;
for (std::set<const Type *>::const_iterator I = UT.begin(), E = UT.end();
I != E; ++I)
if (const StructType *ST = dyn_cast<StructType>(*I)) {
((Value*)ST)->setName("unnamed", MST);
Changed = true;
}
return Changed;
}
void CWriter::printModule(Module *M) {
// Calculate which global values have names that will collide when we throw
// away type information.
{ // Scope to delete the FoundNames set when we are done with it...
std::set<string> FoundNames;
for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
if (I->hasName()) // If the global has a name...
if (FoundNames.count(I->getName())) // And the name is already used
MangledGlobals.insert(I); // Mangle the name
else
FoundNames.insert(I->getName()); // Otherwise, keep track of name
for (Module::giterator I = M->gbegin(), E = M->gend(); I != E; ++I)
if (I->hasName()) // If the global has a name...
if (FoundNames.count(I->getName())) // And the name is already used
MangledGlobals.insert(I); // Mangle the name
else
FoundNames.insert(I->getName()); // Otherwise, keep track of name
}
// printing stdlib inclusion
//Out << "#include <stdlib.h>\n";
// get declaration for alloca
Out << "/* Provide Declarations */\n"
<< "#include <alloca.h>\n\n"
// Provide a definition for null if one does not already exist,
// and for `bool' if not compiling with a C++ compiler.
<< "#ifndef NULL\n#define NULL 0\n#endif\n\n"
<< "#ifndef __cplusplus\ntypedef unsigned char bool;\n#endif\n"
<< "\n\n/* Support for floating point constants */\n"
<< "typedef unsigned long long ConstantDoubleTy;\n"
<< "\n\n/* Global Declarations */\n";
// First output all the declarations for the program, because C requires
// Functions & globals to be declared before they are used.
//
// Loop over the symbol table, emitting all named constants...
if (M->hasSymbolTable())
printSymbolTable(*M->getSymbolTable());
// Global variable declarations...
if (!M->gempty()) {
Out << "\n/* External Global Variable Declarations */\n";
for (Module::giterator I = M->gbegin(), E = M->gend(); I != E; ++I) {
if (I->hasExternalLinkage()) {
Out << "extern ";
printType(I->getType()->getElementType(), getValueName(I));
Out << ";\n";
}
}
}
// Function declarations
if (!M->empty()) {
Out << "\n/* Function Declarations */\n";
needsMalloc = true;
for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) {
printFunctionSignature(I, true);
Out << ";\n";
}
}
// Print Malloc prototype if needed
if (needsMalloc){
Out << "\n/* Malloc to make sun happy */\n";
Out << "extern void * malloc(size_t);\n\n";
}
// Output the global variable declerations
if (!M->gempty()) {
Out << "\n\n/* Global Variable Declerations */\n";
for (Module::giterator I = M->gbegin(), E = M->gend(); I != E; ++I)
if (!I->isExternal()) {
Out << "extern ";
printType(I->getType()->getElementType(), getValueName(I));
Out << ";\n";
}
}
// Output the global variable definitions and contents...
if (!M->gempty()) {
Out << "\n\n/* Global Variable Definitions and Initialization */\n";
for (Module::giterator I = M->gbegin(), E = M->gend(); I != E; ++I)
if (!I->isExternal()) {
if (I->hasInternalLinkage())
Out << "static ";
printType(I->getType()->getElementType(), getValueName(I));
Out << " = " ;
writeOperand(I->getInitializer());
Out << ";\n";
}
}
// Output all of the functions...
if (!M->empty()) {
Out << "\n\n/* Function Bodies */\n";
for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
printFunction(I);
}
}
/// printSymbolTable - Run through symbol table looking for type names. If a
/// type name is found, emit it's declaration...
///
void CWriter::printSymbolTable(const SymbolTable &ST) {
// If there are no type names, exit early.
if (ST.find(Type::TypeTy) == ST.end())
return;
// We are only interested in the type plane of the symbol table...
SymbolTable::type_const_iterator I = ST.type_begin(Type::TypeTy);
SymbolTable::type_const_iterator End = ST.type_end(Type::TypeTy);
// Print out forward declarations for structure types before anything else!
Out << "/* Structure forward decls */\n";
for (; I != End; ++I)
if (const Type *STy = dyn_cast<StructType>(I->second)) {
string Name = "struct l_" + makeNameProper(I->first);
Out << Name << ";\n";
TypeNames.insert(std::make_pair(STy, Name));
}
Out << "\n";
// Now we can print out typedefs...
Out << "/* Typedefs */\n";
for (I = ST.type_begin(Type::TypeTy); I != End; ++I) {
const Type *Ty = cast<Type>(I->second);
string Name = "l_" + makeNameProper(I->first);
Out << "typedef ";
printType(Ty, Name);
Out << ";\n";
}
Out << "\n";
// Keep track of which structures have been printed so far...
std::set<const StructType *> StructPrinted;
// Loop over all structures then push them into the stack so they are
// printed in the correct order.
//
Out << "/* Structure contents */\n";
for (I = ST.type_begin(Type::TypeTy); I != End; ++I)
if (const StructType *STy = dyn_cast<StructType>(I->second))
printContainedStructs(STy, StructPrinted);
}
// Push the struct onto the stack and recursively push all structs
// this one depends on.
void CWriter::printContainedStructs(const Type *Ty,
std::set<const StructType*> &StructPrinted){
if (const StructType *STy = dyn_cast<StructType>(Ty)){
//Check to see if we have already printed this struct
if (StructPrinted.count(STy) == 0) {
// Print all contained types first...
for (StructType::ElementTypes::const_iterator
I = STy->getElementTypes().begin(),
E = STy->getElementTypes().end(); I != E; ++I) {
const Type *Ty1 = I->get();
if (isa<StructType>(Ty1) || isa<ArrayType>(Ty1))
printContainedStructs(Ty1, StructPrinted);
}
//Print structure type out..
StructPrinted.insert(STy);
string Name = TypeNames[STy];
printType(STy, Name, true);
Out << ";\n\n";
}
// If it is an array, check contained types and continue
} else if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)){
const Type *Ty1 = ATy->getElementType();
if (isa<StructType>(Ty1) || isa<ArrayType>(Ty1))
printContainedStructs(Ty1, StructPrinted);
}
}
void CWriter::printFunctionSignature(const Function *F, bool Prototype) {
// If the program provides it's own malloc prototype we don't need
// to include the general one.
if (getValueName(F) == "malloc")
needsMalloc = false;
if (F->hasInternalLinkage()) Out << "static ";
// Loop over the arguments, printing them...
const FunctionType *FT = cast<FunctionType>(F->getFunctionType());
// Print out the return type and name...
printType(F->getReturnType());
Out << getValueName(F) << "(";
if (!F->isExternal()) {
if (!F->aempty()) {
string ArgName;
if (F->abegin()->hasName() || !Prototype)
ArgName = getValueName(F->abegin());
printType(F->afront().getType(), ArgName);
for (Function::const_aiterator I = ++F->abegin(), E = F->aend();
I != E; ++I) {
Out << ", ";
if (I->hasName() || !Prototype)
ArgName = getValueName(I);
else
ArgName = "";
printType(I->getType(), ArgName);
}
}
} else {
// Loop over the arguments, printing them...
for (FunctionType::ParamTypes::const_iterator I =
FT->getParamTypes().begin(),
E = FT->getParamTypes().end(); I != E; ++I) {
if (I != FT->getParamTypes().begin()) Out << ", ";
printType(*I);
}
}
// Finish printing arguments... if this is a vararg function, print the ...,
// unless there are no known types, in which case, we just emit ().
//
if (FT->isVarArg() && !FT->getParamTypes().empty()) {
if (FT->getParamTypes().size()) Out << ", ";
Out << "..."; // Output varargs portion of signature!
}
Out << ")";
}
void CWriter::printFunction(Function *F) {
if (F->isExternal()) return;
Table->incorporateFunction(F);
printFunctionSignature(F, false);
Out << " {\n";
// print local variable information for the function
for (inst_iterator I = inst_begin(F), E = inst_end(F); I != E; ++I)
if ((*I)->getType() != Type::VoidTy && !isInlinableInst(**I)) {
Out << " ";
printType((*I)->getType(), getValueName(*I));
Out << ";\n";
}
Out << "\n";
// Scan the function for floating point constants. If any FP constant is used
// in the function, we want to redirect it here so that we do not depend on
// the precision of the printed form.
//
unsigned FPCounter = 0;
for (constant_iterator I = constant_begin(F), E = constant_end(F); I != E;++I)
if (const ConstantFP *FPC = dyn_cast<ConstantFP>(*I))
if (FPConstantMap.find(FPC) == FPConstantMap.end()) {
double Val = FPC->getValue();
FPConstantMap[FPC] = FPCounter; // Number the FP constants
Out << " const ConstantDoubleTy FloatConstant" << FPCounter++
<< " = 0x" << std::hex << *(unsigned long long*)&Val << std::dec
<< "; /* " << Val << " */\n";
}
Out << "\n";
// print the basic blocks
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
BasicBlock *Prev = BB->getPrev();
// Don't print the label for the basic block if there are no uses, or if the
// only terminator use is the precessor basic block's terminator. We have
// to scan the use list because PHI nodes use basic blocks too but do not
// require a label to be generated.
//
bool NeedsLabel = false;
for (Value::use_iterator UI = BB->use_begin(), UE = BB->use_end();
UI != UE; ++UI)
if (TerminatorInst *TI = dyn_cast<TerminatorInst>(*UI))
if (TI != Prev->getTerminator()) {
NeedsLabel = true;
break;
}
if (NeedsLabel) Out << getValueName(BB) << ":\n";
// Output all of the instructions in the basic block...
for (BasicBlock::iterator II = BB->begin(), E = --BB->end(); II != E; ++II){
if (!isInlinableInst(*II) && !isa<PHINode>(*II)) {
if (II->getType() != Type::VoidTy)
outputLValue(II);
else
Out << " ";
visit(*II);
Out << ";\n";
}
}
// Don't emit prefix or suffix for the terminator...
visit(*BB->getTerminator());
}
Out << "}\n\n";
Table->purgeFunction();
FPConstantMap.clear();
}
// Specific Instruction type classes... note that all of the casts are
// neccesary because we use the instruction classes as opaque types...
//
void CWriter::visitReturnInst(ReturnInst &I) {
// Don't output a void return if this is the last basic block in the function
if (I.getNumOperands() == 0 &&
&*--I.getParent()->getParent()->end() == I.getParent() &&
!I.getParent()->size() == 1) {
return;
}
Out << " return";
if (I.getNumOperands()) {
Out << " ";
writeOperand(I.getOperand(0));
}
Out << ";\n";
}
static bool isGotoCodeNeccessary(BasicBlock *From, BasicBlock *To) {
// If PHI nodes need copies, we need the copy code...
if (isa<PHINode>(To->front()) ||
From->getNext() != To) // Not directly successor, need goto
return true;
// Otherwise we don't need the code.
return false;
}
void CWriter::printBranchToBlock(BasicBlock *CurBB, BasicBlock *Succ,
unsigned Indent) {
for (BasicBlock::iterator I = Succ->begin();
PHINode *PN = dyn_cast<PHINode>(&*I); ++I) {
// now we have to do the printing
Out << string(Indent, ' ');
outputLValue(PN);
writeOperand(PN->getIncomingValue(PN->getBasicBlockIndex(CurBB)));
Out << "; /* for PHI node */\n";
}
if (CurBB->getNext() != Succ) {
Out << string(Indent, ' ') << " goto ";
writeOperand(Succ);
Out << ";\n";
}
}
// Brach instruction printing - Avoid printing out a brach to a basic block that
// immediately succeeds the current one.
//
void CWriter::visitBranchInst(BranchInst &I) {
if (I.isConditional()) {
if (isGotoCodeNeccessary(I.getParent(), I.getSuccessor(0))) {
Out << " if (";
writeOperand(I.getCondition());
Out << ") {\n";
printBranchToBlock(I.getParent(), I.getSuccessor(0), 2);
if (isGotoCodeNeccessary(I.getParent(), I.getSuccessor(1))) {
Out << " } else {\n";
printBranchToBlock(I.getParent(), I.getSuccessor(1), 2);
}
} else {
// First goto not neccesary, assume second one is...
Out << " if (!";
writeOperand(I.getCondition());
Out << ") {\n";
printBranchToBlock(I.getParent(), I.getSuccessor(1), 2);
}
Out << " }\n";
} else {
printBranchToBlock(I.getParent(), I.getSuccessor(0), 0);
}
Out << "\n";
}
void CWriter::visitBinaryOperator(Instruction &I) {
// binary instructions, shift instructions, setCond instructions.
if (isa<PointerType>(I.getType())) {
Out << "(";
printType(I.getType());
Out << ")";
}
if (isa<PointerType>(I.getType())) Out << "(long long)";
writeOperand(I.getOperand(0));
switch (I.getOpcode()) {
case Instruction::Add: Out << " + "; break;
case Instruction::Sub: Out << " - "; break;
case Instruction::Mul: Out << "*"; break;
case Instruction::Div: Out << "/"; break;
case Instruction::Rem: Out << "%"; break;
case Instruction::And: Out << " & "; break;
case Instruction::Or: Out << " | "; break;
case Instruction::Xor: Out << " ^ "; break;
case Instruction::SetEQ: Out << " == "; break;
case Instruction::SetNE: Out << " != "; break;
case Instruction::SetLE: Out << " <= "; break;
case Instruction::SetGE: Out << " >= "; break;
case Instruction::SetLT: Out << " < "; break;
case Instruction::SetGT: Out << " > "; break;
case Instruction::Shl : Out << " << "; break;
case Instruction::Shr : Out << " >> "; break;
default: std::cerr << "Invalid operator type!" << I; abort();
}
if (isa<PointerType>(I.getType())) Out << "(long long)";
writeOperand(I.getOperand(1));
}
void CWriter::visitCastInst(CastInst &I) {
Out << "(";
printType(I.getType(), string(""),/*ignoreName*/false, /*namedContext*/false);
Out << ")";
writeOperand(I.getOperand(0));
}
void CWriter::visitCallInst(CallInst &I) {
const PointerType *PTy = cast<PointerType>(I.getCalledValue()->getType());
const FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
const Type *RetTy = FTy->getReturnType();
writeOperand(I.getOperand(0));
Out << "(";
if (I.getNumOperands() > 1) {
writeOperand(I.getOperand(1));
for (unsigned op = 2, Eop = I.getNumOperands(); op != Eop; ++op) {
Out << ", ";
writeOperand(I.getOperand(op));
}
}
Out << ")";
}
void CWriter::visitMallocInst(MallocInst &I) {
Out << "(";
printType(I.getType());
Out << ")malloc(sizeof(";
printType(I.getType()->getElementType());
Out << ")";
if (I.isArrayAllocation()) {
Out << " * " ;
writeOperand(I.getOperand(0));
}
Out << ")";
}
void CWriter::visitAllocaInst(AllocaInst &I) {
Out << "(";
printType(I.getType());
Out << ") alloca(sizeof(";
printType(I.getType()->getElementType());
Out << ")";
if (I.isArrayAllocation()) {
Out << " * " ;
writeOperand(I.getOperand(0));
}
Out << ")";
}
void CWriter::visitFreeInst(FreeInst &I) {
Out << "free(";
writeOperand(I.getOperand(0));
Out << ")";
}
void CWriter::printIndexingExpression(Value *Ptr, User::op_iterator I,
User::op_iterator E) {
bool HasImplicitAddress = false;
// If accessing a global value with no indexing, avoid *(&GV) syndrome
if (GlobalValue *V = dyn_cast<GlobalValue>(Ptr)) {
HasImplicitAddress = true;
} else if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(Ptr)) {
HasImplicitAddress = true;
Ptr = CPR->getValue(); // Get to the global...
}
if (I == E) {
if (!HasImplicitAddress)
Out << "*"; // Implicit zero first argument: '*x' is equivalent to 'x[0]'
writeOperandInternal(Ptr);
return;
}
const Constant *CI = dyn_cast<Constant>(I->get());
if (HasImplicitAddress && (!CI || !CI->isNullValue()))
Out << "(&";
writeOperandInternal(Ptr);
if (HasImplicitAddress && (!CI || !CI->isNullValue())) {
Out << ")";
HasImplicitAddress = false; // HIA is only true if we haven't addressed yet
}
assert(!HasImplicitAddress || (CI && CI->isNullValue()) &&
"Can only have implicit address with direct accessing");
if (HasImplicitAddress) {
++I;
} else if (CI && CI->isNullValue() && I+1 != E) {
// Print out the -> operator if possible...
if ((*(I+1))->getType() == Type::UByteTy) {
Out << (HasImplicitAddress ? "." : "->");
Out << "field" << cast<ConstantUInt>(*(I+1))->getValue();
I += 2;
}
}
for (; I != E; ++I)
if ((*I)->getType() == Type::LongTy) {
Out << "[";
writeOperand(*I);
Out << "]";
} else {
Out << ".field" << cast<ConstantUInt>(*I)->getValue();
}
}
void CWriter::visitLoadInst(LoadInst &I) {
Out << "*";
writeOperand(I.getOperand(0));
}
void CWriter::visitStoreInst(StoreInst &I) {
Out << "*";
writeOperand(I.getPointerOperand());
Out << " = ";
writeOperand(I.getOperand(0));
}
void CWriter::visitGetElementPtrInst(GetElementPtrInst &I) {
Out << "&";
printIndexingExpression(I.getPointerOperand(), I.idx_begin(), I.idx_end());
}
//===----------------------------------------------------------------------===//
// External Interface declaration
//===----------------------------------------------------------------------===//
Pass *createWriteToCPass(std::ostream &o) { return new CWriter(o); }
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