1 //===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===//
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 file implements the AsmPrinter class.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/CodeGen/AsmPrinter.h"
15 #include "llvm/Constants.h"
16 #include "llvm/Instruction.h"
17 #include "llvm/Support/Mangler.h"
18 #include "llvm/Target/TargetMachine.h"
21 bool AsmPrinter::doInitialization(Module &M) {
22 Mang = new Mangler(M, GlobalPrefix);
26 bool AsmPrinter::doFinalization(Module &M) {
27 delete Mang; Mang = 0;
31 void AsmPrinter::setupMachineFunction(MachineFunction &MF) {
32 // What's my mangled name?
33 CurrentFnName = Mang->getValueName((Value*)MF.getFunction());
36 // emitAlignment - Emit an alignment directive to the specified power of two.
37 void AsmPrinter::emitAlignment(unsigned NumBits) const {
38 if (AlignmentIsInBytes) NumBits = 1 << NumBits;
39 O << AlignDirective << NumBits << "\n";
42 /// emitZeros - Emit a block of zeros.
44 void AsmPrinter::emitZeros(uint64_t NumZeros) const {
47 O << ZeroDirective << NumZeros << "\n";
49 for (; NumZeros; --NumZeros)
50 O << Data8bitsDirective << "0\n";
55 // Print out the specified constant, without a storage class. Only the
56 // constants valid in constant expressions can occur here.
57 void AsmPrinter::emitConstantValueOnly(const Constant *CV) {
58 if (CV->isNullValue() || isa<UndefValue>(CV))
60 else if (const ConstantBool *CB = dyn_cast<ConstantBool>(CV)) {
61 assert(CB == ConstantBool::True);
63 } else if (const ConstantSInt *CI = dyn_cast<ConstantSInt>(CV))
64 if (((CI->getValue() << 32) >> 32) == CI->getValue())
67 O << (unsigned long long)CI->getValue();
68 else if (const ConstantUInt *CI = dyn_cast<ConstantUInt>(CV))
70 else if (isa<GlobalValue>((Value*)CV))
71 // This is a constant address for a global variable or function. Use the
72 // name of the variable or function as the address value.
73 O << Mang->getValueName(CV);
74 else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
75 const TargetData &TD = TM.getTargetData();
76 switch(CE->getOpcode()) {
77 case Instruction::GetElementPtr: {
78 // generate a symbolic expression for the byte address
79 const Constant *ptrVal = CE->getOperand(0);
80 std::vector<Value*> idxVec(CE->op_begin()+1, CE->op_end());
81 if (int64_t Offset = TD.getIndexedOffset(ptrVal->getType(), idxVec)) {
84 emitConstantValueOnly(ptrVal);
86 O << ") + " << Offset;
88 O << ") - " << -Offset;
90 emitConstantValueOnly(ptrVal);
94 case Instruction::Cast: {
95 // Support only non-converting or widening casts for now, that is, ones
96 // that do not involve a change in value. This assertion is really gross,
97 // and may not even be a complete check.
98 Constant *Op = CE->getOperand(0);
99 const Type *OpTy = Op->getType(), *Ty = CE->getType();
101 // Remember, kids, pointers can be losslessly converted back and forth
102 // into 32-bit or wider integers, regardless of signedness. :-P
103 assert(((isa<PointerType>(OpTy)
104 && (Ty == Type::LongTy || Ty == Type::ULongTy
105 || Ty == Type::IntTy || Ty == Type::UIntTy))
106 || (isa<PointerType>(Ty)
107 && (OpTy == Type::LongTy || OpTy == Type::ULongTy
108 || OpTy == Type::IntTy || OpTy == Type::UIntTy))
109 || (((TD.getTypeSize(Ty) >= TD.getTypeSize(OpTy))
110 && OpTy->isLosslesslyConvertibleTo(Ty))))
111 && "FIXME: Don't yet support this kind of constant cast expr");
113 emitConstantValueOnly(Op);
117 case Instruction::Add:
119 emitConstantValueOnly(CE->getOperand(0));
121 emitConstantValueOnly(CE->getOperand(1));
125 assert(0 && "Unsupported operator!");
128 assert(0 && "Unknown constant value!");
132 /// toOctal - Convert the low order bits of X into an octal digit.
134 static inline char toOctal(int X) {
138 /// getAsCString - Return the specified array as a C compatible string, only if
139 /// the predicate isString is true.
141 static void printAsCString(std::ostream &O, const ConstantArray *CVA) {
142 assert(CVA->isString() && "Array is not string compatible!");
145 for (unsigned i = 0; i != CVA->getNumOperands(); ++i) {
147 (unsigned char)cast<ConstantInt>(CVA->getOperand(i))->getRawValue();
151 } else if (C == '\\') {
153 } else if (isprint(C)) {
157 case '\b': O << "\\b"; break;
158 case '\f': O << "\\f"; break;
159 case '\n': O << "\\n"; break;
160 case '\r': O << "\\r"; break;
161 case '\t': O << "\\t"; break;
164 O << toOctal(C >> 6);
165 O << toOctal(C >> 3);
166 O << toOctal(C >> 0);
174 /// emitGlobalConstant - Print a general LLVM constant to the .s file.
176 void AsmPrinter::emitGlobalConstant(const Constant *CV) {
177 const TargetData &TD = TM.getTargetData();
179 if (CV->isNullValue() || isa<UndefValue>(CV)) {
180 emitZeros(TD.getTypeSize(CV->getType()));
182 } else if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
183 if (CVA->isString()) {
185 printAsCString(O, CVA);
187 } else { // Not a string. Print the values in successive locations
188 for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i)
189 emitGlobalConstant(CVA->getOperand(i));
192 } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
193 // Print the fields in successive locations. Pad to align if needed!
194 const StructLayout *cvsLayout = TD.getStructLayout(CVS->getType());
195 uint64_t sizeSoFar = 0;
196 for (unsigned i = 0, e = CVS->getNumOperands(); i != e; ++i) {
197 const Constant* field = CVS->getOperand(i);
199 // Check if padding is needed and insert one or more 0s.
200 uint64_t fieldSize = TD.getTypeSize(field->getType());
201 uint64_t padSize = ((i == e-1? cvsLayout->StructSize
202 : cvsLayout->MemberOffsets[i+1])
203 - cvsLayout->MemberOffsets[i]) - fieldSize;
204 sizeSoFar += fieldSize + padSize;
206 // Now print the actual field value
207 emitGlobalConstant(field);
209 // Insert the field padding unless it's zero bytes...
212 assert(sizeSoFar == cvsLayout->StructSize &&
213 "Layout of constant struct may be incorrect!");
215 } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
216 // FP Constants are printed as integer constants to avoid losing
218 double Val = CFP->getValue();
219 if (CFP->getType() == Type::DoubleTy) {
220 union DU { // Abide by C TBAA rules
226 if (Data64bitsDirective)
227 O << Data64bitsDirective << U.UVal << "\t" << CommentString
228 << " double value: " << Val << "\n";
229 else if (TD.isBigEndian()) {
230 O << Data32bitsDirective << unsigned(U.UVal >> 32)
231 << "\t" << CommentString << " double most significant word "
233 O << Data32bitsDirective << unsigned(U.UVal)
234 << "\t" << CommentString << " double least significant word "
237 O << Data32bitsDirective << unsigned(U.UVal)
238 << "\t" << CommentString << " double least significant word " << Val
240 O << Data32bitsDirective << unsigned(U.UVal >> 32)
241 << "\t" << CommentString << " double most significant word " << Val
246 union FU { // Abide by C TBAA rules
252 O << Data32bitsDirective << U.UVal << "\t" << CommentString
253 << " float " << Val << "\n";
256 } else if (CV->getType() == Type::ULongTy || CV->getType() == Type::LongTy) {
257 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
258 uint64_t Val = CI->getRawValue();
260 if (Data64bitsDirective)
261 O << Data64bitsDirective << Val << "\n";
262 else if (TD.isBigEndian()) {
263 O << Data32bitsDirective << unsigned(Val >> 32)
264 << "\t" << CommentString << " Double-word most significant word "
266 O << Data32bitsDirective << unsigned(Val)
267 << "\t" << CommentString << " Double-word least significant word "
270 O << Data32bitsDirective << unsigned(Val)
271 << "\t" << CommentString << " Double-word least significant word "
273 O << Data32bitsDirective << unsigned(Val >> 32)
274 << "\t" << CommentString << " Double-word most significant word "
281 const Type *type = CV->getType();
282 switch (type->getTypeID()) {
284 case Type::UByteTyID: case Type::SByteTyID:
285 O << Data8bitsDirective;
287 case Type::UShortTyID: case Type::ShortTyID:
288 O << Data16bitsDirective;
290 case Type::PointerTyID:
291 if (TD.getPointerSize() == 8) {
292 O << Data64bitsDirective;
295 //Fall through for pointer size == int size
296 case Type::UIntTyID: case Type::IntTyID:
297 O << Data32bitsDirective;
299 case Type::ULongTyID: case Type::LongTyID:
300 assert (0 && "Should have already output double-word constant.");
301 case Type::FloatTyID: case Type::DoubleTyID:
302 assert (0 && "Should have already output floating point constant.");
304 assert (0 && "Can't handle printing this type of thing");
307 emitConstantValueOnly(CV);