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 << (uint64_t)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, possibly
73 // decorating it with GlobalVarAddrPrefix/Suffix or
74 // FunctionAddrPrefix/Suffix (these all default to "" )
75 if (isa<Function>((Value*)CV))
76 O << FunctionAddrPrefix << Mang->getValueName(CV) << FunctionAddrSuffix;
78 O << GlobalVarAddrPrefix << Mang->getValueName(CV) << GlobalVarAddrSuffix;
79 } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
80 const TargetData &TD = TM.getTargetData();
81 switch(CE->getOpcode()) {
82 case Instruction::GetElementPtr: {
83 // generate a symbolic expression for the byte address
84 const Constant *ptrVal = CE->getOperand(0);
85 std::vector<Value*> idxVec(CE->op_begin()+1, CE->op_end());
86 if (int64_t Offset = TD.getIndexedOffset(ptrVal->getType(), idxVec)) {
89 emitConstantValueOnly(ptrVal);
91 O << ") + " << Offset;
93 O << ") - " << -Offset;
95 emitConstantValueOnly(ptrVal);
99 case Instruction::Cast: {
100 // Support only non-converting or widening casts for now, that is, ones
101 // that do not involve a change in value. This assertion is really gross,
102 // and may not even be a complete check.
103 Constant *Op = CE->getOperand(0);
104 const Type *OpTy = Op->getType(), *Ty = CE->getType();
106 // Remember, kids, pointers can be losslessly converted back and forth
107 // into 32-bit or wider integers, regardless of signedness. :-P
108 assert(((isa<PointerType>(OpTy)
109 && (Ty == Type::LongTy || Ty == Type::ULongTy
110 || Ty == Type::IntTy || Ty == Type::UIntTy))
111 || (isa<PointerType>(Ty)
112 && (OpTy == Type::LongTy || OpTy == Type::ULongTy
113 || OpTy == Type::IntTy || OpTy == Type::UIntTy))
114 || (((TD.getTypeSize(Ty) >= TD.getTypeSize(OpTy))
115 && OpTy->isLosslesslyConvertibleTo(Ty))))
116 && "FIXME: Don't yet support this kind of constant cast expr");
118 emitConstantValueOnly(Op);
122 case Instruction::Add:
124 emitConstantValueOnly(CE->getOperand(0));
126 emitConstantValueOnly(CE->getOperand(1));
130 assert(0 && "Unsupported operator!");
133 assert(0 && "Unknown constant value!");
137 /// toOctal - Convert the low order bits of X into an octal digit.
139 static inline char toOctal(int X) {
143 /// getAsCString - Return the specified array as a C compatible string, only if
144 /// the predicate isString is true.
146 static void printAsCString(std::ostream &O, const ConstantArray *CVA) {
147 assert(CVA->isString() && "Array is not string compatible!");
150 for (unsigned i = 0; i != CVA->getNumOperands(); ++i) {
152 (unsigned char)cast<ConstantInt>(CVA->getOperand(i))->getRawValue();
156 } else if (C == '\\') {
158 } else if (isprint(C)) {
162 case '\b': O << "\\b"; break;
163 case '\f': O << "\\f"; break;
164 case '\n': O << "\\n"; break;
165 case '\r': O << "\\r"; break;
166 case '\t': O << "\\t"; break;
169 O << toOctal(C >> 6);
170 O << toOctal(C >> 3);
171 O << toOctal(C >> 0);
179 /// emitGlobalConstant - Print a general LLVM constant to the .s file.
181 void AsmPrinter::emitGlobalConstant(const Constant *CV) {
182 const TargetData &TD = TM.getTargetData();
184 if (CV->isNullValue() || isa<UndefValue>(CV)) {
185 emitZeros(TD.getTypeSize(CV->getType()));
187 } else if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
188 if (CVA->isString()) {
190 printAsCString(O, CVA);
192 } else { // Not a string. Print the values in successive locations
193 for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i)
194 emitGlobalConstant(CVA->getOperand(i));
197 } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
198 // Print the fields in successive locations. Pad to align if needed!
199 const StructLayout *cvsLayout = TD.getStructLayout(CVS->getType());
200 uint64_t sizeSoFar = 0;
201 for (unsigned i = 0, e = CVS->getNumOperands(); i != e; ++i) {
202 const Constant* field = CVS->getOperand(i);
204 // Check if padding is needed and insert one or more 0s.
205 uint64_t fieldSize = TD.getTypeSize(field->getType());
206 uint64_t padSize = ((i == e-1? cvsLayout->StructSize
207 : cvsLayout->MemberOffsets[i+1])
208 - cvsLayout->MemberOffsets[i]) - fieldSize;
209 sizeSoFar += fieldSize + padSize;
211 // Now print the actual field value
212 emitGlobalConstant(field);
214 // Insert the field padding unless it's zero bytes...
217 assert(sizeSoFar == cvsLayout->StructSize &&
218 "Layout of constant struct may be incorrect!");
220 } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
221 // FP Constants are printed as integer constants to avoid losing
223 double Val = CFP->getValue();
224 if (CFP->getType() == Type::DoubleTy) {
225 union DU { // Abide by C TBAA rules
231 if (Data64bitsDirective)
232 O << Data64bitsDirective << U.UVal << "\t" << CommentString
233 << " double value: " << Val << "\n";
234 else if (TD.isBigEndian()) {
235 O << Data32bitsDirective << unsigned(U.UVal >> 32)
236 << "\t" << CommentString << " double most significant word "
238 O << Data32bitsDirective << unsigned(U.UVal)
239 << "\t" << CommentString << " double least significant word "
242 O << Data32bitsDirective << unsigned(U.UVal)
243 << "\t" << CommentString << " double least significant word " << Val
245 O << Data32bitsDirective << unsigned(U.UVal >> 32)
246 << "\t" << CommentString << " double most significant word " << Val
251 union FU { // Abide by C TBAA rules
257 O << Data32bitsDirective << U.UVal << "\t" << CommentString
258 << " float " << Val << "\n";
261 } else if (CV->getType() == Type::ULongTy || CV->getType() == Type::LongTy) {
262 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
263 uint64_t Val = CI->getRawValue();
265 if (Data64bitsDirective)
266 O << Data64bitsDirective << Val << "\n";
267 else if (TD.isBigEndian()) {
268 O << Data32bitsDirective << unsigned(Val >> 32)
269 << "\t" << CommentString << " Double-word most significant word "
271 O << Data32bitsDirective << unsigned(Val)
272 << "\t" << CommentString << " Double-word least significant word "
275 O << Data32bitsDirective << unsigned(Val)
276 << "\t" << CommentString << " Double-word least significant word "
278 O << Data32bitsDirective << unsigned(Val >> 32)
279 << "\t" << CommentString << " Double-word most significant word "
286 const Type *type = CV->getType();
287 switch (type->getTypeID()) {
289 case Type::UByteTyID: case Type::SByteTyID:
290 O << Data8bitsDirective;
292 case Type::UShortTyID: case Type::ShortTyID:
293 O << Data16bitsDirective;
295 case Type::PointerTyID:
296 if (TD.getPointerSize() == 8) {
297 O << Data64bitsDirective;
300 //Fall through for pointer size == int size
301 case Type::UIntTyID: case Type::IntTyID:
302 O << Data32bitsDirective;
304 case Type::ULongTyID: case Type::LongTyID:
305 assert (0 && "Should have already output double-word constant.");
306 case Type::FloatTyID: case Type::DoubleTyID:
307 assert (0 && "Should have already output floating point constant.");
309 assert (0 && "Can't handle printing this type of thing");
312 emitConstantValueOnly(CV);