1 //===-- SparcV8AsmPrinter.cpp - SparcV8 LLVM assembly writer --------------===//
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 contains a printer that converts from our internal representation
11 // of machine-dependent LLVM code to GAS-format Sparc V8 assembly language.
13 //===----------------------------------------------------------------------===//
16 #include "SparcV8InstrInfo.h"
17 #include "llvm/Constants.h"
18 #include "llvm/DerivedTypes.h"
19 #include "llvm/Module.h"
20 #include "llvm/Assembly/Writer.h"
21 #include "llvm/CodeGen/MachineFunctionPass.h"
22 #include "llvm/CodeGen/MachineConstantPool.h"
23 #include "llvm/CodeGen/MachineInstr.h"
24 #include "llvm/Target/TargetMachine.h"
25 #include "llvm/Support/Mangler.h"
26 #include "Support/Statistic.h"
27 #include "Support/StringExtras.h"
28 #include "Support/CommandLine.h"
33 Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");
35 struct V8Printer : public MachineFunctionPass {
36 /// Output stream on which we're printing assembly code.
40 /// Target machine description which we query for reg. names, data
45 /// Name-mangler for global names.
49 V8Printer(std::ostream &o, TargetMachine &tm) : O(o), TM(tm) { }
51 /// We name each basic block in a Function with a unique number, so
52 /// that we can consistently refer to them later. This is cleared
53 /// at the beginning of each call to runOnMachineFunction().
55 typedef std::map<const Value *, unsigned> ValueMapTy;
56 ValueMapTy NumberForBB;
58 /// Cache of mangled name for current function. This is
59 /// recalculated at the beginning of each call to
60 /// runOnMachineFunction().
62 std::string CurrentFnName;
64 virtual const char *getPassName() const {
65 return "SparcV8 Assembly Printer";
68 void emitConstantValueOnly(const Constant *CV);
69 void emitGlobalConstant(const Constant *CV);
70 void printConstantPool(MachineConstantPool *MCP);
71 void printOperand(const MachineInstr *MI, int opNum);
72 void printBaseOffsetPair (const MachineInstr *MI, int i);
73 void printMachineInstruction(const MachineInstr *MI);
74 bool runOnMachineFunction(MachineFunction &F);
75 bool doInitialization(Module &M);
76 bool doFinalization(Module &M);
78 } // end of anonymous namespace
80 /// createSparcV8CodePrinterPass - Returns a pass that prints the SparcV8
81 /// assembly code for a MachineFunction to the given output stream,
82 /// using the given target machine description. This should work
83 /// regardless of whether the function is in SSA form.
85 FunctionPass *llvm::createSparcV8CodePrinterPass (std::ostream &o,
87 return new V8Printer(o, tm);
90 /// toOctal - Convert the low order bits of X into an octal digit.
92 static inline char toOctal(int X) {
96 /// getAsCString - Return the specified array as a C compatible
97 /// string, only if the predicate isStringCompatible is true.
99 static void printAsCString(std::ostream &O, const ConstantArray *CVA) {
100 assert(CVA->isString() && "Array is not string compatible!");
103 for (unsigned i = 0; i != CVA->getNumOperands(); ++i) {
104 unsigned char C = cast<ConstantInt>(CVA->getOperand(i))->getRawValue();
108 } else if (C == '\\') {
110 } else if (isprint(C)) {
114 case '\b': O << "\\b"; break;
115 case '\f': O << "\\f"; break;
116 case '\n': O << "\\n"; break;
117 case '\r': O << "\\r"; break;
118 case '\t': O << "\\t"; break;
121 O << toOctal(C >> 6);
122 O << toOctal(C >> 3);
123 O << toOctal(C >> 0);
131 // Print out the specified constant, without a storage class. Only the
132 // constants valid in constant expressions can occur here.
133 void V8Printer::emitConstantValueOnly(const Constant *CV) {
134 if (CV->isNullValue())
136 else if (const ConstantBool *CB = dyn_cast<ConstantBool>(CV)) {
137 assert(CB == ConstantBool::True);
139 } else if (const ConstantSInt *CI = dyn_cast<ConstantSInt>(CV))
140 if (((CI->getValue() << 32) >> 32) == CI->getValue())
143 O << (unsigned long long)CI->getValue();
144 else if (const ConstantUInt *CI = dyn_cast<ConstantUInt>(CV))
146 else if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(CV))
147 // This is a constant address for a global variable or function. Use the
148 // name of the variable or function as the address value.
149 O << Mang->getValueName(CPR->getValue());
150 else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
151 const TargetData &TD = TM.getTargetData();
152 switch(CE->getOpcode()) {
153 case Instruction::GetElementPtr: {
154 // generate a symbolic expression for the byte address
155 const Constant *ptrVal = CE->getOperand(0);
156 std::vector<Value*> idxVec(CE->op_begin()+1, CE->op_end());
157 if (unsigned Offset = TD.getIndexedOffset(ptrVal->getType(), idxVec)) {
159 emitConstantValueOnly(ptrVal);
160 O << ") + " << Offset;
162 emitConstantValueOnly(ptrVal);
166 case Instruction::Cast: {
167 // Support only non-converting or widening casts for now, that is, ones
168 // that do not involve a change in value. This assertion is really gross,
169 // and may not even be a complete check.
170 Constant *Op = CE->getOperand(0);
171 const Type *OpTy = Op->getType(), *Ty = CE->getType();
173 // Pointers on ILP32 machines can be losslessly converted back and
174 // forth into 32-bit or wider integers, regardless of signedness.
175 assert(((isa<PointerType>(OpTy)
176 && (Ty == Type::LongTy || Ty == Type::ULongTy
177 || Ty == Type::IntTy || Ty == Type::UIntTy))
178 || (isa<PointerType>(Ty)
179 && (OpTy == Type::LongTy || OpTy == Type::ULongTy
180 || OpTy == Type::IntTy || OpTy == Type::UIntTy))
181 || (((TD.getTypeSize(Ty) >= TD.getTypeSize(OpTy))
182 && OpTy->isLosslesslyConvertibleTo(Ty))))
183 && "FIXME: Don't yet support this kind of constant cast expr");
185 emitConstantValueOnly(Op);
189 case Instruction::Add:
191 emitConstantValueOnly(CE->getOperand(0));
193 emitConstantValueOnly(CE->getOperand(1));
197 assert(0 && "Unsupported operator!");
200 assert(0 && "Unknown constant value!");
204 // Print a constant value or values, with the appropriate storage class as a
206 void V8Printer::emitGlobalConstant(const Constant *CV) {
207 const TargetData &TD = TM.getTargetData();
209 if (CV->isNullValue()) {
210 O << "\t.zero\t " << TD.getTypeSize(CV->getType()) << "\n";
212 } else if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
213 if (CVA->isString()) {
215 printAsCString(O, CVA);
217 } else { // Not a string. Print the values in successive locations
218 const std::vector<Use> &constValues = CVA->getValues();
219 for (unsigned i=0; i < constValues.size(); i++)
220 emitGlobalConstant(cast<Constant>(constValues[i].get()));
223 } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
224 // Print the fields in successive locations. Pad to align if needed!
225 const StructLayout *cvsLayout = TD.getStructLayout(CVS->getType());
226 const std::vector<Use>& constValues = CVS->getValues();
227 unsigned sizeSoFar = 0;
228 for (unsigned i=0, N = constValues.size(); i < N; i++) {
229 const Constant* field = cast<Constant>(constValues[i].get());
231 // Check if padding is needed and insert one or more 0s.
232 unsigned fieldSize = TD.getTypeSize(field->getType());
233 unsigned padSize = ((i == N-1? cvsLayout->StructSize
234 : cvsLayout->MemberOffsets[i+1])
235 - cvsLayout->MemberOffsets[i]) - fieldSize;
236 sizeSoFar += fieldSize + padSize;
238 // Now print the actual field value
239 emitGlobalConstant(field);
241 // Insert the field padding unless it's zero bytes...
243 O << "\t.zero\t " << padSize << "\n";
245 assert(sizeSoFar == cvsLayout->StructSize &&
246 "Layout of constant struct may be incorrect!");
248 } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
249 // FP Constants are printed as integer constants to avoid losing
251 double Val = CFP->getValue();
252 switch (CFP->getType()->getTypeID()) {
253 default: assert(0 && "Unknown floating point type!");
254 case Type::FloatTyID: {
255 union FU { // Abide by C TBAA rules
260 O << ".long\t" << U.UVal << "\t! float " << Val << "\n";
263 case Type::DoubleTyID: {
264 union DU { // Abide by C TBAA rules
269 O << ".quad\t" << U.UVal << "\t! double " << Val << "\n";
275 const Type *type = CV->getType();
277 switch (type->getTypeID()) {
278 case Type::BoolTyID: case Type::UByteTyID: case Type::SByteTyID:
281 case Type::UShortTyID: case Type::ShortTyID:
284 case Type::FloatTyID: case Type::PointerTyID:
285 case Type::UIntTyID: case Type::IntTyID:
288 case Type::DoubleTyID:
289 case Type::ULongTyID: case Type::LongTyID:
293 assert (0 && "Can't handle printing this type of thing");
297 emitConstantValueOnly(CV);
301 /// printConstantPool - Print to the current output stream assembly
302 /// representations of the constants in the constant pool MCP. This is
303 /// used to print out constants which have been "spilled to memory" by
304 /// the code generator.
306 void V8Printer::printConstantPool(MachineConstantPool *MCP) {
307 const std::vector<Constant*> &CP = MCP->getConstants();
308 const TargetData &TD = TM.getTargetData();
310 if (CP.empty()) return;
312 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
313 O << "\t.section .rodata\n";
314 O << "\t.align " << (unsigned)TD.getTypeAlignment(CP[i]->getType())
316 O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t!"
318 emitGlobalConstant(CP[i]);
322 /// runOnMachineFunction - This uses the printMachineInstruction()
323 /// method to print assembly for each instruction.
325 bool V8Printer::runOnMachineFunction(MachineFunction &MF) {
326 // BBNumber is used here so that a given Printer will never give two
327 // BBs the same name. (If you have a better way, please let me know!)
328 static unsigned BBNumber = 0;
331 // What's my mangled name?
332 CurrentFnName = Mang->getValueName(MF.getFunction());
334 // Print out constants referenced by the function
335 printConstantPool(MF.getConstantPool());
337 // Print out labels for the function.
339 O << "\t.align 16\n";
340 O << "\t.globl\t" << CurrentFnName << "\n";
341 O << "\t.type\t" << CurrentFnName << ", #function\n";
342 O << CurrentFnName << ":\n";
344 // Number each basic block so that we can consistently refer to them
345 // in PC-relative references.
347 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
349 NumberForBB[I->getBasicBlock()] = BBNumber++;
352 // Print out code for the function.
353 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
355 // Print a label for the basic block.
356 O << ".LBB" << Mang->getValueName(MF.getFunction ())
357 << "_" << I->getNumber () << ":\t! "
358 << I->getBasicBlock ()->getName () << "\n";
359 for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
361 // Print the assembly for the instruction.
363 printMachineInstruction(II);
367 // We didn't modify anything.
372 std::string LowercaseString (const std::string &S) {
373 std::string result (S);
374 for (unsigned i = 0; i < S.length(); ++i)
375 if (isupper (result[i]))
376 result[i] = tolower(result[i]);
380 void V8Printer::printOperand(const MachineInstr *MI, int opNum) {
381 const MachineOperand &MO = MI->getOperand (opNum);
382 const MRegisterInfo &RI = *TM.getRegisterInfo();
383 bool CloseParen = false;
384 if (MI->getOpcode() == V8::SETHIi && !MO.isRegister() && !MO.isImmediate()) {
387 } else if (MI->getOpcode() ==V8::ORri &&!MO.isRegister() &&!MO.isImmediate()) {
391 switch (MO.getType()) {
392 case MachineOperand::MO_VirtualRegister:
393 if (Value *V = MO.getVRegValueOrNull()) {
394 O << "<" << V->getName() << ">";
398 case MachineOperand::MO_MachineRegister:
399 if (MRegisterInfo::isPhysicalRegister(MO.getReg()))
400 O << "%" << LowercaseString (RI.get(MO.getReg()).Name);
402 O << "%reg" << MO.getReg();
405 case MachineOperand::MO_SignExtendedImmed:
406 case MachineOperand::MO_UnextendedImmed:
407 O << (int)MO.getImmedValue();
409 case MachineOperand::MO_MachineBasicBlock: {
410 MachineBasicBlock *MBBOp = MO.getMachineBasicBlock();
411 O << ".LBB" << Mang->getValueName(MBBOp->getParent()->getFunction())
412 << "_" << MBBOp->getNumber () << "\t! "
413 << MBBOp->getBasicBlock ()->getName ();
416 case MachineOperand::MO_PCRelativeDisp:
417 std::cerr << "Shouldn't use addPCDisp() when building SparcV8 MachineInstrs";
420 case MachineOperand::MO_GlobalAddress:
421 O << Mang->getValueName(MO.getGlobal());
423 case MachineOperand::MO_ExternalSymbol:
424 O << MO.getSymbolName();
427 O << "<unknown operand type>"; break;
429 if (CloseParen) O << ")";
432 static bool isLoadInstruction (const MachineInstr *MI) {
433 switch (MI->getOpcode ()) {
446 static bool isStoreInstruction (const MachineInstr *MI) {
447 switch (MI->getOpcode ()) {
458 void V8Printer::printBaseOffsetPair (const MachineInstr *MI, int i) {
460 printOperand (MI, i);
461 assert (MI->getOperand (i + 1).isImmediate()
462 && "2nd half of base-offset pair must be immediate-value machine operand");
463 int Val = (int) MI->getOperand (i + 1).getImmedValue ();
465 O << ((Val >= 0) ? " + " : " - ");
466 O << ((Val >= 0) ? Val : -Val);
471 /// printMachineInstruction -- Print out a single SparcV8 LLVM instruction
472 /// MI in GAS syntax to the current output stream.
474 void V8Printer::printMachineInstruction(const MachineInstr *MI) {
475 unsigned Opcode = MI->getOpcode();
476 const TargetInstrInfo &TII = *TM.getInstrInfo();
477 const TargetInstrDescriptor &Desc = TII.get(Opcode);
478 O << Desc.Name << " ";
480 // Printing memory instructions is a special case.
481 // for loads: %dest = op %base, offset --> op [%base + offset], %dest
482 // for stores: op %src, %base, offset --> op %src, [%base + offset]
483 if (isLoadInstruction (MI)) {
484 printBaseOffsetPair (MI, 1);
486 printOperand (MI, 0);
489 } else if (isStoreInstruction (MI)) {
490 printOperand (MI, 0);
492 printBaseOffsetPair (MI, 1);
497 // print non-immediate, non-register-def operands
498 // then print immediate operands
499 // then print register-def operands.
500 std::vector<int> print_order;
501 for (unsigned i = 0; i < MI->getNumOperands (); ++i)
502 if (!(MI->getOperand (i).isImmediate ()
503 || (MI->getOperand (i).isRegister ()
504 && MI->getOperand (i).isDef ())))
505 print_order.push_back (i);
506 for (unsigned i = 0; i < MI->getNumOperands (); ++i)
507 if (MI->getOperand (i).isImmediate ())
508 print_order.push_back (i);
509 for (unsigned i = 0; i < MI->getNumOperands (); ++i)
510 if (MI->getOperand (i).isRegister () && MI->getOperand (i).isDef ())
511 print_order.push_back (i);
512 for (unsigned i = 0, e = print_order.size (); i != e; ++i) {
513 printOperand (MI, print_order[i]);
514 if (i != (print_order.size () - 1))
520 bool V8Printer::doInitialization(Module &M) {
521 Mang = new Mangler(M);
522 return false; // success
525 // SwitchSection - Switch to the specified section of the executable if we are
526 // not already in it!
528 static void SwitchSection(std::ostream &OS, std::string &CurSection,
529 const char *NewSection) {
530 if (CurSection != NewSection) {
531 CurSection = NewSection;
532 if (!CurSection.empty())
533 OS << "\t" << NewSection << "\n";
537 bool V8Printer::doFinalization(Module &M) {
538 const TargetData &TD = TM.getTargetData();
539 std::string CurSection;
541 // Print out module-level global variables here.
542 for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
543 if (I->hasInitializer()) { // External global require no code
545 std::string name = Mang->getValueName(I);
546 Constant *C = I->getInitializer();
547 unsigned Size = TD.getTypeSize(C->getType());
548 unsigned Align = TD.getTypeAlignment(C->getType());
550 if (C->isNullValue() &&
551 (I->hasLinkOnceLinkage() || I->hasInternalLinkage() ||
552 I->hasWeakLinkage() /* FIXME: Verify correct */)) {
553 SwitchSection(O, CurSection, ".data");
554 if (I->hasInternalLinkage())
555 O << "\t.local " << name << "\n";
557 O << "\t.comm " << name << "," << TD.getTypeSize(C->getType())
558 << "," << (unsigned)TD.getTypeAlignment(C->getType());
560 WriteAsOperand(O, I, true, true, &M);
563 switch (I->getLinkage()) {
564 case GlobalValue::LinkOnceLinkage:
565 case GlobalValue::WeakLinkage: // FIXME: Verify correct for weak.
566 // Nonnull linkonce -> weak
567 O << "\t.weak " << name << "\n";
568 SwitchSection(O, CurSection, "");
569 O << "\t.section\t.llvm.linkonce.d." << name << ",\"aw\",@progbits\n";
572 case GlobalValue::AppendingLinkage:
573 // FIXME: appending linkage variables should go into a section of
574 // their name or something. For now, just emit them as external.
575 case GlobalValue::ExternalLinkage:
576 // If external or appending, declare as a global symbol
577 O << "\t.globl " << name << "\n";
579 case GlobalValue::InternalLinkage:
580 if (C->isNullValue())
581 SwitchSection(O, CurSection, ".bss");
583 SwitchSection(O, CurSection, ".data");
587 O << "\t.align " << Align << "\n";
588 O << "\t.type " << name << ",#object\n";
589 O << "\t.size " << name << "," << Size << "\n";
590 O << name << ":\t\t\t\t! ";
591 WriteAsOperand(O, I, true, true, &M);
593 WriteAsOperand(O, C, false, false, &M);
595 emitGlobalConstant(C);
600 return false; // success