1 //===-- PPC32/Printer.cpp - Convert X86 LLVM code to Intel assembly ---------===//
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
11 // representation of machine-dependent LLVM code to Intel-format
12 // assembly language. This printer is the output mechanism used
13 // by `llc' and `lli -print-machineinstrs' on X86.
15 //===----------------------------------------------------------------------===//
17 #define DEBUG_TYPE "asmprinter"
19 #include "PowerPCInstrInfo.h"
20 #include "llvm/Constants.h"
21 #include "llvm/DerivedTypes.h"
22 #include "llvm/Module.h"
23 #include "llvm/Assembly/Writer.h"
24 #include "llvm/CodeGen/MachineConstantPool.h"
25 #include "llvm/CodeGen/MachineFunctionPass.h"
26 #include "llvm/CodeGen/MachineInstr.h"
27 #include "llvm/Target/TargetMachine.h"
28 #include "llvm/Support/Mangler.h"
29 #include "Support/CommandLine.h"
30 #include "Support/Debug.h"
31 #include "Support/Statistic.h"
32 #include "Support/StringExtras.h"
38 Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");
40 struct Printer : public MachineFunctionPass {
41 /// Output stream on which we're printing assembly code.
45 /// Target machine description which we query for reg. names, data
50 /// Name-mangler for global names.
53 std::set< std::string > Stubs;
54 std::set<std::string> Strings;
56 Printer(std::ostream &o, TargetMachine &tm) : O(o), TM(tm) { }
58 /// We name each basic block in a Function with a unique number, so
59 /// that we can consistently refer to them later. This is cleared
60 /// at the beginning of each call to runOnMachineFunction().
62 typedef std::map<const Value *, unsigned> ValueMapTy;
63 ValueMapTy NumberForBB;
65 /// Cache of mangled name for current function. This is
66 /// recalculated at the beginning of each call to
67 /// runOnMachineFunction().
69 std::string CurrentFnName;
71 virtual const char *getPassName() const {
72 return "PowerPC Assembly Printer";
75 void printMachineInstruction(const MachineInstr *MI);
76 void printOp(const MachineOperand &MO,
77 bool elideOffsetKeyword = false);
78 void printConstantPool(MachineConstantPool *MCP);
79 bool runOnMachineFunction(MachineFunction &F);
80 bool doInitialization(Module &M);
81 bool doFinalization(Module &M);
82 void emitGlobalConstant(const Constant* CV);
83 void emitConstantValueOnly(const Constant *CV);
85 } // end of anonymous namespace
87 /// createPPCCodePrinterPass - Returns a pass that prints the X86
88 /// assembly code for a MachineFunction to the given output stream,
89 /// using the given target machine description. This should work
90 /// regardless of whether the function is in SSA form.
92 FunctionPass *createPPCCodePrinterPass(std::ostream &o,TargetMachine &tm){
93 return new Printer(o, tm);
96 /// isStringCompatible - Can we treat the specified array as a string?
97 /// Only if it is an array of ubytes or non-negative sbytes.
99 static bool isStringCompatible(const ConstantArray *CVA) {
100 const Type *ETy = cast<ArrayType>(CVA->getType())->getElementType();
101 if (ETy == Type::UByteTy) return true;
102 if (ETy != Type::SByteTy) return false;
104 for (unsigned i = 0; i < CVA->getNumOperands(); ++i)
105 if (cast<ConstantSInt>(CVA->getOperand(i))->getValue() < 0)
111 /// toOctal - Convert the low order bits of X into an octal digit.
113 static inline char toOctal(int X) {
117 /// getAsCString - Return the specified array as a C compatible
118 /// string, only if the predicate isStringCompatible is true.
120 static void printAsCString(std::ostream &O, const ConstantArray *CVA) {
121 assert(isStringCompatible(CVA) && "Array is not string compatible!");
124 for (unsigned i = 0; i < CVA->getNumOperands(); ++i) {
125 unsigned char C = cast<ConstantInt>(CVA->getOperand(i))->getRawValue();
129 } else if (C == '\\') {
131 } else if (isprint(C)) {
135 case '\b': O << "\\b"; break;
136 case '\f': O << "\\f"; break;
137 case '\n': O << "\\n"; break;
138 case '\r': O << "\\r"; break;
139 case '\t': O << "\\t"; break;
142 O << toOctal(C >> 6);
143 O << toOctal(C >> 3);
144 O << toOctal(C >> 0);
152 // Print out the specified constant, without a storage class. Only the
153 // constants valid in constant expressions can occur here.
154 void Printer::emitConstantValueOnly(const Constant *CV) {
155 if (CV->isNullValue())
157 else if (const ConstantBool *CB = dyn_cast<ConstantBool>(CV)) {
158 assert(CB == ConstantBool::True);
160 } else if (const ConstantSInt *CI = dyn_cast<ConstantSInt>(CV))
162 else if (const ConstantUInt *CI = dyn_cast<ConstantUInt>(CV))
164 else if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(CV))
165 // This is a constant address for a global variable or function. Use the
166 // name of the variable or function as the address value.
167 O << Mang->getValueName(CPR->getValue());
168 else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
169 const TargetData &TD = TM.getTargetData();
170 switch(CE->getOpcode()) {
171 case Instruction::GetElementPtr: {
172 // generate a symbolic expression for the byte address
173 const Constant *ptrVal = CE->getOperand(0);
174 std::vector<Value*> idxVec(CE->op_begin()+1, CE->op_end());
175 if (unsigned Offset = TD.getIndexedOffset(ptrVal->getType(), idxVec)) {
177 emitConstantValueOnly(ptrVal);
178 O << ") + " << Offset;
180 emitConstantValueOnly(ptrVal);
184 case Instruction::Cast: {
185 // Support only non-converting or widening casts for now, that is, ones
186 // that do not involve a change in value. This assertion is really gross,
187 // and may not even be a complete check.
188 Constant *Op = CE->getOperand(0);
189 const Type *OpTy = Op->getType(), *Ty = CE->getType();
191 // Remember, kids, pointers on x86 can be losslessly converted back and
192 // forth into 32-bit or wider integers, regardless of signedness. :-P
193 assert(((isa<PointerType>(OpTy)
194 && (Ty == Type::LongTy || Ty == Type::ULongTy
195 || Ty == Type::IntTy || Ty == Type::UIntTy))
196 || (isa<PointerType>(Ty)
197 && (OpTy == Type::LongTy || OpTy == Type::ULongTy
198 || OpTy == Type::IntTy || OpTy == Type::UIntTy))
199 || (((TD.getTypeSize(Ty) >= TD.getTypeSize(OpTy))
200 && OpTy->isLosslesslyConvertibleTo(Ty))))
201 && "FIXME: Don't yet support this kind of constant cast expr");
203 emitConstantValueOnly(Op);
207 case Instruction::Add:
209 emitConstantValueOnly(CE->getOperand(0));
211 emitConstantValueOnly(CE->getOperand(1));
215 assert(0 && "Unsupported operator!");
218 assert(0 && "Unknown constant value!");
222 // Print a constant value or values, with the appropriate storage class as a
224 void Printer::emitGlobalConstant(const Constant *CV) {
225 const TargetData &TD = TM.getTargetData();
227 if (CV->isNullValue()) {
228 O << "\t.space\t " << TD.getTypeSize(CV->getType()) << "\n";
230 } else if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
231 if (isStringCompatible(CVA)) {
233 printAsCString(O, CVA);
235 } else { // Not a string. Print the values in successive locations
236 const std::vector<Use> &constValues = CVA->getValues();
237 for (unsigned i=0; i < constValues.size(); i++)
238 emitGlobalConstant(cast<Constant>(constValues[i].get()));
241 } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
242 // Print the fields in successive locations. Pad to align if needed!
243 const StructLayout *cvsLayout = TD.getStructLayout(CVS->getType());
244 const std::vector<Use>& constValues = CVS->getValues();
245 unsigned sizeSoFar = 0;
246 for (unsigned i=0, N = constValues.size(); i < N; i++) {
247 const Constant* field = cast<Constant>(constValues[i].get());
249 // Check if padding is needed and insert one or more 0s.
250 unsigned fieldSize = TD.getTypeSize(field->getType());
251 unsigned padSize = ((i == N-1? cvsLayout->StructSize
252 : cvsLayout->MemberOffsets[i+1])
253 - cvsLayout->MemberOffsets[i]) - fieldSize;
254 sizeSoFar += fieldSize + padSize;
256 // Now print the actual field value
257 emitGlobalConstant(field);
259 // Insert the field padding unless it's zero bytes...
261 O << "\t.space\t " << padSize << "\n";
263 assert(sizeSoFar == cvsLayout->StructSize &&
264 "Layout of constant struct may be incorrect!");
266 } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
267 // FP Constants are printed as integer constants to avoid losing
269 double Val = CFP->getValue();
270 switch (CFP->getType()->getTypeID()) {
271 default: assert(0 && "Unknown floating point type!");
272 case Type::FloatTyID: {
273 union FU { // Abide by C TBAA rules
278 O << ".long\t" << U.UVal << "\t# float " << Val << "\n";
281 case Type::DoubleTyID: {
282 union DU { // Abide by C TBAA rules
292 O << ".long\t" << U.T.MSWord << "\t# double most significant word " << Val << "\n";
293 O << ".long\t" << U.T.LSWord << "\t# double least significant word" << Val << "\n";
297 } else if (CV->getType()->getPrimitiveSize() == 64) {
298 const ConstantInt *CI = dyn_cast<ConstantInt>(CV);
300 union DU { // Abide by C TBAA rules
307 U.UVal = CI->getRawValue();
309 O << ".long\t" << U.T.MSWord << "\t# Double-word most significant word " << U.UVal << "\n";
310 O << ".long\t" << U.T.LSWord << "\t# Double-word least significant word" << U.UVal << "\n";
315 const Type *type = CV->getType();
317 switch (type->getTypeID()) {
318 case Type::UByteTyID: case Type::SByteTyID:
321 case Type::UShortTyID: case Type::ShortTyID:
325 case Type::PointerTyID:
326 case Type::UIntTyID: case Type::IntTyID:
329 case Type::ULongTyID: case Type::LongTyID:
330 assert (0 && "Should have already output double-word constant.");
331 case Type::FloatTyID: case Type::DoubleTyID:
332 assert (0 && "Should have already output floating point constant.");
334 assert (0 && "Can't handle printing this type of thing");
338 emitConstantValueOnly(CV);
342 /// printConstantPool - Print to the current output stream assembly
343 /// representations of the constants in the constant pool MCP. This is
344 /// used to print out constants which have been "spilled to memory" by
345 /// the code generator.
347 void Printer::printConstantPool(MachineConstantPool *MCP) {
348 const std::vector<Constant*> &CP = MCP->getConstants();
349 const TargetData &TD = TM.getTargetData();
351 if (CP.empty()) return;
353 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
355 O << "\t.align " << (unsigned)TD.getTypeAlignment(CP[i]->getType())
357 O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t#"
359 emitGlobalConstant(CP[i]);
363 /// runOnMachineFunction - This uses the printMachineInstruction()
364 /// method to print assembly for each instruction.
366 bool Printer::runOnMachineFunction(MachineFunction &MF) {
367 // BBNumber is used here so that a given Printer will never give two
368 // BBs the same name. (If you have a better way, please let me know!)
369 static unsigned BBNumber = 0;
372 // What's my mangled name?
373 CurrentFnName = Mang->getValueName(MF.getFunction());
375 // Print out constants referenced by the function
376 printConstantPool(MF.getConstantPool());
378 // Print out labels for the function.
380 O << "\t.globl\t" << CurrentFnName << "\n";
382 O << CurrentFnName << ":\n";
384 // Number each basic block so that we can consistently refer to them
385 // in PC-relative references.
387 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
389 NumberForBB[I->getBasicBlock()] = BBNumber++;
392 // Print out code for the function.
393 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
395 // Print a label for the basic block.
396 O << "L" << NumberForBB[I->getBasicBlock()] << ":\t# "
397 << I->getBasicBlock()->getName() << "\n";
398 for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
400 // Print the assembly for the instruction.
402 printMachineInstruction(II);
406 // We didn't modify anything.
412 void Printer::printOp(const MachineOperand &MO,
413 bool elideOffsetKeyword /* = false */) {
414 const MRegisterInfo &RI = *TM.getRegisterInfo();
417 switch (MO.getType()) {
418 case MachineOperand::MO_VirtualRegister:
419 if (Value *V = MO.getVRegValueOrNull()) {
420 O << "<" << V->getName() << ">";
424 case MachineOperand::MO_MachineRegister:
425 O << RI.get(MO.getReg()).Name;
428 case MachineOperand::MO_SignExtendedImmed:
429 case MachineOperand::MO_UnextendedImmed:
430 O << (int)MO.getImmedValue();
432 case MachineOperand::MO_MachineBasicBlock: {
433 MachineBasicBlock *MBBOp = MO.getMachineBasicBlock();
434 O << ".LBB" << Mang->getValueName(MBBOp->getParent()->getFunction())
435 << "_" << MBBOp->getNumber () << "\t# "
436 << MBBOp->getBasicBlock ()->getName ();
439 case MachineOperand::MO_PCRelativeDisp:
440 std::cerr << "Shouldn't use addPCDisp() when building PPC MachineInstrs";
443 case MachineOperand::MO_GlobalAddress:
444 if (!elideOffsetKeyword) {
445 if(isa<Function>(MO.getGlobal())) {
446 Stubs.insert(Mang->getValueName(MO.getGlobal()));
447 O << "L" << Mang->getValueName(MO.getGlobal()) << "$stub";
449 O << Mang->getValueName(MO.getGlobal());
453 case MachineOperand::MO_ExternalSymbol:
454 O << MO.getSymbolName();
457 O << "<unknown operand type>"; return;
463 unsigned int ValidOpcodes(const MachineInstr *MI, unsigned int ArgType[5]) {
465 unsigned int retval = 1;
467 for(i = 0; i<5; i++) {
498 /// printMachineInstruction -- Print out a single PPC32 LLVM instruction
499 /// MI in Darwin syntax to the current output stream.
501 void Printer::printMachineInstruction(const MachineInstr *MI) {
502 unsigned Opcode = MI->getOpcode();
503 const TargetInstrInfo &TII = *TM.getInstrInfo();
504 const TargetInstrDescriptor &Desc = TII.get(Opcode);
507 unsigned int ArgCount = Desc.TSFlags & PPC32II::ArgCountMask;
508 unsigned int ArgType[5];
511 ArgType[0] = (Desc.TSFlags>>PPC32II::Arg0TypeShift) & PPC32II::ArgTypeMask;
512 ArgType[1] = (Desc.TSFlags>>PPC32II::Arg1TypeShift) & PPC32II::ArgTypeMask;
513 ArgType[2] = (Desc.TSFlags>>PPC32II::Arg2TypeShift) & PPC32II::ArgTypeMask;
514 ArgType[3] = (Desc.TSFlags>>PPC32II::Arg3TypeShift) & PPC32II::ArgTypeMask;
515 ArgType[4] = (Desc.TSFlags>>PPC32II::Arg4TypeShift) & PPC32II::ArgTypeMask;
517 assert ( ((Desc.TSFlags & PPC32II::VMX) == 0) && "Instruction requires VMX support");
518 assert ( ((Desc.TSFlags & PPC32II::PPC64) == 0) && "Instruction requires 64 bit support");
519 //assert ( ValidOpcodes(MI, ArgType) && "Instruction has invalid inputs");
522 if(Opcode == PPC32::MovePCtoLR) {
524 O << "bcl 20,31,L" << CurrentFnName << "$pb\n";
525 O << "L" << CurrentFnName << "$pb:\n";
529 O << TII.getName(MI->getOpcode()) << " ";
530 DEBUG(std::cerr << TII.getName(MI->getOpcode()) << " expects "
531 << ArgCount << " args\n");
533 if(Opcode == PPC32::LOADLoAddr) {
534 printOp(MI->getOperand(0));
536 printOp(MI->getOperand(1));
538 printOp(MI->getOperand(2));
539 O << "-L" << CurrentFnName << "$pb)\n";
543 if(Opcode == PPC32::LOADHiAddr) {
544 printOp(MI->getOperand(0));
546 printOp(MI->getOperand(1));
548 printOp(MI->getOperand(2));
549 O << "-L" << CurrentFnName << "$pb)\n";
553 if( (ArgCount == 3) && (ArgType[1] == PPC32II::Disimm16) ) {
554 printOp(MI->getOperand(0));
556 printOp(MI->getOperand(1));
558 if((ArgType[2] == PPC32II::Gpr0) && (MI->getOperand(2).getReg() == PPC32::R0)) {
561 printOp(MI->getOperand(2));
565 for(i = 0; i< ArgCount; i++) {
566 if( (ArgType[i] == PPC32II::Gpr0) && ((MI->getOperand(i).getReg()) == PPC32::R0)) {
569 //std::cout << "DEBUG " << (*(TM.getRegisterInfo())).get(MI->getOperand(i).getReg()).Name << "\n";
570 printOp(MI->getOperand(i));
572 if( ArgCount - 1 == i) {
583 bool Printer::doInitialization(Module &M) {
584 // Tell gas we are outputting Intel syntax (not AT&T syntax) assembly.
586 // Bug: gas in `intel_syntax noprefix' mode interprets the symbol `Sp' in an
587 // instruction as a reference to the register named sp, and if you try to
588 // reference a symbol `Sp' (e.g. `mov ECX, OFFSET Sp') then it gets lowercased
589 // before being looked up in the symbol table. This creates spurious
590 // `undefined symbol' errors when linking. Workaround: Do not use `noprefix'
591 // mode, and decorate all register names with percent signs.
592 // O << "\t.intel_syntax\n";
593 Mang = new Mangler(M, true);
594 return false; // success
597 // SwitchSection - Switch to the specified section of the executable if we are
598 // not already in it!
600 static void SwitchSection(std::ostream &OS, std::string &CurSection,
601 const char *NewSection) {
602 if (CurSection != NewSection) {
603 CurSection = NewSection;
604 if (!CurSection.empty())
605 OS << "\t" << NewSection << "\n";
609 bool Printer::doFinalization(Module &M) {
610 const TargetData &TD = TM.getTargetData();
611 std::string CurSection;
613 // Print out module-level global variables here.
614 for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
615 if (I->hasInitializer()) { // External global require no code
617 std::string name = Mang->getValueName(I);
618 Constant *C = I->getInitializer();
619 unsigned Size = TD.getTypeSize(C->getType());
620 unsigned Align = TD.getTypeAlignment(C->getType());
622 if (C->isNullValue() &&
623 (I->hasLinkOnceLinkage() || I->hasInternalLinkage() ||
624 I->hasWeakLinkage() /* FIXME: Verify correct */)) {
625 SwitchSection(O, CurSection, ".data");
626 if (I->hasInternalLinkage())
627 O << "\t.local " << name << "\n";
629 O << "\t.comm " << name << "," << TD.getTypeSize(C->getType())
630 << "," << (unsigned)TD.getTypeAlignment(C->getType());
632 WriteAsOperand(O, I, true, true, &M);
635 switch (I->getLinkage()) {
636 case GlobalValue::LinkOnceLinkage:
637 case GlobalValue::WeakLinkage: // FIXME: Verify correct for weak.
638 // Nonnull linkonce -> weak
639 O << "\t.weak " << name << "\n";
640 SwitchSection(O, CurSection, "");
641 O << "\t.section\t.llvm.linkonce.d." << name << ",\"aw\",@progbits\n";
644 case GlobalValue::AppendingLinkage:
645 // FIXME: appending linkage variables should go into a section of
646 // their name or something. For now, just emit them as external.
647 case GlobalValue::ExternalLinkage:
648 // If external or appending, declare as a global symbol
649 O << "\t.globl " << name << "\n";
651 case GlobalValue::InternalLinkage:
652 if (C->isNullValue())
653 SwitchSection(O, CurSection, ".bss");
655 SwitchSection(O, CurSection, ".data");
659 O << "\t.align " << Align << "\n";
660 O << name << ":\t\t\t\t# ";
661 WriteAsOperand(O, I, true, true, &M);
663 WriteAsOperand(O, C, false, false, &M);
665 emitGlobalConstant(C);
669 for(std::set<std::string>::iterator i = Stubs.begin(); i != Stubs.end(); ++i) {
671 O << ".section __TEXT,__picsymbolstub1,symbol_stubs,pure_instructions,32\n";
673 O << "L" << *i << "$stub:\n";
674 O << "\t.indirect_symbol " << *i << "\n";
676 O << "\tbcl 20,31,L0$" << *i << "\n";
677 O << "L0$" << *i << ":\n";
679 O << "\taddis r11,r11,ha16(L" << *i << "$lazy_ptr-L0$" << *i << ")\n";
681 O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
682 O << "\tmtctr r12\n";
685 O << ".lazy_symbol_pointer\n";
686 O << "L" << *i << "$lazy_ptr:\n";
687 O << ".indirect_symbol " << *i << "\n";
688 O << ".long dyld_stub_binding_helper\n";
693 return false; // success
696 } // End llvm namespace