1 //===-- PowerPCAsmPrinter.cpp - Print machine instrs to PowerPC 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 representation
11 // of machine-dependent LLVM code to PowerPC assembly language. This printer is
12 // the output mechanism used by `llc'.
14 // Documentation at http://developer.apple.com/documentation/DeveloperTools/
15 // Reference/Assembler/ASMIntroduction/chapter_1_section_1.html
17 //===----------------------------------------------------------------------===//
19 #define DEBUG_TYPE "asmprinter"
21 #include "PowerPCTargetMachine.h"
22 #include "llvm/Constants.h"
23 #include "llvm/DerivedTypes.h"
24 #include "llvm/Module.h"
25 #include "llvm/Assembly/Writer.h"
26 #include "llvm/CodeGen/AsmPrinter.h"
27 #include "llvm/CodeGen/MachineConstantPool.h"
28 #include "llvm/CodeGen/MachineFunctionPass.h"
29 #include "llvm/CodeGen/MachineInstr.h"
30 #include "llvm/CodeGen/ValueTypes.h"
31 #include "llvm/Support/Mangler.h"
32 #include "llvm/Support/MathExtras.h"
33 #include "llvm/Support/CommandLine.h"
34 #include "llvm/Support/Debug.h"
35 #include "llvm/Target/MRegisterInfo.h"
36 #include "llvm/Target/TargetInstrInfo.h"
37 #include "llvm/ADT/Statistic.h"
38 #include "llvm/ADT/StringExtras.h"
43 Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");
45 struct PowerPCAsmPrinter : public AsmPrinter {
46 std::set<std::string> FnStubs, GVStubs, LinkOnceStubs;
47 std::set<std::string> Strings;
49 PowerPCAsmPrinter(std::ostream &O, TargetMachine &TM)
50 : AsmPrinter(O, TM), LabelNumber(0) {}
52 /// Unique incrementer for label values for referencing Global values.
56 virtual const char *getPassName() const {
57 return "PowerPC Assembly Printer";
60 PowerPCTargetMachine &getTM() {
61 return static_cast<PowerPCTargetMachine&>(TM);
64 /// printInstruction - This method is automatically generated by tablegen
65 /// from the instruction set description. This method returns true if the
66 /// machine instruction was sufficiently described to print it, otherwise it
68 bool printInstruction(const MachineInstr *MI);
70 void printMachineInstruction(const MachineInstr *MI);
71 void printOp(const MachineOperand &MO, bool IsCallOp = false);
73 void printOperand(const MachineInstr *MI, unsigned OpNo, MVT::ValueType VT){
74 const MachineOperand &MO = MI->getOperand(OpNo);
75 if (MO.getType() == MachineOperand::MO_MachineRegister) {
76 assert(MRegisterInfo::isPhysicalRegister(MO.getReg())&&"Not physreg??");
77 O << LowercaseString(TM.getRegisterInfo()->get(MO.getReg()).Name);
78 } else if (MO.isImmediate()) {
79 O << MO.getImmedValue();
85 void printU5ImmOperand(const MachineInstr *MI, unsigned OpNo,
87 unsigned char value = MI->getOperand(OpNo).getImmedValue();
88 assert(value <= 31 && "Invalid u5imm argument!");
89 O << (unsigned int)value;
91 void printU6ImmOperand(const MachineInstr *MI, unsigned OpNo,
93 unsigned char value = MI->getOperand(OpNo).getImmedValue();
94 assert(value <= 63 && "Invalid u6imm argument!");
95 O << (unsigned int)value;
97 void printS16ImmOperand(const MachineInstr *MI, unsigned OpNo,
99 O << (short)MI->getOperand(OpNo).getImmedValue();
101 void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo,
103 O << (unsigned short)MI->getOperand(OpNo).getImmedValue();
105 void printBranchOperand(const MachineInstr *MI, unsigned OpNo,
107 // Branches can take an immediate operand. This is used by the branch
108 // selection pass to print $+8, an eight byte displacement from the PC.
109 if (MI->getOperand(OpNo).isImmediate()) {
110 O << "$+" << MI->getOperand(OpNo).getImmedValue() << '\n';
112 printOp(MI->getOperand(OpNo),
113 TM.getInstrInfo()->isCall(MI->getOpcode()));
116 void printPICLabel(const MachineInstr *MI, unsigned OpNo,
118 // FIXME: should probably be converted to cout.width and cout.fill
119 O << "\"L0000" << LabelNumber << "$pb\"\n";
120 O << "\"L0000" << LabelNumber << "$pb\":";
122 void printSymbolHi(const MachineInstr *MI, unsigned OpNo,
125 printOp(MI->getOperand(OpNo));
126 O << "-\"L0000" << LabelNumber << "$pb\")";
128 void printSymbolLo(const MachineInstr *MI, unsigned OpNo,
130 // FIXME: Because LFS, LFD, and LWZ can be used either with a s16imm or
131 // a lo16 of a global or constant pool operand, we must handle both here.
132 // this isn't a great design, but it works for now.
133 if (MI->getOperand(OpNo).isImmediate()) {
134 O << (short)MI->getOperand(OpNo).getImmedValue();
137 printOp(MI->getOperand(OpNo));
138 O << "-\"L0000" << LabelNumber << "$pb\")";
142 virtual void printConstantPool(MachineConstantPool *MCP) = 0;
143 virtual bool runOnMachineFunction(MachineFunction &F) = 0;
144 virtual bool doFinalization(Module &M) = 0;
147 /// DarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac OS
150 struct DarwinAsmPrinter : public PowerPCAsmPrinter {
152 DarwinAsmPrinter(std::ostream &O, TargetMachine &TM)
153 : PowerPCAsmPrinter(O, TM) {
156 ZeroDirective = "\t.space\t"; // ".space N" emits N zeros.
157 Data64bitsDirective = 0; // we can't emit a 64-bit unit
158 AlignmentIsInBytes = false; // Alignment is by power of 2.
161 virtual const char *getPassName() const {
162 return "Darwin PPC Assembly Printer";
165 void printConstantPool(MachineConstantPool *MCP);
166 bool runOnMachineFunction(MachineFunction &F);
167 bool doFinalization(Module &M);
170 /// AIXAsmPrinter - PowerPC assembly printer, customized for AIX
172 struct AIXAsmPrinter : public PowerPCAsmPrinter {
173 /// Map for labels corresponding to global variables
175 std::map<const GlobalVariable*,std::string> GVToLabelMap;
177 AIXAsmPrinter(std::ostream &O, TargetMachine &TM)
178 : PowerPCAsmPrinter(O, TM) {
181 ZeroDirective = "\t.space\t"; // ".space N" emits N zeros.
182 Data64bitsDirective = 0; // we can't emit a 64-bit unit
183 AlignmentIsInBytes = false; // Alignment is by power of 2.
186 virtual const char *getPassName() const {
187 return "AIX PPC Assembly Printer";
190 void printConstantPool(MachineConstantPool *MCP);
191 bool runOnMachineFunction(MachineFunction &F);
192 bool doInitialization(Module &M);
193 bool doFinalization(Module &M);
195 } // end of anonymous namespace
197 // SwitchSection - Switch to the specified section of the executable if we are
198 // not already in it!
200 static void SwitchSection(std::ostream &OS, std::string &CurSection,
201 const char *NewSection) {
202 if (CurSection != NewSection) {
203 CurSection = NewSection;
204 if (!CurSection.empty())
205 OS << "\t" << NewSection << "\n";
209 /// isStringCompatible - Can we treat the specified array as a string?
210 /// Only if it is an array of ubytes or non-negative sbytes.
212 static bool isStringCompatible(const ConstantArray *CVA) {
213 const Type *ETy = cast<ArrayType>(CVA->getType())->getElementType();
214 if (ETy == Type::UByteTy) return true;
215 if (ETy != Type::SByteTy) return false;
217 for (unsigned i = 0; i < CVA->getNumOperands(); ++i)
218 if (cast<ConstantSInt>(CVA->getOperand(i))->getValue() < 0)
224 /// toOctal - Convert the low order bits of X into an octal digit.
226 static inline char toOctal(int X) {
230 // Possible states while outputting ASCII strings
239 /// SwitchStringSection - manage the changes required to output bytes as
240 /// characters in a string vs. numeric decimal values
242 static inline void SwitchStringSection(std::ostream &O, StringSection NewSect,
243 StringSection &Current) {
244 if (Current == None) {
245 if (NewSect == Alpha)
247 else if (NewSect == Numeric)
249 } else if (Current == Alpha) {
252 else if (NewSect == Numeric)
255 } else if (Current == Numeric) {
256 if (NewSect == Alpha)
259 else if (NewSect == Numeric)
266 /// getAsCString - Return the specified array as a C compatible
267 /// string, only if the predicate isStringCompatible is true.
269 static void printAsCString(std::ostream &O, const ConstantArray *CVA) {
270 assert(isStringCompatible(CVA) && "Array is not string compatible!");
272 if (CVA->getNumOperands() == 0)
275 StringSection Current = None;
276 for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i) {
277 unsigned char C = cast<ConstantInt>(CVA->getOperand(i))->getRawValue();
279 SwitchStringSection(O, Alpha, Current);
281 } else if (isprint(C)) {
282 SwitchStringSection(O, Alpha, Current);
285 SwitchStringSection(O, Numeric, Current);
286 O << utostr((unsigned)C);
289 SwitchStringSection(O, None, Current);
293 /// createDarwinAsmPrinterPass - Returns a pass that prints the PPC assembly
294 /// code for a MachineFunction to the given output stream, in a format that the
295 /// Darwin assembler can deal with.
297 FunctionPass *llvm::createDarwinAsmPrinter(std::ostream &o, TargetMachine &tm) {
298 return new DarwinAsmPrinter(o, tm);
301 /// createAIXAsmPrinterPass - Returns a pass that prints the PPC assembly code
302 /// for a MachineFunction to the given output stream, in a format that the
303 /// AIX 5L assembler can deal with.
305 FunctionPass *llvm::createAIXAsmPrinter(std::ostream &o, TargetMachine &tm) {
306 return new AIXAsmPrinter(o, tm);
309 // Include the auto-generated portion of the assembly writer
310 #include "PowerPCGenAsmWriter.inc"
312 void PowerPCAsmPrinter::printOp(const MachineOperand &MO, bool IsCallOp) {
313 const MRegisterInfo &RI = *TM.getRegisterInfo();
316 switch (MO.getType()) {
317 case MachineOperand::MO_VirtualRegister:
318 if (Value *V = MO.getVRegValueOrNull()) {
319 O << "<" << V->getName() << ">";
323 case MachineOperand::MO_MachineRegister:
324 case MachineOperand::MO_CCRegister:
325 O << LowercaseString(RI.get(MO.getReg()).Name);
328 case MachineOperand::MO_SignExtendedImmed:
329 case MachineOperand::MO_UnextendedImmed:
330 std::cerr << "printOp() does not handle immediate values\n";
334 case MachineOperand::MO_PCRelativeDisp:
335 std::cerr << "Shouldn't use addPCDisp() when building PPC MachineInstrs";
339 case MachineOperand::MO_MachineBasicBlock: {
340 MachineBasicBlock *MBBOp = MO.getMachineBasicBlock();
341 O << ".LBB" << Mang->getValueName(MBBOp->getParent()->getFunction())
342 << "_" << MBBOp->getNumber() << "\t; "
343 << MBBOp->getBasicBlock()->getName();
347 case MachineOperand::MO_ConstantPoolIndex:
348 O << ".CPI" << CurrentFnName << "_" << MO.getConstantPoolIndex();
351 case MachineOperand::MO_ExternalSymbol:
352 O << MO.getSymbolName();
355 case MachineOperand::MO_GlobalAddress: {
356 GlobalValue *GV = MO.getGlobal();
357 std::string Name = Mang->getValueName(GV);
359 // Dynamically-resolved functions need a stub for the function. Be
360 // wary however not to output $stub for external functions whose addresses
361 // are taken. Those should be emitted as $non_lazy_ptr below.
362 Function *F = dyn_cast<Function>(GV);
363 if (F && IsCallOp && F->isExternal()) {
364 FnStubs.insert(Name);
365 O << "L" << Name << "$stub";
369 // External or weakly linked global variables need non-lazily-resolved stubs
370 if ((GV->isExternal() || GV->hasWeakLinkage() || GV->hasLinkOnceLinkage())){
371 if (GV->hasLinkOnceLinkage())
372 LinkOnceStubs.insert(Name);
374 GVStubs.insert(Name);
375 O << "L" << Name << "$non_lazy_ptr";
379 O << Mang->getValueName(GV);
384 O << "<unknown operand type: " << MO.getType() << ">";
389 /// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to
390 /// the current output stream.
392 void PowerPCAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
394 if (printInstruction(MI))
395 return; // Printer was automatically generated
397 assert(0 && "Unhandled instruction in asm writer!");
402 /// runOnMachineFunction - This uses the printMachineInstruction()
403 /// method to print assembly for each instruction.
405 bool DarwinAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
406 setupMachineFunction(MF);
409 // Print out constants referenced by the function
410 printConstantPool(MF.getConstantPool());
412 // Print out labels for the function.
415 O << "\t.globl\t" << CurrentFnName << "\n";
416 O << CurrentFnName << ":\n";
418 // Print out code for the function.
419 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
421 // Print a label for the basic block.
422 O << ".LBB" << CurrentFnName << "_" << I->getNumber() << ":\t"
423 << CommentString << " " << I->getBasicBlock()->getName() << "\n";
424 for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
426 // Print the assembly for the instruction.
428 printMachineInstruction(II);
433 // We didn't modify anything.
437 /// printConstantPool - Print to the current output stream assembly
438 /// representations of the constants in the constant pool MCP. This is
439 /// used to print out constants which have been "spilled to memory" by
440 /// the code generator.
442 void DarwinAsmPrinter::printConstantPool(MachineConstantPool *MCP) {
443 const std::vector<Constant*> &CP = MCP->getConstants();
444 const TargetData &TD = TM.getTargetData();
446 if (CP.empty()) return;
448 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
450 emitAlignment(TD.getTypeAlignmentShift(CP[i]->getType()));
451 O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t" << CommentString
453 emitGlobalConstant(CP[i]);
457 bool DarwinAsmPrinter::doFinalization(Module &M) {
458 const TargetData &TD = TM.getTargetData();
459 std::string CurSection;
461 // Print out module-level global variables here.
462 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I)
463 if (I->hasInitializer()) { // External global require no code
465 std::string name = Mang->getValueName(I);
466 Constant *C = I->getInitializer();
467 unsigned Size = TD.getTypeSize(C->getType());
468 unsigned Align = TD.getTypeAlignmentShift(C->getType());
470 if (C->isNullValue() && /* FIXME: Verify correct */
471 (I->hasInternalLinkage() || I->hasWeakLinkage() ||
472 I->hasLinkOnceLinkage())) {
473 SwitchSection(O, CurSection, ".data");
474 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
475 if (I->hasInternalLinkage())
476 O << ".lcomm " << name << "," << Size << "," << Align;
478 O << ".comm " << name << "," << Size;
480 WriteAsOperand(O, I, true, true, &M);
483 switch (I->getLinkage()) {
484 case GlobalValue::LinkOnceLinkage:
485 O << ".section __TEXT,__textcoal_nt,coalesced,no_toc\n"
486 << ".weak_definition " << name << '\n'
487 << ".private_extern " << name << '\n'
488 << ".section __DATA,__datacoal_nt,coalesced,no_toc\n";
489 LinkOnceStubs.insert(name);
491 case GlobalValue::WeakLinkage: // FIXME: Verify correct for weak.
492 // Nonnull linkonce -> weak
493 O << "\t.weak " << name << "\n";
494 SwitchSection(O, CurSection, "");
495 O << "\t.section\t.llvm.linkonce.d." << name << ",\"aw\",@progbits\n";
497 case GlobalValue::AppendingLinkage:
498 // FIXME: appending linkage variables should go into a section of
499 // their name or something. For now, just emit them as external.
500 case GlobalValue::ExternalLinkage:
501 // If external or appending, declare as a global symbol
502 O << "\t.globl " << name << "\n";
504 case GlobalValue::InternalLinkage:
505 SwitchSection(O, CurSection, ".data");
507 case GlobalValue::GhostLinkage:
508 std::cerr << "Error: unmaterialized (GhostLinkage) function in asm!";
512 emitAlignment(Align);
513 O << name << ":\t\t\t\t; ";
514 WriteAsOperand(O, I, true, true, &M);
516 WriteAsOperand(O, C, false, false, &M);
518 emitGlobalConstant(C);
522 // Output stubs for dynamically-linked functions
523 for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
527 O << ".section __TEXT,__picsymbolstub1,symbol_stubs,pure_instructions,32\n";
529 O << "L" << *i << "$stub:\n";
530 O << "\t.indirect_symbol " << *i << "\n";
532 O << "\tbcl 20,31,L0$" << *i << "\n";
533 O << "L0$" << *i << ":\n";
535 O << "\taddis r11,r11,ha16(L" << *i << "$lazy_ptr-L0$" << *i << ")\n";
537 O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
538 O << "\tmtctr r12\n";
541 O << ".lazy_symbol_pointer\n";
542 O << "L" << *i << "$lazy_ptr:\n";
543 O << "\t.indirect_symbol " << *i << "\n";
544 O << "\t.long dyld_stub_binding_helper\n";
549 // Output stubs for external global variables
550 if (GVStubs.begin() != GVStubs.end())
551 O << ".data\n.non_lazy_symbol_pointer\n";
552 for (std::set<std::string>::iterator i = GVStubs.begin(), e = GVStubs.end();
554 O << "L" << *i << "$non_lazy_ptr:\n";
555 O << "\t.indirect_symbol " << *i << "\n";
559 // Output stubs for link-once variables
560 if (LinkOnceStubs.begin() != LinkOnceStubs.end())
561 O << ".data\n.align 2\n";
562 for (std::set<std::string>::iterator i = LinkOnceStubs.begin(),
563 e = LinkOnceStubs.end(); i != e; ++i) {
564 O << "L" << *i << "$non_lazy_ptr:\n"
565 << "\t.long\t" << *i << '\n';
568 AsmPrinter::doFinalization(M);
569 return false; // success
572 /// runOnMachineFunction - This uses the printMachineInstruction()
573 /// method to print assembly for each instruction.
575 bool AIXAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
576 CurrentFnName = MF.getFunction()->getName();
578 // Print out constants referenced by the function
579 printConstantPool(MF.getConstantPool());
581 // Print out header for the function.
582 O << "\t.csect .text[PR]\n"
584 << "\t.globl " << CurrentFnName << '\n'
585 << "\t.globl ." << CurrentFnName << '\n'
586 << "\t.csect " << CurrentFnName << "[DS],3\n"
587 << CurrentFnName << ":\n"
588 << "\t.llong ." << CurrentFnName << ", TOC[tc0], 0\n"
589 << "\t.csect .text[PR]\n"
590 << '.' << CurrentFnName << ":\n";
592 // Print out code for the function.
593 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
595 // Print a label for the basic block.
596 O << "LBB" << CurrentFnName << "_" << I->getNumber() << ":\t# "
597 << I->getBasicBlock()->getName() << "\n";
598 for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
600 // Print the assembly for the instruction.
602 printMachineInstruction(II);
607 O << "LT.." << CurrentFnName << ":\n"
609 << "\t.byte 0,0,32,65,128,0,0,0\n"
610 << "\t.long LT.." << CurrentFnName << "-." << CurrentFnName << '\n'
612 << "\t.byte \"" << CurrentFnName << "\"\n"
615 // We didn't modify anything.
619 /// printConstantPool - Print to the current output stream assembly
620 /// representations of the constants in the constant pool MCP. This is
621 /// used to print out constants which have been "spilled to memory" by
622 /// the code generator.
624 void AIXAsmPrinter::printConstantPool(MachineConstantPool *MCP) {
625 const std::vector<Constant*> &CP = MCP->getConstants();
626 const TargetData &TD = TM.getTargetData();
628 if (CP.empty()) return;
630 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
632 O << "\t.align " << (unsigned)TD.getTypeAlignment(CP[i]->getType())
634 O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t;"
636 emitGlobalConstant(CP[i]);
640 bool AIXAsmPrinter::doInitialization(Module &M) {
641 const TargetData &TD = TM.getTargetData();
642 std::string CurSection;
644 O << "\t.machine \"ppc64\"\n"
646 << "\t.csect .text[PR]\n";
648 // Print out module-level global variables
649 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) {
650 if (!I->hasInitializer())
653 std::string Name = I->getName();
654 Constant *C = I->getInitializer();
655 // N.B.: We are defaulting to writable strings
656 if (I->hasExternalLinkage()) {
657 O << "\t.globl " << Name << '\n'
658 << "\t.csect .data[RW],3\n";
660 O << "\t.csect _global.rw_c[RW],3\n";
663 emitGlobalConstant(C);
666 // Output labels for globals
667 if (M.global_begin() != M.global_end()) O << "\t.toc\n";
668 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) {
669 const GlobalVariable *GV = I;
670 // Do not output labels for unused variables
671 if (GV->isExternal() && GV->use_begin() == GV->use_end())
674 std::string Name = GV->getName();
675 std::string Label = "LC.." + utostr(LabelNumber++);
676 GVToLabelMap[GV] = Label;
678 << "\t.tc " << Name << "[TC]," << Name;
679 if (GV->isExternal()) O << "[RW]";
683 Mang = new Mangler(M, ".");
684 return false; // success
687 bool AIXAsmPrinter::doFinalization(Module &M) {
688 const TargetData &TD = TM.getTargetData();
689 // Print out module-level global variables
690 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) {
691 if (I->hasInitializer() || I->hasExternalLinkage())
694 std::string Name = I->getName();
695 if (I->hasInternalLinkage()) {
696 O << "\t.lcomm " << Name << ",16,_global.bss_c";
698 O << "\t.comm " << Name << "," << TD.getTypeSize(I->getType())
699 << "," << log2((unsigned)TD.getTypeAlignment(I->getType()));
702 WriteAsOperand(O, I, true, true, &M);
706 O << "_section_.text:\n"
707 << "\t.csect .data[RW],3\n"
708 << "\t.llong _section_.text\n";
711 return false; // success