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:
353 std::string Name(GlobalPrefix); Name += MO.getSymbolName();
354 FnStubs.insert(Name);
355 O << "L" << Name << "$stub";
358 O << GlobalPrefix << MO.getSymbolName();
361 case MachineOperand::MO_GlobalAddress: {
362 GlobalValue *GV = MO.getGlobal();
363 std::string Name = Mang->getValueName(GV);
365 // Dynamically-resolved functions need a stub for the function. Be
366 // wary however not to output $stub for external functions whose addresses
367 // are taken. Those should be emitted as $non_lazy_ptr below.
368 Function *F = dyn_cast<Function>(GV);
369 if (F && IsCallOp && F->isExternal()) {
370 FnStubs.insert(Name);
371 O << "L" << Name << "$stub";
375 // External or weakly linked global variables need non-lazily-resolved stubs
376 if ((GV->isExternal() || GV->hasWeakLinkage() || GV->hasLinkOnceLinkage())){
377 if (GV->hasLinkOnceLinkage())
378 LinkOnceStubs.insert(Name);
380 GVStubs.insert(Name);
381 O << "L" << Name << "$non_lazy_ptr";
385 O << Mang->getValueName(GV);
390 O << "<unknown operand type: " << MO.getType() << ">";
395 /// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to
396 /// the current output stream.
398 void PowerPCAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
400 if (printInstruction(MI))
401 return; // Printer was automatically generated
403 assert(0 && "Unhandled instruction in asm writer!");
408 /// runOnMachineFunction - This uses the printMachineInstruction()
409 /// method to print assembly for each instruction.
411 bool DarwinAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
412 setupMachineFunction(MF);
415 // Print out constants referenced by the function
416 printConstantPool(MF.getConstantPool());
418 // Print out labels for the function.
421 O << "\t.globl\t" << CurrentFnName << "\n";
422 O << CurrentFnName << ":\n";
424 // Print out code for the function.
425 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
427 // Print a label for the basic block.
428 O << ".LBB" << CurrentFnName << "_" << I->getNumber() << ":\t"
429 << CommentString << " " << I->getBasicBlock()->getName() << "\n";
430 for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
432 // Print the assembly for the instruction.
434 printMachineInstruction(II);
439 // We didn't modify anything.
443 /// printConstantPool - Print to the current output stream assembly
444 /// representations of the constants in the constant pool MCP. This is
445 /// used to print out constants which have been "spilled to memory" by
446 /// the code generator.
448 void DarwinAsmPrinter::printConstantPool(MachineConstantPool *MCP) {
449 const std::vector<Constant*> &CP = MCP->getConstants();
450 const TargetData &TD = TM.getTargetData();
452 if (CP.empty()) return;
454 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
456 emitAlignment(TD.getTypeAlignmentShift(CP[i]->getType()));
457 O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t" << CommentString
459 emitGlobalConstant(CP[i]);
463 bool DarwinAsmPrinter::doFinalization(Module &M) {
464 const TargetData &TD = TM.getTargetData();
465 std::string CurSection;
467 // Print out module-level global variables here.
468 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I)
469 if (I->hasInitializer()) { // External global require no code
471 std::string name = Mang->getValueName(I);
472 Constant *C = I->getInitializer();
473 unsigned Size = TD.getTypeSize(C->getType());
474 unsigned Align = TD.getTypeAlignmentShift(C->getType());
476 if (C->isNullValue() && /* FIXME: Verify correct */
477 (I->hasInternalLinkage() || I->hasWeakLinkage() ||
478 I->hasLinkOnceLinkage())) {
479 SwitchSection(O, CurSection, ".data");
480 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
481 if (I->hasInternalLinkage())
482 O << ".lcomm " << name << "," << Size << "," << Align;
484 O << ".comm " << name << "," << Size;
486 WriteAsOperand(O, I, true, true, &M);
489 switch (I->getLinkage()) {
490 case GlobalValue::LinkOnceLinkage:
491 O << ".section __TEXT,__textcoal_nt,coalesced,no_toc\n"
492 << ".weak_definition " << name << '\n'
493 << ".private_extern " << name << '\n'
494 << ".section __DATA,__datacoal_nt,coalesced,no_toc\n";
495 LinkOnceStubs.insert(name);
497 case GlobalValue::WeakLinkage: // FIXME: Verify correct for weak.
498 // Nonnull linkonce -> weak
499 O << "\t.weak " << name << "\n";
500 SwitchSection(O, CurSection, "");
501 O << "\t.section\t.llvm.linkonce.d." << name << ",\"aw\",@progbits\n";
503 case GlobalValue::AppendingLinkage:
504 // FIXME: appending linkage variables should go into a section of
505 // their name or something. For now, just emit them as external.
506 case GlobalValue::ExternalLinkage:
507 // If external or appending, declare as a global symbol
508 O << "\t.globl " << name << "\n";
510 case GlobalValue::InternalLinkage:
511 SwitchSection(O, CurSection, ".data");
513 case GlobalValue::GhostLinkage:
514 std::cerr << "Error: unmaterialized (GhostLinkage) function in asm!";
518 emitAlignment(Align);
519 O << name << ":\t\t\t\t; ";
520 WriteAsOperand(O, I, true, true, &M);
522 WriteAsOperand(O, C, false, false, &M);
524 emitGlobalConstant(C);
528 // Output stubs for dynamically-linked functions
529 for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
533 O << ".section __TEXT,__picsymbolstub1,symbol_stubs,pure_instructions,32\n";
535 O << "L" << *i << "$stub:\n";
536 O << "\t.indirect_symbol " << *i << "\n";
538 O << "\tbcl 20,31,L0$" << *i << "\n";
539 O << "L0$" << *i << ":\n";
541 O << "\taddis r11,r11,ha16(L" << *i << "$lazy_ptr-L0$" << *i << ")\n";
543 O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
544 O << "\tmtctr r12\n";
547 O << ".lazy_symbol_pointer\n";
548 O << "L" << *i << "$lazy_ptr:\n";
549 O << "\t.indirect_symbol " << *i << "\n";
550 O << "\t.long dyld_stub_binding_helper\n";
555 // Output stubs for external global variables
556 if (GVStubs.begin() != GVStubs.end())
557 O << ".data\n.non_lazy_symbol_pointer\n";
558 for (std::set<std::string>::iterator i = GVStubs.begin(), e = GVStubs.end();
560 O << "L" << *i << "$non_lazy_ptr:\n";
561 O << "\t.indirect_symbol " << *i << "\n";
565 // Output stubs for link-once variables
566 if (LinkOnceStubs.begin() != LinkOnceStubs.end())
567 O << ".data\n.align 2\n";
568 for (std::set<std::string>::iterator i = LinkOnceStubs.begin(),
569 e = LinkOnceStubs.end(); i != e; ++i) {
570 O << "L" << *i << "$non_lazy_ptr:\n"
571 << "\t.long\t" << *i << '\n';
574 AsmPrinter::doFinalization(M);
575 return false; // success
578 /// runOnMachineFunction - This uses the printMachineInstruction()
579 /// method to print assembly for each instruction.
581 bool AIXAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
582 CurrentFnName = MF.getFunction()->getName();
584 // Print out constants referenced by the function
585 printConstantPool(MF.getConstantPool());
587 // Print out header for the function.
588 O << "\t.csect .text[PR]\n"
590 << "\t.globl " << CurrentFnName << '\n'
591 << "\t.globl ." << CurrentFnName << '\n'
592 << "\t.csect " << CurrentFnName << "[DS],3\n"
593 << CurrentFnName << ":\n"
594 << "\t.llong ." << CurrentFnName << ", TOC[tc0], 0\n"
595 << "\t.csect .text[PR]\n"
596 << '.' << CurrentFnName << ":\n";
598 // Print out code for the function.
599 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
601 // Print a label for the basic block.
602 O << "LBB" << CurrentFnName << "_" << I->getNumber() << ":\t# "
603 << I->getBasicBlock()->getName() << "\n";
604 for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
606 // Print the assembly for the instruction.
608 printMachineInstruction(II);
613 O << "LT.." << CurrentFnName << ":\n"
615 << "\t.byte 0,0,32,65,128,0,0,0\n"
616 << "\t.long LT.." << CurrentFnName << "-." << CurrentFnName << '\n'
618 << "\t.byte \"" << CurrentFnName << "\"\n"
621 // We didn't modify anything.
625 /// printConstantPool - Print to the current output stream assembly
626 /// representations of the constants in the constant pool MCP. This is
627 /// used to print out constants which have been "spilled to memory" by
628 /// the code generator.
630 void AIXAsmPrinter::printConstantPool(MachineConstantPool *MCP) {
631 const std::vector<Constant*> &CP = MCP->getConstants();
632 const TargetData &TD = TM.getTargetData();
634 if (CP.empty()) return;
636 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
638 O << "\t.align " << (unsigned)TD.getTypeAlignment(CP[i]->getType())
640 O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t;"
642 emitGlobalConstant(CP[i]);
646 bool AIXAsmPrinter::doInitialization(Module &M) {
647 const TargetData &TD = TM.getTargetData();
648 std::string CurSection;
650 O << "\t.machine \"ppc64\"\n"
652 << "\t.csect .text[PR]\n";
654 // Print out module-level global variables
655 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) {
656 if (!I->hasInitializer())
659 std::string Name = I->getName();
660 Constant *C = I->getInitializer();
661 // N.B.: We are defaulting to writable strings
662 if (I->hasExternalLinkage()) {
663 O << "\t.globl " << Name << '\n'
664 << "\t.csect .data[RW],3\n";
666 O << "\t.csect _global.rw_c[RW],3\n";
669 emitGlobalConstant(C);
672 // Output labels for globals
673 if (M.global_begin() != M.global_end()) O << "\t.toc\n";
674 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) {
675 const GlobalVariable *GV = I;
676 // Do not output labels for unused variables
677 if (GV->isExternal() && GV->use_begin() == GV->use_end())
680 std::string Name = GV->getName();
681 std::string Label = "LC.." + utostr(LabelNumber++);
682 GVToLabelMap[GV] = Label;
684 << "\t.tc " << Name << "[TC]," << Name;
685 if (GV->isExternal()) O << "[RW]";
689 Mang = new Mangler(M, ".");
690 return false; // success
693 bool AIXAsmPrinter::doFinalization(Module &M) {
694 const TargetData &TD = TM.getTargetData();
695 // Print out module-level global variables
696 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) {
697 if (I->hasInitializer() || I->hasExternalLinkage())
700 std::string Name = I->getName();
701 if (I->hasInternalLinkage()) {
702 O << "\t.lcomm " << Name << ",16,_global.bss_c";
704 O << "\t.comm " << Name << "," << TD.getTypeSize(I->getType())
705 << "," << log2((unsigned)TD.getTypeAlignment(I->getType()));
708 WriteAsOperand(O, I, true, true, &M);
712 O << "_section_.text:\n"
713 << "\t.csect .data[RW],3\n"
714 << "\t.llong _section_.text\n";
717 return false; // success