1 //===-- PTXAsmPrinter.cpp - PTX LLVM assembly writer ----------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file contains a printer that converts from our internal representation
11 // of machine-dependent LLVM code to PTX assembly language.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #define DEBUG_TYPE "ptx-asm-printer"
16
17 #include "PTX.h"
18 #include "PTXAsmPrinter.h"
19 #include "PTXMachineFunctionInfo.h"
20 #include "PTXParamManager.h"
21 #include "PTXRegisterInfo.h"
22 #include "PTXTargetMachine.h"
23 #include "llvm/Argument.h"
24 #include "llvm/DerivedTypes.h"
25 #include "llvm/Function.h"
26 #include "llvm/Module.h"
27 #include "llvm/ADT/SmallString.h"
28 #include "llvm/ADT/StringExtras.h"
29 #include "llvm/ADT/Twine.h"
30 #include "llvm/Analysis/DebugInfo.h"
31 #include "llvm/CodeGen/AsmPrinter.h"
32 #include "llvm/CodeGen/MachineFrameInfo.h"
33 #include "llvm/CodeGen/MachineInstr.h"
34 #include "llvm/CodeGen/MachineRegisterInfo.h"
35 #include "llvm/MC/MCContext.h"
36 #include "llvm/MC/MCExpr.h"
37 #include "llvm/MC/MCInst.h"
38 #include "llvm/MC/MCStreamer.h"
39 #include "llvm/MC/MCSymbol.h"
40 #include "llvm/Target/Mangler.h"
41 #include "llvm/Target/TargetLoweringObjectFile.h"
42 #include "llvm/Support/CommandLine.h"
43 #include "llvm/Support/Debug.h"
44 #include "llvm/Support/ErrorHandling.h"
45 #include "llvm/Support/MathExtras.h"
46 #include "llvm/Support/Path.h"
47 #include "llvm/Support/TargetRegistry.h"
48 #include "llvm/Support/raw_ostream.h"
49
50 using namespace llvm;
51
52 static const char PARAM_PREFIX[] = "__param_";
53 static const char RETURN_PREFIX[] = "__ret_";
54
getRegisterTypeName(unsigned RegNo,const MachineRegisterInfo & MRI)55 static const char *getRegisterTypeName(unsigned RegNo,
56 const MachineRegisterInfo& MRI) {
57 const TargetRegisterClass *TRC = MRI.getRegClass(RegNo);
58
59 #define TEST_REGCLS(cls, clsstr) \
60 if (PTX::cls ## RegisterClass == TRC) return # clsstr;
61
62 TEST_REGCLS(RegPred, pred);
63 TEST_REGCLS(RegI16, b16);
64 TEST_REGCLS(RegI32, b32);
65 TEST_REGCLS(RegI64, b64);
66 TEST_REGCLS(RegF32, b32);
67 TEST_REGCLS(RegF64, b64);
68 #undef TEST_REGCLS
69
70 llvm_unreachable("Not in any register class!");
71 return NULL;
72 }
73
getStateSpaceName(unsigned addressSpace)74 static const char *getStateSpaceName(unsigned addressSpace) {
75 switch (addressSpace) {
76 default: llvm_unreachable("Unknown state space");
77 case PTXStateSpace::Global: return "global";
78 case PTXStateSpace::Constant: return "const";
79 case PTXStateSpace::Local: return "local";
80 case PTXStateSpace::Parameter: return "param";
81 case PTXStateSpace::Shared: return "shared";
82 }
83 return NULL;
84 }
85
getTypeName(Type * type)86 static const char *getTypeName(Type* type) {
87 while (true) {
88 switch (type->getTypeID()) {
89 default: llvm_unreachable("Unknown type");
90 case Type::FloatTyID: return ".f32";
91 case Type::DoubleTyID: return ".f64";
92 case Type::IntegerTyID:
93 switch (type->getPrimitiveSizeInBits()) {
94 default: llvm_unreachable("Unknown integer bit-width");
95 case 16: return ".u16";
96 case 32: return ".u32";
97 case 64: return ".u64";
98 }
99 case Type::ArrayTyID:
100 case Type::PointerTyID:
101 type = dyn_cast<SequentialType>(type)->getElementType();
102 break;
103 }
104 }
105 return NULL;
106 }
107
doFinalization(Module & M)108 bool PTXAsmPrinter::doFinalization(Module &M) {
109 // XXX Temproarily remove global variables so that doFinalization() will not
110 // emit them again (global variables are emitted at beginning).
111
112 Module::GlobalListType &global_list = M.getGlobalList();
113 int i, n = global_list.size();
114 GlobalVariable **gv_array = new GlobalVariable* [n];
115
116 // first, back-up GlobalVariable in gv_array
117 i = 0;
118 for (Module::global_iterator I = global_list.begin(), E = global_list.end();
119 I != E; ++I)
120 gv_array[i++] = &*I;
121
122 // second, empty global_list
123 while (!global_list.empty())
124 global_list.remove(global_list.begin());
125
126 // call doFinalization
127 bool ret = AsmPrinter::doFinalization(M);
128
129 // now we restore global variables
130 for (i = 0; i < n; i ++)
131 global_list.insert(global_list.end(), gv_array[i]);
132
133 delete[] gv_array;
134 return ret;
135 }
136
EmitStartOfAsmFile(Module & M)137 void PTXAsmPrinter::EmitStartOfAsmFile(Module &M)
138 {
139 const PTXSubtarget& ST = TM.getSubtarget<PTXSubtarget>();
140
141 // Emit the PTX .version and .target attributes
142 OutStreamer.EmitRawText(Twine("\t.version " + ST.getPTXVersionString()));
143 OutStreamer.EmitRawText(Twine("\t.target " + ST.getTargetString() +
144 (ST.supportsDouble() ? ""
145 : ", map_f64_to_f32")));
146 // .address_size directive is optional, but it must immediately follow
147 // the .target directive if present within a module
148 if (ST.supportsPTX23()) {
149 std::string addrSize = ST.is64Bit() ? "64" : "32";
150 OutStreamer.EmitRawText(Twine("\t.address_size " + addrSize));
151 }
152
153 OutStreamer.AddBlankLine();
154
155 // Define any .file directives
156 DebugInfoFinder DbgFinder;
157 DbgFinder.processModule(M);
158
159 for (DebugInfoFinder::iterator I = DbgFinder.compile_unit_begin(),
160 E = DbgFinder.compile_unit_end(); I != E; ++I) {
161 DICompileUnit DIUnit(*I);
162 StringRef FN = DIUnit.getFilename();
163 StringRef Dir = DIUnit.getDirectory();
164 GetOrCreateSourceID(FN, Dir);
165 }
166
167 OutStreamer.AddBlankLine();
168
169 // declare global variables
170 for (Module::const_global_iterator i = M.global_begin(), e = M.global_end();
171 i != e; ++i)
172 EmitVariableDeclaration(i);
173 }
174
EmitFunctionBodyStart()175 void PTXAsmPrinter::EmitFunctionBodyStart() {
176 OutStreamer.EmitRawText(Twine("{"));
177
178 const PTXMachineFunctionInfo *MFI = MF->getInfo<PTXMachineFunctionInfo>();
179 const PTXParamManager &PM = MFI->getParamManager();
180
181 // Print register definitions
182 std::string regDefs;
183 unsigned numRegs;
184
185 // pred
186 numRegs = MFI->getNumRegistersForClass(PTX::RegPredRegisterClass);
187 if(numRegs > 0) {
188 regDefs += "\t.reg .pred %p<";
189 regDefs += utostr(numRegs);
190 regDefs += ">;\n";
191 }
192
193 // i16
194 numRegs = MFI->getNumRegistersForClass(PTX::RegI16RegisterClass);
195 if(numRegs > 0) {
196 regDefs += "\t.reg .b16 %rh<";
197 regDefs += utostr(numRegs);
198 regDefs += ">;\n";
199 }
200
201 // i32
202 numRegs = MFI->getNumRegistersForClass(PTX::RegI32RegisterClass);
203 if(numRegs > 0) {
204 regDefs += "\t.reg .b32 %r<";
205 regDefs += utostr(numRegs);
206 regDefs += ">;\n";
207 }
208
209 // i64
210 numRegs = MFI->getNumRegistersForClass(PTX::RegI64RegisterClass);
211 if(numRegs > 0) {
212 regDefs += "\t.reg .b64 %rd<";
213 regDefs += utostr(numRegs);
214 regDefs += ">;\n";
215 }
216
217 // f32
218 numRegs = MFI->getNumRegistersForClass(PTX::RegF32RegisterClass);
219 if(numRegs > 0) {
220 regDefs += "\t.reg .f32 %f<";
221 regDefs += utostr(numRegs);
222 regDefs += ">;\n";
223 }
224
225 // f64
226 numRegs = MFI->getNumRegistersForClass(PTX::RegF64RegisterClass);
227 if(numRegs > 0) {
228 regDefs += "\t.reg .f64 %fd<";
229 regDefs += utostr(numRegs);
230 regDefs += ">;\n";
231 }
232
233 // Local params
234 for (PTXParamManager::param_iterator i = PM.local_begin(), e = PM.local_end();
235 i != e; ++i) {
236 regDefs += "\t.param .b";
237 regDefs += utostr(PM.getParamSize(*i));
238 regDefs += " ";
239 regDefs += PM.getParamName(*i);
240 regDefs += ";\n";
241 }
242
243 OutStreamer.EmitRawText(Twine(regDefs));
244
245
246 const MachineFrameInfo* FrameInfo = MF->getFrameInfo();
247 DEBUG(dbgs() << "Have " << FrameInfo->getNumObjects()
248 << " frame object(s)\n");
249 for (unsigned i = 0, e = FrameInfo->getNumObjects(); i != e; ++i) {
250 DEBUG(dbgs() << "Size of object: " << FrameInfo->getObjectSize(i) << "\n");
251 if (FrameInfo->getObjectSize(i) > 0) {
252 std::string def = "\t.local .align ";
253 def += utostr(FrameInfo->getObjectAlignment(i));
254 def += " .b8";
255 def += " __local";
256 def += utostr(i);
257 def += "[";
258 def += utostr(FrameInfo->getObjectSize(i)); // Convert to bits
259 def += "]";
260 def += ";";
261 OutStreamer.EmitRawText(Twine(def));
262 }
263 }
264
265 //unsigned Index = 1;
266 // Print parameter passing params
267 //for (PTXMachineFunctionInfo::param_iterator
268 // i = MFI->paramBegin(), e = MFI->paramEnd(); i != e; ++i) {
269 // std::string def = "\t.param .b";
270 // def += utostr(*i);
271 // def += " __ret_";
272 // def += utostr(Index);
273 // Index++;
274 // def += ";";
275 // OutStreamer.EmitRawText(Twine(def));
276 //}
277 }
278
EmitFunctionBodyEnd()279 void PTXAsmPrinter::EmitFunctionBodyEnd() {
280 OutStreamer.EmitRawText(Twine("}"));
281 }
282
EmitInstruction(const MachineInstr * MI)283 void PTXAsmPrinter::EmitInstruction(const MachineInstr *MI) {
284 MCInst TmpInst;
285 LowerPTXMachineInstrToMCInst(MI, TmpInst, *this);
286 OutStreamer.EmitInstruction(TmpInst);
287 }
288
EmitVariableDeclaration(const GlobalVariable * gv)289 void PTXAsmPrinter::EmitVariableDeclaration(const GlobalVariable *gv) {
290 // Check to see if this is a special global used by LLVM, if so, emit it.
291 if (EmitSpecialLLVMGlobal(gv))
292 return;
293
294 MCSymbol *gvsym = Mang->getSymbol(gv);
295
296 assert(gvsym->isUndefined() && "Cannot define a symbol twice!");
297
298 std::string decl;
299
300 // check if it is defined in some other translation unit
301 if (gv->isDeclaration())
302 decl += ".extern ";
303
304 // state space: e.g., .global
305 decl += ".";
306 decl += getStateSpaceName(gv->getType()->getAddressSpace());
307 decl += " ";
308
309 // alignment (optional)
310 unsigned alignment = gv->getAlignment();
311 if (alignment != 0) {
312 decl += ".align ";
313 decl += utostr(gv->getAlignment());
314 decl += " ";
315 }
316
317
318 if (PointerType::classof(gv->getType())) {
319 PointerType* pointerTy = dyn_cast<PointerType>(gv->getType());
320 Type* elementTy = pointerTy->getElementType();
321
322 decl += ".b8 ";
323 decl += gvsym->getName();
324 decl += "[";
325
326 if (elementTy->isArrayTy())
327 {
328 assert(elementTy->isArrayTy() && "Only pointers to arrays are supported");
329
330 ArrayType* arrayTy = dyn_cast<ArrayType>(elementTy);
331 elementTy = arrayTy->getElementType();
332
333 unsigned numElements = arrayTy->getNumElements();
334
335 while (elementTy->isArrayTy()) {
336
337 arrayTy = dyn_cast<ArrayType>(elementTy);
338 elementTy = arrayTy->getElementType();
339
340 numElements *= arrayTy->getNumElements();
341 }
342
343 // FIXME: isPrimitiveType() == false for i16?
344 assert(elementTy->isSingleValueType() &&
345 "Non-primitive types are not handled");
346
347 // Compute the size of the array, in bytes.
348 uint64_t arraySize = (elementTy->getPrimitiveSizeInBits() >> 3)
349 * numElements;
350
351 decl += utostr(arraySize);
352 }
353
354 decl += "]";
355
356 // handle string constants (assume ConstantArray means string)
357
358 if (gv->hasInitializer())
359 {
360 const Constant *C = gv->getInitializer();
361 if (const ConstantArray *CA = dyn_cast<ConstantArray>(C))
362 {
363 decl += " = {";
364
365 for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
366 {
367 if (i > 0) decl += ",";
368
369 decl += "0x" +
370 utohexstr(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
371 }
372
373 decl += "}";
374 }
375 }
376 }
377 else {
378 // Note: this is currently the fall-through case and most likely generates
379 // incorrect code.
380 decl += getTypeName(gv->getType());
381 decl += " ";
382
383 decl += gvsym->getName();
384
385 if (ArrayType::classof(gv->getType()) ||
386 PointerType::classof(gv->getType()))
387 decl += "[]";
388 }
389
390 decl += ";";
391
392 OutStreamer.EmitRawText(Twine(decl));
393
394 OutStreamer.AddBlankLine();
395 }
396
EmitFunctionEntryLabel()397 void PTXAsmPrinter::EmitFunctionEntryLabel() {
398 // The function label could have already been emitted if two symbols end up
399 // conflicting due to asm renaming. Detect this and emit an error.
400 if (!CurrentFnSym->isUndefined()) {
401 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
402 "' label emitted multiple times to assembly file");
403 return;
404 }
405
406 const PTXMachineFunctionInfo *MFI = MF->getInfo<PTXMachineFunctionInfo>();
407 const PTXParamManager &PM = MFI->getParamManager();
408 const bool isKernel = MFI->isKernel();
409 const PTXSubtarget& ST = TM.getSubtarget<PTXSubtarget>();
410 const MachineRegisterInfo& MRI = MF->getRegInfo();
411
412 std::string decl = isKernel ? ".entry" : ".func";
413
414 if (!isKernel) {
415 decl += " (";
416 if (ST.useParamSpaceForDeviceArgs()) {
417 for (PTXParamManager::param_iterator i = PM.ret_begin(), e = PM.ret_end(),
418 b = i; i != e; ++i) {
419 if (i != b) {
420 decl += ", ";
421 }
422
423 decl += ".param .b";
424 decl += utostr(PM.getParamSize(*i));
425 decl += " ";
426 decl += PM.getParamName(*i);
427 }
428 } else {
429 for (PTXMachineFunctionInfo::reg_iterator
430 i = MFI->retreg_begin(), e = MFI->retreg_end(), b = i;
431 i != e; ++i) {
432 if (i != b) {
433 decl += ", ";
434 }
435 decl += ".reg .";
436 decl += getRegisterTypeName(*i, MRI);
437 decl += " ";
438 decl += MFI->getRegisterName(*i);
439 }
440 }
441 decl += ")";
442 }
443
444 // Print function name
445 decl += " ";
446 decl += CurrentFnSym->getName().str();
447
448 decl += " (";
449
450 const Function *F = MF->getFunction();
451
452 // Print parameters
453 if (isKernel || ST.useParamSpaceForDeviceArgs()) {
454 /*for (PTXParamManager::param_iterator i = PM.arg_begin(), e = PM.arg_end(),
455 b = i; i != e; ++i) {
456 if (i != b) {
457 decl += ", ";
458 }
459
460 decl += ".param .b";
461 decl += utostr(PM.getParamSize(*i));
462 decl += " ";
463 decl += PM.getParamName(*i);
464 }*/
465 int Counter = 1;
466 for (Function::const_arg_iterator i = F->arg_begin(), e = F->arg_end(),
467 b = i; i != e; ++i) {
468 if (i != b)
469 decl += ", ";
470 const Type *ArgType = (*i).getType();
471 decl += ".param .b";
472 if (ArgType->isPointerTy()) {
473 if (ST.is64Bit())
474 decl += "64";
475 else
476 decl += "32";
477 } else {
478 decl += utostr(ArgType->getPrimitiveSizeInBits());
479 }
480 if (ArgType->isPointerTy() && ST.emitPtrAttribute()) {
481 const PointerType *PtrType = dyn_cast<const PointerType>(ArgType);
482 decl += " .ptr";
483 switch (PtrType->getAddressSpace()) {
484 default:
485 llvm_unreachable("Unknown address space in argument");
486 case PTXStateSpace::Global:
487 decl += " .global";
488 break;
489 case PTXStateSpace::Shared:
490 decl += " .shared";
491 break;
492 }
493 }
494 decl += " __param_";
495 decl += utostr(Counter++);
496 }
497 } else {
498 for (PTXMachineFunctionInfo::reg_iterator
499 i = MFI->argreg_begin(), e = MFI->argreg_end(), b = i;
500 i != e; ++i) {
501 if (i != b) {
502 decl += ", ";
503 }
504
505 decl += ".reg .";
506 decl += getRegisterTypeName(*i, MRI);
507 decl += " ";
508 decl += MFI->getRegisterName(*i);
509 }
510 }
511 decl += ")";
512
513 OutStreamer.EmitRawText(Twine(decl));
514 }
515
GetOrCreateSourceID(StringRef FileName,StringRef DirName)516 unsigned PTXAsmPrinter::GetOrCreateSourceID(StringRef FileName,
517 StringRef DirName) {
518 // If FE did not provide a file name, then assume stdin.
519 if (FileName.empty())
520 return GetOrCreateSourceID("<stdin>", StringRef());
521
522 // MCStream expects full path name as filename.
523 if (!DirName.empty() && !sys::path::is_absolute(FileName)) {
524 SmallString<128> FullPathName = DirName;
525 sys::path::append(FullPathName, FileName);
526 // Here FullPathName will be copied into StringMap by GetOrCreateSourceID.
527 return GetOrCreateSourceID(StringRef(FullPathName), StringRef());
528 }
529
530 StringMapEntry<unsigned> &Entry = SourceIdMap.GetOrCreateValue(FileName);
531 if (Entry.getValue())
532 return Entry.getValue();
533
534 unsigned SrcId = SourceIdMap.size();
535 Entry.setValue(SrcId);
536
537 // Print out a .file directive to specify files for .loc directives.
538 OutStreamer.EmitDwarfFileDirective(SrcId, Entry.getKey());
539
540 return SrcId;
541 }
542
GetSymbolRef(const MachineOperand & MO,const MCSymbol * Symbol)543 MCOperand PTXAsmPrinter::GetSymbolRef(const MachineOperand &MO,
544 const MCSymbol *Symbol) {
545 const MCExpr *Expr;
546 Expr = MCSymbolRefExpr::Create(Symbol, MCSymbolRefExpr::VK_None, OutContext);
547 return MCOperand::CreateExpr(Expr);
548 }
549
lowerOperand(const MachineOperand & MO)550 MCOperand PTXAsmPrinter::lowerOperand(const MachineOperand &MO) {
551 MCOperand MCOp;
552 const PTXMachineFunctionInfo *MFI = MF->getInfo<PTXMachineFunctionInfo>();
553 const MCExpr *Expr;
554 const char *RegSymbolName;
555 switch (MO.getType()) {
556 default:
557 llvm_unreachable("Unknown operand type");
558 case MachineOperand::MO_Register:
559 // We create register operands as symbols, since the PTXInstPrinter class
560 // has no way to map virtual registers back to a name without some ugly
561 // hacks.
562 // FIXME: Figure out a better way to handle virtual register naming.
563 RegSymbolName = MFI->getRegisterName(MO.getReg());
564 Expr = MCSymbolRefExpr::Create(RegSymbolName, MCSymbolRefExpr::VK_None,
565 OutContext);
566 MCOp = MCOperand::CreateExpr(Expr);
567 break;
568 case MachineOperand::MO_Immediate:
569 MCOp = MCOperand::CreateImm(MO.getImm());
570 break;
571 case MachineOperand::MO_MachineBasicBlock:
572 MCOp = MCOperand::CreateExpr(MCSymbolRefExpr::Create(
573 MO.getMBB()->getSymbol(), OutContext));
574 break;
575 case MachineOperand::MO_GlobalAddress:
576 MCOp = GetSymbolRef(MO, Mang->getSymbol(MO.getGlobal()));
577 break;
578 case MachineOperand::MO_ExternalSymbol:
579 MCOp = GetSymbolRef(MO, GetExternalSymbolSymbol(MO.getSymbolName()));
580 break;
581 case MachineOperand::MO_FPImmediate:
582 APFloat Val = MO.getFPImm()->getValueAPF();
583 bool ignored;
584 Val.convert(APFloat::IEEEdouble, APFloat::rmTowardZero, &ignored);
585 MCOp = MCOperand::CreateFPImm(Val.convertToDouble());
586 break;
587 }
588
589 return MCOp;
590 }
591
592 // Force static initialization.
LLVMInitializePTXAsmPrinter()593 extern "C" void LLVMInitializePTXAsmPrinter() {
594 RegisterAsmPrinter<PTXAsmPrinter> X(ThePTX32Target);
595 RegisterAsmPrinter<PTXAsmPrinter> Y(ThePTX64Target);
596 }
597
598