1 //===-- XCoreAsmPrinter.cpp - XCore 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 the XAS-format XCore assembly language.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #define DEBUG_TYPE "asm-printer"
16 #include "XCore.h"
17 #include "InstPrinter/XCoreInstPrinter.h"
18 #include "XCoreInstrInfo.h"
19 #include "XCoreMCInstLower.h"
20 #include "XCoreSubtarget.h"
21 #include "XCoreTargetMachine.h"
22 #include "llvm/ADT/SmallString.h"
23 #include "llvm/ADT/StringExtras.h"
24 #include "llvm/CodeGen/AsmPrinter.h"
25 #include "llvm/CodeGen/MachineConstantPool.h"
26 #include "llvm/CodeGen/MachineFunctionPass.h"
27 #include "llvm/CodeGen/MachineInstr.h"
28 #include "llvm/CodeGen/MachineJumpTableInfo.h"
29 #include "llvm/CodeGen/MachineModuleInfo.h"
30 #include "llvm/DebugInfo.h"
31 #include "llvm/IR/Constants.h"
32 #include "llvm/IR/DataLayout.h"
33 #include "llvm/IR/DerivedTypes.h"
34 #include "llvm/IR/Module.h"
35 #include "llvm/MC/MCAsmInfo.h"
36 #include "llvm/MC/MCInst.h"
37 #include "llvm/MC/MCStreamer.h"
38 #include "llvm/MC/MCSymbol.h"
39 #include "llvm/Support/CommandLine.h"
40 #include "llvm/Support/ErrorHandling.h"
41 #include "llvm/Support/TargetRegistry.h"
42 #include "llvm/Support/raw_ostream.h"
43 #include "llvm/Target/Mangler.h"
44 #include "llvm/Target/TargetLoweringObjectFile.h"
45 #include <algorithm>
46 #include <cctype>
47 using namespace llvm;
48
49 static cl::opt<unsigned> MaxThreads("xcore-max-threads", cl::Optional,
50 cl::desc("Maximum number of threads (for emulation thread-local storage)"),
51 cl::Hidden,
52 cl::value_desc("number"),
53 cl::init(8));
54
55 namespace {
56 class XCoreAsmPrinter : public AsmPrinter {
57 const XCoreSubtarget &Subtarget;
58 XCoreMCInstLower MCInstLowering;
59 void PrintDebugValueComment(const MachineInstr *MI, raw_ostream &OS);
60 public:
XCoreAsmPrinter(TargetMachine & TM,MCStreamer & Streamer)61 explicit XCoreAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
62 : AsmPrinter(TM, Streamer), Subtarget(TM.getSubtarget<XCoreSubtarget>()),
63 MCInstLowering(*this) {}
64
getPassName() const65 virtual const char *getPassName() const {
66 return "XCore Assembly Printer";
67 }
68
69 void printInlineJT(const MachineInstr *MI, int opNum, raw_ostream &O,
70 const std::string &directive = ".jmptable");
printInlineJT32(const MachineInstr * MI,int opNum,raw_ostream & O)71 void printInlineJT32(const MachineInstr *MI, int opNum, raw_ostream &O) {
72 printInlineJT(MI, opNum, O, ".jmptable32");
73 }
74 void printOperand(const MachineInstr *MI, int opNum, raw_ostream &O);
75 bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
76 unsigned AsmVariant, const char *ExtraCode,
77 raw_ostream &O);
78
79 void emitArrayBound(MCSymbol *Sym, const GlobalVariable *GV);
80 virtual void EmitGlobalVariable(const GlobalVariable *GV);
81
82 void EmitFunctionEntryLabel();
83 void EmitInstruction(const MachineInstr *MI);
84 void EmitFunctionBodyStart();
85 void EmitFunctionBodyEnd();
86 virtual MachineLocation getDebugValueLocation(const MachineInstr *MI) const;
87 };
88 } // end of anonymous namespace
89
emitArrayBound(MCSymbol * Sym,const GlobalVariable * GV)90 void XCoreAsmPrinter::emitArrayBound(MCSymbol *Sym, const GlobalVariable *GV) {
91 assert(((GV->hasExternalLinkage() ||
92 GV->hasWeakLinkage()) ||
93 GV->hasLinkOnceLinkage()) && "Unexpected linkage");
94 if (ArrayType *ATy = dyn_cast<ArrayType>(
95 cast<PointerType>(GV->getType())->getElementType())) {
96 OutStreamer.EmitSymbolAttribute(Sym, MCSA_Global);
97 // FIXME: MCStreamerize.
98 OutStreamer.EmitRawText(StringRef(".globound"));
99 OutStreamer.EmitRawText("\t.set\t" + Twine(Sym->getName()));
100 OutStreamer.EmitRawText(".globound," + Twine(ATy->getNumElements()));
101 if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage()) {
102 // TODO Use COMDAT groups for LinkOnceLinkage
103 OutStreamer.EmitRawText(MAI->getWeakDefDirective() +Twine(Sym->getName())+
104 ".globound");
105 }
106 }
107 }
108
EmitGlobalVariable(const GlobalVariable * GV)109 void XCoreAsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
110 // Check to see if this is a special global used by LLVM, if so, emit it.
111 if (!GV->hasInitializer() ||
112 EmitSpecialLLVMGlobal(GV))
113 return;
114
115 const DataLayout *TD = TM.getDataLayout();
116 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(GV, Mang,TM));
117
118
119 MCSymbol *GVSym = Mang->getSymbol(GV);
120 const Constant *C = GV->getInitializer();
121 unsigned Align = (unsigned)TD->getPreferredTypeAlignmentShift(C->getType());
122
123 // Mark the start of the global
124 OutStreamer.EmitRawText("\t.cc_top " + Twine(GVSym->getName()) + ".data," +
125 GVSym->getName());
126
127 switch (GV->getLinkage()) {
128 case GlobalValue::AppendingLinkage:
129 report_fatal_error("AppendingLinkage is not supported by this target!");
130 case GlobalValue::LinkOnceAnyLinkage:
131 case GlobalValue::LinkOnceODRLinkage:
132 case GlobalValue::WeakAnyLinkage:
133 case GlobalValue::WeakODRLinkage:
134 case GlobalValue::ExternalLinkage:
135 emitArrayBound(GVSym, GV);
136 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
137
138 // TODO Use COMDAT groups for LinkOnceLinkage
139 if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage())
140 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
141 // FALL THROUGH
142 case GlobalValue::InternalLinkage:
143 case GlobalValue::PrivateLinkage:
144 break;
145 case GlobalValue::DLLImportLinkage:
146 llvm_unreachable("DLLImport linkage is not supported by this target!");
147 case GlobalValue::DLLExportLinkage:
148 llvm_unreachable("DLLExport linkage is not supported by this target!");
149 default:
150 llvm_unreachable("Unknown linkage type!");
151 }
152
153 EmitAlignment(Align > 2 ? Align : 2, GV);
154
155 unsigned Size = TD->getTypeAllocSize(C->getType());
156 if (GV->isThreadLocal()) {
157 Size *= MaxThreads;
158 }
159 if (MAI->hasDotTypeDotSizeDirective()) {
160 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
161 OutStreamer.EmitRawText("\t.size " + Twine(GVSym->getName()) + "," +
162 Twine(Size));
163 }
164 OutStreamer.EmitLabel(GVSym);
165
166 EmitGlobalConstant(C);
167 if (GV->isThreadLocal()) {
168 for (unsigned i = 1; i < MaxThreads; ++i)
169 EmitGlobalConstant(C);
170 }
171 // The ABI requires that unsigned scalar types smaller than 32 bits
172 // are padded to 32 bits.
173 if (Size < 4)
174 OutStreamer.EmitZeros(4 - Size);
175
176 // Mark the end of the global
177 OutStreamer.EmitRawText("\t.cc_bottom " + Twine(GVSym->getName()) + ".data");
178 }
179
EmitFunctionBodyStart()180 void XCoreAsmPrinter::EmitFunctionBodyStart() {
181 MCInstLowering.Initialize(Mang, &MF->getContext());
182 }
183
184 /// EmitFunctionBodyEnd - Targets can override this to emit stuff after
185 /// the last basic block in the function.
EmitFunctionBodyEnd()186 void XCoreAsmPrinter::EmitFunctionBodyEnd() {
187 // Emit function end directives
188 OutStreamer.EmitRawText("\t.cc_bottom " + Twine(CurrentFnSym->getName()) +
189 ".function");
190 }
191
EmitFunctionEntryLabel()192 void XCoreAsmPrinter::EmitFunctionEntryLabel() {
193 // Mark the start of the function
194 OutStreamer.EmitRawText("\t.cc_top " + Twine(CurrentFnSym->getName()) +
195 ".function," + CurrentFnSym->getName());
196 OutStreamer.EmitLabel(CurrentFnSym);
197 }
198
199 void XCoreAsmPrinter::
printInlineJT(const MachineInstr * MI,int opNum,raw_ostream & O,const std::string & directive)200 printInlineJT(const MachineInstr *MI, int opNum, raw_ostream &O,
201 const std::string &directive) {
202 unsigned JTI = MI->getOperand(opNum).getIndex();
203 const MachineFunction *MF = MI->getParent()->getParent();
204 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
205 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
206 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
207 O << "\t" << directive << " ";
208 for (unsigned i = 0, e = JTBBs.size(); i != e; ++i) {
209 MachineBasicBlock *MBB = JTBBs[i];
210 if (i > 0)
211 O << ",";
212 O << *MBB->getSymbol();
213 }
214 }
215
printOperand(const MachineInstr * MI,int opNum,raw_ostream & O)216 void XCoreAsmPrinter::printOperand(const MachineInstr *MI, int opNum,
217 raw_ostream &O) {
218 const MachineOperand &MO = MI->getOperand(opNum);
219 switch (MO.getType()) {
220 case MachineOperand::MO_Register:
221 O << XCoreInstPrinter::getRegisterName(MO.getReg());
222 break;
223 case MachineOperand::MO_Immediate:
224 O << MO.getImm();
225 break;
226 case MachineOperand::MO_MachineBasicBlock:
227 O << *MO.getMBB()->getSymbol();
228 break;
229 case MachineOperand::MO_GlobalAddress:
230 O << *Mang->getSymbol(MO.getGlobal());
231 break;
232 case MachineOperand::MO_ExternalSymbol:
233 O << MO.getSymbolName();
234 break;
235 case MachineOperand::MO_ConstantPoolIndex:
236 O << MAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber()
237 << '_' << MO.getIndex();
238 break;
239 case MachineOperand::MO_JumpTableIndex:
240 O << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
241 << '_' << MO.getIndex();
242 break;
243 case MachineOperand::MO_BlockAddress:
244 O << *GetBlockAddressSymbol(MO.getBlockAddress());
245 break;
246 default:
247 llvm_unreachable("not implemented");
248 }
249 }
250
251 /// PrintAsmOperand - Print out an operand for an inline asm expression.
252 ///
PrintAsmOperand(const MachineInstr * MI,unsigned OpNo,unsigned AsmVariant,const char * ExtraCode,raw_ostream & O)253 bool XCoreAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
254 unsigned AsmVariant,const char *ExtraCode,
255 raw_ostream &O) {
256 // Does this asm operand have a single letter operand modifier?
257 if (ExtraCode && ExtraCode[0])
258 if (ExtraCode[1] != 0) return true; // Unknown modifier.
259
260 switch (ExtraCode[0]) {
261 default:
262 // See if this is a generic print operand
263 return AsmPrinter::PrintAsmOperand(MI, OpNo, AsmVariant, ExtraCode, O);
264 }
265
266 printOperand(MI, OpNo, O);
267 return false;
268 }
269
PrintDebugValueComment(const MachineInstr * MI,raw_ostream & OS)270 void XCoreAsmPrinter::PrintDebugValueComment(const MachineInstr *MI,
271 raw_ostream &OS) {
272 unsigned NOps = MI->getNumOperands();
273 assert(NOps == 4);
274 OS << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
275 // cast away const; DIetc do not take const operands for some reason.
276 DIVariable V(const_cast<MDNode *>(MI->getOperand(NOps-1).getMetadata()));
277 OS << V.getName();
278 OS << " <- ";
279 // Frame address. Currently handles register +- offset only.
280 assert(MI->getOperand(0).isReg() && MI->getOperand(1).isImm());
281 OS << '['; printOperand(MI, 0, OS); OS << '+'; printOperand(MI, 1, OS);
282 OS << ']';
283 OS << "+";
284 printOperand(MI, NOps-2, OS);
285 }
286
287 MachineLocation XCoreAsmPrinter::
getDebugValueLocation(const MachineInstr * MI) const288 getDebugValueLocation(const MachineInstr *MI) const {
289 // Handles frame addresses emitted in XCoreInstrInfo::emitFrameIndexDebugValue.
290 assert(MI->getNumOperands() == 4 && "Invalid no. of machine operands!");
291 assert(MI->getOperand(0).isReg() && MI->getOperand(1).isImm() &&
292 "Unexpected MachineOperand types");
293 return MachineLocation(MI->getOperand(0).getReg(),
294 MI->getOperand(1).getImm());
295 }
296
EmitInstruction(const MachineInstr * MI)297 void XCoreAsmPrinter::EmitInstruction(const MachineInstr *MI) {
298 SmallString<128> Str;
299 raw_svector_ostream O(Str);
300
301 switch (MI->getOpcode()) {
302 case XCore::DBG_VALUE: {
303 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
304 SmallString<128> TmpStr;
305 raw_svector_ostream OS(TmpStr);
306 PrintDebugValueComment(MI, OS);
307 OutStreamer.EmitRawText(StringRef(OS.str()));
308 }
309 return;
310 }
311 case XCore::ADD_2rus:
312 if (MI->getOperand(2).getImm() == 0) {
313 O << "\tmov "
314 << XCoreInstPrinter::getRegisterName(MI->getOperand(0).getReg()) << ", "
315 << XCoreInstPrinter::getRegisterName(MI->getOperand(1).getReg());
316 OutStreamer.EmitRawText(O.str());
317 return;
318 }
319 break;
320 case XCore::BR_JT:
321 case XCore::BR_JT32:
322 O << "\tbru "
323 << XCoreInstPrinter::getRegisterName(MI->getOperand(1).getReg()) << '\n';
324 if (MI->getOpcode() == XCore::BR_JT)
325 printInlineJT(MI, 0, O);
326 else
327 printInlineJT32(MI, 0, O);
328 O << '\n';
329 OutStreamer.EmitRawText(O.str());
330 return;
331 }
332
333 MCInst TmpInst;
334 MCInstLowering.Lower(MI, TmpInst);
335
336 OutStreamer.EmitInstruction(TmpInst);
337 }
338
339 // Force static initialization.
LLVMInitializeXCoreAsmPrinter()340 extern "C" void LLVMInitializeXCoreAsmPrinter() {
341 RegisterAsmPrinter<XCoreAsmPrinter> X(TheXCoreTarget);
342 }
343