LLVM  10.0.0svn
MCExpr.cpp
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1 //===- MCExpr.cpp - Assembly Level Expression Implementation --------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/MC/MCExpr.h"
10 #include "llvm/ADT/Statistic.h"
11 #include "llvm/ADT/StringExtras.h"
12 #include "llvm/ADT/StringSwitch.h"
13 #include "llvm/Config/llvm-config.h"
14 #include "llvm/MC/MCAsmBackend.h"
15 #include "llvm/MC/MCAsmInfo.h"
16 #include "llvm/MC/MCAsmLayout.h"
17 #include "llvm/MC/MCAssembler.h"
18 #include "llvm/MC/MCContext.h"
19 #include "llvm/MC/MCObjectWriter.h"
20 #include "llvm/MC/MCSymbol.h"
21 #include "llvm/MC/MCValue.h"
22 #include "llvm/Support/Casting.h"
23 #include "llvm/Support/Compiler.h"
24 #include "llvm/Support/Debug.h"
25 #include "llvm/Support/ErrorHandling.h"
26 #include "llvm/Support/raw_ostream.h"
27 #include <cassert>
28 #include <cstdint>
29 
30 using namespace llvm;
31 
32 #define DEBUG_TYPE "mcexpr"
33 
34 namespace {
35 namespace stats {
36 
37 STATISTIC(MCExprEvaluate, "Number of MCExpr evaluations");
38 
39 } // end namespace stats
40 } // end anonymous namespace
41 
42 void MCExpr::print(raw_ostream &OS, const MCAsmInfo *MAI, bool InParens) const {
43  switch (getKind()) {
44  case MCExpr::Target:
45  return cast<MCTargetExpr>(this)->printImpl(OS, MAI);
46  case MCExpr::Constant: {
47  auto Value = cast<MCConstantExpr>(*this).getValue();
48  auto PrintInHex = cast<MCConstantExpr>(*this).useHexFormat();
49  if (PrintInHex)
50  OS << "0x" << Twine::utohexstr(Value);
51  else
52  OS << Value;
53  return;
54  }
55  case MCExpr::SymbolRef: {
56  const MCSymbolRefExpr &SRE = cast<MCSymbolRefExpr>(*this);
57  const MCSymbol &Sym = SRE.getSymbol();
58  // Parenthesize names that start with $ so that they don't look like
59  // absolute names.
60  bool UseParens =
61  !InParens && !Sym.getName().empty() && Sym.getName()[0] == '$';
62  if (UseParens) {
63  OS << '(';
64  Sym.print(OS, MAI);
65  OS << ')';
66  } else
67  Sym.print(OS, MAI);
68 
69  if (SRE.getKind() != MCSymbolRefExpr::VK_None)
70  SRE.printVariantKind(OS);
71 
72  return;
73  }
74 
75  case MCExpr::Unary: {
76  const MCUnaryExpr &UE = cast<MCUnaryExpr>(*this);
77  switch (UE.getOpcode()) {
78  case MCUnaryExpr::LNot: OS << '!'; break;
79  case MCUnaryExpr::Minus: OS << '-'; break;
80  case MCUnaryExpr::Not: OS << '~'; break;
81  case MCUnaryExpr::Plus: OS << '+'; break;
82  }
83  bool Binary = UE.getSubExpr()->getKind() == MCExpr::Binary;
84  if (Binary) OS << "(";
85  UE.getSubExpr()->print(OS, MAI);
86  if (Binary) OS << ")";
87  return;
88  }
89 
90  case MCExpr::Binary: {
91  const MCBinaryExpr &BE = cast<MCBinaryExpr>(*this);
92 
93  // Only print parens around the LHS if it is non-trivial.
94  if (isa<MCConstantExpr>(BE.getLHS()) || isa<MCSymbolRefExpr>(BE.getLHS())) {
95  BE.getLHS()->print(OS, MAI);
96  } else {
97  OS << '(';
98  BE.getLHS()->print(OS, MAI);
99  OS << ')';
100  }
101 
102  switch (BE.getOpcode()) {
103  case MCBinaryExpr::Add:
104  // Print "X-42" instead of "X+-42".
105  if (const MCConstantExpr *RHSC = dyn_cast<MCConstantExpr>(BE.getRHS())) {
106  if (RHSC->getValue() < 0) {
107  OS << RHSC->getValue();
108  return;
109  }
110  }
111 
112  OS << '+';
113  break;
114  case MCBinaryExpr::AShr: OS << ">>"; break;
115  case MCBinaryExpr::And: OS << '&'; break;
116  case MCBinaryExpr::Div: OS << '/'; break;
117  case MCBinaryExpr::EQ: OS << "=="; break;
118  case MCBinaryExpr::GT: OS << '>'; break;
119  case MCBinaryExpr::GTE: OS << ">="; break;
120  case MCBinaryExpr::LAnd: OS << "&&"; break;
121  case MCBinaryExpr::LOr: OS << "||"; break;
122  case MCBinaryExpr::LShr: OS << ">>"; break;
123  case MCBinaryExpr::LT: OS << '<'; break;
124  case MCBinaryExpr::LTE: OS << "<="; break;
125  case MCBinaryExpr::Mod: OS << '%'; break;
126  case MCBinaryExpr::Mul: OS << '*'; break;
127  case MCBinaryExpr::NE: OS << "!="; break;
128  case MCBinaryExpr::Or: OS << '|'; break;
129  case MCBinaryExpr::Shl: OS << "<<"; break;
130  case MCBinaryExpr::Sub: OS << '-'; break;
131  case MCBinaryExpr::Xor: OS << '^'; break;
132  }
133 
134  // Only print parens around the LHS if it is non-trivial.
135  if (isa<MCConstantExpr>(BE.getRHS()) || isa<MCSymbolRefExpr>(BE.getRHS())) {
136  BE.getRHS()->print(OS, MAI);
137  } else {
138  OS << '(';
139  BE.getRHS()->print(OS, MAI);
140  OS << ')';
141  }
142  return;
143  }
144  }
145 
146  llvm_unreachable("Invalid expression kind!");
147 }
148 
149 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
150 LLVM_DUMP_METHOD void MCExpr::dump() const {
151  dbgs() << *this;
152  dbgs() << '\n';
153 }
154 #endif
155 
156 /* *** */
157 
158 const MCBinaryExpr *MCBinaryExpr::create(Opcode Opc, const MCExpr *LHS,
159  const MCExpr *RHS, MCContext &Ctx,
160  SMLoc Loc) {
161  return new (Ctx) MCBinaryExpr(Opc, LHS, RHS, Loc);
162 }
163 
164 const MCUnaryExpr *MCUnaryExpr::create(Opcode Opc, const MCExpr *Expr,
165  MCContext &Ctx, SMLoc Loc) {
166  return new (Ctx) MCUnaryExpr(Opc, Expr, Loc);
167 }
168 
169 const MCConstantExpr *MCConstantExpr::create(int64_t Value, MCContext &Ctx,
170  bool PrintInHex) {
171  return new (Ctx) MCConstantExpr(Value, PrintInHex);
172 }
173 
174 /* *** */
175 
176 MCSymbolRefExpr::MCSymbolRefExpr(const MCSymbol *Symbol, VariantKind Kind,
177  const MCAsmInfo *MAI, SMLoc Loc)
178  : MCExpr(MCExpr::SymbolRef, Loc), Kind(Kind),
179  UseParensForSymbolVariant(MAI->useParensForSymbolVariant()),
180  HasSubsectionsViaSymbols(MAI->hasSubsectionsViaSymbols()),
181  Symbol(Symbol) {
182  assert(Symbol);
183 }
184 
185 const MCSymbolRefExpr *MCSymbolRefExpr::create(const MCSymbol *Sym,
186  VariantKind Kind,
187  MCContext &Ctx, SMLoc Loc) {
188  return new (Ctx) MCSymbolRefExpr(Sym, Kind, Ctx.getAsmInfo(), Loc);
189 }
190 
191 const MCSymbolRefExpr *MCSymbolRefExpr::create(StringRef Name, VariantKind Kind,
192  MCContext &Ctx) {
193  return create(Ctx.getOrCreateSymbol(Name), Kind, Ctx);
194 }
195 
196 StringRef MCSymbolRefExpr::getVariantKindName(VariantKind Kind) {
197  switch (Kind) {
198  case VK_Invalid: return "<<invalid>>";
199  case VK_None: return "<<none>>";
200 
201  case VK_DTPOFF: return "DTPOFF";
202  case VK_DTPREL: return "DTPREL";
203  case VK_GOT: return "GOT";
204  case VK_GOTOFF: return "GOTOFF";
205  case VK_GOTREL: return "GOTREL";
206  case VK_GOTPCREL: return "GOTPCREL";
207  case VK_GOTTPOFF: return "GOTTPOFF";
208  case VK_INDNTPOFF: return "INDNTPOFF";
209  case VK_NTPOFF: return "NTPOFF";
210  case VK_GOTNTPOFF: return "GOTNTPOFF";
211  case VK_PLT: return "PLT";
212  case VK_TLSGD: return "TLSGD";
213  case VK_TLSLD: return "TLSLD";
214  case VK_TLSLDM: return "TLSLDM";
215  case VK_TPOFF: return "TPOFF";
216  case VK_TPREL: return "TPREL";
217  case VK_TLSCALL: return "tlscall";
218  case VK_TLSDESC: return "tlsdesc";
219  case VK_TLVP: return "TLVP";
220  case VK_TLVPPAGE: return "TLVPPAGE";
221  case VK_TLVPPAGEOFF: return "TLVPPAGEOFF";
222  case VK_PAGE: return "PAGE";
223  case VK_PAGEOFF: return "PAGEOFF";
224  case VK_GOTPAGE: return "GOTPAGE";
225  case VK_GOTPAGEOFF: return "GOTPAGEOFF";
226  case VK_SECREL: return "SECREL32";
227  case VK_SIZE: return "SIZE";
228  case VK_WEAKREF: return "WEAKREF";
229  case VK_X86_ABS8: return "ABS8";
230  case VK_ARM_NONE: return "none";
231  case VK_ARM_GOT_PREL: return "GOT_PREL";
232  case VK_ARM_TARGET1: return "target1";
233  case VK_ARM_TARGET2: return "target2";
234  case VK_ARM_PREL31: return "prel31";
235  case VK_ARM_SBREL: return "sbrel";
236  case VK_ARM_TLSLDO: return "tlsldo";
237  case VK_ARM_TLSDESCSEQ: return "tlsdescseq";
238  case VK_AVR_NONE: return "none";
239  case VK_AVR_LO8: return "lo8";
240  case VK_AVR_HI8: return "hi8";
241  case VK_AVR_HLO8: return "hlo8";
242  case VK_AVR_DIFF8: return "diff8";
243  case VK_AVR_DIFF16: return "diff16";
244  case VK_AVR_DIFF32: return "diff32";
245  case VK_PPC_LO: return "l";
246  case VK_PPC_HI: return "h";
247  case VK_PPC_HA: return "ha";
248  case VK_PPC_HIGH: return "high";
249  case VK_PPC_HIGHA: return "higha";
250  case VK_PPC_HIGHER: return "higher";
251  case VK_PPC_HIGHERA: return "highera";
252  case VK_PPC_HIGHEST: return "highest";
253  case VK_PPC_HIGHESTA: return "highesta";
254  case VK_PPC_GOT_LO: return "got@l";
255  case VK_PPC_GOT_HI: return "got@h";
256  case VK_PPC_GOT_HA: return "got@ha";
257  case VK_PPC_TOCBASE: return "tocbase";
258  case VK_PPC_TOC: return "toc";
259  case VK_PPC_TOC_LO: return "toc@l";
260  case VK_PPC_TOC_HI: return "toc@h";
261  case VK_PPC_TOC_HA: return "toc@ha";
262  case VK_PPC_DTPMOD: return "dtpmod";
263  case VK_PPC_TPREL_LO: return "tprel@l";
264  case VK_PPC_TPREL_HI: return "tprel@h";
265  case VK_PPC_TPREL_HA: return "tprel@ha";
266  case VK_PPC_TPREL_HIGH: return "tprel@high";
267  case VK_PPC_TPREL_HIGHA: return "tprel@higha";
268  case VK_PPC_TPREL_HIGHER: return "tprel@higher";
269  case VK_PPC_TPREL_HIGHERA: return "tprel@highera";
270  case VK_PPC_TPREL_HIGHEST: return "tprel@highest";
271  case VK_PPC_TPREL_HIGHESTA: return "tprel@highesta";
272  case VK_PPC_DTPREL_LO: return "dtprel@l";
273  case VK_PPC_DTPREL_HI: return "dtprel@h";
274  case VK_PPC_DTPREL_HA: return "dtprel@ha";
275  case VK_PPC_DTPREL_HIGH: return "dtprel@high";
276  case VK_PPC_DTPREL_HIGHA: return "dtprel@higha";
277  case VK_PPC_DTPREL_HIGHER: return "dtprel@higher";
278  case VK_PPC_DTPREL_HIGHERA: return "dtprel@highera";
279  case VK_PPC_DTPREL_HIGHEST: return "dtprel@highest";
280  case VK_PPC_DTPREL_HIGHESTA: return "dtprel@highesta";
281  case VK_PPC_GOT_TPREL: return "got@tprel";
282  case VK_PPC_GOT_TPREL_LO: return "got@tprel@l";
283  case VK_PPC_GOT_TPREL_HI: return "got@tprel@h";
284  case VK_PPC_GOT_TPREL_HA: return "got@tprel@ha";
285  case VK_PPC_GOT_DTPREL: return "got@dtprel";
286  case VK_PPC_GOT_DTPREL_LO: return "got@dtprel@l";
287  case VK_PPC_GOT_DTPREL_HI: return "got@dtprel@h";
288  case VK_PPC_GOT_DTPREL_HA: return "got@dtprel@ha";
289  case VK_PPC_TLS: return "tls";
290  case VK_PPC_GOT_TLSGD: return "got@tlsgd";
291  case VK_PPC_GOT_TLSGD_LO: return "got@tlsgd@l";
292  case VK_PPC_GOT_TLSGD_HI: return "got@tlsgd@h";
293  case VK_PPC_GOT_TLSGD_HA: return "got@tlsgd@ha";
294  case VK_PPC_TLSGD: return "tlsgd";
295  case VK_PPC_GOT_TLSLD: return "got@tlsld";
296  case VK_PPC_GOT_TLSLD_LO: return "got@tlsld@l";
297  case VK_PPC_GOT_TLSLD_HI: return "got@tlsld@h";
298  case VK_PPC_GOT_TLSLD_HA: return "got@tlsld@ha";
299  case VK_PPC_TLSLD: return "tlsld";
300  case VK_PPC_LOCAL: return "local";
301  case VK_COFF_IMGREL32: return "IMGREL";
302  case VK_Hexagon_PCREL: return "PCREL";
303  case VK_Hexagon_LO16: return "LO16";
304  case VK_Hexagon_HI16: return "HI16";
305  case VK_Hexagon_GPREL: return "GPREL";
306  case VK_Hexagon_GD_GOT: return "GDGOT";
307  case VK_Hexagon_LD_GOT: return "LDGOT";
308  case VK_Hexagon_GD_PLT: return "GDPLT";
309  case VK_Hexagon_LD_PLT: return "LDPLT";
310  case VK_Hexagon_IE: return "IE";
311  case VK_Hexagon_IE_GOT: return "IEGOT";
312  case VK_WASM_TYPEINDEX: return "TYPEINDEX";
313  case VK_WASM_MBREL: return "MBREL";
314  case VK_WASM_TBREL: return "TBREL";
315  case VK_AMDGPU_GOTPCREL32_LO: return "gotpcrel32@lo";
316  case VK_AMDGPU_GOTPCREL32_HI: return "gotpcrel32@hi";
317  case VK_AMDGPU_REL32_LO: return "rel32@lo";
318  case VK_AMDGPU_REL32_HI: return "rel32@hi";
319  case VK_AMDGPU_REL64: return "rel64";
320  case VK_AMDGPU_ABS32_LO: return "abs32@lo";
321  case VK_AMDGPU_ABS32_HI: return "abs32@hi";
322  }
323  llvm_unreachable("Invalid variant kind");
324 }
325 
326 MCSymbolRefExpr::VariantKind
327 MCSymbolRefExpr::getVariantKindForName(StringRef Name) {
328  return StringSwitch<VariantKind>(Name.lower())
329  .Case("dtprel", VK_DTPREL)
330  .Case("dtpoff", VK_DTPOFF)
331  .Case("got", VK_GOT)
332  .Case("gotoff", VK_GOTOFF)
333  .Case("gotrel", VK_GOTREL)
334  .Case("gotpcrel", VK_GOTPCREL)
335  .Case("gottpoff", VK_GOTTPOFF)
336  .Case("indntpoff", VK_INDNTPOFF)
337  .Case("ntpoff", VK_NTPOFF)
338  .Case("gotntpoff", VK_GOTNTPOFF)
339  .Case("plt", VK_PLT)
340  .Case("tlscall", VK_TLSCALL)
341  .Case("tlsdesc", VK_TLSDESC)
342  .Case("tlsgd", VK_TLSGD)
343  .Case("tlsld", VK_TLSLD)
344  .Case("tlsldm", VK_TLSLDM)
345  .Case("tpoff", VK_TPOFF)
346  .Case("tprel", VK_TPREL)
347  .Case("tlvp", VK_TLVP)
348  .Case("tlvppage", VK_TLVPPAGE)
349  .Case("tlvppageoff", VK_TLVPPAGEOFF)
350  .Case("page", VK_PAGE)
351  .Case("pageoff", VK_PAGEOFF)
352  .Case("gotpage", VK_GOTPAGE)
353  .Case("gotpageoff", VK_GOTPAGEOFF)
354  .Case("imgrel", VK_COFF_IMGREL32)
355  .Case("secrel32", VK_SECREL)
356  .Case("size", VK_SIZE)
357  .Case("abs8", VK_X86_ABS8)
358  .Case("l", VK_PPC_LO)
359  .Case("h", VK_PPC_HI)
360  .Case("ha", VK_PPC_HA)
361  .Case("high", VK_PPC_HIGH)
362  .Case("higha", VK_PPC_HIGHA)
363  .Case("higher", VK_PPC_HIGHER)
364  .Case("highera", VK_PPC_HIGHERA)
365  .Case("highest", VK_PPC_HIGHEST)
366  .Case("highesta", VK_PPC_HIGHESTA)
367  .Case("got@l", VK_PPC_GOT_LO)
368  .Case("got@h", VK_PPC_GOT_HI)
369  .Case("got@ha", VK_PPC_GOT_HA)
370  .Case("local", VK_PPC_LOCAL)
371  .Case("tocbase", VK_PPC_TOCBASE)
372  .Case("toc", VK_PPC_TOC)
373  .Case("toc@l", VK_PPC_TOC_LO)
374  .Case("toc@h", VK_PPC_TOC_HI)
375  .Case("toc@ha", VK_PPC_TOC_HA)
376  .Case("tls", VK_PPC_TLS)
377  .Case("dtpmod", VK_PPC_DTPMOD)
378  .Case("tprel@l", VK_PPC_TPREL_LO)
379  .Case("tprel@h", VK_PPC_TPREL_HI)
380  .Case("tprel@ha", VK_PPC_TPREL_HA)
381  .Case("tprel@high", VK_PPC_TPREL_HIGH)
382  .Case("tprel@higha", VK_PPC_TPREL_HIGHA)
383  .Case("tprel@higher", VK_PPC_TPREL_HIGHER)
384  .Case("tprel@highera", VK_PPC_TPREL_HIGHERA)
385  .Case("tprel@highest", VK_PPC_TPREL_HIGHEST)
386  .Case("tprel@highesta", VK_PPC_TPREL_HIGHESTA)
387  .Case("dtprel@l", VK_PPC_DTPREL_LO)
388  .Case("dtprel@h", VK_PPC_DTPREL_HI)
389  .Case("dtprel@ha", VK_PPC_DTPREL_HA)
390  .Case("dtprel@high", VK_PPC_DTPREL_HIGH)
391  .Case("dtprel@higha", VK_PPC_DTPREL_HIGHA)
392  .Case("dtprel@higher", VK_PPC_DTPREL_HIGHER)
393  .Case("dtprel@highera", VK_PPC_DTPREL_HIGHERA)
394  .Case("dtprel@highest", VK_PPC_DTPREL_HIGHEST)
395  .Case("dtprel@highesta", VK_PPC_DTPREL_HIGHESTA)
396  .Case("got@tprel", VK_PPC_GOT_TPREL)
397  .Case("got@tprel@l", VK_PPC_GOT_TPREL_LO)
398  .Case("got@tprel@h", VK_PPC_GOT_TPREL_HI)
399  .Case("got@tprel@ha", VK_PPC_GOT_TPREL_HA)
400  .Case("got@dtprel", VK_PPC_GOT_DTPREL)
401  .Case("got@dtprel@l", VK_PPC_GOT_DTPREL_LO)
402  .Case("got@dtprel@h", VK_PPC_GOT_DTPREL_HI)
403  .Case("got@dtprel@ha", VK_PPC_GOT_DTPREL_HA)
404  .Case("got@tlsgd", VK_PPC_GOT_TLSGD)
405  .Case("got@tlsgd@l", VK_PPC_GOT_TLSGD_LO)
406  .Case("got@tlsgd@h", VK_PPC_GOT_TLSGD_HI)
407  .Case("got@tlsgd@ha", VK_PPC_GOT_TLSGD_HA)
408  .Case("got@tlsld", VK_PPC_GOT_TLSLD)
409  .Case("got@tlsld@l", VK_PPC_GOT_TLSLD_LO)
410  .Case("got@tlsld@h", VK_PPC_GOT_TLSLD_HI)
411  .Case("got@tlsld@ha", VK_PPC_GOT_TLSLD_HA)
412  .Case("gdgot", VK_Hexagon_GD_GOT)
413  .Case("gdplt", VK_Hexagon_GD_PLT)
414  .Case("iegot", VK_Hexagon_IE_GOT)
415  .Case("ie", VK_Hexagon_IE)
416  .Case("ldgot", VK_Hexagon_LD_GOT)
417  .Case("ldplt", VK_Hexagon_LD_PLT)
418  .Case("pcrel", VK_Hexagon_PCREL)
419  .Case("none", VK_ARM_NONE)
420  .Case("got_prel", VK_ARM_GOT_PREL)
421  .Case("target1", VK_ARM_TARGET1)
422  .Case("target2", VK_ARM_TARGET2)
423  .Case("prel31", VK_ARM_PREL31)
424  .Case("sbrel", VK_ARM_SBREL)
425  .Case("tlsldo", VK_ARM_TLSLDO)
426  .Case("lo8", VK_AVR_LO8)
427  .Case("hi8", VK_AVR_HI8)
428  .Case("hlo8", VK_AVR_HLO8)
429  .Case("typeindex", VK_WASM_TYPEINDEX)
430  .Case("tbrel", VK_WASM_TBREL)
431  .Case("mbrel", VK_WASM_MBREL)
432  .Case("gotpcrel32@lo", VK_AMDGPU_GOTPCREL32_LO)
433  .Case("gotpcrel32@hi", VK_AMDGPU_GOTPCREL32_HI)
434  .Case("rel32@lo", VK_AMDGPU_REL32_LO)
435  .Case("rel32@hi", VK_AMDGPU_REL32_HI)
436  .Case("rel64", VK_AMDGPU_REL64)
437  .Case("abs32@lo", VK_AMDGPU_ABS32_LO)
438  .Case("abs32@hi", VK_AMDGPU_ABS32_HI)
439  .Default(VK_Invalid);
440 }
441 
442 void MCSymbolRefExpr::printVariantKind(raw_ostream &OS) const {
443  if (UseParensForSymbolVariant)
444  OS << '(' << MCSymbolRefExpr::getVariantKindName(getKind()) << ')';
445  else
446  OS << '@' << MCSymbolRefExpr::getVariantKindName(getKind());
447 }
448 
449 /* *** */
450 
451 void MCTargetExpr::anchor() {}
452 
453 /* *** */
454 
455 bool MCExpr::evaluateAsAbsolute(int64_t &Res) const {
456  return evaluateAsAbsolute(Res, nullptr, nullptr, nullptr, false);
457 }
458 
459 bool MCExpr::evaluateAsAbsolute(int64_t &Res,
460  const MCAsmLayout &Layout) const {
461  return evaluateAsAbsolute(Res, &Layout.getAssembler(), &Layout, nullptr, false);
462 }
463 
464 bool MCExpr::evaluateAsAbsolute(int64_t &Res,
465  const MCAsmLayout &Layout,
466  const SectionAddrMap &Addrs) const {
467  // Setting InSet causes us to absolutize differences across sections and that
468  // is what the MachO writer uses Addrs for.
469  return evaluateAsAbsolute(Res, &Layout.getAssembler(), &Layout, &Addrs, true);
470 }
471 
472 bool MCExpr::evaluateAsAbsolute(int64_t &Res, const MCAssembler &Asm) const {
473  return evaluateAsAbsolute(Res, &Asm, nullptr, nullptr, false);
474 }
475 
476 bool MCExpr::evaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm) const {
477  return evaluateAsAbsolute(Res, Asm, nullptr, nullptr, false);
478 }
479 
480 bool MCExpr::evaluateKnownAbsolute(int64_t &Res,
481  const MCAsmLayout &Layout) const {
482  return evaluateAsAbsolute(Res, &Layout.getAssembler(), &Layout, nullptr,
483  true);
484 }
485 
486 bool MCExpr::evaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm,
487  const MCAsmLayout *Layout,
488  const SectionAddrMap *Addrs, bool InSet) const {
489  MCValue Value;
490 
491  // Fast path constants.
492  if (const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(this)) {
493  Res = CE->getValue();
494  return true;
495  }
496 
497  bool IsRelocatable =
498  evaluateAsRelocatableImpl(Value, Asm, Layout, nullptr, Addrs, InSet);
499 
500  // Record the current value.
501  Res = Value.getConstant();
502 
503  return IsRelocatable && Value.isAbsolute();
504 }
505 
506 /// Helper method for \see EvaluateSymbolAdd().
507 static void AttemptToFoldSymbolOffsetDifference(
508  const MCAssembler *Asm, const MCAsmLayout *Layout,
509  const SectionAddrMap *Addrs, bool InSet, const MCSymbolRefExpr *&A,
510  const MCSymbolRefExpr *&B, int64_t &Addend) {
511  if (!A || !B)
512  return;
513 
514  const MCSymbol &SA = A->getSymbol();
515  const MCSymbol &SB = B->getSymbol();
516 
517  if (SA.isUndefined() || SB.isUndefined())
518  return;
519 
520  if (!Asm->getWriter().isSymbolRefDifferenceFullyResolved(*Asm, A, B, InSet))
521  return;
522 
523  if (SA.getFragment() == SB.getFragment() && !SA.isVariable() &&
524  !SA.isUnset() && !SB.isVariable() && !SB.isUnset()) {
525  Addend += (SA.getOffset() - SB.getOffset());
526 
527  // Pointers to Thumb symbols need to have their low-bit set to allow
528  // for interworking.
529  if (Asm->isThumbFunc(&SA))
530  Addend |= 1;
531 
532  // If symbol is labeled as micromips, we set low-bit to ensure
533  // correct offset in .gcc_except_table
534  if (Asm->getBackend().isMicroMips(&SA))
535  Addend |= 1;
536 
537  // Clear the symbol expr pointers to indicate we have folded these
538  // operands.
539  A = B = nullptr;
540  return;
541  }
542 
543  if (!Layout)
544  return;
545 
546  const MCSection &SecA = *SA.getFragment()->getParent();
547  const MCSection &SecB = *SB.getFragment()->getParent();
548 
549  if ((&SecA != &SecB) && !Addrs)
550  return;
551 
552  // Eagerly evaluate.
553  Addend += Layout->getSymbolOffset(A->getSymbol()) -
554  Layout->getSymbolOffset(B->getSymbol());
555  if (Addrs && (&SecA != &SecB))
556  Addend += (Addrs->lookup(&SecA) - Addrs->lookup(&SecB));
557 
558  // Pointers to Thumb symbols need to have their low-bit set to allow
559  // for interworking.
560  if (Asm->isThumbFunc(&SA))
561  Addend |= 1;
562 
563  // If symbol is labeled as micromips, we set low-bit to ensure
564  // correct offset in .gcc_except_table
565  if (Asm->getBackend().isMicroMips(&SA))
566  Addend |= 1;
567 
568  // Clear the symbol expr pointers to indicate we have folded these
569  // operands.
570  A = B = nullptr;
571 }
572 
573 static bool canFold(const MCAssembler *Asm, const MCSymbolRefExpr *A,
574  const MCSymbolRefExpr *B, bool InSet) {
575  if (InSet)
576  return true;
577 
578  if (!Asm->getBackend().requiresDiffExpressionRelocations())
579  return true;
580 
581  const MCSymbol &CheckSym = A ? A->getSymbol() : B->getSymbol();
582  if (!CheckSym.isInSection())
583  return true;
584 
585  if (!CheckSym.getSection().hasInstructions())
586  return true;
587 
588  return false;
589 }
590 
591 /// Evaluate the result of an add between (conceptually) two MCValues.
592 ///
593 /// This routine conceptually attempts to construct an MCValue:
594 /// Result = (Result_A - Result_B + Result_Cst)
595 /// from two MCValue's LHS and RHS where
596 /// Result = LHS + RHS
597 /// and
598 /// Result = (LHS_A - LHS_B + LHS_Cst) + (RHS_A - RHS_B + RHS_Cst).
599 ///
600 /// This routine attempts to aggresively fold the operands such that the result
601 /// is representable in an MCValue, but may not always succeed.
602 ///
603 /// \returns True on success, false if the result is not representable in an
604 /// MCValue.
605 
606 /// NOTE: It is really important to have both the Asm and Layout arguments.
607 /// They might look redundant, but this function can be used before layout
608 /// is done (see the object streamer for example) and having the Asm argument
609 /// lets us avoid relaxations early.
610 static bool
611 EvaluateSymbolicAdd(const MCAssembler *Asm, const MCAsmLayout *Layout,
612  const SectionAddrMap *Addrs, bool InSet, const MCValue &LHS,
613  const MCSymbolRefExpr *RHS_A, const MCSymbolRefExpr *RHS_B,
614  int64_t RHS_Cst, MCValue &Res) {
615  // FIXME: This routine (and other evaluation parts) are *incredibly* sloppy
616  // about dealing with modifiers. This will ultimately bite us, one day.
617  const MCSymbolRefExpr *LHS_A = LHS.getSymA();
618  const MCSymbolRefExpr *LHS_B = LHS.getSymB();
619  int64_t LHS_Cst = LHS.getConstant();
620 
621  // Fold the result constant immediately.
622  int64_t Result_Cst = LHS_Cst + RHS_Cst;
623 
624  assert((!Layout || Asm) &&
625  "Must have an assembler object if layout is given!");
626 
627  // If we have a layout, we can fold resolved differences. Do not do this if
628  // the backend requires this to be emitted as individual relocations, unless
629  // the InSet flag is set to get the current difference anyway (used for
630  // example to calculate symbol sizes).
631  if (Asm && canFold(Asm, LHS_A, LHS_B, InSet)) {
632  // First, fold out any differences which are fully resolved. By
633  // reassociating terms in
634  // Result = (LHS_A - LHS_B + LHS_Cst) + (RHS_A - RHS_B + RHS_Cst).
635  // we have the four possible differences:
636  // (LHS_A - LHS_B),
637  // (LHS_A - RHS_B),
638  // (RHS_A - LHS_B),
639  // (RHS_A - RHS_B).
640  // Since we are attempting to be as aggressive as possible about folding, we
641  // attempt to evaluate each possible alternative.
642  AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, LHS_A, LHS_B,
643  Result_Cst);
644  AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, LHS_A, RHS_B,
645  Result_Cst);
646  AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, RHS_A, LHS_B,
647  Result_Cst);
648  AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, RHS_A, RHS_B,
649  Result_Cst);
650  }
651 
652  // We can't represent the addition or subtraction of two symbols.
653  if ((LHS_A && RHS_A) || (LHS_B && RHS_B))
654  return false;
655 
656  // At this point, we have at most one additive symbol and one subtractive
657  // symbol -- find them.
658  const MCSymbolRefExpr *A = LHS_A ? LHS_A : RHS_A;
659  const MCSymbolRefExpr *B = LHS_B ? LHS_B : RHS_B;
660 
661  Res = MCValue::get(A, B, Result_Cst);
662  return true;
663 }
664 
665 bool MCExpr::evaluateAsRelocatable(MCValue &Res,
666  const MCAsmLayout *Layout,
667  const MCFixup *Fixup) const {
668  MCAssembler *Assembler = Layout ? &Layout->getAssembler() : nullptr;
669  return evaluateAsRelocatableImpl(Res, Assembler, Layout, Fixup, nullptr,
670  false);
671 }
672 
673 bool MCExpr::evaluateAsValue(MCValue &Res, const MCAsmLayout &Layout) const {
674  MCAssembler *Assembler = &Layout.getAssembler();
675  return evaluateAsRelocatableImpl(Res, Assembler, &Layout, nullptr, nullptr,
676  true);
677 }
678 
679 static bool canExpand(const MCSymbol &Sym, bool InSet) {
680  const MCExpr *Expr = Sym.getVariableValue();
681  const auto *Inner = dyn_cast<MCSymbolRefExpr>(Expr);
682  if (Inner) {
683  if (Inner->getKind() == MCSymbolRefExpr::VK_WEAKREF)
684  return false;
685  }
686 
687  if (InSet)
688  return true;
689  return !Sym.isInSection();
690 }
691 
692 bool MCExpr::evaluateAsRelocatableImpl(MCValue &Res, const MCAssembler *Asm,
693  const MCAsmLayout *Layout,
694  const MCFixup *Fixup,
695  const SectionAddrMap *Addrs,
696  bool InSet) const {
697  ++stats::MCExprEvaluate;
698 
699  switch (getKind()) {
700  case Target:
701  return cast<MCTargetExpr>(this)->evaluateAsRelocatableImpl(Res, Layout,
702  Fixup);
703 
704  case Constant:
705  Res = MCValue::get(cast<MCConstantExpr>(this)->getValue());
706  return true;
707 
708  case SymbolRef: {
709  const MCSymbolRefExpr *SRE = cast<MCSymbolRefExpr>(this);
710  const MCSymbol &Sym = SRE->getSymbol();
711 
712  // Evaluate recursively if this is a variable.
713  if (Sym.isVariable() && SRE->getKind() == MCSymbolRefExpr::VK_None &&
714  canExpand(Sym, InSet)) {
715  bool IsMachO = SRE->hasSubsectionsViaSymbols();
716  if (Sym.getVariableValue()->evaluateAsRelocatableImpl(
717  Res, Asm, Layout, Fixup, Addrs, InSet || IsMachO)) {
718  if (!IsMachO)
719  return true;
720 
721  const MCSymbolRefExpr *A = Res.getSymA();
722  const MCSymbolRefExpr *B = Res.getSymB();
723  // FIXME: This is small hack. Given
724  // a = b + 4
725  // .long a
726  // the OS X assembler will completely drop the 4. We should probably
727  // include it in the relocation or produce an error if that is not
728  // possible.
729  // Allow constant expressions.
730  if (!A && !B)
731  return true;
732  // Allows aliases with zero offset.
733  if (Res.getConstant() == 0 && (!A || !B))
734  return true;
735  }
736  }
737 
738  Res = MCValue::get(SRE, nullptr, 0);
739  return true;
740  }
741 
742  case Unary: {
743  const MCUnaryExpr *AUE = cast<MCUnaryExpr>(this);
744  MCValue Value;
745 
746  if (!AUE->getSubExpr()->evaluateAsRelocatableImpl(Value, Asm, Layout, Fixup,
747  Addrs, InSet))
748  return false;
749 
750  switch (AUE->getOpcode()) {
751  case MCUnaryExpr::LNot:
752  if (!Value.isAbsolute())
753  return false;
754  Res = MCValue::get(!Value.getConstant());
755  break;
756  case MCUnaryExpr::Minus:
757  /// -(a - b + const) ==> (b - a - const)
758  if (Value.getSymA() && !Value.getSymB())
759  return false;
760 
761  // The cast avoids undefined behavior if the constant is INT64_MIN.
762  Res = MCValue::get(Value.getSymB(), Value.getSymA(),
763  -(uint64_t)Value.getConstant());
764  break;
765  case MCUnaryExpr::Not:
766  if (!Value.isAbsolute())
767  return false;
768  Res = MCValue::get(~Value.getConstant());
769  break;
770  case MCUnaryExpr::Plus:
771  Res = Value;
772  break;
773  }
774 
775  return true;
776  }
777 
778  case Binary: {
779  const MCBinaryExpr *ABE = cast<MCBinaryExpr>(this);
780  MCValue LHSValue, RHSValue;
781 
782  if (!ABE->getLHS()->evaluateAsRelocatableImpl(LHSValue, Asm, Layout, Fixup,
783  Addrs, InSet) ||
784  !ABE->getRHS()->evaluateAsRelocatableImpl(RHSValue, Asm, Layout, Fixup,
785  Addrs, InSet)) {
786  // Check if both are Target Expressions, see if we can compare them.
787  if (const MCTargetExpr *L = dyn_cast<MCTargetExpr>(ABE->getLHS()))
788  if (const MCTargetExpr *R = cast<MCTargetExpr>(ABE->getRHS())) {
789  switch (ABE->getOpcode()) {
790  case MCBinaryExpr::EQ:
791  Res = MCValue::get((L->isEqualTo(R)) ? -1 : 0);
792  return true;
793  case MCBinaryExpr::NE:
794  Res = MCValue::get((R->isEqualTo(R)) ? 0 : -1);
795  return true;
796  default: break;
797  }
798  }
799  return false;
800  }
801 
802  // We only support a few operations on non-constant expressions, handle
803  // those first.
804  if (!LHSValue.isAbsolute() || !RHSValue.isAbsolute()) {
805  switch (ABE->getOpcode()) {
806  default:
807  return false;
808  case MCBinaryExpr::Sub:
809  // Negate RHS and add.
810  // The cast avoids undefined behavior if the constant is INT64_MIN.
811  return EvaluateSymbolicAdd(Asm, Layout, Addrs, InSet, LHSValue,
812  RHSValue.getSymB(), RHSValue.getSymA(),
813  -(uint64_t)RHSValue.getConstant(), Res);
814 
815  case MCBinaryExpr::Add:
816  return EvaluateSymbolicAdd(Asm, Layout, Addrs, InSet, LHSValue,
817  RHSValue.getSymA(), RHSValue.getSymB(),
818  RHSValue.getConstant(), Res);
819  }
820  }
821 
822  // FIXME: We need target hooks for the evaluation. It may be limited in
823  // width, and gas defines the result of comparisons differently from
824  // Apple as.
825  int64_t LHS = LHSValue.getConstant(), RHS = RHSValue.getConstant();
826  int64_t Result = 0;
827  auto Op = ABE->getOpcode();
828  switch (Op) {
829  case MCBinaryExpr::AShr: Result = LHS >> RHS; break;
830  case MCBinaryExpr::Add: Result = LHS + RHS; break;
831  case MCBinaryExpr::And: Result = LHS & RHS; break;
832  case MCBinaryExpr::Div:
833  case MCBinaryExpr::Mod:
834  // Handle division by zero. gas just emits a warning and keeps going,
835  // we try to be stricter.
836  // FIXME: Currently the caller of this function has no way to understand
837  // we're bailing out because of 'division by zero'. Therefore, it will
838  // emit a 'expected relocatable expression' error. It would be nice to
839  // change this code to emit a better diagnostic.
840  if (RHS == 0)
841  return false;
842  if (ABE->getOpcode() == MCBinaryExpr::Div)
843  Result = LHS / RHS;
844  else
845  Result = LHS % RHS;
846  break;
847  case MCBinaryExpr::EQ: Result = LHS == RHS; break;
848  case MCBinaryExpr::GT: Result = LHS > RHS; break;
849  case MCBinaryExpr::GTE: Result = LHS >= RHS; break;
850  case MCBinaryExpr::LAnd: Result = LHS && RHS; break;
851  case MCBinaryExpr::LOr: Result = LHS || RHS; break;
852  case MCBinaryExpr::LShr: Result = uint64_t(LHS) >> uint64_t(RHS); break;
853  case MCBinaryExpr::LT: Result = LHS < RHS; break;
854  case MCBinaryExpr::LTE: Result = LHS <= RHS; break;
855  case MCBinaryExpr::Mul: Result = LHS * RHS; break;
856  case MCBinaryExpr::NE: Result = LHS != RHS; break;
857  case MCBinaryExpr::Or: Result = LHS | RHS; break;
858  case MCBinaryExpr::Shl: Result = uint64_t(LHS) << uint64_t(RHS); break;
859  case MCBinaryExpr::Sub: Result = LHS - RHS; break;
860  case MCBinaryExpr::Xor: Result = LHS ^ RHS; break;
861  }
862 
863  switch (Op) {
864  default:
865  Res = MCValue::get(Result);
866  break;
867  case MCBinaryExpr::EQ:
868  case MCBinaryExpr::GT:
869  case MCBinaryExpr::GTE:
870  case MCBinaryExpr::LT:
871  case MCBinaryExpr::LTE:
872  case MCBinaryExpr::NE:
873  // A comparison operator returns a -1 if true and 0 if false.
874  Res = MCValue::get(Result ? -1 : 0);
875  break;
876  }
877 
878  return true;
879  }
880  }
881 
882  llvm_unreachable("Invalid assembly expression kind!");
883 }
884 
885 MCFragment *MCExpr::findAssociatedFragment() const {
886  switch (getKind()) {
887  case Target:
888  // We never look through target specific expressions.
889  return cast<MCTargetExpr>(this)->findAssociatedFragment();
890 
891  case Constant:
892  return MCSymbol::AbsolutePseudoFragment;
893 
894  case SymbolRef: {
895  const MCSymbolRefExpr *SRE = cast<MCSymbolRefExpr>(this);
896  const MCSymbol &Sym = SRE->getSymbol();
897  return Sym.getFragment();
898  }
899 
900  case Unary:
901  return cast<MCUnaryExpr>(this)->getSubExpr()->findAssociatedFragment();
902 
903  case Binary: {
904  const MCBinaryExpr *BE = cast<MCBinaryExpr>(this);
905  MCFragment *LHS_F = BE->getLHS()->findAssociatedFragment();
906  MCFragment *RHS_F = BE->getRHS()->findAssociatedFragment();
907 
908  // If either is absolute, return the other.
909  if (LHS_F == MCSymbol::AbsolutePseudoFragment)
910  return RHS_F;
911  if (RHS_F == MCSymbol::AbsolutePseudoFragment)
912  return LHS_F;
913 
914  // Not always correct, but probably the best we can do without more context.
915  if (BE->getOpcode() == MCBinaryExpr::Sub)
916  return MCSymbol::AbsolutePseudoFragment;
917 
918  // Otherwise, return the first non-null fragment.
919  return LHS_F ? LHS_F : RHS_F;
920  }
921  }
922 
923  llvm_unreachable("Invalid assembly expression kind!");
924 }
llvm::MCBinaryExpr::LT
Signed less than comparison (result is either 0 or some target-specific non-zero value).
Definition: MCExpr.h:434
llvm::MCUnaryExpr::Not
Bitwise negation.
Definition: MCExpr.h:369
llvm
This class represents lattice values for constants.
Definition: AllocatorList.h:23
llvm::MCBinaryExpr::LTE
Signed less than or equal comparison (result is either 0 or some target-specific non-zero value)...
Definition: MCExpr.h:436
llvm::MCValue
This represents an "assembler immediate".
Definition: MCValue.h:39
llvm::MCSymbol
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:41
llvm::MCSymbolRefExpr::getKind
VariantKind getKind() const
Definition: MCExpr.h:342
llvm::MCBinaryExpr::And
Bitwise and.
Definition: MCExpr.h:425
llvm::MCBinaryExpr::Mul
Multiplication.
Definition: MCExpr.h:439
llvm::MCUnaryExpr::getOpcode
Opcode getOpcode() const
Get the kind of this unary expression.
Definition: MCExpr.h:408
llvm::MCBinaryExpr::getLHS
const MCExpr * getLHS() const
Get the left-hand side expression of the binary operator.
Definition: MCExpr.h:568
llvm::MCUnaryExpr::Plus
Unary plus.
Definition: MCExpr.h:370
llvm::STATISTIC
STATISTIC(NumFunctions, "Total number of functions")
llvm::MCBinaryExpr::EQ
Equality comparison.
Definition: MCExpr.h:427
llvm::MCBinaryExpr::Or
Bitwise or.
Definition: MCExpr.h:441
llvm::MCFixup
Encode information on a single operation to perform on a byte sequence (e.g., an encoded instruction)...
Definition: MCFixup.h:77
llvm::MCValue::getConstant
int64_t getConstant() const
Definition: MCValue.h:46
llvm::MCValue::getSymB
const MCSymbolRefExpr * getSymB() const
Definition: MCValue.h:48
llvm::MCAsmLayout
Encapsulates the layout of an assembly file at a particular point in time.
Definition: MCAsmLayout.h:28
llvm::MCExpr
Base class for the full range of assembler expressions which are needed for parsing.
Definition: MCExpr.h:35
llvm::MCTargetExpr
This is an extension point for target-specific MCExpr subclasses to implement.
Definition: MCExpr.h:585
llvm::MCSymbol::isInSection
bool isInSection() const
isInSection - Check if this symbol is defined in some section (i.e., it is defined but not absolute)...
Definition: MCSymbol.h:253
llvm::MCSymbolRefExpr
Represent a reference to a symbol from inside an expression.
Definition: MCExpr.h:169
llvm::StringRef::empty
LLVM_NODISCARD bool empty() const
empty - Check if the string is empty.
Definition: StringRef.h:140
llvm::MCBinaryExpr::AShr
Arithmetic shift right.
Definition: MCExpr.h:443
llvm::MCExpr::evaluateAsRelocatable
bool evaluateAsRelocatable(MCValue &Res, const MCAsmLayout *Layout, const MCFixup *Fixup) const
Try to evaluate the expression to a relocatable value, i.e.
Definition: MCExpr.cpp:665
llvm::MCBinaryExpr::getRHS
const MCExpr * getRHS() const
Get the right-hand side expression of the binary operator.
Definition: MCExpr.h:571
llvm::MCBinaryExpr::LOr
Logical or.
Definition: MCExpr.h:433
llvm::MCBinaryExpr::Mod
Signed remainder.
Definition: MCExpr.h:438
llvm::MCUnaryExpr
Unary assembler expressions.
Definition: MCExpr.h:364
canExpand
static bool canExpand(const MCSymbol &Sym, bool InSet)
Definition: MCExpr.cpp:679
llvm::MCBinaryExpr::Div
Signed division.
Definition: MCExpr.h:426
llvm::MCAsmLayout::getAssembler
MCAssembler & getAssembler() const
Get the assembler object this is a layout for.
Definition: MCAsmLayout.h:50
llvm::MCExpr::Unary
Unary expressions.
Definition: MCExpr.h:41
llvm::MCBinaryExpr::Shl
Shift left.
Definition: MCExpr.h:442
llvm::MCAsmInfo
This class is intended to be used as a base class for asm properties and features specific to the tar...
Definition: MCAsmInfo.h:56
B
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
llvm::MCExpr::print
void print(raw_ostream &OS, const MCAsmInfo *MAI, bool InParens=false) const
Definition: MCExpr.cpp:42
llvm::Constant
This is an important base class in LLVM.
Definition: Constant.h:41
EvaluateSymbolicAdd
static bool EvaluateSymbolicAdd(const MCAssembler *Asm, const MCAsmLayout *Layout, const SectionAddrMap *Addrs, bool InSet, const MCValue &LHS, const MCSymbolRefExpr *RHS_A, const MCSymbolRefExpr *RHS_B, int64_t RHS_Cst, MCValue &Res)
Evaluate the result of an add between (conceptually) two MCValues.
Definition: MCExpr.cpp:611
llvm::MCValue::getSymA
const MCSymbolRefExpr * getSymA() const
Definition: MCValue.h:47
llvm::MCUnaryExpr::LNot
Logical negation.
Definition: MCExpr.h:367
llvm::MCBinaryExpr::LAnd
Logical and.
Definition: MCExpr.h:432
llvm::MCBinaryExpr
Binary assembler expressions.
Definition: MCExpr.h:421
llvm::MCSymbolRefExpr::hasSubsectionsViaSymbols
bool hasSubsectionsViaSymbols() const
Definition: MCExpr.h:346
llvm_unreachable
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
Definition: ErrorHandling.h:135
llvm::MCSymbol::AbsolutePseudoFragment
static MCFragment * AbsolutePseudoFragment
Definition: MCSymbol.h:65
llvm::MCSymbolRefExpr::printVariantKind
void printVariantKind(raw_ostream &OS) const
Definition: MCExpr.cpp:442
llvm::MCSymbolRefExpr::getSymbol
const MCSymbol & getSymbol() const
Definition: MCExpr.h:340
llvm::MCExpr::getKind
ExprKind getKind() const
Definition: MCExpr.h:68
llvm::MCSymbol::getFragment
MCFragment * getFragment(bool SetUsed=true) const
Definition: MCSymbol.h:396
llvm::MCExpr::evaluateAsRelocatableImpl
bool evaluateAsRelocatableImpl(MCValue &Res, const MCAssembler *Asm, const MCAsmLayout *Layout, const MCFixup *Fixup, const SectionAddrMap *Addrs, bool InSet) const
Definition: MCExpr.cpp:692
llvm::MCBinaryExpr::NE
Inequality comparison.
Definition: MCExpr.h:440
llvm::Twine::utohexstr
static Twine utohexstr(const uint64_t &Val)
Definition: Twine.h:387
llvm::MCBinaryExpr::GT
Signed greater than comparison (result is either 0 or some target-specific non-zero value) ...
Definition: MCExpr.h:428
llvm::MCExpr::findAssociatedFragment
MCFragment * findAssociatedFragment() const
Find the "associated section" for this expression, which is currently defined as the absolute section...
Definition: MCExpr.cpp:885
llvm::MCBinaryExpr::GTE
Signed greater than or equal comparison (result is either 0 or some target-specific non-zero value)...
Definition: MCExpr.h:430
llvm::Target
Target - Wrapper for Target specific information.
Definition: TargetRegistry.h:124
llvm::MCBinaryExpr::Xor
Bitwise exclusive or.
Definition: MCExpr.h:446
llvm::MCBinaryExpr::LShr
Logical shift right.
Definition: MCExpr.h:444
llvm::MCValue::get
static MCValue get(const MCSymbolRefExpr *SymA, const MCSymbolRefExpr *SymB=nullptr, int64_t Val=0, uint32_t RefKind=0)
Definition: MCValue.h:62
llvm::dyn_cast
LLVM_NODISCARD std::enable_if<!is_simple_type< Y >::value, typename cast_retty< X, const Y >::ret_type >::type dyn_cast(const Y &Val)
Definition: Casting.h:332
llvm::MCExpr::SymbolRef
References to labels and assigned expressions.
Definition: MCExpr.h:40
llvm::MCUnaryExpr::Minus
Unary minus.
Definition: MCExpr.h:368
llvm::MCExpr::evaluateAsValue
bool evaluateAsValue(MCValue &Res, const MCAsmLayout &Layout) const
Try to evaluate the expression to the form (a - b + constant) where neither a nor b are variables...
Definition: MCExpr.cpp:673
llvm::MCBinaryExpr::getOpcode
Opcode getOpcode() const
Get the kind of this binary expression.
Definition: MCExpr.h:565
llvm::MCSymbol::getName
StringRef getName() const
getName - Get the symbol name.
Definition: MCSymbol.h:204
llvm::MCSymbol::getVariableValue
const MCExpr * getVariableValue(bool SetUsed=true) const
getVariableValue - Get the value for variable symbols.
Definition: MCSymbol.h:302
llvm::MCUnaryExpr::getSubExpr
const MCExpr * getSubExpr() const
Get the child of this unary expression.
Definition: MCExpr.h:411
llvm::Value
LLVM Value Representation.
Definition: Value.h:73
llvm::MCExpr::Constant
Constant expressions.
Definition: MCExpr.h:39
llvm::MCExpr::Binary
Binary expressions.
Definition: MCExpr.h:38
llvm::raw_ostream
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:45
llvm::MCBinaryExpr::Sub
Subtraction.
Definition: MCExpr.h:445
raw_ostream.h
llvm::MCExpr::Target
Target specific expression.
Definition: MCExpr.h:42
llvm::MCSymbol::print
void print(raw_ostream &OS, const MCAsmInfo *MAI) const
print - Print the value to the stream OS.
Definition: MCSymbol.cpp:59
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