1//===- llvm/BasicBlock.h - Represent a basic block in the VM ----*- C++ -*-===//
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// This file contains the declaration of the BasicBlock class.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_IR_BASICBLOCK_H
14#define LLVM_IR_BASICBLOCK_H
15
16#include "llvm-c/Types.h"
17#include "llvm/ADT/Twine.h"
18#include "llvm/ADT/ilist.h"
19#include "llvm/ADT/ilist_node.h"
20#include "llvm/ADT/iterator.h"
21#include "llvm/ADT/iterator_range.h"
22#include "llvm/IR/Instruction.h"
23#include "llvm/IR/SymbolTableListTraits.h"
24#include "llvm/IR/Value.h"
25#include "llvm/Support/CBindingWrapping.h"
26#include "llvm/Support/Casting.h"
27#include "llvm/Support/Compiler.h"
28#include <cassert>
29#include <cstddef>
30#include <iterator>
31
32namespace llvm {
33
34class AssemblyAnnotationWriter;
35class CallInst;
36class Function;
37class LandingPadInst;
38class LLVMContext;
39class Module;
40class PHINode;
41class ValueSymbolTable;
42
43/// LLVM Basic Block Representation
44///
45/// This represents a single basic block in LLVM. A basic block is simply a
46/// container of instructions that execute sequentially. Basic blocks are Values
47/// because they are referenced by instructions such as branches and switch
48/// tables. The type of a BasicBlock is "Type::LabelTy" because the basic block
49/// represents a label to which a branch can jump.
50///
51/// A well formed basic block is formed of a list of non-terminating
52/// instructions followed by a single terminator instruction. Terminator
53/// instructions may not occur in the middle of basic blocks, and must terminate
54/// the blocks. The BasicBlock class allows malformed basic blocks to occur
55/// because it may be useful in the intermediate stage of constructing or
56/// modifying a program. However, the verifier will ensure that basic blocks are
57/// "well formed".
58class BasicBlock final : public Value, // Basic blocks are data objects also
59 public ilist_node_with_parent<BasicBlock, Function> {
60public:
61 using InstListType = SymbolTableList<Instruction>;
62
63private:
64 friend class BlockAddress;
65 friend class SymbolTableListTraits<BasicBlock>;
66
67 InstListType InstList;
68 Function *Parent;
69
70 void setParent(Function *parent);
71
72 /// Constructor.
73 ///
74 /// If the function parameter is specified, the basic block is automatically
75 /// inserted at either the end of the function (if InsertBefore is null), or
76 /// before the specified basic block.
77 explicit BasicBlock(LLVMContext &C, const Twine &Name = "",
78 Function *Parent = nullptr,
79 BasicBlock *InsertBefore = nullptr);
80
81public:
82 BasicBlock(const BasicBlock &) = delete;
83 BasicBlock &operator=(const BasicBlock &) = delete;
84 ~BasicBlock();
85
86 /// Get the context in which this basic block lives.
87 LLVMContext &getContext() const;
88
89 /// Instruction iterators...
90 using iterator = InstListType::iterator;
91 using const_iterator = InstListType::const_iterator;
92 using reverse_iterator = InstListType::reverse_iterator;
93 using const_reverse_iterator = InstListType::const_reverse_iterator;
94
95 /// Creates a new BasicBlock.
96 ///
97 /// If the Parent parameter is specified, the basic block is automatically
98 /// inserted at either the end of the function (if InsertBefore is 0), or
99 /// before the specified basic block.
100 static BasicBlock *Create(LLVMContext &Context, const Twine &Name = "",
101 Function *Parent = nullptr,
102 BasicBlock *InsertBefore = nullptr) {
103 return new BasicBlock(Context, Name, Parent, InsertBefore);
104 }
105
106 /// Return the enclosing method, or null if none.
107 const Function *getParent() const { return Parent; }
108 Function *getParent() { return Parent; }
109
110 /// Return the module owning the function this basic block belongs to, or
111 /// nullptr if the function does not have a module.
112 ///
113 /// Note: this is undefined behavior if the block does not have a parent.
114 const Module *getModule() const;
115 Module *getModule() {
116 return const_cast<Module *>(
117 static_cast<const BasicBlock *>(this)->getModule());
118 }
119
120 /// Returns the terminator instruction if the block is well formed or null
121 /// if the block is not well formed.
122 const Instruction *getTerminator() const LLVM_READONLY;
123 Instruction *getTerminator() {
124 return const_cast<Instruction *>(
125 static_cast<const BasicBlock *>(this)->getTerminator());
126 }
127
128 /// Returns the call instruction calling \@llvm.experimental.deoptimize
129 /// prior to the terminating return instruction of this basic block, if such
130 /// a call is present. Otherwise, returns null.
131 const CallInst *getTerminatingDeoptimizeCall() const;
132 CallInst *getTerminatingDeoptimizeCall() {
133 return const_cast<CallInst *>(
134 static_cast<const BasicBlock *>(this)->getTerminatingDeoptimizeCall());
135 }
136
137 /// Returns the call instruction calling \@llvm.experimental.deoptimize
138 /// that is present either in current basic block or in block that is a unique
139 /// successor to current block, if such call is present. Otherwise, returns null.
140 const CallInst *getPostdominatingDeoptimizeCall() const;
141 CallInst *getPostdominatingDeoptimizeCall() {
142 return const_cast<CallInst *>(
143 static_cast<const BasicBlock *>(this)->getPostdominatingDeoptimizeCall());
144 }
145
146 /// Returns the call instruction marked 'musttail' prior to the terminating
147 /// return instruction of this basic block, if such a call is present.
148 /// Otherwise, returns null.
149 const CallInst *getTerminatingMustTailCall() const;
150 CallInst *getTerminatingMustTailCall() {
151 return const_cast<CallInst *>(
152 static_cast<const BasicBlock *>(this)->getTerminatingMustTailCall());
153 }
154
155 /// Returns a pointer to the first instruction in this block that is not a
156 /// PHINode instruction.
157 ///
158 /// When adding instructions to the beginning of the basic block, they should
159 /// be added before the returned value, not before the first instruction,
160 /// which might be PHI. Returns 0 is there's no non-PHI instruction.
161 const Instruction* getFirstNonPHI() const;
162 Instruction* getFirstNonPHI() {
163 return const_cast<Instruction *>(
164 static_cast<const BasicBlock *>(this)->getFirstNonPHI());
165 }
166
167 /// Returns a pointer to the first instruction in this block that is not a
168 /// PHINode or a debug intrinsic, or any pseudo operation if \c SkipPseudoOp
169 /// is true.
170 const Instruction *getFirstNonPHIOrDbg(bool SkipPseudoOp = false) const;
171 Instruction *getFirstNonPHIOrDbg(bool SkipPseudoOp = false) {
172 return const_cast<Instruction *>(
173 static_cast<const BasicBlock *>(this)->getFirstNonPHIOrDbg(
174 SkipPseudoOp));
175 }
176
177 /// Returns a pointer to the first instruction in this block that is not a
178 /// PHINode, a debug intrinsic, or a lifetime intrinsic, or any pseudo
179 /// operation if \c SkipPseudoOp is true.
180 const Instruction *
181 getFirstNonPHIOrDbgOrLifetime(bool SkipPseudoOp = false) const;
182 Instruction *getFirstNonPHIOrDbgOrLifetime(bool SkipPseudoOp = false) {
183 return const_cast<Instruction *>(
184 static_cast<const BasicBlock *>(this)->getFirstNonPHIOrDbgOrLifetime(
185 SkipPseudoOp));
186 }
187
188 /// Returns an iterator to the first instruction in this block that is
189 /// suitable for inserting a non-PHI instruction.
190 ///
191 /// In particular, it skips all PHIs and LandingPad instructions.
192 const_iterator getFirstInsertionPt() const;
193 iterator getFirstInsertionPt() {
194 return static_cast<const BasicBlock *>(this)
195 ->getFirstInsertionPt().getNonConst();
196 }
197
198 /// Return a const iterator range over the instructions in the block, skipping
199 /// any debug instructions. Skip any pseudo operations as well if \c
200 /// SkipPseudoOp is true.
201 iterator_range<filter_iterator<BasicBlock::const_iterator,
202 std::function<bool(const Instruction &)>>>
203 instructionsWithoutDebug(bool SkipPseudoOp = false) const;
204
205 /// Return an iterator range over the instructions in the block, skipping any
206 /// debug instructions. Skip and any pseudo operations as well if \c
207 /// SkipPseudoOp is true.
208 iterator_range<
209 filter_iterator<BasicBlock::iterator, std::function<bool(Instruction &)>>>
210 instructionsWithoutDebug(bool SkipPseudoOp = false);
211
212 /// Return the size of the basic block ignoring debug instructions
213 filter_iterator<BasicBlock::const_iterator,
214 std::function<bool(const Instruction &)>>::difference_type
215 sizeWithoutDebug() const;
216
217 /// Unlink 'this' from the containing function, but do not delete it.
218 void removeFromParent();
219
220 /// Unlink 'this' from the containing function and delete it.
221 ///
222 // \returns an iterator pointing to the element after the erased one.
223 SymbolTableList<BasicBlock>::iterator eraseFromParent();
224
225 /// Unlink this basic block from its current function and insert it into
226 /// the function that \p MovePos lives in, right before \p MovePos.
227 void moveBefore(BasicBlock *MovePos);
228
229 /// Unlink this basic block from its current function and insert it
230 /// right after \p MovePos in the function \p MovePos lives in.
231 void moveAfter(BasicBlock *MovePos);
232
233 /// Insert unlinked basic block into a function.
234 ///
235 /// Inserts an unlinked basic block into \c Parent. If \c InsertBefore is
236 /// provided, inserts before that basic block, otherwise inserts at the end.
237 ///
238 /// \pre \a getParent() is \c nullptr.
239 void insertInto(Function *Parent, BasicBlock *InsertBefore = nullptr);
240
241 /// Return the predecessor of this block if it has a single predecessor
242 /// block. Otherwise return a null pointer.
243 const BasicBlock *getSinglePredecessor() const;
244 BasicBlock *getSinglePredecessor() {
245 return const_cast<BasicBlock *>(
246 static_cast<const BasicBlock *>(this)->getSinglePredecessor());
247 }
248
249 /// Return the predecessor of this block if it has a unique predecessor
250 /// block. Otherwise return a null pointer.
251 ///
252 /// Note that unique predecessor doesn't mean single edge, there can be
253 /// multiple edges from the unique predecessor to this block (for example a
254 /// switch statement with multiple cases having the same destination).
255 const BasicBlock *getUniquePredecessor() const;
256 BasicBlock *getUniquePredecessor() {
257 return const_cast<BasicBlock *>(
258 static_cast<const BasicBlock *>(this)->getUniquePredecessor());
259 }
260
261 /// Return true if this block has exactly N predecessors.
262 bool hasNPredecessors(unsigned N) const;
263
264 /// Return true if this block has N predecessors or more.
265 bool hasNPredecessorsOrMore(unsigned N) const;
266
267 /// Return the successor of this block if it has a single successor.
268 /// Otherwise return a null pointer.
269 ///
270 /// This method is analogous to getSinglePredecessor above.
271 const BasicBlock *getSingleSuccessor() const;
272 BasicBlock *getSingleSuccessor() {
273 return const_cast<BasicBlock *>(
274 static_cast<const BasicBlock *>(this)->getSingleSuccessor());
275 }
276
277 /// Return the successor of this block if it has a unique successor.
278 /// Otherwise return a null pointer.
279 ///
280 /// This method is analogous to getUniquePredecessor above.
281 const BasicBlock *getUniqueSuccessor() const;
282 BasicBlock *getUniqueSuccessor() {
283 return const_cast<BasicBlock *>(
284 static_cast<const BasicBlock *>(this)->getUniqueSuccessor());
285 }
286
287 /// Print the basic block to an output stream with an optional
288 /// AssemblyAnnotationWriter.
289 void print(raw_ostream &OS, AssemblyAnnotationWriter *AAW = nullptr,
290 bool ShouldPreserveUseListOrder = false,
291 bool IsForDebug = false) const;
292
293 //===--------------------------------------------------------------------===//
294 /// Instruction iterator methods
295 ///
296 inline iterator begin() { return InstList.begin(); }
297 inline const_iterator begin() const { return InstList.begin(); }
298 inline iterator end () { return InstList.end(); }
299 inline const_iterator end () const { return InstList.end(); }
300
301 inline reverse_iterator rbegin() { return InstList.rbegin(); }
302 inline const_reverse_iterator rbegin() const { return InstList.rbegin(); }
303 inline reverse_iterator rend () { return InstList.rend(); }
304 inline const_reverse_iterator rend () const { return InstList.rend(); }
305
306 inline size_t size() const { return InstList.size(); }
307 inline bool empty() const { return InstList.empty(); }
308 inline const Instruction &front() const { return InstList.front(); }
309 inline Instruction &front() { return InstList.front(); }
310 inline const Instruction &back() const { return InstList.back(); }
311 inline Instruction &back() { return InstList.back(); }
312
313 /// Iterator to walk just the phi nodes in the basic block.
314 template <typename PHINodeT = PHINode, typename BBIteratorT = iterator>
315 class phi_iterator_impl
316 : public iterator_facade_base<phi_iterator_impl<PHINodeT, BBIteratorT>,
317 std::forward_iterator_tag, PHINodeT> {
318 friend BasicBlock;
319
320 PHINodeT *PN;
321
322 phi_iterator_impl(PHINodeT *PN) : PN(PN) {}
323
324 public:
325 // Allow default construction to build variables, but this doesn't build
326 // a useful iterator.
327 phi_iterator_impl() = default;
328
329 // Allow conversion between instantiations where valid.
330 template <typename PHINodeU, typename BBIteratorU,
331 typename = std::enable_if_t<
332 std::is_convertible<PHINodeU *, PHINodeT *>::value>>
333 phi_iterator_impl(const phi_iterator_impl<PHINodeU, BBIteratorU> &Arg)
334 : PN(Arg.PN) {}
335
336 bool operator==(const phi_iterator_impl &Arg) const { return PN == Arg.PN; }
337
338 PHINodeT &operator*() const { return *PN; }
339
340 using phi_iterator_impl::iterator_facade_base::operator++;
341 phi_iterator_impl &operator++() {
342 assert(PN && "Cannot increment the end iterator!");
343 PN = dyn_cast<PHINodeT>(std::next(BBIteratorT(PN)));
344 return *this;
345 }
346 };
347 using phi_iterator = phi_iterator_impl<>;
348 using const_phi_iterator =
349 phi_iterator_impl<const PHINode, BasicBlock::const_iterator>;
350
351 /// Returns a range that iterates over the phis in the basic block.
352 ///
353 /// Note that this cannot be used with basic blocks that have no terminator.
354 iterator_range<const_phi_iterator> phis() const {
355 return const_cast<BasicBlock *>(this)->phis();
356 }
357 iterator_range<phi_iterator> phis();
358
359 /// Return the underlying instruction list container.
360 ///
361 /// Currently you need to access the underlying instruction list container
362 /// directly if you want to modify it.
363 const InstListType &getInstList() const { return InstList; }
364 InstListType &getInstList() { return InstList; }
365
366 /// Returns a pointer to a member of the instruction list.
367 static InstListType BasicBlock::*getSublistAccess(Instruction*) {
368 return &BasicBlock::InstList;
369 }
370
371 /// Returns a pointer to the symbol table if one exists.
372 ValueSymbolTable *getValueSymbolTable();
373
374 /// Methods for support type inquiry through isa, cast, and dyn_cast.
375 static bool classof(const Value *V) {
376 return V->getValueID() == Value::BasicBlockVal;
377 }
378
379 /// Cause all subinstructions to "let go" of all the references that said
380 /// subinstructions are maintaining.
381 ///
382 /// This allows one to 'delete' a whole class at a time, even though there may
383 /// be circular references... first all references are dropped, and all use
384 /// counts go to zero. Then everything is delete'd for real. Note that no
385 /// operations are valid on an object that has "dropped all references",
386 /// except operator delete.
387 void dropAllReferences();
388
389 /// Update PHI nodes in this BasicBlock before removal of predecessor \p Pred.
390 /// Note that this function does not actually remove the predecessor.
391 ///
392 /// If \p KeepOneInputPHIs is true then don't remove PHIs that are left with
393 /// zero or one incoming values, and don't simplify PHIs with all incoming
394 /// values the same.
395 void removePredecessor(BasicBlock *Pred, bool KeepOneInputPHIs = false);
396
397 bool canSplitPredecessors() const;
398
399 /// Split the basic block into two basic blocks at the specified instruction.
400 ///
401 /// If \p Before is true, splitBasicBlockBefore handles the
402 /// block splitting. Otherwise, execution proceeds as described below.
403 ///
404 /// Note that all instructions BEFORE the specified iterator
405 /// stay as part of the original basic block, an unconditional branch is added
406 /// to the original BB, and the rest of the instructions in the BB are moved
407 /// to the new BB, including the old terminator. The newly formed basic block
408 /// is returned. This function invalidates the specified iterator.
409 ///
410 /// Note that this only works on well formed basic blocks (must have a
411 /// terminator), and \p 'I' must not be the end of instruction list (which
412 /// would cause a degenerate basic block to be formed, having a terminator
413 /// inside of the basic block).
414 ///
415 /// Also note that this doesn't preserve any passes. To split blocks while
416 /// keeping loop information consistent, use the SplitBlock utility function.
417 BasicBlock *splitBasicBlock(iterator I, const Twine &BBName = "",
418 bool Before = false);
419 BasicBlock *splitBasicBlock(Instruction *I, const Twine &BBName = "",
420 bool Before = false) {
421 return splitBasicBlock(I->getIterator(), BBName, Before);
422 }
423
424 /// Split the basic block into two basic blocks at the specified instruction
425 /// and insert the new basic blocks as the predecessor of the current block.
426 ///
427 /// This function ensures all instructions AFTER and including the specified
428 /// iterator \p I are part of the original basic block. All Instructions
429 /// BEFORE the iterator \p I are moved to the new BB and an unconditional
430 /// branch is added to the new BB. The new basic block is returned.
431 ///
432 /// Note that this only works on well formed basic blocks (must have a
433 /// terminator), and \p 'I' must not be the end of instruction list (which
434 /// would cause a degenerate basic block to be formed, having a terminator
435 /// inside of the basic block). \p 'I' cannot be a iterator for a PHINode
436 /// with multiple incoming blocks.
437 ///
438 /// Also note that this doesn't preserve any passes. To split blocks while
439 /// keeping loop information consistent, use the SplitBlockBefore utility
440 /// function.
441 BasicBlock *splitBasicBlockBefore(iterator I, const Twine &BBName = "");
442 BasicBlock *splitBasicBlockBefore(Instruction *I, const Twine &BBName = "") {
443 return splitBasicBlockBefore(I->getIterator(), BBName);
444 }
445
446 /// Returns true if there are any uses of this basic block other than
447 /// direct branches, switches, etc. to it.
448 bool hasAddressTaken() const {
449 return getBasicBlockBits().BlockAddressRefCount != 0;
450 }
451
452 /// Update all phi nodes in this basic block to refer to basic block \p New
453 /// instead of basic block \p Old.
454 void replacePhiUsesWith(BasicBlock *Old, BasicBlock *New);
455
456 /// Update all phi nodes in this basic block's successors to refer to basic
457 /// block \p New instead of basic block \p Old.
458 void replaceSuccessorsPhiUsesWith(BasicBlock *Old, BasicBlock *New);
459
460 /// Update all phi nodes in this basic block's successors to refer to basic
461 /// block \p New instead of to it.
462 void replaceSuccessorsPhiUsesWith(BasicBlock *New);
463
464 /// Return true if this basic block is an exception handling block.
465 bool isEHPad() const { return getFirstNonPHI()->isEHPad(); }
466
467 /// Return true if this basic block is a landing pad.
468 ///
469 /// Being a ``landing pad'' means that the basic block is the destination of
470 /// the 'unwind' edge of an invoke instruction.
471 bool isLandingPad() const;
472
473 /// Return the landingpad instruction associated with the landing pad.
474 const LandingPadInst *getLandingPadInst() const;
475 LandingPadInst *getLandingPadInst() {
476 return const_cast<LandingPadInst *>(
477 static_cast<const BasicBlock *>(this)->getLandingPadInst());
478 }
479
480 /// Return true if it is legal to hoist instructions into this block.
481 bool isLegalToHoistInto() const;
482
483 Optional<uint64_t> getIrrLoopHeaderWeight() const;
484
485 /// Returns true if the Order field of child Instructions is valid.
486 bool isInstrOrderValid() const {
487 return getBasicBlockBits().InstrOrderValid;
488 }
489
490 /// Mark instruction ordering invalid. Done on every instruction insert.
491 void invalidateOrders() {
492 validateInstrOrdering();
493 BasicBlockBits Bits = getBasicBlockBits();
494 Bits.InstrOrderValid = false;
495 setBasicBlockBits(Bits);
496 }
497
498 /// Renumber instructions and mark the ordering as valid.
499 void renumberInstructions();
500
501 /// Asserts that instruction order numbers are marked invalid, or that they
502 /// are in ascending order. This is constant time if the ordering is invalid,
503 /// and linear in the number of instructions if the ordering is valid. Callers
504 /// should be careful not to call this in ways that make common operations
505 /// O(n^2). For example, it takes O(n) time to assign order numbers to
506 /// instructions, so the order should be validated no more than once after
507 /// each ordering to ensure that transforms have the same algorithmic
508 /// complexity when asserts are enabled as when they are disabled.
509 void validateInstrOrdering() const;
510
511private:
512#if defined(_AIX) && (!defined(__GNUC__) || defined(__ibmxl__))
513// Except for GCC; by default, AIX compilers store bit-fields in 4-byte words
514// and give the `pack` pragma push semantics.
515#define BEGIN_TWO_BYTE_PACK() _Pragma("pack(2)")
516#define END_TWO_BYTE_PACK() _Pragma("pack(pop)")
517#else
518#define BEGIN_TWO_BYTE_PACK()
519#define END_TWO_BYTE_PACK()
520#endif
521
522 BEGIN_TWO_BYTE_PACK()
523 /// Bitfield to help interpret the bits in Value::SubclassData.
524 struct BasicBlockBits {
525 unsigned short BlockAddressRefCount : 15;
526 unsigned short InstrOrderValid : 1;
527 };
528 END_TWO_BYTE_PACK()
529
530#undef BEGIN_TWO_BYTE_PACK
531#undef END_TWO_BYTE_PACK
532
533 /// Safely reinterpret the subclass data bits to a more useful form.
534 BasicBlockBits getBasicBlockBits() const {
535 static_assert(sizeof(BasicBlockBits) == sizeof(unsigned short),
536 "too many bits for Value::SubclassData");
537 unsigned short ValueData = getSubclassDataFromValue();
538 BasicBlockBits AsBits;
539 memcpy(&AsBits, &ValueData, sizeof(AsBits));
540 return AsBits;
541 }
542
543 /// Reinterpret our subclass bits and store them back into Value.
544 void setBasicBlockBits(BasicBlockBits AsBits) {
545 unsigned short D;
546 memcpy(&D, &AsBits, sizeof(D));
547 Value::setValueSubclassData(D);
548 }
549
550 /// Increment the internal refcount of the number of BlockAddresses
551 /// referencing this BasicBlock by \p Amt.
552 ///
553 /// This is almost always 0, sometimes one possibly, but almost never 2, and
554 /// inconceivably 3 or more.
555 void AdjustBlockAddressRefCount(int Amt) {
556 BasicBlockBits Bits = getBasicBlockBits();
557 Bits.BlockAddressRefCount += Amt;
558 setBasicBlockBits(Bits);
559 assert(Bits.BlockAddressRefCount < 255 && "Refcount wrap-around");
560 }
561
562 /// Shadow Value::setValueSubclassData with a private forwarding method so
563 /// that any future subclasses cannot accidentally use it.
564 void setValueSubclassData(unsigned short D) {
565 Value::setValueSubclassData(D);
566 }
567};
568
569// Create wrappers for C Binding types (see CBindingWrapping.h).
570DEFINE_SIMPLE_CONVERSION_FUNCTIONS(BasicBlock, LLVMBasicBlockRef)
571
572/// Advance \p It while it points to a debug instruction and return the result.
573/// This assumes that \p It is not at the end of a block.
574BasicBlock::iterator skipDebugIntrinsics(BasicBlock::iterator It);
575
576#ifdef NDEBUG
577/// In release builds, this is a no-op. For !NDEBUG builds, the checks are
578/// implemented in the .cpp file to avoid circular header deps.
579inline void BasicBlock::validateInstrOrdering() const {}
580#endif
581
582} // end namespace llvm
583
584#endif // LLVM_IR_BASICBLOCK_H
585