LLVM  9.0.0svn
Statepoint.h
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1 //===- llvm/IR/Statepoint.h - gc.statepoint utilities -----------*- 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 utility functions and a wrapper class analogous to
10 // CallBase for accessing the fields of gc.statepoint, gc.relocate,
11 // gc.result intrinsics; and some general utilities helpful when dealing with
12 // gc.statepoint.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #ifndef LLVM_IR_STATEPOINT_H
17 #define LLVM_IR_STATEPOINT_H
18 
19 #include "llvm/ADT/Optional.h"
21 #include "llvm/IR/Attributes.h"
22 #include "llvm/IR/BasicBlock.h"
23 #include "llvm/IR/Constants.h"
24 #include "llvm/IR/Function.h"
25 #include "llvm/IR/Instruction.h"
26 #include "llvm/IR/Instructions.h"
27 #include "llvm/IR/IntrinsicInst.h"
28 #include "llvm/IR/Intrinsics.h"
29 #include "llvm/Support/Casting.h"
31 #include <cassert>
32 #include <cstddef>
33 #include <cstdint>
34 #include <vector>
35 
36 namespace llvm {
37 
38 /// The statepoint intrinsic accepts a set of flags as its third argument.
39 /// Valid values come out of this set.
40 enum class StatepointFlags {
41  None = 0,
42  GCTransition = 1, ///< Indicates that this statepoint is a transition from
43  ///< GC-aware code to code that is not GC-aware.
44  /// Mark the deopt arguments associated with the statepoint as only being
45  /// "live-in". By default, deopt arguments are "live-through". "live-through"
46  /// requires that they the value be live on entry, on exit, and at any point
47  /// during the call. "live-in" only requires the value be available at the
48  /// start of the call. In particular, "live-in" values can be placed in
49  /// unused argument registers or other non-callee saved registers.
50  DeoptLiveIn = 2,
51 
52  MaskAll = 3 ///< A bitmask that includes all valid flags.
53 };
54 
55 class GCRelocateInst;
56 class GCResultInst;
57 
58 bool isStatepoint(const CallBase *Call);
59 bool isStatepoint(const Value *V);
60 bool isStatepoint(const Value &V);
61 
62 bool isGCRelocate(const CallBase *Call);
63 bool isGCRelocate(const Value *V);
64 
65 bool isGCResult(const CallBase *Call);
66 bool isGCResult(const Value *V);
67 
68 /// A wrapper around a GC intrinsic call, this provides most of the actual
69 /// functionality for Statepoint and ImmutableStatepoint. It is
70 /// templatized to allow easily specializing of const and non-const
71 /// concrete subtypes.
72 template <typename FunTy, typename InstructionTy, typename ValueTy,
73  typename CallBaseTy>
75  CallBaseTy *StatepointCall;
76 
77 protected:
78  explicit StatepointBase(InstructionTy *I) {
79  if (isStatepoint(I)) {
80  StatepointCall = cast<CallBaseTy>(I);
81  }
82  }
83 
84  explicit StatepointBase(CallBaseTy *Call) {
85  if (isStatepoint(Call))
86  StatepointCall = Call;
87  }
88 
89 public:
90  using arg_iterator = typename CallBaseTy::const_op_iterator;
91 
92  enum {
93  IDPos = 0,
94  NumPatchBytesPos = 1,
95  CalledFunctionPos = 2,
96  NumCallArgsPos = 3,
97  FlagsPos = 4,
98  CallArgsBeginPos = 5,
99  };
100 
101  void *operator new(size_t, unsigned) = delete;
102  void *operator new(size_t s) = delete;
103 
104  explicit operator bool() const {
105  // We do not assign non-statepoint call instructions to StatepointCall.
106  return (bool)StatepointCall;
107  }
108 
109  /// Return the underlying call instruction.
110  CallBaseTy *getCall() const {
111  assert(*this && "check validity first!");
112  return StatepointCall;
113  }
114 
115  uint64_t getFlags() const {
116  return cast<ConstantInt>(getCall()->getArgOperand(FlagsPos))
117  ->getZExtValue();
118  }
119 
120  /// Return the ID associated with this statepoint.
121  uint64_t getID() const {
122  const Value *IDVal = getCall()->getArgOperand(IDPos);
123  return cast<ConstantInt>(IDVal)->getZExtValue();
124  }
125 
126  /// Return the number of patchable bytes associated with this statepoint.
128  const Value *NumPatchBytesVal = getCall()->getArgOperand(NumPatchBytesPos);
129  uint64_t NumPatchBytes =
130  cast<ConstantInt>(NumPatchBytesVal)->getZExtValue();
131  assert(isInt<32>(NumPatchBytes) && "should fit in 32 bits!");
132  return NumPatchBytes;
133  }
134 
135  /// Return the value actually being called or invoked.
136  ValueTy *getCalledValue() const {
137  return getCall()->getArgOperand(CalledFunctionPos);
138  }
139 
140  // FIXME: Migrate users of this to `getCall` and remove it.
141  InstructionTy *getInstruction() const { return getCall(); }
142 
143  /// Return the function being called if this is a direct call, otherwise
144  /// return null (if it's an indirect call).
145  FunTy *getCalledFunction() const {
146  return dyn_cast<Function>(getCalledValue());
147  }
148 
149  /// Return the caller function for this statepoint.
150  FunTy *getCaller() const { return getCall()->getCaller(); }
151 
152  /// Determine if the statepoint cannot unwind.
153  bool doesNotThrow() const {
155  return getCall()->doesNotThrow() || (F ? F->doesNotThrow() : false);
156  }
157 
158  /// Return the type of the value returned by the call underlying the
159  /// statepoint.
161  auto *FTy = cast<FunctionType>(
162  cast<PointerType>(getCalledValue()->getType())->getElementType());
163  return FTy->getReturnType();
164  }
165 
166  /// Number of arguments to be passed to the actual callee.
167  int getNumCallArgs() const {
168  const Value *NumCallArgsVal = getCall()->getArgOperand(NumCallArgsPos);
169  return cast<ConstantInt>(NumCallArgsVal)->getZExtValue();
170  }
171 
172  size_t arg_size() const { return getNumCallArgs(); }
174  assert(CallArgsBeginPos <= (int)getCall()->arg_size());
175  return getCall()->arg_begin() + CallArgsBeginPos;
176  }
178  auto I = arg_begin() + arg_size();
179  assert((getCall()->arg_end() - I) >= 0);
180  return I;
181  }
182 
183  ValueTy *getArgument(unsigned Index) {
184  assert(Index < arg_size() && "out of bounds!");
185  return *(arg_begin() + Index);
186  }
187 
188  /// range adapter for call arguments
190  return make_range(arg_begin(), arg_end());
191  }
192 
193  /// Return true if the call or the callee has the given attribute.
194  bool paramHasAttr(unsigned i, Attribute::AttrKind A) const {
196  return getCall()->paramHasAttr(i + CallArgsBeginPos, A) ||
197  (F ? F->getAttributes().hasAttribute(i, A) : false);
198  }
199 
200  /// Number of GC transition args.
202  const Value *NumGCTransitionArgs = *arg_end();
203  return cast<ConstantInt>(NumGCTransitionArgs)->getZExtValue();
204  }
206  auto I = arg_end() + 1;
207  assert((getCall()->arg_end() - I) >= 0);
208  return I;
209  }
211  auto I = gc_transition_args_begin() + getNumTotalGCTransitionArgs();
212  assert((getCall()->arg_end() - I) >= 0);
213  return I;
214  }
215 
216  /// range adapter for GC transition arguments
218  return make_range(gc_transition_args_begin(), gc_transition_args_end());
219  }
220 
221  /// Number of additional arguments excluding those intended
222  /// for garbage collection.
223  int getNumTotalVMSArgs() const {
224  const Value *NumVMSArgs = *gc_transition_args_end();
225  return cast<ConstantInt>(NumVMSArgs)->getZExtValue();
226  }
227 
229  auto I = gc_transition_args_end() + 1;
230  assert((getCall()->arg_end() - I) >= 0);
231  return I;
232  }
234  auto I = deopt_begin() + getNumTotalVMSArgs();
235  assert((getCall()->arg_end() - I) >= 0);
236  return I;
237  }
238 
239  /// range adapter for vm state arguments
241  return make_range(deopt_begin(), deopt_end());
242  }
243 
244  arg_iterator gc_args_begin() const { return deopt_end(); }
245  arg_iterator gc_args_end() const { return getCall()->arg_end(); }
246 
247  unsigned gcArgsStartIdx() const {
248  return gc_args_begin() - getCall()->op_begin();
249  }
250 
251  /// range adapter for gc arguments
253  return make_range(gc_args_begin(), gc_args_end());
254  }
255 
256  /// Get list of all gc reloactes linked to this statepoint
257  /// May contain several relocations for the same base/derived pair.
258  /// For example this could happen due to relocations on unwinding
259  /// path of invoke.
260  std::vector<const GCRelocateInst *> getRelocates() const;
261 
262  /// Get the experimental_gc_result call tied to this statepoint. Can be
263  /// nullptr if there isn't a gc_result tied to this statepoint. Guaranteed to
264  /// be a CallInst if non-null.
265  const GCResultInst *getGCResult() const {
266  for (auto *U : getInstruction()->users())
267  if (auto *GRI = dyn_cast<GCResultInst>(U))
268  return GRI;
269  return nullptr;
270  }
271 
272 #ifndef NDEBUG
273  /// Asserts if this statepoint is malformed. Common cases for failure
274  /// include incorrect length prefixes for variable length sections or
275  /// illegal values for parameters.
276  void verify() {
277  assert(getNumCallArgs() >= 0 &&
278  "number of arguments to actually callee can't be negative");
279 
280  // The internal asserts in the iterator accessors do the rest.
281  (void)arg_begin();
282  (void)arg_end();
283  (void)gc_transition_args_begin();
284  (void)gc_transition_args_end();
285  (void)deopt_begin();
286  (void)deopt_end();
287  (void)gc_args_begin();
288  (void)gc_args_end();
289  }
290 #endif
291 };
292 
293 /// A specialization of it's base class for read only access
294 /// to a gc.statepoint.
296  : public StatepointBase<const Function, const Instruction, const Value,
297  const CallBase> {
298  using Base = StatepointBase<const Function, const Instruction, const Value,
299  const CallBase>;
300 
301 public:
302  explicit ImmutableStatepoint(const Instruction *I) : Base(I) {}
303  explicit ImmutableStatepoint(const CallBase *Call) : Base(Call) {}
304 };
305 
306 /// A specialization of it's base class for read-write access
307 /// to a gc.statepoint.
309  : public StatepointBase<Function, Instruction, Value, CallBase> {
311 
312 public:
313  explicit Statepoint(Instruction *I) : Base(I) {}
314  explicit Statepoint(CallBase *Call) : Base(Call) {}
315 };
316 
317 /// Common base class for representing values projected from a statepoint.
318 /// Currently, the only projections available are gc.result and gc.relocate.
320 public:
321  static bool classof(const IntrinsicInst *I) {
322  return I->getIntrinsicID() == Intrinsic::experimental_gc_relocate ||
323  I->getIntrinsicID() == Intrinsic::experimental_gc_result;
324  }
325 
326  static bool classof(const Value *V) {
327  return isa<IntrinsicInst>(V) && classof(cast<IntrinsicInst>(V));
328  }
329 
330  /// Return true if this relocate is tied to the invoke statepoint.
331  /// This includes relocates which are on the unwinding path.
332  bool isTiedToInvoke() const {
333  const Value *Token = getArgOperand(0);
334 
335  return isa<LandingPadInst>(Token) || isa<InvokeInst>(Token);
336  }
337 
338  /// The statepoint with which this gc.relocate is associated.
339  const CallBase *getStatepoint() const {
340  const Value *Token = getArgOperand(0);
341 
342  // This takes care both of relocates for call statepoints and relocates
343  // on normal path of invoke statepoint.
344  if (!isa<LandingPadInst>(Token)) {
345  assert(isStatepoint(Token));
346  return cast<CallBase>(Token);
347  }
348 
349  // This relocate is on exceptional path of an invoke statepoint
350  const BasicBlock *InvokeBB =
351  cast<Instruction>(Token)->getParent()->getUniquePredecessor();
352 
353  assert(InvokeBB && "safepoints should have unique landingpads");
354  assert(InvokeBB->getTerminator() &&
355  "safepoint block should be well formed");
356  assert(isStatepoint(InvokeBB->getTerminator()));
357 
358  return cast<CallBase>(InvokeBB->getTerminator());
359  }
360 };
361 
362 /// Represents calls to the gc.relocate intrinsic.
364 public:
365  static bool classof(const IntrinsicInst *I) {
366  return I->getIntrinsicID() == Intrinsic::experimental_gc_relocate;
367  }
368 
369  static bool classof(const Value *V) {
370  return isa<IntrinsicInst>(V) && classof(cast<IntrinsicInst>(V));
371  }
372 
373  /// The index into the associate statepoint's argument list
374  /// which contains the base pointer of the pointer whose
375  /// relocation this gc.relocate describes.
376  unsigned getBasePtrIndex() const {
377  return cast<ConstantInt>(getArgOperand(1))->getZExtValue();
378  }
379 
380  /// The index into the associate statepoint's argument list which
381  /// contains the pointer whose relocation this gc.relocate describes.
382  unsigned getDerivedPtrIndex() const {
383  return cast<ConstantInt>(getArgOperand(2))->getZExtValue();
384  }
385 
386  Value *getBasePtr() const {
387  return *(getStatepoint()->arg_begin() + getBasePtrIndex());
388  }
389 
390  Value *getDerivedPtr() const {
391  return *(getStatepoint()->arg_begin() + getDerivedPtrIndex());
392  }
393 };
394 
395 /// Represents calls to the gc.result intrinsic.
397 public:
398  static bool classof(const IntrinsicInst *I) {
399  return I->getIntrinsicID() == Intrinsic::experimental_gc_result;
400  }
401 
402  static bool classof(const Value *V) {
403  return isa<IntrinsicInst>(V) && classof(cast<IntrinsicInst>(V));
404  }
405 };
406 
407 template <typename FunTy, typename InstructionTy, typename ValueTy,
408  typename CallBaseTy>
409 std::vector<const GCRelocateInst *>
411  const {
412  std::vector<const GCRelocateInst *> Result;
413 
414  // Search for relocated pointers. Note that working backwards from the
415  // gc_relocates ensures that we only get pairs which are actually relocated
416  // and used after the statepoint.
417  for (const User *U : StatepointCall->users())
418  if (auto *Relocate = dyn_cast<GCRelocateInst>(U))
419  Result.push_back(Relocate);
420 
421  auto *StatepointInvoke = dyn_cast<InvokeInst>(StatepointCall);
422  if (!StatepointInvoke)
423  return Result;
424 
425  // We need to scan thorough exceptional relocations if it is invoke statepoint
426  LandingPadInst *LandingPad = StatepointInvoke->getLandingPadInst();
427 
428  // Search for gc relocates that are attached to this landingpad.
429  for (const User *LandingPadUser : LandingPad->users()) {
430  if (auto *Relocate = dyn_cast<GCRelocateInst>(LandingPadUser))
431  Result.push_back(Relocate);
432  }
433  return Result;
434 }
435 
436 /// Call sites that get wrapped by a gc.statepoint (currently only in
437 /// RewriteStatepointsForGC and potentially in other passes in the future) can
438 /// have attributes that describe properties of gc.statepoint call they will be
439 /// eventually be wrapped in. This struct is used represent such directives.
443 
444  static const uint64_t DefaultStatepointID = 0xABCDEF00;
445  static const uint64_t DeoptBundleStatepointID = 0xABCDEF0F;
446 };
447 
448 /// Parse out statepoint directives from the function attributes present in \p
449 /// AS.
451 
452 /// Return \c true if the \p Attr is an attribute that is a statepoint
453 /// directive.
455 
456 } // end namespace llvm
457 
458 #endif // LLVM_IR_STATEPOINT_H
ImmutableStatepoint(const Instruction *I)
Definition: Statepoint.h:302
Represents calls to the gc.result intrinsic.
Definition: Statepoint.h:396
static bool classof(const Value *V)
Definition: Statepoint.h:369
ValueTy * getArgument(unsigned Index)
Definition: Statepoint.h:183
This class represents lattice values for constants.
Definition: AllocatorList.h:23
Statepoint(Instruction *I)
Definition: Statepoint.h:313
StatepointFlags
The statepoint intrinsic accepts a set of flags as its third argument.
Definition: Statepoint.h:40
StatepointDirectives parseStatepointDirectivesFromAttrs(AttributeList AS)
Parse out statepoint directives from the function attributes present in AS.
Definition: Statepoint.cpp:60
A specialization of it&#39;s base class for read only access to a gc.statepoint.
Definition: Statepoint.h:295
This provides a very simple, boring adaptor for a begin and end iterator into a range type...
Type * getActualReturnType() const
Return the type of the value returned by the call underlying the statepoint.
Definition: Statepoint.h:160
iterator_range< arg_iterator > gc_transition_args() const
range adapter for GC transition arguments
Definition: Statepoint.h:217
Base class for all callable instructions (InvokeInst and CallInst) Holds everything related to callin...
Definition: InstrTypes.h:1014
F(f)
CallBaseTy * getCall() const
Return the underlying call instruction.
Definition: Statepoint.h:110
Common base class for representing values projected from a statepoint.
Definition: Statepoint.h:319
bool hasAttribute(unsigned Index, Attribute::AttrKind Kind) const
Return true if the attribute exists at the given index.
typename CallBase ::const_op_iterator arg_iterator
Definition: Statepoint.h:90
const CallBase * getStatepoint() const
The statepoint with which this gc.relocate is associated.
Definition: Statepoint.h:339
void verify()
Asserts if this statepoint is malformed.
Definition: Statepoint.h:276
InstructionTy * getInstruction() const
Definition: Statepoint.h:141
iterator_range< arg_iterator > deopt_operands() const
range adapter for vm state arguments
Definition: Statepoint.h:240
Value * getDerivedPtr() const
Definition: Statepoint.h:390
StatepointBase(CallBaseTy *Call)
Definition: Statepoint.h:84
This file contains the simple types necessary to represent the attributes associated with functions a...
const GCResultInst * getGCResult() const
Get the experimental_gc_result call tied to this statepoint.
Definition: Statepoint.h:265
arg_iterator gc_args_begin() const
Definition: Statepoint.h:244
arg_iterator gc_transition_args_begin() const
Definition: Statepoint.h:205
static bool classof(const IntrinsicInst *I)
Definition: Statepoint.h:321
bool isStatepoint(const CallBase *Call)
Definition: Statepoint.cpp:20
iterator_range< arg_iterator > gc_args() const
range adapter for gc arguments
Definition: Statepoint.h:252
AttributeList getAttributes() const
Return the attribute list for this Function.
Definition: Function.h:223
uint64_t getID() const
Return the ID associated with this statepoint.
Definition: Statepoint.h:121
arg_iterator deopt_end() const
Definition: Statepoint.h:233
The landingpad instruction holds all of the information necessary to generate correct exception handl...
LLVM Basic Block Representation.
Definition: BasicBlock.h:57
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
FunTy * getCalledFunction() const
Return the function being called if this is a direct call, otherwise return null (if it&#39;s an indirect...
Definition: Statepoint.h:145
bool isTiedToInvoke() const
Return true if this relocate is tied to the invoke statepoint.
Definition: Statepoint.h:332
This file contains the declarations for the subclasses of Constant, which represent the different fla...
Optional< uint32_t > NumPatchBytes
Definition: Statepoint.h:441
FunTy * getCaller() const
Return the caller function for this statepoint.
Definition: Statepoint.h:150
arg_iterator arg_begin() const
Definition: Statepoint.h:173
arg_iterator gc_transition_args_end() const
Definition: Statepoint.h:210
A specialization of it&#39;s base class for read-write access to a gc.statepoint.
Definition: Statepoint.h:308
int getNumCallArgs() const
Number of arguments to be passed to the actual callee.
Definition: Statepoint.h:167
StatepointBase(InstructionTy *I)
Definition: Statepoint.h:78
unsigned getBasePtrIndex() const
The index into the associate statepoint&#39;s argument list which contains the base pointer of the pointe...
Definition: Statepoint.h:376
unsigned getDerivedPtrIndex() const
The index into the associate statepoint&#39;s argument list which contains the pointer whose relocation t...
Definition: Statepoint.h:382
size_t arg_size() const
Definition: Statepoint.h:172
bool isGCRelocate(const CallBase *Call)
Definition: Statepoint.cpp:36
Intrinsic::ID getIntrinsicID() const
Return the intrinsic ID of this intrinsic.
Definition: IntrinsicInst.h:50
bool doesNotThrow() const
Determine if the function cannot unwind.
Definition: Function.h:519
iterator_range< T > make_range(T x, T y)
Convenience function for iterating over sub-ranges.
static bool classof(const IntrinsicInst *I)
Definition: Statepoint.h:365
static bool classof(const Value *V)
Definition: Statepoint.h:402
Statepoint(CallBase *Call)
Definition: Statepoint.h:314
constexpr bool isInt< 32 >(int64_t x)
Definition: MathExtras.h:308
arg_iterator gc_args_end() const
Definition: Statepoint.h:245
Indicates that this statepoint is a transition from GC-aware code to code that is not GC-aware...
static const Function * getCalledFunction(const Value *V, bool LookThroughBitCast, bool &IsNoBuiltin)
A range adaptor for a pair of iterators.
bool isStatepointDirectiveAttr(Attribute Attr)
Return true if the Attr is an attribute that is a statepoint directive.
Definition: Statepoint.cpp:54
Optional< uint64_t > StatepointID
Definition: Statepoint.h:442
iterator_range< user_iterator > users()
Definition: Value.h:399
int getNumTotalGCTransitionArgs() const
Number of GC transition args.
Definition: Statepoint.h:201
Call sites that get wrapped by a gc.statepoint (currently only in RewriteStatepointsForGC and potenti...
Definition: Statepoint.h:440
iv users
Definition: IVUsers.cpp:51
static bool classof(const IntrinsicInst *I)
Definition: Statepoint.h:398
uint32_t getNumPatchBytes() const
Return the number of patchable bytes associated with this statepoint.
Definition: Statepoint.h:127
#define I(x, y, z)
Definition: MD5.cpp:58
static bool classof(const Value *V)
Definition: Statepoint.h:326
iterator_range< arg_iterator > call_args() const
range adapter for call arguments
Definition: Statepoint.h:189
arg_iterator arg_end() const
Definition: Statepoint.h:177
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:322
std::vector< const GCRelocateInst * > getRelocates() const
Get list of all gc reloactes linked to this statepoint May contain several relocations for the same b...
Definition: Statepoint.h:410
uint64_t getFlags() const
Definition: Statepoint.h:115
bool paramHasAttr(unsigned i, Attribute::AttrKind A) const
Return true if the call or the callee has the given attribute.
Definition: Statepoint.h:194
ValueTy * getCalledValue() const
Return the value actually being called or invoked.
Definition: Statepoint.h:136
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
ImmutableStatepoint(const CallBase *Call)
Definition: Statepoint.h:303
Represents calls to the gc.relocate intrinsic.
Definition: Statepoint.h:363
Mark the deopt arguments associated with the statepoint as only being "live-in".
LLVM Value Representation.
Definition: Value.h:72
A wrapper around a GC intrinsic call, this provides most of the actual functionality for Statepoint a...
Definition: Statepoint.h:74
static const Function * getParent(const Value *V)
Invoke instruction.
int getNumTotalVMSArgs() const
Number of additional arguments excluding those intended for garbage collection.
Definition: Statepoint.h:223
Value * getBasePtr() const
Definition: Statepoint.h:386
A bitmask that includes all valid flags.
bool isGCResult(const CallBase *Call)
Definition: Statepoint.cpp:46
arg_iterator deopt_begin() const
Definition: Statepoint.h:228
bool doesNotThrow() const
Determine if the statepoint cannot unwind.
Definition: Statepoint.h:153
A wrapper class for inspecting calls to intrinsic functions.
Definition: IntrinsicInst.h:43
AttrKind
This enumeration lists the attributes that can be associated with parameters, function results...
Definition: Attributes.h:69
unsigned gcArgsStartIdx() const
Definition: Statepoint.h:247