LLVM  10.0.0svn
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  StatepointCall = isStatepoint(I) ? cast<CallBaseTy>(I) : nullptr;
80  }
81 
82  explicit StatepointBase(CallBaseTy *Call) {
83  StatepointCall = isStatepoint(Call) ? Call : nullptr;
84  }
85 
86 public:
87  using arg_iterator = typename CallBaseTy::const_op_iterator;
88 
89  enum {
90  IDPos = 0,
91  NumPatchBytesPos = 1,
92  CalledFunctionPos = 2,
93  NumCallArgsPos = 3,
94  FlagsPos = 4,
95  CallArgsBeginPos = 5,
96  };
97 
98  void *operator new(size_t, unsigned) = delete;
99  void *operator new(size_t s) = delete;
100 
101  explicit operator bool() const {
102  // We do not assign non-statepoint call instructions to StatepointCall.
103  return (bool)StatepointCall;
104  }
105 
106  /// Return the underlying call instruction.
107  CallBaseTy *getCall() const {
108  assert(*this && "check validity first!");
109  return StatepointCall;
110  }
111 
112  uint64_t getFlags() const {
113  return cast<ConstantInt>(getCall()->getArgOperand(FlagsPos))
114  ->getZExtValue();
115  }
116 
117  /// Return the ID associated with this statepoint.
118  uint64_t getID() const {
119  const Value *IDVal = getCall()->getArgOperand(IDPos);
120  return cast<ConstantInt>(IDVal)->getZExtValue();
121  }
122 
123  /// Return the number of patchable bytes associated with this statepoint.
125  const Value *NumPatchBytesVal = getCall()->getArgOperand(NumPatchBytesPos);
126  uint64_t NumPatchBytes =
127  cast<ConstantInt>(NumPatchBytesVal)->getZExtValue();
128  assert(isInt<32>(NumPatchBytes) && "should fit in 32 bits!");
129  return NumPatchBytes;
130  }
131 
132  /// Return the value actually being called or invoked.
133  ValueTy *getCalledValue() const {
134  return getCall()->getArgOperand(CalledFunctionPos);
135  }
136 
137  // FIXME: Migrate users of this to `getCall` and remove it.
138  InstructionTy *getInstruction() const { return getCall(); }
139 
140  /// Return the function being called if this is a direct call, otherwise
141  /// return null (if it's an indirect call).
142  FunTy *getCalledFunction() const {
143  return dyn_cast<Function>(getCalledValue());
144  }
145 
146  /// Return the caller function for this statepoint.
147  FunTy *getCaller() const { return getCall()->getCaller(); }
148 
149  /// Determine if the statepoint cannot unwind.
150  bool doesNotThrow() const {
152  return getCall()->doesNotThrow() || (F ? F->doesNotThrow() : false);
153  }
154 
155  /// Return the type of the value returned by the call underlying the
156  /// statepoint.
158  auto *FTy = cast<FunctionType>(
159  cast<PointerType>(getCalledValue()->getType())->getElementType());
160  return FTy->getReturnType();
161  }
162 
163  /// Number of arguments to be passed to the actual callee.
164  int getNumCallArgs() const {
165  const Value *NumCallArgsVal = getCall()->getArgOperand(NumCallArgsPos);
166  return cast<ConstantInt>(NumCallArgsVal)->getZExtValue();
167  }
168 
169  size_t arg_size() const { return getNumCallArgs(); }
171  assert(CallArgsBeginPos <= (int)getCall()->arg_size());
172  return getCall()->arg_begin() + CallArgsBeginPos;
173  }
175  auto I = arg_begin() + arg_size();
176  assert((getCall()->arg_end() - I) >= 0);
177  return I;
178  }
179 
180  ValueTy *getArgument(unsigned Index) {
181  assert(Index < arg_size() && "out of bounds!");
182  return *(arg_begin() + Index);
183  }
184 
185  /// range adapter for call arguments
187  return make_range(arg_begin(), arg_end());
188  }
189 
190  /// Return true if the call or the callee has the given attribute.
191  bool paramHasAttr(unsigned i, Attribute::AttrKind A) const {
193  return getCall()->paramHasAttr(i + CallArgsBeginPos, A) ||
194  (F ? F->getAttributes().hasAttribute(i, A) : false);
195  }
196 
197  /// Number of GC transition args.
199  const Value *NumGCTransitionArgs = *arg_end();
200  return cast<ConstantInt>(NumGCTransitionArgs)->getZExtValue();
201  }
203  auto I = arg_end() + 1;
204  assert((getCall()->arg_end() - I) >= 0);
205  return I;
206  }
208  auto I = gc_transition_args_begin() + getNumTotalGCTransitionArgs();
209  assert((getCall()->arg_end() - I) >= 0);
210  return I;
211  }
212 
213  /// range adapter for GC transition arguments
215  return make_range(gc_transition_args_begin(), gc_transition_args_end());
216  }
217 
218  /// Number of additional arguments excluding those intended
219  /// for garbage collection.
220  int getNumTotalVMSArgs() const {
221  const Value *NumVMSArgs = *gc_transition_args_end();
222  return cast<ConstantInt>(NumVMSArgs)->getZExtValue();
223  }
224 
226  auto I = gc_transition_args_end() + 1;
227  assert((getCall()->arg_end() - I) >= 0);
228  return I;
229  }
231  auto I = deopt_begin() + getNumTotalVMSArgs();
232  assert((getCall()->arg_end() - I) >= 0);
233  return I;
234  }
235 
236  /// range adapter for vm state arguments
238  return make_range(deopt_begin(), deopt_end());
239  }
240 
241  arg_iterator gc_args_begin() const { return deopt_end(); }
242  arg_iterator gc_args_end() const { return getCall()->arg_end(); }
243 
244  unsigned gcArgsStartIdx() const {
245  return gc_args_begin() - getCall()->op_begin();
246  }
247 
248  /// range adapter for gc arguments
250  return make_range(gc_args_begin(), gc_args_end());
251  }
252 
253  /// Get list of all gc reloactes linked to this statepoint
254  /// May contain several relocations for the same base/derived pair.
255  /// For example this could happen due to relocations on unwinding
256  /// path of invoke.
257  std::vector<const GCRelocateInst *> getRelocates() const;
258 
259  /// Get the experimental_gc_result call tied to this statepoint. Can be
260  /// nullptr if there isn't a gc_result tied to this statepoint. Guaranteed to
261  /// be a CallInst if non-null.
262  const GCResultInst *getGCResult() const {
263  for (auto *U : getInstruction()->users())
264  if (auto *GRI = dyn_cast<GCResultInst>(U))
265  return GRI;
266  return nullptr;
267  }
268 
269 #ifndef NDEBUG
270  /// Asserts if this statepoint is malformed. Common cases for failure
271  /// include incorrect length prefixes for variable length sections or
272  /// illegal values for parameters.
273  void verify() {
274  assert(getNumCallArgs() >= 0 &&
275  "number of arguments to actually callee can't be negative");
276 
277  // The internal asserts in the iterator accessors do the rest.
278  (void)arg_begin();
279  (void)arg_end();
280  (void)gc_transition_args_begin();
281  (void)gc_transition_args_end();
282  (void)deopt_begin();
283  (void)deopt_end();
284  (void)gc_args_begin();
285  (void)gc_args_end();
286  }
287 #endif
288 };
289 
290 /// A specialization of it's base class for read only access
291 /// to a gc.statepoint.
293  : public StatepointBase<const Function, const Instruction, const Value,
294  const CallBase> {
295  using Base = StatepointBase<const Function, const Instruction, const Value,
296  const CallBase>;
297 
298 public:
299  explicit ImmutableStatepoint(const Instruction *I) : Base(I) {}
300  explicit ImmutableStatepoint(const CallBase *Call) : Base(Call) {}
301 };
302 
303 /// A specialization of it's base class for read-write access
304 /// to a gc.statepoint.
306  : public StatepointBase<Function, Instruction, Value, CallBase> {
308 
309 public:
310  explicit Statepoint(Instruction *I) : Base(I) {}
311  explicit Statepoint(CallBase *Call) : Base(Call) {}
312 };
313 
314 /// Common base class for representing values projected from a statepoint.
315 /// Currently, the only projections available are gc.result and gc.relocate.
317 public:
318  static bool classof(const IntrinsicInst *I) {
319  return I->getIntrinsicID() == Intrinsic::experimental_gc_relocate ||
320  I->getIntrinsicID() == Intrinsic::experimental_gc_result;
321  }
322 
323  static bool classof(const Value *V) {
324  return isa<IntrinsicInst>(V) && classof(cast<IntrinsicInst>(V));
325  }
326 
327  /// Return true if this relocate is tied to the invoke statepoint.
328  /// This includes relocates which are on the unwinding path.
329  bool isTiedToInvoke() const {
330  const Value *Token = getArgOperand(0);
331 
332  return isa<LandingPadInst>(Token) || isa<InvokeInst>(Token);
333  }
334 
335  /// The statepoint with which this gc.relocate is associated.
336  const CallBase *getStatepoint() const {
337  const Value *Token = getArgOperand(0);
338 
339  // This takes care both of relocates for call statepoints and relocates
340  // on normal path of invoke statepoint.
341  if (!isa<LandingPadInst>(Token)) {
342  assert(isStatepoint(Token));
343  return cast<CallBase>(Token);
344  }
345 
346  // This relocate is on exceptional path of an invoke statepoint
347  const BasicBlock *InvokeBB =
348  cast<Instruction>(Token)->getParent()->getUniquePredecessor();
349 
350  assert(InvokeBB && "safepoints should have unique landingpads");
351  assert(InvokeBB->getTerminator() &&
352  "safepoint block should be well formed");
353  assert(isStatepoint(InvokeBB->getTerminator()));
354 
355  return cast<CallBase>(InvokeBB->getTerminator());
356  }
357 };
358 
359 /// Represents calls to the gc.relocate intrinsic.
361 public:
362  static bool classof(const IntrinsicInst *I) {
363  return I->getIntrinsicID() == Intrinsic::experimental_gc_relocate;
364  }
365 
366  static bool classof(const Value *V) {
367  return isa<IntrinsicInst>(V) && classof(cast<IntrinsicInst>(V));
368  }
369 
370  /// The index into the associate statepoint's argument list
371  /// which contains the base pointer of the pointer whose
372  /// relocation this gc.relocate describes.
373  unsigned getBasePtrIndex() const {
374  return cast<ConstantInt>(getArgOperand(1))->getZExtValue();
375  }
376 
377  /// The index into the associate statepoint's argument list which
378  /// contains the pointer whose relocation this gc.relocate describes.
379  unsigned getDerivedPtrIndex() const {
380  return cast<ConstantInt>(getArgOperand(2))->getZExtValue();
381  }
382 
383  Value *getBasePtr() const {
384  return *(getStatepoint()->arg_begin() + getBasePtrIndex());
385  }
386 
387  Value *getDerivedPtr() const {
388  return *(getStatepoint()->arg_begin() + getDerivedPtrIndex());
389  }
390 };
391 
392 /// Represents calls to the gc.result intrinsic.
394 public:
395  static bool classof(const IntrinsicInst *I) {
396  return I->getIntrinsicID() == Intrinsic::experimental_gc_result;
397  }
398 
399  static bool classof(const Value *V) {
400  return isa<IntrinsicInst>(V) && classof(cast<IntrinsicInst>(V));
401  }
402 };
403 
404 template <typename FunTy, typename InstructionTy, typename ValueTy,
405  typename CallBaseTy>
406 std::vector<const GCRelocateInst *>
408  const {
409  std::vector<const GCRelocateInst *> Result;
410 
411  // Search for relocated pointers. Note that working backwards from the
412  // gc_relocates ensures that we only get pairs which are actually relocated
413  // and used after the statepoint.
414  for (const User *U : StatepointCall->users())
415  if (auto *Relocate = dyn_cast<GCRelocateInst>(U))
416  Result.push_back(Relocate);
417 
418  auto *StatepointInvoke = dyn_cast<InvokeInst>(StatepointCall);
419  if (!StatepointInvoke)
420  return Result;
421 
422  // We need to scan thorough exceptional relocations if it is invoke statepoint
423  LandingPadInst *LandingPad = StatepointInvoke->getLandingPadInst();
424 
425  // Search for gc relocates that are attached to this landingpad.
426  for (const User *LandingPadUser : LandingPad->users()) {
427  if (auto *Relocate = dyn_cast<GCRelocateInst>(LandingPadUser))
428  Result.push_back(Relocate);
429  }
430  return Result;
431 }
432 
433 /// Call sites that get wrapped by a gc.statepoint (currently only in
434 /// RewriteStatepointsForGC and potentially in other passes in the future) can
435 /// have attributes that describe properties of gc.statepoint call they will be
436 /// eventually be wrapped in. This struct is used represent such directives.
440 
441  static const uint64_t DefaultStatepointID = 0xABCDEF00;
442  static const uint64_t DeoptBundleStatepointID = 0xABCDEF0F;
443 };
444 
445 /// Parse out statepoint directives from the function attributes present in \p
446 /// AS.
448 
449 /// Return \c true if the \p Attr is an attribute that is a statepoint
450 /// directive.
452 
453 } // end namespace llvm
454 
455 #endif // LLVM_IR_STATEPOINT_H
ImmutableStatepoint(const Instruction *I)
Definition: Statepoint.h:299
Represents calls to the gc.result intrinsic.
Definition: Statepoint.h:393
static bool classof(const Value *V)
Definition: Statepoint.h:366
ValueTy * getArgument(unsigned Index)
Definition: Statepoint.h:180
This class represents lattice values for constants.
Definition: AllocatorList.h:23
Statepoint(Instruction *I)
Definition: Statepoint.h:310
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:292
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:157
iterator_range< arg_iterator > gc_transition_args() const
range adapter for GC transition arguments
Definition: Statepoint.h:214
Base class for all callable instructions (InvokeInst and CallInst) Holds everything related to callin...
Definition: InstrTypes.h:1100
F(f)
CallBaseTy * getCall() const
Return the underlying call instruction.
Definition: Statepoint.h:107
Common base class for representing values projected from a statepoint.
Definition: Statepoint.h:316
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:87
const CallBase * getStatepoint() const
The statepoint with which this gc.relocate is associated.
Definition: Statepoint.h:336
void verify()
Asserts if this statepoint is malformed.
Definition: Statepoint.h:273
InstructionTy * getInstruction() const
Definition: Statepoint.h:138
iterator_range< arg_iterator > deopt_operands() const
range adapter for vm state arguments
Definition: Statepoint.h:237
Value * getDerivedPtr() const
Definition: Statepoint.h:387
StatepointBase(CallBaseTy *Call)
Definition: Statepoint.h:82
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:262
arg_iterator gc_args_begin() const
Definition: Statepoint.h:241
arg_iterator gc_transition_args_begin() const
Definition: Statepoint.h:202
static bool classof(const IntrinsicInst *I)
Definition: Statepoint.h:318
bool isStatepoint(const CallBase *Call)
Definition: Statepoint.cpp:20
iterator_range< arg_iterator > gc_args() const
range adapter for gc arguments
Definition: Statepoint.h:249
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:118
arg_iterator deopt_end() const
Definition: Statepoint.h:230
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:46
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:142
bool isTiedToInvoke() const
Return true if this relocate is tied to the invoke statepoint.
Definition: Statepoint.h:329
This file contains the declarations for the subclasses of Constant, which represent the different fla...
Optional< uint32_t > NumPatchBytes
Definition: Statepoint.h:438
FunTy * getCaller() const
Return the caller function for this statepoint.
Definition: Statepoint.h:147
arg_iterator arg_begin() const
Definition: Statepoint.h:170
arg_iterator gc_transition_args_end() const
Definition: Statepoint.h:207
A specialization of it&#39;s base class for read-write access to a gc.statepoint.
Definition: Statepoint.h:305
int getNumCallArgs() const
Number of arguments to be passed to the actual callee.
Definition: Statepoint.h:164
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:373
unsigned getDerivedPtrIndex() const
The index into the associate statepoint&#39;s argument list which contains the pointer whose relocation t...
Definition: Statepoint.h:379
size_t arg_size() const
Definition: Statepoint.h:169
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:538
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:362
static bool classof(const Value *V)
Definition: Statepoint.h:399
Statepoint(CallBase *Call)
Definition: Statepoint.h:311
constexpr bool isInt< 32 >(int64_t x)
Definition: MathExtras.h:345
arg_iterator gc_args_end() const
Definition: Statepoint.h:242
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:439
iterator_range< user_iterator > users()
Definition: Value.h:420
int getNumTotalGCTransitionArgs() const
Number of GC transition args.
Definition: Statepoint.h:198
Call sites that get wrapped by a gc.statepoint (currently only in RewriteStatepointsForGC and potenti...
Definition: Statepoint.h:437
iv users
Definition: IVUsers.cpp:51
static bool classof(const IntrinsicInst *I)
Definition: Statepoint.h:395
uint32_t getNumPatchBytes() const
Return the number of patchable bytes associated with this statepoint.
Definition: Statepoint.h:124
#define I(x, y, z)
Definition: MD5.cpp:58
static bool classof(const Value *V)
Definition: Statepoint.h:323
iterator_range< arg_iterator > call_args() const
range adapter for call arguments
Definition: Statepoint.h:186
arg_iterator arg_end() const
Definition: Statepoint.h:174
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
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:407
uint64_t getFlags() const
Definition: Statepoint.h:112
bool paramHasAttr(unsigned i, Attribute::AttrKind A) const
Return true if the call or the callee has the given attribute.
Definition: Statepoint.h:191
ValueTy * getCalledValue() const
Return the value actually being called or invoked.
Definition: Statepoint.h:133
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
ImmutableStatepoint(const CallBase *Call)
Definition: Statepoint.h:300
Represents calls to the gc.relocate intrinsic.
Definition: Statepoint.h:360
Mark the deopt arguments associated with the statepoint as only being "live-in".
LLVM Value Representation.
Definition: Value.h:74
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:220
Value * getBasePtr() const
Definition: Statepoint.h:383
A bitmask that includes all valid flags.
bool isGCResult(const CallBase *Call)
Definition: Statepoint.cpp:46
arg_iterator deopt_begin() const
Definition: Statepoint.h:225
bool doesNotThrow() const
Determine if the statepoint cannot unwind.
Definition: Statepoint.h:150
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:70
unsigned gcArgsStartIdx() const
Definition: Statepoint.h:244