LLVM 19.0.0git
StackMaps.h
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1//===- StackMaps.h - StackMaps ----------------------------------*- 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#ifndef LLVM_CODEGEN_STACKMAPS_H
10#define LLVM_CODEGEN_STACKMAPS_H
11
12#include "llvm/ADT/MapVector.h"
15#include "llvm/IR/CallingConv.h"
16#include "llvm/Support/Debug.h"
17#include <algorithm>
18#include <cassert>
19#include <cstdint>
20#include <vector>
21
22namespace llvm {
23
24class AsmPrinter;
25class MCSymbol;
26class MCExpr;
27class MCStreamer;
28class raw_ostream;
29class TargetRegisterInfo;
30
31/// MI-level stackmap operands.
32///
33/// MI stackmap operations take the form:
34/// <id>, <numBytes>, live args...
36public:
37 /// Enumerate the meta operands.
38 enum { IDPos, NBytesPos };
39
40private:
41 const MachineInstr* MI;
42
43public:
44 explicit StackMapOpers(const MachineInstr *MI);
45
46 /// Return the ID for the given stackmap
47 uint64_t getID() const { return MI->getOperand(IDPos).getImm(); }
48
49 /// Return the number of patchable bytes the given stackmap should emit.
51 return MI->getOperand(NBytesPos).getImm();
52 }
53
54 /// Get the operand index of the variable list of non-argument operands.
55 /// These hold the "live state".
56 unsigned getVarIdx() const {
57 // Skip ID, nShadowBytes.
58 return 2;
59 }
60};
61
62/// MI-level patchpoint operands.
63///
64/// MI patchpoint operations take the form:
65/// [<def>], <id>, <numBytes>, <target>, <numArgs>, <cc>, ...
66///
67/// IR patchpoint intrinsics do not have the <cc> operand because calling
68/// convention is part of the subclass data.
69///
70/// SD patchpoint nodes do not have a def operand because it is part of the
71/// SDValue.
72///
73/// Patchpoints following the anyregcc convention are handled specially. For
74/// these, the stack map also records the location of the return value and
75/// arguments.
77public:
78 /// Enumerate the meta operands.
80
81private:
82 const MachineInstr *MI;
83 bool HasDef;
84
85 unsigned getMetaIdx(unsigned Pos = 0) const {
86 assert(Pos < MetaEnd && "Meta operand index out of range.");
87 return (HasDef ? 1 : 0) + Pos;
88 }
89
90 const MachineOperand &getMetaOper(unsigned Pos) const {
91 return MI->getOperand(getMetaIdx(Pos));
92 }
93
94public:
95 explicit PatchPointOpers(const MachineInstr *MI);
96
97 bool isAnyReg() const { return (getCallingConv() == CallingConv::AnyReg); }
98 bool hasDef() const { return HasDef; }
99
100 /// Return the ID for the given patchpoint.
101 uint64_t getID() const { return getMetaOper(IDPos).getImm(); }
102
103 /// Return the number of patchable bytes the given patchpoint should emit.
105 return getMetaOper(NBytesPos).getImm();
106 }
107
108 /// Returns the target of the underlying call.
110 return getMetaOper(TargetPos);
111 }
112
113 /// Returns the calling convention
115 return getMetaOper(CCPos).getImm();
116 }
117
118 unsigned getArgIdx() const { return getMetaIdx() + MetaEnd; }
119
120 /// Return the number of call arguments
122 return MI->getOperand(getMetaIdx(NArgPos)).getImm();
123 }
124
125 /// Get the operand index of the variable list of non-argument operands.
126 /// These hold the "live state".
127 unsigned getVarIdx() const {
128 return getMetaIdx() + MetaEnd + getNumCallArgs();
129 }
130
131 /// Get the index at which stack map locations will be recorded.
132 /// Arguments are not recorded unless the anyregcc convention is used.
133 unsigned getStackMapStartIdx() const {
134 if (isAnyReg())
135 return getArgIdx();
136 return getVarIdx();
137 }
138
139 /// Get the next scratch register operand index.
140 unsigned getNextScratchIdx(unsigned StartIdx = 0) const;
141};
142
143/// MI-level Statepoint operands
144///
145/// Statepoint operands take the form:
146/// <id>, <num patch bytes >, <num call arguments>, <call target>,
147/// [call arguments...],
148/// <StackMaps::ConstantOp>, <calling convention>,
149/// <StackMaps::ConstantOp>, <statepoint flags>,
150/// <StackMaps::ConstantOp>, <num deopt args>, [deopt args...],
151/// <StackMaps::ConstantOp>, <num gc pointer args>, [gc pointer args...],
152/// <StackMaps::ConstantOp>, <num gc allocas>, [gc allocas args...],
153/// <StackMaps::ConstantOp>, <num entries in gc map>, [base/derived pairs]
154/// base/derived pairs in gc map are logical indices into <gc pointer args>
155/// section.
156/// All gc pointers assigned to VRegs produce new value (in form of MI Def
157/// operand) and are tied to it.
159 // TODO:: we should change the STATEPOINT representation so that CC and
160 // Flags should be part of meta operands, with args and deopt operands, and
161 // gc operands all prefixed by their length and a type code. This would be
162 // much more consistent.
163
164 // These values are absolute offsets into the operands of the statepoint
165 // instruction.
166 enum { IDPos, NBytesPos, NCallArgsPos, CallTargetPos, MetaEnd };
167
168 // These values are relative offsets from the start of the statepoint meta
169 // arguments (i.e. the end of the call arguments).
170 enum { CCOffset = 1, FlagsOffset = 3, NumDeoptOperandsOffset = 5 };
171
172public:
173 explicit StatepointOpers(const MachineInstr *MI) : MI(MI) {
174 NumDefs = MI->getNumDefs();
175 }
176
177 /// Get index of statepoint ID operand.
178 unsigned getIDPos() const { return NumDefs + IDPos; }
179
180 /// Get index of Num Patch Bytes operand.
181 unsigned getNBytesPos() const { return NumDefs + NBytesPos; }
182
183 /// Get index of Num Call Arguments operand.
184 unsigned getNCallArgsPos() const { return NumDefs + NCallArgsPos; }
185
186 /// Get starting index of non call related arguments
187 /// (calling convention, statepoint flags, vm state and gc state).
188 unsigned getVarIdx() const {
189 return MI->getOperand(NumDefs + NCallArgsPos).getImm() + MetaEnd + NumDefs;
190 }
191
192 /// Get index of Calling Convention operand.
193 unsigned getCCIdx() const { return getVarIdx() + CCOffset; }
194
195 /// Get index of Flags operand.
196 unsigned getFlagsIdx() const { return getVarIdx() + FlagsOffset; }
197
198 /// Get index of Number Deopt Arguments operand.
199 unsigned getNumDeoptArgsIdx() const {
200 return getVarIdx() + NumDeoptOperandsOffset;
201 }
202
203 /// Return the ID for the given statepoint.
204 uint64_t getID() const { return MI->getOperand(NumDefs + IDPos).getImm(); }
205
206 /// Return the number of patchable bytes the given statepoint should emit.
208 return MI->getOperand(NumDefs + NBytesPos).getImm();
209 }
210
211 /// Return the target of the underlying call.
213 return MI->getOperand(NumDefs + CallTargetPos);
214 }
215
216 /// Return the calling convention.
218 return MI->getOperand(getCCIdx()).getImm();
219 }
220
221 /// Return the statepoint flags.
222 uint64_t getFlags() const { return MI->getOperand(getFlagsIdx()).getImm(); }
223
225 return MI->getOperand(getNumDeoptArgsIdx()).getImm();
226 }
227
228 /// Get index of number of gc map entries.
229 unsigned getNumGcMapEntriesIdx();
230
231 /// Get index of number of gc allocas.
232 unsigned getNumAllocaIdx();
233
234 /// Get index of number of GC pointers.
235 unsigned getNumGCPtrIdx();
236
237 /// Get index of first GC pointer operand of -1 if there are none.
238 int getFirstGCPtrIdx();
239
240 /// Get vector of base/derived pairs from statepoint.
241 /// Elements are indices into GC Pointer operand list (logical).
242 /// Returns number of elements in GCMap.
243 unsigned
244 getGCPointerMap(SmallVectorImpl<std::pair<unsigned, unsigned>> &GCMap);
245
246 /// Return true if Reg is used only in operands which can be folded to
247 /// stack usage.
248 bool isFoldableReg(Register Reg) const;
249
250 /// Return true if Reg is used only in operands of MI which can be folded to
251 /// stack usage and MI is a statepoint instruction.
252 static bool isFoldableReg(const MachineInstr *MI, Register Reg);
253
254private:
255 const MachineInstr *MI;
256 unsigned NumDefs;
257};
258
260public:
261 struct Location {
269 };
273 int32_t Offset = 0;
274
275 Location() = default;
277 : Type(Type), Size(Size), Reg(Reg), Offset(Offset) {}
278 };
279
280 struct LiveOutReg {
284
285 LiveOutReg() = default;
288 };
289
290 // OpTypes are used to encode information about the following logical
291 // operand (which may consist of several MachineOperands) for the
292 // OpParser.
293 using OpType = enum { DirectMemRefOp, IndirectMemRefOp, ConstantOp };
294
296
297 /// Get index of next meta operand.
298 /// Similar to parseOperand, but does not actually parses operand meaning.
299 static unsigned getNextMetaArgIdx(const MachineInstr *MI, unsigned CurIdx);
300
301 void reset() {
302 CSInfos.clear();
303 ConstPool.clear();
304 FnInfos.clear();
305 }
306
310
314
315 FunctionInfo() = default;
317 };
318
320 const MCExpr *CSOffsetExpr = nullptr;
324
325 CallsiteInfo() = default;
330 };
331
333 using CallsiteInfoList = std::vector<CallsiteInfo>;
334
335 /// Generate a stackmap record for a stackmap instruction.
336 ///
337 /// MI must be a raw STACKMAP, not a PATCHPOINT.
338 void recordStackMap(const MCSymbol &L,
339 const MachineInstr &MI);
340
341 /// Generate a stackmap record for a patchpoint instruction.
342 void recordPatchPoint(const MCSymbol &L,
343 const MachineInstr &MI);
344
345 /// Generate a stackmap record for a statepoint instruction.
346 void recordStatepoint(const MCSymbol &L,
347 const MachineInstr &MI);
348
349 /// If there is any stack map data, create a stack map section and serialize
350 /// the map info into it. This clears the stack map data structures
351 /// afterwards.
353
354 /// Get call site info.
355 CallsiteInfoList &getCSInfos() { return CSInfos; }
356
357 /// Get function info.
358 FnInfoMap &getFnInfos() { return FnInfos; }
359
360private:
361 static const char *WSMP;
362
363 AsmPrinter &AP;
364 CallsiteInfoList CSInfos;
365 ConstantPool ConstPool;
366 FnInfoMap FnInfos;
367
369 parseOperand(MachineInstr::const_mop_iterator MOI,
371 LiveOutVec &LiveOuts);
372
373 /// Specialized parser of statepoint operands.
374 /// They do not directly correspond to StackMap record entries.
375 void parseStatepointOpers(const MachineInstr &MI,
378 LocationVec &Locations, LiveOutVec &LiveOuts);
379
380 /// Create a live-out register record for the given register @p Reg.
381 LiveOutReg createLiveOutReg(unsigned Reg,
382 const TargetRegisterInfo *TRI) const;
383
384 /// Parse the register live-out mask and return a vector of live-out
385 /// registers that need to be recorded in the stackmap.
386 LiveOutVec parseRegisterLiveOutMask(const uint32_t *Mask) const;
387
388 /// Record the locations of the operands of the provided instruction in a
389 /// record keyed by the provided label. For instructions w/AnyReg calling
390 /// convention the return register is also recorded if requested. For
391 /// STACKMAP, and PATCHPOINT the label is expected to immediately *preceed*
392 /// lowering of the MI to MCInsts. For STATEPOINT, it expected to
393 /// immediately *follow*. It's not clear this difference was intentional,
394 /// but it exists today.
395 void recordStackMapOpers(const MCSymbol &L,
396 const MachineInstr &MI, uint64_t ID,
399 bool recordResult = false);
400
401 /// Emit the stackmap header.
402 void emitStackmapHeader(MCStreamer &OS);
403
404 /// Emit the function frame record for each function.
405 void emitFunctionFrameRecords(MCStreamer &OS);
406
407 /// Emit the constant pool.
408 void emitConstantPoolEntries(MCStreamer &OS);
409
410 /// Emit the callsite info for each stackmap/patchpoint intrinsic call.
411 void emitCallsiteEntries(MCStreamer &OS);
412
413 void print(raw_ostream &OS);
414 void debug() { print(dbgs()); }
415};
416
417} // end namespace llvm
418
419#endif // LLVM_CODEGEN_STACKMAPS_H
IRTranslator LLVM IR MI
unsigned const TargetRegisterInfo * TRI
unsigned Reg
This file implements a map that provides insertion order iteration.
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
raw_pwrite_stream & OS
This file defines the SmallVector class.
This class is intended to be used as a driving class for all asm writers.
Definition: AsmPrinter.h:84
Base class for the full range of assembler expressions which are needed for parsing.
Definition: MCExpr.h:35
Streaming machine code generation interface.
Definition: MCStreamer.h:212
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:40
Representation of each machine instruction.
Definition: MachineInstr.h:69
MachineOperand class - Representation of each machine instruction operand.
int64_t getImm() const
void clear()
Definition: MapVector.h:88
MI-level patchpoint operands.
Definition: StackMaps.h:76
uint32_t getNumCallArgs() const
Return the number of call arguments.
Definition: StackMaps.h:121
PatchPointOpers(const MachineInstr *MI)
Definition: StackMaps.cpp:62
unsigned getNextScratchIdx(unsigned StartIdx=0) const
Get the next scratch register operand index.
Definition: StackMaps.cpp:77
unsigned getArgIdx() const
Definition: StackMaps.h:118
uint64_t getID() const
Return the ID for the given patchpoint.
Definition: StackMaps.h:101
bool isAnyReg() const
Definition: StackMaps.h:97
uint32_t getNumPatchBytes() const
Return the number of patchable bytes the given patchpoint should emit.
Definition: StackMaps.h:104
CallingConv::ID getCallingConv() const
Returns the calling convention.
Definition: StackMaps.h:114
const MachineOperand & getCallTarget() const
Returns the target of the underlying call.
Definition: StackMaps.h:109
unsigned getStackMapStartIdx() const
Get the index at which stack map locations will be recorded.
Definition: StackMaps.h:133
unsigned getVarIdx() const
Get the operand index of the variable list of non-argument operands.
Definition: StackMaps.h:127
bool hasDef() const
Definition: StackMaps.h:98
Wrapper class representing virtual and physical registers.
Definition: Register.h:19
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: SmallVector.h:586
MI-level stackmap operands.
Definition: StackMaps.h:35
uint32_t getNumPatchBytes() const
Return the number of patchable bytes the given stackmap should emit.
Definition: StackMaps.h:50
uint64_t getID() const
Return the ID for the given stackmap.
Definition: StackMaps.h:47
unsigned getVarIdx() const
Get the operand index of the variable list of non-argument operands.
Definition: StackMaps.h:56
static unsigned getNextMetaArgIdx(const MachineInstr *MI, unsigned CurIdx)
Get index of next meta operand.
Definition: StackMaps.cpp:171
enum { DirectMemRefOp, IndirectMemRefOp, ConstantOp } OpType
Definition: StackMaps.h:293
void serializeToStackMapSection()
If there is any stack map data, create a stack map section and serialize the map info into it.
Definition: StackMaps.cpp:722
SmallVector< LiveOutReg, 8 > LiveOutVec
Definition: StackMaps.h:308
MapVector< const MCSymbol *, FunctionInfo > FnInfoMap
Definition: StackMaps.h:332
SmallVector< Location, 8 > LocationVec
Definition: StackMaps.h:307
void recordStatepoint(const MCSymbol &L, const MachineInstr &MI)
Generate a stackmap record for a statepoint instruction.
Definition: StackMaps.cpp:569
std::vector< CallsiteInfo > CallsiteInfoList
Definition: StackMaps.h:333
void recordPatchPoint(const MCSymbol &L, const MachineInstr &MI)
Generate a stackmap record for a patchpoint instruction.
Definition: StackMaps.cpp:548
FnInfoMap & getFnInfos()
Get function info.
Definition: StackMaps.h:358
CallsiteInfoList & getCSInfos()
Get call site info.
Definition: StackMaps.h:355
void recordStackMap(const MCSymbol &L, const MachineInstr &MI)
Generate a stackmap record for a stackmap instruction.
Definition: StackMaps.cpp:538
MI-level Statepoint operands.
Definition: StackMaps.h:158
StatepointOpers(const MachineInstr *MI)
Definition: StackMaps.h:173
uint32_t getNumPatchBytes() const
Return the number of patchable bytes the given statepoint should emit.
Definition: StackMaps.h:207
unsigned getIDPos() const
Get index of statepoint ID operand.
Definition: StackMaps.h:178
CallingConv::ID getCallingConv() const
Return the calling convention.
Definition: StackMaps.h:217
unsigned getCCIdx() const
Get index of Calling Convention operand.
Definition: StackMaps.h:193
unsigned getGCPointerMap(SmallVectorImpl< std::pair< unsigned, unsigned > > &GCMap)
Get vector of base/derived pairs from statepoint.
Definition: StackMaps.cpp:135
unsigned getNCallArgsPos() const
Get index of Num Call Arguments operand.
Definition: StackMaps.h:184
unsigned getNumAllocaIdx()
Get index of number of gc allocas.
Definition: StackMaps.cpp:104
unsigned getNumGcMapEntriesIdx()
Get index of number of gc map entries.
Definition: StackMaps.cpp:94
int getFirstGCPtrIdx()
Get index of first GC pointer operand of -1 if there are none.
Definition: StackMaps.cpp:125
const MachineOperand & getCallTarget() const
Return the target of the underlying call.
Definition: StackMaps.h:212
unsigned getNumDeoptArgsIdx() const
Get index of Number Deopt Arguments operand.
Definition: StackMaps.h:199
unsigned getNBytesPos() const
Get index of Num Patch Bytes operand.
Definition: StackMaps.h:181
uint64_t getNumDeoptArgs() const
Definition: StackMaps.h:224
uint64_t getFlags() const
Return the statepoint flags.
Definition: StackMaps.h:222
unsigned getFlagsIdx() const
Get index of Flags operand.
Definition: StackMaps.h:196
uint64_t getID() const
Return the ID for the given statepoint.
Definition: StackMaps.h:204
bool isFoldableReg(Register Reg) const
Return true if Reg is used only in operands which can be folded to stack usage.
Definition: StackMaps.cpp:149
unsigned getVarIdx() const
Get starting index of non call related arguments (calling convention, statepoint flags,...
Definition: StackMaps.h:188
unsigned getNumGCPtrIdx()
Get index of number of GC pointers.
Definition: StackMaps.cpp:114
TargetRegisterInfo base class - We assume that the target defines a static array of TargetRegisterDes...
The instances of the Type class are immutable: once they are created, they are never changed.
Definition: Type.h:45
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
@ AnyReg
OBSOLETED - Used for stack based JavaScript calls.
Definition: CallingConv.h:60
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:163
OutputIt move(R &&Range, OutputIt Out)
Provide wrappers to std::move which take ranges instead of having to pass begin/end explicitly.
Definition: STLExtras.h:1858
Implement std::hash so that hash_code can be used in STL containers.
Definition: BitVector.h:858
CallsiteInfo(const MCExpr *CSOffsetExpr, uint64_t ID, LocationVec &&Locations, LiveOutVec &&LiveOuts)
Definition: StackMaps.h:326
const MCExpr * CSOffsetExpr
Definition: StackMaps.h:320
FunctionInfo(uint64_t StackSize)
Definition: StackMaps.h:316
LiveOutReg(uint16_t Reg, uint16_t DwarfRegNum, uint16_t Size)
Definition: StackMaps.h:286
Location(LocationType Type, uint16_t Size, uint16_t Reg, int32_t Offset)
Definition: StackMaps.h:276