File: | llvm/lib/CodeGen/LiveDebugValues.cpp |
Warning: | line 1752, column 9 Value stored to 'MBBJoined' is never read |
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1 | //===- LiveDebugValues.cpp - Tracking Debug Value MIs ---------------------===// |
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 pass implements a data flow analysis that propagates debug location |
10 | /// information by inserting additional DBG_VALUE insts into the machine |
11 | /// instruction stream. Before running, each DBG_VALUE inst corresponds to a |
12 | /// source assignment of a variable. Afterwards, a DBG_VALUE inst specifies a |
13 | /// variable location for the current basic block (see SourceLevelDebugging.rst). |
14 | /// |
15 | /// This is a separate pass from DbgValueHistoryCalculator to facilitate |
16 | /// testing and improve modularity. |
17 | /// |
18 | /// Each variable location is represented by a VarLoc object that identifies the |
19 | /// source variable, its current machine-location, and the DBG_VALUE inst that |
20 | /// specifies the location. Each VarLoc is indexed in the (function-scope) |
21 | /// VarLocMap, giving each VarLoc a unique index. Rather than operate directly |
22 | /// on machine locations, the dataflow analysis in this pass identifies |
23 | /// locations by their index in the VarLocMap, meaning all the variable |
24 | /// locations in a block can be described by a sparse vector of VarLocMap |
25 | /// indexes. |
26 | /// |
27 | //===----------------------------------------------------------------------===// |
28 | |
29 | #include "llvm/ADT/CoalescingBitVector.h" |
30 | #include "llvm/ADT/DenseMap.h" |
31 | #include "llvm/ADT/PostOrderIterator.h" |
32 | #include "llvm/ADT/SmallPtrSet.h" |
33 | #include "llvm/ADT/SmallSet.h" |
34 | #include "llvm/ADT/SmallVector.h" |
35 | #include "llvm/ADT/Statistic.h" |
36 | #include "llvm/ADT/UniqueVector.h" |
37 | #include "llvm/CodeGen/LexicalScopes.h" |
38 | #include "llvm/CodeGen/MachineBasicBlock.h" |
39 | #include "llvm/CodeGen/MachineFrameInfo.h" |
40 | #include "llvm/CodeGen/MachineFunction.h" |
41 | #include "llvm/CodeGen/MachineFunctionPass.h" |
42 | #include "llvm/CodeGen/MachineInstr.h" |
43 | #include "llvm/CodeGen/MachineInstrBuilder.h" |
44 | #include "llvm/CodeGen/MachineMemOperand.h" |
45 | #include "llvm/CodeGen/MachineOperand.h" |
46 | #include "llvm/CodeGen/PseudoSourceValue.h" |
47 | #include "llvm/CodeGen/RegisterScavenging.h" |
48 | #include "llvm/CodeGen/TargetFrameLowering.h" |
49 | #include "llvm/CodeGen/TargetInstrInfo.h" |
50 | #include "llvm/CodeGen/TargetLowering.h" |
51 | #include "llvm/CodeGen/TargetPassConfig.h" |
52 | #include "llvm/CodeGen/TargetRegisterInfo.h" |
53 | #include "llvm/CodeGen/TargetSubtargetInfo.h" |
54 | #include "llvm/Config/llvm-config.h" |
55 | #include "llvm/IR/DIBuilder.h" |
56 | #include "llvm/IR/DebugInfoMetadata.h" |
57 | #include "llvm/IR/DebugLoc.h" |
58 | #include "llvm/IR/Function.h" |
59 | #include "llvm/IR/Module.h" |
60 | #include "llvm/InitializePasses.h" |
61 | #include "llvm/MC/MCRegisterInfo.h" |
62 | #include "llvm/Pass.h" |
63 | #include "llvm/Support/Casting.h" |
64 | #include "llvm/Support/Compiler.h" |
65 | #include "llvm/Support/Debug.h" |
66 | #include "llvm/Support/raw_ostream.h" |
67 | #include <algorithm> |
68 | #include <cassert> |
69 | #include <cstdint> |
70 | #include <functional> |
71 | #include <queue> |
72 | #include <tuple> |
73 | #include <utility> |
74 | #include <vector> |
75 | |
76 | using namespace llvm; |
77 | |
78 | #define DEBUG_TYPE"livedebugvalues" "livedebugvalues" |
79 | |
80 | STATISTIC(NumInserted, "Number of DBG_VALUE instructions inserted")static llvm::Statistic NumInserted = {"livedebugvalues", "NumInserted" , "Number of DBG_VALUE instructions inserted"}; |
81 | STATISTIC(NumRemoved, "Number of DBG_VALUE instructions removed")static llvm::Statistic NumRemoved = {"livedebugvalues", "NumRemoved" , "Number of DBG_VALUE instructions removed"}; |
82 | |
83 | // If @MI is a DBG_VALUE with debug value described by a defined |
84 | // register, returns the number of this register. In the other case, returns 0. |
85 | static Register isDbgValueDescribedByReg(const MachineInstr &MI) { |
86 | assert(MI.isDebugValue() && "expected a DBG_VALUE")((MI.isDebugValue() && "expected a DBG_VALUE") ? static_cast <void> (0) : __assert_fail ("MI.isDebugValue() && \"expected a DBG_VALUE\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 86, __PRETTY_FUNCTION__)); |
87 | assert(MI.getNumOperands() == 4 && "malformed DBG_VALUE")((MI.getNumOperands() == 4 && "malformed DBG_VALUE") ? static_cast<void> (0) : __assert_fail ("MI.getNumOperands() == 4 && \"malformed DBG_VALUE\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 87, __PRETTY_FUNCTION__)); |
88 | // If location of variable is described using a register (directly |
89 | // or indirectly), this register is always a first operand. |
90 | return MI.getOperand(0).isReg() ? MI.getOperand(0).getReg() : Register(); |
91 | } |
92 | |
93 | /// If \p Op is a stack or frame register return true, otherwise return false. |
94 | /// This is used to avoid basing the debug entry values on the registers, since |
95 | /// we do not support it at the moment. |
96 | static bool isRegOtherThanSPAndFP(const MachineOperand &Op, |
97 | const MachineInstr &MI, |
98 | const TargetRegisterInfo *TRI) { |
99 | if (!Op.isReg()) |
100 | return false; |
101 | |
102 | const MachineFunction *MF = MI.getParent()->getParent(); |
103 | const TargetLowering *TLI = MF->getSubtarget().getTargetLowering(); |
104 | unsigned SP = TLI->getStackPointerRegisterToSaveRestore(); |
105 | Register FP = TRI->getFrameRegister(*MF); |
106 | Register Reg = Op.getReg(); |
107 | |
108 | return Reg && Reg != SP && Reg != FP; |
109 | } |
110 | |
111 | namespace { |
112 | |
113 | using DefinedRegsSet = SmallSet<Register, 32>; |
114 | using VarLocSet = CoalescingBitVector<uint64_t>; |
115 | |
116 | /// A type-checked pair of {Register Location (or 0), Index}, used to index |
117 | /// into a \ref VarLocMap. This can be efficiently converted to a 64-bit int |
118 | /// for insertion into a \ref VarLocSet, and efficiently converted back. The |
119 | /// type-checker helps ensure that the conversions aren't lossy. |
120 | /// |
121 | /// Why encode a location /into/ the VarLocMap index? This makes it possible |
122 | /// to find the open VarLocs killed by a register def very quickly. This is a |
123 | /// performance-critical operation for LiveDebugValues. |
124 | /// |
125 | /// TODO: Consider adding reserved intervals for kinds of VarLocs other than |
126 | /// RegisterKind, like SpillLocKind or EntryValueKind, to optimize iteration |
127 | /// over open locations. |
128 | struct LocIndex { |
129 | uint32_t Location; // Physical registers live in the range [1;2^30) (see |
130 | // \ref MCRegister), so we have plenty of range left here |
131 | // to encode non-register locations. |
132 | uint32_t Index; |
133 | |
134 | LocIndex(uint32_t Location, uint32_t Index) |
135 | : Location(Location), Index(Index) {} |
136 | |
137 | uint64_t getAsRawInteger() const { |
138 | return (static_cast<uint64_t>(Location) << 32) | Index; |
139 | } |
140 | |
141 | template<typename IntT> static LocIndex fromRawInteger(IntT ID) { |
142 | static_assert(std::is_unsigned<IntT>::value && |
143 | sizeof(ID) == sizeof(uint64_t), |
144 | "Cannot convert raw integer to LocIndex"); |
145 | return {static_cast<uint32_t>(ID >> 32), static_cast<uint32_t>(ID)}; |
146 | } |
147 | |
148 | /// Get the start of the interval reserved for VarLocs of kind RegisterKind |
149 | /// which reside in \p Reg. The end is at rawIndexForReg(Reg+1)-1. |
150 | static uint64_t rawIndexForReg(uint32_t Reg) { |
151 | return LocIndex(Reg, 0).getAsRawInteger(); |
152 | } |
153 | }; |
154 | |
155 | class LiveDebugValues : public MachineFunctionPass { |
156 | private: |
157 | const TargetRegisterInfo *TRI; |
158 | const TargetInstrInfo *TII; |
159 | const TargetFrameLowering *TFI; |
160 | BitVector CalleeSavedRegs; |
161 | LexicalScopes LS; |
162 | VarLocSet::Allocator Alloc; |
163 | |
164 | enum struct TransferKind { TransferCopy, TransferSpill, TransferRestore }; |
165 | |
166 | /// Keeps track of lexical scopes associated with a user value's source |
167 | /// location. |
168 | class UserValueScopes { |
169 | DebugLoc DL; |
170 | LexicalScopes &LS; |
171 | SmallPtrSet<const MachineBasicBlock *, 4> LBlocks; |
172 | |
173 | public: |
174 | UserValueScopes(DebugLoc D, LexicalScopes &L) : DL(std::move(D)), LS(L) {} |
175 | |
176 | /// Return true if current scope dominates at least one machine |
177 | /// instruction in a given machine basic block. |
178 | bool dominates(MachineBasicBlock *MBB) { |
179 | if (LBlocks.empty()) |
180 | LS.getMachineBasicBlocks(DL, LBlocks); |
181 | return LBlocks.count(MBB) != 0 || LS.dominates(DL, MBB); |
182 | } |
183 | }; |
184 | |
185 | using FragmentInfo = DIExpression::FragmentInfo; |
186 | using OptFragmentInfo = Optional<DIExpression::FragmentInfo>; |
187 | |
188 | /// A pair of debug variable and value location. |
189 | struct VarLoc { |
190 | // The location at which a spilled variable resides. It consists of a |
191 | // register and an offset. |
192 | struct SpillLoc { |
193 | unsigned SpillBase; |
194 | int SpillOffset; |
195 | bool operator==(const SpillLoc &Other) const { |
196 | return SpillBase == Other.SpillBase && SpillOffset == Other.SpillOffset; |
197 | } |
198 | }; |
199 | |
200 | /// Identity of the variable at this location. |
201 | const DebugVariable Var; |
202 | |
203 | /// The expression applied to this location. |
204 | const DIExpression *Expr; |
205 | |
206 | /// DBG_VALUE to clone var/expr information from if this location |
207 | /// is moved. |
208 | const MachineInstr &MI; |
209 | |
210 | mutable UserValueScopes UVS; |
211 | enum VarLocKind { |
212 | InvalidKind = 0, |
213 | RegisterKind, |
214 | SpillLocKind, |
215 | ImmediateKind, |
216 | EntryValueKind, |
217 | EntryValueBackupKind, |
218 | EntryValueCopyBackupKind |
219 | } Kind = InvalidKind; |
220 | |
221 | /// The value location. Stored separately to avoid repeatedly |
222 | /// extracting it from MI. |
223 | union { |
224 | uint64_t RegNo; |
225 | SpillLoc SpillLocation; |
226 | uint64_t Hash; |
227 | int64_t Immediate; |
228 | const ConstantFP *FPImm; |
229 | const ConstantInt *CImm; |
230 | } Loc; |
231 | |
232 | VarLoc(const MachineInstr &MI, LexicalScopes &LS) |
233 | : Var(MI.getDebugVariable(), MI.getDebugExpression(), |
234 | MI.getDebugLoc()->getInlinedAt()), |
235 | Expr(MI.getDebugExpression()), MI(MI), UVS(MI.getDebugLoc(), LS) { |
236 | static_assert((sizeof(Loc) == sizeof(uint64_t)), |
237 | "hash does not cover all members of Loc"); |
238 | assert(MI.isDebugValue() && "not a DBG_VALUE")((MI.isDebugValue() && "not a DBG_VALUE") ? static_cast <void> (0) : __assert_fail ("MI.isDebugValue() && \"not a DBG_VALUE\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 238, __PRETTY_FUNCTION__)); |
239 | assert(MI.getNumOperands() == 4 && "malformed DBG_VALUE")((MI.getNumOperands() == 4 && "malformed DBG_VALUE") ? static_cast<void> (0) : __assert_fail ("MI.getNumOperands() == 4 && \"malformed DBG_VALUE\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 239, __PRETTY_FUNCTION__)); |
240 | if (int RegNo = isDbgValueDescribedByReg(MI)) { |
241 | Kind = RegisterKind; |
242 | Loc.RegNo = RegNo; |
243 | } else if (MI.getOperand(0).isImm()) { |
244 | Kind = ImmediateKind; |
245 | Loc.Immediate = MI.getOperand(0).getImm(); |
246 | } else if (MI.getOperand(0).isFPImm()) { |
247 | Kind = ImmediateKind; |
248 | Loc.FPImm = MI.getOperand(0).getFPImm(); |
249 | } else if (MI.getOperand(0).isCImm()) { |
250 | Kind = ImmediateKind; |
251 | Loc.CImm = MI.getOperand(0).getCImm(); |
252 | } |
253 | |
254 | // We create the debug entry values from the factory functions rather than |
255 | // from this ctor. |
256 | assert(Kind != EntryValueKind && !isEntryBackupLoc())((Kind != EntryValueKind && !isEntryBackupLoc()) ? static_cast <void> (0) : __assert_fail ("Kind != EntryValueKind && !isEntryBackupLoc()" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 256, __PRETTY_FUNCTION__)); |
257 | } |
258 | |
259 | /// Take the variable and machine-location in DBG_VALUE MI, and build an |
260 | /// entry location using the given expression. |
261 | static VarLoc CreateEntryLoc(const MachineInstr &MI, LexicalScopes &LS, |
262 | const DIExpression *EntryExpr, unsigned Reg) { |
263 | VarLoc VL(MI, LS); |
264 | assert(VL.Kind == RegisterKind)((VL.Kind == RegisterKind) ? static_cast<void> (0) : __assert_fail ("VL.Kind == RegisterKind", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 264, __PRETTY_FUNCTION__)); |
265 | VL.Kind = EntryValueKind; |
266 | VL.Expr = EntryExpr; |
267 | VL.Loc.RegNo = Reg; |
268 | return VL; |
269 | } |
270 | |
271 | /// Take the variable and machine-location from the DBG_VALUE (from the |
272 | /// function entry), and build an entry value backup location. The backup |
273 | /// location will turn into the normal location if the backup is valid at |
274 | /// the time of the primary location clobbering. |
275 | static VarLoc CreateEntryBackupLoc(const MachineInstr &MI, |
276 | LexicalScopes &LS, |
277 | const DIExpression *EntryExpr) { |
278 | VarLoc VL(MI, LS); |
279 | assert(VL.Kind == RegisterKind)((VL.Kind == RegisterKind) ? static_cast<void> (0) : __assert_fail ("VL.Kind == RegisterKind", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 279, __PRETTY_FUNCTION__)); |
280 | VL.Kind = EntryValueBackupKind; |
281 | VL.Expr = EntryExpr; |
282 | return VL; |
283 | } |
284 | |
285 | /// Take the variable and machine-location from the DBG_VALUE (from the |
286 | /// function entry), and build a copy of an entry value backup location by |
287 | /// setting the register location to NewReg. |
288 | static VarLoc CreateEntryCopyBackupLoc(const MachineInstr &MI, |
289 | LexicalScopes &LS, |
290 | const DIExpression *EntryExpr, |
291 | unsigned NewReg) { |
292 | VarLoc VL(MI, LS); |
293 | assert(VL.Kind == RegisterKind)((VL.Kind == RegisterKind) ? static_cast<void> (0) : __assert_fail ("VL.Kind == RegisterKind", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 293, __PRETTY_FUNCTION__)); |
294 | VL.Kind = EntryValueCopyBackupKind; |
295 | VL.Expr = EntryExpr; |
296 | VL.Loc.RegNo = NewReg; |
297 | return VL; |
298 | } |
299 | |
300 | /// Copy the register location in DBG_VALUE MI, updating the register to |
301 | /// be NewReg. |
302 | static VarLoc CreateCopyLoc(const MachineInstr &MI, LexicalScopes &LS, |
303 | unsigned NewReg) { |
304 | VarLoc VL(MI, LS); |
305 | assert(VL.Kind == RegisterKind)((VL.Kind == RegisterKind) ? static_cast<void> (0) : __assert_fail ("VL.Kind == RegisterKind", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 305, __PRETTY_FUNCTION__)); |
306 | VL.Loc.RegNo = NewReg; |
307 | return VL; |
308 | } |
309 | |
310 | /// Take the variable described by DBG_VALUE MI, and create a VarLoc |
311 | /// locating it in the specified spill location. |
312 | static VarLoc CreateSpillLoc(const MachineInstr &MI, unsigned SpillBase, |
313 | int SpillOffset, LexicalScopes &LS) { |
314 | VarLoc VL(MI, LS); |
315 | assert(VL.Kind == RegisterKind)((VL.Kind == RegisterKind) ? static_cast<void> (0) : __assert_fail ("VL.Kind == RegisterKind", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 315, __PRETTY_FUNCTION__)); |
316 | VL.Kind = SpillLocKind; |
317 | VL.Loc.SpillLocation = {SpillBase, SpillOffset}; |
318 | return VL; |
319 | } |
320 | |
321 | /// Create a DBG_VALUE representing this VarLoc in the given function. |
322 | /// Copies variable-specific information such as DILocalVariable and |
323 | /// inlining information from the original DBG_VALUE instruction, which may |
324 | /// have been several transfers ago. |
325 | MachineInstr *BuildDbgValue(MachineFunction &MF) const { |
326 | const DebugLoc &DbgLoc = MI.getDebugLoc(); |
327 | bool Indirect = MI.isIndirectDebugValue(); |
328 | const auto &IID = MI.getDesc(); |
329 | const DILocalVariable *Var = MI.getDebugVariable(); |
330 | const DIExpression *DIExpr = MI.getDebugExpression(); |
331 | |
332 | switch (Kind) { |
333 | case EntryValueKind: |
334 | // An entry value is a register location -- but with an updated |
335 | // expression. The register location of such DBG_VALUE is always the one |
336 | // from the entry DBG_VALUE, it does not matter if the entry value was |
337 | // copied in to another register due to some optimizations. |
338 | return BuildMI(MF, DbgLoc, IID, Indirect, MI.getOperand(0).getReg(), |
339 | Var, Expr); |
340 | case RegisterKind: |
341 | // Register locations are like the source DBG_VALUE, but with the |
342 | // register number from this VarLoc. |
343 | return BuildMI(MF, DbgLoc, IID, Indirect, Loc.RegNo, Var, DIExpr); |
344 | case SpillLocKind: { |
345 | // Spills are indirect DBG_VALUEs, with a base register and offset. |
346 | // Use the original DBG_VALUEs expression to build the spilt location |
347 | // on top of. FIXME: spill locations created before this pass runs |
348 | // are not recognized, and not handled here. |
349 | auto *SpillExpr = DIExpression::prepend( |
350 | DIExpr, DIExpression::ApplyOffset, Loc.SpillLocation.SpillOffset); |
351 | unsigned Base = Loc.SpillLocation.SpillBase; |
352 | return BuildMI(MF, DbgLoc, IID, true, Base, Var, SpillExpr); |
353 | } |
354 | case ImmediateKind: { |
355 | MachineOperand MO = MI.getOperand(0); |
356 | return BuildMI(MF, DbgLoc, IID, Indirect, MO, Var, DIExpr); |
357 | } |
358 | case EntryValueBackupKind: |
359 | case EntryValueCopyBackupKind: |
360 | case InvalidKind: |
361 | llvm_unreachable(::llvm::llvm_unreachable_internal("Tried to produce DBG_VALUE for invalid or backup VarLoc" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 362) |
362 | "Tried to produce DBG_VALUE for invalid or backup VarLoc")::llvm::llvm_unreachable_internal("Tried to produce DBG_VALUE for invalid or backup VarLoc" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 362); |
363 | } |
364 | llvm_unreachable("Unrecognized LiveDebugValues.VarLoc.Kind enum")::llvm::llvm_unreachable_internal("Unrecognized LiveDebugValues.VarLoc.Kind enum" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 364); |
365 | } |
366 | |
367 | /// Is the Loc field a constant or constant object? |
368 | bool isConstant() const { return Kind == ImmediateKind; } |
369 | |
370 | /// Check if the Loc field is an entry backup location. |
371 | bool isEntryBackupLoc() const { |
372 | return Kind == EntryValueBackupKind || Kind == EntryValueCopyBackupKind; |
373 | } |
374 | |
375 | /// If this variable is described by a register holding the entry value, |
376 | /// return it, otherwise return 0. |
377 | unsigned getEntryValueBackupReg() const { |
378 | if (Kind == EntryValueBackupKind) |
379 | return Loc.RegNo; |
380 | return 0; |
381 | } |
382 | |
383 | /// If this variable is described by a register holding the copy of the |
384 | /// entry value, return it, otherwise return 0. |
385 | unsigned getEntryValueCopyBackupReg() const { |
386 | if (Kind == EntryValueCopyBackupKind) |
387 | return Loc.RegNo; |
388 | return 0; |
389 | } |
390 | |
391 | /// If this variable is described by a register, return it, |
392 | /// otherwise return 0. |
393 | unsigned isDescribedByReg() const { |
394 | if (Kind == RegisterKind) |
395 | return Loc.RegNo; |
396 | return 0; |
397 | } |
398 | |
399 | /// Determine whether the lexical scope of this value's debug location |
400 | /// dominates MBB. |
401 | bool dominates(MachineBasicBlock &MBB) const { return UVS.dominates(&MBB); } |
402 | |
403 | #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) |
404 | // TRI can be null. |
405 | void dump(const TargetRegisterInfo *TRI, raw_ostream &Out = dbgs()) const { |
406 | dbgs() << "VarLoc("; |
407 | switch (Kind) { |
408 | case RegisterKind: |
409 | case EntryValueKind: |
410 | case EntryValueBackupKind: |
411 | case EntryValueCopyBackupKind: |
412 | dbgs() << printReg(Loc.RegNo, TRI); |
413 | break; |
414 | case SpillLocKind: |
415 | dbgs() << printReg(Loc.SpillLocation.SpillBase, TRI); |
416 | dbgs() << "[" << Loc.SpillLocation.SpillOffset << "]"; |
417 | break; |
418 | case ImmediateKind: |
419 | dbgs() << Loc.Immediate; |
420 | break; |
421 | case InvalidKind: |
422 | llvm_unreachable("Invalid VarLoc in dump method")::llvm::llvm_unreachable_internal("Invalid VarLoc in dump method" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 422); |
423 | } |
424 | |
425 | dbgs() << ", \"" << Var.getVariable()->getName() << "\", " << *Expr |
426 | << ", "; |
427 | if (Var.getInlinedAt()) |
428 | dbgs() << "!" << Var.getInlinedAt()->getMetadataID() << ")\n"; |
429 | else |
430 | dbgs() << "(null))"; |
431 | |
432 | if (isEntryBackupLoc()) |
433 | dbgs() << " (backup loc)\n"; |
434 | else |
435 | dbgs() << "\n"; |
436 | } |
437 | #endif |
438 | |
439 | bool operator==(const VarLoc &Other) const { |
440 | return Kind == Other.Kind && Var == Other.Var && |
441 | Loc.Hash == Other.Loc.Hash && Expr == Other.Expr; |
442 | } |
443 | |
444 | /// This operator guarantees that VarLocs are sorted by Variable first. |
445 | bool operator<(const VarLoc &Other) const { |
446 | return std::tie(Var, Kind, Loc.Hash, Expr) < |
447 | std::tie(Other.Var, Other.Kind, Other.Loc.Hash, Other.Expr); |
448 | } |
449 | }; |
450 | |
451 | /// VarLocMap is used for two things: |
452 | /// 1) Assigning a unique LocIndex to a VarLoc. This LocIndex can be used to |
453 | /// virtually insert a VarLoc into a VarLocSet. |
454 | /// 2) Given a LocIndex, look up the unique associated VarLoc. |
455 | class VarLocMap { |
456 | /// Map a VarLoc to an index within the vector reserved for its location |
457 | /// within Loc2Vars. |
458 | std::map<VarLoc, uint32_t> Var2Index; |
459 | |
460 | /// Map a location to a vector which holds VarLocs which live in that |
461 | /// location. |
462 | SmallDenseMap<uint32_t, std::vector<VarLoc>> Loc2Vars; |
463 | |
464 | public: |
465 | /// Retrieve a unique LocIndex for \p VL. |
466 | LocIndex insert(const VarLoc &VL) { |
467 | uint32_t Location = VL.isDescribedByReg(); |
468 | uint32_t &Index = Var2Index[VL]; |
469 | if (!Index) { |
470 | auto &Vars = Loc2Vars[Location]; |
471 | Vars.push_back(VL); |
472 | Index = Vars.size(); |
473 | } |
474 | return {Location, Index - 1}; |
475 | } |
476 | |
477 | /// Retrieve the unique VarLoc associated with \p ID. |
478 | const VarLoc &operator[](LocIndex ID) const { |
479 | auto LocIt = Loc2Vars.find(ID.Location); |
480 | assert(LocIt != Loc2Vars.end() && "Location not tracked")((LocIt != Loc2Vars.end() && "Location not tracked") ? static_cast<void> (0) : __assert_fail ("LocIt != Loc2Vars.end() && \"Location not tracked\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 480, __PRETTY_FUNCTION__)); |
481 | return LocIt->second[ID.Index]; |
482 | } |
483 | }; |
484 | |
485 | using VarLocInMBB = SmallDenseMap<const MachineBasicBlock *, VarLocSet>; |
486 | struct TransferDebugPair { |
487 | MachineInstr *TransferInst; ///< Instruction where this transfer occurs. |
488 | LocIndex LocationID; ///< Location number for the transfer dest. |
489 | }; |
490 | using TransferMap = SmallVector<TransferDebugPair, 4>; |
491 | |
492 | // Types for recording sets of variable fragments that overlap. For a given |
493 | // local variable, we record all other fragments of that variable that could |
494 | // overlap it, to reduce search time. |
495 | using FragmentOfVar = |
496 | std::pair<const DILocalVariable *, DIExpression::FragmentInfo>; |
497 | using OverlapMap = |
498 | DenseMap<FragmentOfVar, SmallVector<DIExpression::FragmentInfo, 1>>; |
499 | |
500 | // Helper while building OverlapMap, a map of all fragments seen for a given |
501 | // DILocalVariable. |
502 | using VarToFragments = |
503 | DenseMap<const DILocalVariable *, SmallSet<FragmentInfo, 4>>; |
504 | |
505 | /// This holds the working set of currently open ranges. For fast |
506 | /// access, this is done both as a set of VarLocIDs, and a map of |
507 | /// DebugVariable to recent VarLocID. Note that a DBG_VALUE ends all |
508 | /// previous open ranges for the same variable. In addition, we keep |
509 | /// two different maps (Vars/EntryValuesBackupVars), so erase/insert |
510 | /// methods act differently depending on whether a VarLoc is primary |
511 | /// location or backup one. In the case the VarLoc is backup location |
512 | /// we will erase/insert from the EntryValuesBackupVars map, otherwise |
513 | /// we perform the operation on the Vars. |
514 | class OpenRangesSet { |
515 | VarLocSet VarLocs; |
516 | // Map the DebugVariable to recent primary location ID. |
517 | SmallDenseMap<DebugVariable, LocIndex, 8> Vars; |
518 | // Map the DebugVariable to recent backup location ID. |
519 | SmallDenseMap<DebugVariable, LocIndex, 8> EntryValuesBackupVars; |
520 | OverlapMap &OverlappingFragments; |
521 | |
522 | public: |
523 | OpenRangesSet(VarLocSet::Allocator &Alloc, OverlapMap &_OLapMap) |
524 | : VarLocs(Alloc), OverlappingFragments(_OLapMap) {} |
525 | |
526 | const VarLocSet &getVarLocs() const { return VarLocs; } |
527 | |
528 | /// Terminate all open ranges for VL.Var by removing it from the set. |
529 | void erase(const VarLoc &VL); |
530 | |
531 | /// Terminate all open ranges listed in \c KillSet by removing |
532 | /// them from the set. |
533 | void erase(const VarLocSet &KillSet, const VarLocMap &VarLocIDs); |
534 | |
535 | /// Insert a new range into the set. |
536 | void insert(LocIndex VarLocID, const VarLoc &VL); |
537 | |
538 | /// Insert a set of ranges. |
539 | void insertFromLocSet(const VarLocSet &ToLoad, const VarLocMap &Map) { |
540 | for (uint64_t ID : ToLoad) { |
541 | LocIndex Idx = LocIndex::fromRawInteger(ID); |
542 | const VarLoc &VarL = Map[Idx]; |
543 | insert(Idx, VarL); |
544 | } |
545 | } |
546 | |
547 | llvm::Optional<LocIndex> getEntryValueBackup(DebugVariable Var); |
548 | |
549 | /// Empty the set. |
550 | void clear() { |
551 | VarLocs.clear(); |
552 | Vars.clear(); |
553 | EntryValuesBackupVars.clear(); |
554 | } |
555 | |
556 | /// Return whether the set is empty or not. |
557 | bool empty() const { |
558 | assert(Vars.empty() == EntryValuesBackupVars.empty() &&((Vars.empty() == EntryValuesBackupVars.empty() && Vars .empty() == VarLocs.empty() && "open ranges are inconsistent" ) ? static_cast<void> (0) : __assert_fail ("Vars.empty() == EntryValuesBackupVars.empty() && Vars.empty() == VarLocs.empty() && \"open ranges are inconsistent\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 560, __PRETTY_FUNCTION__)) |
559 | Vars.empty() == VarLocs.empty() &&((Vars.empty() == EntryValuesBackupVars.empty() && Vars .empty() == VarLocs.empty() && "open ranges are inconsistent" ) ? static_cast<void> (0) : __assert_fail ("Vars.empty() == EntryValuesBackupVars.empty() && Vars.empty() == VarLocs.empty() && \"open ranges are inconsistent\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 560, __PRETTY_FUNCTION__)) |
560 | "open ranges are inconsistent")((Vars.empty() == EntryValuesBackupVars.empty() && Vars .empty() == VarLocs.empty() && "open ranges are inconsistent" ) ? static_cast<void> (0) : __assert_fail ("Vars.empty() == EntryValuesBackupVars.empty() && Vars.empty() == VarLocs.empty() && \"open ranges are inconsistent\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 560, __PRETTY_FUNCTION__)); |
561 | return VarLocs.empty(); |
562 | } |
563 | }; |
564 | |
565 | /// Collect all VarLoc IDs from \p CollectFrom for VarLocs which are located |
566 | /// in \p Reg, of kind RegisterKind. Insert collected IDs in \p Collected. |
567 | void collectIDsForReg(VarLocSet &Collected, uint32_t Reg, |
568 | const VarLocSet &CollectFrom) const; |
569 | |
570 | /// Get the registers which are used by VarLocs of kind RegisterKind tracked |
571 | /// by \p CollectFrom. |
572 | void getUsedRegs(const VarLocSet &CollectFrom, |
573 | SmallVectorImpl<uint32_t> &UsedRegs) const; |
574 | |
575 | VarLocSet &getVarLocsInMBB(const MachineBasicBlock *MBB, VarLocInMBB &Locs) { |
576 | auto Result = Locs.try_emplace(MBB, Alloc); |
577 | return Result.first->second; |
578 | } |
579 | |
580 | const VarLocSet &getVarLocsInMBB(const MachineBasicBlock *MBB, |
581 | const VarLocInMBB &Locs) const { |
582 | auto It = Locs.find(MBB); |
583 | assert(It != Locs.end() && "MBB not in map")((It != Locs.end() && "MBB not in map") ? static_cast <void> (0) : __assert_fail ("It != Locs.end() && \"MBB not in map\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 583, __PRETTY_FUNCTION__)); |
584 | return It->second; |
585 | } |
586 | |
587 | /// Tests whether this instruction is a spill to a stack location. |
588 | bool isSpillInstruction(const MachineInstr &MI, MachineFunction *MF); |
589 | |
590 | /// Decide if @MI is a spill instruction and return true if it is. We use 2 |
591 | /// criteria to make this decision: |
592 | /// - Is this instruction a store to a spill slot? |
593 | /// - Is there a register operand that is both used and killed? |
594 | /// TODO: Store optimization can fold spills into other stores (including |
595 | /// other spills). We do not handle this yet (more than one memory operand). |
596 | bool isLocationSpill(const MachineInstr &MI, MachineFunction *MF, |
597 | unsigned &Reg); |
598 | |
599 | /// Returns true if the given machine instruction is a debug value which we |
600 | /// can emit entry values for. |
601 | /// |
602 | /// Currently, we generate debug entry values only for parameters that are |
603 | /// unmodified throughout the function and located in a register. |
604 | bool isEntryValueCandidate(const MachineInstr &MI, |
605 | const DefinedRegsSet &Regs) const; |
606 | |
607 | /// If a given instruction is identified as a spill, return the spill location |
608 | /// and set \p Reg to the spilled register. |
609 | Optional<VarLoc::SpillLoc> isRestoreInstruction(const MachineInstr &MI, |
610 | MachineFunction *MF, |
611 | unsigned &Reg); |
612 | /// Given a spill instruction, extract the register and offset used to |
613 | /// address the spill location in a target independent way. |
614 | VarLoc::SpillLoc extractSpillBaseRegAndOffset(const MachineInstr &MI); |
615 | void insertTransferDebugPair(MachineInstr &MI, OpenRangesSet &OpenRanges, |
616 | TransferMap &Transfers, VarLocMap &VarLocIDs, |
617 | LocIndex OldVarID, TransferKind Kind, |
618 | unsigned NewReg = 0); |
619 | |
620 | void transferDebugValue(const MachineInstr &MI, OpenRangesSet &OpenRanges, |
621 | VarLocMap &VarLocIDs); |
622 | void transferSpillOrRestoreInst(MachineInstr &MI, OpenRangesSet &OpenRanges, |
623 | VarLocMap &VarLocIDs, TransferMap &Transfers); |
624 | bool removeEntryValue(const MachineInstr &MI, OpenRangesSet &OpenRanges, |
625 | VarLocMap &VarLocIDs, const VarLoc &EntryVL); |
626 | void emitEntryValues(MachineInstr &MI, OpenRangesSet &OpenRanges, |
627 | VarLocMap &VarLocIDs, TransferMap &Transfers, |
628 | VarLocSet &KillSet); |
629 | void recordEntryValue(const MachineInstr &MI, |
630 | const DefinedRegsSet &DefinedRegs, |
631 | OpenRangesSet &OpenRanges, VarLocMap &VarLocIDs); |
632 | void transferRegisterCopy(MachineInstr &MI, OpenRangesSet &OpenRanges, |
633 | VarLocMap &VarLocIDs, TransferMap &Transfers); |
634 | void transferRegisterDef(MachineInstr &MI, OpenRangesSet &OpenRanges, |
635 | VarLocMap &VarLocIDs, TransferMap &Transfers); |
636 | bool transferTerminator(MachineBasicBlock *MBB, OpenRangesSet &OpenRanges, |
637 | VarLocInMBB &OutLocs, const VarLocMap &VarLocIDs); |
638 | |
639 | void process(MachineInstr &MI, OpenRangesSet &OpenRanges, |
640 | VarLocMap &VarLocIDs, TransferMap &Transfers); |
641 | |
642 | void accumulateFragmentMap(MachineInstr &MI, VarToFragments &SeenFragments, |
643 | OverlapMap &OLapMap); |
644 | |
645 | bool join(MachineBasicBlock &MBB, VarLocInMBB &OutLocs, VarLocInMBB &InLocs, |
646 | const VarLocMap &VarLocIDs, |
647 | SmallPtrSet<const MachineBasicBlock *, 16> &Visited, |
648 | SmallPtrSetImpl<const MachineBasicBlock *> &ArtificialBlocks, |
649 | VarLocInMBB &PendingInLocs); |
650 | |
651 | /// Create DBG_VALUE insts for inlocs that have been propagated but |
652 | /// had their instruction creation deferred. |
653 | void flushPendingLocs(VarLocInMBB &PendingInLocs, VarLocMap &VarLocIDs); |
654 | |
655 | bool ExtendRanges(MachineFunction &MF); |
656 | |
657 | public: |
658 | static char ID; |
659 | |
660 | /// Default construct and initialize the pass. |
661 | LiveDebugValues(); |
662 | |
663 | /// Tell the pass manager which passes we depend on and what |
664 | /// information we preserve. |
665 | void getAnalysisUsage(AnalysisUsage &AU) const override; |
666 | |
667 | MachineFunctionProperties getRequiredProperties() const override { |
668 | return MachineFunctionProperties().set( |
669 | MachineFunctionProperties::Property::NoVRegs); |
670 | } |
671 | |
672 | /// Print to ostream with a message. |
673 | void printVarLocInMBB(const MachineFunction &MF, const VarLocInMBB &V, |
674 | const VarLocMap &VarLocIDs, const char *msg, |
675 | raw_ostream &Out) const; |
676 | |
677 | /// Calculate the liveness information for the given machine function. |
678 | bool runOnMachineFunction(MachineFunction &MF) override; |
679 | }; |
680 | |
681 | } // end anonymous namespace |
682 | |
683 | //===----------------------------------------------------------------------===// |
684 | // Implementation |
685 | //===----------------------------------------------------------------------===// |
686 | |
687 | char LiveDebugValues::ID = 0; |
688 | |
689 | char &llvm::LiveDebugValuesID = LiveDebugValues::ID; |
690 | |
691 | INITIALIZE_PASS(LiveDebugValues, DEBUG_TYPE, "Live DEBUG_VALUE analysis",static void *initializeLiveDebugValuesPassOnce(PassRegistry & Registry) { PassInfo *PI = new PassInfo( "Live DEBUG_VALUE analysis" , "livedebugvalues", &LiveDebugValues::ID, PassInfo::NormalCtor_t (callDefaultCtor<LiveDebugValues>), false, false); Registry .registerPass(*PI, true); return PI; } static llvm::once_flag InitializeLiveDebugValuesPassFlag; void llvm::initializeLiveDebugValuesPass (PassRegistry &Registry) { llvm::call_once(InitializeLiveDebugValuesPassFlag , initializeLiveDebugValuesPassOnce, std::ref(Registry)); } |
692 | false, false)static void *initializeLiveDebugValuesPassOnce(PassRegistry & Registry) { PassInfo *PI = new PassInfo( "Live DEBUG_VALUE analysis" , "livedebugvalues", &LiveDebugValues::ID, PassInfo::NormalCtor_t (callDefaultCtor<LiveDebugValues>), false, false); Registry .registerPass(*PI, true); return PI; } static llvm::once_flag InitializeLiveDebugValuesPassFlag; void llvm::initializeLiveDebugValuesPass (PassRegistry &Registry) { llvm::call_once(InitializeLiveDebugValuesPassFlag , initializeLiveDebugValuesPassOnce, std::ref(Registry)); } |
693 | |
694 | /// Default construct and initialize the pass. |
695 | LiveDebugValues::LiveDebugValues() : MachineFunctionPass(ID) { |
696 | initializeLiveDebugValuesPass(*PassRegistry::getPassRegistry()); |
697 | } |
698 | |
699 | /// Tell the pass manager which passes we depend on and what information we |
700 | /// preserve. |
701 | void LiveDebugValues::getAnalysisUsage(AnalysisUsage &AU) const { |
702 | AU.setPreservesCFG(); |
703 | MachineFunctionPass::getAnalysisUsage(AU); |
704 | } |
705 | |
706 | /// Erase a variable from the set of open ranges, and additionally erase any |
707 | /// fragments that may overlap it. If the VarLoc is a buckup location, erase |
708 | /// the variable from the EntryValuesBackupVars set, indicating we should stop |
709 | /// tracking its backup entry location. Otherwise, if the VarLoc is primary |
710 | /// location, erase the variable from the Vars set. |
711 | void LiveDebugValues::OpenRangesSet::erase(const VarLoc &VL) { |
712 | // Erasure helper. |
713 | auto DoErase = [VL, this](DebugVariable VarToErase) { |
714 | auto *EraseFrom = VL.isEntryBackupLoc() ? &EntryValuesBackupVars : &Vars; |
715 | auto It = EraseFrom->find(VarToErase); |
716 | if (It != EraseFrom->end()) { |
717 | LocIndex ID = It->second; |
718 | VarLocs.reset(ID.getAsRawInteger()); |
719 | EraseFrom->erase(It); |
720 | } |
721 | }; |
722 | |
723 | DebugVariable Var = VL.Var; |
724 | |
725 | // Erase the variable/fragment that ends here. |
726 | DoErase(Var); |
727 | |
728 | // Extract the fragment. Interpret an empty fragment as one that covers all |
729 | // possible bits. |
730 | FragmentInfo ThisFragment = Var.getFragmentOrDefault(); |
731 | |
732 | // There may be fragments that overlap the designated fragment. Look them up |
733 | // in the pre-computed overlap map, and erase them too. |
734 | auto MapIt = OverlappingFragments.find({Var.getVariable(), ThisFragment}); |
735 | if (MapIt != OverlappingFragments.end()) { |
736 | for (auto Fragment : MapIt->second) { |
737 | LiveDebugValues::OptFragmentInfo FragmentHolder; |
738 | if (!DebugVariable::isDefaultFragment(Fragment)) |
739 | FragmentHolder = LiveDebugValues::OptFragmentInfo(Fragment); |
740 | DoErase({Var.getVariable(), FragmentHolder, Var.getInlinedAt()}); |
741 | } |
742 | } |
743 | } |
744 | |
745 | void LiveDebugValues::OpenRangesSet::erase(const VarLocSet &KillSet, |
746 | const VarLocMap &VarLocIDs) { |
747 | VarLocs.intersectWithComplement(KillSet); |
748 | for (uint64_t ID : KillSet) { |
749 | const VarLoc *VL = &VarLocIDs[LocIndex::fromRawInteger(ID)]; |
750 | auto *EraseFrom = VL->isEntryBackupLoc() ? &EntryValuesBackupVars : &Vars; |
751 | EraseFrom->erase(VL->Var); |
752 | } |
753 | } |
754 | |
755 | void LiveDebugValues::OpenRangesSet::insert(LocIndex VarLocID, |
756 | const VarLoc &VL) { |
757 | auto *InsertInto = VL.isEntryBackupLoc() ? &EntryValuesBackupVars : &Vars; |
758 | VarLocs.set(VarLocID.getAsRawInteger()); |
759 | InsertInto->insert({VL.Var, VarLocID}); |
760 | } |
761 | |
762 | /// Return the Loc ID of an entry value backup location, if it exists for the |
763 | /// variable. |
764 | llvm::Optional<LocIndex> |
765 | LiveDebugValues::OpenRangesSet::getEntryValueBackup(DebugVariable Var) { |
766 | auto It = EntryValuesBackupVars.find(Var); |
767 | if (It != EntryValuesBackupVars.end()) |
768 | return It->second; |
769 | |
770 | return llvm::None; |
771 | } |
772 | |
773 | void LiveDebugValues::collectIDsForReg(VarLocSet &Collected, uint32_t Reg, |
774 | const VarLocSet &CollectFrom) const { |
775 | // The half-open interval [FirstIndexForReg, FirstInvalidIndex) contains all |
776 | // possible VarLoc IDs for VarLocs of kind RegisterKind which live in Reg. |
777 | uint64_t FirstIndexForReg = LocIndex::rawIndexForReg(Reg); |
778 | uint64_t FirstInvalidIndex = LocIndex::rawIndexForReg(Reg + 1); |
779 | // Iterate through that half-open interval and collect all the set IDs. |
780 | for (auto It = CollectFrom.find(FirstIndexForReg), End = CollectFrom.end(); |
781 | It != End && *It < FirstInvalidIndex; ++It) |
782 | Collected.set(*It); |
783 | } |
784 | |
785 | void LiveDebugValues::getUsedRegs(const VarLocSet &CollectFrom, |
786 | SmallVectorImpl<uint32_t> &UsedRegs) const { |
787 | // All register-based VarLocs are assigned indices greater than or equal to |
788 | // FirstRegIndex. |
789 | uint64_t FirstRegIndex = LocIndex::rawIndexForReg(1); |
790 | for (auto It = CollectFrom.find(FirstRegIndex), End = CollectFrom.end(); |
791 | It != End;) { |
792 | // We found a VarLoc ID for a VarLoc that lives in a register. Figure out |
793 | // which register and add it to UsedRegs. |
794 | uint32_t FoundReg = LocIndex::fromRawInteger(*It).Location; |
795 | assert((UsedRegs.empty() || FoundReg != UsedRegs.back()) &&(((UsedRegs.empty() || FoundReg != UsedRegs.back()) && "Duplicate used reg") ? static_cast<void> (0) : __assert_fail ("(UsedRegs.empty() || FoundReg != UsedRegs.back()) && \"Duplicate used reg\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 796, __PRETTY_FUNCTION__)) |
796 | "Duplicate used reg")(((UsedRegs.empty() || FoundReg != UsedRegs.back()) && "Duplicate used reg") ? static_cast<void> (0) : __assert_fail ("(UsedRegs.empty() || FoundReg != UsedRegs.back()) && \"Duplicate used reg\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 796, __PRETTY_FUNCTION__)); |
797 | UsedRegs.push_back(FoundReg); |
798 | |
799 | // Skip to the next /set/ register. Note that this finds a lower bound, so |
800 | // even if there aren't any VarLocs living in `FoundReg+1`, we're still |
801 | // guaranteed to move on to the next register (or to end()). |
802 | uint64_t NextRegIndex = LocIndex::rawIndexForReg(FoundReg + 1); |
803 | It = CollectFrom.find(NextRegIndex); |
804 | } |
805 | } |
806 | |
807 | //===----------------------------------------------------------------------===// |
808 | // Debug Range Extension Implementation |
809 | //===----------------------------------------------------------------------===// |
810 | |
811 | #ifndef NDEBUG |
812 | void LiveDebugValues::printVarLocInMBB(const MachineFunction &MF, |
813 | const VarLocInMBB &V, |
814 | const VarLocMap &VarLocIDs, |
815 | const char *msg, |
816 | raw_ostream &Out) const { |
817 | Out << '\n' << msg << '\n'; |
818 | for (const MachineBasicBlock &BB : MF) { |
819 | if (!V.count(&BB)) |
820 | continue; |
821 | const VarLocSet &L = getVarLocsInMBB(&BB, V); |
822 | if (L.empty()) |
823 | continue; |
824 | Out << "MBB: " << BB.getNumber() << ":\n"; |
825 | for (uint64_t VLL : L) { |
826 | const VarLoc &VL = VarLocIDs[LocIndex::fromRawInteger(VLL)]; |
827 | Out << " Var: " << VL.Var.getVariable()->getName(); |
828 | Out << " MI: "; |
829 | VL.dump(TRI, Out); |
830 | } |
831 | } |
832 | Out << "\n"; |
833 | } |
834 | #endif |
835 | |
836 | LiveDebugValues::VarLoc::SpillLoc |
837 | LiveDebugValues::extractSpillBaseRegAndOffset(const MachineInstr &MI) { |
838 | assert(MI.hasOneMemOperand() &&((MI.hasOneMemOperand() && "Spill instruction does not have exactly one memory operand?" ) ? static_cast<void> (0) : __assert_fail ("MI.hasOneMemOperand() && \"Spill instruction does not have exactly one memory operand?\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 839, __PRETTY_FUNCTION__)) |
839 | "Spill instruction does not have exactly one memory operand?")((MI.hasOneMemOperand() && "Spill instruction does not have exactly one memory operand?" ) ? static_cast<void> (0) : __assert_fail ("MI.hasOneMemOperand() && \"Spill instruction does not have exactly one memory operand?\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 839, __PRETTY_FUNCTION__)); |
840 | auto MMOI = MI.memoperands_begin(); |
841 | const PseudoSourceValue *PVal = (*MMOI)->getPseudoValue(); |
842 | assert(PVal->kind() == PseudoSourceValue::FixedStack &&((PVal->kind() == PseudoSourceValue::FixedStack && "Inconsistent memory operand in spill instruction") ? static_cast <void> (0) : __assert_fail ("PVal->kind() == PseudoSourceValue::FixedStack && \"Inconsistent memory operand in spill instruction\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 843, __PRETTY_FUNCTION__)) |
843 | "Inconsistent memory operand in spill instruction")((PVal->kind() == PseudoSourceValue::FixedStack && "Inconsistent memory operand in spill instruction") ? static_cast <void> (0) : __assert_fail ("PVal->kind() == PseudoSourceValue::FixedStack && \"Inconsistent memory operand in spill instruction\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 843, __PRETTY_FUNCTION__)); |
844 | int FI = cast<FixedStackPseudoSourceValue>(PVal)->getFrameIndex(); |
845 | const MachineBasicBlock *MBB = MI.getParent(); |
846 | unsigned Reg; |
847 | int Offset = TFI->getFrameIndexReference(*MBB->getParent(), FI, Reg); |
848 | return {Reg, Offset}; |
849 | } |
850 | |
851 | /// Try to salvage the debug entry value if we encounter a new debug value |
852 | /// describing the same parameter, otherwise stop tracking the value. Return |
853 | /// true if we should stop tracking the entry value, otherwise return false. |
854 | bool LiveDebugValues::removeEntryValue(const MachineInstr &MI, |
855 | OpenRangesSet &OpenRanges, |
856 | VarLocMap &VarLocIDs, |
857 | const VarLoc &EntryVL) { |
858 | // Skip the DBG_VALUE which is the debug entry value itself. |
859 | if (MI.isIdenticalTo(EntryVL.MI)) |
860 | return false; |
861 | |
862 | // If the parameter's location is not register location, we can not track |
863 | // the entry value any more. In addition, if the debug expression from the |
864 | // DBG_VALUE is not empty, we can assume the parameter's value has changed |
865 | // indicating that we should stop tracking its entry value as well. |
866 | if (!MI.getOperand(0).isReg() || |
867 | MI.getDebugExpression()->getNumElements() != 0) |
868 | return true; |
869 | |
870 | // If the DBG_VALUE comes from a copy instruction that copies the entry value, |
871 | // it means the parameter's value has not changed and we should be able to use |
872 | // its entry value. |
873 | bool TrySalvageEntryValue = false; |
874 | Register Reg = MI.getOperand(0).getReg(); |
875 | auto I = std::next(MI.getReverseIterator()); |
876 | const MachineOperand *SrcRegOp, *DestRegOp; |
877 | if (I != MI.getParent()->rend()) { |
878 | // TODO: Try to keep tracking of an entry value if we encounter a propagated |
879 | // DBG_VALUE describing the copy of the entry value. (Propagated entry value |
880 | // does not indicate the parameter modification.) |
881 | auto DestSrc = TII->isCopyInstr(*I); |
882 | if (!DestSrc) |
883 | return true; |
884 | |
885 | SrcRegOp = DestSrc->Source; |
886 | DestRegOp = DestSrc->Destination; |
887 | if (Reg != DestRegOp->getReg()) |
888 | return true; |
889 | TrySalvageEntryValue = true; |
890 | } |
891 | |
892 | if (TrySalvageEntryValue) { |
893 | for (uint64_t ID : OpenRanges.getVarLocs()) { |
894 | const VarLoc &VL = VarLocIDs[LocIndex::fromRawInteger(ID)]; |
895 | if (!VL.isEntryBackupLoc()) |
896 | continue; |
897 | |
898 | if (VL.getEntryValueCopyBackupReg() == Reg && |
899 | VL.MI.getOperand(0).getReg() == SrcRegOp->getReg()) |
900 | return false; |
901 | } |
902 | } |
903 | |
904 | return true; |
905 | } |
906 | |
907 | /// End all previous ranges related to @MI and start a new range from @MI |
908 | /// if it is a DBG_VALUE instr. |
909 | void LiveDebugValues::transferDebugValue(const MachineInstr &MI, |
910 | OpenRangesSet &OpenRanges, |
911 | VarLocMap &VarLocIDs) { |
912 | if (!MI.isDebugValue()) |
913 | return; |
914 | const DILocalVariable *Var = MI.getDebugVariable(); |
915 | const DIExpression *Expr = MI.getDebugExpression(); |
916 | const DILocation *DebugLoc = MI.getDebugLoc(); |
917 | const DILocation *InlinedAt = DebugLoc->getInlinedAt(); |
918 | assert(Var->isValidLocationForIntrinsic(DebugLoc) &&((Var->isValidLocationForIntrinsic(DebugLoc) && "Expected inlined-at fields to agree" ) ? static_cast<void> (0) : __assert_fail ("Var->isValidLocationForIntrinsic(DebugLoc) && \"Expected inlined-at fields to agree\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 919, __PRETTY_FUNCTION__)) |
919 | "Expected inlined-at fields to agree")((Var->isValidLocationForIntrinsic(DebugLoc) && "Expected inlined-at fields to agree" ) ? static_cast<void> (0) : __assert_fail ("Var->isValidLocationForIntrinsic(DebugLoc) && \"Expected inlined-at fields to agree\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 919, __PRETTY_FUNCTION__)); |
920 | |
921 | DebugVariable V(Var, Expr, InlinedAt); |
922 | |
923 | // Check if this DBG_VALUE indicates a parameter's value changing. |
924 | // If that is the case, we should stop tracking its entry value. |
925 | auto EntryValBackupID = OpenRanges.getEntryValueBackup(V); |
926 | if (Var->isParameter() && EntryValBackupID) { |
927 | const VarLoc &EntryVL = VarLocIDs[*EntryValBackupID]; |
928 | if (removeEntryValue(MI, OpenRanges, VarLocIDs, EntryVL)) { |
929 | LLVM_DEBUG(dbgs() << "Deleting a DBG entry value because of: ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Deleting a DBG entry value because of: " ; MI.print(dbgs(), false, false, false, true, TII); } } while (false) |
930 | MI.print(dbgs(), /*IsStandalone*/ false,do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Deleting a DBG entry value because of: " ; MI.print(dbgs(), false, false, false, true, TII); } } while (false) |
931 | /*SkipOpers*/ false, /*SkipDebugLoc*/ false,do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Deleting a DBG entry value because of: " ; MI.print(dbgs(), false, false, false, true, TII); } } while (false) |
932 | /*AddNewLine*/ true, TII))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Deleting a DBG entry value because of: " ; MI.print(dbgs(), false, false, false, true, TII); } } while (false); |
933 | OpenRanges.erase(EntryVL); |
934 | } |
935 | } |
936 | |
937 | if (isDbgValueDescribedByReg(MI) || MI.getOperand(0).isImm() || |
938 | MI.getOperand(0).isFPImm() || MI.getOperand(0).isCImm()) { |
939 | // Use normal VarLoc constructor for registers and immediates. |
940 | VarLoc VL(MI, LS); |
941 | // End all previous ranges of VL.Var. |
942 | OpenRanges.erase(VL); |
943 | |
944 | LocIndex ID = VarLocIDs.insert(VL); |
945 | // Add the VarLoc to OpenRanges from this DBG_VALUE. |
946 | OpenRanges.insert(ID, VL); |
947 | } else if (MI.hasOneMemOperand()) { |
948 | llvm_unreachable("DBG_VALUE with mem operand encountered after regalloc?")::llvm::llvm_unreachable_internal("DBG_VALUE with mem operand encountered after regalloc?" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 948); |
949 | } else { |
950 | // This must be an undefined location. We should leave OpenRanges closed. |
951 | assert(MI.getOperand(0).isReg() && MI.getOperand(0).getReg() == 0 &&((MI.getOperand(0).isReg() && MI.getOperand(0).getReg () == 0 && "Unexpected non-undef DBG_VALUE encountered" ) ? static_cast<void> (0) : __assert_fail ("MI.getOperand(0).isReg() && MI.getOperand(0).getReg() == 0 && \"Unexpected non-undef DBG_VALUE encountered\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 952, __PRETTY_FUNCTION__)) |
952 | "Unexpected non-undef DBG_VALUE encountered")((MI.getOperand(0).isReg() && MI.getOperand(0).getReg () == 0 && "Unexpected non-undef DBG_VALUE encountered" ) ? static_cast<void> (0) : __assert_fail ("MI.getOperand(0).isReg() && MI.getOperand(0).getReg() == 0 && \"Unexpected non-undef DBG_VALUE encountered\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 952, __PRETTY_FUNCTION__)); |
953 | } |
954 | } |
955 | |
956 | /// Turn the entry value backup locations into primary locations. |
957 | void LiveDebugValues::emitEntryValues(MachineInstr &MI, |
958 | OpenRangesSet &OpenRanges, |
959 | VarLocMap &VarLocIDs, |
960 | TransferMap &Transfers, |
961 | VarLocSet &KillSet) { |
962 | // Do not insert entry value locations after a terminator. |
963 | if (MI.isTerminator()) |
964 | return; |
965 | |
966 | for (uint64_t ID : KillSet) { |
967 | LocIndex Idx = LocIndex::fromRawInteger(ID); |
968 | const VarLoc &VL = VarLocIDs[Idx]; |
969 | if (!VL.Var.getVariable()->isParameter()) |
970 | continue; |
971 | |
972 | auto DebugVar = VL.Var; |
973 | Optional<LocIndex> EntryValBackupID = |
974 | OpenRanges.getEntryValueBackup(DebugVar); |
975 | |
976 | // If the parameter has the entry value backup, it means we should |
977 | // be able to use its entry value. |
978 | if (!EntryValBackupID) |
979 | continue; |
980 | |
981 | const VarLoc &EntryVL = VarLocIDs[*EntryValBackupID]; |
982 | VarLoc EntryLoc = |
983 | VarLoc::CreateEntryLoc(EntryVL.MI, LS, EntryVL.Expr, EntryVL.Loc.RegNo); |
984 | LocIndex EntryValueID = VarLocIDs.insert(EntryLoc); |
985 | Transfers.push_back({&MI, EntryValueID}); |
986 | OpenRanges.insert(EntryValueID, EntryLoc); |
987 | } |
988 | } |
989 | |
990 | /// Create new TransferDebugPair and insert it in \p Transfers. The VarLoc |
991 | /// with \p OldVarID should be deleted form \p OpenRanges and replaced with |
992 | /// new VarLoc. If \p NewReg is different than default zero value then the |
993 | /// new location will be register location created by the copy like instruction, |
994 | /// otherwise it is variable's location on the stack. |
995 | void LiveDebugValues::insertTransferDebugPair( |
996 | MachineInstr &MI, OpenRangesSet &OpenRanges, TransferMap &Transfers, |
997 | VarLocMap &VarLocIDs, LocIndex OldVarID, TransferKind Kind, |
998 | unsigned NewReg) { |
999 | const MachineInstr *DebugInstr = &VarLocIDs[OldVarID].MI; |
1000 | |
1001 | auto ProcessVarLoc = [&MI, &OpenRanges, &Transfers, &VarLocIDs](VarLoc &VL) { |
1002 | LocIndex LocId = VarLocIDs.insert(VL); |
1003 | |
1004 | // Close this variable's previous location range. |
1005 | OpenRanges.erase(VL); |
1006 | |
1007 | // Record the new location as an open range, and a postponed transfer |
1008 | // inserting a DBG_VALUE for this location. |
1009 | OpenRanges.insert(LocId, VL); |
1010 | assert(!MI.isTerminator() && "Cannot insert DBG_VALUE after terminator")((!MI.isTerminator() && "Cannot insert DBG_VALUE after terminator" ) ? static_cast<void> (0) : __assert_fail ("!MI.isTerminator() && \"Cannot insert DBG_VALUE after terminator\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1010, __PRETTY_FUNCTION__)); |
1011 | TransferDebugPair MIP = {&MI, LocId}; |
1012 | Transfers.push_back(MIP); |
1013 | }; |
1014 | |
1015 | // End all previous ranges of VL.Var. |
1016 | OpenRanges.erase(VarLocIDs[OldVarID]); |
1017 | switch (Kind) { |
1018 | case TransferKind::TransferCopy: { |
1019 | assert(NewReg &&((NewReg && "No register supplied when handling a copy of a debug value" ) ? static_cast<void> (0) : __assert_fail ("NewReg && \"No register supplied when handling a copy of a debug value\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1020, __PRETTY_FUNCTION__)) |
1020 | "No register supplied when handling a copy of a debug value")((NewReg && "No register supplied when handling a copy of a debug value" ) ? static_cast<void> (0) : __assert_fail ("NewReg && \"No register supplied when handling a copy of a debug value\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1020, __PRETTY_FUNCTION__)); |
1021 | // Create a DBG_VALUE instruction to describe the Var in its new |
1022 | // register location. |
1023 | VarLoc VL = VarLoc::CreateCopyLoc(*DebugInstr, LS, NewReg); |
1024 | ProcessVarLoc(VL); |
1025 | LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for register copy:" ; VL.dump(TRI); }; } } while (false) |
1026 | dbgs() << "Creating VarLoc for register copy:";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for register copy:" ; VL.dump(TRI); }; } } while (false) |
1027 | VL.dump(TRI);do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for register copy:" ; VL.dump(TRI); }; } } while (false) |
1028 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for register copy:" ; VL.dump(TRI); }; } } while (false); |
1029 | return; |
1030 | } |
1031 | case TransferKind::TransferSpill: { |
1032 | // Create a DBG_VALUE instruction to describe the Var in its spilled |
1033 | // location. |
1034 | VarLoc::SpillLoc SpillLocation = extractSpillBaseRegAndOffset(MI); |
1035 | VarLoc VL = VarLoc::CreateSpillLoc(*DebugInstr, SpillLocation.SpillBase, |
1036 | SpillLocation.SpillOffset, LS); |
1037 | ProcessVarLoc(VL); |
1038 | LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for spill:" ; VL.dump(TRI); }; } } while (false) |
1039 | dbgs() << "Creating VarLoc for spill:";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for spill:" ; VL.dump(TRI); }; } } while (false) |
1040 | VL.dump(TRI);do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for spill:" ; VL.dump(TRI); }; } } while (false) |
1041 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for spill:" ; VL.dump(TRI); }; } } while (false); |
1042 | return; |
1043 | } |
1044 | case TransferKind::TransferRestore: { |
1045 | assert(NewReg &&((NewReg && "No register supplied when handling a restore of a debug value" ) ? static_cast<void> (0) : __assert_fail ("NewReg && \"No register supplied when handling a restore of a debug value\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1046, __PRETTY_FUNCTION__)) |
1046 | "No register supplied when handling a restore of a debug value")((NewReg && "No register supplied when handling a restore of a debug value" ) ? static_cast<void> (0) : __assert_fail ("NewReg && \"No register supplied when handling a restore of a debug value\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1046, __PRETTY_FUNCTION__)); |
1047 | // DebugInstr refers to the pre-spill location, therefore we can reuse |
1048 | // its expression. |
1049 | VarLoc VL = VarLoc::CreateCopyLoc(*DebugInstr, LS, NewReg); |
1050 | ProcessVarLoc(VL); |
1051 | LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for restore:" ; VL.dump(TRI); }; } } while (false) |
1052 | dbgs() << "Creating VarLoc for restore:";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for restore:" ; VL.dump(TRI); }; } } while (false) |
1053 | VL.dump(TRI);do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for restore:" ; VL.dump(TRI); }; } } while (false) |
1054 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { dbgs() << "Creating VarLoc for restore:" ; VL.dump(TRI); }; } } while (false); |
1055 | return; |
1056 | } |
1057 | } |
1058 | llvm_unreachable("Invalid transfer kind")::llvm::llvm_unreachable_internal("Invalid transfer kind", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1058); |
1059 | } |
1060 | |
1061 | /// A definition of a register may mark the end of a range. |
1062 | void LiveDebugValues::transferRegisterDef( |
1063 | MachineInstr &MI, OpenRangesSet &OpenRanges, VarLocMap &VarLocIDs, |
1064 | TransferMap &Transfers) { |
1065 | |
1066 | // Meta Instructions do not affect the debug liveness of any register they |
1067 | // define. |
1068 | if (MI.isMetaInstruction()) |
1069 | return; |
1070 | |
1071 | MachineFunction *MF = MI.getMF(); |
1072 | const TargetLowering *TLI = MF->getSubtarget().getTargetLowering(); |
1073 | unsigned SP = TLI->getStackPointerRegisterToSaveRestore(); |
1074 | |
1075 | // Find the regs killed by MI, and find regmasks of preserved regs. |
1076 | // Max out the number of statically allocated elements in `DeadRegs`, as this |
1077 | // prevents fallback to std::set::count() operations. |
1078 | SmallSet<uint32_t, 32> DeadRegs; |
1079 | SmallVector<const uint32_t *, 4> RegMasks; |
1080 | for (const MachineOperand &MO : MI.operands()) { |
1081 | // Determine whether the operand is a register def. |
1082 | if (MO.isReg() && MO.isDef() && MO.getReg() && |
1083 | Register::isPhysicalRegister(MO.getReg()) && |
1084 | !(MI.isCall() && MO.getReg() == SP)) { |
1085 | // Remove ranges of all aliased registers. |
1086 | for (MCRegAliasIterator RAI(MO.getReg(), TRI, true); RAI.isValid(); ++RAI) |
1087 | // FIXME: Can we break out of this loop early if no insertion occurs? |
1088 | DeadRegs.insert(*RAI); |
1089 | } else if (MO.isRegMask()) { |
1090 | RegMasks.push_back(MO.getRegMask()); |
1091 | } |
1092 | } |
1093 | |
1094 | // Erase VarLocs which reside in one of the dead registers. For performance |
1095 | // reasons, it's critical to not iterate over the full set of open VarLocs. |
1096 | // Iterate over the set of dying/used regs instead. |
1097 | VarLocSet KillSet(Alloc); |
1098 | for (uint32_t DeadReg : DeadRegs) |
1099 | collectIDsForReg(KillSet, DeadReg, OpenRanges.getVarLocs()); |
1100 | if (!RegMasks.empty()) { |
1101 | SmallVector<uint32_t, 32> UsedRegs; |
1102 | getUsedRegs(OpenRanges.getVarLocs(), UsedRegs); |
1103 | for (uint32_t Reg : UsedRegs) { |
1104 | // The VarLocs residing in this register are already in the kill set. |
1105 | if (DeadRegs.count(Reg)) |
1106 | continue; |
1107 | |
1108 | // Remove ranges of all clobbered registers. Register masks don't usually |
1109 | // list SP as preserved. Assume that call instructions never clobber SP, |
1110 | // because some backends (e.g., AArch64) never list SP in the regmask. |
1111 | // While the debug info may be off for an instruction or two around |
1112 | // callee-cleanup calls, transferring the DEBUG_VALUE across the call is |
1113 | // still a better user experience. |
1114 | if (Reg == SP) |
1115 | continue; |
1116 | bool AnyRegMaskKillsReg = |
1117 | any_of(RegMasks, [Reg](const uint32_t *RegMask) { |
1118 | return MachineOperand::clobbersPhysReg(RegMask, Reg); |
1119 | }); |
1120 | if (AnyRegMaskKillsReg) |
1121 | collectIDsForReg(KillSet, Reg, OpenRanges.getVarLocs()); |
1122 | } |
1123 | } |
1124 | OpenRanges.erase(KillSet, VarLocIDs); |
1125 | |
1126 | if (auto *TPC = getAnalysisIfAvailable<TargetPassConfig>()) { |
1127 | auto &TM = TPC->getTM<TargetMachine>(); |
1128 | if (TM.Options.EnableDebugEntryValues) |
1129 | emitEntryValues(MI, OpenRanges, VarLocIDs, Transfers, KillSet); |
1130 | } |
1131 | } |
1132 | |
1133 | bool LiveDebugValues::isSpillInstruction(const MachineInstr &MI, |
1134 | MachineFunction *MF) { |
1135 | // TODO: Handle multiple stores folded into one. |
1136 | if (!MI.hasOneMemOperand()) |
1137 | return false; |
1138 | |
1139 | if (!MI.getSpillSize(TII) && !MI.getFoldedSpillSize(TII)) |
1140 | return false; // This is not a spill instruction, since no valid size was |
1141 | // returned from either function. |
1142 | |
1143 | return true; |
1144 | } |
1145 | |
1146 | bool LiveDebugValues::isLocationSpill(const MachineInstr &MI, |
1147 | MachineFunction *MF, unsigned &Reg) { |
1148 | if (!isSpillInstruction(MI, MF)) |
1149 | return false; |
1150 | |
1151 | auto isKilledReg = [&](const MachineOperand MO, unsigned &Reg) { |
1152 | if (!MO.isReg() || !MO.isUse()) { |
1153 | Reg = 0; |
1154 | return false; |
1155 | } |
1156 | Reg = MO.getReg(); |
1157 | return MO.isKill(); |
1158 | }; |
1159 | |
1160 | for (const MachineOperand &MO : MI.operands()) { |
1161 | // In a spill instruction generated by the InlineSpiller the spilled |
1162 | // register has its kill flag set. |
1163 | if (isKilledReg(MO, Reg)) |
1164 | return true; |
1165 | if (Reg != 0) { |
1166 | // Check whether next instruction kills the spilled register. |
1167 | // FIXME: Current solution does not cover search for killed register in |
1168 | // bundles and instructions further down the chain. |
1169 | auto NextI = std::next(MI.getIterator()); |
1170 | // Skip next instruction that points to basic block end iterator. |
1171 | if (MI.getParent()->end() == NextI) |
1172 | continue; |
1173 | unsigned RegNext; |
1174 | for (const MachineOperand &MONext : NextI->operands()) { |
1175 | // Return true if we came across the register from the |
1176 | // previous spill instruction that is killed in NextI. |
1177 | if (isKilledReg(MONext, RegNext) && RegNext == Reg) |
1178 | return true; |
1179 | } |
1180 | } |
1181 | } |
1182 | // Return false if we didn't find spilled register. |
1183 | return false; |
1184 | } |
1185 | |
1186 | Optional<LiveDebugValues::VarLoc::SpillLoc> |
1187 | LiveDebugValues::isRestoreInstruction(const MachineInstr &MI, |
1188 | MachineFunction *MF, unsigned &Reg) { |
1189 | if (!MI.hasOneMemOperand()) |
1190 | return None; |
1191 | |
1192 | // FIXME: Handle folded restore instructions with more than one memory |
1193 | // operand. |
1194 | if (MI.getRestoreSize(TII)) { |
1195 | Reg = MI.getOperand(0).getReg(); |
1196 | return extractSpillBaseRegAndOffset(MI); |
1197 | } |
1198 | return None; |
1199 | } |
1200 | |
1201 | /// A spilled register may indicate that we have to end the current range of |
1202 | /// a variable and create a new one for the spill location. |
1203 | /// A restored register may indicate the reverse situation. |
1204 | /// We don't want to insert any instructions in process(), so we just create |
1205 | /// the DBG_VALUE without inserting it and keep track of it in \p Transfers. |
1206 | /// It will be inserted into the BB when we're done iterating over the |
1207 | /// instructions. |
1208 | void LiveDebugValues::transferSpillOrRestoreInst(MachineInstr &MI, |
1209 | OpenRangesSet &OpenRanges, |
1210 | VarLocMap &VarLocIDs, |
1211 | TransferMap &Transfers) { |
1212 | MachineFunction *MF = MI.getMF(); |
1213 | TransferKind TKind; |
1214 | unsigned Reg; |
1215 | Optional<VarLoc::SpillLoc> Loc; |
1216 | |
1217 | LLVM_DEBUG(dbgs() << "Examining instruction: "; MI.dump();)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Examining instruction: " ; MI.dump();; } } while (false); |
1218 | |
1219 | // First, if there are any DBG_VALUEs pointing at a spill slot that is |
1220 | // written to, then close the variable location. The value in memory |
1221 | // will have changed. |
1222 | VarLocSet KillSet(Alloc); |
1223 | if (isSpillInstruction(MI, MF)) { |
1224 | Loc = extractSpillBaseRegAndOffset(MI); |
1225 | for (uint64_t ID : OpenRanges.getVarLocs()) { |
1226 | LocIndex Idx = LocIndex::fromRawInteger(ID); |
1227 | const VarLoc &VL = VarLocIDs[Idx]; |
1228 | if (VL.Kind == VarLoc::SpillLocKind && VL.Loc.SpillLocation == *Loc) { |
1229 | // This location is overwritten by the current instruction -- terminate |
1230 | // the open range, and insert an explicit DBG_VALUE $noreg. |
1231 | // |
1232 | // Doing this at a later stage would require re-interpreting all |
1233 | // DBG_VALUes and DIExpressions to identify whether they point at |
1234 | // memory, and then analysing all memory writes to see if they |
1235 | // overwrite that memory, which is expensive. |
1236 | // |
1237 | // At this stage, we already know which DBG_VALUEs are for spills and |
1238 | // where they are located; it's best to fix handle overwrites now. |
1239 | KillSet.set(ID); |
1240 | VarLoc UndefVL = VarLoc::CreateCopyLoc(VL.MI, LS, 0); |
1241 | LocIndex UndefLocID = VarLocIDs.insert(UndefVL); |
1242 | Transfers.push_back({&MI, UndefLocID}); |
1243 | } |
1244 | } |
1245 | OpenRanges.erase(KillSet, VarLocIDs); |
1246 | } |
1247 | |
1248 | // Try to recognise spill and restore instructions that may create a new |
1249 | // variable location. |
1250 | if (isLocationSpill(MI, MF, Reg)) { |
1251 | TKind = TransferKind::TransferSpill; |
1252 | LLVM_DEBUG(dbgs() << "Recognized as spill: "; MI.dump();)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Recognized as spill: " ; MI.dump();; } } while (false); |
1253 | LLVM_DEBUG(dbgs() << "Register: " << Reg << " " << printReg(Reg, TRI)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Register: " << Reg << " " << printReg(Reg, TRI) << "\n"; } } while (false) |
1254 | << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Register: " << Reg << " " << printReg(Reg, TRI) << "\n"; } } while (false); |
1255 | } else { |
1256 | if (!(Loc = isRestoreInstruction(MI, MF, Reg))) |
1257 | return; |
1258 | TKind = TransferKind::TransferRestore; |
1259 | LLVM_DEBUG(dbgs() << "Recognized as restore: "; MI.dump();)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Recognized as restore: " ; MI.dump();; } } while (false); |
1260 | LLVM_DEBUG(dbgs() << "Register: " << Reg << " " << printReg(Reg, TRI)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Register: " << Reg << " " << printReg(Reg, TRI) << "\n"; } } while (false) |
1261 | << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Register: " << Reg << " " << printReg(Reg, TRI) << "\n"; } } while (false); |
1262 | } |
1263 | // Check if the register or spill location is the location of a debug value. |
1264 | for (uint64_t ID : OpenRanges.getVarLocs()) { |
1265 | LocIndex Idx = LocIndex::fromRawInteger(ID); |
1266 | const VarLoc &VL = VarLocIDs[Idx]; |
1267 | if (TKind == TransferKind::TransferSpill && VL.isDescribedByReg() == Reg) { |
1268 | LLVM_DEBUG(dbgs() << "Spilling Register " << printReg(Reg, TRI) << '('do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Spilling Register " << printReg(Reg, TRI) << '(' << VL.Var.getVariable( )->getName() << ")\n"; } } while (false) |
1269 | << VL.Var.getVariable()->getName() << ")\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Spilling Register " << printReg(Reg, TRI) << '(' << VL.Var.getVariable( )->getName() << ")\n"; } } while (false); |
1270 | } else if (TKind == TransferKind::TransferRestore && |
1271 | VL.Kind == VarLoc::SpillLocKind && |
1272 | VL.Loc.SpillLocation == *Loc) { |
1273 | LLVM_DEBUG(dbgs() << "Restoring Register " << printReg(Reg, TRI) << '('do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Restoring Register " << printReg(Reg, TRI) << '(' << VL.Var.getVariable( )->getName() << ")\n"; } } while (false) |
1274 | << VL.Var.getVariable()->getName() << ")\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Restoring Register " << printReg(Reg, TRI) << '(' << VL.Var.getVariable( )->getName() << ")\n"; } } while (false); |
1275 | } else |
1276 | continue; |
1277 | insertTransferDebugPair(MI, OpenRanges, Transfers, VarLocIDs, Idx, TKind, |
1278 | Reg); |
1279 | return; |
1280 | } |
1281 | } |
1282 | |
1283 | /// If \p MI is a register copy instruction, that copies a previously tracked |
1284 | /// value from one register to another register that is callee saved, we |
1285 | /// create new DBG_VALUE instruction described with copy destination register. |
1286 | void LiveDebugValues::transferRegisterCopy(MachineInstr &MI, |
1287 | OpenRangesSet &OpenRanges, |
1288 | VarLocMap &VarLocIDs, |
1289 | TransferMap &Transfers) { |
1290 | auto DestSrc = TII->isCopyInstr(MI); |
1291 | if (!DestSrc) |
1292 | return; |
1293 | |
1294 | const MachineOperand *DestRegOp = DestSrc->Destination; |
1295 | const MachineOperand *SrcRegOp = DestSrc->Source; |
1296 | |
1297 | if (!DestRegOp->isDef()) |
1298 | return; |
1299 | |
1300 | auto isCalleeSavedReg = [&](unsigned Reg) { |
1301 | for (MCRegAliasIterator RAI(Reg, TRI, true); RAI.isValid(); ++RAI) |
1302 | if (CalleeSavedRegs.test(*RAI)) |
1303 | return true; |
1304 | return false; |
1305 | }; |
1306 | |
1307 | Register SrcReg = SrcRegOp->getReg(); |
1308 | Register DestReg = DestRegOp->getReg(); |
1309 | |
1310 | // We want to recognize instructions where destination register is callee |
1311 | // saved register. If register that could be clobbered by the call is |
1312 | // included, there would be a great chance that it is going to be clobbered |
1313 | // soon. It is more likely that previous register location, which is callee |
1314 | // saved, is going to stay unclobbered longer, even if it is killed. |
1315 | if (!isCalleeSavedReg(DestReg)) |
1316 | return; |
1317 | |
1318 | // Remember an entry value movement. If we encounter a new debug value of |
1319 | // a parameter describing only a moving of the value around, rather then |
1320 | // modifying it, we are still able to use the entry value if needed. |
1321 | if (isRegOtherThanSPAndFP(*DestRegOp, MI, TRI)) { |
1322 | for (uint64_t ID : OpenRanges.getVarLocs()) { |
1323 | LocIndex Idx = LocIndex::fromRawInteger(ID); |
1324 | const VarLoc &VL = VarLocIDs[Idx]; |
1325 | if (VL.getEntryValueBackupReg() == SrcReg) { |
1326 | LLVM_DEBUG(dbgs() << "Copy of the entry value: "; MI.dump();)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Copy of the entry value: " ; MI.dump();; } } while (false); |
1327 | VarLoc EntryValLocCopyBackup = |
1328 | VarLoc::CreateEntryCopyBackupLoc(VL.MI, LS, VL.Expr, DestReg); |
1329 | |
1330 | // Stop tracking the original entry value. |
1331 | OpenRanges.erase(VL); |
1332 | |
1333 | // Start tracking the entry value copy. |
1334 | LocIndex EntryValCopyLocID = VarLocIDs.insert(EntryValLocCopyBackup); |
1335 | OpenRanges.insert(EntryValCopyLocID, EntryValLocCopyBackup); |
1336 | break; |
1337 | } |
1338 | } |
1339 | } |
1340 | |
1341 | if (!SrcRegOp->isKill()) |
1342 | return; |
1343 | |
1344 | for (uint64_t ID : OpenRanges.getVarLocs()) { |
1345 | LocIndex Idx = LocIndex::fromRawInteger(ID); |
1346 | if (VarLocIDs[Idx].isDescribedByReg() == SrcReg) { |
1347 | insertTransferDebugPair(MI, OpenRanges, Transfers, VarLocIDs, Idx, |
1348 | TransferKind::TransferCopy, DestReg); |
1349 | return; |
1350 | } |
1351 | } |
1352 | } |
1353 | |
1354 | /// Terminate all open ranges at the end of the current basic block. |
1355 | bool LiveDebugValues::transferTerminator(MachineBasicBlock *CurMBB, |
1356 | OpenRangesSet &OpenRanges, |
1357 | VarLocInMBB &OutLocs, |
1358 | const VarLocMap &VarLocIDs) { |
1359 | bool Changed = false; |
1360 | |
1361 | LLVM_DEBUG(for (uint64_t IDdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (uint64_t ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs in MBB #" << CurMBB ->getNumber() << ": "; VarLocIDs[LocIndex::fromRawInteger (ID)].dump(TRI); }; } } while (false) |
1362 | : OpenRanges.getVarLocs()) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (uint64_t ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs in MBB #" << CurMBB ->getNumber() << ": "; VarLocIDs[LocIndex::fromRawInteger (ID)].dump(TRI); }; } } while (false) |
1363 | // Copy OpenRanges to OutLocs, if not already present.do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (uint64_t ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs in MBB #" << CurMBB ->getNumber() << ": "; VarLocIDs[LocIndex::fromRawInteger (ID)].dump(TRI); }; } } while (false) |
1364 | dbgs() << "Add to OutLocs in MBB #" << CurMBB->getNumber() << ": ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (uint64_t ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs in MBB #" << CurMBB ->getNumber() << ": "; VarLocIDs[LocIndex::fromRawInteger (ID)].dump(TRI); }; } } while (false) |
1365 | VarLocIDs[LocIndex::fromRawInteger(ID)].dump(TRI);do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (uint64_t ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs in MBB #" << CurMBB ->getNumber() << ": "; VarLocIDs[LocIndex::fromRawInteger (ID)].dump(TRI); }; } } while (false) |
1366 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (uint64_t ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs in MBB #" << CurMBB ->getNumber() << ": "; VarLocIDs[LocIndex::fromRawInteger (ID)].dump(TRI); }; } } while (false); |
1367 | VarLocSet &VLS = getVarLocsInMBB(CurMBB, OutLocs); |
1368 | Changed = VLS != OpenRanges.getVarLocs(); |
1369 | // New OutLocs set may be different due to spill, restore or register |
1370 | // copy instruction processing. |
1371 | if (Changed) |
1372 | VLS = OpenRanges.getVarLocs(); |
1373 | OpenRanges.clear(); |
1374 | return Changed; |
1375 | } |
1376 | |
1377 | /// Accumulate a mapping between each DILocalVariable fragment and other |
1378 | /// fragments of that DILocalVariable which overlap. This reduces work during |
1379 | /// the data-flow stage from "Find any overlapping fragments" to "Check if the |
1380 | /// known-to-overlap fragments are present". |
1381 | /// \param MI A previously unprocessed DEBUG_VALUE instruction to analyze for |
1382 | /// fragment usage. |
1383 | /// \param SeenFragments Map from DILocalVariable to all fragments of that |
1384 | /// Variable which are known to exist. |
1385 | /// \param OverlappingFragments The overlap map being constructed, from one |
1386 | /// Var/Fragment pair to a vector of fragments known to overlap. |
1387 | void LiveDebugValues::accumulateFragmentMap(MachineInstr &MI, |
1388 | VarToFragments &SeenFragments, |
1389 | OverlapMap &OverlappingFragments) { |
1390 | DebugVariable MIVar(MI.getDebugVariable(), MI.getDebugExpression(), |
1391 | MI.getDebugLoc()->getInlinedAt()); |
1392 | FragmentInfo ThisFragment = MIVar.getFragmentOrDefault(); |
1393 | |
1394 | // If this is the first sighting of this variable, then we are guaranteed |
1395 | // there are currently no overlapping fragments either. Initialize the set |
1396 | // of seen fragments, record no overlaps for the current one, and return. |
1397 | auto SeenIt = SeenFragments.find(MIVar.getVariable()); |
1398 | if (SeenIt == SeenFragments.end()) { |
1399 | SmallSet<FragmentInfo, 4> OneFragment; |
1400 | OneFragment.insert(ThisFragment); |
1401 | SeenFragments.insert({MIVar.getVariable(), OneFragment}); |
1402 | |
1403 | OverlappingFragments.insert({{MIVar.getVariable(), ThisFragment}, {}}); |
1404 | return; |
1405 | } |
1406 | |
1407 | // If this particular Variable/Fragment pair already exists in the overlap |
1408 | // map, it has already been accounted for. |
1409 | auto IsInOLapMap = |
1410 | OverlappingFragments.insert({{MIVar.getVariable(), ThisFragment}, {}}); |
1411 | if (!IsInOLapMap.second) |
1412 | return; |
1413 | |
1414 | auto &ThisFragmentsOverlaps = IsInOLapMap.first->second; |
1415 | auto &AllSeenFragments = SeenIt->second; |
1416 | |
1417 | // Otherwise, examine all other seen fragments for this variable, with "this" |
1418 | // fragment being a previously unseen fragment. Record any pair of |
1419 | // overlapping fragments. |
1420 | for (auto &ASeenFragment : AllSeenFragments) { |
1421 | // Does this previously seen fragment overlap? |
1422 | if (DIExpression::fragmentsOverlap(ThisFragment, ASeenFragment)) { |
1423 | // Yes: Mark the current fragment as being overlapped. |
1424 | ThisFragmentsOverlaps.push_back(ASeenFragment); |
1425 | // Mark the previously seen fragment as being overlapped by the current |
1426 | // one. |
1427 | auto ASeenFragmentsOverlaps = |
1428 | OverlappingFragments.find({MIVar.getVariable(), ASeenFragment}); |
1429 | assert(ASeenFragmentsOverlaps != OverlappingFragments.end() &&((ASeenFragmentsOverlaps != OverlappingFragments.end() && "Previously seen var fragment has no vector of overlaps") ? static_cast <void> (0) : __assert_fail ("ASeenFragmentsOverlaps != OverlappingFragments.end() && \"Previously seen var fragment has no vector of overlaps\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1430, __PRETTY_FUNCTION__)) |
1430 | "Previously seen var fragment has no vector of overlaps")((ASeenFragmentsOverlaps != OverlappingFragments.end() && "Previously seen var fragment has no vector of overlaps") ? static_cast <void> (0) : __assert_fail ("ASeenFragmentsOverlaps != OverlappingFragments.end() && \"Previously seen var fragment has no vector of overlaps\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1430, __PRETTY_FUNCTION__)); |
1431 | ASeenFragmentsOverlaps->second.push_back(ThisFragment); |
1432 | } |
1433 | } |
1434 | |
1435 | AllSeenFragments.insert(ThisFragment); |
1436 | } |
1437 | |
1438 | /// This routine creates OpenRanges. |
1439 | void LiveDebugValues::process(MachineInstr &MI, OpenRangesSet &OpenRanges, |
1440 | VarLocMap &VarLocIDs, TransferMap &Transfers) { |
1441 | transferDebugValue(MI, OpenRanges, VarLocIDs); |
1442 | transferRegisterDef(MI, OpenRanges, VarLocIDs, Transfers); |
1443 | transferRegisterCopy(MI, OpenRanges, VarLocIDs, Transfers); |
1444 | transferSpillOrRestoreInst(MI, OpenRanges, VarLocIDs, Transfers); |
1445 | } |
1446 | |
1447 | /// This routine joins the analysis results of all incoming edges in @MBB by |
1448 | /// inserting a new DBG_VALUE instruction at the start of the @MBB - if the same |
1449 | /// source variable in all the predecessors of @MBB reside in the same location. |
1450 | bool LiveDebugValues::join( |
1451 | MachineBasicBlock &MBB, VarLocInMBB &OutLocs, VarLocInMBB &InLocs, |
1452 | const VarLocMap &VarLocIDs, |
1453 | SmallPtrSet<const MachineBasicBlock *, 16> &Visited, |
1454 | SmallPtrSetImpl<const MachineBasicBlock *> &ArtificialBlocks, |
1455 | VarLocInMBB &PendingInLocs) { |
1456 | LLVM_DEBUG(dbgs() << "join MBB: " << MBB.getNumber() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "join MBB: " << MBB .getNumber() << "\n"; } } while (false); |
1457 | bool Changed = false; |
1458 | |
1459 | VarLocSet InLocsT(Alloc); // Temporary incoming locations. |
1460 | |
1461 | // For all predecessors of this MBB, find the set of VarLocs that |
1462 | // can be joined. |
1463 | int NumVisited = 0; |
1464 | for (auto p : MBB.predecessors()) { |
1465 | // Ignore backedges if we have not visited the predecessor yet. As the |
1466 | // predecessor hasn't yet had locations propagated into it, most locations |
1467 | // will not yet be valid, so treat them as all being uninitialized and |
1468 | // potentially valid. If a location guessed to be correct here is |
1469 | // invalidated later, we will remove it when we revisit this block. |
1470 | if (!Visited.count(p)) { |
1471 | LLVM_DEBUG(dbgs() << " ignoring unvisited pred MBB: " << p->getNumber()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << " ignoring unvisited pred MBB: " << p->getNumber() << "\n"; } } while (false) |
1472 | << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << " ignoring unvisited pred MBB: " << p->getNumber() << "\n"; } } while (false); |
1473 | continue; |
1474 | } |
1475 | auto OL = OutLocs.find(p); |
1476 | // Join is null in case of empty OutLocs from any of the pred. |
1477 | if (OL == OutLocs.end()) |
1478 | return false; |
1479 | |
1480 | // Just copy over the Out locs to incoming locs for the first visited |
1481 | // predecessor, and for all other predecessors join the Out locs. |
1482 | if (!NumVisited) |
1483 | InLocsT = OL->second; |
1484 | else |
1485 | InLocsT &= OL->second; |
1486 | |
1487 | LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { if (!InLocsT.empty()) { for (uint64_t ID : InLocsT) dbgs() << " gathered candidate incoming var: " << VarLocIDs[LocIndex::fromRawInteger(ID)] .Var.getVariable () ->getName() << "\n"; } }; } } while (false) |
1488 | if (!InLocsT.empty()) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { if (!InLocsT.empty()) { for (uint64_t ID : InLocsT) dbgs() << " gathered candidate incoming var: " << VarLocIDs[LocIndex::fromRawInteger(ID)] .Var.getVariable () ->getName() << "\n"; } }; } } while (false) |
1489 | for (uint64_t ID : InLocsT)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { if (!InLocsT.empty()) { for (uint64_t ID : InLocsT) dbgs() << " gathered candidate incoming var: " << VarLocIDs[LocIndex::fromRawInteger(ID)] .Var.getVariable () ->getName() << "\n"; } }; } } while (false) |
1490 | dbgs() << " gathered candidate incoming var: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { if (!InLocsT.empty()) { for (uint64_t ID : InLocsT) dbgs() << " gathered candidate incoming var: " << VarLocIDs[LocIndex::fromRawInteger(ID)] .Var.getVariable () ->getName() << "\n"; } }; } } while (false) |
1491 | << VarLocIDs[LocIndex::fromRawInteger(ID)]do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { if (!InLocsT.empty()) { for (uint64_t ID : InLocsT) dbgs() << " gathered candidate incoming var: " << VarLocIDs[LocIndex::fromRawInteger(ID)] .Var.getVariable () ->getName() << "\n"; } }; } } while (false) |
1492 | .Var.getVariable()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { if (!InLocsT.empty()) { for (uint64_t ID : InLocsT) dbgs() << " gathered candidate incoming var: " << VarLocIDs[LocIndex::fromRawInteger(ID)] .Var.getVariable () ->getName() << "\n"; } }; } } while (false) |
1493 | ->getName()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { if (!InLocsT.empty()) { for (uint64_t ID : InLocsT) dbgs() << " gathered candidate incoming var: " << VarLocIDs[LocIndex::fromRawInteger(ID)] .Var.getVariable () ->getName() << "\n"; } }; } } while (false) |
1494 | << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { if (!InLocsT.empty()) { for (uint64_t ID : InLocsT) dbgs() << " gathered candidate incoming var: " << VarLocIDs[LocIndex::fromRawInteger(ID)] .Var.getVariable () ->getName() << "\n"; } }; } } while (false) |
1495 | }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { if (!InLocsT.empty()) { for (uint64_t ID : InLocsT) dbgs() << " gathered candidate incoming var: " << VarLocIDs[LocIndex::fromRawInteger(ID)] .Var.getVariable () ->getName() << "\n"; } }; } } while (false) |
1496 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { if (!InLocsT.empty()) { for (uint64_t ID : InLocsT) dbgs() << " gathered candidate incoming var: " << VarLocIDs[LocIndex::fromRawInteger(ID)] .Var.getVariable () ->getName() << "\n"; } }; } } while (false); |
1497 | |
1498 | NumVisited++; |
1499 | } |
1500 | |
1501 | // Filter out DBG_VALUES that are out of scope. |
1502 | VarLocSet KillSet(Alloc); |
1503 | bool IsArtificial = ArtificialBlocks.count(&MBB); |
1504 | if (!IsArtificial) { |
1505 | for (uint64_t ID : InLocsT) { |
1506 | LocIndex Idx = LocIndex::fromRawInteger(ID); |
1507 | if (!VarLocIDs[Idx].dominates(MBB)) { |
1508 | KillSet.set(ID); |
1509 | LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { auto Name = VarLocIDs[Idx].Var.getVariable ()->getName(); dbgs() << " killing " << Name << ", it doesn't dominate MBB\n"; }; } } while (false) |
1510 | auto Name = VarLocIDs[Idx].Var.getVariable()->getName();do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { auto Name = VarLocIDs[Idx].Var.getVariable ()->getName(); dbgs() << " killing " << Name << ", it doesn't dominate MBB\n"; }; } } while (false) |
1511 | dbgs() << " killing " << Name << ", it doesn't dominate MBB\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { auto Name = VarLocIDs[Idx].Var.getVariable ()->getName(); dbgs() << " killing " << Name << ", it doesn't dominate MBB\n"; }; } } while (false) |
1512 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { { auto Name = VarLocIDs[Idx].Var.getVariable ()->getName(); dbgs() << " killing " << Name << ", it doesn't dominate MBB\n"; }; } } while (false); |
1513 | } |
1514 | } |
1515 | } |
1516 | InLocsT.intersectWithComplement(KillSet); |
1517 | |
1518 | // As we are processing blocks in reverse post-order we |
1519 | // should have processed at least one predecessor, unless it |
1520 | // is the entry block which has no predecessor. |
1521 | assert((NumVisited || MBB.pred_empty()) &&(((NumVisited || MBB.pred_empty()) && "Should have processed at least one predecessor" ) ? static_cast<void> (0) : __assert_fail ("(NumVisited || MBB.pred_empty()) && \"Should have processed at least one predecessor\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1522, __PRETTY_FUNCTION__)) |
1522 | "Should have processed at least one predecessor")(((NumVisited || MBB.pred_empty()) && "Should have processed at least one predecessor" ) ? static_cast<void> (0) : __assert_fail ("(NumVisited || MBB.pred_empty()) && \"Should have processed at least one predecessor\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1522, __PRETTY_FUNCTION__)); |
1523 | |
1524 | VarLocSet &ILS = getVarLocsInMBB(&MBB, InLocs); |
1525 | VarLocSet &Pending = getVarLocsInMBB(&MBB, PendingInLocs); |
1526 | |
1527 | // New locations will have DBG_VALUE insts inserted at the start of the |
1528 | // block, after location propagation has finished. Record the insertions |
1529 | // that we need to perform in the Pending set. |
1530 | VarLocSet Diff = InLocsT; |
1531 | Diff.intersectWithComplement(ILS); |
1532 | Pending.set(Diff); |
1533 | ILS.set(Diff); |
1534 | NumInserted += Diff.count(); |
1535 | Changed |= !Diff.empty(); |
1536 | |
1537 | // We may have lost locations by learning about a predecessor that either |
1538 | // loses or moves a variable. Find any locations in ILS that are not in the |
1539 | // new in-locations, and delete those. |
1540 | VarLocSet Removed = ILS; |
1541 | Removed.intersectWithComplement(InLocsT); |
1542 | Pending.intersectWithComplement(Removed); |
1543 | ILS.intersectWithComplement(Removed); |
1544 | NumRemoved += Removed.count(); |
1545 | Changed |= !Removed.empty(); |
1546 | |
1547 | return Changed; |
1548 | } |
1549 | |
1550 | void LiveDebugValues::flushPendingLocs(VarLocInMBB &PendingInLocs, |
1551 | VarLocMap &VarLocIDs) { |
1552 | // PendingInLocs records all locations propagated into blocks, which have |
1553 | // not had DBG_VALUE insts created. Go through and create those insts now. |
1554 | for (auto &Iter : PendingInLocs) { |
1555 | // Map is keyed on a constant pointer, unwrap it so we can insert insts. |
1556 | auto &MBB = const_cast<MachineBasicBlock &>(*Iter.first); |
1557 | VarLocSet &Pending = Iter.second; |
1558 | |
1559 | for (uint64_t ID : Pending) { |
1560 | // The ID location is live-in to MBB -- work out what kind of machine |
1561 | // location it is and create a DBG_VALUE. |
1562 | const VarLoc &DiffIt = VarLocIDs[LocIndex::fromRawInteger(ID)]; |
1563 | if (DiffIt.isEntryBackupLoc()) |
1564 | continue; |
1565 | MachineInstr *MI = DiffIt.BuildDbgValue(*MBB.getParent()); |
1566 | MBB.insert(MBB.instr_begin(), MI); |
1567 | |
1568 | (void)MI; |
1569 | LLVM_DEBUG(dbgs() << "Inserted: "; MI->dump();)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Inserted: "; MI->dump ();; } } while (false); |
1570 | } |
1571 | } |
1572 | } |
1573 | |
1574 | bool LiveDebugValues::isEntryValueCandidate( |
1575 | const MachineInstr &MI, const DefinedRegsSet &DefinedRegs) const { |
1576 | assert(MI.isDebugValue() && "This must be DBG_VALUE.")((MI.isDebugValue() && "This must be DBG_VALUE.") ? static_cast <void> (0) : __assert_fail ("MI.isDebugValue() && \"This must be DBG_VALUE.\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1576, __PRETTY_FUNCTION__)); |
1577 | |
1578 | // TODO: Add support for local variables that are expressed in terms of |
1579 | // parameters entry values. |
1580 | // TODO: Add support for modified arguments that can be expressed |
1581 | // by using its entry value. |
1582 | auto *DIVar = MI.getDebugVariable(); |
1583 | if (!DIVar->isParameter()) |
1584 | return false; |
1585 | |
1586 | // Do not consider parameters that belong to an inlined function. |
1587 | if (MI.getDebugLoc()->getInlinedAt()) |
1588 | return false; |
1589 | |
1590 | // Do not consider indirect debug values (TODO: explain why). |
1591 | if (MI.isIndirectDebugValue()) |
1592 | return false; |
1593 | |
1594 | // Only consider parameters that are described using registers. Parameters |
1595 | // that are passed on the stack are not yet supported, so ignore debug |
1596 | // values that are described by the frame or stack pointer. |
1597 | if (!isRegOtherThanSPAndFP(MI.getOperand(0), MI, TRI)) |
1598 | return false; |
1599 | |
1600 | // If a parameter's value has been propagated from the caller, then the |
1601 | // parameter's DBG_VALUE may be described using a register defined by some |
1602 | // instruction in the entry block, in which case we shouldn't create an |
1603 | // entry value. |
1604 | if (DefinedRegs.count(MI.getOperand(0).getReg())) |
1605 | return false; |
1606 | |
1607 | // TODO: Add support for parameters that have a pre-existing debug expressions |
1608 | // (e.g. fragments, or indirect parameters using DW_OP_deref). |
1609 | if (MI.getDebugExpression()->getNumElements() > 0) |
1610 | return false; |
1611 | |
1612 | return true; |
1613 | } |
1614 | |
1615 | /// Collect all register defines (including aliases) for the given instruction. |
1616 | static void collectRegDefs(const MachineInstr &MI, DefinedRegsSet &Regs, |
1617 | const TargetRegisterInfo *TRI) { |
1618 | for (const MachineOperand &MO : MI.operands()) |
1619 | if (MO.isReg() && MO.isDef() && MO.getReg()) |
1620 | for (MCRegAliasIterator AI(MO.getReg(), TRI, true); AI.isValid(); ++AI) |
1621 | Regs.insert(*AI); |
1622 | } |
1623 | |
1624 | /// This routine records the entry values of function parameters. The values |
1625 | /// could be used as backup values. If we loose the track of some unmodified |
1626 | /// parameters, the backup values will be used as a primary locations. |
1627 | void LiveDebugValues::recordEntryValue(const MachineInstr &MI, |
1628 | const DefinedRegsSet &DefinedRegs, |
1629 | OpenRangesSet &OpenRanges, |
1630 | VarLocMap &VarLocIDs) { |
1631 | if (auto *TPC = getAnalysisIfAvailable<TargetPassConfig>()) { |
1632 | auto &TM = TPC->getTM<TargetMachine>(); |
1633 | if (!TM.Options.EnableDebugEntryValues) |
1634 | return; |
1635 | } |
1636 | |
1637 | DebugVariable V(MI.getDebugVariable(), MI.getDebugExpression(), |
1638 | MI.getDebugLoc()->getInlinedAt()); |
1639 | |
1640 | if (!isEntryValueCandidate(MI, DefinedRegs) || |
1641 | OpenRanges.getEntryValueBackup(V)) |
1642 | return; |
1643 | |
1644 | LLVM_DEBUG(dbgs() << "Creating the backup entry location: "; MI.dump();)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Creating the backup entry location: " ; MI.dump();; } } while (false); |
1645 | |
1646 | // Create the entry value and use it as a backup location until it is |
1647 | // valid. It is valid until a parameter is not changed. |
1648 | DIExpression *NewExpr = |
1649 | DIExpression::prepend(MI.getDebugExpression(), DIExpression::EntryValue); |
1650 | VarLoc EntryValLocAsBackup = VarLoc::CreateEntryBackupLoc(MI, LS, NewExpr); |
1651 | LocIndex EntryValLocID = VarLocIDs.insert(EntryValLocAsBackup); |
1652 | OpenRanges.insert(EntryValLocID, EntryValLocAsBackup); |
1653 | } |
1654 | |
1655 | /// Calculate the liveness information for the given machine function and |
1656 | /// extend ranges across basic blocks. |
1657 | bool LiveDebugValues::ExtendRanges(MachineFunction &MF) { |
1658 | LLVM_DEBUG(dbgs() << "\nDebug Range Extension\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "\nDebug Range Extension\n" ; } } while (false); |
1659 | |
1660 | bool Changed = false; |
1661 | bool OLChanged = false; |
1662 | bool MBBJoined = false; |
1663 | |
1664 | VarLocMap VarLocIDs; // Map VarLoc<>unique ID for use in bitvectors. |
1665 | OverlapMap OverlapFragments; // Map of overlapping variable fragments. |
1666 | OpenRangesSet OpenRanges(Alloc, OverlapFragments); |
1667 | // Ranges that are open until end of bb. |
1668 | VarLocInMBB OutLocs; // Ranges that exist beyond bb. |
1669 | VarLocInMBB InLocs; // Ranges that are incoming after joining. |
1670 | TransferMap Transfers; // DBG_VALUEs associated with transfers (such as |
1671 | // spills, copies and restores). |
1672 | VarLocInMBB PendingInLocs; // Ranges that are incoming after joining, but |
1673 | // that we have deferred creating DBG_VALUE insts |
1674 | // for immediately. |
1675 | |
1676 | VarToFragments SeenFragments; |
1677 | |
1678 | // Blocks which are artificial, i.e. blocks which exclusively contain |
1679 | // instructions without locations, or with line 0 locations. |
1680 | SmallPtrSet<const MachineBasicBlock *, 16> ArtificialBlocks; |
1681 | |
1682 | DenseMap<unsigned int, MachineBasicBlock *> OrderToBB; |
1683 | DenseMap<MachineBasicBlock *, unsigned int> BBToOrder; |
1684 | std::priority_queue<unsigned int, std::vector<unsigned int>, |
1685 | std::greater<unsigned int>> |
1686 | Worklist; |
1687 | std::priority_queue<unsigned int, std::vector<unsigned int>, |
1688 | std::greater<unsigned int>> |
1689 | Pending; |
1690 | |
1691 | // Set of register defines that are seen when traversing the entry block |
1692 | // looking for debug entry value candidates. |
1693 | DefinedRegsSet DefinedRegs; |
1694 | |
1695 | // Only in the case of entry MBB collect DBG_VALUEs representing |
1696 | // function parameters in order to generate debug entry values for them. |
1697 | MachineBasicBlock &First_MBB = *(MF.begin()); |
1698 | for (auto &MI : First_MBB) { |
1699 | collectRegDefs(MI, DefinedRegs, TRI); |
1700 | if (MI.isDebugValue()) |
1701 | recordEntryValue(MI, DefinedRegs, OpenRanges, VarLocIDs); |
1702 | } |
1703 | |
1704 | // Initialize per-block structures and scan for fragment overlaps. |
1705 | for (auto &MBB : MF) { |
1706 | PendingInLocs.try_emplace(&MBB, Alloc); |
1707 | |
1708 | for (auto &MI : MBB) { |
1709 | if (MI.isDebugValue()) |
1710 | accumulateFragmentMap(MI, SeenFragments, OverlapFragments); |
1711 | } |
1712 | } |
1713 | |
1714 | auto hasNonArtificialLocation = [](const MachineInstr &MI) -> bool { |
1715 | if (const DebugLoc &DL = MI.getDebugLoc()) |
1716 | return DL.getLine() != 0; |
1717 | return false; |
1718 | }; |
1719 | for (auto &MBB : MF) |
1720 | if (none_of(MBB.instrs(), hasNonArtificialLocation)) |
1721 | ArtificialBlocks.insert(&MBB); |
1722 | |
1723 | LLVM_DEBUG(printVarLocInMBB(MF, OutLocs, VarLocIDs,do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, OutLocs, VarLocIDs , "OutLocs after initialization", dbgs()); } } while (false) |
1724 | "OutLocs after initialization", dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, OutLocs, VarLocIDs , "OutLocs after initialization", dbgs()); } } while (false); |
1725 | |
1726 | ReversePostOrderTraversal<MachineFunction *> RPOT(&MF); |
1727 | unsigned int RPONumber = 0; |
1728 | for (auto RI = RPOT.begin(), RE = RPOT.end(); RI != RE; ++RI) { |
1729 | OrderToBB[RPONumber] = *RI; |
1730 | BBToOrder[*RI] = RPONumber; |
1731 | Worklist.push(RPONumber); |
1732 | ++RPONumber; |
1733 | } |
1734 | // This is a standard "union of predecessor outs" dataflow problem. |
1735 | // To solve it, we perform join() and process() using the two worklist method |
1736 | // until the ranges converge. |
1737 | // Ranges have converged when both worklists are empty. |
1738 | SmallPtrSet<const MachineBasicBlock *, 16> Visited; |
1739 | while (!Worklist.empty() || !Pending.empty()) { |
1740 | // We track what is on the pending worklist to avoid inserting the same |
1741 | // thing twice. We could avoid this with a custom priority queue, but this |
1742 | // is probably not worth it. |
1743 | SmallPtrSet<MachineBasicBlock *, 16> OnPending; |
1744 | LLVM_DEBUG(dbgs() << "Processing Worklist\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Processing Worklist\n" ; } } while (false); |
1745 | while (!Worklist.empty()) { |
1746 | MachineBasicBlock *MBB = OrderToBB[Worklist.top()]; |
1747 | Worklist.pop(); |
1748 | MBBJoined = join(*MBB, OutLocs, InLocs, VarLocIDs, Visited, |
1749 | ArtificialBlocks, PendingInLocs); |
1750 | MBBJoined |= Visited.insert(MBB).second; |
1751 | if (MBBJoined) { |
1752 | MBBJoined = false; |
Value stored to 'MBBJoined' is never read | |
1753 | Changed = true; |
1754 | // Now that we have started to extend ranges across BBs we need to |
1755 | // examine spill, copy and restore instructions to see whether they |
1756 | // operate with registers that correspond to user variables. |
1757 | // First load any pending inlocs. |
1758 | OpenRanges.insertFromLocSet(getVarLocsInMBB(MBB, PendingInLocs), |
1759 | VarLocIDs); |
1760 | for (auto &MI : *MBB) |
1761 | process(MI, OpenRanges, VarLocIDs, Transfers); |
1762 | OLChanged |= transferTerminator(MBB, OpenRanges, OutLocs, VarLocIDs); |
1763 | |
1764 | LLVM_DEBUG(printVarLocInMBB(MF, OutLocs, VarLocIDs,do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, OutLocs, VarLocIDs , "OutLocs after propagating", dbgs()); } } while (false) |
1765 | "OutLocs after propagating", dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, OutLocs, VarLocIDs , "OutLocs after propagating", dbgs()); } } while (false); |
1766 | LLVM_DEBUG(printVarLocInMBB(MF, InLocs, VarLocIDs,do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, InLocs, VarLocIDs , "InLocs after propagating", dbgs()); } } while (false) |
1767 | "InLocs after propagating", dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, InLocs, VarLocIDs , "InLocs after propagating", dbgs()); } } while (false); |
1768 | |
1769 | if (OLChanged) { |
1770 | OLChanged = false; |
1771 | for (auto s : MBB->successors()) |
1772 | if (OnPending.insert(s).second) { |
1773 | Pending.push(BBToOrder[s]); |
1774 | } |
1775 | } |
1776 | } |
1777 | } |
1778 | Worklist.swap(Pending); |
1779 | // At this point, pending must be empty, since it was just the empty |
1780 | // worklist |
1781 | assert(Pending.empty() && "Pending should be empty")((Pending.empty() && "Pending should be empty") ? static_cast <void> (0) : __assert_fail ("Pending.empty() && \"Pending should be empty\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1781, __PRETTY_FUNCTION__)); |
1782 | } |
1783 | |
1784 | // Add any DBG_VALUE instructions created by location transfers. |
1785 | for (auto &TR : Transfers) { |
1786 | assert(!TR.TransferInst->isTerminator() &&((!TR.TransferInst->isTerminator() && "Cannot insert DBG_VALUE after terminator" ) ? static_cast<void> (0) : __assert_fail ("!TR.TransferInst->isTerminator() && \"Cannot insert DBG_VALUE after terminator\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1787, __PRETTY_FUNCTION__)) |
1787 | "Cannot insert DBG_VALUE after terminator")((!TR.TransferInst->isTerminator() && "Cannot insert DBG_VALUE after terminator" ) ? static_cast<void> (0) : __assert_fail ("!TR.TransferInst->isTerminator() && \"Cannot insert DBG_VALUE after terminator\"" , "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/lib/CodeGen/LiveDebugValues.cpp" , 1787, __PRETTY_FUNCTION__)); |
1788 | MachineBasicBlock *MBB = TR.TransferInst->getParent(); |
1789 | const VarLoc &VL = VarLocIDs[TR.LocationID]; |
1790 | MachineInstr *MI = VL.BuildDbgValue(MF); |
1791 | MBB->insertAfterBundle(TR.TransferInst->getIterator(), MI); |
1792 | } |
1793 | Transfers.clear(); |
1794 | |
1795 | // Deferred inlocs will not have had any DBG_VALUE insts created; do |
1796 | // that now. |
1797 | flushPendingLocs(PendingInLocs, VarLocIDs); |
1798 | |
1799 | LLVM_DEBUG(printVarLocInMBB(MF, OutLocs, VarLocIDs, "Final OutLocs", dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, OutLocs, VarLocIDs , "Final OutLocs", dbgs()); } } while (false); |
1800 | LLVM_DEBUG(printVarLocInMBB(MF, InLocs, VarLocIDs, "Final InLocs", dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, InLocs, VarLocIDs , "Final InLocs", dbgs()); } } while (false); |
1801 | return Changed; |
1802 | } |
1803 | |
1804 | bool LiveDebugValues::runOnMachineFunction(MachineFunction &MF) { |
1805 | if (!MF.getFunction().getSubprogram()) |
1806 | // LiveDebugValues will already have removed all DBG_VALUEs. |
1807 | return false; |
1808 | |
1809 | // Skip functions from NoDebug compilation units. |
1810 | if (MF.getFunction().getSubprogram()->getUnit()->getEmissionKind() == |
1811 | DICompileUnit::NoDebug) |
1812 | return false; |
1813 | |
1814 | TRI = MF.getSubtarget().getRegisterInfo(); |
1815 | TII = MF.getSubtarget().getInstrInfo(); |
1816 | TFI = MF.getSubtarget().getFrameLowering(); |
1817 | TFI->getCalleeSaves(MF, CalleeSavedRegs); |
1818 | LS.initialize(MF); |
1819 | |
1820 | bool Changed = ExtendRanges(MF); |
1821 | return Changed; |
1822 | } |