File: | lib/CodeGen/LiveDebugValues.cpp |
Warning: | line 764, column 9 Value stored to 'MBBJoined' is never read |
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1 | //===- LiveDebugValues.cpp - Tracking Debug Value MIs ---------------------===// |
2 | // |
3 | // The LLVM Compiler Infrastructure |
4 | // |
5 | // This file is distributed under the University of Illinois Open Source |
6 | // License. See LICENSE.TXT for details. |
7 | // |
8 | //===----------------------------------------------------------------------===// |
9 | /// |
10 | /// This pass implements a data flow analysis that propagates debug location |
11 | /// information by inserting additional DBG_VALUE instructions into the machine |
12 | /// instruction stream. The pass internally builds debug location liveness |
13 | /// ranges to determine the points where additional DBG_VALUEs need to be |
14 | /// inserted. |
15 | /// |
16 | /// This is a separate pass from DbgValueHistoryCalculator to facilitate |
17 | /// testing and improve modularity. |
18 | /// |
19 | //===----------------------------------------------------------------------===// |
20 | |
21 | #include "llvm/ADT/DenseMap.h" |
22 | #include "llvm/ADT/PostOrderIterator.h" |
23 | #include "llvm/ADT/SmallPtrSet.h" |
24 | #include "llvm/ADT/SmallVector.h" |
25 | #include "llvm/ADT/SparseBitVector.h" |
26 | #include "llvm/ADT/Statistic.h" |
27 | #include "llvm/ADT/UniqueVector.h" |
28 | #include "llvm/CodeGen/LexicalScopes.h" |
29 | #include "llvm/CodeGen/MachineBasicBlock.h" |
30 | #include "llvm/CodeGen/MachineFrameInfo.h" |
31 | #include "llvm/CodeGen/MachineFunction.h" |
32 | #include "llvm/CodeGen/MachineFunctionPass.h" |
33 | #include "llvm/CodeGen/MachineInstr.h" |
34 | #include "llvm/CodeGen/MachineInstrBuilder.h" |
35 | #include "llvm/CodeGen/MachineMemOperand.h" |
36 | #include "llvm/CodeGen/MachineOperand.h" |
37 | #include "llvm/CodeGen/PseudoSourceValue.h" |
38 | #include "llvm/CodeGen/TargetFrameLowering.h" |
39 | #include "llvm/CodeGen/TargetInstrInfo.h" |
40 | #include "llvm/CodeGen/TargetLowering.h" |
41 | #include "llvm/CodeGen/TargetRegisterInfo.h" |
42 | #include "llvm/CodeGen/TargetSubtargetInfo.h" |
43 | #include "llvm/CodeGen/RegisterScavenging.h" |
44 | #include "llvm/Config/llvm-config.h" |
45 | #include "llvm/IR/DebugInfoMetadata.h" |
46 | #include "llvm/IR/DebugLoc.h" |
47 | #include "llvm/IR/Function.h" |
48 | #include "llvm/IR/Module.h" |
49 | #include "llvm/MC/MCRegisterInfo.h" |
50 | #include "llvm/Pass.h" |
51 | #include "llvm/Support/Casting.h" |
52 | #include "llvm/Support/Compiler.h" |
53 | #include "llvm/Support/Debug.h" |
54 | #include "llvm/Support/raw_ostream.h" |
55 | #include <algorithm> |
56 | #include <cassert> |
57 | #include <cstdint> |
58 | #include <functional> |
59 | #include <queue> |
60 | #include <utility> |
61 | #include <vector> |
62 | |
63 | using namespace llvm; |
64 | |
65 | #define DEBUG_TYPE"livedebugvalues" "livedebugvalues" |
66 | |
67 | STATISTIC(NumInserted, "Number of DBG_VALUE instructions inserted")static llvm::Statistic NumInserted = {"livedebugvalues", "NumInserted" , "Number of DBG_VALUE instructions inserted", {0}, {false}}; |
68 | |
69 | // If @MI is a DBG_VALUE with debug value described by a defined |
70 | // register, returns the number of this register. In the other case, returns 0. |
71 | static unsigned isDbgValueDescribedByReg(const MachineInstr &MI) { |
72 | assert(MI.isDebugValue() && "expected a DBG_VALUE")(static_cast <bool> (MI.isDebugValue() && "expected a DBG_VALUE" ) ? void (0) : __assert_fail ("MI.isDebugValue() && \"expected a DBG_VALUE\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 72, __extension__ __PRETTY_FUNCTION__)); |
73 | assert(MI.getNumOperands() == 4 && "malformed DBG_VALUE")(static_cast <bool> (MI.getNumOperands() == 4 && "malformed DBG_VALUE") ? void (0) : __assert_fail ("MI.getNumOperands() == 4 && \"malformed DBG_VALUE\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 73, __extension__ __PRETTY_FUNCTION__)); |
74 | // If location of variable is described using a register (directly |
75 | // or indirectly), this register is always a first operand. |
76 | return MI.getOperand(0).isReg() ? MI.getOperand(0).getReg() : 0; |
77 | } |
78 | |
79 | namespace { |
80 | |
81 | class LiveDebugValues : public MachineFunctionPass { |
82 | private: |
83 | const TargetRegisterInfo *TRI; |
84 | const TargetInstrInfo *TII; |
85 | const TargetFrameLowering *TFI; |
86 | BitVector CalleeSavedRegs; |
87 | LexicalScopes LS; |
88 | |
89 | /// Keeps track of lexical scopes associated with a user value's source |
90 | /// location. |
91 | class UserValueScopes { |
92 | DebugLoc DL; |
93 | LexicalScopes &LS; |
94 | SmallPtrSet<const MachineBasicBlock *, 4> LBlocks; |
95 | |
96 | public: |
97 | UserValueScopes(DebugLoc D, LexicalScopes &L) : DL(std::move(D)), LS(L) {} |
98 | |
99 | /// Return true if current scope dominates at least one machine |
100 | /// instruction in a given machine basic block. |
101 | bool dominates(MachineBasicBlock *MBB) { |
102 | if (LBlocks.empty()) |
103 | LS.getMachineBasicBlocks(DL, LBlocks); |
104 | return LBlocks.count(MBB) != 0 || LS.dominates(DL, MBB); |
105 | } |
106 | }; |
107 | |
108 | /// Based on std::pair so it can be used as an index into a DenseMap. |
109 | using DebugVariableBase = |
110 | std::pair<const DILocalVariable *, const DILocation *>; |
111 | /// A potentially inlined instance of a variable. |
112 | struct DebugVariable : public DebugVariableBase { |
113 | DebugVariable(const DILocalVariable *Var, const DILocation *InlinedAt) |
114 | : DebugVariableBase(Var, InlinedAt) {} |
115 | |
116 | const DILocalVariable *getVar() const { return this->first; } |
117 | const DILocation *getInlinedAt() const { return this->second; } |
118 | |
119 | bool operator<(const DebugVariable &DV) const { |
120 | if (getVar() == DV.getVar()) |
121 | return getInlinedAt() < DV.getInlinedAt(); |
122 | return getVar() < DV.getVar(); |
123 | } |
124 | }; |
125 | |
126 | /// A pair of debug variable and value location. |
127 | struct VarLoc { |
128 | const DebugVariable Var; |
129 | const MachineInstr &MI; ///< Only used for cloning a new DBG_VALUE. |
130 | mutable UserValueScopes UVS; |
131 | enum { InvalidKind = 0, RegisterKind } Kind = InvalidKind; |
132 | |
133 | /// The value location. Stored separately to avoid repeatedly |
134 | /// extracting it from MI. |
135 | union { |
136 | uint64_t RegNo; |
137 | uint64_t Hash; |
138 | } Loc; |
139 | |
140 | VarLoc(const MachineInstr &MI, LexicalScopes &LS) |
141 | : Var(MI.getDebugVariable(), MI.getDebugLoc()->getInlinedAt()), MI(MI), |
142 | UVS(MI.getDebugLoc(), LS) { |
143 | static_assert((sizeof(Loc) == sizeof(uint64_t)), |
144 | "hash does not cover all members of Loc"); |
145 | assert(MI.isDebugValue() && "not a DBG_VALUE")(static_cast <bool> (MI.isDebugValue() && "not a DBG_VALUE" ) ? void (0) : __assert_fail ("MI.isDebugValue() && \"not a DBG_VALUE\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 145, __extension__ __PRETTY_FUNCTION__)); |
146 | assert(MI.getNumOperands() == 4 && "malformed DBG_VALUE")(static_cast <bool> (MI.getNumOperands() == 4 && "malformed DBG_VALUE") ? void (0) : __assert_fail ("MI.getNumOperands() == 4 && \"malformed DBG_VALUE\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 146, __extension__ __PRETTY_FUNCTION__)); |
147 | if (int RegNo = isDbgValueDescribedByReg(MI)) { |
148 | Kind = RegisterKind; |
149 | Loc.RegNo = RegNo; |
150 | } |
151 | } |
152 | |
153 | /// If this variable is described by a register, return it, |
154 | /// otherwise return 0. |
155 | unsigned isDescribedByReg() const { |
156 | if (Kind == RegisterKind) |
157 | return Loc.RegNo; |
158 | return 0; |
159 | } |
160 | |
161 | /// Determine whether the lexical scope of this value's debug location |
162 | /// dominates MBB. |
163 | bool dominates(MachineBasicBlock &MBB) const { return UVS.dominates(&MBB); } |
164 | |
165 | #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) |
166 | LLVM_DUMP_METHOD__attribute__((noinline)) __attribute__((__used__)) void dump() const { MI.dump(); } |
167 | #endif |
168 | |
169 | bool operator==(const VarLoc &Other) const { |
170 | return Var == Other.Var && Loc.Hash == Other.Loc.Hash; |
171 | } |
172 | |
173 | /// This operator guarantees that VarLocs are sorted by Variable first. |
174 | bool operator<(const VarLoc &Other) const { |
175 | if (Var == Other.Var) |
176 | return Loc.Hash < Other.Loc.Hash; |
177 | return Var < Other.Var; |
178 | } |
179 | }; |
180 | |
181 | using VarLocMap = UniqueVector<VarLoc>; |
182 | using VarLocSet = SparseBitVector<>; |
183 | using VarLocInMBB = SmallDenseMap<const MachineBasicBlock *, VarLocSet>; |
184 | struct TransferDebugPair { |
185 | MachineInstr *TransferInst; |
186 | MachineInstr *DebugInst; |
187 | }; |
188 | using TransferMap = SmallVector<TransferDebugPair, 4>; |
189 | |
190 | /// This holds the working set of currently open ranges. For fast |
191 | /// access, this is done both as a set of VarLocIDs, and a map of |
192 | /// DebugVariable to recent VarLocID. Note that a DBG_VALUE ends all |
193 | /// previous open ranges for the same variable. |
194 | class OpenRangesSet { |
195 | VarLocSet VarLocs; |
196 | SmallDenseMap<DebugVariableBase, unsigned, 8> Vars; |
197 | |
198 | public: |
199 | const VarLocSet &getVarLocs() const { return VarLocs; } |
200 | |
201 | /// Terminate all open ranges for Var by removing it from the set. |
202 | void erase(DebugVariable Var) { |
203 | auto It = Vars.find(Var); |
204 | if (It != Vars.end()) { |
205 | unsigned ID = It->second; |
206 | VarLocs.reset(ID); |
207 | Vars.erase(It); |
208 | } |
209 | } |
210 | |
211 | /// Terminate all open ranges listed in \c KillSet by removing |
212 | /// them from the set. |
213 | void erase(const VarLocSet &KillSet, const VarLocMap &VarLocIDs) { |
214 | VarLocs.intersectWithComplement(KillSet); |
215 | for (unsigned ID : KillSet) |
216 | Vars.erase(VarLocIDs[ID].Var); |
217 | } |
218 | |
219 | /// Insert a new range into the set. |
220 | void insert(unsigned VarLocID, DebugVariableBase Var) { |
221 | VarLocs.set(VarLocID); |
222 | Vars.insert({Var, VarLocID}); |
223 | } |
224 | |
225 | /// Empty the set. |
226 | void clear() { |
227 | VarLocs.clear(); |
228 | Vars.clear(); |
229 | } |
230 | |
231 | /// Return whether the set is empty or not. |
232 | bool empty() const { |
233 | assert(Vars.empty() == VarLocs.empty() && "open ranges are inconsistent")(static_cast <bool> (Vars.empty() == VarLocs.empty() && "open ranges are inconsistent") ? void (0) : __assert_fail ( "Vars.empty() == VarLocs.empty() && \"open ranges are inconsistent\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 233, __extension__ __PRETTY_FUNCTION__)); |
234 | return VarLocs.empty(); |
235 | } |
236 | }; |
237 | |
238 | bool isSpillInstruction(const MachineInstr &MI, MachineFunction *MF, |
239 | unsigned &Reg); |
240 | int extractSpillBaseRegAndOffset(const MachineInstr &MI, unsigned &Reg); |
241 | void insertTransferDebugPair(MachineInstr &MI, OpenRangesSet &OpenRanges, |
242 | TransferMap &Transfers, VarLocMap &VarLocIDs, |
243 | unsigned OldVarID, unsigned NewReg = 0); |
244 | |
245 | void transferDebugValue(const MachineInstr &MI, OpenRangesSet &OpenRanges, |
246 | VarLocMap &VarLocIDs); |
247 | void transferSpillInst(MachineInstr &MI, OpenRangesSet &OpenRanges, |
248 | VarLocMap &VarLocIDs, TransferMap &Transfers); |
249 | void transferRegisterCopy(MachineInstr &MI, OpenRangesSet &OpenRanges, |
250 | VarLocMap &VarLocIDs, TransferMap &Transfers); |
251 | void transferRegisterDef(MachineInstr &MI, OpenRangesSet &OpenRanges, |
252 | const VarLocMap &VarLocIDs); |
253 | bool transferTerminatorInst(MachineInstr &MI, OpenRangesSet &OpenRanges, |
254 | VarLocInMBB &OutLocs, const VarLocMap &VarLocIDs); |
255 | bool process(MachineInstr &MI, OpenRangesSet &OpenRanges, |
256 | VarLocInMBB &OutLocs, VarLocMap &VarLocIDs, |
257 | TransferMap &Transfers, bool transferChanges); |
258 | |
259 | bool join(MachineBasicBlock &MBB, VarLocInMBB &OutLocs, VarLocInMBB &InLocs, |
260 | const VarLocMap &VarLocIDs, |
261 | SmallPtrSet<const MachineBasicBlock *, 16> &Visited); |
262 | |
263 | bool ExtendRanges(MachineFunction &MF); |
264 | |
265 | public: |
266 | static char ID; |
267 | |
268 | /// Default construct and initialize the pass. |
269 | LiveDebugValues(); |
270 | |
271 | /// Tell the pass manager which passes we depend on and what |
272 | /// information we preserve. |
273 | void getAnalysisUsage(AnalysisUsage &AU) const override; |
274 | |
275 | MachineFunctionProperties getRequiredProperties() const override { |
276 | return MachineFunctionProperties().set( |
277 | MachineFunctionProperties::Property::NoVRegs); |
278 | } |
279 | |
280 | /// Print to ostream with a message. |
281 | void printVarLocInMBB(const MachineFunction &MF, const VarLocInMBB &V, |
282 | const VarLocMap &VarLocIDs, const char *msg, |
283 | raw_ostream &Out) const; |
284 | |
285 | /// Calculate the liveness information for the given machine function. |
286 | bool runOnMachineFunction(MachineFunction &MF) override; |
287 | }; |
288 | |
289 | } // end anonymous namespace |
290 | |
291 | //===----------------------------------------------------------------------===// |
292 | // Implementation |
293 | //===----------------------------------------------------------------------===// |
294 | |
295 | char LiveDebugValues::ID = 0; |
296 | |
297 | char &llvm::LiveDebugValuesID = LiveDebugValues::ID; |
298 | |
299 | 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)); } |
300 | 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)); } |
301 | |
302 | /// Default construct and initialize the pass. |
303 | LiveDebugValues::LiveDebugValues() : MachineFunctionPass(ID) { |
304 | initializeLiveDebugValuesPass(*PassRegistry::getPassRegistry()); |
305 | } |
306 | |
307 | /// Tell the pass manager which passes we depend on and what information we |
308 | /// preserve. |
309 | void LiveDebugValues::getAnalysisUsage(AnalysisUsage &AU) const { |
310 | AU.setPreservesCFG(); |
311 | MachineFunctionPass::getAnalysisUsage(AU); |
312 | } |
313 | |
314 | //===----------------------------------------------------------------------===// |
315 | // Debug Range Extension Implementation |
316 | //===----------------------------------------------------------------------===// |
317 | |
318 | #ifndef NDEBUG |
319 | void LiveDebugValues::printVarLocInMBB(const MachineFunction &MF, |
320 | const VarLocInMBB &V, |
321 | const VarLocMap &VarLocIDs, |
322 | const char *msg, |
323 | raw_ostream &Out) const { |
324 | Out << '\n' << msg << '\n'; |
325 | for (const MachineBasicBlock &BB : MF) { |
326 | const auto &L = V.lookup(&BB); |
327 | Out << "MBB: " << BB.getName() << ":\n"; |
328 | for (unsigned VLL : L) { |
329 | const VarLoc &VL = VarLocIDs[VLL]; |
330 | Out << " Var: " << VL.Var.getVar()->getName(); |
331 | Out << " MI: "; |
332 | VL.dump(); |
333 | } |
334 | } |
335 | Out << "\n"; |
336 | } |
337 | #endif |
338 | |
339 | /// Given a spill instruction, extract the register and offset used to |
340 | /// address the spill location in a target independent way. |
341 | int LiveDebugValues::extractSpillBaseRegAndOffset(const MachineInstr &MI, |
342 | unsigned &Reg) { |
343 | assert(MI.hasOneMemOperand() &&(static_cast <bool> (MI.hasOneMemOperand() && "Spill instruction does not have exactly one memory operand?" ) ? void (0) : __assert_fail ("MI.hasOneMemOperand() && \"Spill instruction does not have exactly one memory operand?\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 344, __extension__ __PRETTY_FUNCTION__)) |
344 | "Spill instruction does not have exactly one memory operand?")(static_cast <bool> (MI.hasOneMemOperand() && "Spill instruction does not have exactly one memory operand?" ) ? void (0) : __assert_fail ("MI.hasOneMemOperand() && \"Spill instruction does not have exactly one memory operand?\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 344, __extension__ __PRETTY_FUNCTION__)); |
345 | auto MMOI = MI.memoperands_begin(); |
346 | const PseudoSourceValue *PVal = (*MMOI)->getPseudoValue(); |
347 | assert(PVal->kind() == PseudoSourceValue::FixedStack &&(static_cast <bool> (PVal->kind() == PseudoSourceValue ::FixedStack && "Inconsistent memory operand in spill instruction" ) ? void (0) : __assert_fail ("PVal->kind() == PseudoSourceValue::FixedStack && \"Inconsistent memory operand in spill instruction\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 348, __extension__ __PRETTY_FUNCTION__)) |
348 | "Inconsistent memory operand in spill instruction")(static_cast <bool> (PVal->kind() == PseudoSourceValue ::FixedStack && "Inconsistent memory operand in spill instruction" ) ? void (0) : __assert_fail ("PVal->kind() == PseudoSourceValue::FixedStack && \"Inconsistent memory operand in spill instruction\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 348, __extension__ __PRETTY_FUNCTION__)); |
349 | int FI = cast<FixedStackPseudoSourceValue>(PVal)->getFrameIndex(); |
350 | const MachineBasicBlock *MBB = MI.getParent(); |
351 | return TFI->getFrameIndexReference(*MBB->getParent(), FI, Reg); |
352 | } |
353 | |
354 | /// End all previous ranges related to @MI and start a new range from @MI |
355 | /// if it is a DBG_VALUE instr. |
356 | void LiveDebugValues::transferDebugValue(const MachineInstr &MI, |
357 | OpenRangesSet &OpenRanges, |
358 | VarLocMap &VarLocIDs) { |
359 | if (!MI.isDebugValue()) |
360 | return; |
361 | const DILocalVariable *Var = MI.getDebugVariable(); |
362 | const DILocation *DebugLoc = MI.getDebugLoc(); |
363 | const DILocation *InlinedAt = DebugLoc->getInlinedAt(); |
364 | assert(Var->isValidLocationForIntrinsic(DebugLoc) &&(static_cast <bool> (Var->isValidLocationForIntrinsic (DebugLoc) && "Expected inlined-at fields to agree") ? void (0) : __assert_fail ("Var->isValidLocationForIntrinsic(DebugLoc) && \"Expected inlined-at fields to agree\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 365, __extension__ __PRETTY_FUNCTION__)) |
365 | "Expected inlined-at fields to agree")(static_cast <bool> (Var->isValidLocationForIntrinsic (DebugLoc) && "Expected inlined-at fields to agree") ? void (0) : __assert_fail ("Var->isValidLocationForIntrinsic(DebugLoc) && \"Expected inlined-at fields to agree\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 365, __extension__ __PRETTY_FUNCTION__)); |
366 | |
367 | // End all previous ranges of Var. |
368 | DebugVariable V(Var, InlinedAt); |
369 | OpenRanges.erase(V); |
370 | |
371 | // Add the VarLoc to OpenRanges from this DBG_VALUE. |
372 | // TODO: Currently handles DBG_VALUE which has only reg as location. |
373 | if (isDbgValueDescribedByReg(MI)) { |
374 | VarLoc VL(MI, LS); |
375 | unsigned ID = VarLocIDs.insert(VL); |
376 | OpenRanges.insert(ID, VL.Var); |
377 | } |
378 | } |
379 | |
380 | /// Create new TransferDebugPair and insert it in \p Transfers. The VarLoc |
381 | /// with \p OldVarID should be deleted form \p OpenRanges and replaced with |
382 | /// new VarLoc. If \p NewReg is different than default zero value then the |
383 | /// new location will be register location created by the copy like instruction, |
384 | /// otherwise it is variable's location on the stack. |
385 | void LiveDebugValues::insertTransferDebugPair( |
386 | MachineInstr &MI, OpenRangesSet &OpenRanges, TransferMap &Transfers, |
387 | VarLocMap &VarLocIDs, unsigned OldVarID, unsigned NewReg) { |
388 | const MachineInstr *DMI = &VarLocIDs[OldVarID].MI; |
389 | MachineFunction *MF = MI.getParent()->getParent(); |
390 | MachineInstr *NewDMI; |
391 | if (NewReg) { |
392 | // Create a DBG_VALUE instruction to describe the Var in its new |
393 | // register location. |
394 | NewDMI = BuildMI(*MF, DMI->getDebugLoc(), DMI->getDesc(), |
395 | DMI->isIndirectDebugValue(), NewReg, |
396 | DMI->getDebugVariable(), DMI->getDebugExpression()); |
397 | if (DMI->isIndirectDebugValue()) |
398 | NewDMI->getOperand(1).setImm(DMI->getOperand(1).getImm()); |
399 | LLVM_DEBUG(dbgs() << "Creating DBG_VALUE inst for register copy: ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Creating DBG_VALUE inst for register copy: " ; NewDMI->print(dbgs(), false, false, false, TII); } } while (false) |
400 | NewDMI->print(dbgs(), false, false, false, TII))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Creating DBG_VALUE inst for register copy: " ; NewDMI->print(dbgs(), false, false, false, TII); } } while (false); |
401 | } else { |
402 | // Create a DBG_VALUE instruction to describe the Var in its spilled |
403 | // location. |
404 | unsigned SpillBase; |
405 | int SpillOffset = extractSpillBaseRegAndOffset(MI, SpillBase); |
406 | auto *SpillExpr = DIExpression::prepend(DMI->getDebugExpression(), |
407 | DIExpression::NoDeref, SpillOffset); |
408 | NewDMI = BuildMI(*MF, DMI->getDebugLoc(), DMI->getDesc(), true, SpillBase, |
409 | DMI->getDebugVariable(), SpillExpr); |
410 | LLVM_DEBUG(dbgs() << "Creating DBG_VALUE inst for spill: ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Creating DBG_VALUE inst for spill: " ; NewDMI->print(dbgs(), false, false, false, TII); } } while (false) |
411 | NewDMI->print(dbgs(), false, false, false, TII))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Creating DBG_VALUE inst for spill: " ; NewDMI->print(dbgs(), false, false, false, TII); } } while (false); |
412 | } |
413 | |
414 | // The newly created DBG_VALUE instruction NewDMI must be inserted after |
415 | // MI. Keep track of the pairing. |
416 | TransferDebugPair MIP = {&MI, NewDMI}; |
417 | Transfers.push_back(MIP); |
418 | |
419 | // End all previous ranges of Var. |
420 | OpenRanges.erase(VarLocIDs[OldVarID].Var); |
421 | |
422 | // Add the VarLoc to OpenRanges. |
423 | VarLoc VL(*NewDMI, LS); |
424 | unsigned LocID = VarLocIDs.insert(VL); |
425 | OpenRanges.insert(LocID, VL.Var); |
426 | } |
427 | |
428 | /// A definition of a register may mark the end of a range. |
429 | void LiveDebugValues::transferRegisterDef(MachineInstr &MI, |
430 | OpenRangesSet &OpenRanges, |
431 | const VarLocMap &VarLocIDs) { |
432 | MachineFunction *MF = MI.getMF(); |
433 | const TargetLowering *TLI = MF->getSubtarget().getTargetLowering(); |
434 | unsigned SP = TLI->getStackPointerRegisterToSaveRestore(); |
435 | SparseBitVector<> KillSet; |
436 | for (const MachineOperand &MO : MI.operands()) { |
437 | // Determine whether the operand is a register def. Assume that call |
438 | // instructions never clobber SP, because some backends (e.g., AArch64) |
439 | // never list SP in the regmask. |
440 | if (MO.isReg() && MO.isDef() && MO.getReg() && |
441 | TRI->isPhysicalRegister(MO.getReg()) && |
442 | !(MI.isCall() && MO.getReg() == SP)) { |
443 | // Remove ranges of all aliased registers. |
444 | for (MCRegAliasIterator RAI(MO.getReg(), TRI, true); RAI.isValid(); ++RAI) |
445 | for (unsigned ID : OpenRanges.getVarLocs()) |
446 | if (VarLocIDs[ID].isDescribedByReg() == *RAI) |
447 | KillSet.set(ID); |
448 | } else if (MO.isRegMask()) { |
449 | // Remove ranges of all clobbered registers. Register masks don't usually |
450 | // list SP as preserved. While the debug info may be off for an |
451 | // instruction or two around callee-cleanup calls, transferring the |
452 | // DEBUG_VALUE across the call is still a better user experience. |
453 | for (unsigned ID : OpenRanges.getVarLocs()) { |
454 | unsigned Reg = VarLocIDs[ID].isDescribedByReg(); |
455 | if (Reg && Reg != SP && MO.clobbersPhysReg(Reg)) |
456 | KillSet.set(ID); |
457 | } |
458 | } |
459 | } |
460 | OpenRanges.erase(KillSet, VarLocIDs); |
461 | } |
462 | |
463 | /// Decide if @MI is a spill instruction and return true if it is. We use 2 |
464 | /// criteria to make this decision: |
465 | /// - Is this instruction a store to a spill slot? |
466 | /// - Is there a register operand that is both used and killed? |
467 | /// TODO: Store optimization can fold spills into other stores (including |
468 | /// other spills). We do not handle this yet (more than one memory operand). |
469 | bool LiveDebugValues::isSpillInstruction(const MachineInstr &MI, |
470 | MachineFunction *MF, unsigned &Reg) { |
471 | const MachineFrameInfo &FrameInfo = MF->getFrameInfo(); |
472 | int FI; |
473 | const MachineMemOperand *MMO; |
474 | |
475 | // TODO: Handle multiple stores folded into one. |
476 | if (!MI.hasOneMemOperand()) |
477 | return false; |
478 | |
479 | // To identify a spill instruction, use the same criteria as in AsmPrinter. |
480 | if (!((TII->isStoreToStackSlotPostFE(MI, FI) || |
481 | TII->hasStoreToStackSlot(MI, MMO, FI)) && |
482 | FrameInfo.isSpillSlotObjectIndex(FI))) |
483 | return false; |
484 | |
485 | auto isKilledReg = [&](const MachineOperand MO, unsigned &Reg) { |
486 | if (!MO.isReg() || !MO.isUse()) { |
487 | Reg = 0; |
488 | return false; |
489 | } |
490 | Reg = MO.getReg(); |
491 | return MO.isKill(); |
492 | }; |
493 | |
494 | for (const MachineOperand &MO : MI.operands()) { |
495 | // In a spill instruction generated by the InlineSpiller the spilled |
496 | // register has its kill flag set. |
497 | if (isKilledReg(MO, Reg)) |
498 | return true; |
499 | if (Reg != 0) { |
500 | // Check whether next instruction kills the spilled register. |
501 | // FIXME: Current solution does not cover search for killed register in |
502 | // bundles and instructions further down the chain. |
503 | auto NextI = std::next(MI.getIterator()); |
504 | // Skip next instruction that points to basic block end iterator. |
505 | if (MI.getParent()->end() == NextI) |
506 | continue; |
507 | unsigned RegNext; |
508 | for (const MachineOperand &MONext : NextI->operands()) { |
509 | // Return true if we came across the register from the |
510 | // previous spill instruction that is killed in NextI. |
511 | if (isKilledReg(MONext, RegNext) && RegNext == Reg) |
512 | return true; |
513 | } |
514 | } |
515 | } |
516 | // Return false if we didn't find spilled register. |
517 | return false; |
518 | } |
519 | |
520 | /// A spilled register may indicate that we have to end the current range of |
521 | /// a variable and create a new one for the spill location. |
522 | /// We don't want to insert any instructions in process(), so we just create |
523 | /// the DBG_VALUE without inserting it and keep track of it in \p Transfers. |
524 | /// It will be inserted into the BB when we're done iterating over the |
525 | /// instructions. |
526 | void LiveDebugValues::transferSpillInst(MachineInstr &MI, |
527 | OpenRangesSet &OpenRanges, |
528 | VarLocMap &VarLocIDs, |
529 | TransferMap &Transfers) { |
530 | unsigned Reg; |
531 | MachineFunction *MF = MI.getMF(); |
532 | if (!isSpillInstruction(MI, MF, Reg)) |
533 | return; |
534 | |
535 | // Check if the register is the location of a debug value. |
536 | for (unsigned ID : OpenRanges.getVarLocs()) { |
537 | if (VarLocIDs[ID].isDescribedByReg() == Reg) { |
538 | LLVM_DEBUG(dbgs() << "Spilling Register " << printReg(Reg, TRI) << '('do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Spilling Register " << printReg(Reg, TRI) << '(' << VarLocIDs[ID].Var.getVar ()->getName() << ")\n"; } } while (false) |
539 | << VarLocIDs[ID].Var.getVar()->getName() << ")\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Spilling Register " << printReg(Reg, TRI) << '(' << VarLocIDs[ID].Var.getVar ()->getName() << ")\n"; } } while (false); |
540 | insertTransferDebugPair(MI, OpenRanges, Transfers, VarLocIDs, ID); |
541 | return; |
542 | } |
543 | } |
544 | } |
545 | |
546 | /// If \p MI is a register copy instruction, that copies a previously tracked |
547 | /// value from one register to another register that is callee saved, we |
548 | /// create new DBG_VALUE instruction described with copy destination register. |
549 | void LiveDebugValues::transferRegisterCopy(MachineInstr &MI, |
550 | OpenRangesSet &OpenRanges, |
551 | VarLocMap &VarLocIDs, |
552 | TransferMap &Transfers) { |
553 | const MachineOperand *SrcRegOp, *DestRegOp; |
554 | |
555 | if (!TII->isCopyInstr(MI, SrcRegOp, DestRegOp) || !SrcRegOp->isKill() || |
556 | !DestRegOp->isDef()) |
557 | return; |
558 | |
559 | auto isCalleSavedReg = [&](unsigned Reg) { |
560 | for (MCRegAliasIterator RAI(Reg, TRI, true); RAI.isValid(); ++RAI) |
561 | if (CalleeSavedRegs.test(*RAI)) |
562 | return true; |
563 | return false; |
564 | }; |
565 | |
566 | unsigned SrcReg = SrcRegOp->getReg(); |
567 | unsigned DestReg = DestRegOp->getReg(); |
568 | |
569 | // We want to recognize instructions where destination register is callee |
570 | // saved register. If register that could be clobbered by the call is |
571 | // included, there would be a great chance that it is going to be clobbered |
572 | // soon. It is more likely that previous register location, which is callee |
573 | // saved, is going to stay unclobbered longer, even if it is killed. |
574 | if (!isCalleSavedReg(DestReg)) |
575 | return; |
576 | |
577 | for (unsigned ID : OpenRanges.getVarLocs()) { |
578 | if (VarLocIDs[ID].isDescribedByReg() == SrcReg) { |
579 | insertTransferDebugPair(MI, OpenRanges, Transfers, VarLocIDs, ID, |
580 | DestReg); |
581 | return; |
582 | } |
583 | } |
584 | } |
585 | |
586 | /// Terminate all open ranges at the end of the current basic block. |
587 | bool LiveDebugValues::transferTerminatorInst(MachineInstr &MI, |
588 | OpenRangesSet &OpenRanges, |
589 | VarLocInMBB &OutLocs, |
590 | const VarLocMap &VarLocIDs) { |
591 | bool Changed = false; |
592 | const MachineBasicBlock *CurMBB = MI.getParent(); |
593 | if (!(MI.isTerminator() || (&MI == &CurMBB->back()))) |
594 | return false; |
595 | |
596 | if (OpenRanges.empty()) |
597 | return false; |
598 | |
599 | LLVM_DEBUG(for (unsigned IDdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (unsigned ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs: "; VarLocIDs[ID].dump( ); }; } } while (false) |
600 | : OpenRanges.getVarLocs()) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (unsigned ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs: "; VarLocIDs[ID].dump( ); }; } } while (false) |
601 | // Copy OpenRanges to OutLocs, if not already present.do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (unsigned ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs: "; VarLocIDs[ID].dump( ); }; } } while (false) |
602 | dbgs() << "Add to OutLocs: ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (unsigned ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs: "; VarLocIDs[ID].dump( ); }; } } while (false) |
603 | VarLocIDs[ID].dump();do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (unsigned ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs: "; VarLocIDs[ID].dump( ); }; } } while (false) |
604 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { for (unsigned ID : OpenRanges.getVarLocs ()) { dbgs() << "Add to OutLocs: "; VarLocIDs[ID].dump( ); }; } } while (false); |
605 | VarLocSet &VLS = OutLocs[CurMBB]; |
606 | Changed = VLS |= OpenRanges.getVarLocs(); |
607 | OpenRanges.clear(); |
608 | return Changed; |
609 | } |
610 | |
611 | /// This routine creates OpenRanges and OutLocs. |
612 | bool LiveDebugValues::process(MachineInstr &MI, OpenRangesSet &OpenRanges, |
613 | VarLocInMBB &OutLocs, VarLocMap &VarLocIDs, |
614 | TransferMap &Transfers, bool transferChanges) { |
615 | bool Changed = false; |
616 | transferDebugValue(MI, OpenRanges, VarLocIDs); |
617 | transferRegisterDef(MI, OpenRanges, VarLocIDs); |
618 | if (transferChanges) { |
619 | transferRegisterCopy(MI, OpenRanges, VarLocIDs, Transfers); |
620 | transferSpillInst(MI, OpenRanges, VarLocIDs, Transfers); |
621 | } |
622 | Changed = transferTerminatorInst(MI, OpenRanges, OutLocs, VarLocIDs); |
623 | return Changed; |
624 | } |
625 | |
626 | /// This routine joins the analysis results of all incoming edges in @MBB by |
627 | /// inserting a new DBG_VALUE instruction at the start of the @MBB - if the same |
628 | /// source variable in all the predecessors of @MBB reside in the same location. |
629 | bool LiveDebugValues::join(MachineBasicBlock &MBB, VarLocInMBB &OutLocs, |
630 | VarLocInMBB &InLocs, const VarLocMap &VarLocIDs, |
631 | SmallPtrSet<const MachineBasicBlock *, 16> &Visited) { |
632 | LLVM_DEBUG(dbgs() << "join MBB: " << MBB.getName() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "join MBB: " << MBB .getName() << "\n"; } } while (false); |
633 | bool Changed = false; |
634 | |
635 | VarLocSet InLocsT; // Temporary incoming locations. |
636 | |
637 | // For all predecessors of this MBB, find the set of VarLocs that |
638 | // can be joined. |
639 | int NumVisited = 0; |
640 | for (auto p : MBB.predecessors()) { |
641 | // Ignore unvisited predecessor blocks. As we are processing |
642 | // the blocks in reverse post-order any unvisited block can |
643 | // be considered to not remove any incoming values. |
644 | if (!Visited.count(p)) |
645 | continue; |
646 | auto OL = OutLocs.find(p); |
647 | // Join is null in case of empty OutLocs from any of the pred. |
648 | if (OL == OutLocs.end()) |
649 | return false; |
650 | |
651 | // Just copy over the Out locs to incoming locs for the first visited |
652 | // predecessor, and for all other predecessors join the Out locs. |
653 | if (!NumVisited) |
654 | InLocsT = OL->second; |
655 | else |
656 | InLocsT &= OL->second; |
657 | NumVisited++; |
658 | } |
659 | |
660 | // Filter out DBG_VALUES that are out of scope. |
661 | VarLocSet KillSet; |
662 | for (auto ID : InLocsT) |
663 | if (!VarLocIDs[ID].dominates(MBB)) |
664 | KillSet.set(ID); |
665 | InLocsT.intersectWithComplement(KillSet); |
666 | |
667 | // As we are processing blocks in reverse post-order we |
668 | // should have processed at least one predecessor, unless it |
669 | // is the entry block which has no predecessor. |
670 | assert((NumVisited || MBB.pred_empty()) &&(static_cast <bool> ((NumVisited || MBB.pred_empty()) && "Should have processed at least one predecessor") ? void (0) : __assert_fail ("(NumVisited || MBB.pred_empty()) && \"Should have processed at least one predecessor\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 671, __extension__ __PRETTY_FUNCTION__)) |
671 | "Should have processed at least one predecessor")(static_cast <bool> ((NumVisited || MBB.pred_empty()) && "Should have processed at least one predecessor") ? void (0) : __assert_fail ("(NumVisited || MBB.pred_empty()) && \"Should have processed at least one predecessor\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 671, __extension__ __PRETTY_FUNCTION__)); |
672 | if (InLocsT.empty()) |
673 | return false; |
674 | |
675 | VarLocSet &ILS = InLocs[&MBB]; |
676 | |
677 | // Insert DBG_VALUE instructions, if not already inserted. |
678 | VarLocSet Diff = InLocsT; |
679 | Diff.intersectWithComplement(ILS); |
680 | for (auto ID : Diff) { |
681 | // This VarLoc is not found in InLocs i.e. it is not yet inserted. So, a |
682 | // new range is started for the var from the mbb's beginning by inserting |
683 | // a new DBG_VALUE. process() will end this range however appropriate. |
684 | const VarLoc &DiffIt = VarLocIDs[ID]; |
685 | const MachineInstr *DMI = &DiffIt.MI; |
686 | MachineInstr *MI = |
687 | BuildMI(MBB, MBB.instr_begin(), DMI->getDebugLoc(), DMI->getDesc(), |
688 | DMI->isIndirectDebugValue(), DMI->getOperand(0).getReg(), |
689 | DMI->getDebugVariable(), DMI->getDebugExpression()); |
690 | if (DMI->isIndirectDebugValue()) |
691 | MI->getOperand(1).setImm(DMI->getOperand(1).getImm()); |
692 | LLVM_DEBUG(dbgs() << "Inserted: "; MI->dump();)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Inserted: "; MI->dump ();; } } while (false); |
693 | ILS.set(ID); |
694 | ++NumInserted; |
695 | Changed = true; |
696 | } |
697 | return Changed; |
698 | } |
699 | |
700 | /// Calculate the liveness information for the given machine function and |
701 | /// extend ranges across basic blocks. |
702 | bool LiveDebugValues::ExtendRanges(MachineFunction &MF) { |
703 | LLVM_DEBUG(dbgs() << "\nDebug Range Extension\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "\nDebug Range Extension\n" ; } } while (false); |
704 | |
705 | bool Changed = false; |
706 | bool OLChanged = false; |
707 | bool MBBJoined = false; |
708 | |
709 | VarLocMap VarLocIDs; // Map VarLoc<>unique ID for use in bitvectors. |
710 | OpenRangesSet OpenRanges; // Ranges that are open until end of bb. |
711 | VarLocInMBB OutLocs; // Ranges that exist beyond bb. |
712 | VarLocInMBB InLocs; // Ranges that are incoming after joining. |
713 | TransferMap Transfers; // DBG_VALUEs associated with spills. |
714 | |
715 | DenseMap<unsigned int, MachineBasicBlock *> OrderToBB; |
716 | DenseMap<MachineBasicBlock *, unsigned int> BBToOrder; |
717 | std::priority_queue<unsigned int, std::vector<unsigned int>, |
718 | std::greater<unsigned int>> |
719 | Worklist; |
720 | std::priority_queue<unsigned int, std::vector<unsigned int>, |
721 | std::greater<unsigned int>> |
722 | Pending; |
723 | |
724 | enum : bool { dontTransferChanges = false, transferChanges = true }; |
725 | |
726 | // Initialize every mbb with OutLocs. |
727 | // We are not looking at any spill instructions during the initial pass |
728 | // over the BBs. The LiveDebugVariables pass has already created DBG_VALUE |
729 | // instructions for spills of registers that are known to be user variables |
730 | // within the BB in which the spill occurs. |
731 | for (auto &MBB : MF) |
732 | for (auto &MI : MBB) |
733 | process(MI, OpenRanges, OutLocs, VarLocIDs, Transfers, |
734 | dontTransferChanges); |
735 | |
736 | LLVM_DEBUG(printVarLocInMBB(MF, OutLocs, VarLocIDs,do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, OutLocs, VarLocIDs , "OutLocs after initialization", dbgs()); } } while (false) |
737 | "OutLocs after initialization", dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, OutLocs, VarLocIDs , "OutLocs after initialization", dbgs()); } } while (false); |
738 | |
739 | ReversePostOrderTraversal<MachineFunction *> RPOT(&MF); |
740 | unsigned int RPONumber = 0; |
741 | for (auto RI = RPOT.begin(), RE = RPOT.end(); RI != RE; ++RI) { |
742 | OrderToBB[RPONumber] = *RI; |
743 | BBToOrder[*RI] = RPONumber; |
744 | Worklist.push(RPONumber); |
745 | ++RPONumber; |
746 | } |
747 | // This is a standard "union of predecessor outs" dataflow problem. |
748 | // To solve it, we perform join() and process() using the two worklist method |
749 | // until the ranges converge. |
750 | // Ranges have converged when both worklists are empty. |
751 | SmallPtrSet<const MachineBasicBlock *, 16> Visited; |
752 | while (!Worklist.empty() || !Pending.empty()) { |
753 | // We track what is on the pending worklist to avoid inserting the same |
754 | // thing twice. We could avoid this with a custom priority queue, but this |
755 | // is probably not worth it. |
756 | SmallPtrSet<MachineBasicBlock *, 16> OnPending; |
757 | LLVM_DEBUG(dbgs() << "Processing Worklist\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { dbgs() << "Processing Worklist\n" ; } } while (false); |
758 | while (!Worklist.empty()) { |
759 | MachineBasicBlock *MBB = OrderToBB[Worklist.top()]; |
760 | Worklist.pop(); |
761 | MBBJoined = join(*MBB, OutLocs, InLocs, VarLocIDs, Visited); |
762 | Visited.insert(MBB); |
763 | if (MBBJoined) { |
764 | MBBJoined = false; |
Value stored to 'MBBJoined' is never read | |
765 | Changed = true; |
766 | // Now that we have started to extend ranges across BBs we need to |
767 | // examine spill instructions to see whether they spill registers that |
768 | // correspond to user variables. |
769 | for (auto &MI : *MBB) |
770 | OLChanged |= process(MI, OpenRanges, OutLocs, VarLocIDs, Transfers, |
771 | transferChanges); |
772 | |
773 | // Add any DBG_VALUE instructions necessitated by spills. |
774 | for (auto &TR : Transfers) |
775 | MBB->insertAfter(MachineBasicBlock::iterator(*TR.TransferInst), |
776 | TR.DebugInst); |
777 | Transfers.clear(); |
778 | |
779 | LLVM_DEBUG(printVarLocInMBB(MF, OutLocs, VarLocIDs,do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, OutLocs, VarLocIDs , "OutLocs after propagating", dbgs()); } } while (false) |
780 | "OutLocs after propagating", dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, OutLocs, VarLocIDs , "OutLocs after propagating", dbgs()); } } while (false); |
781 | LLVM_DEBUG(printVarLocInMBB(MF, InLocs, VarLocIDs,do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, InLocs, VarLocIDs , "InLocs after propagating", dbgs()); } } while (false) |
782 | "InLocs after propagating", dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvalues")) { printVarLocInMBB(MF, InLocs, VarLocIDs , "InLocs after propagating", dbgs()); } } while (false); |
783 | |
784 | if (OLChanged) { |
785 | OLChanged = false; |
786 | for (auto s : MBB->successors()) |
787 | if (OnPending.insert(s).second) { |
788 | Pending.push(BBToOrder[s]); |
789 | } |
790 | } |
791 | } |
792 | } |
793 | Worklist.swap(Pending); |
794 | // At this point, pending must be empty, since it was just the empty |
795 | // worklist |
796 | assert(Pending.empty() && "Pending should be empty")(static_cast <bool> (Pending.empty() && "Pending should be empty" ) ? void (0) : __assert_fail ("Pending.empty() && \"Pending should be empty\"" , "/build/llvm-toolchain-snapshot-7~svn338205/lib/CodeGen/LiveDebugValues.cpp" , 796, __extension__ __PRETTY_FUNCTION__)); |
797 | } |
798 | |
799 | 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); |
800 | 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); |
801 | return Changed; |
802 | } |
803 | |
804 | bool LiveDebugValues::runOnMachineFunction(MachineFunction &MF) { |
805 | if (!MF.getFunction().getSubprogram()) |
806 | // LiveDebugValues will already have removed all DBG_VALUEs. |
807 | return false; |
808 | |
809 | // Skip functions from NoDebug compilation units. |
810 | if (MF.getFunction().getSubprogram()->getUnit()->getEmissionKind() == |
811 | DICompileUnit::NoDebug) |
812 | return false; |
813 | |
814 | TRI = MF.getSubtarget().getRegisterInfo(); |
815 | TII = MF.getSubtarget().getInstrInfo(); |
816 | TFI = MF.getSubtarget().getFrameLowering(); |
817 | TFI->determineCalleeSaves(MF, CalleeSavedRegs, |
818 | make_unique<RegScavenger>().get()); |
819 | LS.initialize(MF); |
820 | |
821 | bool Changed = ExtendRanges(MF); |
822 | return Changed; |
823 | } |