| File: | llvm/lib/CodeGen/LiveDebugVariables.cpp |
| Warning: | line 518, column 5 1st function call argument is an uninitialized value |
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| 1 | //===- LiveDebugVariables.cpp - Tracking debug info variables -------------===// | |||
| 2 | // | |||
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | |||
| 4 | // See https://llvm.org/LICENSE.txt for license information. | |||
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | |||
| 6 | // | |||
| 7 | //===----------------------------------------------------------------------===// | |||
| 8 | // | |||
| 9 | // This file implements the LiveDebugVariables analysis. | |||
| 10 | // | |||
| 11 | // Remove all DBG_VALUE instructions referencing virtual registers and replace | |||
| 12 | // them with a data structure tracking where live user variables are kept - in a | |||
| 13 | // virtual register or in a stack slot. | |||
| 14 | // | |||
| 15 | // Allow the data structure to be updated during register allocation when values | |||
| 16 | // are moved between registers and stack slots. Finally emit new DBG_VALUE | |||
| 17 | // instructions after register allocation is complete. | |||
| 18 | // | |||
| 19 | //===----------------------------------------------------------------------===// | |||
| 20 | ||||
| 21 | #include "LiveDebugVariables.h" | |||
| 22 | #include "llvm/ADT/ArrayRef.h" | |||
| 23 | #include "llvm/ADT/DenseMap.h" | |||
| 24 | #include "llvm/ADT/IntervalMap.h" | |||
| 25 | #include "llvm/ADT/MapVector.h" | |||
| 26 | #include "llvm/ADT/STLExtras.h" | |||
| 27 | #include "llvm/ADT/SmallSet.h" | |||
| 28 | #include "llvm/ADT/SmallVector.h" | |||
| 29 | #include "llvm/ADT/Statistic.h" | |||
| 30 | #include "llvm/ADT/StringRef.h" | |||
| 31 | #include "llvm/CodeGen/LexicalScopes.h" | |||
| 32 | #include "llvm/CodeGen/LiveInterval.h" | |||
| 33 | #include "llvm/CodeGen/LiveIntervals.h" | |||
| 34 | #include "llvm/CodeGen/MachineBasicBlock.h" | |||
| 35 | #include "llvm/CodeGen/MachineDominators.h" | |||
| 36 | #include "llvm/CodeGen/MachineFunction.h" | |||
| 37 | #include "llvm/CodeGen/MachineInstr.h" | |||
| 38 | #include "llvm/CodeGen/MachineInstrBuilder.h" | |||
| 39 | #include "llvm/CodeGen/MachineOperand.h" | |||
| 40 | #include "llvm/CodeGen/MachineRegisterInfo.h" | |||
| 41 | #include "llvm/CodeGen/SlotIndexes.h" | |||
| 42 | #include "llvm/CodeGen/TargetInstrInfo.h" | |||
| 43 | #include "llvm/CodeGen/TargetOpcodes.h" | |||
| 44 | #include "llvm/CodeGen/TargetRegisterInfo.h" | |||
| 45 | #include "llvm/CodeGen/TargetSubtargetInfo.h" | |||
| 46 | #include "llvm/CodeGen/VirtRegMap.h" | |||
| 47 | #include "llvm/Config/llvm-config.h" | |||
| 48 | #include "llvm/IR/DebugInfoMetadata.h" | |||
| 49 | #include "llvm/IR/DebugLoc.h" | |||
| 50 | #include "llvm/IR/Function.h" | |||
| 51 | #include "llvm/IR/Metadata.h" | |||
| 52 | #include "llvm/MC/MCRegisterInfo.h" | |||
| 53 | #include "llvm/Pass.h" | |||
| 54 | #include "llvm/Support/Casting.h" | |||
| 55 | #include "llvm/Support/CommandLine.h" | |||
| 56 | #include "llvm/Support/Compiler.h" | |||
| 57 | #include "llvm/Support/Debug.h" | |||
| 58 | #include "llvm/Support/raw_ostream.h" | |||
| 59 | #include <algorithm> | |||
| 60 | #include <cassert> | |||
| 61 | #include <iterator> | |||
| 62 | #include <memory> | |||
| 63 | #include <utility> | |||
| 64 | ||||
| 65 | using namespace llvm; | |||
| 66 | ||||
| 67 | #define DEBUG_TYPE"livedebugvars" "livedebugvars" | |||
| 68 | ||||
| 69 | static cl::opt<bool> | |||
| 70 | EnableLDV("live-debug-variables", cl::init(true), | |||
| 71 | cl::desc("Enable the live debug variables pass"), cl::Hidden); | |||
| 72 | ||||
| 73 | STATISTIC(NumInsertedDebugValues, "Number of DBG_VALUEs inserted")static llvm::Statistic NumInsertedDebugValues = {"livedebugvars" , "NumInsertedDebugValues", "Number of DBG_VALUEs inserted"}; | |||
| 74 | STATISTIC(NumInsertedDebugLabels, "Number of DBG_LABELs inserted")static llvm::Statistic NumInsertedDebugLabels = {"livedebugvars" , "NumInsertedDebugLabels", "Number of DBG_LABELs inserted"}; | |||
| 75 | ||||
| 76 | char LiveDebugVariables::ID = 0; | |||
| 77 | ||||
| 78 | INITIALIZE_PASS_BEGIN(LiveDebugVariables, DEBUG_TYPE,static void *initializeLiveDebugVariablesPassOnce(PassRegistry &Registry) { | |||
| 79 | "Debug Variable Analysis", false, false)static void *initializeLiveDebugVariablesPassOnce(PassRegistry &Registry) { | |||
| 80 | INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)initializeMachineDominatorTreePass(Registry); | |||
| 81 | INITIALIZE_PASS_DEPENDENCY(LiveIntervals)initializeLiveIntervalsPass(Registry); | |||
| 82 | INITIALIZE_PASS_END(LiveDebugVariables, DEBUG_TYPE,PassInfo *PI = new PassInfo( "Debug Variable Analysis", "livedebugvars" , &LiveDebugVariables::ID, PassInfo::NormalCtor_t(callDefaultCtor <LiveDebugVariables>), false, false); Registry.registerPass (*PI, true); return PI; } static llvm::once_flag InitializeLiveDebugVariablesPassFlag ; void llvm::initializeLiveDebugVariablesPass(PassRegistry & Registry) { llvm::call_once(InitializeLiveDebugVariablesPassFlag , initializeLiveDebugVariablesPassOnce, std::ref(Registry)); } | |||
| 83 | "Debug Variable Analysis", false, false)PassInfo *PI = new PassInfo( "Debug Variable Analysis", "livedebugvars" , &LiveDebugVariables::ID, PassInfo::NormalCtor_t(callDefaultCtor <LiveDebugVariables>), false, false); Registry.registerPass (*PI, true); return PI; } static llvm::once_flag InitializeLiveDebugVariablesPassFlag ; void llvm::initializeLiveDebugVariablesPass(PassRegistry & Registry) { llvm::call_once(InitializeLiveDebugVariablesPassFlag , initializeLiveDebugVariablesPassOnce, std::ref(Registry)); } | |||
| 84 | ||||
| 85 | void LiveDebugVariables::getAnalysisUsage(AnalysisUsage &AU) const { | |||
| 86 | AU.addRequired<MachineDominatorTree>(); | |||
| 87 | AU.addRequiredTransitive<LiveIntervals>(); | |||
| 88 | AU.setPreservesAll(); | |||
| 89 | MachineFunctionPass::getAnalysisUsage(AU); | |||
| 90 | } | |||
| 91 | ||||
| 92 | LiveDebugVariables::LiveDebugVariables() : MachineFunctionPass(ID) { | |||
| 93 | initializeLiveDebugVariablesPass(*PassRegistry::getPassRegistry()); | |||
| 94 | } | |||
| 95 | ||||
| 96 | enum : unsigned { UndefLocNo = ~0U }; | |||
| 97 | ||||
| 98 | /// Describes a location by number along with some flags about the original | |||
| 99 | /// usage of the location. | |||
| 100 | class DbgValueLocation { | |||
| 101 | public: | |||
| 102 | DbgValueLocation(unsigned LocNo) | |||
| 103 | : LocNo(LocNo) { | |||
| 104 | static_assert(sizeof(*this) == sizeof(unsigned), "bad bitfield packing"); | |||
| 105 | assert(locNo() == LocNo && "location truncation")((locNo() == LocNo && "location truncation") ? static_cast <void> (0) : __assert_fail ("locNo() == LocNo && \"location truncation\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 105, __PRETTY_FUNCTION__)); | |||
| 106 | } | |||
| 107 | ||||
| 108 | DbgValueLocation() : LocNo(0) {} | |||
| 109 | ||||
| 110 | unsigned locNo() const { | |||
| 111 | // Fix up the undef location number, which gets truncated. | |||
| 112 | return LocNo == INT_MAX2147483647 ? UndefLocNo : LocNo; | |||
| 113 | } | |||
| 114 | bool isUndef() const { return locNo() == UndefLocNo; } | |||
| 115 | ||||
| 116 | DbgValueLocation changeLocNo(unsigned NewLocNo) const { | |||
| 117 | return DbgValueLocation(NewLocNo); | |||
| 118 | } | |||
| 119 | ||||
| 120 | friend inline bool operator==(const DbgValueLocation &LHS, | |||
| 121 | const DbgValueLocation &RHS) { | |||
| 122 | return LHS.LocNo == RHS.LocNo; | |||
| 123 | } | |||
| 124 | ||||
| 125 | friend inline bool operator!=(const DbgValueLocation &LHS, | |||
| 126 | const DbgValueLocation &RHS) { | |||
| 127 | return !(LHS == RHS); | |||
| 128 | } | |||
| 129 | ||||
| 130 | private: | |||
| 131 | unsigned LocNo; | |||
| 132 | }; | |||
| 133 | ||||
| 134 | /// Map of where a user value is live, and its location. | |||
| 135 | using LocMap = IntervalMap<SlotIndex, DbgValueLocation, 4>; | |||
| 136 | ||||
| 137 | /// Map of stack slot offsets for spilled locations. | |||
| 138 | /// Non-spilled locations are not added to the map. | |||
| 139 | using SpillOffsetMap = DenseMap<unsigned, unsigned>; | |||
| 140 | ||||
| 141 | namespace { | |||
| 142 | ||||
| 143 | class LDVImpl; | |||
| 144 | ||||
| 145 | /// A user value is a part of a debug info user variable. | |||
| 146 | /// | |||
| 147 | /// A DBG_VALUE instruction notes that (a sub-register of) a virtual register | |||
| 148 | /// holds part of a user variable. The part is identified by a byte offset. | |||
| 149 | /// | |||
| 150 | /// UserValues are grouped into equivalence classes for easier searching. Two | |||
| 151 | /// user values are related if they refer to the same variable, or if they are | |||
| 152 | /// held by the same virtual register. The equivalence class is the transitive | |||
| 153 | /// closure of that relation. | |||
| 154 | class UserValue { | |||
| 155 | const DILocalVariable *Variable; ///< The debug info variable we are part of. | |||
| 156 | const DIExpression *Expression; ///< Any complex address expression. | |||
| 157 | DebugLoc dl; ///< The debug location for the variable. This is | |||
| 158 | ///< used by dwarf writer to find lexical scope. | |||
| 159 | UserValue *leader; ///< Equivalence class leader. | |||
| 160 | UserValue *next = nullptr; ///< Next value in equivalence class, or null. | |||
| 161 | ||||
| 162 | /// Numbered locations referenced by locmap. | |||
| 163 | SmallVector<MachineOperand, 4> locations; | |||
| 164 | ||||
| 165 | /// Map of slot indices where this value is live. | |||
| 166 | LocMap locInts; | |||
| 167 | ||||
| 168 | /// Insert a DBG_VALUE into MBB at Idx for LocNo. | |||
| 169 | void insertDebugValue(MachineBasicBlock *MBB, SlotIndex StartIdx, | |||
| 170 | SlotIndex StopIdx, DbgValueLocation Loc, bool Spilled, | |||
| 171 | unsigned SpillOffset, LiveIntervals &LIS, | |||
| 172 | const TargetInstrInfo &TII, | |||
| 173 | const TargetRegisterInfo &TRI); | |||
| 174 | ||||
| 175 | /// Replace OldLocNo ranges with NewRegs ranges where NewRegs | |||
| 176 | /// is live. Returns true if any changes were made. | |||
| 177 | bool splitLocation(unsigned OldLocNo, ArrayRef<unsigned> NewRegs, | |||
| 178 | LiveIntervals &LIS); | |||
| 179 | ||||
| 180 | public: | |||
| 181 | /// Create a new UserValue. | |||
| 182 | UserValue(const DILocalVariable *var, const DIExpression *expr, DebugLoc L, | |||
| 183 | LocMap::Allocator &alloc) | |||
| 184 | : Variable(var), Expression(expr), dl(std::move(L)), leader(this), | |||
| 185 | locInts(alloc) {} | |||
| 186 | ||||
| 187 | /// Get the leader of this value's equivalence class. | |||
| 188 | UserValue *getLeader() { | |||
| 189 | UserValue *l = leader; | |||
| 190 | while (l != l->leader) | |||
| 191 | l = l->leader; | |||
| 192 | return leader = l; | |||
| 193 | } | |||
| 194 | ||||
| 195 | /// Return the next UserValue in the equivalence class. | |||
| 196 | UserValue *getNext() const { return next; } | |||
| 197 | ||||
| 198 | /// Does this UserValue match the parameters? | |||
| 199 | bool match(const DILocalVariable *Var, const DIExpression *Expr, | |||
| 200 | const DILocation *IA) const { | |||
| 201 | // FIXME: The fragment should be part of the equivalence class, but not | |||
| 202 | // other things in the expression like stack values. | |||
| 203 | return Var == Variable && Expr == Expression && dl->getInlinedAt() == IA; | |||
| 204 | } | |||
| 205 | ||||
| 206 | /// Merge equivalence classes. | |||
| 207 | static UserValue *merge(UserValue *L1, UserValue *L2) { | |||
| 208 | L2 = L2->getLeader(); | |||
| 209 | if (!L1) | |||
| 210 | return L2; | |||
| 211 | L1 = L1->getLeader(); | |||
| 212 | if (L1 == L2) | |||
| 213 | return L1; | |||
| 214 | // Splice L2 before L1's members. | |||
| 215 | UserValue *End = L2; | |||
| 216 | while (End->next) { | |||
| 217 | End->leader = L1; | |||
| 218 | End = End->next; | |||
| 219 | } | |||
| 220 | End->leader = L1; | |||
| 221 | End->next = L1->next; | |||
| 222 | L1->next = L2; | |||
| 223 | return L1; | |||
| 224 | } | |||
| 225 | ||||
| 226 | /// Return the location number that matches Loc. | |||
| 227 | /// | |||
| 228 | /// For undef values we always return location number UndefLocNo without | |||
| 229 | /// inserting anything in locations. Since locations is a vector and the | |||
| 230 | /// location number is the position in the vector and UndefLocNo is ~0, | |||
| 231 | /// we would need a very big vector to put the value at the right position. | |||
| 232 | unsigned getLocationNo(const MachineOperand &LocMO) { | |||
| 233 | if (LocMO.isReg()) { | |||
| 234 | if (LocMO.getReg() == 0) | |||
| 235 | return UndefLocNo; | |||
| 236 | // For register locations we dont care about use/def and other flags. | |||
| 237 | for (unsigned i = 0, e = locations.size(); i != e; ++i) | |||
| 238 | if (locations[i].isReg() && | |||
| 239 | locations[i].getReg() == LocMO.getReg() && | |||
| 240 | locations[i].getSubReg() == LocMO.getSubReg()) | |||
| 241 | return i; | |||
| 242 | } else | |||
| 243 | for (unsigned i = 0, e = locations.size(); i != e; ++i) | |||
| 244 | if (LocMO.isIdenticalTo(locations[i])) | |||
| 245 | return i; | |||
| 246 | locations.push_back(LocMO); | |||
| 247 | // We are storing a MachineOperand outside a MachineInstr. | |||
| 248 | locations.back().clearParent(); | |||
| 249 | // Don't store def operands. | |||
| 250 | if (locations.back().isReg()) { | |||
| 251 | if (locations.back().isDef()) | |||
| 252 | locations.back().setIsDead(false); | |||
| 253 | locations.back().setIsUse(); | |||
| 254 | } | |||
| 255 | return locations.size() - 1; | |||
| 256 | } | |||
| 257 | ||||
| 258 | /// Remove (recycle) a location number. If \p LocNo still is used by the | |||
| 259 | /// locInts nothing is done. | |||
| 260 | void removeLocationIfUnused(unsigned LocNo) { | |||
| 261 | // Bail out if LocNo still is used. | |||
| 262 | for (LocMap::const_iterator I = locInts.begin(); I.valid(); ++I) { | |||
| 263 | DbgValueLocation Loc = I.value(); | |||
| 264 | if (Loc.locNo() == LocNo) | |||
| 265 | return; | |||
| 266 | } | |||
| 267 | // Remove the entry in the locations vector, and adjust all references to | |||
| 268 | // location numbers above the removed entry. | |||
| 269 | locations.erase(locations.begin() + LocNo); | |||
| 270 | for (LocMap::iterator I = locInts.begin(); I.valid(); ++I) { | |||
| 271 | DbgValueLocation Loc = I.value(); | |||
| 272 | if (!Loc.isUndef() && Loc.locNo() > LocNo) | |||
| 273 | I.setValueUnchecked(Loc.changeLocNo(Loc.locNo() - 1)); | |||
| 274 | } | |||
| 275 | } | |||
| 276 | ||||
| 277 | /// Ensure that all virtual register locations are mapped. | |||
| 278 | void mapVirtRegs(LDVImpl *LDV); | |||
| 279 | ||||
| 280 | /// Add a definition point to this value. | |||
| 281 | void addDef(SlotIndex Idx, const MachineOperand &LocMO) { | |||
| 282 | DbgValueLocation Loc(getLocationNo(LocMO)); | |||
| 283 | // Add a singular (Idx,Idx) -> Loc mapping. | |||
| 284 | LocMap::iterator I = locInts.find(Idx); | |||
| 285 | if (!I.valid() || I.start() != Idx) | |||
| 286 | I.insert(Idx, Idx.getNextSlot(), Loc); | |||
| 287 | else | |||
| 288 | // A later DBG_VALUE at the same SlotIndex overrides the old location. | |||
| 289 | I.setValue(Loc); | |||
| 290 | } | |||
| 291 | ||||
| 292 | /// Extend the current definition as far as possible down. | |||
| 293 | /// | |||
| 294 | /// Stop when meeting an existing def or when leaving the live | |||
| 295 | /// range of VNI. End points where VNI is no longer live are added to Kills. | |||
| 296 | /// | |||
| 297 | /// We only propagate DBG_VALUES locally here. LiveDebugValues performs a | |||
| 298 | /// data-flow analysis to propagate them beyond basic block boundaries. | |||
| 299 | /// | |||
| 300 | /// \param Idx Starting point for the definition. | |||
| 301 | /// \param Loc Location number to propagate. | |||
| 302 | /// \param LR Restrict liveness to where LR has the value VNI. May be null. | |||
| 303 | /// \param VNI When LR is not null, this is the value to restrict to. | |||
| 304 | /// \param [out] Kills Append end points of VNI's live range to Kills. | |||
| 305 | /// \param LIS Live intervals analysis. | |||
| 306 | void extendDef(SlotIndex Idx, DbgValueLocation Loc, | |||
| 307 | LiveRange *LR, const VNInfo *VNI, | |||
| 308 | SmallVectorImpl<SlotIndex> *Kills, | |||
| 309 | LiveIntervals &LIS); | |||
| 310 | ||||
| 311 | /// The value in LI/LocNo may be copies to other registers. Determine if | |||
| 312 | /// any of the copies are available at the kill points, and add defs if | |||
| 313 | /// possible. | |||
| 314 | /// | |||
| 315 | /// \param LI Scan for copies of the value in LI->reg. | |||
| 316 | /// \param LocNo Location number of LI->reg. | |||
| 317 | /// \param Kills Points where the range of LocNo could be extended. | |||
| 318 | /// \param [in,out] NewDefs Append (Idx, LocNo) of inserted defs here. | |||
| 319 | void addDefsFromCopies( | |||
| 320 | LiveInterval *LI, unsigned LocNo, | |||
| 321 | const SmallVectorImpl<SlotIndex> &Kills, | |||
| 322 | SmallVectorImpl<std::pair<SlotIndex, DbgValueLocation>> &NewDefs, | |||
| 323 | MachineRegisterInfo &MRI, LiveIntervals &LIS); | |||
| 324 | ||||
| 325 | /// Compute the live intervals of all locations after collecting all their | |||
| 326 | /// def points. | |||
| 327 | void computeIntervals(MachineRegisterInfo &MRI, const TargetRegisterInfo &TRI, | |||
| 328 | LiveIntervals &LIS, LexicalScopes &LS); | |||
| 329 | ||||
| 330 | /// Replace OldReg ranges with NewRegs ranges where NewRegs is | |||
| 331 | /// live. Returns true if any changes were made. | |||
| 332 | bool splitRegister(unsigned OldReg, ArrayRef<unsigned> NewRegs, | |||
| 333 | LiveIntervals &LIS); | |||
| 334 | ||||
| 335 | /// Rewrite virtual register locations according to the provided virtual | |||
| 336 | /// register map. Record the stack slot offsets for the locations that | |||
| 337 | /// were spilled. | |||
| 338 | void rewriteLocations(VirtRegMap &VRM, const MachineFunction &MF, | |||
| 339 | const TargetInstrInfo &TII, | |||
| 340 | const TargetRegisterInfo &TRI, | |||
| 341 | SpillOffsetMap &SpillOffsets); | |||
| 342 | ||||
| 343 | /// Recreate DBG_VALUE instruction from data structures. | |||
| 344 | void emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS, | |||
| 345 | const TargetInstrInfo &TII, | |||
| 346 | const TargetRegisterInfo &TRI, | |||
| 347 | const SpillOffsetMap &SpillOffsets); | |||
| 348 | ||||
| 349 | /// Return DebugLoc of this UserValue. | |||
| 350 | DebugLoc getDebugLoc() { return dl;} | |||
| 351 | ||||
| 352 | void print(raw_ostream &, const TargetRegisterInfo *); | |||
| 353 | }; | |||
| 354 | ||||
| 355 | /// A user label is a part of a debug info user label. | |||
| 356 | class UserLabel { | |||
| 357 | const DILabel *Label; ///< The debug info label we are part of. | |||
| 358 | DebugLoc dl; ///< The debug location for the label. This is | |||
| 359 | ///< used by dwarf writer to find lexical scope. | |||
| 360 | SlotIndex loc; ///< Slot used by the debug label. | |||
| 361 | ||||
| 362 | /// Insert a DBG_LABEL into MBB at Idx. | |||
| 363 | void insertDebugLabel(MachineBasicBlock *MBB, SlotIndex Idx, | |||
| 364 | LiveIntervals &LIS, const TargetInstrInfo &TII); | |||
| 365 | ||||
| 366 | public: | |||
| 367 | /// Create a new UserLabel. | |||
| 368 | UserLabel(const DILabel *label, DebugLoc L, SlotIndex Idx) | |||
| 369 | : Label(label), dl(std::move(L)), loc(Idx) {} | |||
| 370 | ||||
| 371 | /// Does this UserLabel match the parameters? | |||
| 372 | bool match(const DILabel *L, const DILocation *IA, | |||
| 373 | const SlotIndex Index) const { | |||
| 374 | return Label == L && dl->getInlinedAt() == IA && loc == Index; | |||
| 375 | } | |||
| 376 | ||||
| 377 | /// Recreate DBG_LABEL instruction from data structures. | |||
| 378 | void emitDebugLabel(LiveIntervals &LIS, const TargetInstrInfo &TII); | |||
| 379 | ||||
| 380 | /// Return DebugLoc of this UserLabel. | |||
| 381 | DebugLoc getDebugLoc() { return dl; } | |||
| 382 | ||||
| 383 | void print(raw_ostream &, const TargetRegisterInfo *); | |||
| 384 | }; | |||
| 385 | ||||
| 386 | /// Implementation of the LiveDebugVariables pass. | |||
| 387 | class LDVImpl { | |||
| 388 | LiveDebugVariables &pass; | |||
| 389 | LocMap::Allocator allocator; | |||
| 390 | MachineFunction *MF = nullptr; | |||
| 391 | LiveIntervals *LIS; | |||
| 392 | const TargetRegisterInfo *TRI; | |||
| 393 | ||||
| 394 | /// Whether emitDebugValues is called. | |||
| 395 | bool EmitDone = false; | |||
| 396 | ||||
| 397 | /// Whether the machine function is modified during the pass. | |||
| 398 | bool ModifiedMF = false; | |||
| 399 | ||||
| 400 | /// All allocated UserValue instances. | |||
| 401 | SmallVector<std::unique_ptr<UserValue>, 8> userValues; | |||
| 402 | ||||
| 403 | /// All allocated UserLabel instances. | |||
| 404 | SmallVector<std::unique_ptr<UserLabel>, 2> userLabels; | |||
| 405 | ||||
| 406 | /// Map virtual register to eq class leader. | |||
| 407 | using VRMap = DenseMap<unsigned, UserValue *>; | |||
| 408 | VRMap virtRegToEqClass; | |||
| 409 | ||||
| 410 | /// Map user variable to eq class leader. | |||
| 411 | using UVMap = DenseMap<const DILocalVariable *, UserValue *>; | |||
| 412 | UVMap userVarMap; | |||
| 413 | ||||
| 414 | /// Find or create a UserValue. | |||
| 415 | UserValue *getUserValue(const DILocalVariable *Var, const DIExpression *Expr, | |||
| 416 | const DebugLoc &DL); | |||
| 417 | ||||
| 418 | /// Find the EC leader for VirtReg or null. | |||
| 419 | UserValue *lookupVirtReg(unsigned VirtReg); | |||
| 420 | ||||
| 421 | /// Add DBG_VALUE instruction to our maps. | |||
| 422 | /// | |||
| 423 | /// \param MI DBG_VALUE instruction | |||
| 424 | /// \param Idx Last valid SLotIndex before instruction. | |||
| 425 | /// | |||
| 426 | /// \returns True if the DBG_VALUE instruction should be deleted. | |||
| 427 | bool handleDebugValue(MachineInstr &MI, SlotIndex Idx); | |||
| 428 | ||||
| 429 | /// Add DBG_LABEL instruction to UserLabel. | |||
| 430 | /// | |||
| 431 | /// \param MI DBG_LABEL instruction | |||
| 432 | /// \param Idx Last valid SlotIndex before instruction. | |||
| 433 | /// | |||
| 434 | /// \returns True if the DBG_LABEL instruction should be deleted. | |||
| 435 | bool handleDebugLabel(MachineInstr &MI, SlotIndex Idx); | |||
| 436 | ||||
| 437 | /// Collect and erase all DBG_VALUE instructions, adding a UserValue def | |||
| 438 | /// for each instruction. | |||
| 439 | /// | |||
| 440 | /// \param mf MachineFunction to be scanned. | |||
| 441 | /// | |||
| 442 | /// \returns True if any debug values were found. | |||
| 443 | bool collectDebugValues(MachineFunction &mf); | |||
| 444 | ||||
| 445 | /// Compute the live intervals of all user values after collecting all | |||
| 446 | /// their def points. | |||
| 447 | void computeIntervals(); | |||
| 448 | ||||
| 449 | public: | |||
| 450 | LDVImpl(LiveDebugVariables *ps) : pass(*ps) {} | |||
| 451 | ||||
| 452 | bool runOnMachineFunction(MachineFunction &mf); | |||
| 453 | ||||
| 454 | /// Release all memory. | |||
| 455 | void clear() { | |||
| 456 | MF = nullptr; | |||
| 457 | userValues.clear(); | |||
| 458 | userLabels.clear(); | |||
| 459 | virtRegToEqClass.clear(); | |||
| 460 | userVarMap.clear(); | |||
| 461 | // Make sure we call emitDebugValues if the machine function was modified. | |||
| 462 | assert((!ModifiedMF || EmitDone) &&(((!ModifiedMF || EmitDone) && "Dbg values are not emitted in LDV" ) ? static_cast<void> (0) : __assert_fail ("(!ModifiedMF || EmitDone) && \"Dbg values are not emitted in LDV\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 463, __PRETTY_FUNCTION__)) | |||
| 463 | "Dbg values are not emitted in LDV")(((!ModifiedMF || EmitDone) && "Dbg values are not emitted in LDV" ) ? static_cast<void> (0) : __assert_fail ("(!ModifiedMF || EmitDone) && \"Dbg values are not emitted in LDV\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 463, __PRETTY_FUNCTION__)); | |||
| 464 | EmitDone = false; | |||
| 465 | ModifiedMF = false; | |||
| 466 | } | |||
| 467 | ||||
| 468 | /// Map virtual register to an equivalence class. | |||
| 469 | void mapVirtReg(unsigned VirtReg, UserValue *EC); | |||
| 470 | ||||
| 471 | /// Replace all references to OldReg with NewRegs. | |||
| 472 | void splitRegister(unsigned OldReg, ArrayRef<unsigned> NewRegs); | |||
| 473 | ||||
| 474 | /// Recreate DBG_VALUE instruction from data structures. | |||
| 475 | void emitDebugValues(VirtRegMap *VRM); | |||
| 476 | ||||
| 477 | void print(raw_ostream&); | |||
| 478 | }; | |||
| 479 | ||||
| 480 | } // end anonymous namespace | |||
| 481 | ||||
| 482 | #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) | |||
| 483 | static void printDebugLoc(const DebugLoc &DL, raw_ostream &CommentOS, | |||
| 484 | const LLVMContext &Ctx) { | |||
| 485 | if (!DL) | |||
| 486 | return; | |||
| 487 | ||||
| 488 | auto *Scope = cast<DIScope>(DL.getScope()); | |||
| 489 | // Omit the directory, because it's likely to be long and uninteresting. | |||
| 490 | CommentOS << Scope->getFilename(); | |||
| 491 | CommentOS << ':' << DL.getLine(); | |||
| 492 | if (DL.getCol() != 0) | |||
| 493 | CommentOS << ':' << DL.getCol(); | |||
| 494 | ||||
| 495 | DebugLoc InlinedAtDL = DL.getInlinedAt(); | |||
| 496 | if (!InlinedAtDL) | |||
| 497 | return; | |||
| 498 | ||||
| 499 | CommentOS << " @[ "; | |||
| 500 | printDebugLoc(InlinedAtDL, CommentOS, Ctx); | |||
| 501 | CommentOS << " ]"; | |||
| 502 | } | |||
| 503 | ||||
| 504 | static void printExtendedName(raw_ostream &OS, const DINode *Node, | |||
| 505 | const DILocation *DL) { | |||
| 506 | const LLVMContext &Ctx = Node->getContext(); | |||
| 507 | StringRef Res; | |||
| 508 | unsigned Line; | |||
| 509 | if (const auto *V
| |||
| 510 | Res = V->getName(); | |||
| 511 | Line = V->getLine(); | |||
| 512 | } else if (const auto *L
| |||
| 513 | Res = L->getName(); | |||
| 514 | Line = L->getLine(); | |||
| 515 | } | |||
| 516 | ||||
| 517 | if (!Res.empty()) | |||
| 518 | OS << Res << "," << Line; | |||
| ||||
| 519 | auto *InlinedAt = DL ? DL->getInlinedAt() : nullptr; | |||
| 520 | if (InlinedAt) { | |||
| 521 | if (DebugLoc InlinedAtDL = InlinedAt) { | |||
| 522 | OS << " @["; | |||
| 523 | printDebugLoc(InlinedAtDL, OS, Ctx); | |||
| 524 | OS << "]"; | |||
| 525 | } | |||
| 526 | } | |||
| 527 | } | |||
| 528 | ||||
| 529 | void UserValue::print(raw_ostream &OS, const TargetRegisterInfo *TRI) { | |||
| 530 | OS << "!\""; | |||
| 531 | printExtendedName(OS, Variable, dl); | |||
| 532 | ||||
| 533 | OS << "\"\t"; | |||
| 534 | for (LocMap::const_iterator I = locInts.begin(); I.valid(); ++I) { | |||
| 535 | OS << " [" << I.start() << ';' << I.stop() << "):"; | |||
| 536 | if (I.value().isUndef()) | |||
| 537 | OS << "undef"; | |||
| 538 | else { | |||
| 539 | OS << I.value().locNo(); | |||
| 540 | } | |||
| 541 | } | |||
| 542 | for (unsigned i = 0, e = locations.size(); i != e; ++i) { | |||
| 543 | OS << " Loc" << i << '='; | |||
| 544 | locations[i].print(OS, TRI); | |||
| 545 | } | |||
| 546 | OS << '\n'; | |||
| 547 | } | |||
| 548 | ||||
| 549 | void UserLabel::print(raw_ostream &OS, const TargetRegisterInfo *TRI) { | |||
| 550 | OS << "!\""; | |||
| 551 | printExtendedName(OS, Label, dl); | |||
| 552 | ||||
| 553 | OS << "\"\t"; | |||
| 554 | OS << loc; | |||
| 555 | OS << '\n'; | |||
| 556 | } | |||
| 557 | ||||
| 558 | void LDVImpl::print(raw_ostream &OS) { | |||
| 559 | OS << "********** DEBUG VARIABLES **********\n"; | |||
| 560 | for (auto &userValue : userValues) | |||
| 561 | userValue->print(OS, TRI); | |||
| 562 | OS << "********** DEBUG LABELS **********\n"; | |||
| 563 | for (auto &userLabel : userLabels) | |||
| 564 | userLabel->print(OS, TRI); | |||
| 565 | } | |||
| 566 | #endif | |||
| 567 | ||||
| 568 | void UserValue::mapVirtRegs(LDVImpl *LDV) { | |||
| 569 | for (unsigned i = 0, e = locations.size(); i != e; ++i) | |||
| 570 | if (locations[i].isReg() && | |||
| 571 | Register::isVirtualRegister(locations[i].getReg())) | |||
| 572 | LDV->mapVirtReg(locations[i].getReg(), this); | |||
| 573 | } | |||
| 574 | ||||
| 575 | UserValue *LDVImpl::getUserValue(const DILocalVariable *Var, | |||
| 576 | const DIExpression *Expr, const DebugLoc &DL) { | |||
| 577 | UserValue *&Leader = userVarMap[Var]; | |||
| 578 | if (Leader) { | |||
| 579 | UserValue *UV = Leader->getLeader(); | |||
| 580 | Leader = UV; | |||
| 581 | for (; UV; UV = UV->getNext()) | |||
| 582 | if (UV->match(Var, Expr, DL->getInlinedAt())) | |||
| 583 | return UV; | |||
| 584 | } | |||
| 585 | ||||
| 586 | userValues.push_back( | |||
| 587 | std::make_unique<UserValue>(Var, Expr, DL, allocator)); | |||
| 588 | UserValue *UV = userValues.back().get(); | |||
| 589 | Leader = UserValue::merge(Leader, UV); | |||
| 590 | return UV; | |||
| 591 | } | |||
| 592 | ||||
| 593 | void LDVImpl::mapVirtReg(unsigned VirtReg, UserValue *EC) { | |||
| 594 | assert(Register::isVirtualRegister(VirtReg) && "Only map VirtRegs")((Register::isVirtualRegister(VirtReg) && "Only map VirtRegs" ) ? static_cast<void> (0) : __assert_fail ("Register::isVirtualRegister(VirtReg) && \"Only map VirtRegs\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 594, __PRETTY_FUNCTION__)); | |||
| 595 | UserValue *&Leader = virtRegToEqClass[VirtReg]; | |||
| 596 | Leader = UserValue::merge(Leader, EC); | |||
| 597 | } | |||
| 598 | ||||
| 599 | UserValue *LDVImpl::lookupVirtReg(unsigned VirtReg) { | |||
| 600 | if (UserValue *UV = virtRegToEqClass.lookup(VirtReg)) | |||
| 601 | return UV->getLeader(); | |||
| 602 | return nullptr; | |||
| 603 | } | |||
| 604 | ||||
| 605 | bool LDVImpl::handleDebugValue(MachineInstr &MI, SlotIndex Idx) { | |||
| 606 | // DBG_VALUE loc, offset, variable | |||
| 607 | if (MI.getNumOperands() != 4 || | |||
| 608 | !(MI.getOperand(1).isReg() || MI.getOperand(1).isImm()) || | |||
| 609 | !MI.getOperand(2).isMetadata()) { | |||
| 610 | LLVM_DEBUG(dbgs() << "Can't handle " << MI)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "Can't handle " << MI; } } while (false); | |||
| 611 | return false; | |||
| 612 | } | |||
| 613 | ||||
| 614 | // Detect invalid DBG_VALUE instructions, with a debug-use of a virtual | |||
| 615 | // register that hasn't been defined yet. If we do not remove those here, then | |||
| 616 | // the re-insertion of the DBG_VALUE instruction after register allocation | |||
| 617 | // will be incorrect. | |||
| 618 | // TODO: If earlier passes are corrected to generate sane debug information | |||
| 619 | // (and if the machine verifier is improved to catch this), then these checks | |||
| 620 | // could be removed or replaced by asserts. | |||
| 621 | bool Discard = false; | |||
| 622 | if (MI.getOperand(0).isReg() && | |||
| 623 | Register::isVirtualRegister(MI.getOperand(0).getReg())) { | |||
| 624 | const Register Reg = MI.getOperand(0).getReg(); | |||
| 625 | if (!LIS->hasInterval(Reg)) { | |||
| 626 | // The DBG_VALUE is described by a virtual register that does not have a | |||
| 627 | // live interval. Discard the DBG_VALUE. | |||
| 628 | Discard = true; | |||
| 629 | LLVM_DEBUG(dbgs() << "Discarding debug info (no LIS interval): " << Idxdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "Discarding debug info (no LIS interval): " << Idx << " " << MI; } } while (false) | |||
| 630 | << " " << MI)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "Discarding debug info (no LIS interval): " << Idx << " " << MI; } } while (false); | |||
| 631 | } else { | |||
| 632 | // The DBG_VALUE is only valid if either Reg is live out from Idx, or Reg | |||
| 633 | // is defined dead at Idx (where Idx is the slot index for the instruction | |||
| 634 | // preceding the DBG_VALUE). | |||
| 635 | const LiveInterval &LI = LIS->getInterval(Reg); | |||
| 636 | LiveQueryResult LRQ = LI.Query(Idx); | |||
| 637 | if (!LRQ.valueOutOrDead()) { | |||
| 638 | // We have found a DBG_VALUE with the value in a virtual register that | |||
| 639 | // is not live. Discard the DBG_VALUE. | |||
| 640 | Discard = true; | |||
| 641 | LLVM_DEBUG(dbgs() << "Discarding debug info (reg not live): " << Idxdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "Discarding debug info (reg not live): " << Idx << " " << MI; } } while (false) | |||
| 642 | << " " << MI)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "Discarding debug info (reg not live): " << Idx << " " << MI; } } while (false); | |||
| 643 | } | |||
| 644 | } | |||
| 645 | } | |||
| 646 | ||||
| 647 | // Get or create the UserValue for (variable,offset) here. | |||
| 648 | assert(!MI.getOperand(1).isImm() && "DBG_VALUE with indirect flag before "((!MI.getOperand(1).isImm() && "DBG_VALUE with indirect flag before " "LiveDebugVariables") ? static_cast<void> (0) : __assert_fail ("!MI.getOperand(1).isImm() && \"DBG_VALUE with indirect flag before \" \"LiveDebugVariables\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 649, __PRETTY_FUNCTION__)) | |||
| 649 | "LiveDebugVariables")((!MI.getOperand(1).isImm() && "DBG_VALUE with indirect flag before " "LiveDebugVariables") ? static_cast<void> (0) : __assert_fail ("!MI.getOperand(1).isImm() && \"DBG_VALUE with indirect flag before \" \"LiveDebugVariables\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 649, __PRETTY_FUNCTION__)); | |||
| 650 | const DILocalVariable *Var = MI.getDebugVariable(); | |||
| 651 | const DIExpression *Expr = MI.getDebugExpression(); | |||
| 652 | UserValue *UV = | |||
| 653 | getUserValue(Var, Expr, MI.getDebugLoc()); | |||
| 654 | if (!Discard) | |||
| 655 | UV->addDef(Idx, MI.getOperand(0)); | |||
| 656 | else { | |||
| 657 | MachineOperand MO = MachineOperand::CreateReg(0U, false); | |||
| 658 | MO.setIsDebug(); | |||
| 659 | UV->addDef(Idx, MO); | |||
| 660 | } | |||
| 661 | return true; | |||
| 662 | } | |||
| 663 | ||||
| 664 | bool LDVImpl::handleDebugLabel(MachineInstr &MI, SlotIndex Idx) { | |||
| 665 | // DBG_LABEL label | |||
| 666 | if (MI.getNumOperands() != 1 || !MI.getOperand(0).isMetadata()) { | |||
| 667 | LLVM_DEBUG(dbgs() << "Can't handle " << MI)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "Can't handle " << MI; } } while (false); | |||
| 668 | return false; | |||
| 669 | } | |||
| 670 | ||||
| 671 | // Get or create the UserLabel for label here. | |||
| 672 | const DILabel *Label = MI.getDebugLabel(); | |||
| 673 | const DebugLoc &DL = MI.getDebugLoc(); | |||
| 674 | bool Found = false; | |||
| 675 | for (auto const &L : userLabels) { | |||
| 676 | if (L->match(Label, DL->getInlinedAt(), Idx)) { | |||
| 677 | Found = true; | |||
| 678 | break; | |||
| 679 | } | |||
| 680 | } | |||
| 681 | if (!Found) | |||
| 682 | userLabels.push_back(std::make_unique<UserLabel>(Label, DL, Idx)); | |||
| 683 | ||||
| 684 | return true; | |||
| 685 | } | |||
| 686 | ||||
| 687 | bool LDVImpl::collectDebugValues(MachineFunction &mf) { | |||
| 688 | bool Changed = false; | |||
| 689 | for (MachineFunction::iterator MFI = mf.begin(), MFE = mf.end(); MFI != MFE; | |||
| 690 | ++MFI) { | |||
| 691 | MachineBasicBlock *MBB = &*MFI; | |||
| 692 | for (MachineBasicBlock::iterator MBBI = MBB->begin(), MBBE = MBB->end(); | |||
| 693 | MBBI != MBBE;) { | |||
| 694 | // Use the first debug instruction in the sequence to get a SlotIndex | |||
| 695 | // for following consecutive debug instructions. | |||
| 696 | if (!MBBI->isDebugInstr()) { | |||
| 697 | ++MBBI; | |||
| 698 | continue; | |||
| 699 | } | |||
| 700 | // Debug instructions has no slot index. Use the previous | |||
| 701 | // non-debug instruction's SlotIndex as its SlotIndex. | |||
| 702 | SlotIndex Idx = | |||
| 703 | MBBI == MBB->begin() | |||
| 704 | ? LIS->getMBBStartIdx(MBB) | |||
| 705 | : LIS->getInstructionIndex(*std::prev(MBBI)).getRegSlot(); | |||
| 706 | // Handle consecutive debug instructions with the same slot index. | |||
| 707 | do { | |||
| 708 | // Only handle DBG_VALUE in handleDebugValue(). Skip all other | |||
| 709 | // kinds of debug instructions. | |||
| 710 | if ((MBBI->isDebugValue() && handleDebugValue(*MBBI, Idx)) || | |||
| 711 | (MBBI->isDebugLabel() && handleDebugLabel(*MBBI, Idx))) { | |||
| 712 | MBBI = MBB->erase(MBBI); | |||
| 713 | Changed = true; | |||
| 714 | } else | |||
| 715 | ++MBBI; | |||
| 716 | } while (MBBI != MBBE && MBBI->isDebugInstr()); | |||
| 717 | } | |||
| 718 | } | |||
| 719 | return Changed; | |||
| 720 | } | |||
| 721 | ||||
| 722 | void UserValue::extendDef(SlotIndex Idx, DbgValueLocation Loc, LiveRange *LR, | |||
| 723 | const VNInfo *VNI, SmallVectorImpl<SlotIndex> *Kills, | |||
| 724 | LiveIntervals &LIS) { | |||
| 725 | SlotIndex Start = Idx; | |||
| 726 | MachineBasicBlock *MBB = LIS.getMBBFromIndex(Start); | |||
| 727 | SlotIndex Stop = LIS.getMBBEndIdx(MBB); | |||
| 728 | LocMap::iterator I = locInts.find(Start); | |||
| 729 | ||||
| 730 | // Limit to VNI's live range. | |||
| 731 | bool ToEnd = true; | |||
| 732 | if (LR && VNI) { | |||
| 733 | LiveInterval::Segment *Segment = LR->getSegmentContaining(Start); | |||
| 734 | if (!Segment || Segment->valno != VNI) { | |||
| 735 | if (Kills) | |||
| 736 | Kills->push_back(Start); | |||
| 737 | return; | |||
| 738 | } | |||
| 739 | if (Segment->end < Stop) { | |||
| 740 | Stop = Segment->end; | |||
| 741 | ToEnd = false; | |||
| 742 | } | |||
| 743 | } | |||
| 744 | ||||
| 745 | // There could already be a short def at Start. | |||
| 746 | if (I.valid() && I.start() <= Start) { | |||
| 747 | // Stop when meeting a different location or an already extended interval. | |||
| 748 | Start = Start.getNextSlot(); | |||
| 749 | if (I.value() != Loc || I.stop() != Start) | |||
| 750 | return; | |||
| 751 | // This is a one-slot placeholder. Just skip it. | |||
| 752 | ++I; | |||
| 753 | } | |||
| 754 | ||||
| 755 | // Limited by the next def. | |||
| 756 | if (I.valid() && I.start() < Stop) | |||
| 757 | Stop = I.start(); | |||
| 758 | // Limited by VNI's live range. | |||
| 759 | else if (!ToEnd && Kills) | |||
| 760 | Kills->push_back(Stop); | |||
| 761 | ||||
| 762 | if (Start < Stop) | |||
| 763 | I.insert(Start, Stop, Loc); | |||
| 764 | } | |||
| 765 | ||||
| 766 | void UserValue::addDefsFromCopies( | |||
| 767 | LiveInterval *LI, unsigned LocNo, | |||
| 768 | const SmallVectorImpl<SlotIndex> &Kills, | |||
| 769 | SmallVectorImpl<std::pair<SlotIndex, DbgValueLocation>> &NewDefs, | |||
| 770 | MachineRegisterInfo &MRI, LiveIntervals &LIS) { | |||
| 771 | if (Kills.empty()) | |||
| 772 | return; | |||
| 773 | // Don't track copies from physregs, there are too many uses. | |||
| 774 | if (!Register::isVirtualRegister(LI->reg)) | |||
| 775 | return; | |||
| 776 | ||||
| 777 | // Collect all the (vreg, valno) pairs that are copies of LI. | |||
| 778 | SmallVector<std::pair<LiveInterval*, const VNInfo*>, 8> CopyValues; | |||
| 779 | for (MachineOperand &MO : MRI.use_nodbg_operands(LI->reg)) { | |||
| 780 | MachineInstr *MI = MO.getParent(); | |||
| 781 | // Copies of the full value. | |||
| 782 | if (MO.getSubReg() || !MI->isCopy()) | |||
| 783 | continue; | |||
| 784 | Register DstReg = MI->getOperand(0).getReg(); | |||
| 785 | ||||
| 786 | // Don't follow copies to physregs. These are usually setting up call | |||
| 787 | // arguments, and the argument registers are always call clobbered. We are | |||
| 788 | // better off in the source register which could be a callee-saved register, | |||
| 789 | // or it could be spilled. | |||
| 790 | if (!Register::isVirtualRegister(DstReg)) | |||
| 791 | continue; | |||
| 792 | ||||
| 793 | // Is LocNo extended to reach this copy? If not, another def may be blocking | |||
| 794 | // it, or we are looking at a wrong value of LI. | |||
| 795 | SlotIndex Idx = LIS.getInstructionIndex(*MI); | |||
| 796 | LocMap::iterator I = locInts.find(Idx.getRegSlot(true)); | |||
| 797 | if (!I.valid() || I.value().locNo() != LocNo) | |||
| 798 | continue; | |||
| 799 | ||||
| 800 | if (!LIS.hasInterval(DstReg)) | |||
| 801 | continue; | |||
| 802 | LiveInterval *DstLI = &LIS.getInterval(DstReg); | |||
| 803 | const VNInfo *DstVNI = DstLI->getVNInfoAt(Idx.getRegSlot()); | |||
| 804 | assert(DstVNI && DstVNI->def == Idx.getRegSlot() && "Bad copy value")((DstVNI && DstVNI->def == Idx.getRegSlot() && "Bad copy value") ? static_cast<void> (0) : __assert_fail ("DstVNI && DstVNI->def == Idx.getRegSlot() && \"Bad copy value\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 804, __PRETTY_FUNCTION__)); | |||
| 805 | CopyValues.push_back(std::make_pair(DstLI, DstVNI)); | |||
| 806 | } | |||
| 807 | ||||
| 808 | if (CopyValues.empty()) | |||
| 809 | return; | |||
| 810 | ||||
| 811 | LLVM_DEBUG(dbgs() << "Got " << CopyValues.size() << " copies of " << *LIdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "Got " << CopyValues .size() << " copies of " << *LI << '\n'; } } while (false) | |||
| 812 | << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "Got " << CopyValues .size() << " copies of " << *LI << '\n'; } } while (false); | |||
| 813 | ||||
| 814 | // Try to add defs of the copied values for each kill point. | |||
| 815 | for (unsigned i = 0, e = Kills.size(); i != e; ++i) { | |||
| 816 | SlotIndex Idx = Kills[i]; | |||
| 817 | for (unsigned j = 0, e = CopyValues.size(); j != e; ++j) { | |||
| 818 | LiveInterval *DstLI = CopyValues[j].first; | |||
| 819 | const VNInfo *DstVNI = CopyValues[j].second; | |||
| 820 | if (DstLI->getVNInfoAt(Idx) != DstVNI) | |||
| 821 | continue; | |||
| 822 | // Check that there isn't already a def at Idx | |||
| 823 | LocMap::iterator I = locInts.find(Idx); | |||
| 824 | if (I.valid() && I.start() <= Idx) | |||
| 825 | continue; | |||
| 826 | LLVM_DEBUG(dbgs() << "Kill at " << Idx << " covered by valno #"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "Kill at " << Idx << " covered by valno #" << DstVNI->id << " in " << *DstLI << '\n'; } } while (false) | |||
| 827 | << DstVNI->id << " in " << *DstLI << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "Kill at " << Idx << " covered by valno #" << DstVNI->id << " in " << *DstLI << '\n'; } } while (false); | |||
| 828 | MachineInstr *CopyMI = LIS.getInstructionFromIndex(DstVNI->def); | |||
| 829 | assert(CopyMI && CopyMI->isCopy() && "Bad copy value")((CopyMI && CopyMI->isCopy() && "Bad copy value" ) ? static_cast<void> (0) : __assert_fail ("CopyMI && CopyMI->isCopy() && \"Bad copy value\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 829, __PRETTY_FUNCTION__)); | |||
| 830 | unsigned LocNo = getLocationNo(CopyMI->getOperand(0)); | |||
| 831 | DbgValueLocation NewLoc(LocNo); | |||
| 832 | I.insert(Idx, Idx.getNextSlot(), NewLoc); | |||
| 833 | NewDefs.push_back(std::make_pair(Idx, NewLoc)); | |||
| 834 | break; | |||
| 835 | } | |||
| 836 | } | |||
| 837 | } | |||
| 838 | ||||
| 839 | void UserValue::computeIntervals(MachineRegisterInfo &MRI, | |||
| 840 | const TargetRegisterInfo &TRI, | |||
| 841 | LiveIntervals &LIS, LexicalScopes &LS) { | |||
| 842 | SmallVector<std::pair<SlotIndex, DbgValueLocation>, 16> Defs; | |||
| 843 | ||||
| 844 | // Collect all defs to be extended (Skipping undefs). | |||
| 845 | for (LocMap::const_iterator I = locInts.begin(); I.valid(); ++I) | |||
| 846 | if (!I.value().isUndef()) | |||
| 847 | Defs.push_back(std::make_pair(I.start(), I.value())); | |||
| 848 | ||||
| 849 | // Extend all defs, and possibly add new ones along the way. | |||
| 850 | for (unsigned i = 0; i != Defs.size(); ++i) { | |||
| 851 | SlotIndex Idx = Defs[i].first; | |||
| 852 | DbgValueLocation Loc = Defs[i].second; | |||
| 853 | const MachineOperand &LocMO = locations[Loc.locNo()]; | |||
| 854 | ||||
| 855 | if (!LocMO.isReg()) { | |||
| 856 | extendDef(Idx, Loc, nullptr, nullptr, nullptr, LIS); | |||
| 857 | continue; | |||
| 858 | } | |||
| 859 | ||||
| 860 | // Register locations are constrained to where the register value is live. | |||
| 861 | if (Register::isVirtualRegister(LocMO.getReg())) { | |||
| 862 | LiveInterval *LI = nullptr; | |||
| 863 | const VNInfo *VNI = nullptr; | |||
| 864 | if (LIS.hasInterval(LocMO.getReg())) { | |||
| 865 | LI = &LIS.getInterval(LocMO.getReg()); | |||
| 866 | VNI = LI->getVNInfoAt(Idx); | |||
| 867 | } | |||
| 868 | SmallVector<SlotIndex, 16> Kills; | |||
| 869 | extendDef(Idx, Loc, LI, VNI, &Kills, LIS); | |||
| 870 | // FIXME: Handle sub-registers in addDefsFromCopies. The problem is that | |||
| 871 | // if the original location for example is %vreg0:sub_hi, and we find a | |||
| 872 | // full register copy in addDefsFromCopies (at the moment it only handles | |||
| 873 | // full register copies), then we must add the sub1 sub-register index to | |||
| 874 | // the new location. However, that is only possible if the new virtual | |||
| 875 | // register is of the same regclass (or if there is an equivalent | |||
| 876 | // sub-register in that regclass). For now, simply skip handling copies if | |||
| 877 | // a sub-register is involved. | |||
| 878 | if (LI && !LocMO.getSubReg()) | |||
| 879 | addDefsFromCopies(LI, Loc.locNo(), Kills, Defs, MRI, LIS); | |||
| 880 | continue; | |||
| 881 | } | |||
| 882 | ||||
| 883 | // For physregs, we only mark the start slot idx. DwarfDebug will see it | |||
| 884 | // as if the DBG_VALUE is valid up until the end of the basic block, or | |||
| 885 | // the next def of the physical register. So we do not need to extend the | |||
| 886 | // range. It might actually happen that the DBG_VALUE is the last use of | |||
| 887 | // the physical register (e.g. if this is an unused input argument to a | |||
| 888 | // function). | |||
| 889 | } | |||
| 890 | ||||
| 891 | // The computed intervals may extend beyond the range of the debug | |||
| 892 | // location's lexical scope. In this case, splitting of an interval | |||
| 893 | // can result in an interval outside of the scope being created, | |||
| 894 | // causing extra unnecessary DBG_VALUEs to be emitted. To prevent | |||
| 895 | // this, trim the intervals to the lexical scope. | |||
| 896 | ||||
| 897 | LexicalScope *Scope = LS.findLexicalScope(dl); | |||
| 898 | if (!Scope) | |||
| 899 | return; | |||
| 900 | ||||
| 901 | SlotIndex PrevEnd; | |||
| 902 | LocMap::iterator I = locInts.begin(); | |||
| 903 | ||||
| 904 | // Iterate over the lexical scope ranges. Each time round the loop | |||
| 905 | // we check the intervals for overlap with the end of the previous | |||
| 906 | // range and the start of the next. The first range is handled as | |||
| 907 | // a special case where there is no PrevEnd. | |||
| 908 | for (const InsnRange &Range : Scope->getRanges()) { | |||
| 909 | SlotIndex RStart = LIS.getInstructionIndex(*Range.first); | |||
| 910 | SlotIndex REnd = LIS.getInstructionIndex(*Range.second); | |||
| 911 | ||||
| 912 | // At the start of each iteration I has been advanced so that | |||
| 913 | // I.stop() >= PrevEnd. Check for overlap. | |||
| 914 | if (PrevEnd && I.start() < PrevEnd) { | |||
| 915 | SlotIndex IStop = I.stop(); | |||
| 916 | DbgValueLocation Loc = I.value(); | |||
| 917 | ||||
| 918 | // Stop overlaps previous end - trim the end of the interval to | |||
| 919 | // the scope range. | |||
| 920 | I.setStopUnchecked(PrevEnd); | |||
| 921 | ++I; | |||
| 922 | ||||
| 923 | // If the interval also overlaps the start of the "next" (i.e. | |||
| 924 | // current) range create a new interval for the remainder | |||
| 925 | if (RStart < IStop) | |||
| 926 | I.insert(RStart, IStop, Loc); | |||
| 927 | } | |||
| 928 | ||||
| 929 | // Advance I so that I.stop() >= RStart, and check for overlap. | |||
| 930 | I.advanceTo(RStart); | |||
| 931 | if (!I.valid()) | |||
| 932 | return; | |||
| 933 | ||||
| 934 | // The end of a lexical scope range is the last instruction in the | |||
| 935 | // range. To convert to an interval we need the index of the | |||
| 936 | // instruction after it. | |||
| 937 | REnd = REnd.getNextIndex(); | |||
| 938 | ||||
| 939 | // Advance I to first interval outside current range. | |||
| 940 | I.advanceTo(REnd); | |||
| 941 | if (!I.valid()) | |||
| 942 | return; | |||
| 943 | ||||
| 944 | PrevEnd = REnd; | |||
| 945 | } | |||
| 946 | ||||
| 947 | // Check for overlap with end of final range. | |||
| 948 | if (PrevEnd && I.start() < PrevEnd) | |||
| 949 | I.setStopUnchecked(PrevEnd); | |||
| 950 | } | |||
| 951 | ||||
| 952 | void LDVImpl::computeIntervals() { | |||
| 953 | LexicalScopes LS; | |||
| 954 | LS.initialize(*MF); | |||
| 955 | ||||
| 956 | for (unsigned i = 0, e = userValues.size(); i != e; ++i) { | |||
| 957 | userValues[i]->computeIntervals(MF->getRegInfo(), *TRI, *LIS, LS); | |||
| 958 | userValues[i]->mapVirtRegs(this); | |||
| 959 | } | |||
| 960 | } | |||
| 961 | ||||
| 962 | bool LDVImpl::runOnMachineFunction(MachineFunction &mf) { | |||
| 963 | clear(); | |||
| 964 | MF = &mf; | |||
| 965 | LIS = &pass.getAnalysis<LiveIntervals>(); | |||
| 966 | TRI = mf.getSubtarget().getRegisterInfo(); | |||
| 967 | LLVM_DEBUG(dbgs() << "********** COMPUTING LIVE DEBUG VARIABLES: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "********** COMPUTING LIVE DEBUG VARIABLES: " << mf.getName() << " **********\n"; } } while (false ) | |||
| 968 | << mf.getName() << " **********\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "********** COMPUTING LIVE DEBUG VARIABLES: " << mf.getName() << " **********\n"; } } while (false ); | |||
| 969 | ||||
| 970 | bool Changed = collectDebugValues(mf); | |||
| 971 | computeIntervals(); | |||
| 972 | LLVM_DEBUG(print(dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { print(dbgs()); } } while (false); | |||
| 973 | ModifiedMF = Changed; | |||
| 974 | return Changed; | |||
| 975 | } | |||
| 976 | ||||
| 977 | static void removeDebugValues(MachineFunction &mf) { | |||
| 978 | for (MachineBasicBlock &MBB : mf) { | |||
| 979 | for (auto MBBI = MBB.begin(), MBBE = MBB.end(); MBBI != MBBE; ) { | |||
| 980 | if (!MBBI->isDebugValue()) { | |||
| 981 | ++MBBI; | |||
| 982 | continue; | |||
| 983 | } | |||
| 984 | MBBI = MBB.erase(MBBI); | |||
| 985 | } | |||
| 986 | } | |||
| 987 | } | |||
| 988 | ||||
| 989 | bool LiveDebugVariables::runOnMachineFunction(MachineFunction &mf) { | |||
| 990 | if (!EnableLDV) | |||
| 991 | return false; | |||
| 992 | if (!mf.getFunction().getSubprogram()) { | |||
| 993 | removeDebugValues(mf); | |||
| 994 | return false; | |||
| 995 | } | |||
| 996 | if (!pImpl) | |||
| 997 | pImpl = new LDVImpl(this); | |||
| 998 | return static_cast<LDVImpl*>(pImpl)->runOnMachineFunction(mf); | |||
| 999 | } | |||
| 1000 | ||||
| 1001 | void LiveDebugVariables::releaseMemory() { | |||
| 1002 | if (pImpl) | |||
| 1003 | static_cast<LDVImpl*>(pImpl)->clear(); | |||
| 1004 | } | |||
| 1005 | ||||
| 1006 | LiveDebugVariables::~LiveDebugVariables() { | |||
| 1007 | if (pImpl) | |||
| 1008 | delete static_cast<LDVImpl*>(pImpl); | |||
| 1009 | } | |||
| 1010 | ||||
| 1011 | //===----------------------------------------------------------------------===// | |||
| 1012 | // Live Range Splitting | |||
| 1013 | //===----------------------------------------------------------------------===// | |||
| 1014 | ||||
| 1015 | bool | |||
| 1016 | UserValue::splitLocation(unsigned OldLocNo, ArrayRef<unsigned> NewRegs, | |||
| 1017 | LiveIntervals& LIS) { | |||
| 1018 | LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { { dbgs() << "Splitting Loc" << OldLocNo << '\t'; print(dbgs(), nullptr); }; } } while (false) | |||
| 1019 | dbgs() << "Splitting Loc" << OldLocNo << '\t';do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { { dbgs() << "Splitting Loc" << OldLocNo << '\t'; print(dbgs(), nullptr); }; } } while (false) | |||
| 1020 | print(dbgs(), nullptr);do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { { dbgs() << "Splitting Loc" << OldLocNo << '\t'; print(dbgs(), nullptr); }; } } while (false) | |||
| 1021 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { { dbgs() << "Splitting Loc" << OldLocNo << '\t'; print(dbgs(), nullptr); }; } } while (false); | |||
| 1022 | bool DidChange = false; | |||
| 1023 | LocMap::iterator LocMapI; | |||
| 1024 | LocMapI.setMap(locInts); | |||
| 1025 | for (unsigned i = 0; i != NewRegs.size(); ++i) { | |||
| 1026 | LiveInterval *LI = &LIS.getInterval(NewRegs[i]); | |||
| 1027 | if (LI->empty()) | |||
| 1028 | continue; | |||
| 1029 | ||||
| 1030 | // Don't allocate the new LocNo until it is needed. | |||
| 1031 | unsigned NewLocNo = UndefLocNo; | |||
| 1032 | ||||
| 1033 | // Iterate over the overlaps between locInts and LI. | |||
| 1034 | LocMapI.find(LI->beginIndex()); | |||
| 1035 | if (!LocMapI.valid()) | |||
| 1036 | continue; | |||
| 1037 | LiveInterval::iterator LII = LI->advanceTo(LI->begin(), LocMapI.start()); | |||
| 1038 | LiveInterval::iterator LIE = LI->end(); | |||
| 1039 | while (LocMapI.valid() && LII != LIE) { | |||
| 1040 | // At this point, we know that LocMapI.stop() > LII->start. | |||
| 1041 | LII = LI->advanceTo(LII, LocMapI.start()); | |||
| 1042 | if (LII == LIE) | |||
| 1043 | break; | |||
| 1044 | ||||
| 1045 | // Now LII->end > LocMapI.start(). Do we have an overlap? | |||
| 1046 | if (LocMapI.value().locNo() == OldLocNo && LII->start < LocMapI.stop()) { | |||
| 1047 | // Overlapping correct location. Allocate NewLocNo now. | |||
| 1048 | if (NewLocNo == UndefLocNo) { | |||
| 1049 | MachineOperand MO = MachineOperand::CreateReg(LI->reg, false); | |||
| 1050 | MO.setSubReg(locations[OldLocNo].getSubReg()); | |||
| 1051 | NewLocNo = getLocationNo(MO); | |||
| 1052 | DidChange = true; | |||
| 1053 | } | |||
| 1054 | ||||
| 1055 | SlotIndex LStart = LocMapI.start(); | |||
| 1056 | SlotIndex LStop = LocMapI.stop(); | |||
| 1057 | DbgValueLocation OldLoc = LocMapI.value(); | |||
| 1058 | ||||
| 1059 | // Trim LocMapI down to the LII overlap. | |||
| 1060 | if (LStart < LII->start) | |||
| 1061 | LocMapI.setStartUnchecked(LII->start); | |||
| 1062 | if (LStop > LII->end) | |||
| 1063 | LocMapI.setStopUnchecked(LII->end); | |||
| 1064 | ||||
| 1065 | // Change the value in the overlap. This may trigger coalescing. | |||
| 1066 | LocMapI.setValue(OldLoc.changeLocNo(NewLocNo)); | |||
| 1067 | ||||
| 1068 | // Re-insert any removed OldLocNo ranges. | |||
| 1069 | if (LStart < LocMapI.start()) { | |||
| 1070 | LocMapI.insert(LStart, LocMapI.start(), OldLoc); | |||
| 1071 | ++LocMapI; | |||
| 1072 | assert(LocMapI.valid() && "Unexpected coalescing")((LocMapI.valid() && "Unexpected coalescing") ? static_cast <void> (0) : __assert_fail ("LocMapI.valid() && \"Unexpected coalescing\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 1072, __PRETTY_FUNCTION__)); | |||
| 1073 | } | |||
| 1074 | if (LStop > LocMapI.stop()) { | |||
| 1075 | ++LocMapI; | |||
| 1076 | LocMapI.insert(LII->end, LStop, OldLoc); | |||
| 1077 | --LocMapI; | |||
| 1078 | } | |||
| 1079 | } | |||
| 1080 | ||||
| 1081 | // Advance to the next overlap. | |||
| 1082 | if (LII->end < LocMapI.stop()) { | |||
| 1083 | if (++LII == LIE) | |||
| 1084 | break; | |||
| 1085 | LocMapI.advanceTo(LII->start); | |||
| 1086 | } else { | |||
| 1087 | ++LocMapI; | |||
| 1088 | if (!LocMapI.valid()) | |||
| 1089 | break; | |||
| 1090 | LII = LI->advanceTo(LII, LocMapI.start()); | |||
| 1091 | } | |||
| 1092 | } | |||
| 1093 | } | |||
| 1094 | ||||
| 1095 | // Finally, remove OldLocNo unless it is still used by some interval in the | |||
| 1096 | // locInts map. One case when OldLocNo still is in use is when the register | |||
| 1097 | // has been spilled. In such situations the spilled register is kept as a | |||
| 1098 | // location until rewriteLocations is called (VirtRegMap is mapping the old | |||
| 1099 | // register to the spill slot). So for a while we can have locations that map | |||
| 1100 | // to virtual registers that have been removed from both the MachineFunction | |||
| 1101 | // and from LiveIntervals. | |||
| 1102 | removeLocationIfUnused(OldLocNo); | |||
| 1103 | ||||
| 1104 | LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { { dbgs() << "Split result: \t"; print (dbgs(), nullptr); }; } } while (false) | |||
| 1105 | dbgs() << "Split result: \t";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { { dbgs() << "Split result: \t"; print (dbgs(), nullptr); }; } } while (false) | |||
| 1106 | print(dbgs(), nullptr);do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { { dbgs() << "Split result: \t"; print (dbgs(), nullptr); }; } } while (false) | |||
| 1107 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { { dbgs() << "Split result: \t"; print (dbgs(), nullptr); }; } } while (false); | |||
| 1108 | return DidChange; | |||
| 1109 | } | |||
| 1110 | ||||
| 1111 | bool | |||
| 1112 | UserValue::splitRegister(unsigned OldReg, ArrayRef<unsigned> NewRegs, | |||
| 1113 | LiveIntervals &LIS) { | |||
| 1114 | bool DidChange = false; | |||
| 1115 | // Split locations referring to OldReg. Iterate backwards so splitLocation can | |||
| 1116 | // safely erase unused locations. | |||
| 1117 | for (unsigned i = locations.size(); i ; --i) { | |||
| 1118 | unsigned LocNo = i-1; | |||
| 1119 | const MachineOperand *Loc = &locations[LocNo]; | |||
| 1120 | if (!Loc->isReg() || Loc->getReg() != OldReg) | |||
| 1121 | continue; | |||
| 1122 | DidChange |= splitLocation(LocNo, NewRegs, LIS); | |||
| 1123 | } | |||
| 1124 | return DidChange; | |||
| 1125 | } | |||
| 1126 | ||||
| 1127 | void LDVImpl::splitRegister(unsigned OldReg, ArrayRef<unsigned> NewRegs) { | |||
| 1128 | bool DidChange = false; | |||
| 1129 | for (UserValue *UV = lookupVirtReg(OldReg); UV; UV = UV->getNext()) | |||
| 1130 | DidChange |= UV->splitRegister(OldReg, NewRegs, *LIS); | |||
| 1131 | ||||
| 1132 | if (!DidChange) | |||
| 1133 | return; | |||
| 1134 | ||||
| 1135 | // Map all of the new virtual registers. | |||
| 1136 | UserValue *UV = lookupVirtReg(OldReg); | |||
| 1137 | for (unsigned i = 0; i != NewRegs.size(); ++i) | |||
| 1138 | mapVirtReg(NewRegs[i], UV); | |||
| 1139 | } | |||
| 1140 | ||||
| 1141 | void LiveDebugVariables:: | |||
| 1142 | splitRegister(unsigned OldReg, ArrayRef<unsigned> NewRegs, LiveIntervals &LIS) { | |||
| 1143 | if (pImpl) | |||
| 1144 | static_cast<LDVImpl*>(pImpl)->splitRegister(OldReg, NewRegs); | |||
| 1145 | } | |||
| 1146 | ||||
| 1147 | void UserValue::rewriteLocations(VirtRegMap &VRM, const MachineFunction &MF, | |||
| 1148 | const TargetInstrInfo &TII, | |||
| 1149 | const TargetRegisterInfo &TRI, | |||
| 1150 | SpillOffsetMap &SpillOffsets) { | |||
| 1151 | // Build a set of new locations with new numbers so we can coalesce our | |||
| 1152 | // IntervalMap if two vreg intervals collapse to the same physical location. | |||
| 1153 | // Use MapVector instead of SetVector because MapVector::insert returns the | |||
| 1154 | // position of the previously or newly inserted element. The boolean value | |||
| 1155 | // tracks if the location was produced by a spill. | |||
| 1156 | // FIXME: This will be problematic if we ever support direct and indirect | |||
| 1157 | // frame index locations, i.e. expressing both variables in memory and | |||
| 1158 | // 'int x, *px = &x'. The "spilled" bit must become part of the location. | |||
| 1159 | MapVector<MachineOperand, std::pair<bool, unsigned>> NewLocations; | |||
| 1160 | SmallVector<unsigned, 4> LocNoMap(locations.size()); | |||
| 1161 | for (unsigned I = 0, E = locations.size(); I != E; ++I) { | |||
| 1162 | bool Spilled = false; | |||
| 1163 | unsigned SpillOffset = 0; | |||
| 1164 | MachineOperand Loc = locations[I]; | |||
| 1165 | // Only virtual registers are rewritten. | |||
| 1166 | if (Loc.isReg() && Loc.getReg() && | |||
| 1167 | Register::isVirtualRegister(Loc.getReg())) { | |||
| 1168 | Register VirtReg = Loc.getReg(); | |||
| 1169 | if (VRM.isAssignedReg(VirtReg) && | |||
| 1170 | Register::isPhysicalRegister(VRM.getPhys(VirtReg))) { | |||
| 1171 | // This can create a %noreg operand in rare cases when the sub-register | |||
| 1172 | // index is no longer available. That means the user value is in a | |||
| 1173 | // non-existent sub-register, and %noreg is exactly what we want. | |||
| 1174 | Loc.substPhysReg(VRM.getPhys(VirtReg), TRI); | |||
| 1175 | } else if (VRM.getStackSlot(VirtReg) != VirtRegMap::NO_STACK_SLOT) { | |||
| 1176 | // Retrieve the stack slot offset. | |||
| 1177 | unsigned SpillSize; | |||
| 1178 | const MachineRegisterInfo &MRI = MF.getRegInfo(); | |||
| 1179 | const TargetRegisterClass *TRC = MRI.getRegClass(VirtReg); | |||
| 1180 | bool Success = TII.getStackSlotRange(TRC, Loc.getSubReg(), SpillSize, | |||
| 1181 | SpillOffset, MF); | |||
| 1182 | ||||
| 1183 | // FIXME: Invalidate the location if the offset couldn't be calculated. | |||
| 1184 | (void)Success; | |||
| 1185 | ||||
| 1186 | Loc = MachineOperand::CreateFI(VRM.getStackSlot(VirtReg)); | |||
| 1187 | Spilled = true; | |||
| 1188 | } else { | |||
| 1189 | Loc.setReg(0); | |||
| 1190 | Loc.setSubReg(0); | |||
| 1191 | } | |||
| 1192 | } | |||
| 1193 | ||||
| 1194 | // Insert this location if it doesn't already exist and record a mapping | |||
| 1195 | // from the old number to the new number. | |||
| 1196 | auto InsertResult = NewLocations.insert({Loc, {Spilled, SpillOffset}}); | |||
| 1197 | unsigned NewLocNo = std::distance(NewLocations.begin(), InsertResult.first); | |||
| 1198 | LocNoMap[I] = NewLocNo; | |||
| 1199 | } | |||
| 1200 | ||||
| 1201 | // Rewrite the locations and record the stack slot offsets for spills. | |||
| 1202 | locations.clear(); | |||
| 1203 | SpillOffsets.clear(); | |||
| 1204 | for (auto &Pair : NewLocations) { | |||
| 1205 | bool Spilled; | |||
| 1206 | unsigned SpillOffset; | |||
| 1207 | std::tie(Spilled, SpillOffset) = Pair.second; | |||
| 1208 | locations.push_back(Pair.first); | |||
| 1209 | if (Spilled) { | |||
| 1210 | unsigned NewLocNo = std::distance(&*NewLocations.begin(), &Pair); | |||
| 1211 | SpillOffsets[NewLocNo] = SpillOffset; | |||
| 1212 | } | |||
| 1213 | } | |||
| 1214 | ||||
| 1215 | // Update the interval map, but only coalesce left, since intervals to the | |||
| 1216 | // right use the old location numbers. This should merge two contiguous | |||
| 1217 | // DBG_VALUE intervals with different vregs that were allocated to the same | |||
| 1218 | // physical register. | |||
| 1219 | for (LocMap::iterator I = locInts.begin(); I.valid(); ++I) { | |||
| 1220 | DbgValueLocation Loc = I.value(); | |||
| 1221 | // Undef values don't exist in locations (and thus not in LocNoMap either) | |||
| 1222 | // so skip over them. See getLocationNo(). | |||
| 1223 | if (Loc.isUndef()) | |||
| 1224 | continue; | |||
| 1225 | unsigned NewLocNo = LocNoMap[Loc.locNo()]; | |||
| 1226 | I.setValueUnchecked(Loc.changeLocNo(NewLocNo)); | |||
| 1227 | I.setStart(I.start()); | |||
| 1228 | } | |||
| 1229 | } | |||
| 1230 | ||||
| 1231 | /// Find an iterator for inserting a DBG_VALUE instruction. | |||
| 1232 | static MachineBasicBlock::iterator | |||
| 1233 | findInsertLocation(MachineBasicBlock *MBB, SlotIndex Idx, | |||
| 1234 | LiveIntervals &LIS) { | |||
| 1235 | SlotIndex Start = LIS.getMBBStartIdx(MBB); | |||
| 1236 | Idx = Idx.getBaseIndex(); | |||
| 1237 | ||||
| 1238 | // Try to find an insert location by going backwards from Idx. | |||
| 1239 | MachineInstr *MI; | |||
| 1240 | while (!(MI = LIS.getInstructionFromIndex(Idx))) { | |||
| 1241 | // We've reached the beginning of MBB. | |||
| 1242 | if (Idx == Start) { | |||
| 1243 | MachineBasicBlock::iterator I = MBB->SkipPHIsLabelsAndDebug(MBB->begin()); | |||
| 1244 | return I; | |||
| 1245 | } | |||
| 1246 | Idx = Idx.getPrevIndex(); | |||
| 1247 | } | |||
| 1248 | ||||
| 1249 | // Don't insert anything after the first terminator, though. | |||
| 1250 | return MI->isTerminator() ? MBB->getFirstTerminator() : | |||
| 1251 | std::next(MachineBasicBlock::iterator(MI)); | |||
| 1252 | } | |||
| 1253 | ||||
| 1254 | /// Find an iterator for inserting the next DBG_VALUE instruction | |||
| 1255 | /// (or end if no more insert locations found). | |||
| 1256 | static MachineBasicBlock::iterator | |||
| 1257 | findNextInsertLocation(MachineBasicBlock *MBB, | |||
| 1258 | MachineBasicBlock::iterator I, | |||
| 1259 | SlotIndex StopIdx, MachineOperand &LocMO, | |||
| 1260 | LiveIntervals &LIS, | |||
| 1261 | const TargetRegisterInfo &TRI) { | |||
| 1262 | if (!LocMO.isReg()) | |||
| 1263 | return MBB->instr_end(); | |||
| 1264 | Register Reg = LocMO.getReg(); | |||
| 1265 | ||||
| 1266 | // Find the next instruction in the MBB that define the register Reg. | |||
| 1267 | while (I != MBB->end() && !I->isTerminator()) { | |||
| 1268 | if (!LIS.isNotInMIMap(*I) && | |||
| 1269 | SlotIndex::isEarlierEqualInstr(StopIdx, LIS.getInstructionIndex(*I))) | |||
| 1270 | break; | |||
| 1271 | if (I->definesRegister(Reg, &TRI)) | |||
| 1272 | // The insert location is directly after the instruction/bundle. | |||
| 1273 | return std::next(I); | |||
| 1274 | ++I; | |||
| 1275 | } | |||
| 1276 | return MBB->end(); | |||
| 1277 | } | |||
| 1278 | ||||
| 1279 | void UserValue::insertDebugValue(MachineBasicBlock *MBB, SlotIndex StartIdx, | |||
| 1280 | SlotIndex StopIdx, DbgValueLocation Loc, | |||
| 1281 | bool Spilled, unsigned SpillOffset, | |||
| 1282 | LiveIntervals &LIS, const TargetInstrInfo &TII, | |||
| 1283 | const TargetRegisterInfo &TRI) { | |||
| 1284 | SlotIndex MBBEndIdx = LIS.getMBBEndIdx(&*MBB); | |||
| 1285 | // Only search within the current MBB. | |||
| 1286 | StopIdx = (MBBEndIdx < StopIdx) ? MBBEndIdx : StopIdx; | |||
| 1287 | MachineBasicBlock::iterator I = findInsertLocation(MBB, StartIdx, LIS); | |||
| 1288 | // Undef values don't exist in locations so create new "noreg" register MOs | |||
| 1289 | // for them. See getLocationNo(). | |||
| 1290 | MachineOperand MO = !Loc.isUndef() ? | |||
| 1291 | locations[Loc.locNo()] : | |||
| 1292 | MachineOperand::CreateReg(/* Reg */ 0, /* isDef */ false, /* isImp */ false, | |||
| 1293 | /* isKill */ false, /* isDead */ false, | |||
| 1294 | /* isUndef */ false, /* isEarlyClobber */ false, | |||
| 1295 | /* SubReg */ 0, /* isDebug */ true); | |||
| 1296 | ||||
| 1297 | ++NumInsertedDebugValues; | |||
| 1298 | ||||
| 1299 | assert(cast<DILocalVariable>(Variable)((cast<DILocalVariable>(Variable) ->isValidLocationForIntrinsic (getDebugLoc()) && "Expected inlined-at fields to agree" ) ? static_cast<void> (0) : __assert_fail ("cast<DILocalVariable>(Variable) ->isValidLocationForIntrinsic(getDebugLoc()) && \"Expected inlined-at fields to agree\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 1301, __PRETTY_FUNCTION__)) | |||
| 1300 | ->isValidLocationForIntrinsic(getDebugLoc()) &&((cast<DILocalVariable>(Variable) ->isValidLocationForIntrinsic (getDebugLoc()) && "Expected inlined-at fields to agree" ) ? static_cast<void> (0) : __assert_fail ("cast<DILocalVariable>(Variable) ->isValidLocationForIntrinsic(getDebugLoc()) && \"Expected inlined-at fields to agree\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 1301, __PRETTY_FUNCTION__)) | |||
| 1301 | "Expected inlined-at fields to agree")((cast<DILocalVariable>(Variable) ->isValidLocationForIntrinsic (getDebugLoc()) && "Expected inlined-at fields to agree" ) ? static_cast<void> (0) : __assert_fail ("cast<DILocalVariable>(Variable) ->isValidLocationForIntrinsic(getDebugLoc()) && \"Expected inlined-at fields to agree\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 1301, __PRETTY_FUNCTION__)); | |||
| 1302 | ||||
| 1303 | // If the location was spilled, the new DBG_VALUE will be indirect. If the | |||
| 1304 | // original DBG_VALUE was indirect, we need to add DW_OP_deref to indicate | |||
| 1305 | // that the original virtual register was a pointer. Also, add the stack slot | |||
| 1306 | // offset for the spilled register to the expression. | |||
| 1307 | const DIExpression *Expr = Expression; | |||
| 1308 | if (Spilled) | |||
| 1309 | Expr = DIExpression::prepend(Expr, DIExpression::ApplyOffset, SpillOffset); | |||
| 1310 | ||||
| 1311 | assert((!Spilled || MO.isFI()) && "a spilled location must be a frame index")(((!Spilled || MO.isFI()) && "a spilled location must be a frame index" ) ? static_cast<void> (0) : __assert_fail ("(!Spilled || MO.isFI()) && \"a spilled location must be a frame index\"" , "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/CodeGen/LiveDebugVariables.cpp" , 1311, __PRETTY_FUNCTION__)); | |||
| 1312 | ||||
| 1313 | do { | |||
| 1314 | BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_VALUE), | |||
| 1315 | Spilled, MO, Variable, Expr); | |||
| 1316 | ||||
| 1317 | // Continue and insert DBG_VALUES after every redefinition of register | |||
| 1318 | // associated with the debug value within the range | |||
| 1319 | I = findNextInsertLocation(MBB, I, StopIdx, MO, LIS, TRI); | |||
| 1320 | } while (I != MBB->end()); | |||
| 1321 | } | |||
| 1322 | ||||
| 1323 | void UserLabel::insertDebugLabel(MachineBasicBlock *MBB, SlotIndex Idx, | |||
| 1324 | LiveIntervals &LIS, | |||
| 1325 | const TargetInstrInfo &TII) { | |||
| 1326 | MachineBasicBlock::iterator I = findInsertLocation(MBB, Idx, LIS); | |||
| 1327 | ++NumInsertedDebugLabels; | |||
| 1328 | BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_LABEL)) | |||
| 1329 | .addMetadata(Label); | |||
| 1330 | } | |||
| 1331 | ||||
| 1332 | void UserValue::emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS, | |||
| 1333 | const TargetInstrInfo &TII, | |||
| 1334 | const TargetRegisterInfo &TRI, | |||
| 1335 | const SpillOffsetMap &SpillOffsets) { | |||
| 1336 | MachineFunction::iterator MFEnd = VRM->getMachineFunction().end(); | |||
| 1337 | ||||
| 1338 | for (LocMap::const_iterator I = locInts.begin(); I.valid();) { | |||
| 1339 | SlotIndex Start = I.start(); | |||
| 1340 | SlotIndex Stop = I.stop(); | |||
| 1341 | DbgValueLocation Loc = I.value(); | |||
| 1342 | auto SpillIt = | |||
| 1343 | !Loc.isUndef() ? SpillOffsets.find(Loc.locNo()) : SpillOffsets.end(); | |||
| 1344 | bool Spilled = SpillIt != SpillOffsets.end(); | |||
| 1345 | unsigned SpillOffset = Spilled ? SpillIt->second : 0; | |||
| 1346 | ||||
| 1347 | LLVM_DEBUG(dbgs() << "\t[" << Start << ';' << Stop << "):" << Loc.locNo())do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "\t[" << Start << ';' << Stop << "):" << Loc.locNo(); } } while (false); | |||
| 1348 | MachineFunction::iterator MBB = LIS.getMBBFromIndex(Start)->getIterator(); | |||
| 1349 | SlotIndex MBBEnd = LIS.getMBBEndIdx(&*MBB); | |||
| 1350 | ||||
| 1351 | LLVM_DEBUG(dbgs() << ' ' << printMBBReference(*MBB) << '-' << MBBEnd)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << ' ' << printMBBReference (*MBB) << '-' << MBBEnd; } } while (false); | |||
| 1352 | insertDebugValue(&*MBB, Start, Stop, Loc, Spilled, SpillOffset, LIS, TII, | |||
| 1353 | TRI); | |||
| 1354 | // This interval may span multiple basic blocks. | |||
| 1355 | // Insert a DBG_VALUE into each one. | |||
| 1356 | while (Stop > MBBEnd) { | |||
| 1357 | // Move to the next block. | |||
| 1358 | Start = MBBEnd; | |||
| 1359 | if (++MBB == MFEnd) | |||
| 1360 | break; | |||
| 1361 | MBBEnd = LIS.getMBBEndIdx(&*MBB); | |||
| 1362 | LLVM_DEBUG(dbgs() << ' ' << printMBBReference(*MBB) << '-' << MBBEnd)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << ' ' << printMBBReference (*MBB) << '-' << MBBEnd; } } while (false); | |||
| 1363 | insertDebugValue(&*MBB, Start, Stop, Loc, Spilled, SpillOffset, LIS, TII, | |||
| 1364 | TRI); | |||
| 1365 | } | |||
| 1366 | LLVM_DEBUG(dbgs() << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << '\n'; } } while (false); | |||
| 1367 | if (MBB == MFEnd) | |||
| 1368 | break; | |||
| 1369 | ||||
| 1370 | ++I; | |||
| 1371 | } | |||
| 1372 | } | |||
| 1373 | ||||
| 1374 | void UserLabel::emitDebugLabel(LiveIntervals &LIS, const TargetInstrInfo &TII) { | |||
| 1375 | LLVM_DEBUG(dbgs() << "\t" << loc)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "\t" << loc; } } while (false); | |||
| 1376 | MachineFunction::iterator MBB = LIS.getMBBFromIndex(loc)->getIterator(); | |||
| 1377 | ||||
| 1378 | LLVM_DEBUG(dbgs() << ' ' << printMBBReference(*MBB))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << ' ' << printMBBReference (*MBB); } } while (false); | |||
| 1379 | insertDebugLabel(&*MBB, loc, LIS, TII); | |||
| 1380 | ||||
| 1381 | LLVM_DEBUG(dbgs() << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << '\n'; } } while (false); | |||
| 1382 | } | |||
| 1383 | ||||
| 1384 | void LDVImpl::emitDebugValues(VirtRegMap *VRM) { | |||
| 1385 | LLVM_DEBUG(dbgs() << "********** EMITTING LIVE DEBUG VARIABLES **********\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "********** EMITTING LIVE DEBUG VARIABLES **********\n" ; } } while (false); | |||
| 1386 | if (!MF) | |||
| 1387 | return; | |||
| 1388 | const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo(); | |||
| 1389 | SpillOffsetMap SpillOffsets; | |||
| 1390 | for (auto &userValue : userValues) { | |||
| 1391 | LLVM_DEBUG(userValue->print(dbgs(), TRI))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { userValue->print(dbgs(), TRI); } } while (false); | |||
| 1392 | userValue->rewriteLocations(*VRM, *MF, *TII, *TRI, SpillOffsets); | |||
| 1393 | userValue->emitDebugValues(VRM, *LIS, *TII, *TRI, SpillOffsets); | |||
| 1394 | } | |||
| 1395 | LLVM_DEBUG(dbgs() << "********** EMITTING LIVE DEBUG LABELS **********\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { dbgs() << "********** EMITTING LIVE DEBUG LABELS **********\n" ; } } while (false); | |||
| 1396 | for (auto &userLabel : userLabels) { | |||
| 1397 | LLVM_DEBUG(userLabel->print(dbgs(), TRI))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("livedebugvars")) { userLabel->print(dbgs(), TRI); } } while (false); | |||
| 1398 | userLabel->emitDebugLabel(*LIS, *TII); | |||
| 1399 | } | |||
| 1400 | EmitDone = true; | |||
| 1401 | } | |||
| 1402 | ||||
| 1403 | void LiveDebugVariables::emitDebugValues(VirtRegMap *VRM) { | |||
| 1404 | if (pImpl) | |||
| 1405 | static_cast<LDVImpl*>(pImpl)->emitDebugValues(VRM); | |||
| 1406 | } | |||
| 1407 | ||||
| 1408 | bool LiveDebugVariables::doInitialization(Module &M) { | |||
| 1409 | return Pass::doInitialization(M); | |||
| 1410 | } | |||
| 1411 | ||||
| 1412 | #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) | |||
| 1413 | LLVM_DUMP_METHOD__attribute__((noinline)) __attribute__((__used__)) void LiveDebugVariables::dump() const { | |||
| 1414 | if (pImpl) | |||
| ||||
| 1415 | static_cast<LDVImpl*>(pImpl)->print(dbgs()); | |||
| 1416 | } | |||
| 1417 | #endif |