1 //===-- Passes.h - Target independent code generation passes ----*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 // This file defines interfaces to access the target independent code generation
10 // passes provided by the LLVM backend.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CODEGEN_PASSES_H
15 #define LLVM_CODEGEN_PASSES_H
23 class MachineFunction
;
24 class MachineFunctionPass
;
28 class TargetRegisterClass
;
31 } // End llvm namespace
33 /// List of target independent CodeGen pass IDs.
35 FunctionPass
*createAtomicExpandPass();
37 /// createUnreachableBlockEliminationPass - The LLVM code generator does not
38 /// work well with unreachable basic blocks (what live ranges make sense for a
39 /// block that cannot be reached?). As such, a code generator should either
40 /// not instruction select unreachable blocks, or run this pass as its
41 /// last LLVM modifying pass to clean up blocks that are not reachable from
43 FunctionPass
*createUnreachableBlockEliminationPass();
45 /// MachineFunctionPrinter pass - This pass prints out the machine function to
46 /// the given stream as a debugging tool.
48 createMachineFunctionPrinterPass(raw_ostream
&OS
,
49 const std::string
&Banner
="");
51 /// MIRPrinting pass - this pass prints out the LLVM IR into the given stream
52 /// using the MIR serialization format.
53 MachineFunctionPass
*createPrintMIRPass(raw_ostream
&OS
);
55 /// This pass resets a MachineFunction when it has the FailedISel property
56 /// as if it was just created.
57 /// If EmitFallbackDiag is true, the pass will emit a
58 /// DiagnosticInfoISelFallback for every MachineFunction it resets.
59 /// If AbortOnFailedISel is true, abort compilation instead of resetting.
60 MachineFunctionPass
*createResetMachineFunctionPass(bool EmitFallbackDiag
,
61 bool AbortOnFailedISel
);
63 /// createCodeGenPreparePass - Transform the code to expose more pattern
64 /// matching during instruction selection.
65 FunctionPass
*createCodeGenPreparePass();
67 /// createScalarizeMaskedMemIntrinPass - Replace masked load, store, gather
68 /// and scatter intrinsics with scalar code when target doesn't support them.
69 FunctionPass
*createScalarizeMaskedMemIntrinPass();
71 /// AtomicExpandID -- Lowers atomic operations in terms of either cmpxchg
72 /// load-linked/store-conditional loops.
73 extern char &AtomicExpandID
;
75 /// MachineLoopInfo - This pass is a loop analysis pass.
76 extern char &MachineLoopInfoID
;
78 /// MachineDominators - This pass is a machine dominators analysis pass.
79 extern char &MachineDominatorsID
;
81 /// MachineDominanaceFrontier - This pass is a machine dominators analysis pass.
82 extern char &MachineDominanceFrontierID
;
84 /// MachineRegionInfo - This pass computes SESE regions for machine functions.
85 extern char &MachineRegionInfoPassID
;
87 /// EdgeBundles analysis - Bundle machine CFG edges.
88 extern char &EdgeBundlesID
;
90 /// LiveVariables pass - This pass computes the set of blocks in which each
91 /// variable is life and sets machine operand kill flags.
92 extern char &LiveVariablesID
;
94 /// PHIElimination - This pass eliminates machine instruction PHI nodes
95 /// by inserting copy instructions. This destroys SSA information, but is the
96 /// desired input for some register allocators. This pass is "required" by
97 /// these register allocator like this: AU.addRequiredID(PHIEliminationID);
98 extern char &PHIEliminationID
;
100 /// LiveIntervals - This analysis keeps track of the live ranges of virtual
101 /// and physical registers.
102 extern char &LiveIntervalsID
;
104 /// LiveStacks pass. An analysis keeping track of the liveness of stack slots.
105 extern char &LiveStacksID
;
107 /// TwoAddressInstruction - This pass reduces two-address instructions to
108 /// use two operands. This destroys SSA information but it is desired by
109 /// register allocators.
110 extern char &TwoAddressInstructionPassID
;
112 /// ProcessImpicitDefs pass - This pass removes IMPLICIT_DEFs.
113 extern char &ProcessImplicitDefsID
;
115 /// RegisterCoalescer - This pass merges live ranges to eliminate copies.
116 extern char &RegisterCoalescerID
;
118 /// MachineScheduler - This pass schedules machine instructions.
119 extern char &MachineSchedulerID
;
121 /// PostMachineScheduler - This pass schedules machine instructions postRA.
122 extern char &PostMachineSchedulerID
;
124 /// SpillPlacement analysis. Suggest optimal placement of spill code between
126 extern char &SpillPlacementID
;
128 /// ShrinkWrap pass. Look for the best place to insert save and restore
129 // instruction and update the MachineFunctionInfo with that information.
130 extern char &ShrinkWrapID
;
132 /// LiveRangeShrink pass. Move instruction close to its definition to shrink
133 /// the definition's live range.
134 extern char &LiveRangeShrinkID
;
136 /// Greedy register allocator.
137 extern char &RAGreedyID
;
139 /// Basic register allocator.
140 extern char &RABasicID
;
142 /// VirtRegRewriter pass. Rewrite virtual registers to physical registers as
143 /// assigned in VirtRegMap.
144 extern char &VirtRegRewriterID
;
146 /// UnreachableMachineBlockElimination - This pass removes unreachable
147 /// machine basic blocks.
148 extern char &UnreachableMachineBlockElimID
;
150 /// DeadMachineInstructionElim - This pass removes dead machine instructions.
151 extern char &DeadMachineInstructionElimID
;
153 /// This pass adds dead/undef flags after analyzing subregister lanes.
154 extern char &DetectDeadLanesID
;
156 /// This pass perform post-ra machine sink for COPY instructions.
157 extern char &PostRAMachineSinkingID
;
159 /// FastRegisterAllocation Pass - This pass register allocates as fast as
160 /// possible. It is best suited for debug code where live ranges are short.
162 FunctionPass
*createFastRegisterAllocator();
164 /// BasicRegisterAllocation Pass - This pass implements a degenerate global
165 /// register allocator using the basic regalloc framework.
167 FunctionPass
*createBasicRegisterAllocator();
169 /// Greedy register allocation pass - This pass implements a global register
170 /// allocator for optimized builds.
172 FunctionPass
*createGreedyRegisterAllocator();
174 /// PBQPRegisterAllocation Pass - This pass implements the Partitioned Boolean
175 /// Quadratic Prograaming (PBQP) based register allocator.
177 FunctionPass
*createDefaultPBQPRegisterAllocator();
179 /// PrologEpilogCodeInserter - This pass inserts prolog and epilog code,
180 /// and eliminates abstract frame references.
181 extern char &PrologEpilogCodeInserterID
;
182 MachineFunctionPass
*createPrologEpilogInserterPass();
184 /// ExpandPostRAPseudos - This pass expands pseudo instructions after
185 /// register allocation.
186 extern char &ExpandPostRAPseudosID
;
188 /// createPostRAHazardRecognizer - This pass runs the post-ra hazard
190 extern char &PostRAHazardRecognizerID
;
192 /// createPostRAScheduler - This pass performs post register allocation
194 extern char &PostRASchedulerID
;
196 /// BranchFolding - This pass performs machine code CFG based
197 /// optimizations to delete branches to branches, eliminate branches to
198 /// successor blocks (creating fall throughs), and eliminating branches over
200 extern char &BranchFolderPassID
;
202 /// BranchRelaxation - This pass replaces branches that need to jump further
203 /// than is supported by a branch instruction.
204 extern char &BranchRelaxationPassID
;
206 /// MachineFunctionPrinterPass - This pass prints out MachineInstr's.
207 extern char &MachineFunctionPrinterPassID
;
209 /// MIRPrintingPass - this pass prints out the LLVM IR using the MIR
210 /// serialization format.
211 extern char &MIRPrintingPassID
;
213 /// TailDuplicate - Duplicate blocks with unconditional branches
214 /// into tails of their predecessors.
215 extern char &TailDuplicateID
;
217 /// Duplicate blocks with unconditional branches into tails of their
218 /// predecessors. Variant that works before register allocation.
219 extern char &EarlyTailDuplicateID
;
221 /// MachineTraceMetrics - This pass computes critical path and CPU resource
222 /// usage in an ensemble of traces.
223 extern char &MachineTraceMetricsID
;
225 /// EarlyIfConverter - This pass performs if-conversion on SSA form by
226 /// inserting cmov instructions.
227 extern char &EarlyIfConverterID
;
229 /// EarlyIfPredicator - This pass performs if-conversion on SSA form by
230 /// predicating if/else block and insert select at the join point.
231 extern char &EarlyIfPredicatorID
;
233 /// This pass performs instruction combining using trace metrics to estimate
234 /// critical-path and resource depth.
235 extern char &MachineCombinerID
;
237 /// StackSlotColoring - This pass performs stack coloring and merging.
238 /// It merges disjoint allocas to reduce the stack size.
239 extern char &StackColoringID
;
241 /// IfConverter - This pass performs machine code if conversion.
242 extern char &IfConverterID
;
244 FunctionPass
*createIfConverter(
245 std::function
<bool(const MachineFunction
&)> Ftor
);
247 /// MachineBlockPlacement - This pass places basic blocks based on branch
249 extern char &MachineBlockPlacementID
;
251 /// MachineBlockPlacementStats - This pass collects statistics about the
252 /// basic block placement using branch probabilities and block frequency
254 extern char &MachineBlockPlacementStatsID
;
256 /// GCLowering Pass - Used by gc.root to perform its default lowering
258 FunctionPass
*createGCLoweringPass();
260 /// ShadowStackGCLowering - Implements the custom lowering mechanism
261 /// used by the shadow stack GC. Only runs on functions which opt in to
262 /// the shadow stack collector.
263 FunctionPass
*createShadowStackGCLoweringPass();
265 /// GCMachineCodeAnalysis - Target-independent pass to mark safe points
266 /// in machine code. Must be added very late during code generation, just
267 /// prior to output, and importantly after all CFG transformations (such as
269 extern char &GCMachineCodeAnalysisID
;
271 /// Creates a pass to print GC metadata.
273 FunctionPass
*createGCInfoPrinter(raw_ostream
&OS
);
275 /// MachineCSE - This pass performs global CSE on machine instructions.
276 extern char &MachineCSEID
;
278 /// ImplicitNullChecks - This pass folds null pointer checks into nearby
279 /// memory operations.
280 extern char &ImplicitNullChecksID
;
282 /// This pass performs loop invariant code motion on machine instructions.
283 extern char &MachineLICMID
;
285 /// This pass performs loop invariant code motion on machine instructions.
286 /// This variant works before register allocation. \see MachineLICMID.
287 extern char &EarlyMachineLICMID
;
289 /// MachineSinking - This pass performs sinking on machine instructions.
290 extern char &MachineSinkingID
;
292 /// MachineCopyPropagation - This pass performs copy propagation on
293 /// machine instructions.
294 extern char &MachineCopyPropagationID
;
296 /// PeepholeOptimizer - This pass performs peephole optimizations -
297 /// like extension and comparison eliminations.
298 extern char &PeepholeOptimizerID
;
300 /// OptimizePHIs - This pass optimizes machine instruction PHIs
301 /// to take advantage of opportunities created during DAG legalization.
302 extern char &OptimizePHIsID
;
304 /// StackSlotColoring - This pass performs stack slot coloring.
305 extern char &StackSlotColoringID
;
307 /// This pass lays out funclets contiguously.
308 extern char &FuncletLayoutID
;
310 /// This pass inserts the XRay instrumentation sleds if they are supported by
311 /// the target platform.
312 extern char &XRayInstrumentationID
;
314 /// This pass inserts FEntry calls
315 extern char &FEntryInserterID
;
317 /// This pass implements the "patchable-function" attribute.
318 extern char &PatchableFunctionID
;
320 /// createStackProtectorPass - This pass adds stack protectors to functions.
322 FunctionPass
*createStackProtectorPass();
324 /// createMachineVerifierPass - This pass verifies cenerated machine code
325 /// instructions for correctness.
327 FunctionPass
*createMachineVerifierPass(const std::string
& Banner
);
329 /// createDwarfEHPass - This pass mulches exception handling code into a form
330 /// adapted to code generation. Required if using dwarf exception handling.
331 FunctionPass
*createDwarfEHPass();
333 /// createWinEHPass - Prepares personality functions used by MSVC on Windows,
334 /// in addition to the Itanium LSDA based personalities.
335 FunctionPass
*createWinEHPass(bool DemoteCatchSwitchPHIOnly
= false);
337 /// createSjLjEHPreparePass - This pass adapts exception handling code to use
338 /// the GCC-style builtin setjmp/longjmp (sjlj) to handling EH control flow.
340 FunctionPass
*createSjLjEHPreparePass();
342 /// createWasmEHPass - This pass adapts exception handling code to use
343 /// WebAssembly's exception handling scheme.
344 FunctionPass
*createWasmEHPass();
346 /// LocalStackSlotAllocation - This pass assigns local frame indices to stack
347 /// slots relative to one another and allocates base registers to access them
348 /// when it is estimated by the target to be out of range of normal frame
349 /// pointer or stack pointer index addressing.
350 extern char &LocalStackSlotAllocationID
;
352 /// This pass expands pseudo-instructions, reserves registers and adjusts
353 /// machine frame information.
354 extern char &FinalizeISelID
;
356 /// UnpackMachineBundles - This pass unpack machine instruction bundles.
357 extern char &UnpackMachineBundlesID
;
360 createUnpackMachineBundles(std::function
<bool(const MachineFunction
&)> Ftor
);
362 /// FinalizeMachineBundles - This pass finalize machine instruction
363 /// bundles (created earlier, e.g. during pre-RA scheduling).
364 extern char &FinalizeMachineBundlesID
;
366 /// StackMapLiveness - This pass analyses the register live-out set of
367 /// stackmap/patchpoint intrinsics and attaches the calculated information to
368 /// the intrinsic for later emission to the StackMap.
369 extern char &StackMapLivenessID
;
371 /// LiveDebugValues pass
372 extern char &LiveDebugValuesID
;
374 /// createJumpInstrTables - This pass creates jump-instruction tables.
375 ModulePass
*createJumpInstrTablesPass();
377 /// createForwardControlFlowIntegrityPass - This pass adds control-flow
379 ModulePass
*createForwardControlFlowIntegrityPass();
381 /// InterleavedAccess Pass - This pass identifies and matches interleaved
382 /// memory accesses to target specific intrinsics.
384 FunctionPass
*createInterleavedAccessPass();
386 /// InterleavedLoadCombines Pass - This pass identifies interleaved loads and
387 /// combines them into wide loads detectable by InterleavedAccessPass
389 FunctionPass
*createInterleavedLoadCombinePass();
391 /// LowerEmuTLS - This pass generates __emutls_[vt].xyz variables for all
392 /// TLS variables for the emulated TLS model.
394 ModulePass
*createLowerEmuTLSPass();
396 /// This pass lowers the \@llvm.load.relative and \@llvm.objc.* intrinsics to
397 /// instructions. This is unsafe to do earlier because a pass may combine the
398 /// constant initializer into the load, which may result in an overflowing
400 ModulePass
*createPreISelIntrinsicLoweringPass();
402 /// GlobalMerge - This pass merges internal (by default) globals into structs
403 /// to enable reuse of a base pointer by indexed addressing modes.
404 /// It can also be configured to focus on size optimizations only.
406 Pass
*createGlobalMergePass(const TargetMachine
*TM
, unsigned MaximalOffset
,
407 bool OnlyOptimizeForSize
= false,
408 bool MergeExternalByDefault
= false);
410 /// This pass splits the stack into a safe stack and an unsafe stack to
411 /// protect against stack-based overflow vulnerabilities.
412 FunctionPass
*createSafeStackPass();
414 /// This pass detects subregister lanes in a virtual register that are used
415 /// independently of other lanes and splits them into separate virtual
417 extern char &RenameIndependentSubregsID
;
419 /// This pass is executed POST-RA to collect which physical registers are
420 /// preserved by given machine function.
421 FunctionPass
*createRegUsageInfoCollector();
423 /// Return a MachineFunction pass that identifies call sites
424 /// and propagates register usage information of callee to caller
425 /// if available with PysicalRegisterUsageInfo pass.
426 FunctionPass
*createRegUsageInfoPropPass();
428 /// This pass performs software pipelining on machine instructions.
429 extern char &MachinePipelinerID
;
431 /// This pass frees the memory occupied by the MachineFunction.
432 FunctionPass
*createFreeMachineFunctionPass();
434 /// This pass performs outlining on machine instructions directly before
435 /// printing assembly.
436 ModulePass
*createMachineOutlinerPass(bool RunOnAllFunctions
= true);
438 /// This pass expands the experimental reduction intrinsics into sequences of
440 FunctionPass
*createExpandReductionsPass();
442 // This pass expands memcmp() to load/stores.
443 FunctionPass
*createExpandMemCmpPass();
445 /// Creates Break False Dependencies pass. \see BreakFalseDeps.cpp
446 FunctionPass
*createBreakFalseDeps();
448 // This pass expands indirectbr instructions.
449 FunctionPass
*createIndirectBrExpandPass();
451 /// Creates CFI Instruction Inserter pass. \see CFIInstrInserter.cpp
452 FunctionPass
*createCFIInstrInserter();
454 /// Create Hardware Loop pass. \see HardwareLoops.cpp
455 FunctionPass
*createHardwareLoopsPass();
457 } // End llvm namespace