1 //===- Deserializer.h - MLIR SPIR-V Deserializer ----------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file declares the SPIR-V binary to MLIR SPIR-V module deserializer.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef MLIR_TARGET_SPIRV_DESERIALIZER_H
14 #define MLIR_TARGET_SPIRV_DESERIALIZER_H
15 
16 #include "mlir/Dialect/SPIRV/IR/SPIRVEnums.h"
17 #include "mlir/Dialect/SPIRV/IR/SPIRVOps.h"
18 #include "mlir/IR/Builders.h"
19 #include "llvm/ADT/ArrayRef.h"
20 #include "llvm/ADT/SetVector.h"
21 #include "llvm/ADT/StringRef.h"
22 #include "llvm/Support/ScopedPrinter.h"
23 #include <cstdint>
24 
25 namespace mlir {
26 namespace spirv {
27 
28 //===----------------------------------------------------------------------===//
29 // Utility Definitions
30 //===----------------------------------------------------------------------===//
31 
32 /// A struct for containing a header block's merge and continue targets.
33 ///
34 /// This struct is used to track original structured control flow info from
35 /// SPIR-V blob. This info will be used to create
36 /// spv.mlir.selection/spv.mlir.loop later.
37 struct BlockMergeInfo {
38   Block *mergeBlock;
39   Block *continueBlock; // nullptr for spv.mlir.selection
40   Location loc;
41   uint32_t control; // Selection/loop control
42 
BlockMergeInfoBlockMergeInfo43   BlockMergeInfo(Location location, uint32_t control)
44       : mergeBlock(nullptr), continueBlock(nullptr), loc(location),
45         control(control) {}
46   BlockMergeInfo(Location location, uint32_t control, Block *m,
47                  Block *c = nullptr)
mergeBlockBlockMergeInfo48       : mergeBlock(m), continueBlock(c), loc(location), control(control) {}
49 };
50 
51 /// A struct for containing OpLine instruction information.
52 struct DebugLine {
53   uint32_t fileID;
54   uint32_t line;
55   uint32_t column;
56 };
57 
58 /// Map from a selection/loop's header block to its merge (and continue) target.
59 using BlockMergeInfoMap = DenseMap<Block *, BlockMergeInfo>;
60 
61 /// A "deferred struct type" is a struct type with one or more member types not
62 /// known when the Deserializer first encounters the struct. This happens, for
63 /// example, with recursive structs where a pointer to the struct type is
64 /// forward declared through OpTypeForwardPointer in the SPIR-V module before
65 /// the struct declaration; the actual pointer to struct type should be defined
66 /// later through an OpTypePointer. For example, the following C struct:
67 ///
68 /// struct A {
69 ///   A* next;
70 /// };
71 ///
72 /// would be represented in the SPIR-V module as:
73 ///
74 /// OpName %A "A"
75 /// OpTypeForwardPointer %APtr Generic
76 /// %A = OpTypeStruct %APtr
77 /// %APtr = OpTypePointer Generic %A
78 ///
79 /// This means that the spirv::StructType cannot be fully constructed directly
80 /// when the Deserializer encounters it. Instead we create a
81 /// DeferredStructTypeInfo that contains all the information we know about the
82 /// spirv::StructType. Once all forward references for the struct are resolved,
83 /// the struct's body is set with all member info.
84 struct DeferredStructTypeInfo {
85   spirv::StructType deferredStructType;
86 
87   // A list of all unresolved member types for the struct. First element of each
88   // item is operand ID, second element is member index in the struct.
89   SmallVector<std::pair<uint32_t, unsigned>, 0> unresolvedMemberTypes;
90 
91   // The list of member types. For unresolved members, this list contains
92   // place-holder empty types that will be updated later.
93   SmallVector<Type, 4> memberTypes;
94   SmallVector<spirv::StructType::OffsetInfo, 0> offsetInfo;
95   SmallVector<spirv::StructType::MemberDecorationInfo, 0> memberDecorationsInfo;
96 };
97 
98 /// A struct that collects the info needed to materialize/emit a
99 /// SpecConstantOperation op.
100 struct SpecConstOperationMaterializationInfo {
101   spirv::Opcode enclodesOpcode;
102   uint32_t resultTypeID;
103   SmallVector<uint32_t> enclosedOpOperands;
104 };
105 
106 //===----------------------------------------------------------------------===//
107 // Deserializer Declaration
108 //===----------------------------------------------------------------------===//
109 
110 /// A SPIR-V module serializer.
111 ///
112 /// A SPIR-V binary module is a single linear stream of instructions; each
113 /// instruction is composed of 32-bit words. The first word of an instruction
114 /// records the total number of words of that instruction using the 16
115 /// higher-order bits. So this deserializer uses that to get instruction
116 /// boundary and parse instructions and build a SPIR-V ModuleOp gradually.
117 ///
118 // TODO: clean up created ops on errors
119 class Deserializer {
120 public:
121   /// Creates a deserializer for the given SPIR-V `binary` module.
122   /// The SPIR-V ModuleOp will be created into `context.
123   explicit Deserializer(ArrayRef<uint32_t> binary, MLIRContext *context);
124 
125   /// Deserializes the remembered SPIR-V binary module.
126   LogicalResult deserialize();
127 
128   /// Collects the final SPIR-V ModuleOp.
129   OwningOpRef<spirv::ModuleOp> collect();
130 
131 private:
132   //===--------------------------------------------------------------------===//
133   // Module structure
134   //===--------------------------------------------------------------------===//
135 
136   /// Initializes the `module` ModuleOp in this deserializer instance.
137   OwningOpRef<spirv::ModuleOp> createModuleOp();
138 
139   /// Processes SPIR-V module header in `binary`.
140   LogicalResult processHeader();
141 
142   /// Processes the SPIR-V OpCapability with `operands` and updates bookkeeping
143   /// in the deserializer.
144   LogicalResult processCapability(ArrayRef<uint32_t> operands);
145 
146   /// Processes the SPIR-V OpExtension with `operands` and updates bookkeeping
147   /// in the deserializer.
148   LogicalResult processExtension(ArrayRef<uint32_t> words);
149 
150   /// Processes the SPIR-V OpExtInstImport with `operands` and updates
151   /// bookkeeping in the deserializer.
152   LogicalResult processExtInstImport(ArrayRef<uint32_t> words);
153 
154   /// Attaches (version, capabilities, extensions) triple to `module` as an
155   /// attribute.
156   void attachVCETriple();
157 
158   /// Processes the SPIR-V OpMemoryModel with `operands` and updates `module`.
159   LogicalResult processMemoryModel(ArrayRef<uint32_t> operands);
160 
161   /// Process SPIR-V OpName with `operands`.
162   LogicalResult processName(ArrayRef<uint32_t> operands);
163 
164   /// Processes an OpDecorate instruction.
165   LogicalResult processDecoration(ArrayRef<uint32_t> words);
166 
167   // Processes an OpMemberDecorate instruction.
168   LogicalResult processMemberDecoration(ArrayRef<uint32_t> words);
169 
170   /// Processes an OpMemberName instruction.
171   LogicalResult processMemberName(ArrayRef<uint32_t> words);
172 
173   /// Gets the function op associated with a result <id> of OpFunction.
getFunction(uint32_t id)174   spirv::FuncOp getFunction(uint32_t id) { return funcMap.lookup(id); }
175 
176   /// Processes the SPIR-V function at the current `offset` into `binary`.
177   /// The operands to the OpFunction instruction is passed in as ``operands`.
178   /// This method processes each instruction inside the function and dispatches
179   /// them to their handler method accordingly.
180   LogicalResult processFunction(ArrayRef<uint32_t> operands);
181 
182   /// Processes OpFunctionEnd and finalizes function. This wires up block
183   /// argument created from OpPhi instructions and also structurizes control
184   /// flow.
185   LogicalResult processFunctionEnd(ArrayRef<uint32_t> operands);
186 
187   /// Gets the constant's attribute and type associated with the given <id>.
188   Optional<std::pair<Attribute, Type>> getConstant(uint32_t id);
189 
190   /// Gets the info needed to materialize the spec constant operation op
191   /// associated with the given <id>.
192   Optional<SpecConstOperationMaterializationInfo>
193   getSpecConstantOperation(uint32_t id);
194 
195   /// Gets the constant's integer attribute with the given <id>. Returns a
196   /// null IntegerAttr if the given is not registered or does not correspond
197   /// to an integer constant.
198   IntegerAttr getConstantInt(uint32_t id);
199 
200   /// Returns a symbol to be used for the function name with the given
201   /// result <id>. This tries to use the function's OpName if
202   /// exists; otherwise creates one based on the <id>.
203   std::string getFunctionSymbol(uint32_t id);
204 
205   /// Returns a symbol to be used for the specialization constant with the given
206   /// result <id>. This tries to use the specialization constant's OpName if
207   /// exists; otherwise creates one based on the <id>.
208   std::string getSpecConstantSymbol(uint32_t id);
209 
210   /// Gets the specialization constant with the given result <id>.
getSpecConstant(uint32_t id)211   spirv::SpecConstantOp getSpecConstant(uint32_t id) {
212     return specConstMap.lookup(id);
213   }
214 
215   /// Gets the composite specialization constant with the given result <id>.
getSpecConstantComposite(uint32_t id)216   spirv::SpecConstantCompositeOp getSpecConstantComposite(uint32_t id) {
217     return specConstCompositeMap.lookup(id);
218   }
219 
220   /// Creates a spirv::SpecConstantOp.
221   spirv::SpecConstantOp createSpecConstant(Location loc, uint32_t resultID,
222                                            Attribute defaultValue);
223 
224   /// Processes the OpVariable instructions at current `offset` into `binary`.
225   /// It is expected that this method is used for variables that are to be
226   /// defined at module scope and will be deserialized into a spv.GlobalVariable
227   /// instruction.
228   LogicalResult processGlobalVariable(ArrayRef<uint32_t> operands);
229 
230   /// Gets the global variable associated with a result <id> of OpVariable.
getGlobalVariable(uint32_t id)231   spirv::GlobalVariableOp getGlobalVariable(uint32_t id) {
232     return globalVariableMap.lookup(id);
233   }
234 
235   //===--------------------------------------------------------------------===//
236   // Type
237   //===--------------------------------------------------------------------===//
238 
239   /// Gets type for a given result <id>.
getType(uint32_t id)240   Type getType(uint32_t id) { return typeMap.lookup(id); }
241 
242   /// Get the type associated with the result <id> of an OpUndef.
getUndefType(uint32_t id)243   Type getUndefType(uint32_t id) { return undefMap.lookup(id); }
244 
245   /// Returns true if the given `type` is for SPIR-V void type.
isVoidType(Type type)246   bool isVoidType(Type type) const { return type.isa<NoneType>(); }
247 
248   /// Processes a SPIR-V type instruction with given `opcode` and `operands` and
249   /// registers the type into `module`.
250   LogicalResult processType(spirv::Opcode opcode, ArrayRef<uint32_t> operands);
251 
252   LogicalResult processOpTypePointer(ArrayRef<uint32_t> operands);
253 
254   LogicalResult processArrayType(ArrayRef<uint32_t> operands);
255 
256   LogicalResult processCooperativeMatrixType(ArrayRef<uint32_t> operands);
257 
258   LogicalResult processFunctionType(ArrayRef<uint32_t> operands);
259 
260   LogicalResult processImageType(ArrayRef<uint32_t> operands);
261 
262   LogicalResult processSampledImageType(ArrayRef<uint32_t> operands);
263 
264   LogicalResult processRuntimeArrayType(ArrayRef<uint32_t> operands);
265 
266   LogicalResult processStructType(ArrayRef<uint32_t> operands);
267 
268   LogicalResult processMatrixType(ArrayRef<uint32_t> operands);
269 
270   LogicalResult processTypeForwardPointer(ArrayRef<uint32_t> operands);
271 
272   //===--------------------------------------------------------------------===//
273   // Constant
274   //===--------------------------------------------------------------------===//
275 
276   /// Processes a SPIR-V Op{|Spec}Constant instruction with the given
277   /// `operands`. `isSpec` indicates whether this is a specialization constant.
278   LogicalResult processConstant(ArrayRef<uint32_t> operands, bool isSpec);
279 
280   /// Processes a SPIR-V Op{|Spec}Constant{True|False} instruction with the
281   /// given `operands`. `isSpec` indicates whether this is a specialization
282   /// constant.
283   LogicalResult processConstantBool(bool isTrue, ArrayRef<uint32_t> operands,
284                                     bool isSpec);
285 
286   /// Processes a SPIR-V OpConstantComposite instruction with the given
287   /// `operands`.
288   LogicalResult processConstantComposite(ArrayRef<uint32_t> operands);
289 
290   /// Processes a SPIR-V OpSpecConstantComposite instruction with the given
291   /// `operands`.
292   LogicalResult processSpecConstantComposite(ArrayRef<uint32_t> operands);
293 
294   /// Processes a SPIR-V OpSpecConstantOp instruction with the given
295   /// `operands`.
296   LogicalResult processSpecConstantOperation(ArrayRef<uint32_t> operands);
297 
298   /// Materializes/emits an OpSpecConstantOp instruction.
299   Value materializeSpecConstantOperation(uint32_t resultID,
300                                          spirv::Opcode enclosedOpcode,
301                                          uint32_t resultTypeID,
302                                          ArrayRef<uint32_t> enclosedOpOperands);
303 
304   /// Processes a SPIR-V OpConstantNull instruction with the given `operands`.
305   LogicalResult processConstantNull(ArrayRef<uint32_t> operands);
306 
307   //===--------------------------------------------------------------------===//
308   // Debug
309   //===--------------------------------------------------------------------===//
310 
311   /// Discontinues any source-level location information that might be active
312   /// from a previous OpLine instruction.
313   void clearDebugLine();
314 
315   /// Creates a FileLineColLoc with the OpLine location information.
316   Location createFileLineColLoc(OpBuilder opBuilder);
317 
318   /// Processes a SPIR-V OpLine instruction with the given `operands`.
319   LogicalResult processDebugLine(ArrayRef<uint32_t> operands);
320 
321   /// Processes a SPIR-V OpString instruction with the given `operands`.
322   LogicalResult processDebugString(ArrayRef<uint32_t> operands);
323 
324   //===--------------------------------------------------------------------===//
325   // Control flow
326   //===--------------------------------------------------------------------===//
327 
328   /// Returns the block for the given label <id>.
getBlock(uint32_t id)329   Block *getBlock(uint32_t id) const { return blockMap.lookup(id); }
330 
331   // In SPIR-V, structured control flow is explicitly declared using merge
332   // instructions (OpSelectionMerge and OpLoopMerge). In the SPIR-V dialect,
333   // we use spv.mlir.selection and spv.mlir.loop to group structured control
334   // flow. The deserializer need to turn structured control flow marked with
335   // merge instructions into using spv.mlir.selection/spv.mlir.loop ops.
336   //
337   // Because structured control flow can nest and the basic block order have
338   // flexibility, we cannot isolate a structured selection/loop without
339   // deserializing all the blocks. So we use the following approach:
340   //
341   // 1. Deserialize all basic blocks in a function and create MLIR blocks for
342   //    them into the function's region. In the meanwhile, keep a map between
343   //    selection/loop header blocks to their corresponding merge (and continue)
344   //    target blocks.
345   // 2. For each selection/loop header block, recursively get all basic blocks
346   //    reachable (except the merge block) and put them in a newly created
347   //    spv.mlir.selection/spv.mlir.loop's region. Structured control flow
348   //    guarantees that we enter and exit in structured ways and the construct
349   //    is nestable.
350   // 3. Put the new spv.mlir.selection/spv.mlir.loop op at the beginning of the
351   //    old merge block and redirect all branches to the old header block to the
352   //    old merge block (which contains the spv.mlir.selection/spv.mlir.loop op
353   //    now).
354 
355   /// For OpPhi instructions, we use block arguments to represent them. OpPhi
356   /// encodes a list of (value, predecessor) pairs. At the time of handling the
357   /// block containing an OpPhi instruction, the predecessor block might not be
358   /// processed yet, also the value sent by it. So we need to defer handling
359   /// the block argument from the predecessors. We use the following approach:
360   ///
361   /// 1. For each OpPhi instruction, add a block argument to the current block
362   ///    in construction. Record the block argument in `valueMap` so its uses
363   ///    can be resolved. For the list of (value, predecessor) pairs, update
364   ///    `blockPhiInfo` for bookkeeping.
365   /// 2. After processing all blocks, loop over `blockPhiInfo` to fix up each
366   ///    block recorded there to create the proper block arguments on their
367   ///    terminators.
368 
369   /// A data structure for containing a SPIR-V block's phi info. It will be
370   /// represented as block argument in SPIR-V dialect.
371   using BlockPhiInfo =
372       SmallVector<uint32_t, 2>; // The result <id> of the values sent
373 
374   /// Gets or creates the block corresponding to the given label <id>. The newly
375   /// created block will always be placed at the end of the current function.
376   Block *getOrCreateBlock(uint32_t id);
377 
378   LogicalResult processBranch(ArrayRef<uint32_t> operands);
379 
380   LogicalResult processBranchConditional(ArrayRef<uint32_t> operands);
381 
382   /// Processes a SPIR-V OpLabel instruction with the given `operands`.
383   LogicalResult processLabel(ArrayRef<uint32_t> operands);
384 
385   /// Processes a SPIR-V OpSelectionMerge instruction with the given `operands`.
386   LogicalResult processSelectionMerge(ArrayRef<uint32_t> operands);
387 
388   /// Processes a SPIR-V OpLoopMerge instruction with the given `operands`.
389   LogicalResult processLoopMerge(ArrayRef<uint32_t> operands);
390 
391   /// Processes a SPIR-V OpPhi instruction with the given `operands`.
392   LogicalResult processPhi(ArrayRef<uint32_t> operands);
393 
394   /// Creates block arguments on predecessors previously recorded when handling
395   /// OpPhi instructions.
396   LogicalResult wireUpBlockArgument();
397 
398   /// Extracts blocks belonging to a structured selection/loop into a
399   /// spv.mlir.selection/spv.mlir.loop op. This method iterates until all blocks
400   /// declared as selection/loop headers are handled.
401   LogicalResult structurizeControlFlow();
402 
403   //===--------------------------------------------------------------------===//
404   // Instruction
405   //===--------------------------------------------------------------------===//
406 
407   /// Get the Value associated with a result <id>.
408   ///
409   /// This method materializes normal constants and inserts "casting" ops
410   /// (`spv.mlir.addressof` and `spv.mlir.referenceof`) to turn an symbol into a
411   /// SSA value for handling uses of module scope constants/variables in
412   /// functions.
413   Value getValue(uint32_t id);
414 
415   /// Slices the first instruction out of `binary` and returns its opcode and
416   /// operands via `opcode` and `operands` respectively. Returns failure if
417   /// there is no more remaining instructions (`expectedOpcode` will be used to
418   /// compose the error message) or the next instruction is malformed.
419   LogicalResult
420   sliceInstruction(spirv::Opcode &opcode, ArrayRef<uint32_t> &operands,
421                    Optional<spirv::Opcode> expectedOpcode = llvm::None);
422 
423   /// Processes a SPIR-V instruction with the given `opcode` and `operands`.
424   /// This method is the main entrance for handling SPIR-V instruction; it
425   /// checks the instruction opcode and dispatches to the corresponding handler.
426   /// Processing of Some instructions (like OpEntryPoint and OpExecutionMode)
427   /// might need to be deferred, since they contain forward references to <id>s
428   /// in the deserialized binary, but module in SPIR-V dialect expects these to
429   /// be ssa-uses.
430   LogicalResult processInstruction(spirv::Opcode opcode,
431                                    ArrayRef<uint32_t> operands,
432                                    bool deferInstructions = true);
433 
434   /// Processes a SPIR-V instruction from the given `operands`. It should
435   /// deserialize into an op with the given `opName` and `numOperands`.
436   /// This method is a generic one for dispatching any SPIR-V ops without
437   /// variadic operands and attributes in TableGen definitions.
438   LogicalResult processOpWithoutGrammarAttr(ArrayRef<uint32_t> words,
439                                             StringRef opName, bool hasResult,
440                                             unsigned numOperands);
441 
442   /// Processes a OpUndef instruction. Adds a spv.Undef operation at the current
443   /// insertion point.
444   LogicalResult processUndef(ArrayRef<uint32_t> operands);
445 
446   /// Method to dispatch to the specialized deserialization function for an
447   /// operation in SPIR-V dialect that is a mirror of an instruction in the
448   /// SPIR-V spec. This is auto-generated from ODS. Dispatch is handled for
449   /// all operations in SPIR-V dialect that have hasOpcode == 1.
450   LogicalResult dispatchToAutogenDeserialization(spirv::Opcode opcode,
451                                                  ArrayRef<uint32_t> words);
452 
453   /// Processes a SPIR-V OpExtInst with given `operands`. This slices the
454   /// entries of `operands` that specify the extended instruction set <id> and
455   /// the instruction opcode. The op deserializer is then invoked using the
456   /// other entries.
457   LogicalResult processExtInst(ArrayRef<uint32_t> operands);
458 
459   /// Dispatches the deserialization of extended instruction set operation based
460   /// on the extended instruction set name, and instruction opcode. This is
461   /// autogenerated from ODS.
462   LogicalResult
463   dispatchToExtensionSetAutogenDeserialization(StringRef extensionSetName,
464                                                uint32_t instructionID,
465                                                ArrayRef<uint32_t> words);
466 
467   /// Method to deserialize an operation in the SPIR-V dialect that is a mirror
468   /// of an instruction in the SPIR-V spec. This is auto generated if hasOpcode
469   /// == 1 and autogenSerialization == 1 in ODS.
470   template <typename OpTy>
processOp(ArrayRef<uint32_t> words)471   LogicalResult processOp(ArrayRef<uint32_t> words) {
472     return emitError(unknownLoc, "unsupported deserialization for ")
473            << OpTy::getOperationName() << " op";
474   }
475 
476 private:
477   /// The SPIR-V binary module.
478   ArrayRef<uint32_t> binary;
479 
480   /// Contains the data of the OpLine instruction which precedes the current
481   /// processing instruction.
482   llvm::Optional<DebugLine> debugLine;
483 
484   /// The current word offset into the binary module.
485   unsigned curOffset = 0;
486 
487   /// MLIRContext to create SPIR-V ModuleOp into.
488   MLIRContext *context;
489 
490   // TODO: create Location subclass for binary blob
491   Location unknownLoc;
492 
493   /// The SPIR-V ModuleOp.
494   OwningOpRef<spirv::ModuleOp> module;
495 
496   /// The current function under construction.
497   Optional<spirv::FuncOp> curFunction;
498 
499   /// The current block under construction.
500   Block *curBlock = nullptr;
501 
502   OpBuilder opBuilder;
503 
504   spirv::Version version = spirv::Version::V_1_0;
505 
506   /// The list of capabilities used by the module.
507   llvm::SmallSetVector<spirv::Capability, 4> capabilities;
508 
509   /// The list of extensions used by the module.
510   llvm::SmallSetVector<spirv::Extension, 2> extensions;
511 
512   // Result <id> to type mapping.
513   DenseMap<uint32_t, Type> typeMap;
514 
515   // Result <id> to constant attribute and type mapping.
516   ///
517   /// In the SPIR-V binary format, all constants are placed in the module and
518   /// shared by instructions at module level and in subsequent functions. But in
519   /// the SPIR-V dialect, we materialize the constant to where it's used in the
520   /// function. So when seeing a constant instruction in the binary format, we
521   /// don't immediately emit a constant op into the module, we keep its value
522   /// (and type) here. Later when it's used, we materialize the constant.
523   DenseMap<uint32_t, std::pair<Attribute, Type>> constantMap;
524 
525   // Result <id> to spec constant mapping.
526   DenseMap<uint32_t, spirv::SpecConstantOp> specConstMap;
527 
528   // Result <id> to composite spec constant mapping.
529   DenseMap<uint32_t, spirv::SpecConstantCompositeOp> specConstCompositeMap;
530 
531   /// Result <id> to info needed to materialize an OpSpecConstantOp
532   /// mapping.
533   DenseMap<uint32_t, SpecConstOperationMaterializationInfo>
534       specConstOperationMap;
535 
536   // Result <id> to variable mapping.
537   DenseMap<uint32_t, spirv::GlobalVariableOp> globalVariableMap;
538 
539   // Result <id> to function mapping.
540   DenseMap<uint32_t, spirv::FuncOp> funcMap;
541 
542   // Result <id> to block mapping.
543   DenseMap<uint32_t, Block *> blockMap;
544 
545   // Header block to its merge (and continue) target mapping.
546   BlockMergeInfoMap blockMergeInfo;
547 
548   // For each pair of {predecessor, target} blocks, maps the pair of blocks to
549   // the list of phi arguments passed from predecessor to target.
550   DenseMap<std::pair<Block * /*predecessor*/, Block * /*target*/>, BlockPhiInfo>
551       blockPhiInfo;
552 
553   // Result <id> to value mapping.
554   DenseMap<uint32_t, Value> valueMap;
555 
556   // Mapping from result <id> to undef value of a type.
557   DenseMap<uint32_t, Type> undefMap;
558 
559   // Result <id> to name mapping.
560   DenseMap<uint32_t, StringRef> nameMap;
561 
562   // Result <id> to debug info mapping.
563   DenseMap<uint32_t, StringRef> debugInfoMap;
564 
565   // Result <id> to decorations mapping.
566   DenseMap<uint32_t, NamedAttrList> decorations;
567 
568   // Result <id> to type decorations.
569   DenseMap<uint32_t, uint32_t> typeDecorations;
570 
571   // Result <id> to member decorations.
572   // decorated-struct-type-<id> ->
573   //    (struct-member-index -> (decoration -> decoration-operands))
574   DenseMap<uint32_t,
575            DenseMap<uint32_t, DenseMap<spirv::Decoration, ArrayRef<uint32_t>>>>
576       memberDecorationMap;
577 
578   // Result <id> to member name.
579   // struct-type-<id> -> (struct-member-index -> name)
580   DenseMap<uint32_t, DenseMap<uint32_t, StringRef>> memberNameMap;
581 
582   // Result <id> to extended instruction set name.
583   DenseMap<uint32_t, StringRef> extendedInstSets;
584 
585   // List of instructions that are processed in a deferred fashion (after an
586   // initial processing of the entire binary). Some operations like
587   // OpEntryPoint, and OpExecutionMode use forward references to function
588   // <id>s. In SPIR-V dialect the corresponding operations (spv.EntryPoint and
589   // spv.ExecutionMode) need these references resolved. So these instructions
590   // are deserialized and stored for processing once the entire binary is
591   // processed.
592   SmallVector<std::pair<spirv::Opcode, ArrayRef<uint32_t>>, 4>
593       deferredInstructions;
594 
595   /// A list of IDs for all types forward-declared through OpTypeForwardPointer
596   /// instructions.
597   SetVector<uint32_t> typeForwardPointerIDs;
598 
599   /// A list of all structs which have unresolved member types.
600   SmallVector<DeferredStructTypeInfo, 0> deferredStructTypesInfos;
601 
602 #ifndef NDEBUG
603   /// A logger used to emit information during the deserialzation process.
604   llvm::ScopedPrinter logger;
605 #endif
606 };
607 
608 } // namespace spirv
609 } // namespace mlir
610 
611 #endif // MLIR_TARGET_SPIRV_DESERIALIZER_H
612