| 1 | //===- VarLenCodeEmitterGen.h - CEG for variable-length insts ---*- C++ -*-===// |
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| 2 | // |
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| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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| 4 | // See https://llvm.org/LICENSE.txt for license information. |
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| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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| 6 | // |
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| 7 | //===----------------------------------------------------------------------===// |
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| 8 | // |
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| 9 | // This file declare the CodeEmitterGen component for variable-length |
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| 10 | // instructions. See the .cpp file for more details. |
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| 11 | // |
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| 12 | //===----------------------------------------------------------------------===// |
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| 13 | |
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| 14 | #ifndef LLVM_UTILS_TABLEGEN_VARLENCODEEMITTERGEN_H |
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| 15 | #define LLVM_UTILS_TABLEGEN_VARLENCODEEMITTERGEN_H |
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| 16 | |
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| 17 | #include "llvm/TableGen/Record.h" |
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| 18 | |
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| 19 | namespace llvm { |
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| 20 | |
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| 21 | struct EncodingSegment { |
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| 22 | unsigned BitWidth; |
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| 23 | const Init *Value; |
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| 24 | StringRef CustomEncoder = "" ; |
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| 25 | StringRef CustomDecoder = "" ; |
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| 26 | }; |
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| 27 | |
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| 28 | class VarLenInst { |
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| 29 | const RecordVal *TheDef; |
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| 30 | size_t NumBits; |
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| 31 | |
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| 32 | // Set if any of the segment is not fixed value. |
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| 33 | bool HasDynamicSegment; |
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| 34 | |
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| 35 | SmallVector<EncodingSegment, 4> Segments; |
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| 36 | |
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| 37 | void buildRec(const DagInit *DI); |
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| 38 | |
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| 39 | public: |
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| 40 | VarLenInst() : TheDef(nullptr), NumBits(0U), HasDynamicSegment(false) {} |
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| 41 | |
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| 42 | explicit VarLenInst(const DagInit *DI, const RecordVal *TheDef); |
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| 43 | |
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| 44 | /// Number of bits |
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| 45 | size_t size() const { return NumBits; } |
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| 46 | |
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| 47 | using const_iterator = decltype(Segments)::const_iterator; |
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| 48 | |
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| 49 | const_iterator begin() const { return Segments.begin(); } |
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| 50 | const_iterator end() const { return Segments.end(); } |
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| 51 | size_t getNumSegments() const { return Segments.size(); } |
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| 52 | |
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| 53 | bool isFixedValueOnly() const { return !HasDynamicSegment; } |
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| 54 | }; |
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| 55 | |
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| 56 | void emitVarLenCodeEmitter(RecordKeeper &R, raw_ostream &OS); |
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| 57 | |
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| 58 | } // end namespace llvm |
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| 59 | #endif |
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| 60 | |
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