1 // Copyright (c) 2017 Google Inc.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //     http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #ifndef SOURCE_VAL_DECORATION_H_
16 #define SOURCE_VAL_DECORATION_H_
17 
18 #include <cstdint>
19 #include <unordered_map>
20 #include <vector>
21 
22 #include "source/latest_version_spirv_header.h"
23 
24 namespace spvtools {
25 namespace val {
26 
27 // An object of this class represents a specific decoration including its
28 // parameters (if any). Decorations are used by OpDecorate and OpMemberDecorate,
29 // and they describe certain properties that can be assigned to one or several
30 // <id>s.
31 //
32 // A Decoration object contains the decoration type (an enum), associated
33 // literal parameters, and struct member index. If the decoration does not apply
34 // to a struct member, then the index is kInvalidIndex. A Decoration object does
35 // not store the target Id, i.e. the Id to which it applies. It is
36 // possible for the same decoration to be applied to several <id>s (and they
37 // might be assigned using separate SPIR-V instructions, possibly using an
38 // assignment through GroupDecorate).
39 //
40 // Example 1: Decoration for an object<id> with no parameters:
41 // OpDecorate %obj Flat
42 //            dec_type_ = SpvDecorationFlat
43 //              params_ = empty vector
44 // struct_member_index_ = kInvalidMember
45 //
46 // Example 2: Decoration for an object<id> with two parameters:
47 // OpDecorate %obj LinkageAttributes "link" Import
48 //            dec_type_ = SpvDecorationLinkageAttributes
49 //              params_ = vector { link, Import }
50 // struct_member_index_ = kInvalidMember
51 //
52 // Example 3: Decoration for a member of a structure with one parameter:
53 // OpMemberDecorate %struct 2 Offset 2
54 //            dec_type_ = SpvDecorationOffset
55 //              params_ = vector { 2 }
56 // struct_member_index_ = 2
57 //
58 class Decoration {
59  public:
60   enum { kInvalidMember = -1 };
61   Decoration(SpvDecoration t,
62              const std::vector<uint32_t>& parameters = std::vector<uint32_t>(),
63              uint32_t member_index = kInvalidMember)
dec_type_(t)64       : dec_type_(t), params_(parameters), struct_member_index_(member_index) {}
65 
set_struct_member_index(uint32_t index)66   void set_struct_member_index(uint32_t index) { struct_member_index_ = index; }
struct_member_index()67   int struct_member_index() const { return struct_member_index_; }
dec_type()68   SpvDecoration dec_type() const { return dec_type_; }
params()69   std::vector<uint32_t>& params() { return params_; }
params()70   const std::vector<uint32_t>& params() const { return params_; }
71 
72   inline bool operator==(const Decoration& rhs) const {
73     return (dec_type_ == rhs.dec_type_ && params_ == rhs.params_ &&
74             struct_member_index_ == rhs.struct_member_index_);
75   }
76 
77  private:
78   SpvDecoration dec_type_;
79   std::vector<uint32_t> params_;
80 
81   // If the decoration applies to a member of a structure type, then the index
82   // of the member is stored here. Otherwise, this is kInvalidIndex.
83   int struct_member_index_;
84 };
85 
86 }  // namespace val
87 }  // namespace spvtools
88 
89 #endif  // SOURCE_VAL_DECORATION_H_
90