• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // Copyright (c) 2019 Google LLC
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_FUZZ_FUZZER_PASS_DONATE_MODULES_H_
16 #define SOURCE_FUZZ_FUZZER_PASS_DONATE_MODULES_H_
17 
18 #include <vector>
19 
20 #include "source/fuzz/fuzzer_pass.h"
21 #include "source/fuzz/fuzzer_util.h"
22 
23 namespace spvtools {
24 namespace fuzz {
25 
26 // A fuzzer pass that randomly adds code from other SPIR-V modules to the module
27 // being transformed.
28 class FuzzerPassDonateModules : public FuzzerPass {
29  public:
30   FuzzerPassDonateModules(
31       opt::IRContext* ir_context, TransformationContext* transformation_context,
32       FuzzerContext* fuzzer_context,
33       protobufs::TransformationSequence* transformations,
34       const std::vector<fuzzerutil::ModuleSupplier>& donor_suppliers);
35 
36   void Apply() override;
37 
38   // Donates the global declarations and functions of |donor_ir_context| into
39   // the fuzzer pass's IR context.  |make_livesafe| dictates whether the
40   // functions of the donated module will be made livesafe (see
41   // FactFunctionIsLivesafe).
42   void DonateSingleModule(opt::IRContext* donor_ir_context, bool make_livesafe);
43 
44  private:
45   // Adapts a storage class coming from a donor module so that it will work
46   // in a recipient module, e.g. by changing Uniform to Private.
47   static SpvStorageClass AdaptStorageClass(SpvStorageClass donor_storage_class);
48 
49   // Identifies all external instruction set imports in |donor_ir_context| and
50   // populates |original_id_to_donated_id| with a mapping from the donor's id
51   // for such an import to a corresponding import in the recipient.  Aborts if
52   // no such corresponding import is available.
53   void HandleExternalInstructionImports(
54       opt::IRContext* donor_ir_context,
55       std::map<uint32_t, uint32_t>* original_id_to_donated_id);
56 
57   // Considers all types, globals, constants and undefs in |donor_ir_context|.
58   // For each instruction, uses |original_to_donated_id| to map its result id to
59   // either (1) the id of an existing identical instruction in the recipient, or
60   // (2) to a fresh id, in which case the instruction is also added to the
61   // recipient (with any operand ids that it uses being remapped via
62   // |original_id_to_donated_id|).
63   void HandleTypesAndValues(
64       opt::IRContext* donor_ir_context,
65       std::map<uint32_t, uint32_t>* original_id_to_donated_id);
66 
67   // Helper method for HandleTypesAndValues, to handle a single type/value.
68   void HandleTypeOrValue(
69       const opt::Instruction& type_or_value,
70       std::map<uint32_t, uint32_t>* original_id_to_donated_id);
71 
72   // Assumes that |donor_ir_context| does not exhibit recursion.  Considers the
73   // functions in |donor_ir_context|'s call graph in a reverse-topologically-
74   // sorted order (leaves-to-root), adding each function to the recipient
75   // module, rewritten to use fresh ids and using |original_id_to_donated_id| to
76   // remap ids.  The |make_livesafe| argument captures whether the functions in
77   // the module are required to be made livesafe before being added to the
78   // recipient.
79   void HandleFunctions(opt::IRContext* donor_ir_context,
80                        std::map<uint32_t, uint32_t>* original_id_to_donated_id,
81                        bool make_livesafe);
82 
83   // During donation we will have to ignore some instructions, e.g. because they
84   // use opcodes that we cannot support or because they reference the ids of
85   // instructions that have not been donated.  This function encapsulates the
86   // logic for deciding which whether instruction |instruction| from
87   // |donor_ir_context| can be donated.
88   bool CanDonateInstruction(
89       opt::IRContext* donor_ir_context, const opt::Instruction& instruction,
90       const std::map<uint32_t, uint32_t>& original_id_to_donated_id,
91       const std::set<uint32_t>& skipped_instructions) const;
92 
93   // We treat the OpArrayLength instruction specially.  In the donor shader this
94   // instruction yields the length of a runtime array that is the final member
95   // of a struct.  During donation, we will have converted the runtime array
96   // type, and the associated struct field, into a fixed-size array.
97   //
98   // Instead of donating this instruction, we turn it into an OpCopyObject
99   // instruction that copies the size of the fixed-size array.
100   void HandleOpArrayLength(
101       const opt::Instruction& instruction,
102       std::map<uint32_t, uint32_t>* original_id_to_donated_id,
103       std::vector<protobufs::Instruction>* donated_instructions) const;
104 
105   // The instruction |instruction| is required to be an instruction that cannot
106   // be easily donated, either because it uses an unsupported opcode, has an
107   // unsupported result type, or uses id operands that could not be donated.
108   //
109   // If |instruction| generates a result id, the function attempts to add a
110   // substitute for |instruction| to |donated_instructions| that has the correct
111   // result type.  If this cannot be done, the instruction's result id is added
112   // to |skipped_instructions|.  The mapping from donor ids to recipient ids is
113   // managed by |original_id_to_donated_id|.
114   void HandleDifficultInstruction(
115       const opt::Instruction& instruction,
116       std::map<uint32_t, uint32_t>* original_id_to_donated_id,
117       std::vector<protobufs::Instruction>* donated_instructions,
118       std::set<uint32_t>* skipped_instructions);
119 
120   // Adds an instruction based in |instruction| to |donated_instructions| in a
121   // form ready for donation.  The original instruction comes from
122   // |donor_ir_context|, and |original_id_to_donated_id| maps ids from
123   // |donor_ir_context| to corresponding ids in the recipient module.
124   void PrepareInstructionForDonation(
125       const opt::Instruction& instruction, opt::IRContext* donor_ir_context,
126       std::map<uint32_t, uint32_t>* original_id_to_donated_id,
127       std::vector<protobufs::Instruction>* donated_instructions);
128 
129   // Tries to create a protobufs::LoopLimiterInfo given a loop header basic
130   // block. Returns true if successful and outputs loop limiter into the |out|
131   // variable. Otherwise, returns false. |out| contains an undefined value when
132   // this function returns false.
133   bool CreateLoopLimiterInfo(
134       opt::IRContext* donor_ir_context, const opt::BasicBlock& loop_header,
135       const std::map<uint32_t, uint32_t>& original_id_to_donated_id,
136       protobufs::LoopLimiterInfo* out);
137 
138   // Requires that |donated_instructions| represents a prepared version of the
139   // instructions of |function_to_donate| (which comes from |donor_ir_context|)
140   // ready for donation, and |original_id_to_donated_id| maps ids from
141   // |donor_ir_context| to their corresponding ids in the recipient module.
142   //
143   // Attempts to add a livesafe version of the function, based on
144   // |donated_instructions|, to the recipient module. Returns true if the
145   // donation was successful, false otherwise.
146   bool MaybeAddLivesafeFunction(
147       const opt::Function& function_to_donate, opt::IRContext* donor_ir_context,
148       const std::map<uint32_t, uint32_t>& original_id_to_donated_id,
149       const std::vector<protobufs::Instruction>& donated_instructions);
150 
151   // Returns true if and only if |instruction| is a scalar, vector, matrix,
152   // array or struct; i.e. it is not an opaque type.
153   bool IsBasicType(const opt::Instruction& instruction) const;
154 
155   // Functions that supply SPIR-V modules
156   std::vector<fuzzerutil::ModuleSupplier> donor_suppliers_;
157 };
158 
159 }  // namespace fuzz
160 }  // namespace spvtools
161 
162 #endif  // SOURCE_FUZZ_FUZZER_PASS_DONATE_MODULES_H_
163