source/fuzz/transformation_expand_vector_reduction.cpp

   1 // Copyright (c) 2020 André Perez Maselco
   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 #include "source/fuzz/transformation_expand_vector_reduction.h"
  16
  17 #include "source/fuzz/fuzzer_util.h"
  18 #include "source/fuzz/instruction_descriptor.h"
  19
  20 namespace spvtools {
  21 namespace fuzz {
  22
  23 TransformationExpandVectorReduction::TransformationExpandVectorReduction(
  24     protobufs::TransformationExpandVectorReduction message)
  25     : message_(std::move(message)) {}
  26
  27 TransformationExpandVectorReduction::TransformationExpandVectorReduction(
  28     const uint32_t instruction_result_id,
  29     const std::vector<uint32_t>& fresh_ids) {
  30   message_.set_instruction_result_id(instruction_result_id);
  31   *message_.mutable_fresh_ids() =
  32       google::protobuf::RepeatedField<google::protobuf::uint32>(
  33           fresh_ids.begin(), fresh_ids.end());
  34 }
  35
  36 bool TransformationExpandVectorReduction::IsApplicable(
  37     opt::IRContext* ir_context, const TransformationContext& /*unused*/) const {
  38   auto* instruction =
  39       ir_context->get_def_use_mgr()->GetDef(message_.instruction_result_id());
  40
  41   // |instruction| must be defined.
  42   if (!instruction) {
  43     return false;
  44   }
  45
  46   // |instruction| must be OpAny or OpAll.
  47   if (instruction->opcode() != spv::Op::OpAny &&
  48       instruction->opcode() != spv::Op::OpAll) {
  49     return false;
  50   }
  51
  52   // |message_.fresh_ids.size| must have the exact number of fresh ids required
  53   // to apply the transformation.
  54   if (static_cast<uint32_t>(message_.fresh_ids().size()) !=
  55       GetRequiredFreshIdCount(ir_context, instruction)) {
  56     return false;
  57   }
  58
  59   std::set<uint32_t> ids_used_by_this_transformation;
  60   for (uint32_t fresh_id : message_.fresh_ids()) {
  61     // All ids in |message_.fresh_ids| must be fresh.
  62     if (!fuzzerutil::IsFreshId(ir_context, fresh_id)) {
  63       return false;
  64     }
  65
  66     // All fresh ids need to be distinct.
  67     if (!CheckIdIsFreshAndNotUsedByThisTransformation(
  68             fresh_id, ir_context, &ids_used_by_this_transformation)) {
  69       return false;
  70     }
  71   }
  72
  73   return true;
  74 }
  75
  76 void TransformationExpandVectorReduction::Apply(
  77     opt::IRContext* ir_context,
  78     TransformationContext* transformation_context) const {
  79   auto* instruction =
  80       ir_context->get_def_use_mgr()->GetDef(message_.instruction_result_id());
  81   auto* vector = ir_context->get_def_use_mgr()->GetDef(
  82       instruction->GetSingleWordInOperand(0));
  83   uint32_t vector_component_count = ir_context->get_type_mgr()
  84                                         ->GetType(vector->type_id())
  85                                         ->AsVector()
  86                                         ->element_count();
  87
  88   // Fresh id iterator.
  89   auto fresh_id = message_.fresh_ids().begin();
  90
  91   // |vector_components| are the ids of the extracted components from |vector|.
  92   std::vector<uint32_t> vector_components;
  93
  94   for (uint32_t i = 0; i < vector_component_count; i++) {
  95     // Extracts the i-th |vector| component.
  96     auto vector_component =
  97         opt::Instruction(ir_context, spv::Op::OpCompositeExtract,
  98                          instruction->type_id(), *fresh_id++,
  99                          {{SPV_OPERAND_TYPE_ID, {vector->result_id()}},
 100                           {SPV_OPERAND_TYPE_LITERAL_INTEGER, {i}}});
 101     instruction->InsertBefore(MakeUnique<opt::Instruction>(vector_component));
 102     fuzzerutil::UpdateModuleIdBound(ir_context, vector_component.result_id());
 103     vector_components.push_back(vector_component.result_id());
 104   }
 105
 106   // The first two |vector| components are used in the first logical operation.
 107   auto logical_instruction = opt::Instruction(
 108       ir_context,
 109       instruction->opcode() == spv::Op::OpAny ? spv::Op::OpLogicalOr
 110                                               : spv::Op::OpLogicalAnd,
 111       instruction->type_id(), *fresh_id++,
 112       {{SPV_OPERAND_TYPE_ID, {vector_components[0]}},
 113        {SPV_OPERAND_TYPE_ID, {vector_components[1]}}});
 114   instruction->InsertBefore(MakeUnique<opt::Instruction>(logical_instruction));
 115   fuzzerutil::UpdateModuleIdBound(ir_context, logical_instruction.result_id());
 116
 117   // Evaluates the remaining components.
 118   for (uint32_t i = 2; i < vector_components.size(); i++) {
 119     logical_instruction = opt::Instruction(
 120         ir_context, logical_instruction.opcode(), instruction->type_id(),
 121         *fresh_id++,
 122         {{SPV_OPERAND_TYPE_ID, {vector_components[i]}},
 123          {SPV_OPERAND_TYPE_ID, {logical_instruction.result_id()}}});
 124     instruction->InsertBefore(
 125         MakeUnique<opt::Instruction>(logical_instruction));
 126     fuzzerutil::UpdateModuleIdBound(ir_context,
 127                                     logical_instruction.result_id());
 128   }
 129
 130   ir_context->InvalidateAnalysesExceptFor(opt::IRContext::kAnalysisNone);
 131
 132   // If it's possible to make a synonym of |instruction|, then add the fact that
 133   // the last |logical_instruction| is a synonym of |instruction|.
 134   if (fuzzerutil::CanMakeSynonymOf(ir_context, *transformation_context,
 135                                    *instruction)) {
 136     transformation_context->GetFactManager()->AddFactDataSynonym(
 137         MakeDataDescriptor(logical_instruction.result_id(), {}),
 138         MakeDataDescriptor(instruction->result_id(), {}));
 139   }
 140 }
 141
 142 protobufs::Transformation TransformationExpandVectorReduction::ToMessage()
 143     const {
 144   protobufs::Transformation result;
 145   *result.mutable_expand_vector_reduction() = message_;
 146   return result;
 147 }
 148
 149 uint32_t TransformationExpandVectorReduction::GetRequiredFreshIdCount(
 150     opt::IRContext* ir_context, opt::Instruction* instruction) {
 151   // For each vector component, 1 OpCompositeExtract and 1 OpLogical* (except
 152   // for the first component) instructions will be inserted.
 153   return 2 * ir_context->get_type_mgr()
 154                  ->GetType(ir_context->get_def_use_mgr()
 155                                ->GetDef(instruction->GetSingleWordInOperand(0))
 156                                ->type_id())
 157                  ->AsVector()
 158                  ->element_count() -
 159          1;
 160 }
 161
 162 std::unordered_set<uint32_t> TransformationExpandVectorReduction::GetFreshIds()
 163     const {
 164   std::unordered_set<uint32_t> result;
 165   for (auto id : message_.fresh_ids()) {
 166     result.insert(id);
 167   }
 168   return result;
 169 }
 170
 171 }  // namespace fuzz
 172 }  // namespace spvtools