SPIRV-Tools/source/fuzz/transformation_composite_insert.cpp
Alastair Donaldson 11cd875ed8
spirv-fuzz: Use reference in CanMakeSynonymOf (#4401)
The instruction parameter of CanMakeSynonymOf is an input parameter
that should never be null, so a const reference is a more appropriate
type than a const pointer.
2021-07-27 13:18:36 +01:00

247 lines
9.3 KiB
C++

// Copyright (c) 2020 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "transformation_composite_insert.h"
#include "source/fuzz/fuzzer_util.h"
#include "source/fuzz/instruction_descriptor.h"
namespace spvtools {
namespace fuzz {
TransformationCompositeInsert::TransformationCompositeInsert(
protobufs::TransformationCompositeInsert message)
: message_(std::move(message)) {}
TransformationCompositeInsert::TransformationCompositeInsert(
const protobufs::InstructionDescriptor& instruction_to_insert_before,
uint32_t fresh_id, uint32_t composite_id, uint32_t object_id,
const std::vector<uint32_t>& index) {
*message_.mutable_instruction_to_insert_before() =
instruction_to_insert_before;
message_.set_fresh_id(fresh_id);
message_.set_composite_id(composite_id);
message_.set_object_id(object_id);
for (auto an_index : index) {
message_.add_index(an_index);
}
}
bool TransformationCompositeInsert::IsApplicable(
opt::IRContext* ir_context, const TransformationContext& /*unused*/) const {
// |message_.fresh_id| must be fresh.
if (!fuzzerutil::IsFreshId(ir_context, message_.fresh_id())) {
return false;
}
// |message_.composite_id| must refer to an existing composite value.
auto composite =
ir_context->get_def_use_mgr()->GetDef(message_.composite_id());
if (!IsCompositeInstructionSupported(ir_context, composite)) {
return false;
}
// The indices in |message_.index| must be suitable for indexing into
// |composite->type_id()|.
auto component_to_be_replaced_type_id = fuzzerutil::WalkCompositeTypeIndices(
ir_context, composite->type_id(), message_.index());
if (component_to_be_replaced_type_id == 0) {
return false;
}
// The instruction having the id of |message_.object_id| must be defined.
auto object_instruction =
ir_context->get_def_use_mgr()->GetDef(message_.object_id());
if (object_instruction == nullptr || object_instruction->type_id() == 0) {
return false;
}
// We ignore pointers for now.
auto object_instruction_type =
ir_context->get_type_mgr()->GetType(object_instruction->type_id());
if (object_instruction_type->AsPointer() != nullptr) {
return false;
}
// The type id of the object having |message_.object_id| and the type id of
// the component of the composite at index |message_.index| must be the same.
if (component_to_be_replaced_type_id != object_instruction->type_id()) {
return false;
}
// |message_.instruction_to_insert_before| must be a defined instruction.
auto instruction_to_insert_before =
FindInstruction(message_.instruction_to_insert_before(), ir_context);
if (instruction_to_insert_before == nullptr) {
return false;
}
// |message_.composite_id| and |message_.object_id| must be available before
// the |message_.instruction_to_insert_before|.
if (!fuzzerutil::IdIsAvailableBeforeInstruction(
ir_context, instruction_to_insert_before, message_.composite_id())) {
return false;
}
if (!fuzzerutil::IdIsAvailableBeforeInstruction(
ir_context, instruction_to_insert_before, message_.object_id())) {
return false;
}
// It must be possible to insert an OpCompositeInsert before this
// instruction.
return fuzzerutil::CanInsertOpcodeBeforeInstruction(
SpvOpCompositeInsert, instruction_to_insert_before);
}
void TransformationCompositeInsert::Apply(
opt::IRContext* ir_context,
TransformationContext* transformation_context) const {
// |message_.struct_fresh_id| must be fresh.
assert(fuzzerutil::IsFreshId(ir_context, message_.fresh_id()) &&
"|message_.fresh_id| must be fresh");
std::vector<uint32_t> index =
fuzzerutil::RepeatedFieldToVector(message_.index());
opt::Instruction::OperandList in_operands;
in_operands.push_back({SPV_OPERAND_TYPE_ID, {message_.object_id()}});
in_operands.push_back({SPV_OPERAND_TYPE_ID, {message_.composite_id()}});
for (auto i : index) {
in_operands.push_back({SPV_OPERAND_TYPE_LITERAL_INTEGER, {i}});
}
auto composite_type_id =
fuzzerutil::GetTypeId(ir_context, message_.composite_id());
auto insert_before =
FindInstruction(message_.instruction_to_insert_before(), ir_context);
auto new_instruction = MakeUnique<opt::Instruction>(
ir_context, SpvOpCompositeInsert, composite_type_id, message_.fresh_id(),
std::move(in_operands));
auto new_instruction_ptr = new_instruction.get();
insert_before->InsertBefore(std::move(new_instruction));
fuzzerutil::UpdateModuleIdBound(ir_context, message_.fresh_id());
// Inform the def-use manager about the new instruction and record its basic
// block.
ir_context->get_def_use_mgr()->AnalyzeInstDefUse(new_instruction_ptr);
ir_context->set_instr_block(new_instruction_ptr,
ir_context->get_instr_block(insert_before));
// Add data synonym facts that arise from the insertion.
AddDataSynonymFacts(ir_context, transformation_context);
}
protobufs::Transformation TransformationCompositeInsert::ToMessage() const {
protobufs::Transformation result;
*result.mutable_composite_insert() = message_;
return result;
}
bool TransformationCompositeInsert::IsCompositeInstructionSupported(
opt::IRContext* ir_context, opt::Instruction* instruction) {
if (instruction == nullptr) {
return false;
}
if (instruction->result_id() == 0 || instruction->type_id() == 0) {
return false;
}
auto composite_type =
ir_context->get_type_mgr()->GetType(instruction->type_id());
if (!fuzzerutil::IsCompositeType(composite_type)) {
return false;
}
// Empty composites are not supported.
auto instruction_type_inst =
ir_context->get_def_use_mgr()->GetDef(instruction->type_id());
if (fuzzerutil::GetBoundForCompositeIndex(*instruction_type_inst,
ir_context) == 0) {
return false;
}
return true;
}
std::unordered_set<uint32_t> TransformationCompositeInsert::GetFreshIds()
const {
return {message_.fresh_id()};
}
void TransformationCompositeInsert::AddDataSynonymFacts(
opt::IRContext* ir_context,
TransformationContext* transformation_context) const {
// If the result id arising from the insertion is irrelevant then do not add
// any data synonym facts. (The result id can be irrelevant if the insertion
// occurs in a dead block.)
if (transformation_context->GetFactManager()->IdIsIrrelevant(
message_.fresh_id())) {
return;
}
// So long as the |message_.composite_id| is suitable for participating in
// synonyms, every every element of the insertion result except for at the
// index being inserted into is synonymous with the corresponding element of
// |message_.composite_id|. In that case, for every index that is a prefix of
// |index|, the components different from the one that contains the inserted
// object are synonymous with corresponding elements in the original
// composite.
uint32_t current_node_type_id =
fuzzerutil::GetTypeId(ir_context, message_.composite_id());
std::vector<uint32_t> current_index;
std::vector<uint32_t> index =
fuzzerutil::RepeatedFieldToVector(message_.index());
for (uint32_t current_level : index) {
auto current_node_type_inst =
ir_context->get_def_use_mgr()->GetDef(current_node_type_id);
uint32_t index_to_skip = current_level;
uint32_t num_of_components = fuzzerutil::GetBoundForCompositeIndex(
*current_node_type_inst, ir_context);
// Update the current_node_type_id.
current_node_type_id = fuzzerutil::WalkOneCompositeTypeIndex(
ir_context, current_node_type_id, index_to_skip);
for (uint32_t i = 0; i < num_of_components; i++) {
if (i == index_to_skip) {
continue;
}
current_index.push_back(i);
if (fuzzerutil::CanMakeSynonymOf(ir_context, *transformation_context,
*ir_context->get_def_use_mgr()->GetDef(
message_.composite_id()))) {
transformation_context->GetFactManager()->AddFactDataSynonym(
MakeDataDescriptor(message_.fresh_id(), current_index),
MakeDataDescriptor(message_.composite_id(), current_index));
}
current_index.pop_back();
}
// Store the prefix of the |index|.
current_index.push_back(current_level);
}
// If the object being inserted supports synonym creation then it is
// synonymous with the result of the insert instruction at the given index.
if (fuzzerutil::CanMakeSynonymOf(
ir_context, *transformation_context,
*ir_context->get_def_use_mgr()->GetDef(message_.object_id()))) {
transformation_context->GetFactManager()->AddFactDataSynonym(
MakeDataDescriptor(message_.object_id(), {}),
MakeDataDescriptor(message_.fresh_id(), index));
}
}
} // namespace fuzz
} // namespace spvtools