SPIRV-Tools/source/fuzz/transformation_composite_construct.cpp
2020-10-08 22:34:39 +01:00

323 lines
12 KiB
C++

// Copyright (c) 2019 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 "source/fuzz/transformation_composite_construct.h"
#include "source/fuzz/data_descriptor.h"
#include "source/fuzz/fuzzer_util.h"
#include "source/fuzz/instruction_descriptor.h"
#include "source/opt/instruction.h"
namespace spvtools {
namespace fuzz {
TransformationCompositeConstruct::TransformationCompositeConstruct(
const protobufs::TransformationCompositeConstruct& message)
: message_(message) {}
TransformationCompositeConstruct::TransformationCompositeConstruct(
uint32_t composite_type_id, std::vector<uint32_t> component,
const protobufs::InstructionDescriptor& instruction_to_insert_before,
uint32_t fresh_id) {
message_.set_composite_type_id(composite_type_id);
for (auto a_component : component) {
message_.add_component(a_component);
}
*message_.mutable_instruction_to_insert_before() =
instruction_to_insert_before;
message_.set_fresh_id(fresh_id);
}
bool TransformationCompositeConstruct::IsApplicable(
opt::IRContext* ir_context, const TransformationContext& /*unused*/) const {
if (!fuzzerutil::IsFreshId(ir_context, message_.fresh_id())) {
// We require the id for the composite constructor to be unused.
return false;
}
auto insert_before =
FindInstruction(message_.instruction_to_insert_before(), ir_context);
if (!insert_before) {
// The instruction before which the composite should be inserted was not
// found.
return false;
}
auto composite_type =
ir_context->get_type_mgr()->GetType(message_.composite_type_id());
if (!fuzzerutil::IsCompositeType(composite_type)) {
// The type must actually be a composite.
return false;
}
// If the type is an array, matrix, struct or vector, the components need to
// be suitable for constructing something of that type.
if (composite_type->AsArray() &&
!ComponentsForArrayConstructionAreOK(ir_context,
*composite_type->AsArray())) {
return false;
}
if (composite_type->AsMatrix() &&
!ComponentsForMatrixConstructionAreOK(ir_context,
*composite_type->AsMatrix())) {
return false;
}
if (composite_type->AsStruct() &&
!ComponentsForStructConstructionAreOK(ir_context,
*composite_type->AsStruct())) {
return false;
}
if (composite_type->AsVector() &&
!ComponentsForVectorConstructionAreOK(ir_context,
*composite_type->AsVector())) {
return false;
}
// Now check whether every component being used to initialize the composite is
// available at the desired program point.
for (auto component : message_.component()) {
auto* inst = ir_context->get_def_use_mgr()->GetDef(component);
if (!inst) {
return false;
}
if (!fuzzerutil::IdIsAvailableBeforeInstruction(ir_context, insert_before,
component)) {
return false;
}
}
return true;
}
void TransformationCompositeConstruct::Apply(
opt::IRContext* ir_context,
TransformationContext* transformation_context) const {
// Use the base and offset information from the transformation to determine
// where in the module a new instruction should be inserted.
auto insert_before_inst =
FindInstruction(message_.instruction_to_insert_before(), ir_context);
auto destination_block = ir_context->get_instr_block(insert_before_inst);
auto insert_before = fuzzerutil::GetIteratorForInstruction(
destination_block, insert_before_inst);
// Prepare the input operands for an OpCompositeConstruct instruction.
opt::Instruction::OperandList in_operands;
for (auto& component_id : message_.component()) {
in_operands.push_back({SPV_OPERAND_TYPE_ID, {component_id}});
}
// Insert an OpCompositeConstruct instruction.
insert_before.InsertBefore(MakeUnique<opt::Instruction>(
ir_context, SpvOpCompositeConstruct, message_.composite_type_id(),
message_.fresh_id(), in_operands));
fuzzerutil::UpdateModuleIdBound(ir_context, message_.fresh_id());
ir_context->InvalidateAnalysesExceptFor(opt::IRContext::kAnalysisNone);
AddDataSynonymFacts(ir_context, transformation_context);
}
bool TransformationCompositeConstruct::ComponentsForArrayConstructionAreOK(
opt::IRContext* ir_context, const opt::analysis::Array& array_type) const {
if (array_type.length_info().words[0] !=
opt::analysis::Array::LengthInfo::kConstant) {
// We only handle constant-sized arrays.
return false;
}
if (array_type.length_info().words.size() != 2) {
// We only handle the case where the array size can be captured in a single
// word.
return false;
}
// Get the array size.
auto array_size = array_type.length_info().words[1];
if (static_cast<uint32_t>(message_.component().size()) != array_size) {
// The number of components must match the array size.
return false;
}
// Check that each component is the result id of an instruction whose type is
// the array's element type.
for (auto component_id : message_.component()) {
auto inst = ir_context->get_def_use_mgr()->GetDef(component_id);
if (inst == nullptr || !inst->type_id()) {
// The component does not correspond to an instruction with a result
// type.
return false;
}
auto component_type = ir_context->get_type_mgr()->GetType(inst->type_id());
assert(component_type);
if (component_type != array_type.element_type()) {
// The component's type does not match the array's element type.
return false;
}
}
return true;
}
bool TransformationCompositeConstruct::ComponentsForMatrixConstructionAreOK(
opt::IRContext* ir_context,
const opt::analysis::Matrix& matrix_type) const {
if (static_cast<uint32_t>(message_.component().size()) !=
matrix_type.element_count()) {
// The number of components must match the number of columns of the matrix.
return false;
}
// Check that each component is the result id of an instruction whose type is
// the matrix's column type.
for (auto component_id : message_.component()) {
auto inst = ir_context->get_def_use_mgr()->GetDef(component_id);
if (inst == nullptr || !inst->type_id()) {
// The component does not correspond to an instruction with a result
// type.
return false;
}
auto component_type = ir_context->get_type_mgr()->GetType(inst->type_id());
assert(component_type);
if (component_type != matrix_type.element_type()) {
// The component's type does not match the matrix's column type.
return false;
}
}
return true;
}
bool TransformationCompositeConstruct::ComponentsForStructConstructionAreOK(
opt::IRContext* ir_context,
const opt::analysis::Struct& struct_type) const {
if (static_cast<uint32_t>(message_.component().size()) !=
struct_type.element_types().size()) {
// The number of components must match the number of fields of the struct.
return false;
}
// Check that each component is the result id of an instruction those type
// matches the associated field type.
for (uint32_t field_index = 0;
field_index < struct_type.element_types().size(); field_index++) {
auto inst = ir_context->get_def_use_mgr()->GetDef(
message_.component()[field_index]);
if (inst == nullptr || !inst->type_id()) {
// The component does not correspond to an instruction with a result
// type.
return false;
}
auto component_type = ir_context->get_type_mgr()->GetType(inst->type_id());
assert(component_type);
if (component_type != struct_type.element_types()[field_index]) {
// The component's type does not match the corresponding field type.
return false;
}
}
return true;
}
bool TransformationCompositeConstruct::ComponentsForVectorConstructionAreOK(
opt::IRContext* ir_context,
const opt::analysis::Vector& vector_type) const {
uint32_t base_element_count = 0;
auto element_type = vector_type.element_type();
for (auto& component_id : message_.component()) {
auto inst = ir_context->get_def_use_mgr()->GetDef(component_id);
if (inst == nullptr || !inst->type_id()) {
// The component does not correspond to an instruction with a result
// type.
return false;
}
auto component_type = ir_context->get_type_mgr()->GetType(inst->type_id());
assert(component_type);
if (component_type == element_type) {
base_element_count++;
} else if (component_type->AsVector() &&
component_type->AsVector()->element_type() == element_type) {
base_element_count += component_type->AsVector()->element_count();
} else {
// The component was not appropriate; e.g. no type corresponding to the
// given id was found, or the type that was found was not compatible
// with the vector being constructed.
return false;
}
}
// The number of components provided (when vector components are flattened
// out) needs to match the length of the vector being constructed.
return base_element_count == vector_type.element_count();
}
protobufs::Transformation TransformationCompositeConstruct::ToMessage() const {
protobufs::Transformation result;
*result.mutable_composite_construct() = message_;
return result;
}
std::unordered_set<uint32_t> TransformationCompositeConstruct::GetFreshIds()
const {
return {message_.fresh_id()};
}
void TransformationCompositeConstruct::AddDataSynonymFacts(
opt::IRContext* ir_context,
TransformationContext* transformation_context) const {
// If the result id of the composite we are constructing is irrelevant (e.g.
// because it is in a dead block) then we do not make any synonyms.
if (transformation_context->GetFactManager()->IdIsIrrelevant(
message_.fresh_id())) {
return;
}
// Inform the fact manager that we now have new synonyms: every component of
// the composite is synonymous with the id used to construct that component
// (so long as it is legitimate to create a synonym from that id), except in
// the case of a vector where a single vector id can span multiple components.
auto composite_type =
ir_context->get_type_mgr()->GetType(message_.composite_type_id());
uint32_t index = 0;
for (auto component : message_.component()) {
if (!fuzzerutil::CanMakeSynonymOf(
ir_context, *transformation_context,
ir_context->get_def_use_mgr()->GetDef(component))) {
continue;
}
auto component_type = ir_context->get_type_mgr()->GetType(
ir_context->get_def_use_mgr()->GetDef(component)->type_id());
if (composite_type->AsVector() && component_type->AsVector()) {
// The case where the composite being constructed is a vector and the
// component provided for construction is also a vector is special. It
// requires adding a synonym fact relating each element of the sub-vector
// to the corresponding element of the composite being constructed.
assert(component_type->AsVector()->element_type() ==
composite_type->AsVector()->element_type());
assert(component_type->AsVector()->element_count() <
composite_type->AsVector()->element_count());
for (uint32_t subvector_index = 0;
subvector_index < component_type->AsVector()->element_count();
subvector_index++) {
transformation_context->GetFactManager()->AddFactDataSynonym(
MakeDataDescriptor(component, {subvector_index}),
MakeDataDescriptor(message_.fresh_id(), {index}));
index++;
}
} else {
// The other cases are simple: the component is made directly synonymous
// with the element of the composite being constructed.
transformation_context->GetFactManager()->AddFactDataSynonym(
MakeDataDescriptor(component, {}),
MakeDataDescriptor(message_.fresh_id(), {index}));
index++;
}
}
}
} // namespace fuzz
} // namespace spvtools