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

174 lines
7.1 KiB
C++

// Copyright (c) 2020 André Perez Maselco
//
// 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_push_id_through_variable.h"
#include "source/fuzz/fuzzer_util.h"
#include "source/fuzz/instruction_descriptor.h"
namespace spvtools {
namespace fuzz {
TransformationPushIdThroughVariable::TransformationPushIdThroughVariable(
const spvtools::fuzz::protobufs::TransformationPushIdThroughVariable&
message)
: message_(message) {}
TransformationPushIdThroughVariable::TransformationPushIdThroughVariable(
uint32_t value_id, uint32_t value_synonym_id, uint32_t variable_id,
uint32_t variable_storage_class, uint32_t initializer_id,
const protobufs::InstructionDescriptor& instruction_descriptor) {
message_.set_value_id(value_id);
message_.set_value_synonym_id(value_synonym_id);
message_.set_variable_id(variable_id);
message_.set_variable_storage_class(variable_storage_class);
message_.set_initializer_id(initializer_id);
*message_.mutable_instruction_descriptor() = instruction_descriptor;
}
bool TransformationPushIdThroughVariable::IsApplicable(
opt::IRContext* ir_context, const TransformationContext& /*unused*/) const {
// |message_.value_synonym_id| and |message_.variable_id| must be fresh.
if (!fuzzerutil::IsFreshId(ir_context, message_.value_synonym_id()) ||
!fuzzerutil::IsFreshId(ir_context, message_.variable_id())) {
return false;
}
// The instruction to insert before must be defined.
auto instruction_to_insert_before =
FindInstruction(message_.instruction_descriptor(), ir_context);
if (!instruction_to_insert_before) {
return false;
}
// It must be valid to insert the OpStore and OpLoad instruction before it.
if (!fuzzerutil::CanInsertOpcodeBeforeInstruction(
SpvOpStore, instruction_to_insert_before) ||
!fuzzerutil::CanInsertOpcodeBeforeInstruction(
SpvOpLoad, instruction_to_insert_before)) {
return false;
}
// The instruction to insert before must belong to a reachable block.
auto basic_block = ir_context->get_instr_block(instruction_to_insert_before);
if (!fuzzerutil::BlockIsReachableInItsFunction(ir_context, basic_block)) {
return false;
}
// The value instruction must be defined and have a type.
auto value_instruction =
ir_context->get_def_use_mgr()->GetDef(message_.value_id());
if (!value_instruction || !value_instruction->type_id()) {
return false;
}
// A pointer type instruction pointing to the value type must be defined.
auto pointer_type_id = fuzzerutil::MaybeGetPointerType(
ir_context, value_instruction->type_id(),
static_cast<SpvStorageClass>(message_.variable_storage_class()));
if (!pointer_type_id) {
return false;
}
// |message_.variable_storage_class| must be private or function.
assert((message_.variable_storage_class() == SpvStorageClassPrivate ||
message_.variable_storage_class() == SpvStorageClassFunction) &&
"The variable storage class must be private or function.");
// Check that initializer is valid.
const auto* constant_inst =
ir_context->get_def_use_mgr()->GetDef(message_.initializer_id());
if (!constant_inst || !spvOpcodeIsConstant(constant_inst->opcode()) ||
value_instruction->type_id() != constant_inst->type_id()) {
return false;
}
// |message_.value_id| must be available at the insertion point.
return fuzzerutil::IdIsAvailableBeforeInstruction(
ir_context, instruction_to_insert_before, message_.value_id());
}
void TransformationPushIdThroughVariable::Apply(
opt::IRContext* ir_context,
TransformationContext* transformation_context) const {
auto value_instruction =
ir_context->get_def_use_mgr()->GetDef(message_.value_id());
// A pointer type instruction pointing to the value type must be defined.
auto pointer_type_id = fuzzerutil::MaybeGetPointerType(
ir_context, value_instruction->type_id(),
static_cast<SpvStorageClass>(message_.variable_storage_class()));
assert(pointer_type_id && "The required pointer type must be available.");
// Adds whether a global or local variable.
if (message_.variable_storage_class() == SpvStorageClassPrivate) {
fuzzerutil::AddGlobalVariable(ir_context, message_.variable_id(),
pointer_type_id, SpvStorageClassPrivate,
message_.initializer_id());
} else {
auto function_id = ir_context
->get_instr_block(FindInstruction(
message_.instruction_descriptor(), ir_context))
->GetParent()
->result_id();
fuzzerutil::AddLocalVariable(ir_context, message_.variable_id(),
pointer_type_id, function_id,
message_.initializer_id());
}
// First, insert the OpLoad instruction before |instruction_descriptor| and
// then insert the OpStore instruction before the OpLoad instruction.
fuzzerutil::UpdateModuleIdBound(ir_context, message_.value_synonym_id());
FindInstruction(message_.instruction_descriptor(), ir_context)
->InsertBefore(MakeUnique<opt::Instruction>(
ir_context, SpvOpLoad, value_instruction->type_id(),
message_.value_synonym_id(),
opt::Instruction::OperandList(
{{SPV_OPERAND_TYPE_ID, {message_.variable_id()}}})))
->InsertBefore(MakeUnique<opt::Instruction>(
ir_context, SpvOpStore, 0, 0,
opt::Instruction::OperandList(
{{SPV_OPERAND_TYPE_ID, {message_.variable_id()}},
{SPV_OPERAND_TYPE_ID, {message_.value_id()}}})));
ir_context->InvalidateAnalysesExceptFor(opt::IRContext::kAnalysisNone);
// We should be able to create a synonym of |value_id| if it's not irrelevant.
if (fuzzerutil::CanMakeSynonymOf(ir_context, *transformation_context,
value_instruction) &&
!transformation_context->GetFactManager()->IdIsIrrelevant(
message_.value_synonym_id())) {
// Adds the fact that |message_.value_synonym_id|
// and |message_.value_id| are synonymous.
transformation_context->GetFactManager()->AddFactDataSynonym(
MakeDataDescriptor(message_.value_synonym_id(), {}),
MakeDataDescriptor(message_.value_id(), {}));
}
}
protobufs::Transformation TransformationPushIdThroughVariable::ToMessage()
const {
protobufs::Transformation result;
*result.mutable_push_id_through_variable() = message_;
return result;
}
std::unordered_set<uint32_t> TransformationPushIdThroughVariable::GetFreshIds()
const {
return {message_.value_synonym_id(), message_.variable_id()};
}
} // namespace fuzz
} // namespace spvtools