third_party_spirv-tools/source/fuzz/transformation_add_local_variable.cpp
Alastair Donaldson 6382cbb497
spirv-fuzz: Avoid invalidating analyses in various transformations (#4205)
Avoids invalidating all analyses in transformations that add
constants, OpUndef and global and local variables.
2021-03-20 22:48:02 +00:00

104 lines
3.6 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 "source/fuzz/transformation_add_local_variable.h"
#include "source/fuzz/fuzzer_util.h"
namespace spvtools {
namespace fuzz {
TransformationAddLocalVariable::TransformationAddLocalVariable(
spvtools::fuzz::protobufs::TransformationAddLocalVariable message)
: message_(std::move(message)) {}
TransformationAddLocalVariable::TransformationAddLocalVariable(
uint32_t fresh_id, uint32_t type_id, uint32_t function_id,
uint32_t initializer_id, bool value_is_irrelevant) {
message_.set_fresh_id(fresh_id);
message_.set_type_id(type_id);
message_.set_function_id(function_id);
message_.set_initializer_id(initializer_id);
message_.set_value_is_irrelevant(value_is_irrelevant);
}
bool TransformationAddLocalVariable::IsApplicable(
opt::IRContext* ir_context, const TransformationContext& /*unused*/) const {
// The provided id must be fresh.
if (!fuzzerutil::IsFreshId(ir_context, message_.fresh_id())) {
return false;
}
// The pointer type id must indeed correspond to a pointer, and it must have
// function storage class.
auto type_instruction =
ir_context->get_def_use_mgr()->GetDef(message_.type_id());
if (!type_instruction || type_instruction->opcode() != SpvOpTypePointer ||
type_instruction->GetSingleWordInOperand(0) != SpvStorageClassFunction) {
return false;
}
// The initializer must...
auto initializer_instruction =
ir_context->get_def_use_mgr()->GetDef(message_.initializer_id());
// ... exist, ...
if (!initializer_instruction) {
return false;
}
// ... be a constant, ...
if (!spvOpcodeIsConstant(initializer_instruction->opcode())) {
return false;
}
// ... and have the same type as the pointee type.
if (initializer_instruction->type_id() !=
type_instruction->GetSingleWordInOperand(1)) {
return false;
}
// The function to which the local variable is to be added must exist.
return fuzzerutil::FindFunction(ir_context, message_.function_id());
}
void TransformationAddLocalVariable::Apply(
opt::IRContext* ir_context,
TransformationContext* transformation_context) const {
opt::Instruction* new_instruction = fuzzerutil::AddLocalVariable(
ir_context, message_.fresh_id(), message_.type_id(),
message_.function_id(), message_.initializer_id());
// Inform the def-use manager about the new instruction.
ir_context->get_def_use_mgr()->AnalyzeInstDefUse(new_instruction);
ir_context->set_instr_block(
new_instruction,
fuzzerutil::FindFunction(ir_context, message_.function_id())
->entry()
.get());
if (message_.value_is_irrelevant()) {
transformation_context->GetFactManager()->AddFactValueOfPointeeIsIrrelevant(
message_.fresh_id());
}
}
protobufs::Transformation TransformationAddLocalVariable::ToMessage() const {
protobufs::Transformation result;
*result.mutable_add_local_variable() = message_;
return result;
}
std::unordered_set<uint32_t> TransformationAddLocalVariable::GetFreshIds()
const {
return {message_.fresh_id()};
}
} // namespace fuzz
} // namespace spvtools