mirror of
https://github.com/KhronosGroup/SPIRV-Tools
synced 2024-10-19 03:20:14 +00:00
fcb22ecf0f
Adds a virtual method, GetFreshIds(), to Transformation. Every transformation uses this to indicate which ids in its protobuf message are fresh ids. This means that when replaying a sequence of transformations the replayer can obtain a smallest id that is not in use by the module already and that will not be used by any transformation by necessity. Ids greater than or equal to this id can be used as overflow ids. Fixes #3851.
111 lines
4.0 KiB
C++
111 lines
4.0 KiB
C++
// Copyright (c) 2020 Vasyl Teliman
|
|
//
|
|
// 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_swap_conditional_branch_operands.h"
|
|
|
|
#include "source/fuzz/fuzzer_util.h"
|
|
#include "source/fuzz/instruction_descriptor.h"
|
|
|
|
namespace spvtools {
|
|
namespace fuzz {
|
|
|
|
TransformationSwapConditionalBranchOperands::
|
|
TransformationSwapConditionalBranchOperands(
|
|
const spvtools::fuzz::protobufs::
|
|
TransformationSwapConditionalBranchOperands& message)
|
|
: message_(message) {}
|
|
|
|
TransformationSwapConditionalBranchOperands::
|
|
TransformationSwapConditionalBranchOperands(
|
|
const protobufs::InstructionDescriptor& instruction_descriptor,
|
|
uint32_t fresh_id) {
|
|
*message_.mutable_instruction_descriptor() = instruction_descriptor;
|
|
message_.set_fresh_id(fresh_id);
|
|
}
|
|
|
|
bool TransformationSwapConditionalBranchOperands::IsApplicable(
|
|
opt::IRContext* ir_context, const TransformationContext& /*unused*/) const {
|
|
const auto* inst =
|
|
FindInstruction(message_.instruction_descriptor(), ir_context);
|
|
return fuzzerutil::IsFreshId(ir_context, message_.fresh_id()) && inst &&
|
|
inst->opcode() == SpvOpBranchConditional;
|
|
}
|
|
|
|
void TransformationSwapConditionalBranchOperands::Apply(
|
|
opt::IRContext* ir_context, TransformationContext* /*unused*/) const {
|
|
auto* branch_inst =
|
|
FindInstruction(message_.instruction_descriptor(), ir_context);
|
|
assert(branch_inst);
|
|
|
|
auto* block = ir_context->get_instr_block(branch_inst);
|
|
assert(block);
|
|
|
|
// Compute the last instruction in the |block| that allows us to insert
|
|
// OpLogicalNot above it.
|
|
auto iter = fuzzerutil::GetIteratorForInstruction(block, branch_inst);
|
|
if (!fuzzerutil::CanInsertOpcodeBeforeInstruction(SpvOpLogicalNot, iter)) {
|
|
// There might be a merge instruction before OpBranchConditional.
|
|
--iter;
|
|
}
|
|
|
|
assert(fuzzerutil::CanInsertOpcodeBeforeInstruction(SpvOpLogicalNot, iter) &&
|
|
"We should now be able to insert SpvOpLogicalNot before |iter|");
|
|
|
|
// Get the instruction whose result is used as a condition for
|
|
// OpBranchConditional.
|
|
const auto* condition_inst = ir_context->get_def_use_mgr()->GetDef(
|
|
branch_inst->GetSingleWordInOperand(0));
|
|
assert(condition_inst);
|
|
|
|
// We are swapping the labels in OpBranchConditional. This means that we must
|
|
// invert the guard as well. We are using OpLogicalNot for that purpose here.
|
|
iter.InsertBefore(MakeUnique<opt::Instruction>(
|
|
ir_context, SpvOpLogicalNot, condition_inst->type_id(),
|
|
message_.fresh_id(),
|
|
opt::Instruction::OperandList{
|
|
{SPV_OPERAND_TYPE_ID, {condition_inst->result_id()}}}));
|
|
|
|
fuzzerutil::UpdateModuleIdBound(ir_context, message_.fresh_id());
|
|
|
|
// Update OpBranchConditional condition operand.
|
|
branch_inst->GetInOperand(0).words[0] = message_.fresh_id();
|
|
|
|
// Swap label operands.
|
|
std::swap(branch_inst->GetInOperand(1), branch_inst->GetInOperand(2));
|
|
|
|
// Additionally, swap branch weights if present.
|
|
if (branch_inst->NumInOperands() > 3) {
|
|
std::swap(branch_inst->GetInOperand(3), branch_inst->GetInOperand(4));
|
|
}
|
|
|
|
// Make sure the changes are analyzed.
|
|
ir_context->InvalidateAnalysesExceptFor(
|
|
opt::IRContext::Analysis::kAnalysisNone);
|
|
}
|
|
|
|
protobufs::Transformation
|
|
TransformationSwapConditionalBranchOperands::ToMessage() const {
|
|
protobufs::Transformation result;
|
|
*result.mutable_swap_conditional_branch_operands() = message_;
|
|
return result;
|
|
}
|
|
|
|
std::unordered_set<uint32_t>
|
|
TransformationSwapConditionalBranchOperands::GetFreshIds() const {
|
|
return {message_.fresh_id()};
|
|
}
|
|
|
|
} // namespace fuzz
|
|
} // namespace spvtools
|