SPIRV-Tools/source/fuzz/transformation_set_loop_control.h
Alastair Donaldson 253806adc4
spirv-fuzz: Add fuzzer pass to change loop controls (#2949)
A new pass that allows the fuzzer to change the 'loop control' operand
(and associated literal operands) of OpLoopMerge instructions.

Fixes #2938.
Fixes #2943.
2019-10-10 13:34:38 +01:00

80 lines
3.2 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.
#ifndef SOURCE_FUZZ_TRANSFORMATION_SET_LOOP_CONTROL_H_
#define SOURCE_FUZZ_TRANSFORMATION_SET_LOOP_CONTROL_H_
#include "source/fuzz/fact_manager.h"
#include "source/fuzz/protobufs/spirvfuzz_protobufs.h"
#include "source/fuzz/transformation.h"
#include "source/opt/ir_context.h"
namespace spvtools {
namespace fuzz {
class TransformationSetLoopControl : public Transformation {
public:
const static uint32_t kLoopControlMaskInOperandIndex = 2;
const static uint32_t kLoopControlFirstLiteralInOperandIndex = 3;
explicit TransformationSetLoopControl(
const protobufs::TransformationSetLoopControl& message);
TransformationSetLoopControl(uint32_t block_id, uint32_t loop_control,
uint32_t peel_count, uint32_t partial_count);
// - |message_.block_id| must be a block containing an OpLoopMerge
// instruction.
// - |message_.loop_control| must be a legal loop control mask that
// only uses controls available in the SPIR-V version associated with
// |context|, and must not add loop controls that are only valid in the
// presence of guarantees about what the loop does (e.g. MinIterations).
// - |message_.peel_count| (respectively |message_.partial_count|) must be
// zero PeelCount (respectively PartialCount) is set in
// |message_.loop_control|.
bool IsApplicable(opt::IRContext* context,
const FactManager& fact_manager) const override;
// - The loop control operand of the OpLoopMergeInstruction in
// |message_.block_id| is overwritten with |message_.loop_control|.
// - The literals associated with the loop control are updated to reflect any
// controls with associated literals that have been removed (e.g.
// MinIterations), and any that have been added (PeelCount and/or
// PartialCount).
void Apply(opt::IRContext* context, FactManager* fact_manager) const override;
protobufs::Transformation ToMessage() const override;
// Does the version of SPIR-V being used support the PartialCount loop
// control?
static bool PartialCountIsSupported(opt::IRContext* context);
// Does the version of SPIR-V being used support the PeelCount loop control?
static bool PeelCountIsSupported(opt::IRContext* context);
private:
// Returns true if and only if |loop_single_bit_mask| is *not* set in
// |existing_loop_control| but *is* set in |message_.loop_control|.
bool LoopControlBitIsAddedByTransformation(
SpvLoopControlMask loop_control_single_bit_mask,
uint32_t existing_loop_control_mask) const;
protobufs::TransformationSetLoopControl message_;
};
} // namespace fuzz
} // namespace spvtools
#endif // SOURCE_FUZZ_TRANSFORMATION_SET_LOOP_CONTROL_H_