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fogInSingularityfogInSingularity
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add py generator for decoder based on binary decode tree
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17 files changed

Lines changed: 436 additions & 13 deletions

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‎.gitignore‎

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*.log
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compile_commands.json
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.cache
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perf.data
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perf.data.old
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__pycache__
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# tests:
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*.o

‎src/isa/CMakeLists.txt‎

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@@ -21,6 +21,5 @@ target_link_libraries(isa
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sim-flags
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sim
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helpers
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softfloat
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)

‎src/isa/include/isa/ext_f.inc‎

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// name mask match
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// name mask match
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MNEMONIC(FLW, 0x0000707f, 0x00002007)
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MNEMONIC(FSW, 0x0000707f, 0x00002027)
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‎src/sim/CMakeLists.txt‎

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add_library(sim STATIC)
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add_subdirectory(decode)
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target_sources(sim
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PRIVATE
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source/elf_loader.cpp
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source/decode.cpp
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source/memory.cpp
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source/rv_sim.cpp
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source/dispatch.cpp
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sim-flags
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helpers
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isa
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decode
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spdlog
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elfio::elfio

‎src/sim/decode/CMakeLists.txt‎

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add_library(decode STATIC)
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add_subdirectory(pygen)
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set_source_files_properties("${DECODE_CPP_OUT}" PROPERTIES GENERATED TRUE)
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target_sources(decode PRIVATE "${DECODE_CPP_OUT}")
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add_dependencies(decode ${DECODE_CODEGEN_TARGET})
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target_include_directories(decode
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PUBLIC
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include
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)
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target_link_libraries(decode
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PRIVATE
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sim-flags
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helpers
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isa
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spdlog
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softfloat
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)
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src/sim/include/sim/decode.hpp renamed to src/sim/decode/include/decode/decode.hpp

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#include "isa/mnemonics.hpp"
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#include "isa/isa_defs.hpp"
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namespace sim {
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namespace sim::decode {
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isa::InsnMnemonic Decode(isa::UndecodedInsn insn);
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}
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} // namespace sim::decode
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#endif // DECODE_HPP_

‎src/sim/decode/pygen/CMakeLists.txt‎

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find_package(Python3 REQUIRED COMPONENTS Interpreter)
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set(DECODE_PYGEN_DIR "${CMAKE_CURRENT_LIST_DIR}")
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set(DECODE_DIR "${DECODE_PYGEN_DIR}/..") # decode/
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get_filename_component(DECODE_DIR "${DECODE_DIR}" ABSOLUTE) # normilize path
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set(GEN_SCRIPT "${DECODE_PYGEN_DIR}/gen_decoder.py")
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set(GEN_DEPS
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"${DECODE_PYGEN_DIR}/gen_decoder.py"
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"${DECODE_PYGEN_DIR}/insn_mnem.py"
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"${DECODE_PYGEN_DIR}/opcode_dtree.py"
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"${DECODE_PYGEN_DIR}/mnem_parse.py"
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"${DECODE_PYGEN_DIR}/emit_cpp.py"
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)
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set(LIN_CPP "${DECODE_DIR}/source/lin_decode.cpp")
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set(ISA_EXT_INC "${CMAKE_SOURCE_DIR}/src/isa/include/isa/isa_ext.inc")
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set(GEN_DIR "${CMAKE_CURRENT_BINARY_DIR}/generated")
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set(DECODE_CPP_OUT "${GEN_DIR}/decode.cpp")
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set(DOT_OUT "${GEN_DIR}/dtree.dot")
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set(COMPILE_DOT_SH "compile_dot.sh")
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# options
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set(DECODE_BACKEND "generated" CACHE STRING "Decode backend: linear|generated")
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set_property(CACHE DECODE_BACKEND PROPERTY STRINGS linear generated)
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option(DECODE_EMIT_DOT "Emit decode decision tree .dot during generation" OFF)
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set(DECODE_GEN_EXTRA_ARGS "" CACHE STRING "Extra args for gen_decoder.py (CMake list separated by ';')")
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# Build command depending on backend
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if (DECODE_BACKEND STREQUAL "generated")
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if (DECODE_EMIT_DOT)
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set(DOT_ARGS --dot "${DOT_OUT}")
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else()
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set(DOT_ARGS)
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endif()
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add_custom_command(
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OUTPUT "${DECODE_CPP_OUT}"
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COMMAND "${CMAKE_COMMAND}" -E make_directory "${GEN_DIR}"
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COMMAND "${Python3_EXECUTABLE}" "${GEN_SCRIPT}"
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--isa "${ISA_EXT_INC}"
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--output "${DECODE_CPP_OUT}"
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${DOT_ARGS}
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${DECODE_GEN_EXTRA_ARGS}
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COMMAND "${CMAKE_COMMAND}" -E copy_if_different "${DECODE_PYGEN_DIR}/${COMPILE_DOT_SH}" "${GEN_DIR}/${COMPILE_DOT_SH}"
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DEPENDS
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"${ISA_EXT_INC}"
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"${DECODE_PYGEN_DIR}/${COMPILE_DOT_SH}"
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${GEN_DEPS}
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WORKING_DIRECTORY "${DECODE_PYGEN_DIR}"
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COMMENT "Generating decoder.cpp (backend=generated)"
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VERBATIM
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)
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elseif (DECODE_BACKEND STREQUAL "linear")
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add_custom_command(
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OUTPUT "${DECODE_CPP_OUT}"
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COMMAND "${CMAKE_COMMAND}" -E make_directory "${GEN_DIR}"
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COMMAND "${CMAKE_COMMAND}" -E copy_if_different "${LIN_CPP}" "${DECODE_CPP_OUT}"
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DEPENDS "${LIN_CPP}"
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COMMENT "Preparing decoder.cpp (backend=linear)"
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VERBATIM
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)
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else()
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message(FATAL_ERROR "Unknown DECODE_BACKEND='${DECODE_BACKEND}'. Use linear|generated.")
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endif()
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add_custom_target(decode_codegen DEPENDS "${DECODE_CPP_OUT}")
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# Export outputs to decode
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set(DECODE_CPP_OUT "${DECODE_CPP_OUT}" PARENT_SCOPE)
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set(DECODE_CODEGEN_TARGET decode_codegen PARENT_SCOPE)

‎src/sim/decode/pygen/compile_dot.sh‎

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#/bin/bash
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dot -Tsvg $1 -o $1.svg

‎src/sim/decode/pygen/emit_cpp.py‎

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from opcode_dtree import DTree, DTreeLeaf, DTreeNode, DTreeTestBit
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from pathlib import Path
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def _node_gen(node: DTreeNode, depth: int = 0) -> str:
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indent = " " * depth
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if isinstance(node, DTreeLeaf):
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return f"{indent}return isa::InsnMnemonic::{node.insn_name};\n"
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cond_if = f"{indent}if (isa::IsBitSet(insn, {node.bit_idx})) {{\n"
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cond_else = f"{indent}}} else {{\n"
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cond_end = f"{indent}}}\n"
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return cond_if + _node_gen(node.one, depth=depth + 1) + cond_else + _node_gen(node.zero, depth=depth + 1) + cond_end
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def gen(op_dtree: DTree, namespace: str = "sim::decode") -> str:
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prologue = f"""
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// THIS CODE IS GENERATED
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// by decode/gen_decoder.py
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#include "decode/decode.hpp"
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#include "isa/isa_hlp.hpp"
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#include "isa/mnemonics.hpp"
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namespace {namespace} {{
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isa::InsnMnemonic Decode(isa::UndecodedInsn insn) {{
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"""
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epilogue = f"""
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}}
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}} // namespace {namespace}
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"""
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decode_body = _node_gen(op_dtree.get_root(), depth=1)
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return prologue + decode_body + epilogue
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def write_gen(gen_path: Path, opcode_dtree: DTree, namespace: str = "sim::decode"):
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gen_code = gen(opcode_dtree, namespace=namespace)
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gen_path.write_text(gen_code)

‎src/sim/decode/pygen/gen_decoder.py‎

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import argparse
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from pathlib import Path
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import mnem_parse
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import opcode_dtree
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import emit_cpp
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if __name__ == "__main__":
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parser = argparse.ArgumentParser()
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parser.add_argument("--isa", required=True, help="isa_ext.inc file path")
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parser.add_argument("--output", required=True, help="output file path")
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parser.add_argument("--dot", help="file path to .dot representation of decode tree")
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args = parser.parse_args()
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isa_path = Path(args.isa).resolve()
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mnems = mnem_parse.parse(isa_path)
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dtree = opcode_dtree.build_dtree(mnems)
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if args.dot:
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dot_path = Path(args.dot)
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dtree.write_dot(dot_path)
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cpp_path = Path(args.output)
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emit_cpp.write_gen(cpp_path, dtree)

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