1#!/usr/bin/env python3
  2from __future__ import annotations
  3
  4import logging
  5import argparse
  6import os
  7import sys
  8from tqdm import tqdm
  9from pathlib import Path
 10
 11import numpy as np
 12
 13# Necessary to load the local gguf package
 14if "NO_LOCAL_GGUF" not in os.environ and (Path(__file__).parent.parent.parent.parent / 'gguf-py').exists():
 15    sys.path.insert(0, str(Path(__file__).parent.parent.parent))
 16
 17import gguf
 18
 19logger = logging.getLogger("gguf-convert-endian")
 20
 21
 22def byteswap_noop(tensor, block_offs):
 23    # this function is used when byteswapping is not needed
 24    pass
 25
 26
 27def byteswap_q4_0(tensor, block_offs):
 28    # Each block_q4_0 consists of an f16 delta (scaling factor) followed by 16 int8 quantizations.
 29
 30    # Byte-Swap f16 sized delta field
 31    delta = tensor.data[block_offs:block_offs + 2].view(dtype=np.uint16)
 32    delta.byteswap(inplace=True)
 33
 34
 35def byteswap_q8_0(tensor, block_offs):
 36    # Each block_q8_0 consists of an f16 delta (scaling factor) followed by 32 int8 quantizations.
 37
 38    # Byte-Swap f16 sized delta field
 39    delta = tensor.data[block_offs:block_offs + 2].view(dtype=np.uint16)
 40    delta.byteswap(inplace=True)
 41
 42
 43def byteswap_q4_k(tensor, block_offs):
 44    # Each block_q4_k consists of 2 f16 values followed by 140 int8 values.
 45
 46    # Byte-Swap f16 sized fields
 47    delta = tensor.data[block_offs:block_offs + 2].view(dtype=np.uint16)
 48    delta.byteswap(inplace=True)
 49
 50    delta = tensor.data[block_offs + 2:block_offs + 4].view(dtype=np.uint16)
 51    delta.byteswap(inplace=True)
 52
 53
 54def byteswap_q6_k(tensor, block_offs):
 55    # Each block_q6_k consists of 208 int8 values followed by 1 f16 value.
 56
 57    # Byte-Swap f16 sized field
 58    delta = tensor.data[block_offs + 208:block_offs + 210].view(dtype=np.uint16)
 59    delta.byteswap(inplace=True)
 60
 61
 62byteswap_tensors = {
 63    gguf.GGMLQuantizationType.Q4_0:  byteswap_q4_0,
 64    gguf.GGMLQuantizationType.Q8_0:  byteswap_q8_0,
 65    gguf.GGMLQuantizationType.Q4_K:  byteswap_q4_k,
 66    gguf.GGMLQuantizationType.Q6_K:  byteswap_q6_k,
 67    gguf.GGMLQuantizationType.MXFP4: byteswap_noop,
 68}
 69
 70
 71def convert_byteorder(reader: gguf.GGUFReader, args: argparse.Namespace) -> None:
 72    file_endian = reader.endianess.name
 73    if reader.byte_order == 'S':
 74        host_endian = 'BIG' if file_endian == 'LITTLE' else 'LITTLE'
 75    else:
 76        host_endian = file_endian
 77    order = host_endian if args.order == "native" else args.order.upper()
 78    logger.info(f"* Host is {host_endian} endian, GGUF file seems to be {file_endian} endian")
 79    if file_endian == order:
 80        logger.info(f"* File is already {order} endian. Nothing to do.")
 81        sys.exit(0)
 82    logger.info("* Checking tensors for conversion compatibility")
 83    for tensor in reader.tensors:
 84        if tensor.tensor_type not in byteswap_tensors and \
 85           tensor.tensor_type not in (
 86                gguf.GGMLQuantizationType.F32,
 87                gguf.GGMLQuantizationType.F16,
 88                gguf.GGMLQuantizationType.BF16,
 89           ):
 90            raise ValueError(f"Cannot handle type {tensor.tensor_type.name} for tensor {repr(tensor.name)}")
 91    logger.info(f"* Preparing to convert from {file_endian} to {order}")
 92    if args.dry_run:
 93        return
 94    logger.warning("*** Warning *** Warning *** Warning **")
 95    logger.warning("* This conversion process may damage the file. Ensure you have a backup.")
 96    if order != host_endian:
 97        logger.warning("* Requested endian differs from host, you will not be able to load the model on this machine.")
 98    logger.warning("* The file will be modified immediately, so if conversion fails or is interrupted")
 99    logger.warning("* the file will be corrupted. Enter exactly YES if you are positive you want to proceed:")
100    response = input("YES, I am sure> ")
101    if response != "YES":
102        logger.warning("You didn't enter YES. Okay then, see ya!")
103        sys.exit(0)
104    logger.info(f"* Converting fields ({len(reader.fields)})")
105    for idx, field in enumerate(reader.fields.values()):
106        logger.info(f"- {idx:4}: Converting field {repr(field.name)}, part count: {len(field.parts)}")
107        for part in field.parts:
108            part.byteswap(inplace=True)
109    logger.info(f"* Converting tensors ({len(reader.tensors)})")
110
111    for idx, tensor in enumerate(pbar := tqdm(reader.tensors, desc="Converting tensor")):
112        log_message = (
113            f"Converting tensor {repr(tensor.name)}, "
114            f"type={tensor.tensor_type.name}, "
115            f"elements={tensor.n_elements} "
116        )
117
118        # Byte-swap each part of the tensor's field
119        for part in tensor.field.parts:
120            part.byteswap(inplace=True)
121
122        # Byte-swap tensor data if necessary
123        if tensor.tensor_type in byteswap_tensors:
124            # first flatten structure
125            oldshape = tensor.data.shape
126            newshape = 1
127            for i in tensor.data.shape:
128                newshape *= i
129
130            tensor.data.resize(newshape)
131
132            block_size    = gguf.constants.GGML_QUANT_SIZES[tensor.tensor_type][1]
133            byteswap_func = byteswap_tensors[tensor.tensor_type]
134
135            n_blocks = len(tensor.data) // block_size
136            for block_num in (inner_pbar := tqdm(range(n_blocks), desc="Byte-swapping Blocks", leave=False)):
137                block_offs = block_num * block_size
138
139                byteswap_func(tensor, block_offs)
140
141                if block_num % 100000 == 0:
142                    inner_pbar.set_description(f"Byte-swapping Blocks [{(n_blocks - block_num) // n_blocks}]")
143
144            # restore old shape in case it's ever used
145            tensor.data.resize(oldshape)
146        elif tensor.tensor_type == gguf.GGMLQuantizationType.BF16:
147            # Special case for BF16
148            # It is 2-bytes data, but by default view loads it as 1-byte data.
149            # Change to correct view before byteswapping.
150            tensor.data.view(dtype=np.uint16).byteswap(inplace=True)
151        else:
152            # Handle other tensor types
153            tensor.data.byteswap(inplace=True)
154
155        pbar.set_description(log_message)
156
157    logger.info("* Completion")
158
159
160def main() -> None:
161    parser = argparse.ArgumentParser(description="Convert GGUF file byte order")
162    parser.add_argument(
163        "model", type=str,
164        help="GGUF format model filename",
165    )
166    parser.add_argument(
167        "order", type=str, choices=['big', 'little', 'native'],
168        help="Requested byte order",
169    )
170    parser.add_argument(
171        "--dry-run", action="store_true",
172        help="Don't actually change anything",
173    )
174    parser.add_argument("--verbose", action="store_true", help="increase output verbosity")
175
176    args = parser.parse_args(None if len(sys.argv) > 1 else ["--help"])
177
178    logging.basicConfig(level=logging.DEBUG if args.verbose else logging.INFO)
179
180    logger.info(f'* Loading: {args.model}')
181    reader = gguf.GGUFReader(args.model, 'r' if args.dry_run else 'r+')
182    convert_byteorder(reader, args)
183
184
185if __name__ == "__main__":
186    main()