From 3a6efdd03c46c5ba08e43880d34260c02dd9999b Mon Sep 17 00:00:00 2001
From: Romain D <90720+Artefact2@users.noreply.github.com>
Date: Mon, 18 Mar 2024 09:04:41 +0100
Subject: [PATCH] convert : use f32 outtype for bf16 tensors (#6106)

The old behaviour is to use f16, but bf16 to f16 is not a lossless conversion.
Change the outtype to f32 to default to a lossless conversion.
---
 convert.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/convert.py b/convert.py
index 161430f3e..817cb6612 100755
--- a/convert.py
+++ b/convert.py
@@ -1167,9 +1167,9 @@ class OutputFile:
 def pick_output_type(model: LazyModel, output_type_str: str | None) -> GGMLFileType:
     wq_type = model[gguf.TENSOR_NAMES[gguf.MODEL_TENSOR.ATTN_Q].format(bid=0) + ".weight"].data_type
 
-    if output_type_str == "f32" or (output_type_str is None and wq_type == DT_F32):
+    if output_type_str == "f32" or (output_type_str is None and wq_type in (DT_F32, DT_BF16)):
         return GGMLFileType.AllF32
-    if output_type_str == "f16" or (output_type_str is None and wq_type in (DT_F16, DT_BF16)):
+    if output_type_str == "f16" or (output_type_str is None and wq_type == DT_F16):
         return GGMLFileType.MostlyF16
     if output_type_str == "q8_0":
         return GGMLFileType.MostlyQ8_0