fix BLOOM ONNX config (#19573)

* fix BLOOM ONNX config
- `value` params have `seq_len` as their 2nd axe as opposed to other models which have it as 3rd
Co-authored-by: lewtun <lewis.c.tunstall@gmail.com>

src/transformers/models/bloom/configuration_bloom.py

@@ -152,7 +152,6 @@ class BloomConfig(PretrainedConfig):
 
 
 class BloomOnnxConfig(OnnxConfigWithPast):
-
     torch_onnx_minimum_version = version.parse("1.12")
 
     def __init__(
@@ -171,7 +170,8 @@ class BloomOnnxConfig(OnnxConfigWithPast):
     def inputs(self) -> Mapping[str, Mapping[int, str]]:
         common_inputs = OrderedDict({"input_ids": {0: "batch", 1: "sequence"}})
         if self.use_past:
-            self.fill_with_past_key_values_(common_inputs, direction="inputs")
+            # BLOOM stores values on dynamic axis 2. For more details see: https://github.com/huggingface/transformers/pull/18344
+            self.fill_with_past_key_values_(common_inputs, direction="inputs", inverted_values_shape=True)
             common_inputs["attention_mask"] = {0: "batch", 1: "past_sequence + sequence"}
         else:
             common_inputs["attention_mask"] = {0: "batch", 1: "sequence"}

src/transformers/onnx/config.py

@@ -486,7 +486,9 @@ class OnnxConfigWithPast(OnnxConfig, ABC):
 
         return common_inputs
 
-    def fill_with_past_key_values_(self, inputs_or_outputs: Mapping[str, Mapping[int, str]], direction: str):
+    def fill_with_past_key_values_(
+        self, inputs_or_outputs: Mapping[str, Mapping[int, str]], direction: str, inverted_values_shape: bool = False
+    ):
         """
         Fill the input_or_outputs mapping with past_key_values dynamic axes considering.
 
@@ -494,6 +496,8 @@ class OnnxConfigWithPast(OnnxConfig, ABC):
             inputs_or_outputs: The mapping to fill.
             direction: either "inputs" or "outputs", it specifies whether input_or_outputs is the input mapping or the
                 output mapping, this is important for axes naming.
+            inverted_values_shape:
+                If `True`, store values on dynamic axis 1, else on axis 2.
 
         """
         if direction not in ["inputs", "outputs"]:
@@ -502,6 +506,9 @@ class OnnxConfigWithPast(OnnxConfig, ABC):
         name = "past_key_values" if direction == "inputs" else "present"
         for i in range(self.num_layers):
             inputs_or_outputs[f"{name}.{i}.key"] = {0: "batch", 2: "past_sequence + sequence"}
+            if inverted_values_shape:
+                inputs_or_outputs[f"{name}.{i}.value"] = {0: "batch", 1: "past_sequence + sequence"}
+            else:
                 inputs_or_outputs[f"{name}.{i}.value"] = {0: "batch", 2: "past_sequence + sequence"}
 
     def _flatten_past_key_values_(self, flattened_output, name, idx, t):