[Misc] Clean up input processing (#17582)

Signed-off-by: DarkLight1337 <tlleungac@connect.ust.hk>

tests/models/multimodal/pooling/test_intern_vit.py

@@ -6,6 +6,7 @@ from huggingface_hub import snapshot_download
 from transformers import AutoConfig, AutoModel, CLIPImageProcessor
 
 from vllm.distributed import cleanup_dist_env_and_memory
+from vllm.utils import STR_DTYPE_TO_TORCH_DTYPE
 
 from ....conftest import ImageTestAssets
 
@@ -14,6 +15,7 @@ from ....conftest import ImageTestAssets
 DOWNLOAD_PATTERN = ["*.json", "*.py", "*.safetensors", "*.txt", "*.model"]
 
 
+@torch.inference_mode()
 def run_intern_vit_test(
     image_assets: ImageTestAssets,
     model_id: str,
@@ -21,11 +23,12 @@ def run_intern_vit_test(
     dtype: str,
 ):
     model = snapshot_download(model_id, allow_patterns=DOWNLOAD_PATTERN)
+    torch_dtype = STR_DTYPE_TO_TORCH_DTYPE[dtype]
 
     img_processor = CLIPImageProcessor.from_pretrained(model)
     images = [asset.pil_image for asset in image_assets]
     pixel_values = [
-        img_processor(images, return_tensors='pt').pixel_values.to(dtype)
+        img_processor(images, return_tensors='pt').pixel_values.to(torch_dtype)
         for images in images
     ]
 
@@ -34,7 +37,7 @@ def run_intern_vit_test(
         config.norm_type = "rms_norm"
 
     hf_model = AutoModel.from_pretrained(model,
-                                         torch_dtype=dtype,
+                                         torch_dtype=torch_dtype,
                                          trust_remote_code=True).to("cuda")
     hf_outputs_per_image = [
         hf_model(pixel_value.to("cuda")).last_hidden_state
@@ -48,7 +51,7 @@ def run_intern_vit_test(
     del hf_model
     cleanup_dist_env_and_memory()
 
-    vllm_model = vllm_model.to("cuda", dtype)
+    vllm_model = vllm_model.to("cuda", torch_dtype)
     vllm_outputs_per_image = [
         vllm_model(pixel_values=pixel_value.to("cuda"))
         for pixel_value in pixel_values
@@ -66,9 +69,8 @@ def run_intern_vit_test(
     "OpenGVLab/InternViT-300M-448px",
     "OpenGVLab/InternViT-6B-448px-V1-5",
 ])
-@pytest.mark.parametrize("dtype", [torch.half])
-@torch.inference_mode()
-def test_models(image_assets, model_id, dtype: str) -> None:
+@pytest.mark.parametrize("dtype", ["half"])
+def test_models(dist_init, image_assets, model_id, dtype: str) -> None:
     run_intern_vit_test(
         image_assets,
         model_id,

vllm/engine/async_llm_engine.py

@@ -497,10 +497,6 @@ class _AsyncLLMEngine(LLMEngine):
             prompt["prompt_token_ids"] = [0
                                           ] * prompt["prompt_embeds"].shape[-2]
 
-        if self.tokenizer is not None:
-            tokenizer = await self.get_tokenizer_async(lora_request)
-            self._validate_token_prompt(prompt, tokenizer=tokenizer)
-
         processed_inputs = await self.input_preprocessor.preprocess_async(
             prompt,
             lora_request=lora_request,

vllm/engine/llm_engine.py

@@ -30,7 +30,7 @@ from vllm.entrypoints.openai.logits_processors import (
     get_logits_processors as get_openai_logits_processors)
 from vllm.executor.executor_base import ExecutorBase
 from vllm.inputs import ProcessorInputs, PromptType, SingletonInputs
-from vllm.inputs.parse import is_token_prompt, split_enc_dec_inputs
+from vllm.inputs.parse import split_enc_dec_inputs
 from vllm.inputs.preprocess import InputPreprocessor
 from vllm.logger import init_logger
 from vllm.logits_process import get_bad_words_logits_processors
@@ -759,11 +759,6 @@ class LLMEngine:
             seq_len = prompt["prompt_embeds"].shape[0]
             prompt["prompt_token_ids"] = [0] * seq_len
 
-        if self.tokenizer is not None:
-            self._validate_token_prompt(
-                prompt,
-                tokenizer=self.get_tokenizer(lora_request=lora_request))
-
         processed_inputs = self.input_preprocessor.preprocess(
             prompt,
             tokenization_kwargs=tokenization_kwargs,
@@ -782,27 +777,6 @@ class LLMEngine:
             priority=priority,
         )
 
-    def _validate_token_prompt(self, prompt: PromptType,
-                               tokenizer: AnyTokenizer):
-        # Guard against out-of-vocab tokens.
-        # For some tokenizers, tokenizer.decode will happily return empty text
-        # for token ids that are out of vocab, and we don't detect token ids
-        # that are greater than the max token id before running the model.
-        # However, these token ids will later crash a cuda kernel at runtime
-        # with an index out of bounds error. This will crash the entire engine.
-        # This needs to happen before multimodal input pre-processing, which
-        # may add dummy <image> tokens that aren't part of the tokenizer's
-        # vocabulary.
-        if is_token_prompt(prompt):
-            prompt_ids = prompt["prompt_token_ids"]
-            if len(prompt_ids) == 0:
-                # Empty prompt check is handled later
-                return
-            max_input_id = max(prompt_ids)
-            if max_input_id > tokenizer.max_token_id:
-                raise ValueError(
-                    "Token id {} is out of vocabulary".format(max_input_id))
-
     def _create_sequence_group_with_sampling(
         self,
         request_id: str,
@@ -2049,6 +2023,12 @@ class LLMEngine:
             else:
                 raise ValueError(f"The {prompt_type} prompt cannot be empty")
 
+        if tokenizer is not None:
+            max_input_id = max(prompt_ids, default=0)
+            if max_input_id > tokenizer.max_token_id:
+                raise ValueError(
+                    f"Token id {max_input_id} is out of vocabulary")
+
         max_prompt_len = self.model_config.max_model_len
         if len(prompt_ids) > max_prompt_len:
             if prompt_type == "encoder" and model_config.is_multimodal_model:

vllm/engine/protocol.py

@@ -83,6 +83,9 @@ class EngineClient(ABC):
         else:
             processed_inputs = preprocessor._prompt_to_llm_inputs(prompt)
 
+        if processed_inputs["type"] == "embeds":
+            raise NotImplementedError
+
         prompt_token_ids = processed_inputs["prompt_token_ids"]
         prompt_text = processed_inputs.get("prompt")
         multi_modal_data = processed_inputs.get("multi_modal_data")

vllm/entrypoints/llm.py

@@ -27,7 +27,7 @@ from vllm.entrypoints.score_utils import (_cosine_similarity,
                                           _validate_score_input_lens)
 from vllm.entrypoints.utils import _validate_truncation_size
 from vllm.inputs import PromptType, SingletonPrompt, TextPrompt, TokensPrompt
-from vllm.inputs.parse import is_token_prompt, parse_and_batch_prompt
+from vllm.inputs.parse import parse_and_batch_prompt
 from vllm.logger import init_logger
 from vllm.lora.request import LoRARequest
 from vllm.model_executor.guided_decoding.guided_fields import (
@@ -567,10 +567,12 @@ class LLM:
                 mm_kwargs["mm_processor_kwargs"] = prompt[
                     "mm_processor_kwargs"]
 
-            if is_token_prompt(prompt):
+            if "prompt_token_ids" in prompt:
+                prompt = cast(TokensPrompt, prompt)  # Needed for mypy
                 prompt_tokens = prompt["prompt_token_ids"]
             else:
                 prompt_tokens = tokenizer.encode(prompt["prompt"])
+
             instances.append(
                 BeamSearchInstance(prompt_tokens, logprobs=None, **mm_kwargs))
 

vllm/inputs/data.py

@@ -70,6 +70,11 @@ class EmbedsPrompt(TypedDict):
     prompt_embeds: torch.Tensor
     """The embeddings of the prompt."""
 
+    cache_salt: NotRequired[str]
+    """
+    Optional cache salt to be used for prefix caching.
+    """
+
 
 SingletonPrompt = Union[str, TextPrompt, TokensPrompt, EmbedsPrompt]
 """
@@ -195,13 +200,21 @@ class EmbedsInputs(TypedDict):
     prompt_embeds: torch.Tensor
     """The embeddings of the prompt."""
 
+    cache_salt: NotRequired[str]
+    """
+    Optional cache salt to be used for prefix caching.
+    """
+
 
-def embeds_inputs(prompt_embeds: torch.Tensor) -> EmbedsInputs:
+def embeds_inputs(
+    prompt_embeds: torch.Tensor,
+    cache_salt: Optional[str] = None,
+) -> EmbedsInputs:
     """Construct :class:`EmbedsInputs` from optional values."""
-    inputs = EmbedsInputs(
-        type="embeds",
-        prompt_embeds=prompt_embeds,
-    )
+    inputs = EmbedsInputs(type="embeds", prompt_embeds=prompt_embeds)
+
+    if cache_salt is not None:
+        inputs["cache_salt"] = cache_salt
 
     return inputs
 

vllm/inputs/parse.py

@@ -6,9 +6,9 @@ from typing_extensions import TypeIs
 
 from vllm.utils import is_list_of
 
-from .data import (EmbedsInputs, EmbedsPrompt, ExplicitEncoderDecoderPrompt,
-                   ProcessorInputs, PromptType, SingletonInputs,
-                   SingletonPrompt, TextPrompt, TokensPrompt)
+from .data import (EmbedsPrompt, ExplicitEncoderDecoderPrompt, ProcessorInputs,
+                   PromptType, SingletonInputs, SingletonPrompt, TextPrompt,
+                   TokensPrompt)
 
 
 class ParsedText(TypedDict):
@@ -90,6 +90,10 @@ class ParsedEmbedsPrompt(TypedDict):
     content: EmbedsPrompt
 
 
+ParsedSingletonPrompt = Union[ParsedStrPrompt, ParsedTextPrompt,
+                              ParsedTokensPrompt, ParsedEmbedsPrompt]
+
+
 @overload
 def parse_singleton_prompt(prompt: str) -> ParsedStrPrompt:
     ...
@@ -110,10 +114,7 @@ def parse_singleton_prompt(prompt: EmbedsPrompt) -> ParsedEmbedsPrompt:
     ...
 
 
-def parse_singleton_prompt(
-    prompt: SingletonPrompt,
-) -> Union[ParsedStrPrompt, ParsedTextPrompt, ParsedTokensPrompt,
-           ParsedEmbedsPrompt]:
+def parse_singleton_prompt(prompt: SingletonPrompt) -> ParsedSingletonPrompt:
     if isinstance(prompt, str):
         return ParsedStrPrompt(type="str", content=prompt)
     elif isinstance(prompt, dict):
@@ -131,23 +132,11 @@ def parse_singleton_prompt(
         "inputs must be a string, TextPrompt, TokensPrompt, or EmbedsPrompt")
 
 
-def is_token_prompt(prompt: PromptType) -> TypeIs[TokensPrompt]:
-    return isinstance(prompt, dict) and "prompt_token_ids" in prompt
-
-
-def is_embeds_prompt(prompt: PromptType) -> TypeIs[EmbedsPrompt]:
-    return isinstance(prompt, dict) and "prompt_embeds" in prompt
-
-
 def is_explicit_encoder_decoder_prompt(
         prompt: PromptType) -> TypeIs[ExplicitEncoderDecoderPrompt]:
     return isinstance(prompt, dict) and "encoder_prompt" in prompt
 
 
-def is_embeds_inputs(inputs: SingletonInputs) -> TypeIs[EmbedsInputs]:
-    return isinstance(inputs, dict) and inputs["type"] == "embeds"
-
-
 def split_enc_dec_inputs(
     inputs: ProcessorInputs,
 ) -> tuple[Optional[SingletonInputs], SingletonInputs]:

vllm/inputs/preprocess.py

@@ -14,14 +14,14 @@ from vllm.multimodal import MULTIMODAL_REGISTRY, MultiModalRegistry
 from vllm.multimodal.inputs import (MultiModalDataDict, MultiModalEncDecInputs,
                                     MultiModalInputs)
 from vllm.prompt_adapter.request import PromptAdapterRequest
+from vllm.transformers_utils.tokenizer import AnyTokenizer
 from vllm.transformers_utils.tokenizer_group import TokenizerGroup
 
-from .data import (DecoderOnlyInputs, EmbedsInputs, EncoderDecoderInputs,
-                   ProcessorInputs, PromptType, SingletonInputs,
-                   SingletonPrompt, TokenInputs, embeds_inputs, token_inputs)
-from .parse import (ParsedEmbedsPrompt, ParsedStrPrompt, ParsedTextPrompt,
-                    ParsedTokensPrompt, is_embeds_inputs,
-                    is_explicit_encoder_decoder_prompt, parse_singleton_prompt)
+from .data import (DecoderOnlyInputs, EmbedsInputs, EmbedsPrompt,
+                   EncoderDecoderInputs, ProcessorInputs, PromptType,
+                   SingletonInputs, SingletonPrompt, TextPrompt, TokenInputs,
+                   TokensPrompt, embeds_inputs, token_inputs)
+from .parse import is_explicit_encoder_decoder_prompt, parse_singleton_prompt
 
 logger = init_logger(__name__)
 
@@ -140,13 +140,10 @@ class InputPreprocessor:
         """
         Prepares `decoder_input_ids` for generation with encoder-decoder models.
 
-        Based on
-
-        https://github.com/huggingface/transformers/blob/
-        4037a2b5b1278736e566aec12e169100275545ea/
-        src/transformers/generation/utils.py
-
-        specifically GenerationMixin._prepare_decoder_input_ids_for_generation()
+        Based on:
+        https://github.com/huggingface/transformers/blob/4037a2b5b1278736e566aec12e169100275545ea/src/transformers/generation/utils.py
+        specifically,
+        `GenerationMixin._prepare_decoder_input_ids_for_generation()`.
 
         Arguments:
 
@@ -183,6 +180,23 @@ class InputPreprocessor:
 
         return prompt_token_ids
 
+    def _get_tokenization_kw(
+        self,
+        overrides: Optional[dict[str, Any]] = None,
+    ) -> dict[str, Any]:
+        kwargs = dict[str, Any]()
+
+        if self.model_config.hf_config.model_type == "whisper":
+            # For Whisper, special tokens should be provided by the user based
+            # on the task and language of their request. Also needed to avoid
+            # appending an EOS token to the prompt which disrupts generation.
+            kwargs["add_special_tokens"] = False
+
+        if overrides:
+            kwargs.update(overrides)
+
+        return kwargs
+
     def _tokenize_prompt(
         self,
         prompt: str,
@@ -194,18 +208,11 @@ class InputPreprocessor:
         corresponding token IDs.
         """
         tokenizer = self.get_tokenizer_group()
-        if tokenization_kwargs is None:
-            tokenization_kwargs = {}
+        tokenization_kwargs = self._get_tokenization_kw(tokenization_kwargs)
 
-        if self.model_config.hf_config.model_type == "whisper":
-            # For Whisper, special tokens should be provided by the user based
-            # on the task and language of their request. Also needed to avoid
-            # appending an EOS token to the prompt which disrupts generation.
-            tokenization_kwargs["add_special_tokens"] = False
+        encoder_config = self.model_config.encoder_config
 
-        if (self.model_config.encoder_config is not None
-                and self.model_config.encoder_config.get(
-                    "do_lower_case", False)):
+        if encoder_config and encoder_config.get("do_lower_case", False):
             prompt = prompt.lower()
 
         return tokenizer.encode(prompt=prompt,
@@ -220,18 +227,36 @@ class InputPreprocessor:
     ) -> list[int]:
         """Async version of :meth:`_tokenize_prompt`."""
         tokenizer = self.get_tokenizer_group()
-        if tokenization_kwargs is None:
-            tokenization_kwargs = {}
+        tokenization_kwargs = self._get_tokenization_kw(tokenization_kwargs)
 
-        if self.model_config.hf_config.model_type == "whisper":
-            # For Whisper, special tokens should be provided by the user based
-            # on the task and language of their request. Also needed to avoid
-            # appending an EOS token to the prompt which disrupts generation.
-            tokenization_kwargs["add_special_tokens"] = False
         return await tokenizer.encode_async(prompt=prompt,
                                             lora_request=lora_request,
                                             **tokenization_kwargs)
 
+    def _get_mm_tokenizer(
+        self,
+        lora_request: Optional[LoRARequest],
+    ) -> AnyTokenizer:
+        # PrithviGeoSpatialMAE needs to be initialized without a tokenizer
+        # while using also multi-modal input
+        if not self.tokenizer:
+            return cast(AnyTokenizer, object())  # Dummy
+
+        tokenizer_group = self.get_tokenizer_group()
+        return tokenizer_group.get_lora_tokenizer(lora_request)
+
+    async def _get_mm_tokenizer_async(
+        self,
+        lora_request: Optional[LoRARequest],
+    ) -> AnyTokenizer:
+        # PrithviGeoSpatialMAE needs to be initialized without a tokenizer
+        # while using also multi-modal input
+        if not self.tokenizer:
+            return cast(AnyTokenizer, object())  # Dummy
+
+        tokenizer_group = self.get_tokenizer_group()
+        return await tokenizer_group.get_lora_tokenizer_async(lora_request)
+
     def _process_multimodal(
         self,
         prompt: Union[str, list[int]],
@@ -244,13 +269,7 @@ class InputPreprocessor:
         Apply the model's multi-modal processor to a multi-modal prompt,
         returning the corresponding token IDs and metadata.
         """
-        # At the moment on model (PrithviGeoSpatialMAE) requires to be
-        # initialized without a tokenizer while using also multi-modal input
-        if not self.tokenizer:
-            tokenizer = object()  # Dummy
-        else:
-            tokenizer_group = self.get_tokenizer_group()
-            tokenizer = tokenizer_group.get_lora_tokenizer(lora_request)
+        tokenizer = self._get_mm_tokenizer(lora_request)
 
         mm_processor = self.mm_registry.create_processor(self.model_config,
                                                          tokenizer=tokenizer)
@@ -270,14 +289,7 @@ class InputPreprocessor:
         return_mm_hashes: bool = False,
     ) -> MultiModalInputs:
         """Async version of :meth:`_process_multimodal`."""
-        # At the moment on model (PrithviGeoSpatialMAE) requires to be
-        # initialized without a tokenizer while using also multi-modal input
-        if not self.tokenizer:
-            tokenizer = object()  # Dummy
-        else:
-            tokenizer_group = self.get_tokenizer_group()
-            tokenizer = await tokenizer_group.get_lora_tokenizer_async(
-                lora_request)
+        tokenizer = await self._get_mm_tokenizer_async(lora_request)
 
         mm_processor = self.mm_registry.create_processor(self.model_config,
                                                          tokenizer=tokenizer)
@@ -287,28 +299,160 @@ class InputPreprocessor:
         return mm_processor.apply(prompt, mm_data, mm_processor_kwargs,
                                   return_mm_hashes)
 
-    def _get_prompt_data(self, parsed_prompt: Union[ParsedStrPrompt,
-                                                    ParsedTextPrompt,
-                                                    ParsedTokensPrompt]):
-        prompt_text = None
-        prompt_token_ids = None
-        token_type_ids = None
-        cache_salt = None
+    def _process_embeds(
+        self,
+        parsed_content: EmbedsPrompt,
+    ) -> EmbedsInputs:
+        if envs.VLLM_USE_V1:
+            raise ValueError("prompt_embeds is only available in V0.")
+
+        prompt_embeds = parsed_content["prompt_embeds"]
 
-        if parsed_prompt["type"] == "str":
-            prompt_text = parsed_prompt["content"]
+        # prompt_embeds must be (seq_len, hidden_size), but if the user
+        # passes in a batch of size 1, i.e. (1, seq_len, hidden_size),
+        # we can unambiguously process the intent by squeezing the batch
+        # dimension.
+        if prompt_embeds.ndim == 3:
+            prompt_embeds = prompt_embeds.squeeze(dim=0)
+
+        if prompt_embeds.ndim != 2:
+            raise ValueError(
+                "prompt_embeds must be of shape (seq_len, hidden_size).")
+
+        return embeds_inputs(prompt_embeds=prompt_embeds,
+                             cache_salt=parsed_content.get("cache_salt"))
+
+    async def _process_embeds_async(
+        self,
+        parsed_content: EmbedsPrompt,
+    ) -> EmbedsInputs:
+        return self._process_embeds(parsed_content)
+
+    def _process_tokens(
+        self,
+        parsed_content: TokensPrompt,
+        lora_request: Optional[LoRARequest] = None,
+        return_mm_hashes: bool = False,
+    ) -> Union[TokenInputs, MultiModalInputs]:
+        prompt_token_ids = parsed_content["prompt_token_ids"]
+        token_type_ids = parsed_content.get("token_type_ids")
+
+        inputs: Union[TokenInputs, MultiModalInputs]
+        if multi_modal_data := parsed_content.get("multi_modal_data"):
+            inputs = self._process_multimodal(
+                prompt_token_ids,
+                multi_modal_data,
+                parsed_content.get("mm_processor_kwargs"),
+                lora_request=lora_request,
+                return_mm_hashes=return_mm_hashes,
+            )
         else:
-            cache_salt = parsed_prompt["content"].get("cache_salt")
-            if parsed_prompt["type"] == "text":
-                prompt_text = parsed_prompt["content"]["prompt"]
-            elif parsed_prompt["type"] == "tokens":
-                prompt_token_ids = parsed_prompt["content"].get(
-                    "prompt_token_ids")
-                token_type_ids = parsed_prompt["content"].get("token_type_ids")
-            else:
-                assert_never(parsed_prompt)
+            inputs = token_inputs(
+                prompt_token_ids=prompt_token_ids,
+                token_type_ids=token_type_ids,
+            )
+
+        if cache_salt := parsed_content.get("cache_salt"):
+            inputs["cache_salt"] = cache_salt
+
+        return inputs
+
+    async def _process_tokens_async(
+        self,
+        parsed_content: TokensPrompt,
+        lora_request: Optional[LoRARequest] = None,
+        return_mm_hashes: bool = False,
+    ) -> Union[TokenInputs, MultiModalInputs]:
+        prompt_token_ids = parsed_content["prompt_token_ids"]
+        token_type_ids = parsed_content.get("token_type_ids")
+
+        inputs: Union[TokenInputs, MultiModalInputs]
+        if multi_modal_data := parsed_content.get("multi_modal_data"):
+            inputs = await self._process_multimodal_async(
+                prompt_token_ids,
+                multi_modal_data,
+                parsed_content.get("mm_processor_kwargs"),
+                lora_request=lora_request,
+                return_mm_hashes=return_mm_hashes,
+            )
+        else:
+            inputs = token_inputs(
+                prompt_token_ids=prompt_token_ids,
+                token_type_ids=token_type_ids,
+            )
+
+        if cache_salt := parsed_content.get("cache_salt"):
+            inputs["cache_salt"] = cache_salt
+
+        return inputs
+
+    def _process_text(
+        self,
+        parsed_content: TextPrompt,
+        tokenization_kwargs: Optional[dict[str, Any]] = None,
+        lora_request: Optional[LoRARequest] = None,
+        return_mm_hashes: bool = False,
+    ) -> Union[TokenInputs, MultiModalInputs]:
+        prompt_text = parsed_content["prompt"]
+
+        inputs: Union[TokenInputs, MultiModalInputs]
+        if multi_modal_data := parsed_content.get("multi_modal_data"):
+            inputs = self._process_multimodal(
+                prompt_text,
+                multi_modal_data,
+                parsed_content.get("mm_processor_kwargs"),
+                lora_request=lora_request,
+                return_mm_hashes=return_mm_hashes,
+            )
+        else:
+            prompt_token_ids = self._tokenize_prompt(
+                prompt_text,
+                lora_request=lora_request,
+                tokenization_kwargs=tokenization_kwargs,
+            )
+            inputs = token_inputs(
+                prompt=prompt_text,
+                prompt_token_ids=prompt_token_ids,
+            )
+
+        if cache_salt := parsed_content.get("cache_salt"):
+            inputs["cache_salt"] = cache_salt
+
+        return inputs
 
-        return prompt_text, prompt_token_ids, token_type_ids, cache_salt
+    async def _process_text_async(
+        self,
+        parsed_content: TextPrompt,
+        tokenization_kwargs: Optional[dict[str, Any]] = None,
+        lora_request: Optional[LoRARequest] = None,
+        return_mm_hashes: bool = False,
+    ) -> Union[TokenInputs, MultiModalInputs]:
+        prompt_text = parsed_content["prompt"]
+
+        inputs: Union[TokenInputs, MultiModalInputs]
+        if multi_modal_data := parsed_content.get("multi_modal_data"):
+            inputs = await self._process_multimodal_async(
+                prompt_text,
+                multi_modal_data,
+                parsed_content.get("mm_processor_kwargs"),
+                lora_request=lora_request,
+                return_mm_hashes=return_mm_hashes,
+            )
+        else:
+            prompt_token_ids = await self._tokenize_prompt_async(
+                prompt_text,
+                lora_request=lora_request,
+                tokenization_kwargs=tokenization_kwargs,
+            )
+            inputs = token_inputs(
+                prompt=prompt_text,
+                prompt_token_ids=prompt_token_ids,
+            )
+
+        if cache_salt := parsed_content.get("cache_salt"):
+            inputs["cache_salt"] = cache_salt
+
+        return inputs
 
     def _prompt_to_llm_inputs(
         self,
@@ -333,39 +477,28 @@ class InputPreprocessor:
         parsed = parse_singleton_prompt(prompt)
 
         if parsed["type"] == "embeds":
-            return self._process_prompt_embeds(parsed)
-
-        prompt_text, prompt_token_ids, token_type_ids, cache_salt = \
-            self._get_prompt_data(parsed)
-
-        # If multimodal data is present, process and return immediately
-        if parsed["type"] != "str" and parsed["content"].get(
-                "multi_modal_data") is not None:
-            inputs = self._process_multimodal(
-                prompt_text if prompt_text is not None else prompt_token_ids,
-                parsed["content"]["multi_modal_data"],
-                parsed["content"].get("mm_processor_kwargs"),
+            return self._process_embeds(parsed["content"])
+        if parsed["type"] == "tokens":
+            return self._process_tokens(
+                parsed["content"],
                 lora_request=lora_request,
                 return_mm_hashes=return_mm_hashes,
             )
-            if cache_salt is not None:
-                inputs["cache_salt"] = cache_salt
-            return inputs
-
-        if prompt_token_ids is None:
-            prompt_token_ids = self._tokenize_prompt(
-                prompt_text,
+        if parsed["type"] == "text":
+            return self._process_text(
+                parsed["content"],
+                tokenization_kwargs=tokenization_kwargs,
                 lora_request=lora_request,
+                return_mm_hashes=return_mm_hashes,
+            )
+        if parsed["type"] == "str":
+            return self._process_text(
+                TextPrompt(prompt=parsed["content"]),
                 tokenization_kwargs=tokenization_kwargs,
+                lora_request=lora_request,
+                return_mm_hashes=return_mm_hashes,
             )
 
-        return token_inputs(
-            prompt=prompt_text,
-            prompt_token_ids=prompt_token_ids,
-            token_type_ids=token_type_ids,
-            cache_salt=cache_salt,
-        )
-
         assert_never(parsed)
 
     async def _prompt_to_llm_inputs_async(
@@ -375,79 +508,49 @@ class InputPreprocessor:
         lora_request: Optional[LoRARequest] = None,
         return_mm_hashes: bool = False,
     ) -> SingletonInputs:
-        """Async version of :meth:`_extract_prompt_components`."""
+        """Async version of :meth:`_prompt_to_llm_inputs`."""
         parsed = parse_singleton_prompt(prompt)
 
         if parsed["type"] == "embeds":
-            return self._process_prompt_embeds(parsed)
-
-        prompt_text, prompt_token_ids, token_type_ids, cache_salt = \
-            self._get_prompt_data(parsed)
-
-        if parsed["type"] != "str" and parsed["content"].get(
-                "multi_modal_data") is not None:
-            inputs = await self._process_multimodal_async(
-                prompt_token_ids if prompt_text is None else prompt_text,
-                parsed["content"]["multi_modal_data"],
-                parsed["content"].get("mm_processor_kwargs"),
+            return await self._process_embeds_async(parsed["content"])
+        if parsed["type"] == "tokens":
+            return await self._process_tokens_async(
+                parsed["content"],
                 lora_request=lora_request,
                 return_mm_hashes=return_mm_hashes,
             )
-            if cache_salt is not None:
-                inputs["cache_salt"] = cache_salt
-            return inputs
-
-        if prompt_token_ids is None:
-            prompt_token_ids = await self._tokenize_prompt_async(
-                prompt_text,
+        if parsed["type"] == "text":
+            return await self._process_text_async(
+                parsed["content"],
+                tokenization_kwargs=tokenization_kwargs,
                 lora_request=lora_request,
+                return_mm_hashes=return_mm_hashes,
+            )
+        if parsed["type"] == "str":
+            return await self._process_text_async(
+                TextPrompt(prompt=parsed["content"]),
                 tokenization_kwargs=tokenization_kwargs,
+                lora_request=lora_request,
+                return_mm_hashes=return_mm_hashes,
             )
 
-        return token_inputs(
-            prompt=prompt_text,
-            prompt_token_ids=prompt_token_ids,
-            token_type_ids=token_type_ids,
-            cache_salt=cache_salt,
-        )
-
-    def _process_prompt_embeds(self,
-                               parsed: ParsedEmbedsPrompt) -> EmbedsInputs:
-        if envs.VLLM_USE_V1:
-            raise ValueError("prompt_embeds is only available in V0.")
-
-        prompt_embeds_content = parsed["content"]
-
-        prompt_embeds = prompt_embeds_content["prompt_embeds"]
-
-        # prompt_embeds must be (seq_len, hidden_size), but if the user
-        # passes in a batch of size 1, i.e. (1, seq_len, hidden_size),
-        # we can unambiguously process the intent by squeezing the batch
-        # dimension.
-        if prompt_embeds.ndim == 3 and prompt_embeds.shape[0] == 1:
-            prompt_embeds = prompt_embeds.squeeze(dim=0)
-
-        if prompt_embeds.ndim != 2:
-            raise ValueError(
-                "prompt_embeds must be of shape (seq_len, hidden_size).")
-
-        return embeds_inputs(prompt_embeds=prompt_embeds)
-
         assert_never(parsed)
 
     def _build_enc_dec_llm_inputs(
         self,
-        encoder_inputs: Union[TokenInputs, MultiModalInputs],
-        decoder_inputs: Optional[Union[TokenInputs, MultiModalInputs]],
+        encoder_inputs: SingletonInputs,
+        decoder_inputs: Optional[SingletonInputs],
     ) -> EncoderDecoderInputs:
-        if (encoder_inputs["type"] == "token"
-                or encoder_inputs["type"] == "multimodal"):
-            pass
-        else:
-            assert_never(encoder_inputs)  # type: ignore[arg-type]
+        if (encoder_inputs["type"] == "embeds"
+                or decoder_inputs and decoder_inputs["type"] == "embeds"):
+            raise ValueError("Embedding inputs are not supported for encoder-"
+                             "decoder models")
 
-        # Mypy does not correctly infer that EmbedsInputs is impossible
-        assert "prompt_token_ids" in encoder_inputs
+        # Needed for mypy
+        encoder_inputs = cast(Union[TokenInputs, MultiModalInputs],
+                              encoder_inputs)
+        decoder_inputs = cast(Optional[Union[TokenInputs, MultiModalInputs]],
+                              decoder_inputs)
 
         if decoder_inputs is None:
             if self.model_config.hf_config.model_type == "whisper":
@@ -460,74 +563,78 @@ class InputPreprocessor:
                 dec_token_ids = self._prepare_decoder_input_ids_for_generation(
                     None)
             decoder_inputs = token_inputs(dec_token_ids)
-        elif (decoder_inputs["type"] == "token"
-              or decoder_inputs["type"] == "multimodal"):
-            dec_token_ids = self._prepare_decoder_input_ids_for_generation(
-                decoder_inputs["prompt_token_ids"])
-            decoder_inputs["prompt_token_ids"] = dec_token_ids
-
+        else:
             if "multi_modal_data" in decoder_inputs:
                 raise ValueError("Multi-modal decoder inputs of encoder-"
                                  "decoder models are not supported yet")
-        else:
-            assert_never(encoder_inputs)  # type: ignore[arg-type]
+
+            dec_token_ids = self._prepare_decoder_input_ids_for_generation(
+                decoder_inputs["prompt_token_ids"])
+            decoder_inputs["prompt_token_ids"] = dec_token_ids
 
         return EncoderDecoderInputs(
             encoder=encoder_inputs,
             decoder=decoder_inputs,
         )
 
-    def _separate_enc_dec_inputs_from_mm_processor_outputs(
+    def _split_enc_dec_mm_inputs(
         self,
-        inputs: SingletonInputs,
-        decoder_inputs_to_override: Optional[Union[TokenInputs,
-                                                   MultiModalInputs]] = None,
+        inputs: Union[SingletonInputs, MultiModalEncDecInputs],
+        decoder_inputs_to_override: Optional[SingletonInputs] = None,
     ) -> tuple[SingletonInputs, SingletonInputs]:
         """
         For encoder/decoder models only:
         Separate Encoder/Decoder inputs from a MultiModalEncDecInputs
         """
+        if (inputs["type"] == "embeds" or decoder_inputs_to_override
+                and decoder_inputs_to_override["type"] == "embeds"):
+            raise ValueError("Embedding inputs are not supported for encoder-"
+                             "decoder models")
+
+        # Needed for mypy
+        inputs = cast(
+            Union[TokenInputs, MultiModalInputs, MultiModalEncDecInputs],
+            inputs,
+        )
+        decoder_inputs_to_override = cast(
+            Optional[Union[TokenInputs, MultiModalInputs]],
+            decoder_inputs_to_override,
+        )
+
         encoder_inputs: SingletonInputs
         decoder_inputs: SingletonInputs
-        if inputs["type"] == "multimodal":
-            # Multimodal data inputs
-            assert ("encoder_prompt" in inputs
-                    and "encoder_prompt_token_ids" in inputs)
+
+        if inputs["type"] == "multimodal":  # Multimodal data inputs
+            if not ("encoder_prompt" in inputs
+                    and "encoder_prompt_token_ids" in inputs):
+                raise RuntimeError("You should register an encoder-decoder "
+                                   "multi-modal processor for encoder-decoder "
+                                   "models.")
             inputs = cast(MultiModalEncDecInputs, inputs)
+
             encoder_inputs = token_inputs(
                 prompt=inputs["encoder_prompt"],
                 prompt_token_ids=inputs["encoder_prompt_token_ids"],
             )
-            if decoder_inputs_to_override is not None:
-                decoder_inputs = MultiModalInputs(
-                    type="multimodal",
-                    prompt=decoder_inputs_to_override.get("prompt", ""),
-                    prompt_token_ids=decoder_inputs_to_override[
-                        "prompt_token_ids"],
-                    mm_kwargs=inputs["mm_kwargs"],
-                    mm_hashes=inputs["mm_hashes"],
-                    mm_placeholders=inputs["mm_placeholders"],
-                )
-            else:
-                decoder_inputs = MultiModalInputs(
-                    type="multimodal",
-                    prompt=inputs["prompt"],
-                    prompt_token_ids=inputs["prompt_token_ids"],
-                    mm_kwargs=inputs["mm_kwargs"],
-                    mm_hashes=inputs["mm_hashes"],
-                    mm_placeholders=inputs["mm_placeholders"],
-                )
 
-            cache_salt = inputs.get("cache_salt")
-            if cache_salt is not None:
+            decoder_prompt_inputs = decoder_inputs_to_override or inputs
+            decoder_inputs = MultiModalInputs(
+                type="multimodal",
+                prompt=decoder_prompt_inputs.get("prompt", ""),
+                prompt_token_ids=decoder_prompt_inputs["prompt_token_ids"],
+                mm_kwargs=inputs["mm_kwargs"],
+                mm_hashes=inputs["mm_hashes"],
+                mm_placeholders=inputs["mm_placeholders"],
+            )
+            if cache_salt := inputs.get("cache_salt"):
                 decoder_inputs["cache_salt"] = cache_salt
 
-        elif inputs["type"] == "token":
-            # Text-only inputs
+        elif inputs["type"] == "token":  # Text-only inputs
             encoder_inputs = token_inputs(prompt="", prompt_token_ids=[])
             decoder_inputs = decoder_inputs_to_override or inputs
         else:
             assert_never(inputs)  # type: ignore[arg-type]
+
         return encoder_inputs, decoder_inputs
 
     def _process_encoder_decoder_prompt(
@@ -580,11 +687,9 @@ class InputPreprocessor:
             # For multimodal model, override decoder prompt from processor
             # with explicit decoder prompt.
             if self.model_config.is_multimodal_model:
-                assert decoder_inputs is None or not is_embeds_inputs(
-                    decoder_inputs)
                 encoder_inputs, decoder_inputs = (
-                    self._separate_enc_dec_inputs_from_mm_processor_outputs(
-                        encoder_inputs, decoder_inputs))
+                    self._split_enc_dec_mm_inputs(encoder_inputs,
+                                                  decoder_inputs))
         else:
             inputs = self._prompt_to_llm_inputs(
                 prompt,
@@ -593,16 +698,11 @@ class InputPreprocessor:
             if self.model_config.is_multimodal_model:
                 # Encoder-Decoder Multimodal model
                 encoder_inputs, decoder_inputs = (
-                    self._separate_enc_dec_inputs_from_mm_processor_outputs(
-                        inputs))
+                    self._split_enc_dec_mm_inputs(inputs))
             else:
                 encoder_inputs = inputs
                 decoder_inputs = None
 
-        # Mypy does not do type inference well with TypedDicts with Literal
-        # values.
-        assert not is_embeds_inputs(encoder_inputs)
-        assert decoder_inputs is None or not is_embeds_inputs(decoder_inputs)
         return self._build_enc_dec_llm_inputs(encoder_inputs, decoder_inputs)
 
     async def _process_encoder_decoder_prompt_async(
@@ -635,11 +735,9 @@ class InputPreprocessor:
             # For multimodal model, override decoder prompt from processor
             # with explicit decoder prompt.
             if self.model_config.is_multimodal_model:
-                assert decoder_inputs is None or not is_embeds_inputs(
-                    decoder_inputs)
                 encoder_inputs, decoder_inputs = (
-                    self._separate_enc_dec_inputs_from_mm_processor_outputs(
-                        encoder_inputs, decoder_inputs))
+                    self._split_enc_dec_mm_inputs(encoder_inputs,
+                                                  decoder_inputs))
         else:
             inputs = await self._prompt_to_llm_inputs_async(
                 prompt,
@@ -648,16 +746,11 @@ class InputPreprocessor:
             if self.model_config.is_multimodal_model:
                 # Encoder-Decoder Multimodal model
                 encoder_inputs, decoder_inputs = (
-                    self._separate_enc_dec_inputs_from_mm_processor_outputs(
-                        inputs))
+                    self._split_enc_dec_mm_inputs(inputs))
             else:
                 encoder_inputs = inputs
                 decoder_inputs = None
 
-        # Mypy does not do type inference well with TypedDicts with Literal
-        # values.
-        assert not is_embeds_inputs(encoder_inputs)
-        assert decoder_inputs is None or not is_embeds_inputs(decoder_inputs)
         return self._build_enc_dec_llm_inputs(encoder_inputs, decoder_inputs)
 
     def _build_decoder_only_llm_inputs(
@@ -665,19 +758,13 @@ class InputPreprocessor:
         prompt_inputs: DecoderOnlyInputs,
         prompt_adapter_request: Optional[PromptAdapterRequest],
     ) -> DecoderOnlyInputs:
-        if (prompt_inputs["type"] == "token"
-                or prompt_inputs["type"] == "multimodal"):
-            # Mypy does not do type inference well with typedicts and Literal
-            # values
-            assert not is_embeds_inputs(prompt_inputs)
+        if "prompt_token_ids" in prompt_inputs:
+            prompt_inputs = cast(Union[TokenInputs, MultiModalInputs],
+                                 prompt_inputs)  # Needed for mypy
             prompt_inputs["prompt_token_ids"] = self._apply_prompt_adapter(
                 prompt_inputs["prompt_token_ids"],
                 prompt_adapter_request=prompt_adapter_request,
             )
-        elif (prompt_inputs["type"] == "embeds"):
-            pass
-        else:
-            assert_never(prompt_inputs)  # type: ignore[arg-type]
 
         return prompt_inputs
 

vllm/multimodal/processing.py

@@ -1670,15 +1670,17 @@ class BaseMultiModalProcessor(ABC, Generic[_I]):
             placeholders = mm_placeholders.get(modality, [])
 
             if len(placeholders) != item_count:
+                # NOTE: If you are a model developer, this can also arise from
+                # an inconsistency between `_call_hf_processor` and
+                # `_get_mm_fields_config` implementations
                 raise RuntimeError(
                     f"Expected there to be {item_count} prompt updates "
                     f"corresponding to {item_count} {modality} items, but "
                     f"instead found {len(placeholders)} prompt updates! "
-                    "Either the prompt text has missing/incorrect tokens for "
-                    "multi-modal inputs, or there is a problem with your "
-                    "implementation of merged multi-modal processor for this "
-                    "model (usually arising from an inconsistency between "
-                    "`_call_hf_processor` and `_get_prompt_updates`).")
+                    "This is likely because you forgot to include input "
+                    "placeholder tokens (e.g., `<image>`, `<|image_pad|>`) "
+                    "in the prompt. If the model has a chat template, make "
+                    "sure you have applied it before calling `LLM.generate`.")
 
     def _maybe_apply_prompt_updates(
         self,