vllm.compilation.passes.fusion.rocm_aiter_fusion ¶

class AddAiterRMSNormPadPattern:
    """
    This pattern replaces an aiter_rmsnorm_with_add & a pad op
    with a custom triton_add_rmsnorm_pad op from AITER.
    """

    AITER_TRITON_ADD_RMSNORM_PAD_OP = rocm_aiter_ops.get_triton_add_rmsnorm_pad_op()

    def __init__(
        self,
        epsilon: float,
        hidden_size: int,
        x_pad_to_multiple: int,
    ):
        self.epsilon = epsilon
        self.hidden_size = hidden_size
        self.x_pad_to_multiple = x_pad_to_multiple
        self.rmsnorm_matcher = MatcherFusedAddRMSNorm(epsilon, match_rocm_aiter=True)

    def get_inputs(self) -> list[torch.Tensor]:
        input, weight, residual = self.rmsnorm_matcher.inputs()
        router_weight = torch.empty([8, 16], dtype=weight.dtype, device=weight.device)
        router_bias = torch.empty([8], dtype=weight.dtype, device=weight.device)
        return [input, weight, residual, router_weight, router_bias]

    def register(self, pm_pass: PatternMatcherPass) -> None:
        def pattern(
            input: torch.Tensor,
            weight: torch.Tensor,
            residual: torch.Tensor,
            router_weight: torch.Tensor,
            router_bias: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
            pad_size = self.x_pad_to_multiple - (
                self.hidden_size % self.x_pad_to_multiple
            )
            result_rms, residual_out = self.rmsnorm_matcher(input, weight, residual)
            router_logits = torch.ops.vllm.rocm_unquantized_gemm(
                result_rms, router_weight, router_bias
            )
            result = torch.nn.functional.pad(
                result_rms, (0, pad_size), mode="constant", value=0.0
            )
            return result, residual_out, router_logits

        def replacement(
            input: torch.Tensor,
            weight: torch.Tensor,
            residual: torch.Tensor,
            router_weight: torch.Tensor,
            router_bias: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
            at = self.AITER_TRITON_ADD_RMSNORM_PAD_OP(
                x=input,
                weight=weight,
                variance_epsilon=self.epsilon,
                residual=residual,
                x_pad_to_multiple=self.x_pad_to_multiple,
            )
            result_padded = at[0]
            router_logits = torch.ops.vllm.rocm_unquantized_gemm(
                result_padded[:, : self.hidden_size], router_weight, router_bias
            )
            residual_out = at[1]
            return result_padded, residual_out, router_logits

        pm.register_replacement(
            pattern, replacement, self.get_inputs(), pm.fwd_only, pm_pass
        )

class AiterFusedAddRMSFp8GroupQuantPattern(AiterRMSNormQuantPattern):
    """
    This pattern fuses aiter rms_norm_with_add & group fp8 quant custom ops
    into a aiter rms_norm_with_add_group_fp8_quant op.
    """

    FUSED_OP = rocm_aiter_ops.get_rmsnorm_group_add_fused_quant_op()

    def __init__(
        self,
        epsilon: float,
        quant_dtype: torch.dtype,
        group_shape: GroupShape,
        match_aiter_quant: bool = True,
        symmetric: bool = True,
    ) -> None:
        scale = ScaleDesc(torch.float32, False, group_shape)
        key = FusedRMSQuantKey(
            fused_add=True,
            quant=QuantKey(dtype=quant_dtype, scale=scale, symmetric=symmetric),
        )

        super().__init__(epsilon, key, match_aiter_quant)

    def register(self, pm_pass: PatternMatcherPass) -> None:
        def pattern(
            input: torch.Tensor,
            weight: torch.Tensor,
            residual: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
            result_rms, residual_out = self.rmsnorm_matcher(input, weight, residual)
            result, scale = self.quant_matcher(result_rms)

            return result, residual_out, scale

        def replacement(
            input: torch.Tensor,
            weight: torch.Tensor,
            residual: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
            at = self.FUSED_OP(
                x=input,
                residual=residual,
                weight=weight,
                variance_epsilon=self.epsilon,
                group_size=128,
            )

            # result, scale, residual
            return at[0], at[1], at[2]

        pm.register_replacement(
            pattern, replacement, self.rmsnorm_matcher.inputs(), pm.fwd_only, pm_pass
        )

class AiterFusedAddRMSNormDynamicQuantPattern(AiterRMSNormQuantPattern):
    """AITER RMSNorm Fused Add + Dynamic Quantization pattern."""

    FUSED_OP = rocm_aiter_ops.get_rmsnorm_fused_add_dynamic_quant_op()

    def __init__(
        self,
        epsilon: float,
        quant_dtype: torch.dtype,
        match_aiter_quant: bool = True,
        group_shape: GroupShape = GroupShape.PER_TOKEN,
        symmetric: bool = True,
    ) -> None:
        scale = ScaleDesc(torch.float32, False, group_shape)
        key = FusedRMSQuantKey(
            fused_add=True,
            quant=QuantKey(dtype=quant_dtype, scale=scale, symmetric=symmetric),
        )

        super().__init__(epsilon, key, match_aiter_quant)

    def register(self, pm_pass: PatternMatcherPass) -> None:
        def pattern(
            input: torch.Tensor,
            weight: torch.Tensor,
            residual: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
            result_rms, residual_out = self.rmsnorm_matcher(input, weight, residual)
            result, scale = self.quant_matcher(result_rms)

            return result, residual_out, scale

        def replacement(
            input: torch.Tensor, weight: torch.Tensor, residual: torch.Tensor
        ) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
            result = self.FUSED_OP(
                x=input,
                residual=residual,
                weight=weight,
                epsilon=self.epsilon,
                quant_dtype=self.quant_dtype,
            )

            return result[0], result[1], result[2]

        pm.register_replacement(
            pattern,
            replacement,
            self.rmsnorm_matcher.inputs(),
            pm.fwd_only,
            pm_pass,
        )

class AiterRMSFp8GroupQuantPattern(AiterRMSNormQuantPattern):
    """
    This pattern fuses aiter rms_norm & group fp8 quant custom
    ops into an aiter rms_norm_group_fp8_quant op.
    """

    FUSED_OP = rocm_aiter_ops.get_rmsnorm_group_fused_quant_op()

    def __init__(
        self,
        epsilon: float,
        quant_dtype: torch.dtype,
        group_shape: GroupShape,
        match_aiter_quant: bool = True,
        symmetric: bool = True,
    ) -> None:
        scale = ScaleDesc(torch.float32, False, group_shape)
        key = FusedRMSQuantKey(
            fused_add=False,
            quant=QuantKey(dtype=quant_dtype, scale=scale, symmetric=symmetric),
        )

        super().__init__(epsilon, key, match_aiter_quant)

    def register(self, pm_pass: PatternMatcherPass) -> None:
        def pattern(
            input: torch.Tensor,
            weight: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor]:
            result_rms = torch.ops.vllm_ir.rms_norm(input, weight, self.epsilon)
            result, scale = self.quant_matcher(result_rms)
            return result, scale

        def replacement(
            input: torch.Tensor,
            weight: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor]:
            at = self.FUSED_OP(
                x=input,
                weight=weight,
                variance_epsilon=self.epsilon,
                group_size=128,
            )

            return at[0], at[1]

        pm.register_replacement(
            pattern,
            replacement,
            # input, weight
            [self.empty(5, 16), self.empty(16)],
            pm.fwd_only,
            pm_pass,
        )

class AiterRMSNormDynamicQuantPattern(AiterRMSNormQuantPattern):
    """AITER RMSNorm + Dynamic Quantization pattern."""

    FUSED_OP = rocm_aiter_ops.get_rmsnorm_fused_dynamic_quant_op()

    def __init__(
        self,
        epsilon: float,
        quant_dtype: torch.dtype,
        match_aiter_quant: bool = True,
        group_shape: GroupShape = GroupShape.PER_TOKEN,
        symmetric: bool = True,
    ) -> None:
        scale = ScaleDesc(torch.float32, False, group_shape)
        key = FusedRMSQuantKey(
            fused_add=False,
            quant=QuantKey(dtype=quant_dtype, scale=scale, symmetric=symmetric),
        )

        super().__init__(epsilon, key, match_aiter_quant)

    def register(self, pm_pass: PatternMatcherPass) -> None:
        def pattern(
            input: torch.Tensor,
            weight: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor]:
            result_rms = torch.ops.vllm_ir.rms_norm(input, weight, self.epsilon)
            result, scale = self.quant_matcher(result_rms)
            return result, scale

        def replacement(
            input: torch.Tensor,
            weight: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor]:
            result = self.FUSED_OP(
                x=input,
                weight=weight,
                epsilon=self.epsilon,
                quant_dtype=self.quant_dtype,
            )

            return result[0], result[1]

        pm.register_replacement(
            pattern,
            replacement,
            # input, weight
            [self.empty(5, 16), self.empty(16)],
            pm.fwd_only,
            pm_pass,
        )

class AiterSiluMulFp8GroupQuantPattern(VllmPatternReplacement):
    """
    This pattern fuses aiter silu_and_mul & group fp8 quant custom
    ops into an aiter silu_and_mul_group_fp8_quant op.
    """

    FUSED_SILU_MUL_QUANT_OP = rocm_aiter_ops.get_act_mul_fused_fp8_group_quant_op()

    def __init__(self) -> None:
        self.silu_and_mul_matcher = MatcherSiluAndMul()
        self.quant_matcher = MatcherQuantFP8(
            quant_key=kFp8Dynamic128Sym, match_rocm_aiter=True
        )

    def get_inputs(self) -> list[torch.Tensor]:
        return [
            self.silu_and_mul_matcher.inputs()[0],
        ]

    @property
    def pattern(self):
        def _pattern(
            input: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor]:
            at1 = self.silu_and_mul_matcher(input)
            at2 = self.quant_matcher(at1)
            return at2[0], at2[1]

        return _pattern

    @property
    def replacement(self):
        def _replacement(
            input: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor]:
            at = self.FUSED_SILU_MUL_QUANT_OP(x=input, group_size=128)
            return at[0], at[1]

        return _replacement

class MLADualRMSNormFusionPass(VllmFusionPatternMatcherPass):
    """
    Post-grad PatternMatcher pass that fuses paired q / kv RMS norms in
    MLA attention into ``fused_mla_dual_rms_norm`` backed by aiter's
    ``fused_qk_rmsnorm`` HIP kernel.
    """

    def __init__(self, config: VllmConfig) -> None:
        super().__init__(config, "mla_dual_rms_norm_fusion_pass")

        for epsilon in [1e-5, 1e-6]:
            self.register(MLADualRMSNormPattern(epsilon))

class MLADualRMSNormPattern(
    VllmPatternReplacement[..., tuple[torch.Tensor, torch.Tensor, torch.Tensor]]
):
    """
    Fuse paired q_a_layernorm + kv_a_layernorm in MLA attention into
    AITER's ``fused_qk_rmsnorm`` HIP kernel.

    Target FX-graph pattern (unfused, ``vllm_ir`` stage)::

        gemm -> split_with_sizes([q_dim, kv_dim])
            +-- q_c     -> vllm_ir.rms_norm(q_c, q_w, eps)
            +-- kv_lora -> split_with_sizes([kv_c_dim, k_pe_dim])
                            +-- kv_c -> vllm_ir.rms_norm(kv_c, kv_w, eps)
                            +-- k_pe

    The pattern covers the connected subgraph rooted at the first
    ``split_with_sizes`` (which produces ``q_c`` and ``kv_lora``),
    through the two ``rms_norm`` calls, and the ``k_pe`` passthrough.
    """

    def __init__(self, epsilon: float) -> None:
        self._epsilon = epsilon

    def get_inputs(self) -> list[torch.Tensor]:
        q_dim, kv_c_dim, k_pe_dim = 8, 4, 2
        return [
            self.empty_bf16(5, q_dim + kv_c_dim + k_pe_dim),
            self.empty_bf16(q_dim),
            self.empty_bf16(kv_c_dim),
        ]

    @property
    def pattern(
        self,
    ) -> Callable[..., tuple[torch.Tensor, torch.Tensor, torch.Tensor]]:
        eps = self._epsilon

        def _pattern(
            projected: torch.Tensor,
            q_weight: torch.Tensor,
            kv_weight: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
            q_dim = q_weight.shape[0]
            kv_dim = projected.shape[-1] - q_dim
            kv_c_dim = kv_weight.shape[0]
            k_pe_dim = kv_dim - kv_c_dim
            q_c, kv_lora = projected.split([q_dim, kv_dim], dim=-1)
            kv_c, k_pe = kv_lora.split([kv_c_dim, k_pe_dim], dim=-1)
            q_normed = vllm.ir.ops.rms_norm(q_c, q_weight, eps)
            kv_normed = vllm.ir.ops.rms_norm(kv_c, kv_weight, eps)
            return q_normed, kv_normed, k_pe

        return _pattern

    @property
    def replacement(
        self,
    ) -> Callable[..., tuple[torch.Tensor, torch.Tensor, torch.Tensor]]:
        eps = self._epsilon

        def _replacement(
            projected: torch.Tensor,
            q_weight: torch.Tensor,
            kv_weight: torch.Tensor,
        ) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
            q_dim = q_weight.shape[0]
            kv_dim = projected.shape[-1] - q_dim
            kv_c_dim = kv_weight.shape[0]
            k_pe_dim = kv_dim - kv_c_dim
            q_c, kv_lora = projected.split([q_dim, kv_dim], dim=-1)
            kv_c, k_pe = kv_lora.split([kv_c_dim, k_pe_dim], dim=-1)
            q_normed, kv_normed = torch.ops.vllm.fused_mla_dual_rms_norm(
                q_c,
                q_weight,
                kv_c,
                kv_weight,
                eps,
                eps,
            )
            return q_normed, kv_normed, k_pe

        return _replacement

class RocmAiterRMSNormQuantFusionPass(VllmPatternMatcherPass):
    """
    This pass fuses aiter rms_norm & vllm/aiter quant custom ops
    into a fused rms_norm_quant op.
    It also supports fused_add_rms_norm.
    """

    @enable_fake_mode
    def __init__(self, config: VllmConfig) -> None:
        super().__init__(config)

        self.patterns: PatternMatcherPass = PatternMatcherPass(
            pass_name="rocm_aiter_rms_norm_quant_fusion_pass"
        )

        # Make sure fused add patterns are before simple rms norm,
        # as the latter is a subset of the former in torch ops
        for epsilon in [1e-5, 1e-6]:
            #  Fuse aiter rms_norm + aiter dynamic group fp8 quant
            AiterRMSFp8GroupQuantPattern(
                epsilon, FP8_DTYPE, GroupShape(1, 128)
            ).register(self.patterns)

            # Fuse aiter fused_add_rms_norm + aiter dynamic group fp8 quant
            AiterFusedAddRMSFp8GroupQuantPattern(
                epsilon, FP8_DTYPE, GroupShape(1, 128)
            ).register(self.patterns)

            for match_aiter_quant in [True, False]:
                # Fuse aiter rms_norm + (aiter / vllm built-in)
                # dynamic per-token fp8 quant
                AiterRMSNormDynamicQuantPattern(
                    epsilon, FP8_DTYPE, match_aiter_quant=match_aiter_quant
                ).register(self.patterns)

                # Fuse aiter fused_add_rms_norm + (aiter / vllm built-in)
                # dynamic per-token fp8 quant
                AiterFusedAddRMSNormDynamicQuantPattern(
                    epsilon, FP8_DTYPE, match_aiter_quant=match_aiter_quant
                ).register(self.patterns)

        self.dump_patterns(config, self.patterns)

    @VllmInductorPass.time_and_log
    def __call__(self, graph: fx.Graph) -> None:
        self.matched_count = self.patterns.apply(graph)
        logger.debug(
            "%s Replaced %s patterns", self.__class__.__name__, self.matched_count
        )

    def uuid(self) -> str:
        fusion_patterns = [
            AiterRMSNormDynamicQuantPattern,
            AiterFusedAddRMSNormDynamicQuantPattern,
            AiterRMSFp8GroupQuantPattern,
            AiterFusedAddRMSFp8GroupQuantPattern,
        ]
        return self.hash_source(self, *fusion_patterns)

class RocmAiterSiluMulFp8GroupQuantFusionPass(VllmFusionPatternMatcherPass):
    """
    This pass fuses a pre-defined set of custom ops into fused ops.
    It uses the torch pattern matcher to find the patterns and replace them.

    Because patterns can only be registered once, the pass is a singleton.
    This will be addressed in a future version of PyTorch:
    https://github.com/pytorch/pytorch/pull/139321#issuecomment-2452354980
    """

    def __init__(self, config: VllmConfig) -> None:
        super().__init__(config, "rocm_aiter_silu_mul_fp8_group_quant_fusion_pass")

        self.register(AiterSiluMulFp8GroupQuantPattern())

        self.dump_patterns(config, self.pm_pass)

class RocmAiterTritonAddRMSNormPadFusionPass(VllmPatternMatcherPass):
    """
    This pass replaces an AITER CK RMSNorm + residual add and a pad op
    with an triton_add_rmsnorm_pad op from AITER.
    """

    def __init__(self, config: VllmConfig):
        super().__init__(config)
        self.patterns: PatternMatcherPass = PatternMatcherPass(
            pass_name="rocm_aiter_triton_add_rmsnorm_pad_fusion_pass"
        )

        # gpt-oss has hidden size 2880
        # padded to a multiple of 128 on gfx942 and 256 on gfx950 respectively
        hidden_size = 2880
        for epsilon in [1e-5, 1e-6]:
            for x_pad_to_multiple in [128, 256]:
                AddAiterRMSNormPadPattern(
                    epsilon, hidden_size, x_pad_to_multiple
                ).register(self.patterns)

        self.dump_patterns(config, self.patterns)

    @VllmInductorPass.time_and_log
    def __call__(self, graph: torch.fx.Graph) -> None:
        self.matched_count = self.patterns.apply(graph)
        logger.debug("Replaced %s patterns", self.matched_count)

    def uuid(self) -> str:
        return VllmInductorPass.hash_source(self, AddAiterRMSNormPadPattern)