Adding cpu inference with VXE ISA for s390x architecture (#12613)

Signed-off-by: Dilip Gowda Bhagavan <dilip.bhagavan@ibm.com>
Signed-off-by: Rishika Kedia <rishika.kedia@in.ibm.com>
Co-authored-by: Rishika Kedia <rishika.kedia@in.ibm.com>

Dockerfile.s390x

+# Base UBI image for s390x architecture
+ARG BASE_UBI_IMAGE_TAG=9.5-1736404155
+ARG PYTHON_VERSION=3.12
+FROM registry.access.redhat.com/ubi9/ubi-minimal:${BASE_UBI_IMAGE_TAG} AS base
+
+# Install basic dependencies
+ARG PYTHON_VERSION
+ENV PYTHON_VERSION=${PYTHON_VERSION}
+
+WORKDIR /workspace
+
+ENV LANG=C.UTF-8 \
+    LC_ALL=C.UTF-8
+
+# Install development utilities
+RUN microdnf install -y \
+    which procps findutils tar vim git gcc gcc-gfortran g++ make patch zlib-devel \
+    libjpeg-turbo-devel libtiff-devel libpng-devel libwebp-devel freetype-devel harfbuzz-devel \
+    openssl-devel openblas openblas-devel autoconf automake libtool cmake && \
+    microdnf clean all
+
+# Python Installation
+FROM base AS python-install
+ARG PYTHON_VERSION
+
+ENV VIRTUAL_ENV=/opt/vllm
+ENV PATH="$VIRTUAL_ENV/bin:$PATH"
+ENV PYTHON_VERSION=${PYTHON_VERSION}
+RUN microdnf install -y \
+    python${PYTHON_VERSION}-devel python${PYTHON_VERSION}-pip python${PYTHON_VERSION}-wheel  && \
+    python${PYTHON_VERSION} -m venv $VIRTUAL_ENV && pip install --no-cache -U pip wheel uv && microdnf clean all
+
+FROM python-install AS pyarrow
+
+# Build Apache Arrow
+WORKDIR /tmp
+RUN --mount=type=cache,target=/root/.cache/uv \
+    git clone https://github.com/apache/arrow.git && \
+    cd arrow/cpp && \
+    mkdir release && cd release && \
+    cmake -DCMAKE_BUILD_TYPE=Release \
+          -DCMAKE_INSTALL_PREFIX=/usr/local \
+          -DARROW_PYTHON=ON \
+          -DARROW_PARQUET=ON \
+          -DARROW_ORC=ON \
+          -DARROW_FILESYSTEM=ON \
+          -DARROW_WITH_LZ4=ON \
+          -DARROW_WITH_ZSTD=ON \
+          -DARROW_WITH_SNAPPY=ON \
+          -DARROW_JSON=ON \
+          -DARROW_CSV=ON \
+          -DARROW_DATASET=ON \
+          -DPROTOBUF_PROTOC_EXECUTABLE=/usr/bin/protoc \
+          -DARROW_DEPENDENCY_SOURCE=BUNDLED \
+          .. && \
+    make -j$(nproc) && \
+    make install && \
+    cd ../../python && \
+    export PYARROW_PARALLEL=4 && \
+    export ARROW_BUILD_TYPE=release && \
+    uv pip install -r requirements-build.txt && \
+    python setup.py build_ext --build-type=$ARROW_BUILD_TYPE --bundle-arrow-cpp bdist_wheel
+
+FROM python-install AS numa-build
+# Install numactl (needed for numa.h dependency)
+WORKDIR /tmp
+RUN curl -LO https://github.com/numactl/numactl/archive/refs/tags/v2.0.16.tar.gz && \
+    tar -xvzf v2.0.16.tar.gz && \
+    cd numactl-2.0.16 && \
+    ./autogen.sh && \
+    ./configure && \
+    make
+
+# Set include path
+ENV C_INCLUDE_PATH="/usr/local/include:$C_INCLUDE_PATH"
+
+FROM python-install AS rust
+ENV CARGO_HOME=/root/.cargo
+ENV RUSTUP_HOME=/root/.rustup
+ENV PATH="$CARGO_HOME/bin:$RUSTUP_HOME/bin:$PATH"
+
+RUN curl https://sh.rustup.rs -sSf | sh -s -- -y && \
+    . "$CARGO_HOME/env" && \
+    rustup default stable && \
+    rustup show
+
+FROM python-install AS torch-vision
+# Install torchvision
+ARG TORCH_VERSION=2.7.0.dev20250304
+ARG TORCH_VISION_VERSION=v0.20.1
+WORKDIR /tmp
+RUN --mount=type=cache,target=/root/.cache/uv \
+    git clone https://github.com/pytorch/vision.git && \
+    cd vision && \
+    git checkout $TORCH_VISION_VERSION && \
+    uv pip install -v torch==${TORCH_VERSION} --extra-index-url https://download.pytorch.org/whl/nightly/cpu && \
+    python setup.py bdist_wheel
+
+# Final build stage
+FROM python-install AS vllm-cpu
+ARG PYTHON_VERSION
+
+# Set correct library path for torch and numactl
+ENV LD_LIBRARY_PATH="/opt/vllm/lib64/python${PYTHON_VERSION}/site-packages/torch/lib:/usr/local/lib:$LD_LIBRARY_PATH"
+ENV C_INCLUDE_PATH="/usr/local/include:$C_INCLUDE_PATH"
+ENV UV_LINK_MODE=copy
+ENV CARGO_HOME=/root/.cargo
+ENV RUSTUP_HOME=/root/.rustup
+ENV PATH="$CARGO_HOME/bin:$RUSTUP_HOME/bin:$PATH"
+
+COPY . /workspace/vllm
+WORKDIR /workspace/vllm
+
+RUN --mount=type=bind,from=numa-build,src=/tmp/numactl-2.0.16,target=/numactl \
+    make -C /numactl install
+
+# Install dependencies, including PyTorch and Apache Arrow
+RUN --mount=type=cache,target=/root/.cache/uv \
+    --mount=type=bind,from=rust,source=/root/.cargo,target=/root/.cargo,rw \
+    --mount=type=bind,from=rust,source=/root/.rustup,target=/root/.rustup,rw \
+    --mount=type=bind,from=pyarrow,source=/tmp/arrow/python/dist,target=/tmp/arrow-wheels \
+    --mount=type=bind,from=torch-vision,source=/tmp/vision/dist,target=/tmp/vision-wheels/ \
+     sed -i '/^torch/d' requirements-build.txt && \
+     ARROW_WHL_FILE=$(ls /tmp/arrow-wheels/pyarrow-*.whl | head -n 1) && \
+     VISION_WHL_FILE=$(ls /tmp/vision-wheels/*.whl | head -n 1) && \
+    uv pip install -v \    
+        $ARROW_WHL_FILE  \
+        $VISION_WHL_FILE \
+        --extra-index-url https://download.pytorch.org/whl/nightly/cpu \
+        --index-strategy unsafe-best-match \
+        -r requirements-build.txt \
+        -r requirements-cpu.txt 
+
+# Build and install vllm
+RUN --mount=type=cache,target=/root/.cache/uv \
+    VLLM_TARGET_DEVICE=cpu python setup.py bdist_wheel && \
+    uv pip install "$(echo dist/*.whl)[tensorizer]"
+
+# setup non-root user for vllm
+RUN umask 002 && \
+    useradd --uid 2000 --gid 0 vllm && \
+    mkdir -p /home/vllm && \
+    chmod g+rwx /home/vllm
+
+COPY LICENSE /licenses/vllm.md
+COPY examples/*.jinja /app/data/template/
+
+USER 2000
+WORKDIR /home/vllm
+
+# Set the default entrypoint
+ENTRYPOINT ["python", "-m", "vllm.entrypoints.openai.api_server"]
\ No newline at end of file

cmake/cpu_extension.cmake

@@ -81,6 +81,7 @@ else()
     find_isa(${CPUINFO} "POWER9" POWER9_FOUND)
     find_isa(${CPUINFO} "asimd" ASIMD_FOUND) # Check for ARM NEON support
     find_isa(${CPUINFO} "bf16" ARM_BF16_FOUND) # Check for ARM BF16 support
+    find_isa(${CPUINFO} "S390" S390_FOUND)
 endif()
 
 
@@ -129,8 +130,16 @@ elseif (ASIMD_FOUND)
 elseif(APPLE_SILICON_FOUND)
     message(STATUS "Apple Silicon Detected")
     set(ENABLE_NUMA OFF)
+elseif (S390_FOUND)
+    message(STATUS "S390 detected")
+    # Check for S390 VXE support
+    list(APPEND CXX_COMPILE_FLAGS
+        "-mvx"
+        "-mzvector"
+        "-march=native"
+        "-mtune=native")
 else()
-    message(FATAL_ERROR "vLLM CPU backend requires AVX512, AVX2, Power9+ ISA or ARMv8 support.")
+    message(FATAL_ERROR "vLLM CPU backend requires AVX512, AVX2, Power9+ ISA, S390X ISA or ARMv8 support.")
 endif()
 
 #

csrc/cpu/attention.cpp

@@ -24,8 +24,8 @@ struct KernelVecType<float> {
 
 template <>
 struct KernelVecType<c10::Half> {
-#ifdef __powerpc64__
-  // Power architecture-specific vector types
+#if defined(__powerpc64__) || defined(__s390x__)
+  // Power and s390x architecture-specific vector types
   using q_load_vec_type = vec_op::FP32Vec8;
   using k_load_vec_type = vec_op::FP32Vec16;
   using v_load_vec_type = vec_op::FP32Vec16;

csrc/cpu/cpu_types.hpp

@@ -7,6 +7,9 @@
 #elif defined(__POWER9_VECTOR__)
   // ppc implementation
   #include "cpu_types_vsx.hpp"
+#elif defined(__s390x__)
+  // s390 implementation
+  #include "cpu_types_vxe.hpp"
 #elif defined(__aarch64__)
   // arm implementation
   #include "cpu_types_arm.hpp"

csrc/cpu/cpu_types_vxe.hpp

+
+#ifndef CPU_TYPES_VXE_HPP
+#define CPU_TYPES_VXE_HPP
+
+#include <vecintrin.h>
+#include <cmath>
+#include <torch/all.h>
+namespace vec_op {
+
+#define vec_neg(a) (-(a))
+#define vec_add(a, b) ((a) + (b))
+#define vec_sub(a, b) ((a) - (b))
+#define vec_mul(a, b) ((a) * (b))
+#define vec_div(a, b) ((a) / (b))
+#define vec_sr(a, b) ((a) >> (b))  // Vector Shift Right Algebaic
+#define vec_sl(a, b) ((a) << (b))  // Vector Shift Left
+
+// FIXME: FP16 is not fully supported in Torch-CPU
+#define VLLM_DISPATCH_CASE_FLOATING_TYPES(...)         \
+  AT_DISPATCH_CASE(at::ScalarType::Float, __VA_ARGS__) \
+  AT_DISPATCH_CASE(at::ScalarType::BFloat16, __VA_ARGS__)
+
+#define VLLM_DISPATCH_FLOATING_TYPES(TYPE, NAME, ...) \
+  AT_DISPATCH_SWITCH(TYPE, NAME, VLLM_DISPATCH_CASE_FLOATING_TYPES(__VA_ARGS__))
+
+#ifndef CPU_OP_GUARD
+  #define CPU_KERNEL_GUARD_IN(NAME)
+  #define CPU_KERNEL_GUARD_OUT(NAME)
+#else
+  #define CPU_KERNEL_GUARD_IN(NAME) \
+    std::cout << #NAME << " invoked." << std::endl;
+  #define CPU_KERNEL_GUARD_OUT(NAME) \
+    std::cout << #NAME << " exit." << std::endl;
+#endif
+
+#define FORCE_INLINE __attribute__((always_inline)) inline
+
+namespace {
+template <typename T, T... indexes, typename F>
+constexpr void unroll_loop_item(std::integer_sequence<T, indexes...>, F&& f) {
+  (f(std::integral_constant<T, indexes>{}), ...);
+}
+};  // namespace
+
+template <typename T, T count, typename F,
+          typename = std::enable_if_t<std::is_invocable_v<F, T>>>
+constexpr void unroll_loop(F&& f) {
+  unroll_loop_item(std::make_integer_sequence<T, count>{}, std::forward<F>(f));
+}
+
+template <typename T>
+struct Vec {
+  constexpr static int get_elem_num() { return T::VEC_ELEM_NUM; }
+};
+
+typedef struct ss16x8x2_t {
+  __vector signed short val[2];
+} ss16x8x2_t;
+
+typedef struct ss16x8x4_t {
+  __vector signed short val[4];
+} ss16x8x4_t;
+
+typedef struct f32x4x2_t {
+  __vector float val[2];
+} f32x4x2_t;
+
+typedef struct f32x4x4_t {
+  __vector float val[4];
+} f32x4x4_t;
+
+struct FP32Vec8;
+struct FP32Vec16;
+
+struct BF16Vec8 : public Vec<BF16Vec8> {
+  constexpr static int VEC_ELEM_NUM = 8;
+
+  __vector signed short reg;
+
+  explicit BF16Vec8(const void* ptr) : reg(*(__vector signed short*)ptr) {}
+  explicit BF16Vec8(const FP32Vec8&);
+
+  void save(void* ptr) const {
+    *reinterpret_cast<__vector signed short*>(ptr) = reg;
+  }
+};
+
+struct BF16Vec16 : public Vec<BF16Vec16> {
+  constexpr static int VEC_ELEM_NUM = 16;
+
+  ss16x8x2_t reg;
+
+  explicit BF16Vec16(const void* ptr) {
+    // Load 256 bits in two parts
+    reg.val[0] = (__vector signed short)vec_xl(0, (signed short*)ptr);
+    reg.val[1] = (__vector signed short)vec_xl(16, (signed short*)ptr);
+  }
+
+  explicit BF16Vec16(const FP32Vec16&);
+
+  void save(void* ptr) const {
+    // Save 256 bits in two parts
+    vec_xst(reg.val[0], 0, (signed short*)ptr);
+    vec_xst(reg.val[1], 16, (signed short*)ptr);
+  }
+};
+
+const static __vector signed short zero = vec_splats((signed short)0);
+
+struct BF16Vec32 : public Vec<BF16Vec32> {
+  constexpr static int VEC_ELEM_NUM = 32;
+
+  ss16x8x4_t reg;
+  explicit BF16Vec32(const void* ptr)
+      : reg(*reinterpret_cast<const ss16x8x4_t*>(ptr)) {}
+
+  explicit BF16Vec32(ss16x8x4_t data) : reg(data) {}
+
+  explicit BF16Vec32(const BF16Vec8& vec8_data)
+      : reg({vec8_data.reg, vec8_data.reg, vec8_data.reg, vec8_data.reg}) {}
+
+  void save(void* ptr) const { *reinterpret_cast<ss16x8x4_t*>(ptr) = reg; }
+};
+
+struct FP32Vec4 : public Vec<FP32Vec4> {
+  constexpr static int VEC_ELEM_NUM = 4;
+  union AliasReg {
+    __vector float reg;
+    float values[VEC_ELEM_NUM];
+  };
+
+  __vector float reg;
+
+  explicit FP32Vec4(float v) : reg(vec_splats(v)) {}
+
+  explicit FP32Vec4() : reg(vec_splats(0.0f)) {}
+
+  explicit FP32Vec4(const float* ptr) : reg(vec_xl(0, ptr)) {}
+
+  explicit FP32Vec4(__vector float data) : reg(data) {}
+
+  explicit FP32Vec4(const FP32Vec4& data) : reg(data.reg) {}
+};
+
+struct FP32Vec8 : public Vec<FP32Vec8> {
+  constexpr static int VEC_ELEM_NUM = 8;
+  union AliasReg {
+    f32x4x2_t reg;
+    float values[VEC_ELEM_NUM];
+  };
+
+  f32x4x2_t reg;
+
+  explicit FP32Vec8(float v) {
+    reg.val[0] = vec_splats(v);
+    reg.val[1] = vec_splats(v);
+  }
+
+  explicit FP32Vec8() {
+    reg.val[0] = vec_splats(0.0f);
+    reg.val[1] = vec_splats(0.0f);
+  }
+
+  explicit FP32Vec8(const float* ptr) {
+    reg.val[0] = vec_xl(0, ptr);
+    reg.val[1] = vec_xl(16, ptr);
+  }
+
+  explicit FP32Vec8(f32x4x2_t data) : reg(data) {}
+
+  explicit FP32Vec8(const FP32Vec8& data) {
+    reg.val[0] = data.reg.val[0];
+    reg.val[1] = data.reg.val[1];
+  }
+
+  explicit FP32Vec8(const BF16Vec8& v) {
+    reg.val[0] = (__vector float)vec_mergeh(zero, v.reg);
+    reg.val[1] = (__vector float)vec_mergel(zero, v.reg);
+  }
+
+  float reduce_sum() const {
+    AliasReg ar;
+    ar.reg = reg;
+    float result = 0;
+    unroll_loop<int, VEC_ELEM_NUM>(
+        [&result, &ar](int i) { result += ar.values[i]; });
+
+    return result;
+  }
+
+  FP32Vec8 exp() const {
+    // TODO: Vectorize this
+    AliasReg ar;
+    ar.reg = reg;
+    f32x4x4_t ret;
+    ret.val[0][0] = std::exp(ar.values[0]);
+    ret.val[0][1] = std::exp(ar.values[1]);
+    ret.val[0][2] = std::exp(ar.values[2]);
+    ret.val[0][3] = std::exp(ar.values[3]);
+    ret.val[1][0] = std::exp(ar.values[4]);
+    ret.val[1][1] = std::exp(ar.values[5]);
+    ret.val[1][2] = std::exp(ar.values[6]);
+    ret.val[1][3] = std::exp(ar.values[7]);
+    return FP32Vec8(f32x4x2_t({ret.val[0], ret.val[1]}));
+  }
+
+  FP32Vec8 tanh() const {
+    // TODO: Vectorize this
+    AliasReg ar;
+    ar.reg = reg;
+    f32x4x4_t ret;
+    ret.val[0][0] = std::tanh(ar.values[0]);
+    ret.val[0][1] = std::tanh(ar.values[1]);
+    ret.val[0][2] = std::tanh(ar.values[2]);
+    ret.val[0][3] = std::tanh(ar.values[3]);
+    ret.val[1][0] = std::tanh(ar.values[4]);
+    ret.val[1][1] = std::tanh(ar.values[5]);
+    ret.val[1][2] = std::tanh(ar.values[6]);
+    ret.val[1][3] = std::tanh(ar.values[7]);
+    return FP32Vec8(f32x4x2_t({ret.val[0], ret.val[1]}));
+  }
+
+  FP32Vec8 er() const {
+    // TODO: Vectorize this
+    AliasReg ar;
+    ar.reg = reg;
+    f32x4x4_t ret;
+    ret.val[0][0] = std::erf(ar.values[0]);
+    ret.val[0][1] = std::erf(ar.values[1]);
+    ret.val[0][2] = std::erf(ar.values[2]);
+    ret.val[0][3] = std::erf(ar.values[3]);
+    ret.val[1][0] = std::erf(ar.values[4]);
+    ret.val[1][1] = std::erf(ar.values[5]);
+    ret.val[1][2] = std::erf(ar.values[6]);
+    ret.val[1][3] = std::erf(ar.values[7]);
+    return FP32Vec8(f32x4x2_t({ret.val[0], ret.val[1]}));
+  }
+
+  FP32Vec8 operator*(const FP32Vec8& b) const {
+    return FP32Vec8(
+        {vec_mul(reg.val[0], b.reg.val[0]), vec_mul(reg.val[1], b.reg.val[1])});
+  }
+
+  FP32Vec8 operator+(const FP32Vec8& b) const {
+    return FP32Vec8(
+        {vec_add(reg.val[0], b.reg.val[0]), vec_add(reg.val[1], b.reg.val[1])});
+  }
+
+  FP32Vec8 operator-(const FP32Vec8& b) const {
+    return FP32Vec8(
+        {vec_sub(reg.val[0], b.reg.val[0]), vec_sub(reg.val[1], b.reg.val[1])});
+  }
+
+  FP32Vec8 operator/(const FP32Vec8& b) const {
+    return FP32Vec8(
+        {vec_div(reg.val[0], b.reg.val[0]), vec_div(reg.val[1], b.reg.val[1])});
+  }
+
+  void save(float* ptr) const {
+    vec_xst(reg.val[0], 0, ptr);
+    vec_xst(reg.val[1], 16, ptr);
+  }
+};
+
+struct FP32Vec16 : public Vec<FP32Vec16> {
+  constexpr static int VEC_ELEM_NUM = 16;
+  union AliasReg {
+    f32x4x4_t reg;
+    float values[VEC_ELEM_NUM];
+  };
+
+  f32x4x4_t reg;
+
+  explicit FP32Vec16(float v) {
+    reg.val[0] = vec_splats(v);
+    reg.val[1] = vec_splats(v);
+    reg.val[2] = vec_splats(v);
+    reg.val[3] = vec_splats(v);
+  }
+
+  explicit FP32Vec16() {
+    reg.val[0] = vec_splats(0.0f);
+    reg.val[1] = vec_splats(0.0f);
+    reg.val[2] = vec_splats(0.0f);
+    reg.val[3] = vec_splats(0.0f);
+  }
+
+  explicit FP32Vec16(const float* ptr) {
+    reg.val[0] = vec_xl(0, ptr);
+    reg.val[1] = vec_xl(16, ptr);
+    reg.val[2] = vec_xl(32, ptr);
+    reg.val[3] = vec_xl(48, ptr);
+  }
+
+  explicit FP32Vec16(f32x4x4_t data) : reg(data) {}
+
+  explicit FP32Vec16(const FP32Vec16& data) {
+    reg.val[0] = data.reg.val[0];
+    reg.val[1] = data.reg.val[1];
+    reg.val[2] = data.reg.val[2];
+    reg.val[3] = data.reg.val[3];
+  }
+
+  explicit FP32Vec16(const FP32Vec4& data) {
+    reg.val[0] = data.reg;
+    reg.val[1] = data.reg;
+    reg.val[2] = data.reg;
+    reg.val[3] = data.reg;
+  }
+
+  explicit FP32Vec16(const FP32Vec8& data) {
+    reg.val[0] = data.reg.val[0];
+    reg.val[1] = data.reg.val[1];
+    reg.val[2] = data.reg.val[0];
+    reg.val[3] = data.reg.val[1];
+  }
+
+  explicit FP32Vec16(const BF16Vec16& v) {
+    reg.val[0] = (__vector float)vec_mergeh(zero, v.reg.val[0]);
+    reg.val[1] = (__vector float)vec_mergel(zero, v.reg.val[0]);
+    reg.val[2] = (__vector float)vec_mergeh(zero, v.reg.val[1]);
+    reg.val[3] = (__vector float)vec_mergel(zero, v.reg.val[1]);
+  }
+
+  explicit FP32Vec16(const BF16Vec8& v) : FP32Vec16(FP32Vec8(v)) {}
+
+  FP32Vec16 operator*(const FP32Vec16& b) const {
+    return FP32Vec16(f32x4x4_t({vec_mul(reg.val[0], b.reg.val[0]),
+                                vec_mul(reg.val[1], b.reg.val[1]),
+                                vec_mul(reg.val[2], b.reg.val[2]),
+                                vec_mul(reg.val[3], b.reg.val[3])}));
+  }
+
+  FP32Vec16 operator+(const FP32Vec16& b) const {
+    return FP32Vec16(f32x4x4_t({vec_add(reg.val[0], b.reg.val[0]),
+                                vec_add(reg.val[1], b.reg.val[1]),
+                                vec_add(reg.val[2], b.reg.val[2]),
+                                vec_add(reg.val[3], b.reg.val[3])}));
+  }
+
+  FP32Vec16 operator-(const FP32Vec16& b) const {
+    return FP32Vec16(f32x4x4_t({vec_sub(reg.val[0], b.reg.val[0]),
+                                vec_sub(reg.val[1], b.reg.val[1]),
+                                vec_sub(reg.val[2], b.reg.val[2]),
+                                vec_sub(reg.val[3], b.reg.val[3])}));
+  }
+
+  FP32Vec16 operator/(const FP32Vec16& b) const {
+    return FP32Vec16(f32x4x4_t({vec_div(reg.val[0], b.reg.val[0]),
+                                vec_div(reg.val[1], b.reg.val[1]),
+                                vec_div(reg.val[2], b.reg.val[2]),
+                                vec_div(reg.val[3], b.reg.val[3])}));
+  }
+
+  float reduce_sum() const {
+    AliasReg ar;
+    ar.reg = reg;
+    float result = 0;
+    unroll_loop<int, VEC_ELEM_NUM>(
+        [&result, &ar](int i) { result += ar.values[i]; });
+
+    return result;
+  }
+
+  template <int group_size>
+  float reduce_sub_sum(int idx) {
+    static_assert(VEC_ELEM_NUM % group_size == 0);
+
+    AliasReg ar;
+    ar.reg = reg;
+    float result = 0;
+    const int start = idx * group_size;
+    unroll_loop<int, group_size>(
+        [&result, &start, ar](int i) { result += ar.values[start + i]; });
+
+    return result;
+  }
+
+  void save(float* ptr) const {
+    vec_xst(reg.val[0], 0, ptr);
+    vec_xst(reg.val[1], 16, ptr);
+    vec_xst(reg.val[2], 32, ptr);
+    vec_xst(reg.val[3], 48, ptr);
+  }
+};
+
+template <typename T>
+struct VecType {
+  using vec_type = void;
+};
+
+template <typename T>
+using vec_t = typename VecType<T>::vec_type;
+
+template <>
+struct VecType<float> {
+  using vec_type = FP32Vec8;
+};
+
+template <>
+struct VecType<c10::BFloat16> {
+  using vec_type = BF16Vec8;
+};
+
+template <typename T>
+void storeFP32(float v, T* ptr) {
+  *ptr = v;
+}
+
+inline void fma(FP32Vec16& acc, FP32Vec16& a, FP32Vec16& b) {
+  acc = acc + a * b;
+}
+
+namespace c10 {
+struct BFloat16 {
+  uint16_t value;  // Assume BFloat16 is defined as a struct containing a 16-bit
+                   // value.
+};
+}  // namespace c10
+
+template <>
+inline void storeFP32<c10::BFloat16>(float v, c10::BFloat16* ptr) {
+  c10::BFloat16 __attribute__((__may_alias__))* v_ptr =
+      reinterpret_cast<c10::BFloat16*>(&v);
+  *ptr = *(v_ptr + 1);
+}
+
+#ifndef __VEC_CLASS_FP_NAN
+  #define __VEC_CLASS_FP_NAN (1 << 6)
+#endif
+
+const static __vector unsigned char omask = {2,  3,  6,  7,  10, 11, 14, 15,
+                                             18, 19, 22, 23, 26, 27, 30, 31};
+const static __vector unsigned int bias = {0x00007fff, 0x00007fff, 0x00007fff,
+                                           0x00007fff};
+const static __vector unsigned int nan = {0x7fc00000, 0x7fc00000, 0x7fc00000,
+                                          0x7fc00000};
+const static __vector unsigned int sh16 = {16, 16, 16, 16};
+const static __vector unsigned int one = {1, 1, 1, 1};
+
+inline BF16Vec8::BF16Vec8(const FP32Vec8& v) {
+  __vector unsigned int inp0 = (__vector unsigned int)(v.reg.val[0]);
+  __vector unsigned int inp1 = (__vector unsigned int)(v.reg.val[1]);
+  int cc;
+  __vector __bool int sel0 =
+      vec_fp_test_data_class(v.reg.val[0], __VEC_CLASS_FP_NAN, &cc);
+  __vector __bool int sel1 =
+      vec_fp_test_data_class(v.reg.val[1], __VEC_CLASS_FP_NAN, &cc);
+  inp0 = vec_sel(inp0, nan, sel0) >> sh16;
+  inp1 = vec_sel(inp1, nan, sel1) >> sh16;
+  reg = (__vector signed short)vec_perm(inp0, inp1, omask);
+}
+
+inline BF16Vec16::BF16Vec16(const FP32Vec16& v) {
+  __vector unsigned int inp0 = (__vector unsigned int)(v.reg.val[0]);
+  __vector unsigned int inp1 = (__vector unsigned int)(v.reg.val[1]);
+  __vector unsigned int inp2 = (__vector unsigned int)(v.reg.val[2]);
+  __vector unsigned int inp3 = (__vector unsigned int)(v.reg.val[3]);
+  int cc;
+  __vector __bool int sel0 =
+      vec_fp_test_data_class(v.reg.val[0], __VEC_CLASS_FP_NAN, &cc);
+  __vector __bool int sel1 =
+      vec_fp_test_data_class(v.reg.val[1], __VEC_CLASS_FP_NAN, &cc);
+  __vector __bool int sel2 =
+      vec_fp_test_data_class(v.reg.val[2], __VEC_CLASS_FP_NAN, &cc);
+  __vector __bool int sel3 =
+      vec_fp_test_data_class(v.reg.val[3], __VEC_CLASS_FP_NAN, &cc);
+  inp0 = vec_sel(inp0, nan, sel0) >> sh16;
+  inp1 = vec_sel(inp1, nan, sel1) >> sh16;
+  inp2 = vec_sel(inp2, nan, sel2) >> sh16;
+  inp3 = vec_sel(inp3, nan, sel3) >> sh16;
+  reg.val[0] = (__vector signed short)vec_perm(inp0, inp1, omask);
+  reg.val[1] = (__vector signed short)vec_perm(inp2, inp3, omask);
+}
+
+inline void prefetch(const void* addr) { void __dcbt(const void* addr); }
+
+};  // namespace vec_op
+
+#endif
\ No newline at end of file

csrc/cpu/quant.cpp

@@ -25,7 +25,7 @@ struct KernelVecType<c10::BFloat16> {
 
 template <>
 struct KernelVecType<c10::Half> {
-#ifdef __powerpc64__
+#if defined(__powerpc64__) || defined(__s390x__)
   // Power architecture-specific vector type
   using load_vec_type = vec_op::FP32Vec16;
 #else

requirements-cpu.txt

@@ -2,14 +2,15 @@
 -r requirements-common.txt
 
 # Dependencies for CPUs
-torch==2.5.1+cpu; platform_machine != "ppc64le" and platform_machine != "aarch64" and platform_system != "Darwin"
-torch==2.5.1; platform_machine == "ppc64le" or platform_machine == "aarch64" or platform_system == "Darwin" 
+torch==2.5.1+cpu; platform_machine != "ppc64le" and platform_machine != "aarch64" and platform_system != "Darwin" and platform_machine != "s390x"
+torch==2.5.1; platform_machine == "ppc64le" or platform_machine == "aarch64" or platform_system == "Darwin"
+torch==2.7.0.dev20250304; platform_machine == "s390x"
 
 # required for the image processor of minicpm-o-2_6, this must be updated alongside torch
-torchaudio; platform_machine != "ppc64le"
+torchaudio; platform_machine != "ppc64le" and platform_machine != "s390x"
 torchaudio==2.5.1; platform_machine == "ppc64le"
 
 # required for the image processor of phi3v, this must be updated alongside torch
-torchvision; platform_machine != "ppc64le"
+torchvision; platform_machine != "ppc64le"  and platform_machine != "s390x"
 torchvision==0.20.1; platform_machine == "ppc64le"
 datasets # for benchmark scripts