vllm/csrc/moe/marlin_moe_wna16/marlin_template.h
Jinzhen Lin d06ba4ed3f
[Kernel] moe wna16 marlin kernel (#14447)
Signed-off-by: Jinzhen Lin <linjinzhen@hotmail.com>
Co-authored-by: Michael Goin <michael@neuralmagic.com>
Co-authored-by: mgoin <mgoin64@gmail.com>
2025-04-14 20:05:22 -07:00

1918 lines
73 KiB
C++

/*
* Modified by Neural Magic
* Copyright (C) Marlin.2024 Elias Frantar
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* Adapted from https://github.com/IST-DASLab/marlin
*/
#ifndef MARLIN_NAMESPACE_NAME
#define MARLIN_NAMESPACE_NAME marlin_moe_wna16
#endif
#include "quantization/gptq_marlin/marlin.cuh"
#include "quantization/gptq_marlin/marlin_dtypes.cuh"
#include "core/scalar_type.hpp"
#define STATIC_ASSERT_SCALAR_TYPE_VALID(scalar_t) \
static_assert(std::is_same<scalar_t, half>::value || \
std::is_same<scalar_t, nv_bfloat16>::value, \
"only float16 and bfloat16 is supported");
namespace MARLIN_NAMESPACE_NAME {
#if defined(__CUDA_ARCH__) && __CUDA_ARCH__ < 800
template <typename scalar_t, // compute dtype, half or nv_float16
const vllm::ScalarTypeId w_type_id, // weight ScalarType id
const int threads, // number of threads in a threadblock
const int thread_m_blocks, // number of 16x16 blocks in the m
// dimension (batchsize) of the
// threadblock
const int thread_n_blocks, // same for n dimension (output)
const int thread_k_blocks, // same for k dimension (reduction)
const bool m_block_size_8, // whether m_block_size == 8
// only works when thread_m_blocks == 1
const int stages, // number of stages for the async global->shared
// fetch pipeline
const bool has_act_order, // whether act_order is enabled
const bool has_zp, // whether zero-points are enabled
const int group_blocks, // number of consecutive 16x16 blocks
// with a separate quantization scale
const bool is_zp_float // is zero point of float16 type?
>
__global__ void Marlin(
const int4* __restrict__ A, // fp16 input matrix of shape mxk
const int4* __restrict__ B, // 4bit quantized weight matrix of shape kxn
int4* __restrict__ C, // fp16 output buffer of shape mxn
int4* __restrict__ C_tmp, // fp32 tmp output buffer (for reduce)
const int4* __restrict__ scales_ptr, // fp16 quantization scales of shape
// (k/groupsize)xn
const int4* __restrict__ zp_ptr, // 4bit packed zero-points of shape
// (k/groupsize)x(n/pack_factor)
const int* __restrict__ g_idx, // int32 group indices of shape k
const int32_t* __restrict__ sorted_token_ids_ptr, // moe sorted_ids
const int32_t* __restrict__ expert_ids_ptr, // moe expert ids
const int32_t* __restrict__ num_tokens_past_padded_ptr, // moe num tokens
const float* __restrict__ topk_weights_ptr, // moe top weights
int top_k, // num of experts per token
bool mul_topk_weights, // mul topk weights or not
bool is_ep, // expert parallelism
int num_groups, // number of scale groups per output channel
int prob_m, // batch dimension m
int prob_n, // output dimension n
int prob_k, // reduction dimension k
int* locks, // extra global storage for barrier synchronization
bool use_atomic_add, // whether to use atomic add to reduce
bool use_fp32_reduce // whether to use fp32 global reduce
) {}
} // namespace MARLIN_NAMESPACE_NAME
#else
// m16n8k16 tensor core mma instruction with fp16 inputs and fp32
// output/accumulation.
template <typename scalar_t>
__device__ inline void mma(const typename ScalarType<scalar_t>::FragA& a_frag,
const typename ScalarType<scalar_t>::FragB& frag_b,
typename ScalarType<scalar_t>::FragC& frag_c) {
const uint32_t* a = reinterpret_cast<const uint32_t*>(&a_frag);
const uint32_t* b = reinterpret_cast<const uint32_t*>(&frag_b);
float* c = reinterpret_cast<float*>(&frag_c);
if constexpr (std::is_same<scalar_t, half>::value) {
asm volatile(
"mma.sync.aligned.m16n8k16.row.col.f32.f16.f16.f32 "
"{%0,%1,%2,%3}, {%4,%5,%6,%7}, {%8,%9}, {%10,%11,%12,%13};\n"
: "=f"(c[0]), "=f"(c[1]), "=f"(c[2]), "=f"(c[3])
: "r"(a[0]), "r"(a[1]), "r"(a[2]), "r"(a[3]), "r"(b[0]), "r"(b[1]),
"f"(c[0]), "f"(c[1]), "f"(c[2]), "f"(c[3]));
} else if constexpr (std::is_same<scalar_t, nv_bfloat16>::value) {
asm volatile(
"mma.sync.aligned.m16n8k16.row.col.f32.bf16.bf16.f32 "
"{%0,%1,%2,%3}, {%4,%5,%6,%7}, {%8,%9}, {%10,%11,%12,%13};\n"
: "=f"(c[0]), "=f"(c[1]), "=f"(c[2]), "=f"(c[3])
: "r"(a[0]), "r"(a[1]), "r"(a[2]), "r"(a[3]), "r"(b[0]), "r"(b[1]),
"f"(c[0]), "f"(c[1]), "f"(c[2]), "f"(c[3]));
} else {
STATIC_ASSERT_SCALAR_TYPE_VALID(scalar_t);
}
}
template <typename scalar_t>
__device__ inline void mma_trans(
const typename ScalarType<scalar_t>::FragA& a_frag,
const typename ScalarType<scalar_t>::FragB& frag_b,
const typename ScalarType<scalar_t>::FragB& frag_b2,
typename ScalarType<scalar_t>::FragC& frag_c) {
const uint32_t* a = reinterpret_cast<const uint32_t*>(&a_frag);
const uint32_t* b = reinterpret_cast<const uint32_t*>(&frag_b);
const uint32_t* b2 = reinterpret_cast<const uint32_t*>(&frag_b2);
float* c = reinterpret_cast<float*>(&frag_c);
if constexpr (std::is_same<scalar_t, half>::value) {
asm volatile(
"mma.sync.aligned.m16n8k16.row.col.f32.f16.f16.f32 "
"{%0,%1,%2,%3}, {%4,%5,%6,%7}, {%8,%9}, {%10,%11,%12,%13};\n"
: "=f"(c[0]), "=f"(c[1]), "=f"(c[2]), "=f"(c[3])
: "r"(b[0]), "r"(b2[0]), "r"(b[1]), "r"(b2[1]), "r"(a[0]), "r"(a[1]),
"f"(c[0]), "f"(c[1]), "f"(c[2]), "f"(c[3]));
} else if constexpr (std::is_same<scalar_t, nv_bfloat16>::value) {
asm volatile(
"mma.sync.aligned.m16n8k16.row.col.f32.bf16.bf16.f32 "
"{%0,%1,%2,%3}, {%4,%5,%6,%7}, {%8,%9}, {%10,%11,%12,%13};\n"
: "=f"(c[0]), "=f"(c[1]), "=f"(c[2]), "=f"(c[3])
: "r"(b[0]), "r"(b2[0]), "r"(b[1]), "r"(b2[1]), "r"(a[0]), "r"(a[1]),
"f"(c[0]), "f"(c[1]), "f"(c[2]), "f"(c[3]));
} else {
STATIC_ASSERT_SCALAR_TYPE_VALID(scalar_t);
}
}
// Instruction for loading a full 16x16 matrix fragment of operand A from shared
// memory, directly in tensor core layout.
template <int count, typename scalar_t>
__device__ inline void ldsm(typename ScalarType<scalar_t>::FragA& frag_a,
const void* smem_ptr) {
uint32_t* a = reinterpret_cast<uint32_t*>(&frag_a);
uint32_t smem = static_cast<uint32_t>(__cvta_generic_to_shared(smem_ptr));
if constexpr (count == 4) {
asm volatile(
"ldmatrix.sync.aligned.m8n8.x4.shared.b16 {%0,%1,%2,%3}, [%4];\n"
: "=r"(a[0]), "=r"(a[1]), "=r"(a[2]), "=r"(a[3])
: "r"(smem));
} else if constexpr (count == 2) {
asm volatile("ldmatrix.sync.aligned.m8n8.x2.shared.b16 {%0,%1}, [%2];\n"
: "=r"(a[0]), "=r"(a[1])
: "r"(smem));
} else if constexpr (count == 1) {
asm volatile("ldmatrix.sync.aligned.m8n8.x1.shared.b16 {%0}, [%1];\n"
: "=r"(a[0])
: "r"(smem));
} else {
static_assert(count == 1 || count == 2 || count == 4, "invalid count");
}
}
// Lookup-table based 3-input logical operation; explicitly used for
// dequantization as the compiler does not seem to automatically recognize it in
// all cases.
template <int lut>
__device__ inline int lop3(int a, int b, int c) {
int res;
asm volatile("lop3.b32 %0, %1, %2, %3, %4;\n"
: "=r"(res)
: "r"(a), "r"(b), "r"(c), "n"(lut));
return res;
}
// Constructs destination register by taking bytes from 2 sources (based on
// mask)
template <int start_byte, int mask>
__device__ inline uint32_t prmt(uint32_t a) {
uint32_t res;
asm volatile("prmt.b32 %0, %1, %2, %3;\n"
: "=r"(res)
: "r"(a), "n"(start_byte), "n"(mask));
return res;
}
template <typename scalar_t, int bit>
__device__ inline typename ScalarType<scalar_t>::FragB dequant(
int q, typename ScalarType<scalar_t>::FragB& frag_b);
//
// Efficiently dequantize 4bit values packed in an int32 value into a full
// B-fragment of 4 fp16 values. We mostly follow the strategy in the link below,
// with some small changes:
// - FP16:
// https://github.com/NVIDIA/FasterTransformer/blob/release/v5.3_tag/src/fastertransformer/cutlass_extensions/include/cutlass_extensions/interleaved_numeric_conversion.h#L215-L287
// - BF16:
// https://github.com/NVIDIA/FasterTransformer/blob/release/v5.3_tag/src/fastertransformer/cutlass_extensions/include/cutlass_extensions/interleaved_numeric_conversion.h#L327-L385
//
template <>
__device__ inline typename ScalarType<half>::FragB dequant<half, 4>(
int q, typename ScalarType<half>::FragB& frag_b) {
const int LO = 0x000f000f;
const int HI = 0x00f000f0;
const int EX = 0x64006400;
// Guarantee that the `(a & b) | c` operations are LOP3s.
int lo = lop3 < (0xf0 & 0xcc) | 0xaa > (q, LO, EX);
int hi = lop3 < (0xf0 & 0xcc) | 0xaa > (q, HI, EX);
// We want signed int4 outputs, hence we fuse the `-8` symmetric zero point
// directly into `SUB` and `ADD`.
const int SUB = 0x64086408;
const int MUL = 0x2c002c00;
const int ADD = 0xd480d480;
frag_b[0] = __hsub2(*reinterpret_cast<half2*>(&lo),
*reinterpret_cast<const half2*>(&SUB));
frag_b[1] = __hfma2(*reinterpret_cast<half2*>(&hi),
*reinterpret_cast<const half2*>(&MUL),
*reinterpret_cast<const half2*>(&ADD));
return frag_b;
}
template <>
__device__ inline typename ScalarType<nv_bfloat16>::FragB
dequant<nv_bfloat16, 4>(int q,
typename ScalarType<nv_bfloat16>::FragB& frag_b) {
static constexpr uint32_t MASK = 0x000f000f;
static constexpr uint32_t EX = 0x43004300;
// Guarantee that the `(a & b) | c` operations are LOP3s.
int lo = lop3 < (0xf0 & 0xcc) | 0xaa > (q, MASK, EX);
q >>= 4;
int hi = lop3 < (0xf0 & 0xcc) | 0xaa > (q, MASK, EX);
static constexpr uint32_t MUL = 0x3F803F80;
static constexpr uint32_t ADD = 0xC308C308;
frag_b[0] = __hfma2(*reinterpret_cast<nv_bfloat162*>(&lo),
*reinterpret_cast<const nv_bfloat162*>(&MUL),
*reinterpret_cast<const nv_bfloat162*>(&ADD));
frag_b[1] = __hfma2(*reinterpret_cast<nv_bfloat162*>(&hi),
*reinterpret_cast<const nv_bfloat162*>(&MUL),
*reinterpret_cast<const nv_bfloat162*>(&ADD));
return frag_b;
}
//
// Fast Int8ToFp16/Int8ToBf16: Efficiently dequantize 8bit int values to fp16 or
// bf16 Reference:
// - FP16:
// https://github.com/NVIDIA/FasterTransformer/blob/release/v5.3_tag/src/fastertransformer/cutlass_extensions/include/cutlass_extensions/interleaved_numeric_conversion.h#L53-L85
// - BF16:
// https://github.com/NVIDIA/FasterTransformer/blob/release/v5.3_tag/src/fastertransformer/cutlass_extensions/include/cutlass_extensions/interleaved_numeric_conversion.h#L125-L175
//
template <>
__device__ inline typename ScalarType<half>::FragB dequant<half, 8>(
int q, typename ScalarType<half>::FragB& frag_b) {
static constexpr uint32_t mask_for_elt_01 = 0x5250;
static constexpr uint32_t mask_for_elt_23 = 0x5351;
static constexpr uint32_t start_byte_for_fp16 = 0x64646464;
uint32_t lo = prmt<start_byte_for_fp16, mask_for_elt_01>(q);
uint32_t hi = prmt<start_byte_for_fp16, mask_for_elt_23>(q);
static constexpr uint32_t I8s_TO_F16s_MAGIC_NUM = 0x64806480;
frag_b[0] = __hsub2(*reinterpret_cast<half2*>(&lo),
*reinterpret_cast<const half2*>(&I8s_TO_F16s_MAGIC_NUM));
frag_b[1] = __hsub2(*reinterpret_cast<half2*>(&hi),
*reinterpret_cast<const half2*>(&I8s_TO_F16s_MAGIC_NUM));
return frag_b;
}
template <>
__device__ inline typename ScalarType<nv_bfloat16>::FragB
dequant<nv_bfloat16, 8>(int q,
typename ScalarType<nv_bfloat16>::FragB& frag_b) {
float fp32_intermediates[4];
uint32_t* fp32_intermediates_casted =
reinterpret_cast<uint32_t*>(fp32_intermediates);
static constexpr uint32_t fp32_base = 0x4B000000;
fp32_intermediates_casted[0] = __byte_perm(q, fp32_base, 0x7650);
fp32_intermediates_casted[1] = __byte_perm(q, fp32_base, 0x7652);
fp32_intermediates_casted[2] = __byte_perm(q, fp32_base, 0x7651);
fp32_intermediates_casted[3] = __byte_perm(q, fp32_base, 0x7653);
fp32_intermediates[0] -= 8388736.f;
fp32_intermediates[1] -= 8388736.f;
fp32_intermediates[2] -= 8388736.f;
fp32_intermediates[3] -= 8388736.f;
uint32_t* bf16_result_ptr = reinterpret_cast<uint32_t*>(&frag_b);
bf16_result_ptr[0] = __byte_perm(fp32_intermediates_casted[0],
fp32_intermediates_casted[1], 0x7632);
bf16_result_ptr[1] = __byte_perm(fp32_intermediates_casted[2],
fp32_intermediates_casted[3], 0x7632);
return frag_b;
}
// Multiply dequantized values by the corresponding quantization scale; used
// only for grouped quantization.
template <typename scalar_t>
__device__ inline void scale(typename ScalarType<scalar_t>::FragB& frag_b,
typename ScalarType<scalar_t>::FragS& frag_s,
int i) {
using scalar_t2 = typename ScalarType<scalar_t>::scalar_t2;
scalar_t2 s =
ScalarType<scalar_t>::num2num2(reinterpret_cast<scalar_t*>(&frag_s)[i]);
frag_b[0] = __hmul2(frag_b[0], s);
frag_b[1] = __hmul2(frag_b[1], s);
}
template <typename scalar_t>
__device__ inline void scale_and_sub(
typename ScalarType<scalar_t>::FragB& frag_b, scalar_t s, scalar_t zp) {
using scalar_t2 = typename ScalarType<scalar_t>::scalar_t2;
scalar_t2 s2 = ScalarType<scalar_t>::num2num2(s);
scalar_t2 zp2 = ScalarType<scalar_t>::num2num2(zp);
frag_b[0] = __hfma2(frag_b[0], s2, __hneg2(zp2));
frag_b[1] = __hfma2(frag_b[1], s2, __hneg2(zp2));
}
template <typename scalar_t>
__device__ inline void sub_zp(typename ScalarType<scalar_t>::FragB& frag_b,
typename ScalarType<scalar_t>::scalar_t2& frag_zp,
int i) {
using scalar_t2 = typename ScalarType<scalar_t>::scalar_t2;
scalar_t2 zp =
ScalarType<scalar_t>::num2num2(reinterpret_cast<scalar_t*>(&frag_zp)[i]);
frag_b[0] = __hsub2(frag_b[0], zp);
frag_b[1] = __hsub2(frag_b[1], zp);
}
// Same as above, but for act_order (each K is multiplied individually)
template <typename scalar_t>
__device__ inline void scale4(typename ScalarType<scalar_t>::FragB& frag_b,
typename ScalarType<scalar_t>::FragS& frag_s_1,
typename ScalarType<scalar_t>::FragS& frag_s_2,
typename ScalarType<scalar_t>::FragS& frag_s_3,
typename ScalarType<scalar_t>::FragS& frag_s_4,
int i) {
using scalar_t2 = typename ScalarType<scalar_t>::scalar_t2;
scalar_t2 s_val_1_2;
s_val_1_2.x = reinterpret_cast<scalar_t*>(&frag_s_1)[i];
s_val_1_2.y = reinterpret_cast<scalar_t*>(&frag_s_2)[i];
scalar_t2 s_val_3_4;
s_val_3_4.x = reinterpret_cast<scalar_t*>(&frag_s_3)[i];
s_val_3_4.y = reinterpret_cast<scalar_t*>(&frag_s_4)[i];
frag_b[0] = __hmul2(frag_b[0], s_val_1_2);
frag_b[1] = __hmul2(frag_b[1], s_val_3_4);
}
// Given 2 floats multiply by 2 scales (halves)
template <typename scalar_t>
__device__ inline void scale_float(float* c,
typename ScalarType<scalar_t>::FragS& s) {
scalar_t* s_ptr = reinterpret_cast<scalar_t*>(&s);
c[0] = __fmul_rn(c[0], ScalarType<scalar_t>::num2float(s_ptr[0]));
c[1] = __fmul_rn(c[1], ScalarType<scalar_t>::num2float(s_ptr[1]));
}
// Wait until barrier reaches `count`, then lock for current threadblock.
__device__ inline void barrier_acquire(int* lock, int count) {
if (threadIdx.x == 0) {
int state = -1;
do
// Guarantee that subsequent writes by this threadblock will be visible
// globally.
asm volatile("ld.global.acquire.gpu.b32 %0, [%1];\n"
: "=r"(state)
: "l"(lock));
while (state != count);
}
__syncthreads();
}
// Release barrier and increment visitation count.
__device__ inline void barrier_release(int* lock, bool reset = false) {
__syncthreads();
if (threadIdx.x == 0) {
if (reset) {
lock[0] = 0;
return;
}
int val = 1;
// Make sure that all writes since acquiring this barrier are visible
// globally, while releasing the barrier.
asm volatile("fence.acq_rel.gpu;\n");
asm volatile("red.relaxed.gpu.global.add.s32 [%0], %1;\n"
:
: "l"(lock), "r"(val));
}
}
// Wait until value of lock to be negative, and then add 1
__device__ inline void wait_negative_and_add(int* lock) {
if (threadIdx.x == 0) {
int state = 0;
do
// Guarantee that subsequent writes by this threadblock will be visible
// globally.
asm volatile("ld.global.acquire.gpu.b32 %0, [%1];\n"
: "=r"(state)
: "l"(lock));
while (state >= 0);
atomicAdd(lock, 1);
}
__syncthreads();
}
template <typename scalar_t, // compute dtype, half or nv_float16
const vllm::ScalarTypeId w_type_id, // weight ScalarType id
const int threads, // number of threads in a threadblock
const int thread_m_blocks, // number of 16x16 blocks in the m
// dimension (batchsize) of the
// threadblock
const int thread_n_blocks, // same for n dimension (output)
const int thread_k_blocks, // same for k dimension (reduction)
const bool m_block_size_8, // whether m_block_size == 8
// only works when thread_m_blocks == 1
const int stages, // number of stages for the async global->shared
// fetch pipeline
const bool has_act_order, // whether act_order is enabled
const bool has_zp, // whether zero-points are enabled
const int group_blocks, // number of consecutive 16x16 blocks
// with a separate quantization scale
const bool is_zp_float // is zero point of float16 type?
>
__global__ void Marlin(
const int4* __restrict__ A, // fp16 input matrix of shape mxk
const int4* __restrict__ B, // 4bit quantized weight matrix of shape kxn
int4* __restrict__ C, // fp16 output buffer of shape mxn
int4* __restrict__ C_tmp, // fp32 tmp output buffer (for reduce)
const int4* __restrict__ scales_ptr, // fp16 quantization scales of shape
// (k/groupsize)xn
const int4* __restrict__ zp_ptr, // 4bit packed zero-points of shape
// (k/groupsize)x(n/pack_factor)
const int* __restrict__ g_idx, // int32 group indices of shape k
const int32_t* __restrict__ sorted_token_ids_ptr, // moe sorted_ids
const int32_t* __restrict__ expert_ids_ptr, // moe expert ids
const int32_t* __restrict__ num_tokens_past_padded_ptr, // moe num tokens
const float* __restrict__ topk_weights_ptr, // moe top weights
int top_k, // num of experts per token
bool mul_topk_weights, // mul topk weights or not
bool is_ep, // expert parallelism
int num_groups, // number of scale groups per output channel
int prob_m, // batch dimension m
int prob_n, // output dimension n
int prob_k, // reduction dimension k
int* locks, // extra global storage for barrier synchronization
bool use_atomic_add, // whether to use atomic add to reduce
bool use_fp32_reduce // whether to use fp32 global reduce
) {
// Each threadblock processes one "stripe" of the B matrix with (roughly) the
// same size, which might involve multiple column "slices" (of width 16 *
// `thread_n_blocks`). Stripes are defined as shown in the 3x3 matrix 5 SM
// example:
// 0 1 3
// 0 2 3
// 1 2 4
// While this kind of partitioning makes things somewhat more complicated, it
// ensures good utilization of all SMs for many kinds of shape and GPU
// configurations, while requiring as few slow global cross-threadblock
// reductions as possible.
using Dtype = ScalarType<scalar_t>;
using scalar_t2 = typename ScalarType<scalar_t>::scalar_t2;
using FragA = typename ScalarType<scalar_t>::FragA;
using FragB = typename ScalarType<scalar_t>::FragB;
using FragC = typename ScalarType<scalar_t>::FragC;
using FragS = typename ScalarType<scalar_t>::FragS;
using FragZP = typename ScalarType<scalar_t>::FragZP;
extern __shared__ int4 sh[];
static constexpr auto w_type = vllm::ScalarType::from_id(w_type_id);
constexpr int pack_factor = 32 / w_type.size_bits();
static_assert(thread_m_blocks == 1 || !m_block_size_8);
constexpr int moe_block_size = m_block_size_8 ? 8 : (16 * thread_m_blocks);
const int group_size =
(!has_act_order && group_blocks == -1) ? prob_k : prob_k / num_groups;
const int scales_expert_stride = prob_n * prob_k / group_size / 8;
const int zp_expert_stride =
is_zp_float ? prob_n * prob_k / group_size / 8
: prob_n * prob_k / group_size / (pack_factor * 4);
// parallel: num valid moe blocks
int num_tokens_past_padded = num_tokens_past_padded_ptr[0];
int parallel = num_tokens_past_padded / moe_block_size;
int num_valid_blocks = parallel;
if (is_ep) {
for (int i = 0; i < parallel; i++) {
if (expert_ids_ptr[i] == -1) num_valid_blocks--;
}
}
int num_invalid_blocks = parallel - num_valid_blocks;
parallel = num_valid_blocks;
int k_tiles = prob_k / 16 / thread_k_blocks;
int n_tiles = prob_n / 16 / thread_n_blocks;
int iters = div_ceil(k_tiles * n_tiles * parallel, gridDim.x);
if constexpr (!has_act_order && group_blocks != -1) {
if (group_blocks >= thread_k_blocks) {
// Ensure that the number of tiles in each stripe is a multiple of the
// groupsize; this avoids an annoying special case where a stripe starts
// in the middle of group.
iters = (group_blocks / thread_k_blocks) *
div_ceil(iters, (group_blocks / thread_k_blocks));
}
}
int slice_row = (iters * blockIdx.x) % k_tiles;
int slice_col_par = (iters * blockIdx.x) / k_tiles;
int slice_col = slice_col_par;
int slice_iters; // number of threadblock tiles in the current slice
int slice_count =
0; // total number of active threadblocks in the current slice
int slice_idx; // index of threadblock in current slice; numbered bottom to
// top
int par_id = 0;
int block_id = -1;
int64_t expert_id = 0; // use int64 to avoid computation result overflow
int old_expert_id = 0;
int64_t B_expert_off = 0;
int4* sh_block_sorted_ids_int4 = sh;
int32_t* sh_block_sorted_ids =
reinterpret_cast<int*>(sh_block_sorted_ids_int4);
int4* sh_block_topk_weights_int4 =
sh_block_sorted_ids_int4 + moe_block_size / 4;
scalar_t2* sh_block_topk_weights =
reinterpret_cast<scalar_t2*>(sh_block_topk_weights_int4);
int4* sh_new = sh_block_topk_weights_int4 + moe_block_size / 4;
int32_t block_num_valid_tokens = 0;
int32_t locks_off = 0;
// We can easily implement parallel problem execution by just remapping
// indices and advancing global pointers
if (slice_col_par >= n_tiles) {
slice_col = slice_col_par % n_tiles;
par_id = slice_col_par / n_tiles;
}
if (parallel * n_tiles >= gridDim.x) {
// when parallel * n_tiles >= sms
// then there are at most $sms$ conflict tile blocks
locks_off = blockIdx.x;
} else {
locks_off = (iters * blockIdx.x) / k_tiles - 1;
}
// read moe block data given block_id
// block_sorted_ids / block_num_valid_tokens / block_topk_weights
auto read_moe_block_data = [&](int block_id) {
block_num_valid_tokens = moe_block_size;
#pragma unroll
for (int i = 0; i < moe_block_size / 4; i++) {
int4 sorted_token_ids_int4 = reinterpret_cast<const int4*>(
sorted_token_ids_ptr)[block_id * moe_block_size / 4 + i];
int* sorted_token_ids = reinterpret_cast<int*>(&sorted_token_ids_int4);
#pragma unroll
for (int j = 0; j < 4; j++) {
if (sorted_token_ids[j] >= prob_m * top_k) {
block_num_valid_tokens = i * 4 + j;
break;
}
}
if (block_num_valid_tokens != moe_block_size) break;
}
__syncthreads();
int tid4 = threadIdx.x / 4;
if (threadIdx.x % 4 == 0 && threadIdx.x < block_num_valid_tokens) {
sh_block_sorted_ids_int4[tid4] = reinterpret_cast<const int4*>(
sorted_token_ids_ptr)[block_id * moe_block_size / 4 + tid4];
if (mul_topk_weights) {
#pragma unroll
for (int i = 0; i < 4; i++) {
sh_block_topk_weights[tid4 * 4 + i] =
Dtype::num2num2(Dtype::float2num(
topk_weights_ptr[sh_block_sorted_ids[tid4 * 4 + i]]));
}
}
}
__syncthreads();
};
// when move to next moe block, find the next block_id and expert_id
// and then read moe block data
auto update_next_moe_block_data = [&]() {
if (par_id >= parallel) return;
old_expert_id = expert_id;
if (num_invalid_blocks > 0) {
int skip_count = block_id == -1 ? par_id : 0;
block_id++;
for (int i = block_id; i < num_tokens_past_padded / moe_block_size; i++) {
expert_id = expert_ids_ptr[i];
if (expert_id != -1) {
if (skip_count == 0) {
block_id = i;
break;
};
skip_count--;
};
}
} else {
block_id = par_id;
expert_id = expert_ids_ptr[block_id];
}
B_expert_off = expert_id * prob_n * prob_k / (pack_factor * 4);
scales_ptr += (expert_id - old_expert_id) * scales_expert_stride;
if constexpr (has_zp) {
zp_ptr += (expert_id - old_expert_id) * zp_expert_stride;
}
if constexpr (has_act_order) {
g_idx += (expert_id - old_expert_id) * prob_k;
}
read_moe_block_data(block_id);
};
// Compute all information about the current slice which is required for
// synchronization.
auto init_slice = [&](bool first_init = false) {
slice_iters =
iters * (blockIdx.x + 1) - (k_tiles * slice_col_par + slice_row);
if (slice_iters < 0 || slice_col_par >= n_tiles * parallel) slice_iters = 0;
if (slice_iters == 0) return;
if (slice_row + slice_iters > k_tiles) slice_iters = k_tiles - slice_row;
slice_count = 1;
slice_idx = 0;
int col_first = iters * div_ceil(k_tiles * slice_col_par, iters);
if (col_first <= k_tiles * (slice_col_par + 1)) {
int col_off = col_first - k_tiles * slice_col_par;
slice_count = div_ceil(k_tiles - col_off, iters);
if (col_off > 0) slice_count++;
int delta_first = iters * blockIdx.x - col_first;
if (delta_first < 0 || (col_off == 0 && delta_first == 0))
slice_idx = slice_count - 1;
else {
slice_idx = slice_count - 1 - delta_first / iters;
if (col_off > 0) slice_idx--;
}
}
if (parallel * n_tiles >= gridDim.x) {
if (slice_count > 1 && slice_idx == slice_count - 1) {
locks_off++;
}
} else {
locks_off++;
}
if (first_init && use_atomic_add && slice_count > 1 && slice_idx == 0) {
constexpr int threads_per_m = 16 * thread_n_blocks / 8;
int m_per_thread =
div_ceil(block_num_valid_tokens, threads / threads_per_m);
for (int i = 0; i < m_per_thread; i++) {
int row = threads / threads_per_m * i + threadIdx.x / threads_per_m;
if (row < block_num_valid_tokens) {
int64_t sorted_row = sh_block_sorted_ids[row];
int col = slice_col * 16 * thread_n_blocks / 8 +
threadIdx.x % threads_per_m;
C[sorted_row * prob_n / 8 + col] = {0, 0, 0, 0};
}
}
// After write zero to output, write a negative value to lock.
// Every SM that processes the same slice would wait for
// the negative value, and then atomicAdd 1 to it.
// After all SMs are processed, the lock value would back to 0 again.
__syncthreads();
if (threadIdx.x == 0) locks[locks_off] = 1 - slice_count;
}
if (slice_col == n_tiles) {
slice_col = 0;
par_id++;
update_next_moe_block_data();
}
};
update_next_moe_block_data();
init_slice(true);
// A sizes/strides
// stride of the A matrix in global memory
int a_gl_stride = prob_k / 8;
// stride of an A matrix tile in shared memory
constexpr int a_sh_stride = 16 * thread_k_blocks / 8;
// delta between subsequent A tiles in global memory
constexpr int a_gl_rd_delta_o = 16 * thread_k_blocks / 8;
// between subsequent accesses within a tile
int a_gl_rd_delta_i = a_gl_stride * (threads / a_gl_rd_delta_o);
// between shared memory writes
constexpr int a_sh_wr_delta = a_sh_stride * (threads / a_gl_rd_delta_o);
// between shared memory tile reads
constexpr int a_sh_rd_delta_o = 2 * ((threads / 32) / (thread_n_blocks / 4));
// within a shared memory tile
constexpr int a_sh_rd_delta_i = a_sh_stride * 16;
// overall size of a tile
constexpr int a_sh_stage = a_sh_stride * (16 * thread_m_blocks);
// number of shared write iterations for a tile
constexpr int a_sh_wr_iters = div_ceil(a_sh_stage, a_sh_wr_delta);
// B sizes/strides
int b_gl_stride = 16 * prob_n / (pack_factor * 4);
constexpr int b_sh_stride = ((thread_n_blocks * 16) * 16 / pack_factor) / 4;
constexpr int b_thread_vecs = w_type.size_bits() == 4 ? 1 : 2;
constexpr int b_sh_stride_threads = b_sh_stride / b_thread_vecs;
int b_gl_rd_delta_o = b_gl_stride * thread_k_blocks;
int b_gl_rd_delta_i = b_gl_stride * (threads / b_sh_stride_threads);
constexpr int b_sh_wr_delta = threads * b_thread_vecs;
constexpr int b_sh_rd_delta = threads * b_thread_vecs;
constexpr int b_sh_stage = b_sh_stride * thread_k_blocks;
constexpr int b_sh_wr_iters = b_sh_stage / b_sh_wr_delta;
// Scale sizes/strides without act_order
int s_gl_stride = prob_n / 8;
constexpr int s_sh_stride = 16 * thread_n_blocks / 8;
constexpr int s_tb_groups =
!has_act_order && group_blocks != -1 && group_blocks < thread_k_blocks
? thread_k_blocks / group_blocks
: 1;
constexpr int s_sh_stage = s_tb_groups * s_sh_stride;
int s_gl_rd_delta = s_gl_stride;
// Scale size/strides with act_order
constexpr int tb_k = 16 * thread_k_blocks;
constexpr int g_idx_stage = has_act_order ? (tb_k * sizeof(int)) / 16 : 0;
// constexpr int act_s_row_stride = 1;
// int act_s_col_stride = act_s_row_stride * num_groups;
int act_s_col_stride = 1;
int act_s_col_warp_stride = act_s_col_stride * 8;
int tb_n_warps = thread_n_blocks / 4;
int act_s_col_tb_stride = act_s_col_warp_stride * tb_n_warps;
// Zero-points sizes/strides
int zp_gl_stride = is_zp_float ? prob_n / 8 : (prob_n / pack_factor) / 4;
constexpr int zp_sh_stride = is_zp_float
? 16 * thread_n_blocks / 8
: ((16 * thread_n_blocks) / pack_factor) / 4;
constexpr int zp_tb_groups = s_tb_groups;
constexpr int zp_sh_stage = has_zp ? zp_tb_groups * zp_sh_stride : 0;
int zp_gl_rd_delta = zp_gl_stride;
// Global A read index of current thread.
int a_gl_rd = a_gl_stride * (threadIdx.x / a_gl_rd_delta_o) +
(threadIdx.x % a_gl_rd_delta_o);
a_gl_rd += a_gl_rd_delta_o * slice_row;
// Shared write index of current thread.
int a_sh_wr = a_sh_stride * (threadIdx.x / a_gl_rd_delta_o) +
(threadIdx.x % a_gl_rd_delta_o);
// Shared read index.
int a_sh_rd =
a_sh_stride * ((threadIdx.x % 32) % (16 / (m_block_size_8 ? 2 : 1))) +
(threadIdx.x % 32) / (16 / (m_block_size_8 ? 2 : 1));
a_sh_rd += 2 * ((threadIdx.x / 32) / (thread_n_blocks / 4));
int b_gl_rd = b_gl_stride * (threadIdx.x / b_sh_stride_threads) +
(threadIdx.x % b_sh_stride_threads) * b_thread_vecs;
b_gl_rd += b_sh_stride * slice_col;
b_gl_rd += b_gl_rd_delta_o * slice_row;
int b_sh_wr = threadIdx.x * b_thread_vecs;
int b_sh_rd = threadIdx.x * b_thread_vecs;
// For act_order
constexpr int k_iter_size = tb_k / b_sh_wr_iters;
int slice_k_start = tb_k * slice_row;
int slice_k_finish = slice_k_start + tb_k * slice_iters;
int slice_k_start_shared_fetch = slice_k_start;
int slice_n_offset = act_s_col_tb_stride * slice_col;
// No act_order
int s_gl_rd;
if constexpr (!has_act_order) {
if constexpr (group_blocks == -1) {
s_gl_rd = s_sh_stride * slice_col + threadIdx.x;
} else {
s_gl_rd = s_gl_stride * ((thread_k_blocks * slice_row) / group_blocks) +
s_sh_stride * slice_col + threadIdx.x;
}
}
int s_sh_wr = threadIdx.x;
bool s_sh_wr_pred = threadIdx.x < s_sh_stride;
// Zero-points
int zp_gl_rd;
if constexpr (has_zp) {
if constexpr (group_blocks == -1) {
zp_gl_rd = zp_sh_stride * slice_col + threadIdx.x;
} else {
zp_gl_rd = zp_gl_stride * ((thread_k_blocks * slice_row) / group_blocks) +
zp_sh_stride * slice_col + threadIdx.x;
}
}
int zp_sh_wr = threadIdx.x;
bool zp_sh_wr_pred = threadIdx.x < zp_sh_stride;
// We use a different scale layout for grouped and column-wise quantization as
// we scale a `half2` tile in column-major layout in the former and in
// row-major in the latter case.
int s_sh_rd;
if constexpr (group_blocks != -1)
s_sh_rd = 8 * ((threadIdx.x / 32) % (thread_n_blocks / 4)) +
(threadIdx.x % 32) / 4;
else if constexpr (group_blocks == -1 && (m_block_size_8 || has_zp))
s_sh_rd = 8 * ((threadIdx.x / 32) % (thread_n_blocks / 4)) +
(threadIdx.x % 32) / 8;
else
s_sh_rd = 8 * ((threadIdx.x / 32) % (thread_n_blocks / 4)) +
(threadIdx.x % 32) % 4;
// Zero-points have the same read layout as the scales
// (without column-wise case)
constexpr int num_col_threads = 8;
constexpr int num_row_threads = 4;
constexpr int num_ints_per_thread = 8 / pack_factor;
int zp_sh_rd;
if constexpr (has_zp) {
if constexpr (is_zp_float) {
if constexpr (group_blocks != -1) {
zp_sh_rd = 8 * ((threadIdx.x / 32) % (thread_n_blocks / 4)) +
(threadIdx.x % 32) / 4;
}
} else {
zp_sh_rd = num_ints_per_thread * num_col_threads *
((threadIdx.x / 32) % (thread_n_blocks / 4)) +
num_ints_per_thread * ((threadIdx.x % 32) / num_row_threads);
}
}
// To ensure that writing and reading A tiles to/from shared memory, the
// latter in fragment format, is fully bank conflict free, we need to use a
// rather fancy XOR-based layout. The key here is that neither reads nor
// writes of the 16-byte `int4` blocks of 8 consecutive threads involve the
// same shared memory banks. Further, it seems (based on NSight-Compute) that
// each warp must also write a consecutive memory segment?
auto transform_a = [&](int i) {
int row = i / a_gl_rd_delta_o;
return a_gl_rd_delta_o * row + (i % a_gl_rd_delta_o) ^ row;
};
// Since the computation of this remapping is non-trivial and, due to our main
// loop unrolls, all shared memory accesses are static, we simply precompute
// both transformed reads and writes.
int a_sh_wr_trans[a_sh_wr_iters];
#pragma unroll
for (int i = 0; i < a_sh_wr_iters; i++)
a_sh_wr_trans[i] = transform_a(a_sh_wr_delta * i + a_sh_wr);
int a_sh_rd_trans[b_sh_wr_iters][thread_m_blocks];
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++) {
#pragma unroll
for (int j = 0; j < thread_m_blocks; j++)
a_sh_rd_trans[i][j] =
transform_a(a_sh_rd_delta_o * i + a_sh_rd_delta_i * j + a_sh_rd);
}
// Since B-accesses have non-constant stride they have to be computed at
// runtime; we break dependencies between subsequent accesses with a tile by
// maintining multiple pointers (we have enough registers), a tiny
// optimization.
const int4* B_ptr[b_sh_wr_iters];
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++)
B_ptr[i] = B + b_gl_rd_delta_i * i + b_gl_rd;
// Shared memory storage for global fetch pipelines.
int4* sh_a = sh_new;
int4* sh_b = sh_a + (stages * a_sh_stage);
int4* sh_g_idx = sh_b + (stages * b_sh_stage);
int4* sh_zp = sh_g_idx + (stages * g_idx_stage);
int4* sh_s = sh_zp + (stages * zp_sh_stage);
int4* sh_red = sh_b;
// Register storage for double buffer of shared memory reads.
FragA frag_a[2][thread_m_blocks];
I4 frag_b_quant[2][b_thread_vecs];
FragC frag_c[thread_m_blocks][4][2];
FragS frag_s[2][4]; // No act-order
FragS act_frag_s[2][4][4]; // For act-order
int frag_qzp[2][num_ints_per_thread]; // Zero-points
FragZP frag_zp; // Zero-points in fp16
FragZP frag_zpf[2]; // Zero-points in fp16 in HQQ
// Zero accumulators.
auto zero_accums = [&]() {
#pragma unroll
for (int i = 0; i < thread_m_blocks * 4 * 2 * 4; i++)
reinterpret_cast<float*>(frag_c)[i] = 0;
};
int sh_first_group_id = -1;
int sh_num_groups = -1;
constexpr int sh_max_num_groups = 32;
auto fetch_act_order_scales_to_shared = [&](bool is_async, int first_group_id,
int last_group_id) {
sh_first_group_id = first_group_id;
sh_num_groups = last_group_id - first_group_id + 1;
if (sh_num_groups < sh_max_num_groups) {
sh_num_groups = sh_max_num_groups;
}
if (sh_first_group_id + sh_num_groups > num_groups) {
sh_num_groups = num_groups - sh_first_group_id;
}
int row_offset = first_group_id * s_gl_stride;
if (is_async) {
for (int i = 0; i < sh_num_groups; i++) {
if (threadIdx.x < s_sh_stride) {
cp_async4_pred(&sh_s[(i * s_sh_stride) + threadIdx.x],
&scales_ptr[row_offset + (i * s_gl_stride) +
slice_n_offset + threadIdx.x]);
}
}
} else {
for (int i = 0; i < sh_num_groups; i++) {
if (threadIdx.x < s_sh_stride) {
sh_s[(i * s_sh_stride) + threadIdx.x] =
scales_ptr[row_offset + (i * s_gl_stride) + slice_n_offset +
threadIdx.x];
}
}
}
};
// Asynchronously fetch the next A, B and s tile from global to the next
// shared memory pipeline location.
int a_remaining_load_count_in_slice = stages;
auto fetch_to_shared = [&](int pipe, int a_off, bool pred = true) {
if (pred) {
int4* sh_a_stage = sh_a + a_sh_stage * pipe;
if (prob_k > thread_k_blocks * 16 * stages || slice_col == 0 ||
a_remaining_load_count_in_slice > 0) {
a_remaining_load_count_in_slice--;
#pragma unroll
for (int i = 0; i < a_sh_wr_iters; i++) {
int a_idx = a_gl_rd_delta_i * i + a_gl_rd + a_gl_rd_delta_o * a_off;
int row = a_idx / a_gl_stride;
int64_t sorted_row = 0;
if (!m_block_size_8 || row < 8)
sorted_row = sh_block_sorted_ids[row] / top_k;
int64_t true_idx = sorted_row * a_gl_stride + a_idx % a_gl_stride;
cp_async4_pred(&sh_a_stage[a_sh_wr_trans[i]], &A[true_idx],
row < block_num_valid_tokens);
}
}
int4* sh_b_stage = sh_b + b_sh_stage * pipe;
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++) {
#pragma unroll
for (int j = 0; j < b_thread_vecs; j++) {
cp_async4(&sh_b_stage[b_sh_wr_delta * i + b_sh_wr + j],
B_ptr[i] + j + B_expert_off);
}
B_ptr[i] += b_gl_rd_delta_o;
}
if constexpr (has_act_order) {
// Fetch g_idx thread-block portion
int full_pipe = a_off;
int cur_k = slice_k_start_shared_fetch + tb_k * full_pipe;
if (cur_k < prob_k && cur_k < slice_k_finish) {
int4* sh_g_idx_stage = sh_g_idx + g_idx_stage * pipe;
int4 const* cur_g_idx_stage_ptr =
reinterpret_cast<int4 const*>(&g_idx[cur_k]);
if (threadIdx.x < g_idx_stage) {
cp_async4_pred(&sh_g_idx_stage[threadIdx.x],
&cur_g_idx_stage_ptr[threadIdx.x]);
}
}
} else {
if constexpr (group_blocks != -1) {
int4* sh_s_stage = sh_s + s_sh_stage * pipe;
if constexpr (group_blocks >= thread_k_blocks) {
// Only fetch scales if this tile starts a new group
if (pipe % (group_blocks / thread_k_blocks) == 0) {
if (s_sh_wr_pred) {
cp_async4(&sh_s_stage[s_sh_wr], &scales_ptr[s_gl_rd]);
}
s_gl_rd += s_gl_rd_delta;
}
} else {
for (int i = 0; i < s_tb_groups; i++) {
if (s_sh_wr_pred) {
cp_async4(&sh_s_stage[i * s_sh_stride + s_sh_wr],
&scales_ptr[s_gl_rd]);
}
s_gl_rd += s_gl_rd_delta;
}
}
}
if constexpr (has_zp && group_blocks != -1) {
int4* sh_zp_stage = sh_zp + zp_sh_stage * pipe;
if constexpr (group_blocks >= thread_k_blocks) {
// Only fetch zero-points if this tile starts a new group
if (pipe % (group_blocks / thread_k_blocks) == 0) {
if (zp_sh_wr_pred) {
cp_async4(&sh_zp_stage[zp_sh_wr], &zp_ptr[zp_gl_rd]);
}
zp_gl_rd += zp_gl_rd_delta;
}
} else {
for (int i = 0; i < zp_tb_groups; i++) {
if (zp_sh_wr_pred) {
cp_async4(&sh_zp_stage[i * zp_sh_stride + zp_sh_wr],
&zp_ptr[zp_gl_rd]);
}
zp_gl_rd += zp_gl_rd_delta;
}
}
}
}
}
// Insert a fence even when we are winding down the pipeline to ensure that
// waiting is also correct at this point.
cp_async_fence();
};
auto fetch_col_zp_to_shared = [&]() {
if (zp_sh_wr_pred) {
cp_async4(&sh_zp[zp_sh_wr], &zp_ptr[zp_gl_rd]);
}
};
auto fetch_col_scale_to_shared = [&]() {
if (s_sh_wr_pred) {
cp_async4(&sh_s[s_sh_wr], &scales_ptr[s_gl_rd]);
}
};
// Wait until the next thread tile has been loaded to shared memory.
auto wait_for_stage = [&]() {
// We only have `stages - 2` active fetches since we are double buffering
// and can only issue the next fetch when it is guaranteed that the previous
// shared memory load is fully complete (as it may otherwise be
// overwritten).
cp_async_wait<stages - 2>();
__syncthreads();
};
// Load the next sub-tile from the current location in the shared memory pipe
// into the current register buffer.
auto fetch_to_registers = [&](int k, int pipe) {
int4* sh_a_stage = sh_a + a_sh_stage * pipe;
#pragma unroll
for (int i = 0; i < thread_m_blocks; i++)
ldsm<m_block_size_8 ? 2 : 4, scalar_t>(
frag_a[k % 2][i], &sh_a_stage[a_sh_rd_trans[k % b_sh_wr_iters][i]]);
int4* sh_b_stage = sh_b + b_sh_stage * pipe;
#pragma unroll
for (int i = 0; i < b_thread_vecs; i++) {
frag_b_quant[k % 2][i] = *reinterpret_cast<I4*>(
&sh_b_stage[b_sh_rd_delta * (k % b_sh_wr_iters) + b_sh_rd + i]);
}
};
bool is_same_group[stages];
int same_group_id[stages];
auto init_same_group = [&](int pipe) {
if constexpr (!has_act_order) {
return;
}
int4* sh_g_idx_stage = sh_g_idx + g_idx_stage * pipe;
int* sh_g_idx_int_ptr = reinterpret_cast<int*>(sh_g_idx_stage);
int group_id_1 = sh_g_idx_int_ptr[0];
int group_id_2 = sh_g_idx_int_ptr[tb_k - 1];
is_same_group[pipe] = group_id_1 == group_id_2;
same_group_id[pipe] = group_id_1;
};
auto fetch_scales_to_registers = [&](int k, int full_pipe) {
int pipe = full_pipe % stages;
if constexpr (!has_act_order) {
// No act-order case
if constexpr (group_blocks == -1) {
// load only when starting a new slice
if (k == 0 && full_pipe == 0) {
reinterpret_cast<int4*>(&frag_s)[0] = sh_s[s_sh_rd];
reinterpret_cast<int4*>(&frag_s)[1] = sh_s[s_sh_rd + 4];
}
} else if constexpr (group_blocks != -1) {
if constexpr (group_blocks >= thread_k_blocks) {
int4* sh_s_stage =
sh_s + s_sh_stage * ((group_blocks / thread_k_blocks) *
(pipe / (group_blocks / thread_k_blocks)));
reinterpret_cast<int4*>(&frag_s[k % 2])[0] = sh_s_stage[s_sh_rd];
} else {
int warp_id = threadIdx.x / 32;
int n_warps = thread_n_blocks / 4;
int warp_row = warp_id / n_warps;
int cur_k = warp_row * 16;
cur_k += k_iter_size * (k % b_sh_wr_iters);
int k_blocks = cur_k / 16;
int cur_group_id = k_blocks / group_blocks;
int4* sh_s_stage = sh_s + s_sh_stage * pipe;
reinterpret_cast<int4*>(&frag_s[k % 2])[0] =
sh_s_stage[s_sh_rd + cur_group_id * s_sh_stride];
}
}
return;
}
// Act-order case
// Determine K of the "current" thread-block
int cur_k = slice_k_start + tb_k * full_pipe;
if (cur_k >= prob_k || cur_k >= slice_k_finish) {
return;
}
// Reset (to current thread-block) since we read g_idx portion from the
// shared memory
cur_k = 0;
// Progress to current iteration
cur_k += k_iter_size * (k % b_sh_wr_iters);
// Determine "position" inside the thread-block (based on warp and
// thread-id)
int warp_id = threadIdx.x / 32;
int n_warps =
thread_n_blocks / 4; // Each warp processes 4 16-size tiles over N
int warp_row = warp_id / n_warps;
int warp_col = warp_id % n_warps;
cur_k += warp_row * 16;
int th_id = threadIdx.x % 32;
cur_k += (th_id % 4) * 2; // Due to tensor-core layout for fp16 B matrix
int s_col_shift =
/*slice_n_offset +*/ (act_s_col_warp_stride * warp_col) +
(th_id / 4) * act_s_col_stride;
if (is_same_group[pipe]) {
if (k % 2 == 0) {
*(reinterpret_cast<int4*>(&(act_frag_s[k % 2][0][0]))) =
sh_s[(same_group_id[pipe] - sh_first_group_id) * s_sh_stride +
s_col_shift];
} else {
*(reinterpret_cast<int4*>(&(act_frag_s[k % 2][0][0]))) =
*(reinterpret_cast<int4*>(&(act_frag_s[(k - 1) % 2][0][0])));
}
for (int i = 1; i < 4; i++) {
*(reinterpret_cast<int4*>(&(act_frag_s[k % 2][i][0]))) =
*(reinterpret_cast<int4*>(&(act_frag_s[k % 2][0][0])));
}
return;
}
int4* sh_g_idx_stage = sh_g_idx + g_idx_stage * pipe;
int* sh_g_idx_int_ptr = reinterpret_cast<int*>(sh_g_idx_stage);
constexpr int k_frag_offsets[4] = {0, 1, 8,
9}; // Tensor core offsets per thread
#pragma unroll
for (int i = 0; i < 4; i++) {
int actual_k = cur_k + k_frag_offsets[i];
int group_id = sh_g_idx_int_ptr[actual_k];
int rel_group_id = group_id - sh_first_group_id;
*(reinterpret_cast<int4*>(&(act_frag_s[k % 2][i][0]))) =
sh_s[rel_group_id * s_sh_stride + s_col_shift];
}
};
auto fetch_zp_to_registers = [&](int k, int full_pipe) {
// This code does not handle group_blocks == 0,
// which signifies act_order.
// has_zp implies AWQ, which doesn't have act_order,
static_assert(!has_zp || group_blocks != 0);
if constexpr (has_zp && !is_zp_float) {
int pipe = full_pipe % stages;
if constexpr (group_blocks == -1) {
// load only when starting a new slice
if (k == 0 && full_pipe == 0) {
#pragma unroll
for (int i = 0; i < num_ints_per_thread; i++) {
frag_qzp[k % 2][i] = (reinterpret_cast<int*>(sh_zp))[zp_sh_rd + i];
}
}
} else if constexpr (group_blocks >= thread_k_blocks) {
int4* sh_zp_stage =
sh_zp + zp_sh_stage * ((group_blocks / thread_k_blocks) *
(pipe / (group_blocks / thread_k_blocks)));
for (int i = 0; i < num_ints_per_thread; i++) {
frag_qzp[k % 2][i] =
(reinterpret_cast<int*>(sh_zp_stage))[zp_sh_rd + i];
}
} else {
int warp_id = threadIdx.x / 32;
int n_warps = thread_n_blocks / 4;
int warp_row = warp_id / n_warps;
int cur_k = warp_row * 16;
cur_k += k_iter_size * (k % b_sh_wr_iters);
int k_blocks = cur_k / 16;
int cur_group_id = 0;
// Suppress bogus and persistent divide-by-zero warning
#pragma nv_diagnostic push
#pragma nv_diag_suppress divide_by_zero
cur_group_id = k_blocks / group_blocks;
#pragma nv_diagnostic pop
int4* sh_zp_stage = sh_zp + zp_sh_stage * pipe;
sh_zp_stage += cur_group_id * zp_sh_stride;
for (int i = 0; i < num_ints_per_thread; i++) {
frag_qzp[k % 2][i] =
(reinterpret_cast<int*>(sh_zp_stage))[zp_sh_rd + i];
}
}
}
else if constexpr (has_zp && is_zp_float) {
int pipe = full_pipe % stages;
if constexpr (group_blocks != -1) {
if constexpr (group_blocks >= thread_k_blocks) {
int4* sh_zp_stage =
sh_zp + zp_sh_stage * ((group_blocks / thread_k_blocks) *
(pipe / (group_blocks / thread_k_blocks)));
reinterpret_cast<int4*>(&frag_zpf[k % 2])[0] = sh_zp_stage[zp_sh_rd];
} else {
int warp_id = threadIdx.x / 32;
int n_warps = thread_n_blocks / 4;
int warp_row = warp_id / n_warps;
int cur_k = warp_row * 16;
cur_k += k_iter_size * (k % b_sh_wr_iters);
int k_blocks = cur_k / 16;
// Suppress bogus and persistent divide-by-zero warning
#pragma nv_diagnostic push
#pragma nv_diag_suppress divide_by_zero
int cur_group_id = k_blocks / group_blocks;
#pragma nv_diagnostic pop
int4* sh_zp_stage = sh_zp + zp_sh_stage * pipe;
reinterpret_cast<int4*>(&frag_zpf[k % 2])[0] =
sh_zp_stage[zp_sh_rd + cur_group_id * zp_sh_stride];
}
}
}
};
// Execute the actual tensor core matmul of a sub-tile.
bool is_first_matmul_in_slice = true;
auto matmul = [&](int k) {
int k2 = k % 2;
const bool is_new_zp =
((group_blocks != -1) && (group_blocks < thread_k_blocks || k == 0)) ||
(group_blocks == -1 && is_first_matmul_in_slice);
if constexpr (has_zp && !is_zp_float) {
if (is_new_zp) {
if constexpr (group_blocks == -1) is_first_matmul_in_slice = false;
FragB frag_zp_0;
FragB frag_zp_1;
int zp_quant_0, zp_quant_1;
if constexpr (w_type.size_bits() == 4) {
zp_quant_0 = frag_qzp[k2][0];
zp_quant_1 = zp_quant_0 >> 8;
} else {
static_assert(w_type.size_bits() == 8);
zp_quant_0 = frag_qzp[k2][0];
zp_quant_1 = frag_qzp[k2][1];
}
dequant<scalar_t, w_type.size_bits()>(zp_quant_0, frag_zp_0);
dequant<scalar_t, w_type.size_bits()>(zp_quant_1, frag_zp_1);
frag_zp[0] = frag_zp_0[0];
frag_zp[1] = frag_zp_0[1];
frag_zp[2] = frag_zp_1[0];
frag_zp[3] = frag_zp_1[1];
}
}
// We have the m dimension as the inner loop in order to encourage overlapping
// dequantization and matmul operations.
#pragma unroll
for (int j = 0; j < 4; j++) {
FragB frag_b0;
FragB frag_b1;
int b_quant_0, b_quant_1;
if constexpr (w_type.size_bits() == 4) {
b_quant_0 = frag_b_quant[k2][0][j];
b_quant_1 = b_quant_0 >> 8;
} else {
static_assert(w_type.size_bits() == 8);
int* frag_b_quant_ptr = reinterpret_cast<int*>(frag_b_quant[k2]);
b_quant_0 = frag_b_quant_ptr[j * 2 + 0];
b_quant_1 = frag_b_quant_ptr[j * 2 + 1];
}
dequant<scalar_t, w_type.size_bits()>(b_quant_0, frag_b0);
dequant<scalar_t, w_type.size_bits()>(b_quant_1, frag_b1);
// Apply scale to frag_b0
if constexpr (has_act_order) {
static_assert(group_blocks != -1);
scale4<scalar_t>(frag_b0, act_frag_s[k2][0][j], act_frag_s[k2][1][j],
act_frag_s[k2][2][j], act_frag_s[k2][3][j], 0);
scale4<scalar_t>(frag_b1, act_frag_s[k2][0][j], act_frag_s[k2][1][j],
act_frag_s[k][2][j], act_frag_s[k2][3][j], 1);
} else if constexpr (has_zp && !is_zp_float && group_blocks == -1) {
int idx = (threadIdx.x / 4) % 2;
scalar_t2 s2 = Dtype::nums2num2(
reinterpret_cast<scalar_t*>(&frag_s[j / 2][j % 2 * 2 + 0])[idx],
reinterpret_cast<scalar_t*>(&frag_s[j / 2][j % 2 * 2 + 1])[idx]);
if (is_new_zp) frag_zp[j] = __hmul2(frag_zp[j], s2);
scale_and_sub<scalar_t>(frag_b0, s2.x, frag_zp[j].x);
scale_and_sub<scalar_t>(frag_b1, s2.y, frag_zp[j].y);
} else if constexpr (has_zp && !is_zp_float && group_blocks != -1) {
if (is_new_zp)
frag_zp[j] = __hmul2(frag_zp[j],
*reinterpret_cast<scalar_t2*>(&frag_s[k2][j]));
scale_and_sub<scalar_t>(frag_b0, frag_s[k % 2][j][0].x, frag_zp[j].x);
scale_and_sub<scalar_t>(frag_b1, frag_s[k % 2][j][0].y, frag_zp[j].y);
} else if constexpr (has_zp && is_zp_float && group_blocks != -1) {
if (is_new_zp)
frag_zpf[k2][j] = __hmul2(
frag_zpf[k2][j], *reinterpret_cast<scalar_t2*>(&frag_s[k2][j]));
scale_and_sub<scalar_t>(frag_b0, frag_s[k2][j].x, frag_zpf[k2][j].x);
scale_and_sub<scalar_t>(frag_b1, frag_s[k2][j].y, frag_zpf[k2][j].y);
} else if constexpr (group_blocks != -1) {
scale<scalar_t>(frag_b0, frag_s[k2][j], 0);
scale<scalar_t>(frag_b1, frag_s[k2][j], 1);
}
#pragma unroll
for (int i = 0; i < thread_m_blocks; i++) {
if constexpr (m_block_size_8) {
mma_trans<scalar_t>(frag_a[k2][i], frag_b0, frag_b1, frag_c[i][j][0]);
} else {
mma<scalar_t>(frag_a[k2][i], frag_b0, frag_c[i][j][0]);
mma<scalar_t>(frag_a[k2][i], frag_b1, frag_c[i][j][1]);
}
}
}
};
// Since we slice across the k dimension of a tile in order to increase the
// number of warps while keeping the n dimension of a tile reasonable, we have
// multiple warps that accumulate their partial sums of the same output
// location; which we have to reduce over in the end. We do in shared memory.
auto thread_block_reduce = [&]() {
constexpr int red_off = threads / b_sh_stride_threads / 2;
if (red_off >= 1) {
int red_idx = threadIdx.x / b_sh_stride_threads;
constexpr int red_sh_stride = b_sh_stride_threads * 4 * 2;
constexpr int red_sh_delta = b_sh_stride_threads;
int red_sh_rd = red_sh_stride * (threadIdx.x / b_sh_stride_threads) +
(threadIdx.x % b_sh_stride_threads);
// Parallel logarithmic shared memory reduction. We make sure to avoid any
// unnecessary read or write iterations, e.g., for two warps we write only
// once by warp 1 and read only once by warp 0.
#pragma unroll
for (int m_block = 0; m_block < thread_m_blocks; m_block++) {
#pragma unroll
for (int i = red_off; i > 0; i /= 2) {
if (i <= red_idx && red_idx < 2 * i) {
#pragma unroll
for (int j = 0; j < 4 * 2; j += (m_block_size_8 ? 2 : 1)) {
int red_sh_wr =
red_sh_delta * j + (red_sh_rd - red_sh_stride * i);
if (i < red_off) {
float* c_rd = reinterpret_cast<float*>(
&sh_red[red_sh_delta * j + red_sh_rd]);
float* c_wr = reinterpret_cast<float*>(&sh_red[red_sh_wr]);
#pragma unroll
for (int k = 0; k < 4; k++)
reinterpret_cast<FragC*>(frag_c)[4 * 2 * m_block + j][k] +=
c_rd[k] + c_wr[k];
}
sh_red[red_sh_wr] =
reinterpret_cast<int4*>(&frag_c)[4 * 2 * m_block + j];
}
}
__syncthreads();
}
if (red_idx == 0) {
#pragma unroll
for (int i = 0; i < 4 * 2; i += (m_block_size_8 ? 2 : 1)) {
float* c_rd =
reinterpret_cast<float*>(&sh_red[red_sh_delta * i + red_sh_rd]);
#pragma unroll
for (int j = 0; j < 4; j++)
reinterpret_cast<FragC*>(frag_c)[4 * 2 * m_block + i][j] +=
c_rd[j];
}
}
__syncthreads();
}
}
};
// Since multiple threadblocks may process parts of the same column slice, we
// finally have to globally reduce over the results. As the striped
// partitioning minimizes the number of such reductions and our outputs are
// usually rather small, we perform this reduction serially in L2 cache.
auto global_reduce_fp16 = [&](bool first = false, bool last = false) {
// We are very careful here to reduce directly in the output buffer to
// maximize L2 cache utilization in this step. To do this, we write out
// results in FP16 (but still reduce with FP32 compute).
constexpr int active_threads = 32 * thread_n_blocks / 4;
bool is_th_active = threadIdx.x < active_threads;
if (!is_th_active) {
return;
}
int c_gl_stride = prob_n / 8;
int c_gl_wr_delta_o = 8 * c_gl_stride;
int c_gl_wr_delta_i = 4 * (active_threads / 32);
int c_gl_wr;
if constexpr (m_block_size_8) {
c_gl_wr = c_gl_stride * ((threadIdx.x % 4) * 2) + 4 * (threadIdx.x / 32) +
(threadIdx.x % 32) / 8;
c_gl_wr += (2 * thread_n_blocks) * slice_col;
} else {
c_gl_wr = c_gl_stride * ((threadIdx.x % 32) / 4) +
4 * (threadIdx.x / 32) + threadIdx.x % 4;
c_gl_wr += (2 * thread_n_blocks) * slice_col;
}
constexpr int c_sh_wr_delta = active_threads;
int c_sh_wr = threadIdx.x;
if (!first) {
#pragma unroll
for (int i = 0; i < (m_block_size_8 ? 2 : thread_m_blocks * 4); i++) {
int c_idx;
if constexpr (m_block_size_8)
c_idx = c_gl_wr + i * c_gl_stride +
(threadIdx.x % 8) / 4 * c_gl_wr_delta_i;
else
c_idx =
c_gl_wr + c_gl_wr_delta_o * (i / 2) + c_gl_wr_delta_i * (i % 2);
if (c_idx / c_gl_stride < block_num_valid_tokens) {
int64_t sorted_row = sh_block_sorted_ids[c_idx / c_gl_stride];
int64_t true_idx = sorted_row * c_gl_stride + c_idx % c_gl_stride;
sh_red[c_sh_wr + c_sh_wr_delta * i] = C[true_idx];
}
}
}
#pragma unroll
for (int i = 0; i < (m_block_size_8 ? 2 : thread_m_blocks * 4); i++) {
if (!first) {
int4 c_red = sh_red[c_sh_wr + i * c_sh_wr_delta];
#pragma unroll
for (int j = 0; j < 2 * 4; j++) {
int delta = 0;
if constexpr (m_block_size_8) {
delta = j % 2 == 1 ? -2 : 0;
}
reinterpret_cast<float*>(
&frag_c)[4 * 2 * 4 * (i / 4) + 4 * j + (i % 4) + delta] +=
Dtype::num2float(reinterpret_cast<scalar_t*>(&c_red)[j]);
}
}
if (!last) {
int4 c;
#pragma unroll
for (int j = 0; j < 2 * 4; j++) {
int delta = 0;
if constexpr (m_block_size_8) {
delta = j % 2 == 1 ? -2 : 0;
}
reinterpret_cast<scalar_t*>(&c)[j] =
Dtype::float2num(reinterpret_cast<float*>(
&frag_c)[4 * 2 * 4 * (i / 4) + 4 * j + (i % 4) + delta]);
}
int c_idx;
if constexpr (m_block_size_8)
c_idx = c_gl_wr + i * c_gl_stride +
(threadIdx.x % 8) / 4 * c_gl_wr_delta_i;
else
c_idx =
c_gl_wr + c_gl_wr_delta_o * (i / 2) + c_gl_wr_delta_i * (i % 2);
if (c_idx / c_gl_stride < block_num_valid_tokens) {
int64_t sorted_row = sh_block_sorted_ids[c_idx / c_gl_stride];
int64_t true_idx = sorted_row * c_gl_stride + c_idx % c_gl_stride;
C[true_idx] = c;
}
}
}
};
// Globally reduce over threadblocks that compute the same column block.
// We use a tmp C buffer to reduce in full fp32 precision.
auto global_reduce_fp32 = [&](bool first = false, bool last = false) {
constexpr int tb_m = thread_m_blocks * 16;
constexpr int tb_n = thread_n_blocks * 16;
constexpr int c_size = tb_m * tb_n * sizeof(float) / 16;
constexpr int active_threads = 32 * thread_n_blocks / 4;
bool is_th_active = threadIdx.x < active_threads;
constexpr int num_floats = thread_m_blocks * 4 * 2 * 4;
constexpr int th_size = num_floats * sizeof(float) / 16;
int c_cur_offset = locks_off * c_size;
if (!is_th_active) {
return;
}
if (!first) {
float* frag_c_ptr = reinterpret_cast<float*>(&frag_c);
#pragma unroll
for (int k = 0; k < th_size; k++) {
if constexpr (m_block_size_8) {
if (k % 2) continue;
} else {
if (k / 8 * 16 + (threadIdx.x % 32) / 4 >= block_num_valid_tokens)
continue;
}
sh_red[threadIdx.x] =
C_tmp[c_cur_offset + active_threads * k + threadIdx.x];
float* sh_c_ptr = reinterpret_cast<float*>(&sh_red[threadIdx.x]);
#pragma unroll
for (int f = 0; f < 4; f++) {
frag_c_ptr[k * 4 + f] += sh_c_ptr[f];
}
}
}
if (!last) {
int4* frag_c_ptr = reinterpret_cast<int4*>(&frag_c);
#pragma unroll
for (int k = 0; k < th_size; k++) {
if constexpr (m_block_size_8) {
if (k % 2) continue;
} else {
if (k / 8 * 16 + (threadIdx.x % 32) / 4 >= block_num_valid_tokens)
continue;
}
C_tmp[c_cur_offset + active_threads * k + threadIdx.x] = frag_c_ptr[k];
}
}
};
// Write out the reduce final result in the correct layout. We only actually
// reshuffle matrix fragments in this step, the reduction above is performed
// in fragment layout.
auto write_result = [&]() {
int c_gl_stride = prob_n / 8;
constexpr int c_sh_stride = 2 * thread_n_blocks + 1;
int c_gl_wr_delta = c_gl_stride * (threads / (2 * thread_n_blocks));
constexpr int c_sh_rd_delta =
c_sh_stride * (threads / (2 * thread_n_blocks));
int c_gl_wr = c_gl_stride * (threadIdx.x / (2 * thread_n_blocks)) +
(threadIdx.x % (2 * thread_n_blocks));
c_gl_wr += (2 * thread_n_blocks) * slice_col;
int c_sh_wr;
if constexpr (m_block_size_8) {
c_sh_wr = (8 * c_sh_stride) * ((threadIdx.x % 32) % 4 * 2) +
(threadIdx.x % 32) / 4;
c_sh_wr += 64 * (threadIdx.x / 32);
} else {
c_sh_wr =
(4 * c_sh_stride) * ((threadIdx.x % 32) / 4) + (threadIdx.x % 32) % 4;
c_sh_wr += 32 * (threadIdx.x / 32);
}
int c_sh_rd = c_sh_stride * (threadIdx.x / (2 * thread_n_blocks)) +
(threadIdx.x % (2 * thread_n_blocks));
// We first reorder in shared memory to guarantee the most efficient final
// global write patterns
auto write = [&](int idx, float c0, float c1, FragS& s) {
scalar_t2 res =
Dtype::nums2num2(Dtype::float2num(c0), Dtype::float2num(c1));
// For per-column quantization we finally apply the scale here (only for
// 4-bit)
if constexpr (!has_act_order && group_blocks == -1 &&
w_type.size_bits() == 4 && !has_zp) {
res = __hmul2(res, s[0]);
}
if constexpr (m_block_size_8) {
((scalar_t*)sh_red)[idx] = res.x;
((scalar_t*)sh_red)[idx + 8 * c_sh_stride] = res.y;
} else {
((scalar_t2*)sh_red)[idx] = res;
}
};
if (threadIdx.x / 32 < thread_n_blocks / 4) {
#pragma unroll
for (int i = 0; i < thread_m_blocks; i++) {
#pragma unroll
for (int j = 0; j < 4; j++) {
if constexpr (m_block_size_8) {
int wr = c_sh_wr + 16 * j;
write(wr, frag_c[i][j][0][0], frag_c[i][j][0][1],
frag_s[j / 2][2 * (j % 2) + 0]);
write(wr + 8, frag_c[i][j][0][2], frag_c[i][j][0][3],
frag_s[j / 2][2 * (j % 2) + 1]);
} else {
int wr = c_sh_wr + 8 * j;
write(wr + (4 * c_sh_stride) * 0 + 0, frag_c[i][j][0][0],
frag_c[i][j][0][1], frag_s[j / 2][2 * (j % 2) + 0]);
write(wr + (4 * c_sh_stride) * 8 + 0, frag_c[i][j][0][2],
frag_c[i][j][0][3], frag_s[j / 2][2 * (j % 2) + 0]);
write(wr + (4 * c_sh_stride) * 0 + 4, frag_c[i][j][1][0],
frag_c[i][j][1][1], frag_s[j / 2][2 * (j % 2) + 1]);
write(wr + (4 * c_sh_stride) * 8 + 4, frag_c[i][j][1][2],
frag_c[i][j][1][3], frag_s[j / 2][2 * (j % 2) + 1]);
}
}
c_sh_wr += 16 * (4 * c_sh_stride);
}
}
__syncthreads();
#pragma unroll
for (int i = 0;
i < div_ceil(16 * thread_m_blocks, threads / (2 * thread_n_blocks));
i++) {
int row = c_gl_wr / c_gl_stride;
if (row < block_num_valid_tokens) {
int64_t sorted_row = sh_block_sorted_ids[row];
int64_t true_idx = sorted_row * c_gl_stride + c_gl_wr % c_gl_stride;
scalar_t2 topk_weight_score;
if (mul_topk_weights) topk_weight_score = sh_block_topk_weights[row];
if (use_atomic_add && slice_count > 1 || mul_topk_weights) {
scalar_t2* C_half2 = reinterpret_cast<scalar_t2*>(&C[true_idx]);
scalar_t2* sh_red_half2 =
reinterpret_cast<scalar_t2*>(&sh_red[c_sh_rd]);
#pragma unroll
for (int a = 0; a < 4; a++) {
scalar_t2 res = sh_red_half2[a];
if (mul_topk_weights) {
res = __hmul2(res, topk_weight_score);
}
if (use_atomic_add && slice_count > 1) {
atomicAdd(&C_half2[a], res);
} else {
C_half2[a] = res;
};
}
} else {
C[true_idx] = sh_red[c_sh_rd];
}
c_gl_wr += c_gl_wr_delta;
c_sh_rd += c_sh_rd_delta;
}
}
__syncthreads();
};
// Start global fetch and register load pipelines.
auto start_pipes = [&]() {
#pragma unroll
for (int i = 0; i < stages - 1; i++) {
if (has_act_order && i == 0) {
int last_g_idx = slice_k_start + stages * tb_k * 2;
if (last_g_idx >= prob_k) {
last_g_idx = prob_k - 1;
}
fetch_act_order_scales_to_shared(true, g_idx[slice_k_start],
g_idx[last_g_idx]);
}
if constexpr (has_zp && !is_zp_float && group_blocks == -1) {
if (i == 0) {
fetch_col_zp_to_shared();
fetch_col_scale_to_shared();
}
}
fetch_to_shared(i, i, i < slice_iters);
}
zero_accums();
wait_for_stage();
init_same_group(0);
fetch_to_registers(0, 0);
fetch_scales_to_registers(0, 0);
fetch_zp_to_registers(0, 0);
a_gl_rd += a_gl_rd_delta_o * (stages - 1);
slice_k_start_shared_fetch += tb_k * (stages - 1);
};
if (slice_iters) {
start_pipes();
}
// Main loop.
while (slice_iters) {
// We unroll over both the global fetch and the register load pipeline to
// ensure all shared memory accesses are static. Note that both pipelines
// have even length meaning that the next iteration will always start at
// index 0.
#pragma unroll
for (int pipe = 0; pipe < stages;) {
#pragma unroll
for (int k = 0; k < b_sh_wr_iters; k++) {
fetch_to_registers(k + 1, pipe % stages);
fetch_scales_to_registers(k + 1, pipe);
fetch_zp_to_registers(k + 1, pipe);
if (k == b_sh_wr_iters - 2) {
fetch_to_shared((pipe + stages - 1) % stages, pipe,
slice_iters >= stages);
pipe++;
wait_for_stage();
init_same_group(pipe % stages);
}
matmul(k);
}
slice_iters--;
if (slice_iters == 0) {
break;
}
}
a_remaining_load_count_in_slice = 0;
a_gl_rd += a_gl_rd_delta_o * stages;
slice_k_start += tb_k * stages;
slice_k_start_shared_fetch += tb_k * stages;
if constexpr (has_act_order) {
int first_group_id = g_idx[slice_k_start];
int last_g_idx = slice_k_start + stages * tb_k * 2;
if (last_g_idx >= prob_k) {
last_g_idx = prob_k - 1;
}
int last_group_id = g_idx[last_g_idx];
if (last_group_id >= sh_first_group_id + sh_num_groups) {
fetch_act_order_scales_to_shared(false, first_group_id, last_group_id);
__syncthreads();
}
}
// Process results and, if necessary, proceed to the next column slice.
// While this pattern may not be the most readable, other ways of writing
// the loop seemed to noticeably worse performance after compilation.
if (slice_iters == 0) {
cp_async_wait<0>();
bool last = slice_idx == slice_count - 1;
// For per-column scales, we only fetch them here in the final step before
// write-out
if constexpr (!has_act_order && group_blocks == -1 && !has_zp) {
if (w_type.size_bits() == 8 || (last || use_atomic_add)) {
if (s_sh_wr_pred) {
cp_async4(&sh_s[s_sh_wr], &scales_ptr[s_gl_rd]);
}
cp_async_fence();
}
}
thread_block_reduce();
if constexpr (!has_act_order && group_blocks == -1 && !has_zp) {
if (w_type.size_bits() == 8 || (last || use_atomic_add)) {
cp_async_wait<0>();
__syncthreads();
if (threadIdx.x / 32 < thread_n_blocks / 4) {
reinterpret_cast<int4*>(&frag_s)[0] = sh_s[s_sh_rd + 0];
reinterpret_cast<int4*>(&frag_s)[1] = sh_s[s_sh_rd + 4];
if constexpr (m_block_size_8) {
int idx = (threadIdx.x / 4) % 2;
scalar_t2* frag_s_half2 = reinterpret_cast<scalar_t2*>(frag_s);
#pragma unroll
for (int i = 0; i < 8; i++) {
frag_s_half2[i] = Dtype::num2num2(
reinterpret_cast<scalar_t*>(&frag_s_half2[i])[idx]);
}
}
}
}
}
// For 8-bit channelwise, we apply the scale before the global reduction
// that converts the fp32 results to fp16 (so that we avoid possible
// overflow in fp16)
if constexpr (!has_act_order && group_blocks == -1 &&
w_type.size_bits() == 8 && !has_zp) {
if (threadIdx.x / 32 < thread_n_blocks / 4) {
#pragma unroll
for (int i = 0; i < thread_m_blocks; i++) {
#pragma unroll
for (int j = 0; j < 4; j++) {
scale_float<scalar_t>(
reinterpret_cast<float*>(&frag_c[i][j][0][0]),
frag_s[j / 2][2 * (j % 2) + 0]);
scale_float<scalar_t>(
reinterpret_cast<float*>(&frag_c[i][j][0][2]),
frag_s[j / 2][2 * (j % 2) + (m_block_size_8 ? 1 : 0)]);
if constexpr (!m_block_size_8) {
scale_float<scalar_t>(
reinterpret_cast<float*>(&frag_c[i][j][1][0]),
frag_s[j / 2][2 * (j % 2) + 1]);
scale_float<scalar_t>(
reinterpret_cast<float*>(&frag_c[i][j][1][2]),
frag_s[j / 2][2 * (j % 2) + 1]);
}
}
}
}
}
if (slice_count > 1 && !use_atomic_add) {
// only globally reduce if there is more than one block in a slice
barrier_acquire(&locks[locks_off], slice_idx);
if (use_fp32_reduce) {
global_reduce_fp32(slice_idx == 0, last);
} else {
global_reduce_fp16(slice_idx == 0, last);
}
barrier_release(&locks[locks_off], last);
}
if (use_atomic_add && slice_count > 1 && slice_idx != 0)
wait_negative_and_add(&locks[locks_off]);
if (last || use_atomic_add)
// only the last block in a slice actually writes the result
write_result();
if (slice_row) a_remaining_load_count_in_slice = stages;
slice_row = 0;
slice_col_par++;
slice_col++;
is_first_matmul_in_slice = true;
init_slice();
if (slice_iters) {
a_gl_rd = a_gl_stride * (threadIdx.x / a_gl_rd_delta_o) +
(threadIdx.x % a_gl_rd_delta_o);
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++)
B_ptr[i] += b_sh_stride - b_gl_rd_delta_o * k_tiles;
if (slice_col == 0) {
#pragma unroll
for (int i = 0; i < b_sh_wr_iters; i++) B_ptr[i] -= b_gl_stride;
}
// Update slice k/n for scales loading
if constexpr (has_act_order) {
slice_k_start = tb_k * slice_row;
slice_k_finish = slice_k_start + tb_k * slice_iters;
slice_k_start_shared_fetch = slice_k_start;
slice_n_offset = act_s_col_tb_stride * slice_col;
} else {
s_gl_rd = s_sh_stride * slice_col + threadIdx.x;
zp_gl_rd = zp_sh_stride * slice_col + threadIdx.x;
}
start_pipes();
}
}
}
}
} // namespace MARLIN_NAMESPACE_NAME
#endif