Files
kernels/tests/regression/sgemm_tcore/kernel.cpp
Hansung Kim 18e3653d31 sgemm_tcore: Increase RF data reuse for WMITER/WNITER
... by splitting vx_wmma_load to vx_wmma_load_{a,b} and pulling it
out of the innermost loop.

TODO: there's some duplicate address compute being done in the both
functions.
2024-06-03 21:10:42 -07:00

574 lines
22 KiB
C++

#define RISCV_CUSTOM3 0x7B
#include <stdint.h>
#include <vx_intrinsics.h>
#include <vx_print.h>
#include <vx_spawn.h>
#include "common.h"
#define NUM_LANES 8
#define USE_TENSOR_CORE 1
#define TC_SINGLE_WARP 0
// number of loop around the inner 0..TCK..BK loop to simulate perfect-DRAM
// scenario
#define BK_LOOP 1
#define TRANSPOSE_AS 1
// Constraints on parameters:
// * Memory:
// (BM + BN) * BK * sizeof(float) <= sharedmem size.
// BM * BK == BN * BK >= threadblock size >= NT * CORES_PER_CLUSTER
// When larger, the kernel runs a sequential loop to read into sharedmem;
// but smaller case is not handled.
// * Compute:
// ( M* N) / (TM*TN) == grid size >= NC*NW*NT
// (BM*BN) / (TM*TN) == threadblock size < NT * NW * CORES_PER_CLUSTER
// (BM*BN) / (TM*TN) == threadblock size >= NT * CORES_PER_CLUSTER
// * Combining BM * BK >= (BM*BN) / (TM*TN) == threadblock yields
// BM <= BK*TM*TN
#define BM 32
#define BN 32
#define BK 32
#define WM 16
#define WN 8
#define TCM 8
#define TCN 8
#define TCK 8
#define WMITER (WM / TCM)
#define WNITER (WN / TCN)
#if USE_TENSOR_CORE == 1
#define TM 1
#define TN ((TCM * TCN) / NUM_LANES / TM)
#else
#define TM 1
#define TN 1
#endif
#define ELEM_PER_THREAD (WMITER * WNITER * TM * TN)
inline constexpr void map_operand_32lanes(const int tid, int &row, int &col) {
const int tg = tid / 4;
// A (row major)
// Figure 7(a) in paper
// row 0~ 3: threadgroups 0 and 2
// row 4~ 7: threadgroups 4 and 6
// row 8~11: threadgroups 1 and 3
// row 12~15: threadgroups 5 and 7
row = tid % 4;
row += (tg * 8) % 16;
row += (tg / 4) * 4;
// B (column major)
// NOTE: Matrix B mapping in Figure 7(a) is incorrect; below is the
// corrected mapping:
// col 0~ 3: threadgroups 0 and 1
// col 4~ 7: threadgroups 4 and 5
// col 8~11: threadgroups 2 and 3
// col 12~15: threadgroups 6 and 7
col = tid % 4;
col += ((tg % 4) / 2) * 8;
col += (tg / 4) * 4;
}
inline constexpr void map_operand_8lanes(const int tid, int &row, int &col) {
const int tg = tid / 4;
// A (row major)
// row 0~ 3: threadgroup 0
// row 4~ 7: threadgroup 1
row = tid % 4;
row += tg * 4;
// B (column major)
// col 0~ 3: threadgroup 0
// col 4~ 7: threadgroup 1
col = tid % 4;
col += tg * 4;
}
inline constexpr void map_operand(const int tid, int &row, int &col) {
if constexpr (NUM_LANES == 32) {
map_operand_32lanes(tid, row, col);
} else if constexpr (NUM_LANES == 8) {
map_operand_8lanes(tid, row, col);
} else {
// FIXME: not allowed
}
}
inline constexpr void map_c_32lanes(const int tid, int &row, int &col) {
const int tg = tid / 4;
// C
// Figure 7(b), left
col = ((tg % 4) / 2) * 8;
row = (tg * 8) % 16;
row += (tg / 4) * 4;
// Figure 7(b), right
row += (tid % 4) % 2;
col += ((tid % 4) / 2) * 2;
}
inline constexpr void map_c_8lanes(const int tid, int &row, int &col) {
const int tg = tid / 4;
// C
col = 0;
row = tg * 4;
// Figure 7(b), right
row += (tid % 4) % 2;
col += ((tid % 4) / 2) * 2;
}
inline constexpr void map_c(const int tid, int &row, int &col) {
if constexpr (NUM_LANES == 32) {
map_c_32lanes(tid, row, col);
} else if constexpr (NUM_LANES == 8) {
map_c_8lanes(tid, row, col);
} else {
// FIXME: not allowed
}
}
inline void vx_wmma(const int dest_reg) {
if (dest_reg == 0) {
asm volatile (".insn r %0, 0, 0, x0, x0, x0" :: "i"(RISCV_CUSTOM3));
} else {
asm volatile (".insn r %0, 0, 0, x1, x0, x0" :: "i"(RISCV_CUSTOM3));
}
}
// `local_k` is assumed to be multiple of TCK
inline void vx_wmma_load_a(volatile float *smem_A, const int local_k,
const int warp_row, const int wm_iter, const int thread_in_warp) {
const int tid = thread_in_warp;
const int tg = tid / 4;
// TODO: this is duplicately computed between vx_wmma_load_a and vx_wmma_load_b
int row = 0;
int col = 0;
map_operand(tid, row, col);
constexpr int smem_A_rows = BM;
constexpr int smem_A_cols = BK;
constexpr int smem_AS_rows = BK;
constexpr int smem_AS_cols = BM;
constexpr int smem_B_rows = BK;
constexpr int smem_B_cols = BN;
if constexpr (!TRANSPOSE_AS) {
int A_offset = (WM * warp_row + TCM * wm_iter + row) * smem_A_cols;
// @perf: bank conflicts
// f8-f15 stores a single row of A
asm volatile("flw f0, %0" ::"m"(smem_A[A_offset + (local_k + 0)]));
asm volatile("flw f1, %0" ::"m"(smem_A[A_offset + (local_k + 1)]));
asm volatile("flw f2, %0" ::"m"(smem_A[A_offset + (local_k + 2)]));
asm volatile("flw f3, %0" ::"m"(smem_A[A_offset + (local_k + 3)]));
asm volatile("flw f4, %0" ::"m"(smem_A[A_offset + (local_k + 4)]));
asm volatile("flw f5, %0" ::"m"(smem_A[A_offset + (local_k + 5)]));
asm volatile("flw f6, %0" ::"m"(smem_A[A_offset + (local_k + 6)]));
asm volatile("flw f7, %0" ::"m"(smem_A[A_offset + (local_k + 7)]));
} else {
// transposed A
// f8-f15 stores a single row of A
asm volatile("flw f0, %0" ::"m"(smem_A[((local_k + 0) * smem_AS_cols) + (WM * warp_row + TCM * wm_iter) + row]));
asm volatile("flw f1, %0" ::"m"(smem_A[((local_k + 1) * smem_AS_cols) + (WM * warp_row + TCM * wm_iter) + row]));
asm volatile("flw f2, %0" ::"m"(smem_A[((local_k + 2) * smem_AS_cols) + (WM * warp_row + TCM * wm_iter) + row]));
asm volatile("flw f3, %0" ::"m"(smem_A[((local_k + 3) * smem_AS_cols) + (WM * warp_row + TCM * wm_iter) + row]));
asm volatile("flw f4, %0" ::"m"(smem_A[((local_k + 4) * smem_AS_cols) + (WM * warp_row + TCM * wm_iter) + row]));
asm volatile("flw f5, %0" ::"m"(smem_A[((local_k + 5) * smem_AS_cols) + (WM * warp_row + TCM * wm_iter) + row]));
asm volatile("flw f6, %0" ::"m"(smem_A[((local_k + 6) * smem_AS_cols) + (WM * warp_row + TCM * wm_iter) + row]));
asm volatile("flw f7, %0" ::"m"(smem_A[((local_k + 7) * smem_AS_cols) + (WM * warp_row + TCM * wm_iter) + row]));
// #pragma GCC unroll 8
// for (int i = 0; i < 8; i++) {
// asm volatile("flw f0, %0" ::"m"(smem_A[((local_k + i) * smem_A_rows) + (WM * warp_row + TCM * wm_iter) + row]));
// }
}
}
// `local_k` is assumed to be multiple of TCK
inline void vx_wmma_load_b(volatile float *smem_B, const int local_k,
const int warp_col, const int wn_iter,
const int thread_in_warp) {
const int tid = thread_in_warp;
const int tg = tid / 4;
int row = 0;
int col = 0;
map_operand(tid, row, col);
constexpr int smem_A_rows = BM;
constexpr int smem_A_cols = BK;
constexpr int smem_AS_rows = BK;
constexpr int smem_AS_cols = BM;
constexpr int smem_B_rows = BK;
constexpr int smem_B_cols = BN;
// f8-f15 stores a single column of B
asm volatile("flw f8, %0" ::"m"(smem_B[((local_k + 0) * smem_B_cols) + (WN * warp_col + TCN * wn_iter) + col]));
asm volatile("flw f9, %0" ::"m"(smem_B[((local_k + 1) * smem_B_cols) + (WN * warp_col + TCN * wn_iter) + col]));
asm volatile("flw f10, %0" ::"m"(smem_B[((local_k + 2) * smem_B_cols) + (WN * warp_col + TCN * wn_iter) + col]));
asm volatile("flw f11, %0" ::"m"(smem_B[((local_k + 3) * smem_B_cols) + (WN * warp_col + TCN * wn_iter) + col]));
asm volatile("flw f12, %0" ::"m"(smem_B[((local_k + 4) * smem_B_cols) + (WN * warp_col + TCN * wn_iter) + col]));
asm volatile("flw f13, %0" ::"m"(smem_B[((local_k + 5) * smem_B_cols) + (WN * warp_col + TCN * wn_iter) + col]));
asm volatile("flw f14, %0" ::"m"(smem_B[((local_k + 6) * smem_B_cols) + (WN * warp_col + TCN * wn_iter) + col]));
asm volatile("flw f15, %0" ::"m"(smem_B[((local_k + 7) * smem_B_cols) + (WN * warp_col + TCN * wn_iter) + col]));
}
inline void initialize_C(const int dest_reg) {
// initialize C to zeros
if (dest_reg == 0) {
asm volatile("fmv.w.x f16, x0");
asm volatile("fmv.w.x f17, x0");
asm volatile("fmv.w.x f18, x0");
asm volatile("fmv.w.x f19, x0");
asm volatile("fmv.w.x f20, x0");
asm volatile("fmv.w.x f21, x0");
asm volatile("fmv.w.x f22, x0");
asm volatile("fmv.w.x f23, x0");
} else {
asm volatile("fmv.w.x f24, x0");
asm volatile("fmv.w.x f25, x0");
asm volatile("fmv.w.x f26, x0");
asm volatile("fmv.w.x f27, x0");
asm volatile("fmv.w.x f28, x0");
asm volatile("fmv.w.x f29, x0");
asm volatile("fmv.w.x f30, x0");
asm volatile("fmv.w.x f31, x0");
}
}
inline void write_results(volatile float *local_warp_results,
const int thread_in_warp, const int warp_col,
const int warp_row, const int wn_iter,
const int wm_iter, const int dim_m, const int dim_n,
float *C, const int threadblock_id_x,
const int threadblock_id_y) {
int tid = thread_in_warp;
int tg = tid / 4;
// these are [0, TCM/TCN)
int tid_row = 0;
int tid_col = 0;
map_c(tid, tid_row, tid_col);
int local_row = (WM * warp_row + TCM * wm_iter) + tid_row;
int local_col = (WN * warp_col + TCN * wn_iter) + tid_col;
float *global_offset_C = C +
(BM * threadblock_id_y) * dim_n +
BN * threadblock_id_x;
// @perf: this likely causes a lot of gmem bank conflicts
if (wm_iter == 0) {
asm volatile ("fsw f16, %0" :: "m"(global_offset_C[dim_n * (local_row + 0) + (local_col + 0)]));
asm volatile ("fsw f17, %0" :: "m"(global_offset_C[dim_n * (local_row + 0) + (local_col + 1)]));
asm volatile ("fsw f18, %0" :: "m"(global_offset_C[dim_n * (local_row + 2) + (local_col + 0)]));
asm volatile ("fsw f19, %0" :: "m"(global_offset_C[dim_n * (local_row + 2) + (local_col + 1)]));
asm volatile ("fsw f20, %0" :: "m"(global_offset_C[dim_n * (local_row + 0) + (local_col + 4)]));
asm volatile ("fsw f21, %0" :: "m"(global_offset_C[dim_n * (local_row + 0) + (local_col + 5)]));
asm volatile ("fsw f22, %0" :: "m"(global_offset_C[dim_n * (local_row + 2) + (local_col + 4)]));
asm volatile ("fsw f23, %0" :: "m"(global_offset_C[dim_n * (local_row + 2) + (local_col + 5)]));
} else {
asm volatile ("fsw f24, %0" :: "m"(global_offset_C[dim_n * (local_row + 0) + (local_col + 0)]));
asm volatile ("fsw f25, %0" :: "m"(global_offset_C[dim_n * (local_row + 0) + (local_col + 1)]));
asm volatile ("fsw f26, %0" :: "m"(global_offset_C[dim_n * (local_row + 2) + (local_col + 0)]));
asm volatile ("fsw f27, %0" :: "m"(global_offset_C[dim_n * (local_row + 2) + (local_col + 1)]));
asm volatile ("fsw f28, %0" :: "m"(global_offset_C[dim_n * (local_row + 0) + (local_col + 4)]));
asm volatile ("fsw f29, %0" :: "m"(global_offset_C[dim_n * (local_row + 0) + (local_col + 5)]));
asm volatile ("fsw f30, %0" :: "m"(global_offset_C[dim_n * (local_row + 2) + (local_col + 4)]));
asm volatile ("fsw f31, %0" :: "m"(global_offset_C[dim_n * (local_row + 2) + (local_col + 5)]));
}
}
inline void threadblock_barrier(unsigned int tid_in_threadblock,
unsigned int barrier_id, unsigned int count) {
vx_fence();
vx_barrier(barrier_id, count);
}
inline void
global_dmem_load(const uint32_t dim_n, const uint32_t dim_k, const uint32_t k,
const float *A, const float *B, volatile float *local_a,
volatile float *local_b, const uint32_t threadblock_id_x,
const uint32_t threadblock_id_y, const uint32_t local_a_row,
const uint32_t local_a_col, const uint32_t local_as_row,
const uint32_t local_as_col, const uint32_t local_b_row,
const uint32_t local_b_col) {
// Data move from GMEM to SMEM
//
// Make sure global offset values for A and B are contiguous between
// neighboring threads to ensure GMEM coalescing.
//
// TODO: Sharedmem swizzling is important here
if constexpr (!TRANSPOSE_AS) {
const uint32_t global_a_row = BM * threadblock_id_y + local_a_row;
// number of rows a full TB can read at a time
constexpr uint32_t row_stride_a = (BM * BN) / ELEM_PER_THREAD / BK;
#pragma GCC unroll 1
for (uint32_t local_row_offset = 0; local_row_offset < BM;
local_row_offset += row_stride_a) {
const uint32_t global_a_offset =
dim_k * (global_a_row + local_row_offset) + (k + local_a_col);
// NOTE: all threads in TB will do this load; make sure this is not
// out-of-bounds of BM*BK
local_a[BK * (local_a_row + local_row_offset) + local_a_col] =
A[global_a_offset];
}
} else {
const uint32_t global_a_row = BM * threadblock_id_y + local_as_col;
// const uint32_t global_a_row = BM * threadblock_id_y + local_as_row;
constexpr uint32_t row_stride_as = (BM * BN) / ELEM_PER_THREAD / BM;
#pragma GCC unroll 1
for (uint32_t local_row_offset = 0; local_row_offset < BK;
local_row_offset += row_stride_as) {
// @perf: bank conflicts here
const uint32_t global_a_offset =
dim_k * (global_a_row) + (k + local_as_row + local_row_offset);
// FIXME experimenting with global coalescing
// const uint32_t global_a_offset =
// dim_k * (global_a_row + local_row_offset) + (k + local_as_col);
local_a[BM * (local_as_row + local_row_offset) + local_as_col] =
A[global_a_offset];
}
}
constexpr uint32_t row_stride_b = (BM * BN) / ELEM_PER_THREAD / BN;
const uint32_t global_b_col = BN * threadblock_id_x + local_b_col;
#pragma GCC unroll 1
for (uint32_t load_offset = 0; load_offset < BK;
load_offset += row_stride_b) {
const uint32_t global_b_offset =
dim_n * (k + local_b_row + load_offset) + global_b_col;
local_b[BN * (local_b_row + load_offset) + local_b_col] =
B[global_b_offset];
}
}
void thread_block_gemm(kernel_arg_t *__UNIFORM__ arg,
const uint32_t tid_in_threadblock,
const uint32_t threadblock_dim_x,
const uint32_t threadblock_dim_y,
const uint32_t threadblock_id_x,
const uint32_t threadblock_id_y,
const uint32_t threadblock_id_in_cluster,
float *sharedmem_per_threadblock) {
const float *A = (const float *)arg->addr_a;
const float *B = (const float *)arg->addr_b;
float *C = (float *)arg->addr_c;
const uint32_t dim_m = arg->dim_m;
const uint32_t dim_n = arg->dim_n;
const uint32_t dim_k = arg->dim_k;
const uint32_t local_a_row = tid_in_threadblock / BK;
const uint32_t local_a_col = tid_in_threadblock % BK;
const uint32_t local_as_row = tid_in_threadblock / BM;
const uint32_t local_as_col = tid_in_threadblock % BM;
const uint32_t local_b_row = tid_in_threadblock / BN;
const uint32_t local_b_col = tid_in_threadblock % BN;
const uint32_t local_c_row = tid_in_threadblock / (BN / TN);
const uint32_t local_c_col = tid_in_threadblock % (BN / TN);
// each thread generates TM output element
float reg_c[TM * TN] = { 0.0f };
float reg_a[TM] = { 0.0f };
float reg_b[TN] = { 0.0f };
const uint32_t warp_in_threadblock = tid_in_threadblock / NUM_LANES;
const uint32_t warp_row = warp_in_threadblock / (BN / WN);
const uint32_t warp_col = warp_in_threadblock % (BN / WN);
const uint32_t tid_in_warp = tid_in_threadblock % NUM_LANES;
volatile float *local_a = sharedmem_per_threadblock;
// const size_t local_a_elems = threadblock_dim_x * threadblock_dim_y;
const size_t local_a_elems = (BM * BK);
volatile float *local_b = sharedmem_per_threadblock + local_a_elems;
const size_t local_b_elems = (BK * BN);
volatile float *local_warp_results =
local_b + local_b_elems + (warp_in_threadblock * TCM * TCN);
// clear out C
initialize_C(0);
initialize_C(1);
#pragma GCC unroll 1
for (uint32_t k = 0; k < dim_k; k += BK) {
global_dmem_load(dim_n, dim_k, k, A, B, local_a, local_b,
threadblock_id_x, threadblock_id_y, local_a_row,
local_a_col, local_as_row, local_as_col, local_b_row,
local_b_col);
threadblock_barrier(tid_in_threadblock, threadblock_id_in_cluster,
threadblock_dim_y);
#if USE_TENSOR_CORE
// @perf: this loop spills to stack a lot because of all the flws in
// vx_wmma_load
#pragma GCC unroll 1
for (int i = 0; i < BK_LOOP; i++) {
#pragma GCC unroll 1
for (uint32_t local_k = 0; local_k < BK; local_k += TCK) {
// perform wmma
// vx_wmma_load(local_a, local_b, warp_x, warp_y, tid_in_warp);
// FIXME: this is wrong!! need separate accumulation register for
// WM/WN_ITERS
#pragma GCC unroll 2
for (int wn_iter = 0; wn_iter < WNITER; wn_iter++) {
vx_wmma_load_b(local_b, local_k, warp_col, wn_iter, tid_in_warp);
// vx_wmma_load_b(local_b, 0, 0, 0, tid_in_warp);
#pragma GCC unroll 2
for (int wm_iter = 0; wm_iter < WMITER; wm_iter++) {
#if TC_SINGLE_WARP
if (warp_in_threadblock == 0) {
#endif
// if ((threadblock_id_in_cluster % 2) == 0) {
// asm volatile("addi a0, a0, 0");
// asm volatile("addi a0, a0, 0");
// asm volatile("addi a0, a0, 0");
// asm volatile("addi a0, a0, 0");
// asm volatile("addi a0, a0, 0");
// asm volatile("addi a0, a0, 0");
// asm volatile("addi a0, a0, 0");
// asm volatile("addi a0, a0, 0");
// asm volatile("addi a0, a0, 0");
// }
// SMEM -> RF
vx_wmma_load_a(local_a, local_k, warp_row, wm_iter, tid_in_warp);
// vx_wmma_load_a(local_a, 0, 0, 0, tid_in_warp);
// compute
vx_wmma(wm_iter);
#if TC_SINGLE_WARP
}
#endif
}
}
}
}
threadblock_barrier(tid_in_threadblock, threadblock_id_in_cluster,
threadblock_dim_y);
#else
// Compute single tile*tile matmul
#pragma GCC unroll 4
for (uint32_t local_k = 0; local_k < BK; local_k++) {
// First, pump data from SMEM->RF
#pragma GCC unroll TM
for (uint32_t res_idx_m = 0; res_idx_m < TM; res_idx_m++) {
reg_a[res_idx_m] =
local_a[BK * (TM * local_c_row + res_idx_m) + local_k];
}
#pragma GCC unroll TN
for (uint32_t res_idx_n = 0; res_idx_n < TN; res_idx_n++) {
reg_b[res_idx_n] =
local_b[BN * local_k + (TN * local_c_col + res_idx_n)];
}
// Next, compute multiple result elements (TM*TN) by reusing data in RF
#pragma GCC unroll TM
for (uint32_t res_idx_m = 0; res_idx_m < TM; res_idx_m++) {
#pragma GCC unroll TN
for (uint32_t res_idx_n = 0; res_idx_n < TN; res_idx_n++) {
// NOTE use of local_b_row
reg_c[TN * res_idx_m + res_idx_n] +=
reg_a[res_idx_m] * reg_b[res_idx_n];
// reg_c[TN * res_idx_m + res_idx_n] +=
// local_a[BK * (TM * local_c_row + res_idx_m) + local_k] *
// local_b[BN * local_k + (TN * local_c_col + res_idx_n)];
}
}
}
threadblock_barrier(tid_in_threadblock, threadblock_id_in_cluster,
threadblock_dim_y);
#endif
}
#if USE_TENSOR_CORE
#pragma GCC unroll 1
for (int wm_iter = 0; wm_iter < WMITER; wm_iter++) {
#pragma GCC unroll 1
for (int wn_iter = 0; wn_iter < WNITER; wn_iter++) {
#if TC_SINGLE_WARP
if (warp_in_threadblock == 0) {
#endif
write_results(local_warp_results, tid_in_warp, warp_col, warp_row,
wn_iter, wm_iter, dim_m, dim_n, C, threadblock_id_x,
threadblock_id_y);
#if TC_SINGLE_WARP
}
#endif
}
}
#else
// Store result data from RF to GMEM
#pragma GCC unroll TM
for (uint32_t res_idx_m = 0; res_idx_m < TM; res_idx_m++) {
#pragma GCC unroll TN
for (uint32_t res_idx_n = 0; res_idx_n < TN; res_idx_n++) {
C[dim_n * (BM * threadblock_id_y + TM * local_c_row + res_idx_m) +
(BN * threadblock_id_x + TN * local_c_col + res_idx_n)] =
reg_c[TN * res_idx_m + res_idx_n];
}
}
#endif
}
void kernel_body(int task_id, kernel_arg_t *__UNIFORM__ arg) {
// @perf: All threads are running these compute whose result is mostly same
// across the threadblock
const uint32_t threads_per_threadblock = (BM * BN) / (ELEM_PER_THREAD);
#ifdef RADIANCE
const uint32_t threadblocks_per_core = CORES_PER_CLUSTER * vx_num_threads() *
vx_num_warps() /
threads_per_threadblock;
#else
const uint32_t threadblocks_per_core =
vx_num_threads() * vx_num_warps() / threads_per_threadblock;
#endif
const uint32_t threadblock_dim_x = vx_num_threads();
const uint32_t threadblock_dim_y = vx_num_warps() / threadblocks_per_core;
const int threadblock_id = task_id / threads_per_threadblock;
const int threadblock_id_in_cluster = threadblock_id % threadblocks_per_core;
const int tid_in_threadblock = task_id % threads_per_threadblock;
const uint32_t dim_m = arg->dim_m;
const uint32_t dim_n = arg->dim_n;
const uint32_t dim_n_in_blocks = dim_n / BN;
const int threadblock_id_x = threadblock_id % dim_n_in_blocks;
const int threadblock_id_y = threadblock_id / dim_n_in_blocks;
// "static" shared memory allocation. This would determine threadblock
// occupancy of a single cluster
float *sharedmem_per_threadblock =
(float *)DEV_SMEM_START_ADDR + (2 * BM * BK) * threadblock_id_in_cluster;
thread_block_gemm(arg, tid_in_threadblock, threadblock_dim_x,
threadblock_dim_y, threadblock_id_x, threadblock_id_y,
threadblock_id_in_cluster, sharedmem_per_threadblock);
}
int main() {
kernel_arg_t *arg = (kernel_arg_t *)KERNEL_ARG_DEV_MEM_ADDR;
const uint32_t grid_size = arg->dim_m * arg->dim_n / ELEM_PER_THREAD;
#ifdef RADIANCE
vx_spawn_tasks_cluster(grid_size, (vx_spawn_tasks_cb)kernel_body, arg);
#else
// NOTE: This kernel assumes contiguous thread scheduling for efficient shared
// memory allocation, and therefore does not work with original vx_spawn_tasks
vx_spawn_tasks_contiguous(grid_size, (vx_spawn_tasks_cb)kernel_body, arg);
#endif
return 0;
}