[CODEGEN] Now padding shared memory for layout conversion (#468)

This commit is contained in:
Philippe Tillet
2022-03-03 22:19:05 -08:00
committed by GitHub
parent d9dd97492f
commit bb5765df5c
4 changed files with 62 additions and 35 deletions

View File

@@ -103,6 +103,7 @@ public:
int shape_per_cta(size_t k) { return shape_per_cta_.at(k); }
int rep_per_cta(size_t k) { return shape_[k] / shape_per_cta_[k]; }
virtual int contig_per_thread(size_t k) = 0;
protected:
std::vector<int> shape_per_cta_;
@@ -181,6 +182,7 @@ public:
int wpt(size_t k) { return wpt_.at(k); }
int spw(size_t k) { return spw_.at(k); }
int rep(size_t k) { return rep_.at(k); }
int contig_per_thread(size_t k) { return contig_per_thread_.at(k); }
// helpers for generator.cc
std::string get_ptx_instr() const { return mma_instr_ptx_.at(tensor_core_type_); }
@@ -203,6 +205,8 @@ private:
std::vector<int> spt_;
// repetitions
std::vector<int> rep_;
// contiguous per thread
std::vector<int> contig_per_thread_;
TensorCoreType tensor_core_type_ = FP32_FP16_FP16_FP32;
};
@@ -218,6 +222,7 @@ struct scanline_layout: public distributed_layout {
// accessor
int mts(size_t k) { return mts_.at(k); }
int nts(size_t k) { return nts_.at(k); }
int contig_per_thread(size_t k) { return nts_.at(k); }
public:
// micro tile size. The size of a tile held by a thread block.

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@@ -208,10 +208,12 @@ mma_layout::mma_layout(size_t num_warps,
int pack_size_1 = (is_b_row && !is_b_vec4) ? 2 : 1;
rep_ = {2*pack_size_0, 2*pack_size_1, 1};
spw_ = {fpw_[0]*4*rep_[0], fpw_[1]*4*rep_[1], 1};
contig_per_thread_ = {1, 1};
}
else{
// fpw_ = {1, 1, 1};
spw_ = mma_instr_shape_.at(tensor_core_type_); // e.g., {16, 8, 16} for f32.f16.f16.f32
contig_per_thread_ = {1, 1};
// rep_ = {2, 2, 1};
}
order_ = {0, 1};
@@ -628,6 +630,12 @@ void layouts::run(ir::module &mod) {
shape[k] = std::max(in_layout->shape_per_cta(k),
out_layout->shape_per_cta(k));
}
auto in_ord = in_layout->get_order();
auto out_ord = out_layout->get_order();
int in_vec = in_layout->contig_per_thread(in_ord[0]);
int out_vec = out_layout->contig_per_thread(out_ord[0]);
int pad = std::max(in_vec, out_vec);
shape[out_ord[0]] += pad;
layouts_[id] = new shared_layout(out_layout, axes_->get(val), shape, {val}, val->get_type()->get_scalar_ty(), align_, tgt_);
tmp_[val] = id;
}

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@@ -14,41 +14,42 @@ void swizzle::run(ir::module &) {
max_phase_.clear();
for(auto &x: layouts_->get_all()){
shared_layout* layout = dynamic_cast<shared_layout*>(x.second);
if(!layout)
shared_layout* out_layout = dynamic_cast<shared_layout*>(x.second);
if(!out_layout)
continue;
ir::value* mma_dot_a = layout->hmma_dot_a();
ir::value* mma_dot_b = layout->hmma_dot_b();
if(!mma_dot_a && !mma_dot_b){
per_phase_[layout] = 1;
max_phase_[layout] = 1;
vec_[layout] = 1;
continue;
}
auto ord = layout->get_order();
scanline_layout* in_layout = dynamic_cast<scanline_layout*>(layout->get_arg_layout());
scanline_layout* in_layout = dynamic_cast<scanline_layout*>(out_layout->get_arg_layout());
if(!in_layout)
continue;
int dtsize = layout->get_type()->get_scalar_ty()->get_primitive_size_in_bits() / 8;
ir::value* mma_dot_a = out_layout->hmma_dot_a();
ir::value* mma_dot_b = out_layout->hmma_dot_b();
if(!mma_dot_a && !mma_dot_b){
per_phase_[out_layout] = 1;
max_phase_[out_layout] = 1;
vec_[out_layout] = 1;
continue;
}
auto ord = out_layout->get_order();
int dtsize = out_layout->get_type()->get_scalar_ty()->get_primitive_size_in_bits() / 8;
if(tgt_->as_nvidia() && tgt_->as_nvidia()->sm() < 80){
int inner = mma_dot_a ? 0 : 1;
per_phase_[layout] = std::max<int>(128 / (in_layout->mts(ord[0])*in_layout->nts(ord[0])*dtsize), 1);
max_phase_[layout] = (ord[inner] == 1 ? 8 : 4) / per_phase_[layout];
per_phase_[out_layout] = std::max<int>(128 / (in_layout->mts(ord[0])*in_layout->nts(ord[0])*dtsize), 1);
max_phase_[out_layout] = (ord[inner] == 1 ? 8 : 4) / per_phase_[out_layout];
if(mma_dot_a)
vec_[layout] = 2*layouts_->get(mma_dot_a)->to_mma()->rep(0);
vec_[out_layout] = 2*layouts_->get(mma_dot_a)->to_mma()->rep(0);
else
vec_[layout] = 2*layouts_->get(mma_dot_b)->to_mma()->rep(1);
vec_[out_layout] = 2*layouts_->get(mma_dot_b)->to_mma()->rep(1);
}
else {
if (!layout->allow_swizzle()) {
per_phase_[layout] = 1;
max_phase_[layout] = 1;
vec_[layout] = 1;
if (!out_layout->allow_swizzle()) {
per_phase_[out_layout] = 1;
max_phase_[out_layout] = 1;
vec_[out_layout] = 1;
} else {
per_phase_[layout] = std::max<int>(128 / (in_layout->mts(ord[0])*in_layout->nts(ord[0])*dtsize), 1);
max_phase_[layout] = layout->get_mma_strided() / per_phase_[layout];
vec_[layout] = layout->get_mma_vec();
per_phase_[out_layout] = std::max<int>(128 / (in_layout->mts(ord[0])*in_layout->nts(ord[0])*dtsize), 1);
max_phase_[out_layout] = out_layout->get_mma_strided() / per_phase_[out_layout];
vec_[out_layout] = out_layout->get_mma_vec();
}
}
}

View File

@@ -2377,8 +2377,11 @@ void generator::visit_layout_convert(ir::value *out, ir::value *in){
}
in_ord = in_layout->to_mma() ? out_ord : in_ord;
out_ord = out_layout->to_mma() ? in_ord : out_ord;
Value *in_ld = i32(shape[in_ord[0]]);
Value *out_ld = i32(shape[out_ord[0]]);
int in_vec = out_ord[0] == 0 ? 1 : in_layout->contig_per_thread(in_ord[0]);
int out_vec = out_ord[0] == 0 ? 1 : out_layout->contig_per_thread(out_ord[0]);
int pad = std::max(in_vec, out_vec);
Value *in_ld = i32(shape[in_ord[0]] + pad);
Value *out_ld = i32(shape[out_ord[0]] + pad);
for(int i = 0; i < n_reps[0]; i++)
for(int j = 0; j < n_reps[1]; j++){
int max_ii, max_jj;
@@ -2386,29 +2389,39 @@ void generator::visit_layout_convert(ir::value *out, ir::value *in){
max_ii = in_ax[0].size()/n_reps[0];
max_jj = in_ax[1].size()/n_reps[1];
for(int ii = 0; ii < max_ii; ii++)
for(int jj = 0; jj < max_jj; jj++){
for(int jj = 0; jj < max_jj; jj+=in_vec){
// shared mem pointer
indices_t offs = {in_ax[0][ii], in_ax[1][jj]};
Value *off = add(offs[out_ord[0]], mul(out_ld, offs[out_ord[1]]));
Value *ptr = gep(base, off);
// stash value to shared mem
indices_t idxs = {in_ax[0][i*max_ii + ii],
in_ax[1][j*max_jj + jj]};
store(bit_cast(vals_[in][idxs], ty), ptr);
Value* vals = UndefValue::get(vec_ty(ty, in_vec));
for(int jjj = 0; jjj < in_vec; jjj++){
indices_t idxs = {in_ax[0][i*max_ii + ii],
in_ax[1][j*max_jj + jj + jjj]};
Value* val = bit_cast(vals_[in][idxs], ty);
vals = insert_elt(vals, val, jjj);
}
ptr = bit_cast(ptr, ptr_ty(vals->getType(), ptr->getType()->getPointerAddressSpace()));
store(vals, ptr);
}
add_barrier();
max_ii = out_ax[0].size()/n_reps[0];
max_jj = out_ax[1].size()/n_reps[1];
for(int ii = 0; ii < max_ii; ii++)
for(int jj = 0; jj < max_jj; jj++){
for(int jj = 0; jj < max_jj; jj+=out_vec){
// shared mem pointer
indices_t offs = {out_ax[0][ii], out_ax[1][jj]};
Value *off = add(offs[out_ord[0]], mul(out_ld, offs[out_ord[1]]));
Value *ptr = gep(base, off);
ptr = bit_cast(ptr, ptr_ty(vec_ty(ty, out_vec), ptr->getType()->getPointerAddressSpace()));
// load value from shared rem
indices_t idxs = {out_ax[0][i*max_ii + ii],
out_ax[1][j*max_jj + jj]};
vals_[out][idxs] = load(ptr);
Value* vals = load(ptr);
for(int jjj = 0; jjj < out_vec; jjj++){
indices_t idxs = {out_ax[0][i*max_ii + ii],
out_ax[1][j*max_jj + jj + jjj]};
vals_[out][idxs] = extract_elt(vals, jjj);
}
}
}