nvptx.c (global_lock_var): New.

gcc/
	* config/nvptx/nvptx.c (global_lock_var): New.
	(nvptx_global_lock_addr): New.
	(nvptx_lockless_update): Recomment and adjust for clarity.
	(nvptx_lockfull_update): New.
	(nvptx_reduction_update): New.
	(nvptx_goacc_reduction_fini): Call it.

	libgcc/
	* config/nvptx/reduction.c: New.
	* config/nvptx/t-nvptx (LIB2ADD): Add it.

	libgomp/
	* testsuite/libgomp.oacc-c-c++-common/reduction-cplx-flt.c: Add
	worker & gang cases.
	* testsuite/libgomp.oacc-c-c++-common/reduction-cplx-dbl.c: Likewise.

From-SVN: r230545
This commit is contained in:
Nathan Sidwell 2015-11-18 13:49:17 +00:00 committed by Nathan Sidwell
parent d085c46817
commit 33f47f4279
8 changed files with 412 additions and 74 deletions

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@ -1,3 +1,12 @@
2015-11-18 Nathan Sidwell <nathan@codesourcery.com>
* config/nvptx/nvptx.c (global_lock_var): New.
(nvptx_global_lock_addr): New.
(nvptx_lockless_update): Recomment and adjust for clarity.
(nvptx_lockfull_update): New.
(nvptx_reduction_update): New.
(nvptx_goacc_reduction_fini): Call it.
2015-11-18 Bernd Schmidt <bschmidt@redhat.com>
* regrename.h (struct du_head): Add target_data_1 and target_data_2

View File

@ -114,6 +114,9 @@ static unsigned worker_red_align;
#define worker_red_name "__worker_red"
static GTY(()) rtx worker_red_sym;
/* Global lock variable, needed for 128bit worker & gang reductions. */
static GTY(()) tree global_lock_var;
/* Allocate a new, cleared machine_function structure. */
static struct machine_function *
@ -3681,8 +3684,45 @@ nvptx_generate_vector_shuffle (location_t loc,
gimplify_assign (dest_var, expr, seq);
}
/* Insert code to locklessly update *PTR with *PTR OP VAR just before
GSI. */
/* Lazily generate the global lock var decl and return its address. */
static tree
nvptx_global_lock_addr ()
{
tree v = global_lock_var;
if (!v)
{
tree name = get_identifier ("__reduction_lock");
tree type = build_qualified_type (unsigned_type_node,
TYPE_QUAL_VOLATILE);
v = build_decl (BUILTINS_LOCATION, VAR_DECL, name, type);
global_lock_var = v;
DECL_ARTIFICIAL (v) = 1;
DECL_EXTERNAL (v) = 1;
TREE_STATIC (v) = 1;
TREE_PUBLIC (v) = 1;
TREE_USED (v) = 1;
mark_addressable (v);
mark_decl_referenced (v);
}
return build_fold_addr_expr (v);
}
/* Insert code to locklessly update *PTR with *PTR OP VAR just before
GSI. We use a lockless scheme for nearly all case, which looks
like:
actual = initval(OP);
do {
guess = actual;
write = guess OP myval;
actual = cmp&swap (ptr, guess, write)
} while (actual bit-different-to guess);
return write;
This relies on a cmp&swap instruction, which is available for 32-
and 64-bit types. Larger types must use a locking scheme. */
static tree
nvptx_lockless_update (location_t loc, gimple_stmt_iterator *gsi,
@ -3690,46 +3730,30 @@ nvptx_lockless_update (location_t loc, gimple_stmt_iterator *gsi,
{
unsigned fn = NVPTX_BUILTIN_CMP_SWAP;
tree_code code = NOP_EXPR;
tree type = unsigned_type_node;
tree arg_type = unsigned_type_node;
tree var_type = TREE_TYPE (var);
enum machine_mode mode = TYPE_MODE (TREE_TYPE (var));
if (!INTEGRAL_MODE_P (mode))
if (TREE_CODE (var_type) == COMPLEX_TYPE
|| TREE_CODE (var_type) == REAL_TYPE)
code = VIEW_CONVERT_EXPR;
if (GET_MODE_SIZE (mode) == GET_MODE_SIZE (DImode))
if (TYPE_SIZE (var_type) == TYPE_SIZE (long_long_unsigned_type_node))
{
arg_type = long_long_unsigned_type_node;
fn = NVPTX_BUILTIN_CMP_SWAPLL;
type = long_long_unsigned_type_node;
}
tree swap_fn = nvptx_builtin_decl (fn, true);
gimple_seq init_seq = NULL;
tree init_var = make_ssa_name (type);
tree init_expr = omp_reduction_init_op (loc, op, TREE_TYPE (var));
init_expr = fold_build1 (code, type, init_expr);
tree init_var = make_ssa_name (arg_type);
tree init_expr = omp_reduction_init_op (loc, op, var_type);
init_expr = fold_build1 (code, arg_type, init_expr);
gimplify_assign (init_var, init_expr, &init_seq);
gimple *init_end = gimple_seq_last (init_seq);
gsi_insert_seq_before (gsi, init_seq, GSI_SAME_STMT);
gimple_seq loop_seq = NULL;
tree expect_var = make_ssa_name (type);
tree actual_var = make_ssa_name (type);
tree write_var = make_ssa_name (type);
tree write_expr = fold_build1 (code, TREE_TYPE (var), expect_var);
write_expr = fold_build2 (op, TREE_TYPE (var), write_expr, var);
write_expr = fold_build1 (code, type, write_expr);
gimplify_assign (write_var, write_expr, &loop_seq);
tree swap_expr = nvptx_builtin_decl (fn, true);
swap_expr = build_call_expr_loc (loc, swap_expr, 3,
ptr, expect_var, write_var);
gimplify_assign (actual_var, swap_expr, &loop_seq);
gcond *cond = gimple_build_cond (EQ_EXPR, actual_var, expect_var,
NULL_TREE, NULL_TREE);
gimple_seq_add_stmt (&loop_seq, cond);
/* Split the block just after the init stmts. */
basic_block pre_bb = gsi_bb (*gsi);
edge pre_edge = split_block (pre_bb, init_end);
@ -3738,12 +3762,34 @@ nvptx_lockless_update (location_t loc, gimple_stmt_iterator *gsi,
/* Reset the iterator. */
*gsi = gsi_for_stmt (gsi_stmt (*gsi));
/* Insert the loop statements. */
gimple *loop_end = gimple_seq_last (loop_seq);
gsi_insert_seq_before (gsi, loop_seq, GSI_SAME_STMT);
tree expect_var = make_ssa_name (arg_type);
tree actual_var = make_ssa_name (arg_type);
tree write_var = make_ssa_name (arg_type);
/* Build and insert the reduction calculation. */
gimple_seq red_seq = NULL;
tree write_expr = fold_build1 (code, var_type, expect_var);
write_expr = fold_build2 (op, var_type, write_expr, var);
write_expr = fold_build1 (code, arg_type, write_expr);
gimplify_assign (write_var, write_expr, &red_seq);
/* Split the block just after the loop stmts. */
edge post_edge = split_block (loop_bb, loop_end);
gsi_insert_seq_before (gsi, red_seq, GSI_SAME_STMT);
/* Build & insert the cmp&swap sequence. */
gimple_seq latch_seq = NULL;
tree swap_expr = build_call_expr_loc (loc, swap_fn, 3,
ptr, expect_var, write_var);
gimplify_assign (actual_var, swap_expr, &latch_seq);
gcond *cond = gimple_build_cond (EQ_EXPR, actual_var, expect_var,
NULL_TREE, NULL_TREE);
gimple_seq_add_stmt (&latch_seq, cond);
gimple *latch_end = gimple_seq_last (latch_seq);
gsi_insert_seq_before (gsi, latch_seq, GSI_SAME_STMT);
/* Split the block just after the latch stmts. */
edge post_edge = split_block (loop_bb, latch_end);
basic_block post_bb = post_edge->dest;
loop_bb = post_edge->src;
*gsi = gsi_for_stmt (gsi_stmt (*gsi));
@ -3762,7 +3808,123 @@ nvptx_lockless_update (location_t loc, gimple_stmt_iterator *gsi,
loop->latch = loop_bb;
add_loop (loop, loop_bb->loop_father);
return fold_build1 (code, TREE_TYPE (var), write_var);
return fold_build1 (code, var_type, write_var);
}
/* Insert code to lockfully update *PTR with *PTR OP VAR just before
GSI. This is necessary for types larger than 64 bits, where there
is no cmp&swap instruction to implement a lockless scheme. We use
a lock variable in global memory.
while (cmp&swap (&lock_var, 0, 1))
continue;
T accum = *ptr;
accum = accum OP var;
*ptr = accum;
cmp&swap (&lock_var, 1, 0);
return accum;
A lock in global memory is necessary to force execution engine
descheduling and avoid resource starvation that can occur if the
lock is in .shared memory. */
static tree
nvptx_lockfull_update (location_t loc, gimple_stmt_iterator *gsi,
tree ptr, tree var, tree_code op)
{
tree var_type = TREE_TYPE (var);
tree swap_fn = nvptx_builtin_decl (NVPTX_BUILTIN_CMP_SWAP, true);
tree uns_unlocked = build_int_cst (unsigned_type_node, 0);
tree uns_locked = build_int_cst (unsigned_type_node, 1);
/* Split the block just before the gsi. Insert a gimple nop to make
this easier. */
gimple *nop = gimple_build_nop ();
gsi_insert_before (gsi, nop, GSI_SAME_STMT);
basic_block entry_bb = gsi_bb (*gsi);
edge entry_edge = split_block (entry_bb, nop);
basic_block lock_bb = entry_edge->dest;
/* Reset the iterator. */
*gsi = gsi_for_stmt (gsi_stmt (*gsi));
/* Build and insert the locking sequence. */
gimple_seq lock_seq = NULL;
tree lock_var = make_ssa_name (unsigned_type_node);
tree lock_expr = nvptx_global_lock_addr ();
lock_expr = build_call_expr_loc (loc, swap_fn, 3, lock_expr,
uns_unlocked, uns_locked);
gimplify_assign (lock_var, lock_expr, &lock_seq);
gcond *cond = gimple_build_cond (EQ_EXPR, lock_var, uns_unlocked,
NULL_TREE, NULL_TREE);
gimple_seq_add_stmt (&lock_seq, cond);
gimple *lock_end = gimple_seq_last (lock_seq);
gsi_insert_seq_before (gsi, lock_seq, GSI_SAME_STMT);
/* Split the block just after the lock sequence. */
edge locked_edge = split_block (lock_bb, lock_end);
basic_block update_bb = locked_edge->dest;
lock_bb = locked_edge->src;
*gsi = gsi_for_stmt (gsi_stmt (*gsi));
/* Create the lock loop ... */
locked_edge->flags ^= EDGE_TRUE_VALUE | EDGE_FALLTHRU;
make_edge (lock_bb, lock_bb, EDGE_FALSE_VALUE);
set_immediate_dominator (CDI_DOMINATORS, lock_bb, entry_bb);
set_immediate_dominator (CDI_DOMINATORS, update_bb, lock_bb);
/* ... and the loop structure. */
loop *lock_loop = alloc_loop ();
lock_loop->header = lock_bb;
lock_loop->latch = lock_bb;
lock_loop->nb_iterations_estimate = 1;
lock_loop->any_estimate = true;
add_loop (lock_loop, entry_bb->loop_father);
/* Build and insert the reduction calculation. */
gimple_seq red_seq = NULL;
tree acc_in = make_ssa_name (var_type);
tree ref_in = build_simple_mem_ref (ptr);
TREE_THIS_VOLATILE (ref_in) = 1;
gimplify_assign (acc_in, ref_in, &red_seq);
tree acc_out = make_ssa_name (var_type);
tree update_expr = fold_build2 (op, var_type, ref_in, var);
gimplify_assign (acc_out, update_expr, &red_seq);
tree ref_out = build_simple_mem_ref (ptr);
TREE_THIS_VOLATILE (ref_out) = 1;
gimplify_assign (ref_out, acc_out, &red_seq);
gsi_insert_seq_before (gsi, red_seq, GSI_SAME_STMT);
/* Build & insert the unlock sequence. */
gimple_seq unlock_seq = NULL;
tree unlock_expr = nvptx_global_lock_addr ();
unlock_expr = build_call_expr_loc (loc, swap_fn, 3, unlock_expr,
uns_locked, uns_unlocked);
gimplify_and_add (unlock_expr, &unlock_seq);
gsi_insert_seq_before (gsi, unlock_seq, GSI_SAME_STMT);
return acc_out;
}
/* Emit a sequence to update a reduction accumlator at *PTR with the
value held in VAR using operator OP. Return the updated value.
TODO: optimize for atomic ops and indepedent complex ops. */
static tree
nvptx_reduction_update (location_t loc, gimple_stmt_iterator *gsi,
tree ptr, tree var, tree_code op)
{
tree type = TREE_TYPE (var);
tree size = TYPE_SIZE (type);
if (size == TYPE_SIZE (unsigned_type_node)
|| size == TYPE_SIZE (long_long_unsigned_type_node))
return nvptx_lockless_update (loc, gsi, ptr, var, op);
else
return nvptx_lockfull_update (loc, gsi, ptr, var, op);
}
/* NVPTX implementation of GOACC_REDUCTION_SETUP. */
@ -3944,11 +4106,11 @@ nvptx_goacc_reduction_fini (gcall *call)
if (accum)
{
/* Locklessly update the accumulator. */
/* UPDATE the accumulator. */
gsi_insert_seq_before (&gsi, seq, GSI_SAME_STMT);
seq = NULL;
r = nvptx_lockless_update (gimple_location (call), &gsi,
accum, var, op);
r = nvptx_reduction_update (gimple_location (call), &gsi,
accum, var, op);
}
}

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@ -1,3 +1,8 @@
2015-11-18 Nathan Sidwell <nathan@codesourcery.com>
* config/nvptx/reduction.c: New.
* config/nvptx/t-nvptx (LIB2ADD): Add it.
2015-11-15 David Edelsohn <dje.gcc@gmail.com>
* config/rs6000/on_exit.c: New file.

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@ -0,0 +1,31 @@
/* Oversized reductions lock variable
Copyright (C) 2015 Free Software Foundation, Inc.
Contributed by Mentor Graphics.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* We use a global lock variable for reductions on objects larger than
64 bits. Until and unless proven that lock contention for
different reduction is a problem, a single lock will suffice. */
unsigned volatile __reduction_lock = 0;

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@ -1,6 +1,7 @@
LIB2ADD=$(srcdir)/config/nvptx/malloc.asm \
$(srcdir)/config/nvptx/free.asm \
$(srcdir)/config/nvptx/realloc.c
$(srcdir)/config/nvptx/realloc.c \
$(srcdir)/config/nvptx/reduction.c
LIB2ADDEH=
LIB2FUNCS_EXCLUDE=__main

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@ -1,3 +1,9 @@
2015-11-18 Nathan Sidwell <nathan@codesourcery.com>
* testsuite/libgomp.oacc-c-c++-common/reduction-cplx-flt.c: Add
worker & gang cases.
* testsuite/libgomp.oacc-c-c++-common/reduction-cplx-dbl.c: Likewise.
2015-11-17 Cesar Philippidis <cesar@codesourcery.com>
* config/nvptx/priority_queue.c: New file.

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@ -14,28 +14,17 @@ int close_enough (double _Complex a, double _Complex b)
return mag2_diff / mag2_a < (FRAC * FRAC);
}
int main (void)
{
#define N 100
double _Complex ary[N], sum, prod, tsum, tprod;
int ix;
sum = tsum = 0;
prod = tprod = 1;
for (ix = 0; ix < N; ix++)
{
double frac = ix * (1.0 / 1024) + 1.0;
ary[ix] = frac + frac * 2.0i - 1.0i;
sum += ary[ix];
prod *= ary[ix];
}
static int __attribute__ ((noinline))
vector (double _Complex ary[N], double _Complex sum, double _Complex prod)
{
double _Complex tsum = 0, tprod = 1;
#pragma acc parallel vector_length(32) copyin(ary) copy (tsum, tprod)
#pragma acc parallel vector_length(32) copyin(ary[0:N]) copy (tsum, tprod)
{
#pragma acc loop vector reduction(+:tsum) reduction (*:tprod)
for (ix = 0; ix < N; ix++)
for (int ix = 0; ix < N; ix++)
{
tsum += ary[ix];
tprod *= ary[ix];
@ -50,3 +39,76 @@ int main (void)
return 0;
}
static int __attribute__ ((noinline))
worker (double _Complex ary[N], double _Complex sum, double _Complex prod)
{
double _Complex tsum = 0, tprod = 1;
#pragma acc parallel num_workers(32) copyin(ary[0:N]) copy (tsum, tprod)
{
#pragma acc loop worker reduction(+:tsum) reduction (*:tprod)
for (int ix = 0; ix < N; ix++)
{
tsum += ary[ix];
tprod *= ary[ix];
}
}
if (!close_enough (sum, tsum))
return 1;
if (!close_enough (prod, tprod))
return 1;
return 0;
}
static int __attribute__ ((noinline))
gang (double _Complex ary[N], double _Complex sum, double _Complex prod)
{
double _Complex tsum = 0, tprod = 1;
#pragma acc parallel num_gangs (32) copyin(ary[0:N]) copy (tsum, tprod)
{
#pragma acc loop gang reduction(+:tsum) reduction (*:tprod)
for (int ix = 0; ix < N; ix++)
{
tsum += ary[ix];
tprod *= ary[ix];
}
}
if (!close_enough (sum, tsum))
return 1;
if (!close_enough (prod, tprod))
return 1;
return 0;
}
int main (void)
{
double _Complex ary[N], sum = 0, prod = 1;
for (int ix = 0; ix < N; ix++)
{
double frac = ix * (1.0 / 1024) + 1.0;
ary[ix] = frac + frac * 2.0i - 1.0i;
sum += ary[ix];
prod *= ary[ix];
}
if (vector (ary, sum, prod))
return 1;
if (worker (ary, sum, prod))
return 1;
if (gang (ary, sum, prod))
return 1;
return 0;
}

View File

@ -14,28 +14,17 @@ int close_enough (float _Complex a, float _Complex b)
return mag2_diff / mag2_a < (FRAC * FRAC);
}
int main (void)
{
#define N 100
float _Complex ary[N], sum, prod, tsum, tprod;
int ix;
sum = tsum = 0;
prod = tprod = 1;
for (ix = 0; ix < N; ix++)
{
float frac = ix * (1.0f / 1024) + 1.0f;
ary[ix] = frac + frac * 2.0i - 1.0i;
sum += ary[ix];
prod *= ary[ix];
}
static int __attribute__ ((noinline))
vector (float _Complex ary[N], float _Complex sum, float _Complex prod)
{
float _Complex tsum = 0, tprod = 1;
#pragma acc parallel vector_length(32) copyin(ary) copy (tsum, tprod)
#pragma acc parallel vector_length(32) copyin(ary[0:N]) copy (tsum, tprod)
{
#pragma acc loop vector reduction(+:tsum) reduction (*:tprod)
for (ix = 0; ix < N; ix++)
for (int ix = 0; ix < N; ix++)
{
tsum += ary[ix];
tprod *= ary[ix];
@ -50,3 +39,76 @@ int main (void)
return 0;
}
static int __attribute__ ((noinline))
worker (float _Complex ary[N], float _Complex sum, float _Complex prod)
{
float _Complex tsum = 0, tprod = 1;
#pragma acc parallel num_workers(32) copyin(ary[0:N]) copy (tsum, tprod)
{
#pragma acc loop worker reduction(+:tsum) reduction (*:tprod)
for (int ix = 0; ix < N; ix++)
{
tsum += ary[ix];
tprod *= ary[ix];
}
}
if (!close_enough (sum, tsum))
return 1;
if (!close_enough (prod, tprod))
return 1;
return 0;
}
static int __attribute__ ((noinline))
gang (float _Complex ary[N], float _Complex sum, float _Complex prod)
{
float _Complex tsum = 0, tprod = 1;
#pragma acc parallel num_gangs (32) copyin(ary[0:N]) copy (tsum, tprod)
{
#pragma acc loop gang reduction(+:tsum) reduction (*:tprod)
for (int ix = 0; ix < N; ix++)
{
tsum += ary[ix];
tprod *= ary[ix];
}
}
if (!close_enough (sum, tsum))
return 1;
if (!close_enough (prod, tprod))
return 1;
return 0;
}
int main (void)
{
float _Complex ary[N], sum = 0, prod = 1;
for (int ix = 0; ix < N; ix++)
{
float frac = ix * (1.0f / 1024) + 1.0f;
ary[ix] = frac + frac * 2.0i - 1.0i;
sum += ary[ix];
prod *= ary[ix];
}
if (vector (ary, sum, prod))
return 1;
if (worker (ary, sum, prod))
return 1;
if (gang (ary, sum, prod))
return 1;
return 0;
}