This reverts commit 31e53aef12f574a8534f8aea219b5466edb75b32.
Re-measuring the effect of this patch across a set of benchmarks
shows that it appears to have an overall slightly negative effect on
performance. Thus, we are reverting it.
---
gcc/ChangeLog.omp | 11 ++
gcc/config/nvptx/nvptx.c | 229 ----------------------------------
libgomp/ChangeLog.omp | 13 ++
libgomp/plugin/plugin-nvptx.c | 163 +++++++++++++++++++++---
4 files changed, 173 insertions(+), 243 deletions(-)
diff --git a/gcc/ChangeLog.omp b/gcc/ChangeLog.omp
index 88754626121..b97c1acaf49 100644
--- a/gcc/ChangeLog.omp
+++ b/gcc/ChangeLog.omp
@@ -1,3 +1,14 @@
+2021-10-12 Julian Brown <jul...@codesourcery.com>
+
+ Revert:
+
+ 2019-09-10 Chung-Lin Tang <clt...@codesourcery.com>
+
+ * config/nvptx/nvptx.c (nvptx_expand_to_rtl_hook): New function
+ implementing CUDA .params space transformation.
+ (TARGET_EXPAND_TO_RTL_HOOK): implement hook with
+ nvptx_expand_to_rtl_hook.
+
2021-10-12 Tobias Burnus <tob...@codesourcery.com>
Backported from master:
diff --git a/gcc/config/nvptx/nvptx.c b/gcc/config/nvptx/nvptx.c
index 143be974fe8..e23c3902306 100644
--- a/gcc/config/nvptx/nvptx.c
+++ b/gcc/config/nvptx/nvptx.c
@@ -68,10 +68,6 @@
#include "attribs.h"
#include "tree-vrp.h"
#include "tree-ssa-operands.h"
-#include "tree-pretty-print.h"
-#include "gimple-pretty-print.h"
-#include "tree-cfg.h"
-#include "gimple-ssa.h"
#include "tree-ssanames.h"
#include "gimplify.h"
#include "tree-phinodes.h"
@@ -6339,228 +6335,6 @@ nvptx_libc_has_function (enum function_class fn_class,
tree type)
return default_libc_has_function (fn_class, type);
}
-static void
-nvptx_expand_to_rtl_hook (void)
-{
- /* For utilizing CUDA .param kernel arguments, we detect and modify
- the gimple of offloaded child functions, here before RTL expansion,
- starting with standard OMP form:
- foo._omp_fn.0 (const struct .omp_data_t.8 & restrict .omp_data_i) { ... }
-
- and transform it into a style where the OMP data record fields are
- "exploded" into individual scalar arguments:
- foo._omp_fn.0 (int * a, int * b, int * c) { ... }
-
- Note that there are implicit assumptions of how OMP lowering (and/or other
- intervening passes) behaves contained in this transformation code;
- if those passes change in their output, this code may possibly need
- updating. */
-
- if (lookup_attribute ("omp target entrypoint",
- DECL_ATTRIBUTES (current_function_decl))
- /* The rather indirect manner in which OpenMP target functions are
- launched makes this transformation only valid for OpenACC currently.
- TODO: e.g. write_omp_entry(), nvptx_declare_function_name(), etc.
- needs changes for this to work with OpenMP. */
- && lookup_attribute ("oacc function",
- DECL_ATTRIBUTES (current_function_decl))
- && VOID_TYPE_P (TREE_TYPE (DECL_RESULT (current_function_decl))))
- {
- tree omp_data_arg = DECL_ARGUMENTS (current_function_decl);
- tree argtype = TREE_TYPE (omp_data_arg);
-
- /* Ensure this function is of the form of a single reference argument
- to the OMP data record, or a single void* argument (when no values
- passed) */
- if (! (DECL_CHAIN (omp_data_arg) == NULL_TREE
- && ((TREE_CODE (argtype) == REFERENCE_TYPE
- && TREE_CODE (TREE_TYPE (argtype)) == RECORD_TYPE)
- || (TREE_CODE (argtype) == POINTER_TYPE
- && TREE_TYPE (argtype) == void_type_node))))
- return;
-
- if (dump_file)
- {
- fprintf (dump_file, "Detected offloaded child function %s, "
- "starting parameter conversion\n",
- print_generic_expr_to_str (current_function_decl));
- fprintf (dump_file, "OMP data record argument: %s (tree type: %s)\n",
- print_generic_expr_to_str (omp_data_arg),
- print_generic_expr_to_str (argtype));
- fprintf (dump_file, "Data record fields:\n");
- }
-
- hash_map<tree,tree> fld_to_args;
- tree fld, rectype = TREE_TYPE (argtype);
- tree arglist = NULL_TREE, argtypelist = NULL_TREE;
-
- if (TREE_CODE (rectype) == RECORD_TYPE)
- {
- /* For each field in the OMP data record type, create a corresponding
- PARM_DECL, and map field -> parm using the fld_to_args hash_map.
- Also create the tree chains for creating function type and
- DECL_ARGUMENTS below. */
- for (fld = TYPE_FIELDS (rectype); fld; fld = DECL_CHAIN (fld))
- {
- tree narg = build_decl (DECL_SOURCE_LOCATION (fld), PARM_DECL,
- DECL_NAME (fld), TREE_TYPE (fld));
- DECL_ARTIFICIAL (narg) = 1;
- DECL_ARG_TYPE (narg) = TREE_TYPE (fld);
- DECL_CONTEXT (narg) = current_function_decl;
- TREE_USED (narg) = 1;
- TREE_READONLY (narg) = 1;
-
- if (dump_file)
- fprintf (dump_file, "\t%s, type: %s, offset: %s bytes + %s
bits\n",
- print_generic_expr_to_str (fld),
- print_generic_expr_to_str (TREE_TYPE (fld)),
- print_generic_expr_to_str (DECL_FIELD_OFFSET (fld)),
- print_generic_expr_to_str (DECL_FIELD_BIT_OFFSET
(fld)));
- fld_to_args.put (fld, narg);
-
- TREE_CHAIN (narg) = arglist;
- arglist = narg;
- argtypelist = tree_cons (NULL_TREE, TREE_TYPE (narg),
- argtypelist);
- }
- arglist = nreverse (arglist);
- argtypelist = nreverse (argtypelist);
- }
- /* This is needed to not be mistaken for a stdarg function. */
- argtypelist = chainon (argtypelist, void_list_node);
-
- if (dump_file)
- {
- fprintf (dump_file, "Function before OMP data arg replaced:\n");
- dump_function_to_file (current_function_decl, dump_file, dump_flags);
- }
-
- /* Actually modify the tree type and DECL_ARGUMENTS here. */
- TREE_TYPE (current_function_decl) = build_function_type (void_type_node,
- argtypelist);
- DECL_ARGUMENTS (current_function_decl) = arglist;
-
- /* Remove local decls which correspond to *.omp_data_i->FIELD entries, by
- scanning and skipping those entries, creating a new local_decls list.
- We assume a very specific MEM_REF tree expression shape. */
- tree decl;
- unsigned int i;
- vec<tree, va_gc> *new_local_decls = NULL;
- FOR_EACH_VEC_SAFE_ELT (cfun->local_decls, i, decl)
- {
- if (DECL_HAS_VALUE_EXPR_P (decl))
- {
- tree t = DECL_VALUE_EXPR (decl);
- if (TREE_CODE (t) == MEM_REF
- && TREE_CODE (TREE_OPERAND (t, 0)) == COMPONENT_REF
- && TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)) ==
MEM_REF
- && (TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (t, 0), 0), 0)
- == omp_data_arg))
- continue;
- }
- vec_safe_push (new_local_decls, decl);
- }
- vec_free (cfun->local_decls);
- cfun->local_decls = new_local_decls;
-
- /* Scan function body for assignments from .omp_data_i->FIELD, and using
- the above created fld_to_args hash map, convert them to reads of
- function arguments. */
- basic_block bb;
- gimple_stmt_iterator gsi;
- FOR_EACH_BB_FN (bb, cfun)
- for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
- {
- tree val, *val_ptr = NULL;
- gimple *stmt = gsi_stmt (gsi);
- if (is_gimple_assign (stmt)
- && gimple_assign_rhs_class (stmt) == GIMPLE_SINGLE_RHS)
- val_ptr = gimple_assign_rhs1_ptr (stmt);
- else if (is_gimple_debug (stmt) && gimple_debug_bind_p (stmt))
- val_ptr = gimple_debug_bind_get_value_ptr (stmt);
-
- if (val_ptr == NULL || (val = *val_ptr) == NULL_TREE)
- continue;
-
- tree new_val = NULL_TREE, fld = NULL_TREE;
-
- if (TREE_CODE (val) == COMPONENT_REF
- && TREE_CODE (TREE_OPERAND (val, 0)) == MEM_REF
- && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (val, 0), 0))
- == SSA_NAME)
- && (SSA_NAME_VAR (TREE_OPERAND (TREE_OPERAND (val, 0), 0))
- == omp_data_arg))
- {
- /* .omp_data->FIELD case. */
- fld = TREE_OPERAND (val, 1);
- new_val = *fld_to_args.get (fld);
- }
- else if (TREE_CODE (val) == MEM_REF
- && TREE_CODE (TREE_OPERAND (val, 0)) == SSA_NAME
- && SSA_NAME_VAR (TREE_OPERAND (val, 0)) == omp_data_arg)
- {
- /* This case may happen in the final tree level optimization
- output, due to SLP:
- vect.XX = MEM <vector(1) unsigned long> [(void
*).omp_data_i_5(D) + 8B]
-
- Therefore here we need a more elaborate search of the field
- list to reverse map to which field the offset is referring
- to. */
- unsigned HOST_WIDE_INT offset
- = tree_to_uhwi (TREE_OPERAND (val, 1));
-
- for (hash_map<tree, tree>::iterator i = fld_to_args.begin ();
- i != fld_to_args.end (); ++i)
- {
- tree cur_fld = (*i).first;
- tree cur_arg = (*i).second;
- gcc_assert (TREE_CODE (cur_arg) == PARM_DECL);
-
- unsigned HOST_WIDE_INT cur_offset =
- (tree_to_uhwi (DECL_FIELD_OFFSET (cur_fld))
- + (tree_to_uhwi (DECL_FIELD_BIT_OFFSET (cur_fld))
- / BITS_PER_UNIT));
-
- if (offset == cur_offset)
- {
- new_val = build1 (VIEW_CONVERT_EXPR, TREE_TYPE (val),
- cur_arg);
- break;
- }
- }
- }
-
- /* If we found the corresponding OMP data record field, replace the
- RHS with the new created PARM_DECL. */
- if (new_val != NULL_TREE)
- {
- if (dump_file)
- {
- fprintf (dump_file, "For gimple stmt: ");
- print_gimple_stmt (dump_file, stmt, 0);
- fprintf (dump_file, "\tReplacing OMP recv ref %s with %s\n",
- print_generic_expr_to_str (val),
- print_generic_expr_to_str (new_val));
- }
- /* Write in looked up ARG as new RHS value. */
- *val_ptr = new_val;
- }
- }
-
- /* Delete SSA_NAMEs of .omp_data_i by setting them to NULL_TREE. */
- tree name;
- FOR_EACH_SSA_NAME (i, name, cfun)
- if (SSA_NAME_VAR (name) == omp_data_arg)
- (*SSANAMES (cfun))[SSA_NAME_VERSION (name)] = NULL_TREE;
-
- if (dump_file)
- {
- fprintf (dump_file, "Function after OMP data arg replaced: ");
- dump_function_to_file (current_function_decl, dump_file, dump_flags);
- }
- }
-}
-
#undef TARGET_OPTION_OVERRIDE
#define TARGET_OPTION_OVERRIDE nvptx_option_override
@@ -6715,9 +6489,6 @@ nvptx_expand_to_rtl_hook (void)
#undef TARGET_LIBC_HAS_FUNCTION
#define TARGET_LIBC_HAS_FUNCTION nvptx_libc_has_function
-#undef TARGET_EXPAND_TO_RTL_HOOK
-#define TARGET_EXPAND_TO_RTL_HOOK nvptx_expand_to_rtl_hook
-
struct gcc_target targetm = TARGET_INITIALIZER;
#include "gt-nvptx.h"
diff --git a/libgomp/ChangeLog.omp b/libgomp/ChangeLog.omp
index b39fe5dd2a4..7e8e35bb5fa 100644
--- a/libgomp/ChangeLog.omp
+++ b/libgomp/ChangeLog.omp
@@ -1,3 +1,16 @@
+2021-10-12 Julian Brown <jul...@codesourcery.com>
+
+ Revert:
+
+ 2019-09-10 Chung-Lin Tang <clt...@codesourcery.com>
+
+ * plugin/plugin-nvptx.c (nvptx_exec): Adjust arguments, add
+ kernel argument setup code, adjust cuLaunchKernel calling code.
+ (GOMP_OFFLOAD_openacc_exec): Adjust nvptx_exec call, delete
+ profiling code.
+ (GOMP_OFFLOAD_openacc_async_exec): Likewise.
+ (cuda_free_argmem): Delete function.
+
2021-10-12 Tobias Burnus <tob...@codesourcery.com>
Backported from master:
diff --git a/libgomp/plugin/plugin-nvptx.c b/libgomp/plugin/plugin-nvptx.c
index a9680962f51..f1b0d8d4fbd 100644
--- a/libgomp/plugin/plugin-nvptx.c
+++ b/libgomp/plugin/plugin-nvptx.c
@@ -731,24 +731,16 @@ link_ptx (CUmodule *module, const struct targ_ptx_obj
*ptx_objs,
static void
nvptx_exec (void (*fn), size_t mapnum, void **hostaddrs, void **devaddrs,
- unsigned *dims, CUstream stream)
+ unsigned *dims, void *targ_mem_desc,
+ CUdeviceptr dp, CUstream stream)
{
struct targ_fn_descriptor *targ_fn = (struct targ_fn_descriptor *) fn;
CUfunction function;
int i;
+ void *kargs[1];
struct nvptx_thread *nvthd = nvptx_thread ();
int warp_size = nvthd->ptx_dev->warp_size;
- void **kernel_args = NULL;
- GOMP_PLUGIN_debug (0, "prepare mappings (mapnum: %u)\n", (unsigned) mapnum);
-
- if (mapnum > 0)
- {
- kernel_args = alloca (mapnum * sizeof (void *));
- for (int i = 0; i < mapnum; i++)
- kernel_args[i] = (devaddrs[i] ? &devaddrs[i] : &hostaddrs[i]);
- }
-
function = targ_fn->fn;
/* Initialize the launch dimensions. Typically this is constant,
@@ -980,10 +972,11 @@ nvptx_exec (void (*fn), size_t mapnum, void **hostaddrs,
void **devaddrs,
api_info);
}
+ kargs[0] = &dp;
CUDA_CALL_ASSERT (cuLaunchKernel, function,
dims[GOMP_DIM_GANG], 1, 1,
dims[GOMP_DIM_VECTOR], dims[GOMP_DIM_WORKER], 1,
- 0, stream, kernel_args, 0);
+ 0, stream, kargs, 0);
if (profiling_p)
{
@@ -1463,7 +1456,66 @@ GOMP_OFFLOAD_openacc_exec (void (*fn) (void *), size_t
mapnum,
void **hostaddrs, void **devaddrs,
unsigned *dims, void *targ_mem_desc)
{
- nvptx_exec (fn, mapnum, hostaddrs, devaddrs, dims, NULL);
+ GOMP_PLUGIN_debug (0, " %s: prepare mappings\n", __FUNCTION__);
+
+ struct goacc_thread *thr = GOMP_PLUGIN_goacc_thread ();
+ acc_prof_info *prof_info = thr->prof_info;
+ acc_event_info data_event_info;
+ acc_api_info *api_info = thr->api_info;
+ bool profiling_p = __builtin_expect (prof_info != NULL, false);
+
+ void **hp = NULL;
+ CUdeviceptr dp = 0;
+
+ if (mapnum > 0)
+ {
+ size_t s = mapnum * sizeof (void *);
+ hp = alloca (s);
+ for (int i = 0; i < mapnum; i++)
+ hp[i] = (devaddrs[i] ? devaddrs[i] : hostaddrs[i]);
+ CUDA_CALL_ASSERT (cuMemAlloc, &dp, s);
+ if (profiling_p)
+ goacc_profiling_acc_ev_alloc (thr, (void *) dp, s);
+ }
+
+ /* Copy the (device) pointers to arguments to the device (dp and hp might in
+ fact have the same value on a unified-memory system). */
+ if (mapnum > 0)
+ {
+ if (profiling_p)
+ {
+ prof_info->event_type = acc_ev_enqueue_upload_start;
+
+ data_event_info.data_event.event_type = prof_info->event_type;
+ data_event_info.data_event.valid_bytes
+ = _ACC_DATA_EVENT_INFO_VALID_BYTES;
+ data_event_info.data_event.parent_construct
+ = acc_construct_parallel;
+ data_event_info.data_event.implicit = 1; /* Always implicit. */
+ data_event_info.data_event.tool_info = NULL;
+ data_event_info.data_event.var_name = NULL;
+ data_event_info.data_event.bytes = mapnum * sizeof (void *);
+ data_event_info.data_event.host_ptr = hp;
+ data_event_info.data_event.device_ptr = (const void *) dp;
+
+ api_info->device_api = acc_device_api_cuda;
+
+ GOMP_PLUGIN_goacc_profiling_dispatch (prof_info, &data_event_info,
+ api_info);
+ }
+ CUDA_CALL_ASSERT (cuMemcpyHtoD, dp, (void *) hp,
+ mapnum * sizeof (void *));
+ if (profiling_p)
+ {
+ prof_info->event_type = acc_ev_enqueue_upload_end;
+ data_event_info.data_event.event_type = prof_info->event_type;
+ GOMP_PLUGIN_goacc_profiling_dispatch (prof_info, &data_event_info,
+ api_info);
+ }
+ }
+
+ nvptx_exec (fn, mapnum, hostaddrs, devaddrs, dims, targ_mem_desc,
+ dp, NULL);
CUresult r = CUDA_CALL_NOCHECK (cuStreamSynchronize, NULL);
const char *maybe_abort_msg = "(perhaps abort was called)";
@@ -1472,6 +1524,18 @@ GOMP_OFFLOAD_openacc_exec (void (*fn) (void *), size_t
mapnum,
maybe_abort_msg);
else if (r != CUDA_SUCCESS)
GOMP_PLUGIN_fatal ("cuStreamSynchronize error: %s", cuda_error (r));
+
+ CUDA_CALL_ASSERT (cuMemFree, dp);
+ if (profiling_p)
+ goacc_profiling_acc_ev_free (thr, (void *) dp);
+}
+
+static void
+cuda_free_argmem (void *ptr)
+{
+ void **block = (void **) ptr;
+ nvptx_free (block[0], (struct ptx_device *) block[1]);
+ free (block);
}
void
@@ -1480,7 +1544,78 @@ GOMP_OFFLOAD_openacc_async_exec (void (*fn) (void *),
size_t mapnum,
unsigned *dims, void *targ_mem_desc,
struct goacc_asyncqueue *aq)
{
- nvptx_exec (fn, mapnum, hostaddrs, devaddrs, dims, aq->cuda_stream);
+ GOMP_PLUGIN_debug (0, " %s: prepare mappings\n", __FUNCTION__);
+
+ struct goacc_thread *thr = GOMP_PLUGIN_goacc_thread ();
+ acc_prof_info *prof_info = thr->prof_info;
+ acc_event_info data_event_info;
+ acc_api_info *api_info = thr->api_info;
+ bool profiling_p = __builtin_expect (prof_info != NULL, false);
+
+ void **hp = NULL;
+ CUdeviceptr dp = 0;
+ void **block = NULL;
+
+ if (mapnum > 0)
+ {
+ size_t s = mapnum * sizeof (void *);
+ block = (void **) GOMP_PLUGIN_malloc (2 * sizeof (void *) + s);
+ hp = block + 2;
+ for (int i = 0; i < mapnum; i++)
+ hp[i] = (devaddrs[i] ? devaddrs[i] : hostaddrs[i]);
+ CUDA_CALL_ASSERT (cuMemAlloc, &dp, s);
+ if (profiling_p)
+ goacc_profiling_acc_ev_alloc (thr, (void *) dp, s);
+ }
+
+ /* Copy the (device) pointers to arguments to the device (dp and hp might in
+ fact have the same value on a unified-memory system). */
+ if (mapnum > 0)
+ {
+ if (profiling_p)
+ {
+ prof_info->event_type = acc_ev_enqueue_upload_start;
+
+ data_event_info.data_event.event_type = prof_info->event_type;
+ data_event_info.data_event.valid_bytes
+ = _ACC_DATA_EVENT_INFO_VALID_BYTES;
+ data_event_info.data_event.parent_construct
+ = acc_construct_parallel;
+ data_event_info.data_event.implicit = 1; /* Always implicit. */
+ data_event_info.data_event.tool_info = NULL;
+ data_event_info.data_event.var_name = NULL;
+ data_event_info.data_event.bytes = mapnum * sizeof (void *);
+ data_event_info.data_event.host_ptr = hp;
+ data_event_info.data_event.device_ptr = (const void *) dp;
+
+ api_info->device_api = acc_device_api_cuda;
+
+ GOMP_PLUGIN_goacc_profiling_dispatch (prof_info, &data_event_info,
+ api_info);
+ }
+
+ CUDA_CALL_ASSERT (cuMemcpyHtoDAsync, dp, (void *) hp,
+ mapnum * sizeof (void *), aq->cuda_stream);
+ block[0] = (void *) dp;
+
+ struct nvptx_thread *nvthd =
+ (struct nvptx_thread *) GOMP_PLUGIN_acc_thread ();
+ block[1] = (void *) nvthd->ptx_dev;
+
+ if (profiling_p)
+ {
+ prof_info->event_type = acc_ev_enqueue_upload_end;
+ data_event_info.data_event.event_type = prof_info->event_type;
+ GOMP_PLUGIN_goacc_profiling_dispatch (prof_info, &data_event_info,
+ api_info);
+ }
+ }
+
+ nvptx_exec (fn, mapnum, hostaddrs, devaddrs, dims, targ_mem_desc,
+ dp, aq->cuda_stream);
+
+ if (mapnum > 0)
+ GOMP_OFFLOAD_openacc_async_queue_callback (aq, cuda_free_argmem, block);
}
void *
--
2.29.2
