[nvptx] Handle large vector reductions

Add support for vector reductions with openacc vector_length larger than
warp-size.

2019-01-07  Tom de Vries  <tdevries@suse.de>

	* config/nvptx/nvptx-protos.h (nvptx_output_red_partition): Declare.
	* config/nvptx/nvptx.c (vector_red_size, vector_red_align,
	vector_red_partition, vector_red_sym): New global variables.
	(nvptx_option_override): Initialize vector_red_sym.
	(nvptx_declare_function_name): Restore red_partition register.
	(nvptx_file_end): Emit code to declare the vector reduction variables.
	(nvptx_output_red_partition): New function.
	(nvptx_expand_shared_addr): Add vector argument. Use it to handle
	large vector reductions.
	(enum nvptx_builtins): Add NVPTX_BUILTIN_VECTOR_ADDR.
	(nvptx_init_builtins): Add VECTOR_ADDR.
	(nvptx_expand_builtin): Update call to nvptx_expand_shared_addr.
	Handle nvptx_expand_shared_addr.
	(nvptx_get_shared_red_addr): Add vector argument and handle large
	vectors.
	(nvptx_goacc_reduction_setup): Add offload_attrs argument and handle
	large vectors.
	(nvptx_goacc_reduction_init): Likewise.
	(nvptx_goacc_reduction_fini): Likewise.
	(nvptx_goacc_reduction_teardown): Likewise.
	(nvptx_goacc_reduction): Update calls to nvptx_goacc_reduction_{setup,
	init,fini,teardown}.
	(nvptx_init_axis_predicate): Initialize vector_red_partition.
	(nvptx_set_current_function): Init vector_red_partition.
	* config/nvptx/nvptx.md (UNSPECV_RED_PART): New unspecv.
	(nvptx_red_partition): New insn.
	* config/nvptx/nvptx.h (struct machine_function): Add red_partition.

From-SVN: r267631

gcc/ChangeLog

 2019-01-07  Tom de Vries  <tdevries@suse.de>
 
+	* config/nvptx/nvptx-protos.h (nvptx_output_red_partition): Declare.
+	* config/nvptx/nvptx.c (vector_red_size, vector_red_align,
+	vector_red_partition, vector_red_sym): New global variables.
+	(nvptx_option_override): Initialize vector_red_sym.
+	(nvptx_declare_function_name): Restore red_partition register.
+	(nvptx_file_end): Emit code to declare the vector reduction variables.
+	(nvptx_output_red_partition): New function.
+	(nvptx_expand_shared_addr): Add vector argument. Use it to handle
+	large vector reductions.
+	(enum nvptx_builtins): Add NVPTX_BUILTIN_VECTOR_ADDR.
+	(nvptx_init_builtins): Add VECTOR_ADDR.
+	(nvptx_expand_builtin): Update call to nvptx_expand_shared_addr.
+	Handle nvptx_expand_shared_addr.
+	(nvptx_get_shared_red_addr): Add vector argument and handle large
+	vectors.
+	(nvptx_goacc_reduction_setup): Add offload_attrs argument and handle
+	large vectors.
+	(nvptx_goacc_reduction_init): Likewise.
+	(nvptx_goacc_reduction_fini): Likewise.
+	(nvptx_goacc_reduction_teardown): Likewise.
+	(nvptx_goacc_reduction): Update calls to nvptx_goacc_reduction_{setup,
+	init,fini,teardown}.
+	(nvptx_init_axis_predicate): Initialize vector_red_partition.
+	(nvptx_set_current_function): Init vector_red_partition.
+	* config/nvptx/nvptx.md (UNSPECV_RED_PART): New unspecv.
+	(nvptx_red_partition): New insn.
+	* config/nvptx/nvptx.h (struct machine_function): Add red_partition.
+
+2019-01-07  Tom de Vries  <tdevries@suse.de>
+
 	PR target/85381
 	* config/nvptx/nvptx.c (nvptx_process_pars): Don't emit barriers for
 	empty loops.

gcc/config/nvptx/nvptx-protos.h

@@ -56,5 +56,6 @@ extern const char *nvptx_output_return (void);
 extern const char *nvptx_output_set_softstack (unsigned);
 extern const char *nvptx_output_simt_enter (rtx, rtx, rtx);
 extern const char *nvptx_output_simt_exit (rtx);
+extern const char *nvptx_output_red_partition (rtx, rtx);
 #endif
 #endif

gcc/config/nvptx/nvptx.h

@@ -224,6 +224,8 @@ struct GTY(()) machine_function
   rtx bcast_partition; /* Register containing the size of each
 			  vector's partition of share-memory used to
 			  broadcast state.  */
+  rtx red_partition; /* Similar to bcast_partition, except for vector
+			reductions.  */
   rtx sync_bar; /* Synchronization barrier ID for vectors.  */
   rtx unisimt_master; /* 'Master lane index' for -muniform-simt.  */
   rtx unisimt_predicate; /* Predicate for -muniform-simt.  */

gcc/config/nvptx/nvptx.md

@@ -68,6 +68,8 @@
 
    UNSPECV_SIMT_ENTER
    UNSPECV_SIMT_EXIT
+
+   UNSPECV_RED_PART
 ])
 
 (define_attr "subregs_ok" "false,true"
@@ -1508,3 +1510,13 @@
   ""
   "\\t.pragma \\\"nounroll\\\";"
   [(set_attr "predicable" "false")])
+
+(define_insn "nvptx_red_partition"
+  [(set (match_operand:DI 0 "nonimmediate_operand" "=R")
+	(unspec_volatile [(match_operand:DI 1 "const_int_operand")]
+	 UNSPECV_RED_PART))]
+  ""
+  {
+    return nvptx_output_red_partition (operands[0], operands[1]);
+  }
+  [(set_attr "predicable" "false")])