Richard,
this patch adds folding for the new GOACC_DIM_POS and GOACC_DIM_SIZE internal
functions. IIUC gimple_fold_call is the right place to add this.
The size of a compute dimension is very often a compile-time constant. On the
host, in particular it's 1, which means we can deduce the POS must be zero.
ok?
nathan
2015-10-28 Nathan Sidwell <nat...@codesourcery.com>
* gimple-fold.c: Include omp-low.h.
(fold_internal_goacc_dim): New.
(gimple_fold_call): Call it.
Index: gcc/gimple-fold.c
===================================================================
--- gcc/gimple-fold.c (revision 229488)
+++ gcc/gimple-fold.c (working copy)
@@ -64,6 +64,7 @@ along with GCC; see the file COPYING3.
#include "gimple-match.h"
#include "gomp-constants.h"
#include "optabs-query.h"
+#include "omp-low.h"
/* Return true when DECL can be referenced from current unit.
@@ -2925,6 +2926,40 @@ gimple_fold_builtin (gimple_stmt_iterato
return false;
}
+/* Transform IFN_GOACC_DIM_SIZE and IFN_GOACC_DIM_POS internal
+ function calls to constants, where possible. */
+
+static tree
+fold_internal_goacc_dim (gimple *call)
+{
+ tree size = integer_one_node;
+
+ if (tree attrs = get_oacc_fn_attrib (current_function_decl))
+ {
+ tree arg = gimple_call_arg (call, 0);
+ tree pos = TREE_VALUE (attrs);
+
+ for (unsigned axis = (unsigned) TREE_INT_CST_LOW (arg); axis--;)
+ pos = TREE_CHAIN (pos);
+ size = TREE_VALUE (pos);
+ }
+
+ tree result;
+ if (integer_zerop (size))
+ /* Dimension size is dynamic. */
+ result = NULL_TREE;
+ else if (gimple_call_internal_fn (call) == IFN_GOACC_DIM_SIZE)
+ result = size;
+ else if (integer_onep (size))
+ /* Size is one, so pos must be zero. */
+ result = integer_zero_node;
+ else
+ /* Size is more than 1, so POS might be non-zero. */
+ result = NULL_TREE;
+
+ return result;
+}
+
/* Return true if ARG0 CODE ARG1 in infinite signed precision operation
doesn't fit into TYPE. The test for overflow should be regardless of
-fwrapv, and even for unsigned types. */
@@ -3125,6 +3160,10 @@ gimple_fold_call (gimple_stmt_iterator *
return true;
}
break;
+ case IFN_GOACC_DIM_SIZE:
+ case IFN_GOACC_DIM_POS:
+ result = fold_internal_goacc_dim (stmt);
+ break;
case IFN_UBSAN_CHECK_ADD:
subcode = PLUS_EXPR;
break;
