[autovect] generic extract_even/odd

[Richard Henderson <rth at redhat dot com>]

Some common code that I expect will be used by several targets.
If a target has both interleave_high and interleave_low, then
sorting elements into even and odd sets can be done with three
operations.


r~


        * targhooks.c (interleave_vectorize_builtin_extract_evenodd): New.
        (interleave_vectorize_builtin_extract_even): New.
        (interleave_vectorize_builtin_extract_odd): New.
        * targhooks.h: Declare them.
        * config/i386/i386.c (TARGET_VECTORIZE_BUILTIN_EXTRACT_EVEN): New.
        (TARGET_VECTORIZE_BUILTIN_EXTRACT_ODD): New.

=== gcc/config/i386/i386.c
==================================================================
--- gcc/config/i386/i386.c	(revision 107839)
+++ gcc/config/i386/i386.c	(local)
@@ -1087,6 +1087,12 @@
 
 #undef TARGET_VECTOR_MODE_SUPPORTED_P
 #define TARGET_VECTOR_MODE_SUPPORTED_P ix86_vector_mode_supported_p
+#undef TARGET_VECTORIZE_BUILTIN_EXTRACT_EVEN
+#define TARGET_VECTORIZE_BUILTIN_EXTRACT_EVEN \
+  interleave_vectorize_builtin_extract_even
+#undef TARGET_VECTORIZE_BUILTIN_EXTRACT_ODD
+#define TARGET_VECTORIZE_BUILTIN_EXTRACT_ODD \
+  interleave_vectorize_builtin_extract_odd
 
 #ifdef HAVE_AS_TLS
 #undef TARGET_ASM_OUTPUT_DWARF_DTPREL
=== gcc/targhooks.c
==================================================================
--- gcc/targhooks.c	(revision 107839)
+++ gcc/targhooks.c	(local)
@@ -58,6 +58,8 @@
 #include "output.h"
 #include "toplev.h"
 #include "function.h"
+#include "tree-flow.h"
+#include "optabs.h"
 #include "target.h"
 #include "tm_p.h"
 #include "target-def.h"
@@ -439,4 +441,65 @@
 #endif
 }
 
+static tree
+interleave_vectorize_builtin_extract_evenodd (tree dest, tree vec1,
+					      tree vec2, tree stmt, bool odd_p)
+{
+  tree type;
+  enum machine_mode mode;
+  block_stmt_iterator bsi;
+  tree th, tl, result, x;
+
+  type = TREE_TYPE (dest);
+  mode = TYPE_MODE (type);
+
+  /* We require both high and low interleaves for the mode.  */
+  if (vec_interleave_high_optab->handlers[mode].insn_code == CODE_FOR_nothing
+      || vec_interleave_low_optab->handlers[mode].insn_code == CODE_FOR_nothing)
+    return NULL;
+
+  bsi = bsi_for_stmt (stmt);
+  
+  th = make_rename_temp (type, NULL);
+  x = build2 (VEC_INTERLEAVE_HIGH_EXPR, type, vec1, vec2);
+  x = build2 (MODIFY_EXPR, type, th, x);
+  th = make_ssa_name (th, x);
+  TREE_OPERAND (x, 0) = th;
+  bsi_insert_before (&bsi, x, BSI_SAME_STMT);
+
+  tl = make_rename_temp (type, NULL);
+  x = build2 (VEC_INTERLEAVE_LOW_EXPR, type, vec1, vec2);
+  x = build2 (MODIFY_EXPR, type, tl, x);
+  tl = make_ssa_name (tl, x);
+  TREE_OPERAND (x, 0) = tl;
+  bsi_insert_before (&bsi, x, BSI_SAME_STMT);
+
+  result = make_rename_temp (type, NULL);
+  /* ??? Endianness issues?  */
+  x = build2 (odd_p ? VEC_INTERLEAVE_HIGH_EXPR : VEC_INTERLEAVE_LOW_EXPR,
+	      type, th, tl);
+  x = build2 (MODIFY_EXPR, type, result, x);
+  result = make_ssa_name (result, x);
+  TREE_OPERAND (x, 0) = result;
+  bsi_insert_before (&bsi, x, BSI_SAME_STMT);
+
+  return result;
+}
+
+tree
+interleave_vectorize_builtin_extract_even (tree dest, tree vec1,
+					tree vec2, tree stmt)
+{
+  return interleave_vectorize_builtin_extract_evenodd (dest, vec1, vec2,
+						       stmt, false);
+}
+
+tree
+interleave_vectorize_builtin_extract_odd (tree dest, tree vec1,
+				       tree vec2, tree stmt)
+{
+  return interleave_vectorize_builtin_extract_evenodd (dest, vec1, vec2,
+						       stmt, true);
+}
+
 #include "gt-targhooks.h"
=== gcc/targhooks.h
==================================================================
--- gcc/targhooks.h	(revision 107839)
+++ gcc/targhooks.h	(local)
@@ -69,3 +69,5 @@
 extern bool hook_bool_rtx_commutative_p (rtx, int);
 extern rtx default_function_value (tree, tree, bool);
 
+extern tree interleave_vectorize_builtin_extract_even (tree, tree, tree, tree);
+extern tree interleave_vectorize_builtin_extract_odd (tree, tree, tree, tree);