sync LTO streaming and hashing for accelerators and vector type mode

The following syncs up LTO tree hashing and streaming of TYPE_MODE
and DECL_MODE which long had a discrepancy for vector types and
recently got special-casing of streaming for offloading.  Failure
to handle this results in less possible type merging to occur.
Note the compare step will still use TYPE_MODE and DECL_MODE.

	* lto-streamer-out.cc (hash_tree): Hash TYPE_MODE_RAW.
	When offloading hash modes as VOIDmode for aggregates
	and vectors.

diff --git a/gcc/lto-streamer-out.cc b/gcc/lto-streamer-out.cc
index a055d12d6bed0154e934ed1b3a853ab4d494c2cf..86d338461c0cb9a643cf67e3333b18d23fbf6dd0 100644 (file)
--- a/gcc/lto-streamer-out.cc
+++ b/gcc/lto-streamer-out.cc
@@ -1256,7 +1256,17 @@ hash_tree (struct streamer_tree_cache_d *cache, hash_map<tree, hashval_t> *map,
 
   if (CODE_CONTAINS_STRUCT (code, TS_DECL_COMMON))
     {
-      hstate.add_hwi (DECL_MODE (t));
+      /* Similar to TYPE_MODE, avoid streaming out host-specific DECL_MODE
+        for aggregate type with offloading enabled, and while streaming-in
+        recompute appropriate DECL_MODE for accelerator.  */
+      if (lto_stream_offload_p
+         && (VAR_P (t)
+             || TREE_CODE (t) == PARM_DECL
+             || TREE_CODE (t) == FIELD_DECL)
+         && AGGREGATE_TYPE_P (TREE_TYPE (t)))
+       hstate.add_hwi (VOIDmode);
+      else
+       hstate.add_hwi (DECL_MODE (t));
       hstate.add_flag (DECL_NONLOCAL (t));
       hstate.add_flag (DECL_VIRTUAL_P (t));
       hstate.add_flag (DECL_IGNORED_P (t));
@@ -1354,7 +1364,19 @@ hash_tree (struct streamer_tree_cache_d *cache, hash_map<tree, hashval_t> *map,
 
   if (CODE_CONTAINS_STRUCT (code, TS_TYPE_COMMON))
     {
-      hstate.add_hwi (TYPE_MODE (t));
+      /* For offloading, avoid streaming out TYPE_MODE for aggregate type since
+        it may be host-specific. For eg, aarch64 uses OImode for ARRAY_TYPE
+        whose size is 256-bits, which is not representable on accelerator.
+        Instead stream out VOIDmode, and while streaming-in, recompute
+        appropriate TYPE_MODE for accelerator.  */
+      if (lto_stream_offload_p
+         && (AGGREGATE_TYPE_P (t) || VECTOR_TYPE_P (t)))
+       hstate.add_hwi (VOIDmode);
+      /* for VECTOR_TYPE, TYPE_MODE reevaluates the mode using target_flags
+        not necessary valid in a global context.
+        Use the raw value previously set by layout_type.  */
+      else
+       hstate.add_hwi (TYPE_MODE_RAW (t));
       /* TYPE_NO_FORCE_BLK is private to stor-layout and need
         no streaming.  */
       hstate.add_flag (TYPE_PACKED (t));