[Aarch64] Fix alignment of neon loads & stores in gimple

[Andre Vieira (lists)]

Hi,

This fixes the alignment on the memory access type for neon loads & 
stores in the gimple lowering. Bootstrap ubsan on aarch64 builds again 
with this change.


2021-10-25  Andre Vieira  <andre.simoesdiasvieira@arm.com>

gcc/ChangeLog:

         * config/aarch64/aarch64-builtins.c 
(aarch64_general_gimple_fold_builtin): Fix memory access
         type alignment.


Is this OK for trunk?

Kind regards,
Andre
-------------- next part --------------
diff --git a/gcc/config/aarch64/aarch64-builtins.c b/gcc/config/aarch64/aarch64-builtins.c
index a815e4cfbccab692ca688ba87c71b06c304abbfb..f5436baf5f8a65c340e05faa491d86a7847c37d3 100644
--- a/gcc/config/aarch64/aarch64-builtins.c
+++ b/gcc/config/aarch64/aarch64-builtins.c
@@ -2490,12 +2490,16 @@ aarch64_general_gimple_fold_builtin (unsigned int fcode, gcall *stmt,
 	    gimple_seq stmts = NULL;
 	    tree base = gimple_convert (&stmts, elt_ptr_type,
 					args[0]);
+	    /* Use element type alignment.  */
+	    tree access_type
+	      = build_aligned_type (simd_type.itype,
+				    TYPE_ALIGN (TREE_TYPE (simd_type.itype)));
 	    if (stmts)
 	      gsi_insert_seq_before (gsi, stmts, GSI_SAME_STMT);
 	    new_stmt
 	      = gimple_build_assign (gimple_get_lhs (stmt),
 				     fold_build2 (MEM_REF,
-						  simd_type.itype,
+						  access_type,
 						  base, zero));
 	  }
 	break;
@@ -2512,13 +2516,16 @@ aarch64_general_gimple_fold_builtin (unsigned int fcode, gcall *stmt,
 	    gimple_seq stmts = NULL;
 	    tree base = gimple_convert (&stmts, elt_ptr_type,
 					args[0]);
+	    /* Use element type alignment.  */
+	    tree access_type
+	      = build_aligned_type (simd_type.itype,
+				    TYPE_ALIGN (TREE_TYPE (simd_type.itype)));
 	    if (stmts)
 	      gsi_insert_seq_before (gsi, stmts, GSI_SAME_STMT);
 	    new_stmt
-	      = gimple_build_assign (fold_build2 (MEM_REF,
-				     simd_type.itype,
-				     base,
-				     zero), args[1]);
+	      = gimple_build_assign (fold_build2 (MEM_REF, access_type,
+						  base, zero),
+				     args[1]);
 	  }
 	break;