re PR middle-end/80262 (address space gets lost in memory access)

2017-04-06  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/80262
	* tree-sra.c (build_ref_for_offset): Preserve address-space
	information.
	* tree-ssa-sccvn.c (vn_reference_maybe_forwprop_address):
	Drop useless address-space information on MEM_REF offsets.

	* gcc.target/i386/pr80262.c: New testcase.

From-SVN: r246728

gcc/ChangeLog

+2017-04-06  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/80262
+	* tree-sra.c (build_ref_for_offset): Preserve address-space
+	information.
+	* tree-ssa-sccvn.c (vn_reference_maybe_forwprop_address):
+	Drop useless address-space information on MEM_REF offsets.
+
 2017-04-05  Andreas Schwab  <schwab@linux-m68k.org>
 
 	* builtins.def (BUILT_IN_UPDATE_SETJMP_BUF): Fix type.

gcc/testsuite/ChangeLog

 2017-04-06  Richard Biener  <rguenther@suse.de>
 
+	PR tree-optimization/80262
+	* gcc.target/i386/pr80262.c: New testcase.
+
+2017-04-06  Richard Biener  <rguenther@suse.de>
+
 	PR middle-end/80281
 	* gcc.dg/tree-ssa/pr40921.c: Add -fp-contract=off.
 

gcc/testsuite/gcc.target/i386/pr80262.c

+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+typedef struct {
+  int v;
+} S1;
+S1 clearS1 () { S1 s1 = { 0 }; return s1; }
+ 
+typedef struct {
+  S1 s1[4];
+} S2;
+void clearS2 (__seg_gs S2* p, int n) {
+  for (int i = 0; i < n; ++i)
+    p->s1[i] = clearS1 ();
+}
+ 
+typedef struct {
+  int pad;
+  S2 s2;
+} S3;
+ 
+long int BASE;
+ 
+void fn1(int n) {
+  clearS2 (&(((__seg_gs S3*)(BASE))->s2), n);
+}

gcc/tree-sra.c

@@ -1638,6 +1638,13 @@ build_ref_for_offset (location_t loc, tree base, HOST_WIDE_INT offset,
   unsigned HOST_WIDE_INT misalign;
   unsigned int align;
 
+  /* Preserve address-space information.  */
+  addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (base));
+  if (as != TYPE_ADDR_SPACE (exp_type))
+    exp_type = build_qualified_type (exp_type,
+				     TYPE_QUALS (exp_type)
+				     | ENCODE_QUAL_ADDR_SPACE (as));
+
   gcc_checking_assert (offset % BITS_PER_UNIT == 0);
   get_object_alignment_1 (base, &align, &misalign);
   base = get_addr_base_and_unit_offset (base, &base_offset);

gcc/tree-ssa-sccvn.c

@@ -1233,8 +1233,8 @@ vn_reference_maybe_forwprop_address (vec<vn_reference_op_s> *ops,
 	      && tem[tem.length () - 2].opcode == MEM_REF)
 	    {
 	      vn_reference_op_t new_mem_op = &tem[tem.length () - 2];
-	      new_mem_op->op0 = fold_convert (TREE_TYPE (mem_op->op0),
-					      new_mem_op->op0);
+	      new_mem_op->op0 = wide_int_to_tree (TREE_TYPE (mem_op->op0),
+						  new_mem_op->op0);
 	    }
 	  else
 	    gcc_assert (tem.last ().opcode == STRING_CST);