re PR rtl-optimization/89195 (Corrupted stack offset after combine)

	PR rtl-optimization/89195
	* combine.c (make_extraction): For MEMs, don't extract bytes outside
	of the original MEM.

	* gcc.c-torture/execute/pr89195.c: New test.

From-SVN: r268542

gcc/ChangeLog

+2019-02-05  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/89195
+	* combine.c (make_extraction): For MEMs, don't extract bytes outside
+	of the original MEM.
+
 2019-02-05  Martin Liska  <mliska@suse.cz>
 
 	PR gcov-profile/89000

gcc/combine.c

@@ -7687,6 +7687,7 @@ make_extraction (machine_mode mode, rtx inner, HOST_WIDE_INT pos,
 	      /* We can't do this if we are widening INNER_MODE (it
 		 may not be aligned, for one thing).  */
 	      && !paradoxical_subreg_p (tmode, inner_mode)
+	      && known_le (pos + len, GET_MODE_PRECISION (is_mode))
 	      && (inner_mode == tmode
 		  || (! mode_dependent_address_p (XEXP (inner, 0),
 						  MEM_ADDR_SPACE (inner))

gcc/testsuite/ChangeLog

+2019-02-05  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/89195
+	* gcc.c-torture/execute/pr89195.c: New test.
+
 2019-02-05  Kelvin Nilsen  <kelvin@gcc.gnu.org>
 
 	* gcc.target/powerpc/vec-extract-slong-1.c: Require p8 execution

gcc/testsuite/gcc.c-torture/execute/pr89195.c

+/* PR rtl-optimization/89195 */
+/* { dg-require-effective-target int32plus } */
+
+struct S { unsigned i : 24; };
+
+volatile unsigned char x;
+
+__attribute__((noipa)) int
+foo (struct S d) 
+{
+  return d.i & x;
+}
+
+int
+main ()
+{
+  struct S d = { 0x123456 };
+  x = 0x75;
+  if (foo (d) != (0x56 & 0x75))
+    __builtin_abort ();
+  return 0;
+}