re PR middle-end/59743 (ICE: Segmentation fault)

	PR middle-end/59743
	* ree.c (combine_reaching_defs): Ensure the defining statement
	occurs before the extension when optimizing extensions with
	different source and destination hard registers.

	PR middle-end/59743
	* gcc.c-torture/compile/pr59743.c: New test.

From-SVN: r206545

gcc/ChangeLog

+2014-01-10  Jeff Law  <law@redhat.com>
+
+	PR middle-end/59743
+	* ree.c (combine_reaching_defs): Ensure the defining statement
+	occurs before the extension when optimizing extensions with
+	different source and destination hard registers.
+
 2014-01-10  Jan Hubicka  <jh@suse.cz>
 
 	PR ipa/58585

gcc/ree.c

@@ -723,8 +723,10 @@ combine_reaching_defs (ext_cand *cand, const_rtx set_pat, ext_state *state)
 
       /* The defining statement and candidate insn must be in the same block.
 	 This is merely to keep the test for safety and updating the insn
-	 stream simple.  */
-      if (BLOCK_FOR_INSN (cand->insn) != BLOCK_FOR_INSN (def_insn))
+	 stream simple.  Also ensure that within the block the candidate
+	 follows the defining insn.  */
+      if (BLOCK_FOR_INSN (cand->insn) != BLOCK_FOR_INSN (def_insn)
+	  || DF_INSN_LUID (def_insn) > DF_INSN_LUID (cand->insn))
 	return false;
 
       /* If there is an overlap between the destination of DEF_INSN and

gcc/testsuite/ChangeLog

+2014-01-10  Jeff Law  <law@redhat.com>
+
+	PR middle-end/59743
+	* gcc.c-torture/compile/pr59743.c: New test.
+
 2014-01-10  Jan Hubicka  <jh@suse.cz>
 
 	PR ipa/58585

gcc/testsuite/gcc.c-torture/compile/pr59743.c

+/* PR middle-end/59743 */
+
+typedef union {
+  long all;
+  struct {
+    int low;
+    int high;
+  } s;
+} udwords;
+int a, b, c, d;
+void __udivmoddi4() {
+  udwords r;
+  d = __builtin_clz(0);
+  r.s.low = 0;
+  for (; d; --d) {
+    r.s.high = r.s.high << 1 | r.s.low >> a;
+    r.s.low = r.s.low << b >> 1;
+    int s = -r.all;
+    c = s;
+    r.all--;
+  }
+}
+