re PR target/86314 (GCC 7.x and 8.x zero out "eax" before using "rax" in "lock bts")

	PR target/86314
	* config/i386/i386.md (setcc + movzbl to xor + setcc peephole2s):
	Check reg_overlap_mentioned_p in addition to reg_set_p with the same
	operands.

	* gcc.dg/pr86314.c: New test.

From-SVN: r262141

gcc/ChangeLog

+2018-06-26  Jakub Jelinek  <jakub@redhat.com>
+
+	PR target/86314
+	* config/i386/i386.md (setcc + movzbl to xor + setcc peephole2s):
+	Check reg_overlap_mentioned_p in addition to reg_set_p with the same
+	operands.
+
 2018-06-26  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/86287

gcc/config/i386/i386.md

@@ -12761,6 +12761,7 @@
   "(peep2_reg_dead_p (3, operands[1])
     || operands_match_p (operands[1], operands[3]))
    && ! reg_overlap_mentioned_p (operands[3], operands[0])
+   && ! reg_overlap_mentioned_p (operands[3], operands[4])
    && ! reg_set_p (operands[3], operands[4])
    && peep2_regno_dead_p (0, FLAGS_REG)"
   [(parallel [(set (match_dup 5) (match_dup 0))
@@ -12786,6 +12787,7 @@
     || operands_match_p (operands[2], operands[4]))
    && ! reg_overlap_mentioned_p (operands[4], operands[0])
    && ! reg_overlap_mentioned_p (operands[4], operands[1])
+   && ! reg_overlap_mentioned_p (operands[4], operands[5])
    && ! reg_set_p (operands[4], operands[5])
    && refers_to_regno_p (FLAGS_REG, operands[1], (rtx *)NULL)
    && peep2_regno_dead_p (0, FLAGS_REG)"
@@ -12835,6 +12837,7 @@
   "(peep2_reg_dead_p (3, operands[1])
     || operands_match_p (operands[1], operands[3]))
    && ! reg_overlap_mentioned_p (operands[3], operands[0])
+   && ! reg_overlap_mentioned_p (operands[3], operands[4])
    && ! reg_set_p (operands[3], operands[4])
    && peep2_regno_dead_p (0, FLAGS_REG)"
   [(parallel [(set (match_dup 5) (match_dup 0))
@@ -12861,6 +12864,7 @@
     || operands_match_p (operands[2], operands[4]))
    && ! reg_overlap_mentioned_p (operands[4], operands[0])
    && ! reg_overlap_mentioned_p (operands[4], operands[1])
+   && ! reg_overlap_mentioned_p (operands[4], operands[5])
    && ! reg_set_p (operands[4], operands[5])
    && refers_to_regno_p (FLAGS_REG, operands[1], (rtx *)NULL)
    && peep2_regno_dead_p (0, FLAGS_REG)"

gcc/testsuite/ChangeLog

 2018-06-26  Jakub Jelinek  <jakub@redhat.com>
 
+	PR target/86314
+	* gcc.dg/pr86314.c: New test.
+
 	PR debug/86257
 	* gcc.target/i386/pr86257.c: Add -mtls-dialect=gnu to dg-options.
 

gcc/testsuite/gcc.dg/pr86314.c

+// PR target/86314
+// { dg-do run { target sync_int_long } }
+// { dg-options "-O2" }
+
+__attribute__((noinline, noclone)) unsigned long
+foo (unsigned long *p)
+{
+  unsigned long m = 1UL << ((*p & 1) ? 1 : 0);
+  unsigned long n = __atomic_fetch_or (p, m, __ATOMIC_SEQ_CST);
+  return (n & m) == 0;
+}
+
+int
+main ()
+{
+  unsigned long v = 1;
+  if (foo (&v) != 1)
+    __builtin_abort ();
+  return 0;
+}