re PR tree-optimization/61517 (wrong code at -Os and above on x86_64-linux-gnu)

2014-06-18  Thomas Preud'homme  <thomas.preudhomme@arm.com>

    gcc/
    PR tree-optimization/61517
    * tree-ssa-math-opts.c (find_bswap_or_nop_1): Adapt to return a stmt
    whose rhs's first tree is the source expression instead of the
    expression itself.
    (find_bswap_or_nop): Likewise.
    (bsap_replace): Rename stmt in cur_stmt. Pass gsi by value and src as a
    gimple stmt whose rhs's first tree is the source. In the memory source
    case, move the stmt to be replaced close to one of the original load to
    avoid the problem of a store between the load and the stmt's original
    location.
    (pass_optimize_bswap::execute): Adapt to change in bswap_replace's
    signature.

    gcc/testsuite/
    * gcc.c-torture/execute/bswap-2.c (incorrect_read_le32): New.
    (incorrect_read_be32): Likewise.
    (main): Call incorrect_read_* to test stmt replacement is made by
    bswap at the right place.
    * gcc.c-torture/execute/pr61517.c: New test.

From-SVN: r211778

gcc/ChangeLog

+2014-06-18  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+	PR tree-optimization/61517
+	* tree-ssa-math-opts.c (find_bswap_or_nop_1): Adapt to return a stmt
+	whose rhs's first tree is the source expression instead of the
+	expression itself.
+	(find_bswap_or_nop): Likewise.
+	(bsap_replace): Rename stmt in cur_stmt. Pass gsi by value and src as a
+	gimple stmt whose rhs's first tree is the source. In the memory source
+	case, move the stmt to be replaced close to one of the original load to
+	avoid the problem of a store between the load and the stmt's original
+	location.
+	(pass_optimize_bswap::execute): Adapt to change in bswap_replace's
+	signature.
+
 2014-06-18  Andreas Schwab  <schwab@suse.de>
 
 	PR rtl-optimization/54555

gcc/testsuite/ChangeLog

+2014-06-18  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+	PR tree-optimization/61517
+	* gcc.c-torture/execute/bswap-2.c (incorrect_read_le32): New.
+	(incorrect_read_be32): Likewise.
+	(main): Call incorrect_read_* to test stmt replacement is made by
+	bswap at the right place.
+	* gcc.c-torture/execute/pr61517.c: New test.
+
 2014-06-18  Andreas Schwab  <schwab@suse.de>
 
 	PR rtl-optimization/54555

gcc/testsuite/gcc.c-torture/execute/bswap-2.c

@@ -66,6 +66,32 @@ fake_read_be32 (char *x, char *y)
   return c3 | c2 << 8 | c1 << 16 | c0 << 24;
 }
 
+__attribute__ ((noinline, noclone)) uint32_t
+incorrect_read_le32 (char *x, char *y)
+{
+  unsigned char c0, c1, c2, c3;
+
+  c0 = x[0];
+  c1 = x[1];
+  c2 = x[2];
+  c3 = x[3];
+  *y = 1;
+  return c0 | c1 << 8 | c2 << 16 | c3 << 24;
+}
+
+__attribute__ ((noinline, noclone)) uint32_t
+incorrect_read_be32 (char *x, char *y)
+{
+  unsigned char c0, c1, c2, c3;
+
+  c0 = x[0];
+  c1 = x[1];
+  c2 = x[2];
+  c3 = x[3];
+  *y = 1;
+  return c3 | c2 << 8 | c1 << 16 | c0 << 24;
+}
+
 int
 main ()
 {
@@ -92,8 +118,17 @@ main ()
   out = fake_read_le32 (cin, &cin[2]);
   if (out != 0x89018583)
     __builtin_abort ();
+  cin[2] = 0x87;
   out = fake_read_be32 (cin, &cin[2]);
   if (out != 0x83850189)
     __builtin_abort ();
+  cin[2] = 0x87;
+  out = incorrect_read_le32 (cin, &cin[2]);
+  if (out != 0x89878583)
+    __builtin_abort ();
+  cin[2] = 0x87;
+  out = incorrect_read_be32 (cin, &cin[2]);
+  if (out != 0x83858789)
+    __builtin_abort ();
   return 0;
 }

gcc/testsuite/gcc.c-torture/execute/pr61517.c

+int a, b, *c = &a;
+unsigned short d;
+
+int
+main ()
+{
+  unsigned int e = a;
+  *c = 1;
+  if (!b)
+    {
+      d = e;
+      *c = d | e;
+    }
+
+  if (a != 0)
+    __builtin_abort ();
+
+  return 0;
+}