re PR target/70903 (wrong code with bfi @ aarch64 with -Os)

2016-08-04  Bernd Edlinger  <bernd.edlinger@hotmail.de>

        PR rtl-optimization/70903
        * cse.c (cse_insn): If DEST is a paradoxical SUBREG, don't record DEST.

testsuite:
2016-08-04  Bernd Edlinger  <bernd.edlinger@hotmail.de>

        PR rtl-optimization/70903
        * gcc.c-torture/execute/pr70903.c: New test.

From-SVN: r239122

gcc/ChangeLog

+2016-08-04  Bernd Edlinger  <bernd.edlinger@hotmail.de>
+
+	PR rtl-optimization/70903
+	* cse.c (cse_insn): If DEST is a paradoxical SUBREG, don't record DEST.
+
 2016-08-04  Kugan Vivekanandarajah  <kuganv@linaro.org>
 
 	* tree-inline.c (remap_ssa_name): Check for POINTER_TYPE_P before

gcc/cse.c

@@ -5898,15 +5898,7 @@ cse_insn (rtx_insn *insn)
 	    || GET_MODE (dest) == BLKmode
 	    /* If we didn't put a REG_EQUAL value or a source into the hash
 	       table, there is no point is recording DEST.  */
-	    || sets[i].src_elt == 0
-	    /* If DEST is a paradoxical SUBREG and SRC is a ZERO_EXTEND
-	       or SIGN_EXTEND, don't record DEST since it can cause
-	       some tracking to be wrong.
-
-	       ??? Think about this more later.  */
-	    || (paradoxical_subreg_p (dest)
-		&& (GET_CODE (sets[i].src) == SIGN_EXTEND
-		    || GET_CODE (sets[i].src) == ZERO_EXTEND)))
+	    || sets[i].src_elt == 0)
 	  continue;
 
 	/* STRICT_LOW_PART isn't part of the value BEING set,
@@ -5925,6 +5917,11 @@ cse_insn (rtx_insn *insn)
 	      sets[i].dest_hash = HASH (dest, GET_MODE (dest));
 	    }
 
+	/* If DEST is a paradoxical SUBREG, don't record DEST since the bits
+	   outside the mode of GET_MODE (SUBREG_REG (dest)) are undefined.  */
+	if (paradoxical_subreg_p (dest))
+	  continue;
+
 	elt = insert (dest, sets[i].src_elt,
 		      sets[i].dest_hash, GET_MODE (dest));
 

gcc/testsuite/ChangeLog

+2016-08-04  Bernd Edlinger  <bernd.edlinger@hotmail.de>
+
+	PR rtl-optimization/70903
+	* gcc.c-torture/execute/pr70903.c: New test.
+
 2016-08-04  Martin Liska  <mliska@suse.cz>
 
 	* gcc.dg/params/params.exp: Replace file exists with

gcc/testsuite/gcc.c-torture/execute/pr70903.c

+typedef unsigned char V8 __attribute__ ((vector_size (32)));
+typedef unsigned int V32 __attribute__ ((vector_size (32)));
+typedef unsigned long long V64 __attribute__ ((vector_size (32)));
+
+static V32 __attribute__ ((noinline, noclone))
+foo (V64 x)
+{
+  V64 y = (V64)(V8){((V8)(V64){65535, x[0]})[1]};
+  return (V32){y[0], 255};
+}
+
+int main ()
+{
+  V32 x = foo ((V64){});
+//  __builtin_printf ("%08x %08x %08x %08x %08x %08x %08x %08x\n", x[0], x[1], x[2], x[3], x[4], x[5], x[6], x[7]);
+  if (x[1] != 255)
+    __builtin_abort();
+  return 0;
+}
+typedef unsigned char V8 __attribute__ ((vector_size (32)));
+typedef unsigned int V32 __attribute__ ((vector_size (32)));
+typedef unsigned long long V64 __attribute__ ((vector_size (32)));
+
+static V32 __attribute__ ((noinline, noclone))
+foo (V64 x)
+{
+  V64 y = (V64)(V8){((V8)(V64){65535, x[0]})[1]};
+  return (V32){y[0], 255};
+}
+
+int main ()
+{
+  V32 x = foo ((V64){});
+//  __builtin_printf ("%08x %08x %08x %08x %08x %08x %08x %08x\n", x[0], x[1], x[2], x[3], x[4], x[5], x[6], x[7]);
+  if (x[1] != 255)
+    __builtin_abort();
+  return 0;
+}