re PR middle-end/26134 (fold *(float*)(&complex_float_var) into REALPART_EXPR<complex_float_var>)

2006-02-09  Andrew Pinski  <pinskia@physics.uc.edu>

        PR middle-end/26134
        * fold-const.c (fold_indirect_ref_1): Fold
        "*(foo *)&complexfoo" to "__real__ complexfoo"
        and "((foo*)&complexfoo)[1]" to "__imag__ complexfoo".
2006-02-09  Andrew Pinski  <pinskia@physics.uc.edu>

        PR middle-end/26134
        * gcc.dg/tree-ssa/complex-3.c: New test.

From-SVN: r110800

gcc/ChangeLog

 2006-02-09  Andrew Pinski  <pinskia@physics.uc.edu>
 
+	PR middle-end/26134
+	* fold-const.c (fold_indirect_ref_1): Fold 
+	"*(foo *)&complexfoo" to "__real__ complexfoo"
+	and "((foo*)&complexfoo)[1]" to "__imag__ complexfoo".
+
+2006-02-09  Andrew Pinski  <pinskia@physics.uc.edu>
+
 	* tree-flow-inline.h (var_can_have_subvars): 
 	Volatile variables should not have subvariables.
 

gcc/fold-const.c

@@ -11721,8 +11721,32 @@ fold_indirect_ref_1 (tree type, tree op0)
 	    min_val = TYPE_MIN_VALUE (type_domain);
 	  return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
 	}
+      /* *(foo *)&complexfoo => __real__ complexfoo */
+      else if (TREE_CODE (optype) == COMPLEX_TYPE
+	       && type == TREE_TYPE (optype))
+	return fold_build1 (REALPART_EXPR, type, op);
     }
 
+  /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
+  if (TREE_CODE (sub) == PLUS_EXPR
+      && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
+    {
+      tree op00 = TREE_OPERAND (sub, 0);
+      tree op01 = TREE_OPERAND (sub, 1);
+      tree op00type;
+
+      STRIP_NOPS (op00);
+      op00type = TREE_TYPE (op00);
+      if (TREE_CODE (op00) == ADDR_EXPR
+ 	  && TREE_CODE (TREE_TYPE (op00type)) == COMPLEX_TYPE
+	  && type == TREE_TYPE (TREE_TYPE (op00type)))
+	{
+	  tree size = TYPE_SIZE_UNIT (type);
+	  if (tree_int_cst_equal (size, op01))
+	    return fold_build1 (IMAGPART_EXPR, type, TREE_OPERAND (op00, 0));
+	}
+    }
+  
   /* *(foo *)fooarrptr => (*fooarrptr)[0] */
   if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
       && type == TREE_TYPE (TREE_TYPE (subtype)))

gcc/testsuite/ChangeLog

 2006-02-09  Andrew Pinski  <pinskia@physics.uc.edu>
 
+	PR middle-end/26134
+	* gcc.dg/tree-ssa/complex-3.c: New test.
+
+2006-02-09  Andrew Pinski  <pinskia@physics.uc.edu>
+
 	* gcc.c-torture/compile/volatile-1.c: New test.
 
 2006-02-09  Diego Novillo  <dnovillo@redhat.com>

gcc/testsuite/gcc.dg/tree-ssa/complex-3.c

+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-optimized" } */
+
+typedef _Complex float COMPLEX_FLOAT;
+float real_part(COMPLEX_FLOAT a)
+{
+  return *(float*)(&a);
+}
+
+float real_part_2(COMPLEX_FLOAT a)
+{
+  return ((float*)(&a))[0];
+}
+
+
+float imag_part(COMPLEX_FLOAT a)
+{
+  return ((float*)(&a))[1];
+}
+
+/* Test that the above gets optimized to REALPART_EXPR and IMAGPART_EXPR
+   respectively. */
+
+/* { dg-final { scan-tree-dump-times "REALPART_EXPR" 2 "optimized" } } */
+/* { dg-final { scan-tree-dump-times "IMAGPART_EXPR" 1 "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
+