(fold): Handle complex constants as "winning".

Handle REALPART_EXPR and IMAGPART_EXPR.

From-SVN: r3637

diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 48892bc43b2ab759355325929173d122d3048c0d..9e2fb8237751309b50d221172d195583ad389490 100644 (file)
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -2994,6 +2994,8 @@ fold (expr)
   kind = TREE_CODE_CLASS (code);
   if (code == NOP_EXPR || code == FLOAT_EXPR || code == CONVERT_EXPR)
     {
+      tree subop;
+
       /* Special case for conversion ops that can have fixed point args.  */
       arg0 = TREE_OPERAND (t, 0);
 
@@ -3001,9 +3003,14 @@ fold (expr)
       if (arg0 != 0)
        STRIP_TYPE_NOPS (arg0);
 
-      if (arg0 != 0 && TREE_CODE (arg0) != INTEGER_CST
+      if (arg0 != 0 && TREE_CODE (arg0) == COMPLEX_CST)
+       subop = TREE_REALPART (arg0);
+      else
+       subop = arg0;
+
+      if (subop != 0 && TREE_CODE (subop) != INTEGER_CST
 #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
-         && TREE_CODE (arg0) != REAL_CST
+         && TREE_CODE (subop) != REAL_CST
 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
          )
        /* Note that TREE_CONSTANT isn't enough:
@@ -3019,6 +3026,7 @@ fold (expr)
       for (i = 0; i < len; i++)
        {
          tree op = TREE_OPERAND (t, i);
+         tree subop;
 
          if (op == 0)
            continue;           /* Valid for CALL_EXPR, at least.  */
@@ -3026,9 +3034,14 @@ fold (expr)
          /* Strip any conversions that don't change the mode.  */
          STRIP_NOPS (op);
          
-         if (TREE_CODE (op) != INTEGER_CST
+         if (TREE_CODE (op) == COMPLEX_CST)
+           subop = TREE_REALPART (op);
+         else
+           subop = op;
+
+         if (TREE_CODE (subop) != INTEGER_CST
 #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
-             && TREE_CODE (op) != REAL_CST
+             && TREE_CODE (subop) != REAL_CST
 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
              )
            /* Note that TREE_CONSTANT isn't enough:
@@ -4384,6 +4397,49 @@ fold (expr)
        return non_lvalue (arg1);
       return arg1;
 
+    case COMPLEX_EXPR:
+      if (wins)
+       return build_complex (arg0, arg1);
+      return t;
+
+    case REALPART_EXPR:
+      if (TREE_CODE (type) != COMPLEX_TYPE)
+       return t;
+      else if (TREE_CODE (arg0) == COMPLEX_EXPR)
+       return omit_one_operand (type, TREE_OPERAND (arg0, 0),
+                                TREE_OPERAND (arg0, 1));
+      else if (TREE_CODE (arg0) == COMPLEX_CST)
+       return TREE_REALPART (arg0);
+      else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
+       return build_binary_op (TREE_CODE (arg0), type,
+                               build_unary_op (REALPART_EXPR,
+                                               TREE_OPERAND (arg0, 0),
+                                               1),
+                               build_unary_op (REALPART_EXPR,
+                                               TREE_OPERAND (arg0, 1),
+                                               1),
+                               0);
+      return t;
+
+    case IMAGPART_EXPR:
+      if (TREE_CODE (type) != COMPLEX_TYPE)
+       return convert (type, integer_zero_node);
+      else if (TREE_CODE (arg0) == COMPLEX_EXPR)
+       return omit_one_operand (type, TREE_OPERAND (arg0, 1),
+                                TREE_OPERAND (arg0, 0));
+      else if (TREE_CODE (arg0) == COMPLEX_CST)
+       return TREE_IMAGPART (arg0);
+      else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
+       return build_binary_op (TREE_CODE (arg0), type,
+                               build_unary_op (IMAGPART_EXPR,
+                                               TREE_OPERAND (arg0, 0),
+                                               1),
+                               build_unary_op (IMAGPART_EXPR,
+                                               TREE_OPERAND (arg0, 1),
+                                               1),
+                               0);
+      return t;
+
     default:
       return t;
     } /* switch (code) */