X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Ftv%2Ftv.c;h=90d24bb7ad3bd40faa932986cb3544f0d5de6553;hb=464132f4d8840f7bb4228bfeef5484331bf50835;hp=5015ad2d648290a183d62ddbeb788eb6e57ebffe;hpb=1231c62d9c8be4cd4929dbcc2f8e4e6a218ad062;p=libfirm

diff --git a/ir/tv/tv.c b/ir/tv/tv.c
index 5015ad2d6..90d24bb7a 100644
--- a/ir/tv/tv.c
+++ b/ir/tv/tv.c
@@ -191,13 +191,8 @@ static tarval *get_tarval_overflow(const void *value, int length, ir_mode *mode)
           case TV_OVERFLOW_WRAP:
             {
               char *temp = alloca(sc_get_buffer_length());
-              char *diff = alloca(sc_get_buffer_length());
-              sc_sub(get_mode_max(mode)->value, get_mode_min(mode)->value, diff);
-              sc_val_from_ulong(1, temp);
-              sc_add(diff, temp, diff);
-              sc_sub(value, diff, temp);
-              while (sc_comp(temp, get_mode_max(mode)->value) == 1)
-                sc_sub(temp, diff, temp);
+              sc_val_from_ulong(-1, temp);
+              sc_and(temp, value, temp);
               return get_tarval(temp, length, mode);
             }
           case TV_OVERFLOW_BAD:
@@ -213,13 +208,8 @@ static tarval *get_tarval_overflow(const void *value, int length, ir_mode *mode)
           case TV_OVERFLOW_WRAP:
             {
               char *temp = alloca(sc_get_buffer_length());
-              char *diff = alloca(sc_get_buffer_length());
-              sc_sub(get_mode_max(mode)->value, get_mode_min(mode)->value, diff);
-              sc_val_from_ulong(1, temp);
-              sc_add(diff, temp, diff);
-              sc_add(value, diff, temp);
-              while (sc_comp(temp, get_mode_max(mode)->value) == 1)
-                sc_add(temp, diff, temp);
+              sc_val_from_ulong(-1, temp);
+              sc_and(temp, value, temp);
               return get_tarval(temp, length, mode);
             }
           case TV_OVERFLOW_BAD:
@@ -241,6 +231,7 @@ static tarval *get_tarval_overflow(const void *value, int length, ir_mode *mode)
         return get_mode_null(mode);
       }
       break;
+
     default:
       break;
   }
@@ -251,13 +242,12 @@ static tarval *get_tarval_overflow(const void *value, int length, ir_mode *mode)
 /*
  *   public variables declared in tv.h
  */
-static tarval reserved_tv[5];
+static tarval reserved_tv[4];
 
 tarval *tarval_bad       = &reserved_tv[0];
 tarval *tarval_undefined = &reserved_tv[1];
 tarval *tarval_b_false   = &reserved_tv[2];
 tarval *tarval_b_true    = &reserved_tv[3];
-tarval *tarval_P_void    = &reserved_tv[4];
 
 /*
  *   public functions declared in tv.h
@@ -303,13 +293,12 @@ tarval *new_tarval_from_str(const char *str, size_t len, ir_mode *mode)
       }
       return get_tarval(fc_get_buffer(), fc_get_buffer_length(), mode);
 
+    case irms_reference:
+      /* same as integer modes */
     case irms_int_number:
     case irms_character:
       sc_val_from_str(str, len, NULL, mode);
       return get_tarval(sc_get_buffer(), sc_get_buffer_length(), mode);
-
-    case irms_reference:
-      return get_tarval(str, len, mode);
   }
 
   assert(0);  /* can't be reached, can it? */
@@ -330,6 +319,8 @@ tarval *new_tarval_from_long(long l, ir_mode *mode)
       /* XXX C semantics ! */
       return l ? tarval_b_true : tarval_b_false ;
 
+    case irms_reference:
+      /* same as integer modes */
     case irms_int_number:
     case irms_character:
       sc_val_from_long(l, NULL);
@@ -338,9 +329,6 @@ tarval *new_tarval_from_long(long l, ir_mode *mode)
     case irms_float_number:
       return new_tarval_from_double((long double)l, mode);
 
-    case irms_reference:
-      return l ? tarval_bad : get_tarval(NULL, 0, mode);  /* null pointer or tarval_bad */
-
     default:
       assert(0 && "unsupported mode sort");
   }
@@ -449,10 +437,6 @@ tarval *(get_tarval_b_true)(void) {
   return _get_tarval_b_true();
 }
 
-tarval *(get_tarval_P_void)(void) {
-  return _get_tarval_P_void();
-}
-
 tarval *get_tarval_max(ir_mode *mode)
 {
   ANNOUNCE();
@@ -543,6 +527,8 @@ tarval *get_tarval_min(ir_mode *mode)
   return tarval_bad;
 }
 
+static long _null_value;
+
 tarval *get_tarval_null(ir_mode *mode)
 {
   ANNOUNCE();
@@ -570,7 +556,7 @@ tarval *get_tarval_null(ir_mode *mode)
       return new_tarval_from_long(0l,  mode);
 
     case irms_reference:
-      return tarval_P_void;
+      return new_tarval_from_long(_null_value, mode);
   }
   return tarval_bad;
 }
@@ -949,13 +935,13 @@ tarval *tarval_convert_to(tarval *src, ir_mode *m)
               break;
           }
           return get_tarval(fc_get_buffer(), fc_get_buffer_length(), m);
-#if 0
+
         case irms_reference:
           /* allow 0 to be casted */
           if (src == get_mode_null(src->mode))
             return get_mode_null(m);
           break;
-#endif
+
         default:
           break;
       }
@@ -1524,21 +1510,21 @@ int tarval_snprintf(char *buf, size_t len, tarval *tv)
       break;
 
     case irms_reference:
-      if (tv == tarval_P_void) return snprintf(buf, len, "NULL");
-      if (tv->value != NULL){
-      if (len > tv->length) {
-        memcpy(buf, tv->value, tv->length);
-        buf[tv->length] = '\0';
-      }
-      else {
-        /* truncated */
-        memcpy(buf, tv->value, len-1);
-        buf[len-1] = '\0';
+      if (tv == tv->mode->null) return snprintf(buf, len, "NULL");
+      if (tv->value != NULL) {
+        if (len > tv->length) {
+          memcpy(buf, tv->value, tv->length);
+          buf[tv->length] = '\0';
+        }
+        else {
+          /* truncated */
+          memcpy(buf, tv->value, len-1);
+          buf[len-1] = '\0';
+        }
+        return tv->length;
       }
-      return tv->length;
-         }
       else
-    return snprintf(buf, len, "void");
+        return snprintf(buf, len, "void");
 
     case irms_internal_boolean:
       switch (mode_info->mode_output) {
@@ -1647,7 +1633,7 @@ const tarval_mode_info *get_tarval_mode_output_option(ir_mode *mode)
  * Identifying tarvals values for algebraic simplifications.
  *
  * Returns:
- *   - TV_CLASSIFY_NULL    for additive neutral,
+ *   - TV_CLASSIFY_NULL    for additive neutral or the NULL tarval for reference modes,
  *   - TV_CLASSIFY_ONE     for multiplicative neutral,
  *   - TV_CLASSIFY_ALL_ONE for bitwise-and neutral
  *   - TV_CLASSIFY_OTHER   else
@@ -1668,7 +1654,33 @@ tarval_classification_t classify_tarval(tarval *tv)
   return TV_CLASSIFY_OTHER;
 }
 
-/**
+/*
+ * Returns non-zero if a given (integer) tarval has only one single bit
+ * set.
+ */
+int is_single_bit_tarval(tarval *tv) {
+  int i, l;
+  int bits;
+
+  if (!tv || tv == tarval_bad) return 0;
+  if (! mode_is_int(tv->mode)) return 0;
+
+  l = get_mode_size_bytes(tv->mode);
+  for (bits = 0, i = l - 1; i >= 0; --i) {
+    unsigned char v = get_tarval_sub_bits(tv, (unsigned)i);
+
+    /* check for more than one bit in these */
+    if (v) {
+      if (v & (v-1))
+        return 0;
+      if (++bits > 1)
+        return 0;
+    }
+  }
+  return bits;
+}
+
+/*
  * Sets the overflow mode for integer operations.
  */
 void tarval_set_integer_overflow_mode(tarval_int_overflow_mode_t ov_mode) {
@@ -1700,13 +1712,14 @@ static const tarval_mode_info reference_output = {
   ")",
 };
 
-
 /*
  * Initialization of the tarval module: called before init_mode()
  */
-void init_tarval_1(void)
+void init_tarval_1(long null_value)
 {
   ANNOUNCE();
+  _null_value = null_value;
+
   /* initialize the sets holding the tarvals with a comparison function and
    * an initial size, which is the expected number of constants */
   tarvals = new_set(memcmp, N_CONSTANTS);
@@ -1736,9 +1749,6 @@ void init_tarval_2(void)
   tarval_b_false->kind   = k_tarval;
   tarval_b_false->mode   = mode_b;
 
-  tarval_P_void->kind    = k_tarval;
-  tarval_P_void->mode    = mode_P;
-
   /*
    * assign output modes that are compatible with the
    * old implementation: Hex output