defaults.h (IBM_FLOAT_FORMAT): Macro definition removed.

2007-05-21  Andreas Krebbel  <krebbel1@de.ibm.com>

	* defaults.h (IBM_FLOAT_FORMAT): Macro definition removed.
	* doc/tm.texi (IBM_FLOAT_FORMAT): Documentation entry removed.
	* real.c (encode_i370_single, decode_i370_single,
	encode_i370_double, decode_i370_double): Functions removed.
	(i370_single_format, i370_double_format): Initializations removed.
	(real_maxval, round_for_format, exact_real_truncate, significand_size):
	Consider the log2_b field to always be one.
	(ieee_single_format, mips_single_format, coldfire_single_format,
	ieee_double_format, mips_double_format,	coldfire_double_format,
	ieee_extended_motorola_format, ieee_extended_intel_96_format,
	ieee_extended_intel_128_format, ieee_extended_intel_96_round_53_format,
	ibm_extended_format, mips_extended_format, ieee_quad_format,
	mips_quad_format, vax_f_format, vax_d_format, vax_g_format,
	decimal_single_format, decimal_double_format, decimal_quad_format,
	c4x_single_format, c4x_extended_format, real_internal_format): Remove
	initialization of log2_b.
	* real.h (i370_single_format, i370_double_format): Declarations removed.
	* c-cppbuiltin.c (builtin_define_float_constants): Consider the log2_b
	field to always be one.

From-SVN: r124901

6 files changed, 38 insertions, 279 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 1943359..32ff87b 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,25 @@
+2007-05-21  Andreas Krebbel  <krebbel1@de.ibm.com>
+
+	* defaults.h (IBM_FLOAT_FORMAT): Macro definition removed.
+	* doc/tm.texi (IBM_FLOAT_FORMAT): Documentation entry removed.
+	* real.c (encode_i370_single, decode_i370_single,
+	encode_i370_double, decode_i370_double): Functions removed.
+	(i370_single_format, i370_double_format): Initializations removed.
+	(real_maxval, round_for_format, exact_real_truncate, significand_size):
+	Consider the log2_b field to always be one.
+	(ieee_single_format, mips_single_format, coldfire_single_format,
+	ieee_double_format, mips_double_format,	coldfire_double_format,
+	ieee_extended_motorola_format, ieee_extended_intel_96_format,
+	ieee_extended_intel_128_format, ieee_extended_intel_96_round_53_format,
+	ibm_extended_format, mips_extended_format, ieee_quad_format,
+	mips_quad_format, vax_f_format, vax_d_format, vax_g_format,
+	decimal_single_format, decimal_double_format, decimal_quad_format,
+	c4x_single_format, c4x_extended_format, real_internal_format): Remove
+	initialization of log2_b.
+	* real.h (i370_single_format, i370_double_format): Declarations removed.
+	* c-cppbuiltin.c (builtin_define_float_constants): Consider the log2_b
+	field to always be one.
+
 2007-05-21  Andreas Schwab  <schwab@suse.de>
 
 	* config/ia64/ia64.c (emit_predicate_relation_info): Fix use of
diff --git a/gcc/c-cppbuiltin.c b/gcc/c-cppbuiltin.c
index cc19ce5..544050a 100644
--- a/gcc/c-cppbuiltin.c
+++ b/gcc/c-cppbuiltin.c
@@ -111,7 +111,7 @@ builtin_define_float_constants (const char *name_prefix,
   /* The radix of the exponent representation.  */
   if (type == float_type_node)
     builtin_define_with_int_value ("__FLT_RADIX__", fmt->b);
-  log10_b = log10_2 * fmt->log2_b;
+  log10_b = log10_2;
 
   /* The number of radix digits, p, in the floating-point significand.  */
   sprintf (name, "__%s_MANT_DIG__", name_prefix);
@@ -208,12 +208,12 @@ builtin_define_float_constants (const char *name_prefix,
     char *p;
 
     strcpy (buf, "0x0.");
-    n = fmt->p * fmt->log2_b;
+    n = fmt->p;
     for (i = 0, p = buf + 4; i + 3 < n; i += 4)
       *p++ = 'f';
     if (i < n)
       *p++ = "08ce"[n - i];
-    sprintf (p, "p%d", fmt->emax * fmt->log2_b);
+    sprintf (p, "p%d", fmt->emax);
     if (fmt->pnan < fmt->p)
       {
 	/* This is an IBM extended double format made up of two IEEE
@@ -231,7 +231,7 @@ builtin_define_float_constants (const char *name_prefix,
   /* The minimum normalized positive floating-point number,
      b**(emin-1).  */
   sprintf (name, "__%s_MIN__", name_prefix);
-  sprintf (buf, "0x1p%d", (fmt->emin - 1) * fmt->log2_b);
+  sprintf (buf, "0x1p%d", fmt->emin - 1);
   builtin_define_with_hex_fp_value (name, type, decimal_dig, buf, fp_suffix, fp_cast);
 
   /* The difference between 1 and the least value greater than 1 that is
@@ -240,9 +240,9 @@ builtin_define_float_constants (const char *name_prefix,
   if (fmt->pnan < fmt->p)
     /* This is an IBM extended double format, so 1.0 + any double is
        representable precisely.  */
-      sprintf (buf, "0x1p%d", (fmt->emin - fmt->p) * fmt->log2_b);
+      sprintf (buf, "0x1p%d", fmt->emin - fmt->p);
     else
-      sprintf (buf, "0x1p%d", (1 - fmt->p) * fmt->log2_b);
+      sprintf (buf, "0x1p%d", 1 - fmt->p);
   builtin_define_with_hex_fp_value (name, type, decimal_dig, buf, fp_suffix, fp_cast);
 
   /* For C++ std::numeric_limits<T>::denorm_min.  The minimum denormalized
@@ -251,7 +251,7 @@ builtin_define_float_constants (const char *name_prefix,
   sprintf (name, "__%s_DENORM_MIN__", name_prefix);
   if (fmt->has_denorm)
     {
-      sprintf (buf, "0x1p%d", (fmt->emin - fmt->p) * fmt->log2_b);
+      sprintf (buf, "0x1p%d", fmt->emin - fmt->p);
       builtin_define_with_hex_fp_value (name, type, decimal_dig,
 					buf, fp_suffix, fp_cast);
     }
diff --git a/gcc/defaults.h b/gcc/defaults.h
index ed1ae39..e3de82a 100644
--- a/gcc/defaults.h
+++ b/gcc/defaults.h
@@ -623,8 +623,7 @@ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
 #define UNKNOWN_FLOAT_FORMAT 0
 #define IEEE_FLOAT_FORMAT 1
 #define VAX_FLOAT_FORMAT 2
-#define IBM_FLOAT_FORMAT 3
-#define C4X_FLOAT_FORMAT 4
+#define C4X_FLOAT_FORMAT 3
 
 /* Default to IEEE float if not specified.  Nearly all machines use it.  */
 #ifndef TARGET_FLOAT_FORMAT
diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
index 7129118..98fe8bb 100644
--- a/gcc/doc/tm.texi
+++ b/gcc/doc/tm.texi
@@ -1340,9 +1340,6 @@ need to define @code{TARGET_FLOAT_FORMAT} when the format is IEEE@.
 This code indicates the ``F float'' (for @code{float}) and ``D float''
 or ``G float'' formats (for @code{double}) used on the VAX and PDP-11@.
 
-@item IBM_FLOAT_FORMAT
-This code indicates the format used on the IBM System/370.
-
 @item C4X_FLOAT_FORMAT
 This code indicates the format used on the TMS320C3x/C4x.
 @end ftable
diff --git a/gcc/real.c b/gcc/real.c
index 48d9e9e..f5d842e 100644
--- a/gcc/real.c
+++ b/gcc/real.c
@@ -65,12 +65,7 @@
    have guard digits or rounding, the computation of 10**exp can
    accumulate more than a few digits of error.  The previous incarnation
    of real.c successfully used a 144-bit fraction; given the current
-   layout of REAL_VALUE_TYPE we're forced to expand to at least 160 bits.
-
-   Target floating point models that use base 16 instead of base 2
-   (i.e. IBM 370), are handled during round_for_format, in which we
-   canonicalize the exponent to be a multiple of 4 (log2(16)), and
-   adjust the significand to match.  */
+   layout of REAL_VALUE_TYPE we're forced to expand to at least 160 bits.  */
 
 
 /* Used to classify two numbers simultaneously.  */
@@ -2282,9 +2277,9 @@ real_maxval (REAL_VALUE_TYPE *r, int sign, enum machine_mode mode)
     {
       r->cl = rvc_normal;
       r->sign = sign;
-      SET_REAL_EXP (r, fmt->emax * fmt->log2_b);
+      SET_REAL_EXP (r, fmt->emax);
 
-      np2 = SIGNIFICAND_BITS - fmt->p * fmt->log2_b;
+      np2 = SIGNIFICAND_BITS - fmt->p;
       memset (r->sig, -1, SIGSZ * sizeof (unsigned long));
       clear_significand_below (r, np2);
 
@@ -2342,9 +2337,9 @@ round_for_format (const struct real_format *fmt, REAL_VALUE_TYPE *r)
       decimal_real_convert (r, DFmode, r);
     }
 
-  p2 = fmt->p * fmt->log2_b;
-  emin2m1 = (fmt->emin - 1) * fmt->log2_b;
-  emax2 = fmt->emax * fmt->log2_b;
+  p2 = fmt->p;
+  emin2m1 = fmt->emin - 1;
+  emax2 = fmt->emax;
 
   np2 = SIGNIFICAND_BITS - p2;
   switch (r->cl)
@@ -2372,22 +2367,6 @@ round_for_format (const struct real_format *fmt, REAL_VALUE_TYPE *r)
       gcc_unreachable ();
     }
 
-  /* If we're not base2, normalize the exponent to a multiple of
-     the true base.  */
-  if (fmt->log2_b != 1)
-    {
-      int shift;
-
-      gcc_assert (fmt->b != 10);
-      shift = REAL_EXP (r) & (fmt->log2_b - 1);
-      if (shift)
-	{
-	  shift = fmt->log2_b - shift;
-	  r->sig[0] |= sticky_rshift_significand (r, r, shift);
-	  SET_REAL_EXP (r, REAL_EXP (r) + shift);
-	}
-    }
-
   /* Check the range of the exponent.  If we're out of range,
      either underflow or overflow.  */
   if (REAL_EXP (r) > emax2)
@@ -2443,19 +2422,6 @@ round_for_format (const struct real_format *fmt, REAL_VALUE_TYPE *r)
 	  if (REAL_EXP (r) > emax2)
 	    goto overflow;
 	  r->sig[SIGSZ-1] = SIG_MSB;
-
-	  if (fmt->log2_b != 1)
-	    {
-	      int shift = REAL_EXP (r) & (fmt->log2_b - 1);
-	      if (shift)
-		{
-		  shift = fmt->log2_b - shift;
-		  rshift_significand (r, r, shift);
-		  SET_REAL_EXP (r, REAL_EXP (r) + shift);
-		  if (REAL_EXP (r) > emax2)
-		    goto overflow;
-		}
-	    }
 	}
     }
 
@@ -2513,7 +2479,7 @@ exact_real_truncate (enum machine_mode mode, const REAL_VALUE_TYPE *a)
   gcc_assert (fmt);
 
   /* Don't allow conversion to denormals.  */
-  emin2m1 = (fmt->emin - 1) * fmt->log2_b;
+  emin2m1 = fmt->emin - 1;
   if (REAL_EXP (a) <= emin2m1)
     return false;
 
@@ -2604,7 +2570,7 @@ significand_size (enum machine_mode mode)
       double log2_10 = 3.3219281;
       return fmt->p * log2_10;
     }
-  return fmt->p * fmt->log2_b;
+  return fmt->p;
 }
 
 /* Return a hash value for the given real value.  */
@@ -2775,7 +2741,6 @@ const struct real_format ieee_single_format =
     encode_ieee_single,
     decode_ieee_single,
     2,
-    1,
     24,
     24,
     -125,
@@ -2795,7 +2760,6 @@ const struct real_format mips_single_format =
     encode_ieee_single,
     decode_ieee_single,
     2,
-    1,
     24,
     24,
     -125,
@@ -2815,7 +2779,6 @@ const struct real_format coldfire_single_format =
     encode_ieee_single,
     decode_ieee_single,
     2,
-    1,
     24,
     24,
     -125,
@@ -3023,7 +2986,6 @@ const struct real_format ieee_double_format =
     encode_ieee_double,
     decode_ieee_double,
     2,
-    1,
     53,
     53,
     -1021,
@@ -3043,7 +3005,6 @@ const struct real_format mips_double_format =
     encode_ieee_double,
     decode_ieee_double,
     2,
-    1,
     53,
     53,
     -1021,
@@ -3063,7 +3024,6 @@ const struct real_format coldfire_double_format =
     encode_ieee_double,
     decode_ieee_double,
     2,
-    1,
     53,
     53,
     -1021,
@@ -3393,7 +3353,6 @@ const struct real_format ieee_extended_motorola_format =
     encode_ieee_extended_motorola,
     decode_ieee_extended_motorola,
     2,
-    1,
     64,
     64,
     -16382,
@@ -3413,7 +3372,6 @@ const struct real_format ieee_extended_intel_96_format =
     encode_ieee_extended_intel_96,
     decode_ieee_extended_intel_96,
     2,
-    1,
     64,
     64,
     -16381,
@@ -3433,7 +3391,6 @@ const struct real_format ieee_extended_intel_128_format =
     encode_ieee_extended_intel_128,
     decode_ieee_extended_intel_128,
     2,
-    1,
     64,
     64,
     -16381,
@@ -3455,7 +3412,6 @@ const struct real_format ieee_extended_intel_96_round_53_format =
     encode_ieee_extended_intel_96,
     decode_ieee_extended_intel_96,
     2,
-    1,
     53,
     53,
     -16381,
@@ -3542,7 +3498,6 @@ const struct real_format ibm_extended_format =
     encode_ibm_extended,
     decode_ibm_extended,
     2,
-    1,
     53 + 53,
     53,
     -1021 + 53,
@@ -3562,7 +3517,6 @@ const struct real_format mips_extended_format =
     encode_ibm_extended,
     decode_ibm_extended,
     2,
-    1,
     53 + 53,
     53,
     -1021 + 53,
@@ -3824,7 +3778,6 @@ const struct real_format ieee_quad_format =
     encode_ieee_quad,
     decode_ieee_quad,
     2,
-    1,
     113,
     113,
     -16381,
@@ -3844,7 +3797,6 @@ const struct real_format mips_quad_format =
     encode_ieee_quad,
     decode_ieee_quad,
     2,
-    1,
     113,
     113,
     -16381,
@@ -4143,7 +4095,6 @@ const struct real_format vax_f_format =
     encode_vax_f,
     decode_vax_f,
     2,
-    1,
     24,
     24,
     -127,
@@ -4163,7 +4114,6 @@ const struct real_format vax_d_format =
     encode_vax_d,
     decode_vax_d,
     2,
-    1,
     56,
     56,
     -127,
@@ -4183,7 +4133,6 @@ const struct real_format vax_g_format =
     encode_vax_g,
     decode_vax_g,
     2,
-    1,
     53,
     53,
     -1023,
@@ -4198,203 +4147,6 @@ const struct real_format vax_g_format =
     false
   };
 
-/* A good reference for these can be found in chapter 9 of
-   "ESA/390 Principles of Operation", IBM document number SA22-7201-01.
-   An on-line version can be found here:
-
-   http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/DZ9AR001/9.1?DT=19930923083613
-*/
-
-static void encode_i370_single (const struct real_format *fmt,
-				long *, const REAL_VALUE_TYPE *);
-static void decode_i370_single (const struct real_format *,
-				REAL_VALUE_TYPE *, const long *);
-static void encode_i370_double (const struct real_format *fmt,
-				long *, const REAL_VALUE_TYPE *);
-static void decode_i370_double (const struct real_format *,
-				REAL_VALUE_TYPE *, const long *);
-
-static void
-encode_i370_single (const struct real_format *fmt ATTRIBUTE_UNUSED,
-		    long *buf, const REAL_VALUE_TYPE *r)
-{
-  unsigned long sign, exp, sig, image;
-
-  sign = r->sign << 31;
-
-  switch (r->cl)
-    {
-    case rvc_zero:
-      image = 0;
-      break;
-
-    case rvc_inf:
-    case rvc_nan:
-      image = 0x7fffffff | sign;
-      break;
-
-    case rvc_normal:
-      sig = (r->sig[SIGSZ-1] >> (HOST_BITS_PER_LONG - 24)) & 0xffffff;
-      exp = ((REAL_EXP (r) / 4) + 64) << 24;
-      image = sign | exp | sig;
-      break;
-
-    default:
-      gcc_unreachable ();
-    }
-
-  buf[0] = image;
-}
-
-static void
-decode_i370_single (const struct real_format *fmt ATTRIBUTE_UNUSED,
-		    REAL_VALUE_TYPE *r, const long *buf)
-{
-  unsigned long sign, sig, image = buf[0];
-  int exp;
-
-  sign = (image >> 31) & 1;
-  exp = (image >> 24) & 0x7f;
-  sig = image & 0xffffff;
-
-  memset (r, 0, sizeof (*r));
-
-  if (exp || sig)
-    {
-      r->cl = rvc_normal;
-      r->sign = sign;
-      SET_REAL_EXP (r, (exp - 64) * 4);
-      r->sig[SIGSZ-1] = sig << (HOST_BITS_PER_LONG - 24);
-      normalize (r);
-    }
-}
-
-static void
-encode_i370_double (const struct real_format *fmt ATTRIBUTE_UNUSED,
-		    long *buf, const REAL_VALUE_TYPE *r)
-{
-  unsigned long sign, exp, image_hi, image_lo;
-
-  sign = r->sign << 31;
-
-  switch (r->cl)
-    {
-    case rvc_zero:
-      image_hi = image_lo = 0;
-      break;
-
-    case rvc_inf:
-    case rvc_nan:
-      image_hi = 0x7fffffff | sign;
-      image_lo = 0xffffffff;
-      break;
-
-    case rvc_normal:
-      if (HOST_BITS_PER_LONG == 64)
-	{
-	  image_hi = r->sig[SIGSZ-1];
-	  image_lo = (image_hi >> (64 - 56)) & 0xffffffff;
-	  image_hi = (image_hi >> (64 - 56 + 1) >> 31) & 0xffffff;
-	}
-      else
-	{
-	  image_hi = r->sig[SIGSZ-1];
-	  image_lo = r->sig[SIGSZ-2];
-	  image_lo = (image_lo >> 8) | (image_hi << 24);
-	  image_hi >>= 8;
-	}
-
-      exp = ((REAL_EXP (r) / 4) + 64) << 24;
-      image_hi |= sign | exp;
-      break;
-
-    default:
-      gcc_unreachable ();
-    }
-
-  if (FLOAT_WORDS_BIG_ENDIAN)
-    buf[0] = image_hi, buf[1] = image_lo;
-  else
-    buf[0] = image_lo, buf[1] = image_hi;
-}
-
-static void
-decode_i370_double (const struct real_format *fmt ATTRIBUTE_UNUSED,
-		    REAL_VALUE_TYPE *r, const long *buf)
-{
-  unsigned long sign, image_hi, image_lo;
-  int exp;
-
-  if (FLOAT_WORDS_BIG_ENDIAN)
-    image_hi = buf[0], image_lo = buf[1];
-  else
-    image_lo = buf[0], image_hi = buf[1];
-
-  sign = (image_hi >> 31) & 1;
-  exp = (image_hi >> 24) & 0x7f;
-  image_hi &= 0xffffff;
-  image_lo &= 0xffffffff;
-
-  memset (r, 0, sizeof (*r));
-
-  if (exp || image_hi || image_lo)
-    {
-      r->cl = rvc_normal;
-      r->sign = sign;
-      SET_REAL_EXP (r, (exp - 64) * 4 + (SIGNIFICAND_BITS - 56));
-
-      if (HOST_BITS_PER_LONG == 32)
-	{
-	  r->sig[0] = image_lo;
-	  r->sig[1] = image_hi;
-	}
-      else
-	r->sig[0] = image_lo | (image_hi << 31 << 1);
-
-      normalize (r);
-    }
-}
-
-const struct real_format i370_single_format =
-  {
-    encode_i370_single,
-    decode_i370_single,
-    16,
-    4,
-    6,
-    6,
-    -64,
-    63,
-    31,
-    31,
-    false,
-    false,
-    false, /* ??? The encoding does allow for "unnormals".  */
-    false, /* ??? The encoding does allow for "unnormals".  */
-    false,
-    false
-  };
-
-const struct real_format i370_double_format =
-  {
-    encode_i370_double,
-    decode_i370_double,
-    16,
-    4,
-    14,
-    14,
-    -64,
-    63,
-    63,
-    63,
-    false,
-    false,
-    false, /* ??? The encoding does allow for "unnormals".  */
-    false, /* ??? The encoding does allow for "unnormals".  */
-    false,
-    false
-  };
-
 /* Encode real R into a single precision DFP value in BUF.  */
 static void
 encode_decimal_single (const struct real_format *fmt ATTRIBUTE_UNUSED,
@@ -4455,7 +4207,6 @@ const struct real_format decimal_single_format =
     encode_decimal_single,
     decode_decimal_single,
     10, 
-    1,  /* log10 */
     7,
     7,
     -95,
@@ -4476,7 +4227,6 @@ const struct real_format decimal_double_format =
     encode_decimal_double,
     decode_decimal_double,
     10,
-    1,  /* log10 */
     16,
     16,
     -383,
@@ -4497,7 +4247,6 @@ const struct real_format decimal_quad_format =
     encode_decimal_quad,
     decode_decimal_quad,
     10,
-    1,  /* log10 */
     34,
     34,
     -6143,
@@ -4707,7 +4456,6 @@ const struct real_format c4x_single_format =
     encode_c4x_single,
     decode_c4x_single,
     2,
-    1,
     24,
     24,
     -126,
@@ -4727,7 +4475,6 @@ const struct real_format c4x_extended_format =
     encode_c4x_extended,
     decode_c4x_extended,
     2,
-    1,
     32,
     32,
     -126,
@@ -4772,7 +4519,6 @@ const struct real_format real_internal_format =
     encode_internal,
     decode_internal,
     2,
-    1,
     SIGNIFICAND_BITS - 2,
     SIGNIFICAND_BITS - 2,
     -MAX_EXP,
diff --git a/gcc/real.h b/gcc/real.h
index 6fae225..f050daf 100644
--- a/gcc/real.h
+++ b/gcc/real.h
@@ -126,9 +126,6 @@ struct real_format
   /* The radix of the exponent and digits of the significand.  */
   int b;
 
-  /* log2(b).  */
-  int log2_b;
-
   /* Size of the significand in digits of radix B.  */
   int p;
 
@@ -272,8 +269,6 @@ extern const struct real_format mips_quad_format;
 extern const struct real_format vax_f_format;
 extern const struct real_format vax_d_format;
 extern const struct real_format vax_g_format;
-extern const struct real_format i370_single_format;
-extern const struct real_format i370_double_format;
 extern const struct real_format c4x_single_format;
 extern const struct real_format c4x_extended_format;
 extern const struct real_format real_internal_format;