(decimal_)float_mode_for_size in real.h

This patch makes the binary float macros in real.h use
float_mode_for_size and adds a corresponding decimal_float_mode_for_size
for the decimal macros.

2017-09-05  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
	* machmode.h (decimal_float_mode_for_size): New function.
	* real.h (REAL_VALUE_TO_TARGET_LONG_DOUBLE): Use float_mode_for_size.
	(REAL_VALUE_TO_TARGET_DOUBLE): Likewise.
	(REAL_VALUE_TO_TARGET_SINGLE): Likewise.
	(REAL_VALUE_TO_TARGET_DECIMAL128): Use decimal_float_mode_for_size.
	(REAL_VALUE_TO_TARGET_DECIMAL64): Likewise.
	(REAL_VALUE_TO_TARGET_DECIMAL32): Likewise.

From-SVN: r251727

3 files changed, 26 insertions, 6 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8105f3d..7fbade7 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,15 @@
 2017-09-05  Richard Sandiford  <richard.sandiford@linaro.org>
 
+	* machmode.h (decimal_float_mode_for_size): New function.
+	* real.h (REAL_VALUE_TO_TARGET_LONG_DOUBLE): Use float_mode_for_size.
+	(REAL_VALUE_TO_TARGET_DOUBLE): Likewise.
+	(REAL_VALUE_TO_TARGET_SINGLE): Likewise.
+	(REAL_VALUE_TO_TARGET_DECIMAL128): Use decimal_float_mode_for_size.
+	(REAL_VALUE_TO_TARGET_DECIMAL64): Likewise.
+	(REAL_VALUE_TO_TARGET_DECIMAL32): Likewise.
+
+2017-09-05  Richard Sandiford  <richard.sandiford@linaro.org>
+
 	* builtins.c (expand_builtin_powi): Use int_mode_for_size.
 	(get_builtin_sync_mode): Likewise.
 	(expand_ifn_atomic_compare_exchange): Likewise.
diff --git a/gcc/machmode.h b/gcc/machmode.h
index b331f07..d8344a9 100644
--- a/gcc/machmode.h
+++ b/gcc/machmode.h
@@ -652,6 +652,15 @@ float_mode_for_size (unsigned int size)
   return dyn_cast <scalar_float_mode> (mode_for_size (size, MODE_FLOAT, 0));
 }
 
+/* Likewise for MODE_DECIMAL_FLOAT.  */
+
+inline opt_scalar_float_mode
+decimal_float_mode_for_size (unsigned int size)
+{
+  return dyn_cast <scalar_float_mode>
+    (mode_for_size (size, MODE_DECIMAL_FLOAT, 0));
+}
+
 /* Similar to mode_for_size, but find the smallest mode for a given width.  */
 
 extern machine_mode smallest_mode_for_size (unsigned int, enum mode_class);
diff --git a/gcc/real.h b/gcc/real.h
index 95104b0..c034fd9 100644
--- a/gcc/real.h
+++ b/gcc/real.h
@@ -383,27 +383,28 @@ extern const struct real_format arm_half_format;
 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT)			\
   real_to_target (OUT, &(IN),						\
-		  mode_for_size (LONG_DOUBLE_TYPE_SIZE, MODE_FLOAT, 0))
+		  float_mode_for_size (LONG_DOUBLE_TYPE_SIZE).require ())
 
 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) \
-  real_to_target (OUT, &(IN), mode_for_size (64, MODE_FLOAT, 0))
+  real_to_target (OUT, &(IN), float_mode_for_size (64).require ())
 
 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) \
-  ((OUT) = real_to_target (NULL, &(IN), mode_for_size (32, MODE_FLOAT, 0)))
+  ((OUT) = real_to_target (NULL, &(IN), float_mode_for_size (32).require ()))
 
 /* Real values to IEEE 754 decimal floats.  */
 
 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
 #define REAL_VALUE_TO_TARGET_DECIMAL128(IN, OUT) \
-  real_to_target (OUT, &(IN), mode_for_size (128, MODE_DECIMAL_FLOAT, 0))
+  real_to_target (OUT, &(IN), decimal_float_mode_for_size (128).require ())
 
 #define REAL_VALUE_TO_TARGET_DECIMAL64(IN, OUT) \
-  real_to_target (OUT, &(IN), mode_for_size (64, MODE_DECIMAL_FLOAT, 0))
+  real_to_target (OUT, &(IN), decimal_float_mode_for_size (64).require ())
 
 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
 #define REAL_VALUE_TO_TARGET_DECIMAL32(IN, OUT) \
-  ((OUT) = real_to_target (NULL, &(IN), mode_for_size (32, MODE_DECIMAL_FLOAT, 0)))
+  ((OUT) = real_to_target (NULL, &(IN), \
+			   decimal_float_mode_for_size (32).require ()))
 
 extern REAL_VALUE_TYPE real_value_truncate (format_helper, REAL_VALUE_TYPE);