Patchwork [1/2] softfloat: export float32_nan and float32_infinity.

login
register
mail settings
Submitter Christophe LYON
Date Feb. 16, 2011, 2:51 p.m.
Message ID <1297867883-18390-2-git-send-email-christophe.lyon@st.com>
Download mbox | patch
Permalink /patch/83369/
State New
Headers show

Comments

Christophe LYON - Feb. 16, 2011, 2:51 p.m.
From: Christophe Lyon <christophe.lyon@st.com>

These two special values are needed to implement some helper
functions, which return these values in some cases.

This patch also moves the definitions of default_nan for 16, 64, x80
and 128 bits floats for consistency with float32.

Signed-off-by: Christophe Lyon <christophe.lyon@st.com>
---
 fpu/softfloat-specialize.h |   68 ------------------------------------------
 fpu/softfloat.h            |   71 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+), 68 deletions(-)
Peter Maydell - Feb. 16, 2011, 4:54 p.m.
On 16 February 2011 14:51,  <christophe.lyon@st.com> wrote:
> From: Christophe Lyon <christophe.lyon@st.com>
>
> These two special values are needed to implement some helper
> functions, which return these values in some cases.
>
> This patch also moves the definitions of default_nan for 16, 64, x80
> and 128 bits floats for consistency with float32.

Your other patch only uses float32_infinity, not float32_nan
or float32_default_nan, which renders a lot of this patch moot
at the moment.

> +#define float32_nan float32_default_nan

If we do need to expose NaN, we should just have callers
use float32_default_nan, there's no need for this extra
#define.

-- PMM
Christophe LYON - Feb. 16, 2011, 4:58 p.m.
On 16.02.2011 17:54, Peter Maydell wrote:
> On 16 February 2011 14:51,  <christophe.lyon@st.com> wrote:
>> From: Christophe Lyon <christophe.lyon@st.com>
>>
>> These two special values are needed to implement some helper
>> functions, which return these values in some cases.
>>
>> This patch also moves the definitions of default_nan for 16, 64, x80
>> and 128 bits floats for consistency with float32.
> 
> Your other patch only uses float32_infinity, not float32_nan
> or float32_default_nan, which renders a lot of this patch moot
> at the moment.

Indeed, I have another patch for vrsqrte which does need float32_nan.

>> +#define float32_nan float32_default_nan
> 
> If we do need to expose NaN, we should just have callers
> use float32_default_nan, there's no need for this extra
> #define.
>

Patch

diff --git a/fpu/softfloat-specialize.h b/fpu/softfloat-specialize.h
index 2d025bf..adc5ada 100644
--- a/fpu/softfloat-specialize.h
+++ b/fpu/softfloat-specialize.h
@@ -30,12 +30,6 @@  these four paragraphs for those parts of this code that are retained.
 
 =============================================================================*/
 
-#if defined(TARGET_MIPS) || defined(TARGET_SH4)
-#define SNAN_BIT_IS_ONE		1
-#else
-#define SNAN_BIT_IS_ONE		0
-#endif
-
 /*----------------------------------------------------------------------------
 | Raises the exceptions specified by `flags'.  Floating-point traps can be
 | defined here if desired.  It is currently not possible for such a trap
@@ -57,17 +51,6 @@  typedef struct {
 } commonNaNT;
 
 /*----------------------------------------------------------------------------
-| The pattern for a default generated half-precision NaN.
-*----------------------------------------------------------------------------*/
-#if defined(TARGET_ARM)
-#define float16_default_nan make_float16(0x7E00)
-#elif SNAN_BIT_IS_ONE
-#define float16_default_nan make_float16(0x7DFF)
-#else
-#define float16_default_nan make_float16(0xFE00)
-#endif
-
-/*----------------------------------------------------------------------------
 | Returns 1 if the half-precision floating-point value `a' is a quiet
 | NaN; otherwise returns 0.
 *----------------------------------------------------------------------------*/
@@ -158,19 +141,6 @@  static float16 commonNaNToFloat16(commonNaNT a STATUS_PARAM)
 }
 
 /*----------------------------------------------------------------------------
-| The pattern for a default generated single-precision NaN.
-*----------------------------------------------------------------------------*/
-#if defined(TARGET_SPARC)
-#define float32_default_nan make_float32(0x7FFFFFFF)
-#elif defined(TARGET_PPC) || defined(TARGET_ARM) || defined(TARGET_ALPHA)
-#define float32_default_nan make_float32(0x7FC00000)
-#elif SNAN_BIT_IS_ONE
-#define float32_default_nan make_float32(0x7FBFFFFF)
-#else
-#define float32_default_nan make_float32(0xFFC00000)
-#endif
-
-/*----------------------------------------------------------------------------
 | Returns 1 if the single-precision floating-point value `a' is a quiet
 | NaN; otherwise returns 0.
 *----------------------------------------------------------------------------*/
@@ -413,19 +383,6 @@  static float32 propagateFloat32NaN( float32 a, float32 b STATUS_PARAM)
 }
 
 /*----------------------------------------------------------------------------
-| The pattern for a default generated double-precision NaN.
-*----------------------------------------------------------------------------*/
-#if defined(TARGET_SPARC)
-#define float64_default_nan make_float64(LIT64( 0x7FFFFFFFFFFFFFFF ))
-#elif defined(TARGET_PPC) || defined(TARGET_ARM) || defined(TARGET_ALPHA)
-#define float64_default_nan make_float64(LIT64( 0x7FF8000000000000 ))
-#elif SNAN_BIT_IS_ONE
-#define float64_default_nan make_float64(LIT64( 0x7FF7FFFFFFFFFFFF ))
-#else
-#define float64_default_nan make_float64(LIT64( 0xFFF8000000000000 ))
-#endif
-
-/*----------------------------------------------------------------------------
 | Returns 1 if the double-precision floating-point value `a' is a quiet
 | NaN; otherwise returns 0.
 *----------------------------------------------------------------------------*/
@@ -564,19 +521,6 @@  static float64 propagateFloat64NaN( float64 a, float64 b STATUS_PARAM)
 #ifdef FLOATX80
 
 /*----------------------------------------------------------------------------
-| The pattern for a default generated extended double-precision NaN.  The
-| `high' and `low' values hold the most- and least-significant bits,
-| respectively.
-*----------------------------------------------------------------------------*/
-#if SNAN_BIT_IS_ONE
-#define floatx80_default_nan_high 0x7FFF
-#define floatx80_default_nan_low  LIT64( 0xBFFFFFFFFFFFFFFF )
-#else
-#define floatx80_default_nan_high 0xFFFF
-#define floatx80_default_nan_low  LIT64( 0xC000000000000000 )
-#endif
-
-/*----------------------------------------------------------------------------
 | Returns 1 if the extended double-precision floating-point value `a' is a
 | quiet NaN; otherwise returns 0. This slightly differs from the same
 | function for other types as floatx80 has an explicit bit.
@@ -728,18 +672,6 @@  static floatx80 propagateFloatx80NaN( floatx80 a, floatx80 b STATUS_PARAM)
 #ifdef FLOAT128
 
 /*----------------------------------------------------------------------------
-| The pattern for a default generated quadruple-precision NaN.  The `high' and
-| `low' values hold the most- and least-significant bits, respectively.
-*----------------------------------------------------------------------------*/
-#if SNAN_BIT_IS_ONE
-#define float128_default_nan_high LIT64( 0x7FFF7FFFFFFFFFFF )
-#define float128_default_nan_low  LIT64( 0xFFFFFFFFFFFFFFFF )
-#else
-#define float128_default_nan_high LIT64( 0xFFFF800000000000 )
-#define float128_default_nan_low  LIT64( 0x0000000000000000 )
-#endif
-
-/*----------------------------------------------------------------------------
 | Returns 1 if the quadruple-precision floating-point value `a' is a quiet
 | NaN; otherwise returns 0.
 *----------------------------------------------------------------------------*/
diff --git a/fpu/softfloat.h b/fpu/softfloat.h
index e57ee1e..7bb77d5 100644
--- a/fpu/softfloat.h
+++ b/fpu/softfloat.h
@@ -77,6 +77,12 @@  typedef int64_t sbits64;
 #define LIT64( a ) a##LL
 #define INLINE static inline
 
+#if defined(TARGET_MIPS) || defined(TARGET_SH4)
+#define SNAN_BIT_IS_ONE		1
+#else
+#define SNAN_BIT_IS_ONE		0
+#endif
+
 /*----------------------------------------------------------------------------
 | The macro `FLOATX80' must be defined to enable the extended double-precision
 | floating-point format `floatx80'.  If this macro is not defined, the
@@ -278,6 +284,17 @@  int float16_is_signaling_nan( float16 );
 float16 float16_maybe_silence_nan( float16 );
 
 /*----------------------------------------------------------------------------
+| The pattern for a default generated half-precision NaN.
+*----------------------------------------------------------------------------*/
+#if defined(TARGET_ARM)
+#define float16_default_nan make_float16(0x7E00)
+#elif SNAN_BIT_IS_ONE
+#define float16_default_nan make_float16(0x7DFF)
+#else
+#define float16_default_nan make_float16(0xFE00)
+#endif
+
+/*----------------------------------------------------------------------------
 | Software IEC/IEEE single-precision conversion routines.
 *----------------------------------------------------------------------------*/
 int float32_to_int16_round_to_zero( float32 STATUS_PARAM );
@@ -365,6 +382,22 @@  INLINE int float32_is_zero_or_denormal(float32 a)
 #define float32_zero make_float32(0)
 #define float32_one make_float32(0x3f800000)
 #define float32_ln2 make_float32(0x3f317218)
+#define float32_infinity make_float32(0x7f800000)
+#define float32_nan float32_default_nan
+
+
+/*----------------------------------------------------------------------------
+| The pattern for a default generated single-precision NaN.
+*----------------------------------------------------------------------------*/
+#if defined(TARGET_SPARC)
+#define float32_default_nan make_float32(0x7FFFFFFF)
+#elif defined(TARGET_PPC) || defined(TARGET_ARM) || defined(TARGET_ALPHA)
+#define float32_default_nan make_float32(0x7FC00000)
+#elif SNAN_BIT_IS_ONE
+#define float32_default_nan make_float32(0x7FBFFFFF)
+#else
+#define float32_default_nan make_float32(0xFFC00000)
+#endif
 
 /*----------------------------------------------------------------------------
 | Software IEC/IEEE double-precision conversion routines.
@@ -452,6 +485,19 @@  INLINE int float64_is_any_nan(float64 a)
 #define float64_one make_float64(0x3ff0000000000000LL)
 #define float64_ln2 make_float64(0x3fe62e42fefa39efLL)
 
+/*----------------------------------------------------------------------------
+| The pattern for a default generated double-precision NaN.
+*----------------------------------------------------------------------------*/
+#if defined(TARGET_SPARC)
+#define float64_default_nan make_float64(LIT64( 0x7FFFFFFFFFFFFFFF ))
+#elif defined(TARGET_PPC) || defined(TARGET_ARM) || defined(TARGET_ALPHA)
+#define float64_default_nan make_float64(LIT64( 0x7FF8000000000000 ))
+#elif SNAN_BIT_IS_ONE
+#define float64_default_nan make_float64(LIT64( 0x7FF7FFFFFFFFFFFF ))
+#else
+#define float64_default_nan make_float64(LIT64( 0xFFF8000000000000 ))
+#endif
+
 #ifdef FLOATX80
 
 /*----------------------------------------------------------------------------
@@ -520,6 +566,19 @@  INLINE int floatx80_is_any_nan(floatx80 a)
     return ((a.high & 0x7fff) == 0x7fff) && (a.low<<1);
 }
 
+/*----------------------------------------------------------------------------
+| The pattern for a default generated extended double-precision NaN.  The
+| `high' and `low' values hold the most- and least-significant bits,
+| respectively.
+*----------------------------------------------------------------------------*/
+#if SNAN_BIT_IS_ONE
+#define floatx80_default_nan_high 0x7FFF
+#define floatx80_default_nan_low  LIT64( 0xBFFFFFFFFFFFFFFF )
+#else
+#define floatx80_default_nan_high 0xFFFF
+#define floatx80_default_nan_low  LIT64( 0xC000000000000000 )
+#endif
+
 #endif
 
 #ifdef FLOAT128
@@ -593,6 +652,18 @@  INLINE int float128_is_any_nan(float128 a)
         ((a.low != 0) || ((a.high & 0xffffffffffffLL) != 0));
 }
 
+/*----------------------------------------------------------------------------
+| The pattern for a default generated quadruple-precision NaN.  The `high' and
+| `low' values hold the most- and least-significant bits, respectively.
+*----------------------------------------------------------------------------*/
+#if SNAN_BIT_IS_ONE
+#define float128_default_nan_high LIT64( 0x7FFF7FFFFFFFFFFF )
+#define float128_default_nan_low  LIT64( 0xFFFFFFFFFFFFFFFF )
+#else
+#define float128_default_nan_high LIT64( 0xFFFF800000000000 )
+#define float128_default_nan_low  LIT64( 0x0000000000000000 )
+#endif
+
 #endif
 
 #else /* CONFIG_SOFTFLOAT */