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-rw-r--r--fpu/softfloat-specialize.h130
-rw-r--r--fpu/softfloat.c130
-rw-r--r--fpu/softfloat.h25
3 files changed, 230 insertions, 55 deletions
diff --git a/fpu/softfloat-specialize.h b/fpu/softfloat-specialize.h
index eb644b2273..2d025bfa36 100644
--- a/fpu/softfloat-specialize.h
+++ b/fpu/softfloat-specialize.h
@@ -57,6 +57,107 @@ 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.
+*----------------------------------------------------------------------------*/
+
+int float16_is_quiet_nan(float16 a_)
+{
+    uint16_t a = float16_val(a_);
+#if SNAN_BIT_IS_ONE
+    return (((a >> 9) & 0x3F) == 0x3E) && (a & 0x1FF);
+#else
+    return ((a & ~0x8000) >= 0x7c80);
+#endif
+}
+
+/*----------------------------------------------------------------------------
+| Returns 1 if the half-precision floating-point value `a' is a signaling
+| NaN; otherwise returns 0.
+*----------------------------------------------------------------------------*/
+
+int float16_is_signaling_nan(float16 a_)
+{
+    uint16_t a = float16_val(a_);
+#if SNAN_BIT_IS_ONE
+    return ((a & ~0x8000) >= 0x7c80);
+#else
+    return (((a >> 9) & 0x3F) == 0x3E) && (a & 0x1FF);
+#endif
+}
+
+/*----------------------------------------------------------------------------
+| Returns a quiet NaN if the half-precision floating point value `a' is a
+| signaling NaN; otherwise returns `a'.
+*----------------------------------------------------------------------------*/
+float16 float16_maybe_silence_nan(float16 a_)
+{
+    if (float16_is_signaling_nan(a_)) {
+#if SNAN_BIT_IS_ONE
+#  if defined(TARGET_MIPS) || defined(TARGET_SH4)
+        return float16_default_nan;
+#  else
+#    error Rules for silencing a signaling NaN are target-specific
+#  endif
+#else
+        uint16_t a = float16_val(a_);
+        a |= (1 << 9);
+        return make_float16(a);
+#endif
+    }
+    return a_;
+}
+
+/*----------------------------------------------------------------------------
+| Returns the result of converting the half-precision floating-point NaN
+| `a' to the canonical NaN format.  If `a' is a signaling NaN, the invalid
+| exception is raised.
+*----------------------------------------------------------------------------*/
+
+static commonNaNT float16ToCommonNaN( float16 a STATUS_PARAM )
+{
+    commonNaNT z;
+
+    if ( float16_is_signaling_nan( a ) ) float_raise( float_flag_invalid STATUS_VAR );
+    z.sign = float16_val(a) >> 15;
+    z.low = 0;
+    z.high = ((bits64) float16_val(a))<<54;
+    return z;
+}
+
+/*----------------------------------------------------------------------------
+| Returns the result of converting the canonical NaN `a' to the half-
+| precision floating-point format.
+*----------------------------------------------------------------------------*/
+
+static float16 commonNaNToFloat16(commonNaNT a STATUS_PARAM)
+{
+    uint16_t mantissa = a.high>>54;
+
+    if (STATUS(default_nan_mode)) {
+        return float16_default_nan;
+    }
+
+    if (mantissa) {
+        return make_float16(((((uint16_t) a.sign) << 15)
+                             | (0x1F << 10) | mantissa));
+    } else {
+        return float16_default_nan;
+    }
+}
+
+/*----------------------------------------------------------------------------
 | The pattern for a default generated single-precision NaN.
 *----------------------------------------------------------------------------*/
 #if defined(TARGET_SPARC)
@@ -144,9 +245,14 @@ static commonNaNT float32ToCommonNaN( float32 a STATUS_PARAM )
 | precision floating-point format.
 *----------------------------------------------------------------------------*/
 
-static float32 commonNaNToFloat32( commonNaNT a )
+static float32 commonNaNToFloat32( commonNaNT a STATUS_PARAM)
 {
     bits32 mantissa = a.high>>41;
+
+    if ( STATUS(default_nan_mode) ) {
+        return float32_default_nan;
+    }
+
     if ( mantissa )
         return make_float32(
             ( ( (bits32) a.sign )<<31 ) | 0x7F800000 | ( a.high>>41 ) );
@@ -398,10 +504,14 @@ static commonNaNT float64ToCommonNaN( float64 a STATUS_PARAM)
 | precision floating-point format.
 *----------------------------------------------------------------------------*/
 
-static float64 commonNaNToFloat64( commonNaNT a )
+static float64 commonNaNToFloat64( commonNaNT a STATUS_PARAM)
 {
     bits64 mantissa = a.high>>12;
 
+    if ( STATUS(default_nan_mode) ) {
+        return float64_default_nan;
+    }
+
     if ( mantissa )
         return make_float64(
               ( ( (bits64) a.sign )<<63 )
@@ -555,10 +665,16 @@ static commonNaNT floatx80ToCommonNaN( floatx80 a STATUS_PARAM)
 | double-precision floating-point format.
 *----------------------------------------------------------------------------*/
 
-static floatx80 commonNaNToFloatx80( commonNaNT a )
+static floatx80 commonNaNToFloatx80( commonNaNT a STATUS_PARAM)
 {
     floatx80 z;
 
+    if ( STATUS(default_nan_mode) ) {
+        z.low = floatx80_default_nan_low;
+        z.high = floatx80_default_nan_high;
+        return z;
+    }
+
     if (a.high)
         z.low = a.high;
     else
@@ -703,10 +819,16 @@ static commonNaNT float128ToCommonNaN( float128 a STATUS_PARAM)
 | precision floating-point format.
 *----------------------------------------------------------------------------*/
 
-static float128 commonNaNToFloat128( commonNaNT a )
+static float128 commonNaNToFloat128( commonNaNT a STATUS_PARAM)
 {
     float128 z;
 
+    if ( STATUS(default_nan_mode) ) {
+        z.low = float128_default_nan_low;
+        z.high = float128_default_nan_high;
+        return z;
+    }
+
     shift128Right( a.high, a.low, 16, &z.high, &z.low );
     z.high |= ( ( (bits64) a.sign )<<63 ) | LIT64( 0x7FFF000000000000 );
     return z;
diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index 17842f43da..30b07e9b44 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -67,6 +67,33 @@ void set_floatx80_rounding_precision(int val STATUS_PARAM)
 #endif
 
 /*----------------------------------------------------------------------------
+| Returns the fraction bits of the half-precision floating-point value `a'.
+*----------------------------------------------------------------------------*/
+
+INLINE uint32_t extractFloat16Frac(float16 a)
+{
+    return float16_val(a) & 0x3ff;
+}
+
+/*----------------------------------------------------------------------------
+| Returns the exponent bits of the half-precision floating-point value `a'.
+*----------------------------------------------------------------------------*/
+
+INLINE int16 extractFloat16Exp(float16 a)
+{
+    return (float16_val(a) >> 10) & 0x1f;
+}
+
+/*----------------------------------------------------------------------------
+| Returns the sign bit of the single-precision floating-point value `a'.
+*----------------------------------------------------------------------------*/
+
+INLINE flag extractFloat16Sign(float16 a)
+{
+    return float16_val(a)>>15;
+}
+
+/*----------------------------------------------------------------------------
 | Takes a 64-bit fixed-point value `absZ' with binary point between bits 6
 | and 7, and returns the properly rounded 32-bit integer corresponding to the
 | input.  If `zSign' is 1, the input is negated before being converted to an
@@ -1534,7 +1561,7 @@ float64 float32_to_float64( float32 a STATUS_PARAM )
     aExp = extractFloat32Exp( a );
     aSign = extractFloat32Sign( a );
     if ( aExp == 0xFF ) {
-        if ( aSig ) return commonNaNToFloat64( float32ToCommonNaN( a STATUS_VAR ));
+        if ( aSig ) return commonNaNToFloat64( float32ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
         return packFloat64( aSign, 0x7FF, 0 );
     }
     if ( aExp == 0 ) {
@@ -1566,7 +1593,7 @@ floatx80 float32_to_floatx80( float32 a STATUS_PARAM )
     aExp = extractFloat32Exp( a );
     aSign = extractFloat32Sign( a );
     if ( aExp == 0xFF ) {
-        if ( aSig ) return commonNaNToFloatx80( float32ToCommonNaN( a STATUS_VAR ) );
+        if ( aSig ) return commonNaNToFloatx80( float32ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
         return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
     }
     if ( aExp == 0 ) {
@@ -1600,7 +1627,7 @@ float128 float32_to_float128( float32 a STATUS_PARAM )
     aExp = extractFloat32Exp( a );
     aSign = extractFloat32Sign( a );
     if ( aExp == 0xFF ) {
-        if ( aSig ) return commonNaNToFloat128( float32ToCommonNaN( a STATUS_VAR ) );
+        if ( aSig ) return commonNaNToFloat128( float32ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
         return packFloat128( aSign, 0x7FFF, 0, 0 );
     }
     if ( aExp == 0 ) {
@@ -2172,21 +2199,21 @@ float32 float32_sqrt( float32 a STATUS_PARAM )
 
 static const float64 float32_exp2_coefficients[15] =
 {
-    make_float64( 0x3ff0000000000000ll ), /*  1 */
-    make_float64( 0x3fe0000000000000ll ), /*  2 */
-    make_float64( 0x3fc5555555555555ll ), /*  3 */
-    make_float64( 0x3fa5555555555555ll ), /*  4 */
-    make_float64( 0x3f81111111111111ll ), /*  5 */
-    make_float64( 0x3f56c16c16c16c17ll ), /*  6 */
-    make_float64( 0x3f2a01a01a01a01all ), /*  7 */
-    make_float64( 0x3efa01a01a01a01all ), /*  8 */
-    make_float64( 0x3ec71de3a556c734ll ), /*  9 */
-    make_float64( 0x3e927e4fb7789f5cll ), /* 10 */
-    make_float64( 0x3e5ae64567f544e4ll ), /* 11 */
-    make_float64( 0x3e21eed8eff8d898ll ), /* 12 */
-    make_float64( 0x3de6124613a86d09ll ), /* 13 */
-    make_float64( 0x3da93974a8c07c9dll ), /* 14 */
-    make_float64( 0x3d6ae7f3e733b81fll ), /* 15 */
+    const_float64( 0x3ff0000000000000ll ), /*  1 */
+    const_float64( 0x3fe0000000000000ll ), /*  2 */
+    const_float64( 0x3fc5555555555555ll ), /*  3 */
+    const_float64( 0x3fa5555555555555ll ), /*  4 */
+    const_float64( 0x3f81111111111111ll ), /*  5 */
+    const_float64( 0x3f56c16c16c16c17ll ), /*  6 */
+    const_float64( 0x3f2a01a01a01a01all ), /*  7 */
+    const_float64( 0x3efa01a01a01a01all ), /*  8 */
+    const_float64( 0x3ec71de3a556c734ll ), /*  9 */
+    const_float64( 0x3e927e4fb7789f5cll ), /* 10 */
+    const_float64( 0x3e5ae64567f544e4ll ), /* 11 */
+    const_float64( 0x3e21eed8eff8d898ll ), /* 12 */
+    const_float64( 0x3de6124613a86d09ll ), /* 13 */
+    const_float64( 0x3da93974a8c07c9dll ), /* 14 */
+    const_float64( 0x3d6ae7f3e733b81fll ), /* 15 */
 };
 
 float32 float32_exp2( float32 a STATUS_PARAM )
@@ -2689,7 +2716,7 @@ float32 float64_to_float32( float64 a STATUS_PARAM )
     aExp = extractFloat64Exp( a );
     aSign = extractFloat64Sign( a );
     if ( aExp == 0x7FF ) {
-        if ( aSig ) return commonNaNToFloat32( float64ToCommonNaN( a STATUS_VAR ) );
+        if ( aSig ) return commonNaNToFloat32( float64ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
         return packFloat32( aSign, 0xFF, 0 );
     }
     shift64RightJamming( aSig, 22, &aSig );
@@ -2713,29 +2740,28 @@ float32 float64_to_float32( float64 a STATUS_PARAM )
 | than the desired result exponent whenever `zSig' is a complete, normalized
 | significand.
 *----------------------------------------------------------------------------*/
-static bits16 packFloat16(flag zSign, int16 zExp, bits16 zSig)
+static float16 packFloat16(flag zSign, int16 zExp, bits16 zSig)
 {
-    return (((bits32)zSign) << 15) + (((bits32)zExp) << 10) + zSig;
+    return make_float16(
+        (((bits32)zSign) << 15) + (((bits32)zExp) << 10) + zSig);
 }
 
 /* Half precision floats come in two formats: standard IEEE and "ARM" format.
    The latter gains extra exponent range by omitting the NaN/Inf encodings.  */
-  
-float32 float16_to_float32( bits16 a, flag ieee STATUS_PARAM )
+
+float32 float16_to_float32(float16 a, flag ieee STATUS_PARAM)
 {
     flag aSign;
     int16 aExp;
     bits32 aSig;
 
-    aSign = a >> 15;
-    aExp = (a >> 10) & 0x1f;
-    aSig = a & 0x3ff;
+    aSign = extractFloat16Sign(a);
+    aExp = extractFloat16Exp(a);
+    aSig = extractFloat16Frac(a);
 
     if (aExp == 0x1f && ieee) {
         if (aSig) {
-            /* Make sure correct exceptions are raised.  */
-            float32ToCommonNaN(a STATUS_VAR);
-            aSig |= 0x200;
+            return commonNaNToFloat32(float16ToCommonNaN(a STATUS_VAR) STATUS_VAR);
         }
         return packFloat32(aSign, 0xff, aSig << 13);
     }
@@ -2753,7 +2779,7 @@ float32 float16_to_float32( bits16 a, flag ieee STATUS_PARAM )
     return packFloat32( aSign, aExp + 0x70, aSig << 13);
 }
 
-bits16 float32_to_float16( float32 a, flag ieee STATUS_PARAM)
+float16 float32_to_float16(float32 a, flag ieee STATUS_PARAM)
 {
     flag aSign;
     int16 aExp;
@@ -2768,24 +2794,30 @@ bits16 float32_to_float16( float32 a, flag ieee STATUS_PARAM)
     aSign = extractFloat32Sign( a );
     if ( aExp == 0xFF ) {
         if (aSig) {
-            /* Make sure correct exceptions are raised.  */
-            float32ToCommonNaN(a STATUS_VAR);
-            aSig |= 0x00400000;
+            /* Input is a NaN */
+            float16 r = commonNaNToFloat16( float32ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
+            if (!ieee) {
+                return packFloat16(aSign, 0, 0);
+            }
+            return r;
+        }
+        /* Infinity */
+        if (!ieee) {
+            float_raise(float_flag_invalid STATUS_VAR);
+            return packFloat16(aSign, 0x1f, 0x3ff);
         }
-        return packFloat16(aSign, 0x1f, aSig >> 13);
+        return packFloat16(aSign, 0x1f, 0);
     }
-    if (aExp == 0 && aSign == 0) {
+    if (aExp == 0 && aSig == 0) {
         return packFloat16(aSign, 0, 0);
     }
     /* Decimal point between bits 22 and 23.  */
     aSig |= 0x00800000;
     aExp -= 0x7f;
     if (aExp < -14) {
-        mask = 0x007fffff;
-        if (aExp < -24) {
-            aExp = -25;
-        } else {
-            mask >>= 24 + aExp;
+        mask = 0x00ffffff;
+        if (aExp >= -24) {
+            mask >>= 25 + aExp;
         }
     } else {
         mask = 0x00001fff;
@@ -2827,7 +2859,7 @@ bits16 float32_to_float16( float32 a, flag ieee STATUS_PARAM)
         }
     } else {
         if (aExp > 16) {
-            float_raise( float_flag_overflow | float_flag_inexact STATUS_VAR);
+            float_raise(float_flag_invalid | float_flag_inexact STATUS_VAR);
             return packFloat16(aSign, 0x1f, 0x3ff);
         }
     }
@@ -2861,7 +2893,7 @@ floatx80 float64_to_floatx80( float64 a STATUS_PARAM )
     aExp = extractFloat64Exp( a );
     aSign = extractFloat64Sign( a );
     if ( aExp == 0x7FF ) {
-        if ( aSig ) return commonNaNToFloatx80( float64ToCommonNaN( a STATUS_VAR ) );
+        if ( aSig ) return commonNaNToFloatx80( float64ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
         return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
     }
     if ( aExp == 0 ) {
@@ -2896,7 +2928,7 @@ float128 float64_to_float128( float64 a STATUS_PARAM )
     aExp = extractFloat64Exp( a );
     aSign = extractFloat64Sign( a );
     if ( aExp == 0x7FF ) {
-        if ( aSig ) return commonNaNToFloat128( float64ToCommonNaN( a STATUS_VAR ) );
+        if ( aSig ) return commonNaNToFloat128( float64ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
         return packFloat128( aSign, 0x7FFF, 0, 0 );
     }
     if ( aExp == 0 ) {
@@ -3843,7 +3875,7 @@ float32 floatx80_to_float32( floatx80 a STATUS_PARAM )
     aSign = extractFloatx80Sign( a );
     if ( aExp == 0x7FFF ) {
         if ( (bits64) ( aSig<<1 ) ) {
-            return commonNaNToFloat32( floatx80ToCommonNaN( a STATUS_VAR ) );
+            return commonNaNToFloat32( floatx80ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
         }
         return packFloat32( aSign, 0xFF, 0 );
     }
@@ -3871,7 +3903,7 @@ float64 floatx80_to_float64( floatx80 a STATUS_PARAM )
     aSign = extractFloatx80Sign( a );
     if ( aExp == 0x7FFF ) {
         if ( (bits64) ( aSig<<1 ) ) {
-            return commonNaNToFloat64( floatx80ToCommonNaN( a STATUS_VAR ) );
+            return commonNaNToFloat64( floatx80ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
         }
         return packFloat64( aSign, 0x7FF, 0 );
     }
@@ -3900,7 +3932,7 @@ float128 floatx80_to_float128( floatx80 a STATUS_PARAM )
     aExp = extractFloatx80Exp( a );
     aSign = extractFloatx80Sign( a );
     if ( ( aExp == 0x7FFF ) && (bits64) ( aSig<<1 ) ) {
-        return commonNaNToFloat128( floatx80ToCommonNaN( a STATUS_VAR ) );
+        return commonNaNToFloat128( floatx80ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
     }
     shift128Right( aSig<<1, 0, 16, &zSig0, &zSig1 );
     return packFloat128( aSign, aExp, zSig0, zSig1 );
@@ -4863,7 +4895,7 @@ float32 float128_to_float32( float128 a STATUS_PARAM )
     aSign = extractFloat128Sign( a );
     if ( aExp == 0x7FFF ) {
         if ( aSig0 | aSig1 ) {
-            return commonNaNToFloat32( float128ToCommonNaN( a STATUS_VAR ) );
+            return commonNaNToFloat32( float128ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
         }
         return packFloat32( aSign, 0xFF, 0 );
     }
@@ -4897,7 +4929,7 @@ float64 float128_to_float64( float128 a STATUS_PARAM )
     aSign = extractFloat128Sign( a );
     if ( aExp == 0x7FFF ) {
         if ( aSig0 | aSig1 ) {
-            return commonNaNToFloat64( float128ToCommonNaN( a STATUS_VAR ) );
+            return commonNaNToFloat64( float128ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
         }
         return packFloat64( aSign, 0x7FF, 0 );
     }
@@ -4932,7 +4964,7 @@ floatx80 float128_to_floatx80( float128 a STATUS_PARAM )
     aSign = extractFloat128Sign( a );
     if ( aExp == 0x7FFF ) {
         if ( aSig0 | aSig1 ) {
-            return commonNaNToFloatx80( float128ToCommonNaN( a STATUS_VAR ) );
+            return commonNaNToFloatx80( float128ToCommonNaN( a STATUS_VAR ) STATUS_VAR );
         }
         return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
     }
diff --git a/fpu/softfloat.h b/fpu/softfloat.h
index 4a5345ceca..e57ee1efb0 100644
--- a/fpu/softfloat.h
+++ b/fpu/softfloat.h
@@ -120,23 +120,37 @@ enum {
 //#define USE_SOFTFLOAT_STRUCT_TYPES
 #ifdef USE_SOFTFLOAT_STRUCT_TYPES
 typedef struct {
+    uint16_t v;
+} float16;
+#define float16_val(x) (((float16)(x)).v)
+#define make_float16(x) __extension__ ({ float16 f16_val = {x}; f16_val; })
+#define const_float16(x) { x }
+typedef struct {
     uint32_t v;
 } float32;
 /* The cast ensures an error if the wrong type is passed.  */
 #define float32_val(x) (((float32)(x)).v)
 #define make_float32(x) __extension__ ({ float32 f32_val = {x}; f32_val; })
+#define const_float32(x) { x }
 typedef struct {
     uint64_t v;
 } float64;
 #define float64_val(x) (((float64)(x)).v)
 #define make_float64(x) __extension__ ({ float64 f64_val = {x}; f64_val; })
+#define const_float64(x) { x }
 #else
+typedef uint16_t float16;
 typedef uint32_t float32;
 typedef uint64_t float64;
+#define float16_val(x) (x)
 #define float32_val(x) (x)
 #define float64_val(x) (x)
+#define make_float16(x) (x)
 #define make_float32(x) (x)
 #define make_float64(x) (x)
+#define const_float16(x) (x)
+#define const_float32(x) (x)
+#define const_float64(x) (x)
 #endif
 #ifdef FLOATX80
 typedef struct {
@@ -253,8 +267,15 @@ float128 int64_to_float128( int64_t STATUS_PARAM );
 /*----------------------------------------------------------------------------
 | Software half-precision conversion routines.
 *----------------------------------------------------------------------------*/
-bits16 float32_to_float16( float32, flag STATUS_PARAM );
-float32 float16_to_float32( bits16, flag STATUS_PARAM );
+float16 float32_to_float16( float32, flag STATUS_PARAM );
+float32 float16_to_float32( float16, flag STATUS_PARAM );
+
+/*----------------------------------------------------------------------------
+| Software half-precision operations.
+*----------------------------------------------------------------------------*/
+int float16_is_quiet_nan( float16 );
+int float16_is_signaling_nan( float16 );
+float16 float16_maybe_silence_nan( float16 );
 
 /*----------------------------------------------------------------------------
 | Software IEC/IEEE single-precision conversion routines.