fpu/softfloat: Split floatXX_silence_nan from floatXX_maybe_silence_nan

The new function assumes that the input is an SNaN and
does not double-check.

Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

2 files changed, 123 insertions, 56 deletions

diff --git a/fpu/softfloat-specialize.h b/fpu/softfloat-specialize.h
index 58b05718c8..4fc9ea4ac0 100644
--- a/fpu/softfloat-specialize.h
+++ b/fpu/softfloat-specialize.h
@@ -272,21 +272,34 @@ int float16_is_signaling_nan(float16 a_, float_status *status)
 }
 
 /*----------------------------------------------------------------------------
+| Returns a quiet NaN from a signalling NaN for the half-precision
+| floating point value `a'.
+*----------------------------------------------------------------------------*/
+
+float16 float16_silence_nan(float16 a, float_status *status)
+{
+#ifdef NO_SIGNALING_NANS
+    g_assert_not_reached();
+#else
+    if (status->snan_bit_is_one) {
+        return float16_default_nan(status);
+    } else {
+        return a | (1 << 9);
+    }
+#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_, float_status *status)
+
+float16 float16_maybe_silence_nan(float16 a, float_status *status)
 {
-    if (float16_is_signaling_nan(a_, status)) {
-        if (status->snan_bit_is_one) {
-            return float16_default_nan(status);
-        } else {
-            uint16_t a = float16_val(a_);
-            a |= (1 << 9);
-            return make_float16(a);
-        }
+    if (float16_is_signaling_nan(a, status)) {
+        return float16_silence_nan(a, status);
     }
-    return a_;
+    return a;
 }
 
 /*----------------------------------------------------------------------------
@@ -368,29 +381,39 @@ int float32_is_signaling_nan(float32 a_, float_status *status)
 }
 
 /*----------------------------------------------------------------------------
-| Returns a quiet NaN if the single-precision floating point value `a' is a
-| signaling NaN; otherwise returns `a'.
+| Returns a quiet NaN from a signalling NaN for the single-precision
+| floating point value `a'.
 *----------------------------------------------------------------------------*/
 
-float32 float32_maybe_silence_nan(float32 a_, float_status *status)
+float32 float32_silence_nan(float32 a, float_status *status)
 {
-    if (float32_is_signaling_nan(a_, status)) {
-        if (status->snan_bit_is_one) {
-#ifdef TARGET_HPPA
-            uint32_t a = float32_val(a_);
-            a &= ~0x00400000;
-            a |=  0x00200000;
-            return make_float32(a);
+#ifdef NO_SIGNALING_NANS
+    g_assert_not_reached();
 #else
-            return float32_default_nan(status);
+    if (status->snan_bit_is_one) {
+# ifdef TARGET_HPPA
+        a &= ~0x00400000;
+        a |=  0x00200000;
+        return a;
+# else
+        return float32_default_nan(status);
+# endif
+    } else {
+        return a | (1 << 22);
+    }
 #endif
-        } else {
-            uint32_t a = float32_val(a_);
-            a |= (1 << 22);
-            return make_float32(a);
-        }
+}
+/*----------------------------------------------------------------------------
+| Returns a quiet NaN if the single-precision floating point value `a' is a
+| signaling NaN; otherwise returns `a'.
+*----------------------------------------------------------------------------*/
+
+float32 float32_maybe_silence_nan(float32 a, float_status *status)
+{
+    if (float32_is_signaling_nan(a, status)) {
+        return float32_silence_nan(a, status);
     }
-    return a_;
+    return a;
 }
 
 /*----------------------------------------------------------------------------
@@ -777,29 +800,40 @@ int float64_is_signaling_nan(float64 a_, float_status *status)
 }
 
 /*----------------------------------------------------------------------------
-| Returns a quiet NaN if the double-precision floating point value `a' is a
-| signaling NaN; otherwise returns `a'.
+| Returns a quiet NaN from a signalling NaN for the double-precision
+| floating point value `a'.
 *----------------------------------------------------------------------------*/
 
-float64 float64_maybe_silence_nan(float64 a_, float_status *status)
+float64 float64_silence_nan(float64 a, float_status *status)
 {
-    if (float64_is_signaling_nan(a_, status)) {
-        if (status->snan_bit_is_one) {
-#ifdef TARGET_HPPA
-            uint64_t a = float64_val(a_);
-            a &= ~0x0008000000000000ULL;
-            a |=  0x0004000000000000ULL;
-            return make_float64(a);
+#ifdef NO_SIGNALING_NANS
+    g_assert_not_reached();
 #else
-            return float64_default_nan(status);
+    if (status->snan_bit_is_one) {
+# ifdef TARGET_HPPA
+        a &= ~0x0008000000000000ULL;
+        a |=  0x0004000000000000ULL;
+        return a;
+# else
+        return float64_default_nan(status);
+# endif
+    } else {
+        return a | LIT64(0x0008000000000000);
+    }
 #endif
-        } else {
-            uint64_t a = float64_val(a_);
-            a |= LIT64(0x0008000000000000);
-            return make_float64(a);
-        }
+}
+
+/*----------------------------------------------------------------------------
+| Returns a quiet NaN if the double-precision floating point value `a' is a
+| signaling NaN; otherwise returns `a'.
+*----------------------------------------------------------------------------*/
+
+float64 float64_maybe_silence_nan(float64 a, float_status *status)
+{
+    if (float64_is_signaling_nan(a, status)) {
+        return float64_silence_nan(a, status);
     }
-    return a_;
+    return a;
 }
 
 /*----------------------------------------------------------------------------
@@ -938,6 +972,25 @@ int floatx80_is_signaling_nan(floatx80 a, float_status *status)
 }
 
 /*----------------------------------------------------------------------------
+| Returns a quiet NaN from a signalling NaN for the extended double-precision
+| floating point value `a'.
+*----------------------------------------------------------------------------*/
+
+floatx80 floatx80_silence_nan(floatx80 a, float_status *status)
+{
+#ifdef NO_SIGNALING_NANS
+    g_assert_not_reached();
+#else
+    if (status->snan_bit_is_one) {
+        return floatx80_default_nan(status);
+    } else {
+        a.low |= LIT64(0xC000000000000000);
+        return a;
+    }
+#endif
+}
+
+/*----------------------------------------------------------------------------
 | Returns a quiet NaN if the extended double-precision floating point value
 | `a' is a signaling NaN; otherwise returns `a'.
 *----------------------------------------------------------------------------*/
@@ -945,12 +998,7 @@ int floatx80_is_signaling_nan(floatx80 a, float_status *status)
 floatx80 floatx80_maybe_silence_nan(floatx80 a, float_status *status)
 {
     if (floatx80_is_signaling_nan(a, status)) {
-        if (status->snan_bit_is_one) {
-            a = floatx80_default_nan(status);
-        } else {
-            a.low |= LIT64(0xC000000000000000);
-            return a;
-        }
+        return floatx80_silence_nan(a, status);
     }
     return a;
 }
@@ -1085,6 +1133,25 @@ int float128_is_signaling_nan(float128 a, float_status *status)
 }
 
 /*----------------------------------------------------------------------------
+| Returns a quiet NaN from a signalling NaN for the quadruple-precision
+| floating point value `a'.
+*----------------------------------------------------------------------------*/
+
+float128 float128_silence_nan(float128 a, float_status *status)
+{
+#ifdef NO_SIGNALING_NANS
+    g_assert_not_reached();
+#else
+    if (status->snan_bit_is_one) {
+        return float128_default_nan(status);
+    } else {
+        a.high |= LIT64(0x0000800000000000);
+        return a;
+    }
+#endif
+}
+
+/*----------------------------------------------------------------------------
 | Returns a quiet NaN if the quadruple-precision floating point value `a' is
 | a signaling NaN; otherwise returns `a'.
 *----------------------------------------------------------------------------*/
@@ -1092,12 +1159,7 @@ int float128_is_signaling_nan(float128 a, float_status *status)
 float128 float128_maybe_silence_nan(float128 a, float_status *status)
 {
     if (float128_is_signaling_nan(a, status)) {
-        if (status->snan_bit_is_one) {
-            a = float128_default_nan(status);
-        } else {
-            a.high |= LIT64(0x0000800000000000);
-            return a;
-        }
+        return float128_silence_nan(a, status);
     }
     return a;
 }
diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h
index 36626a501b..43962dc3f5 100644
--- a/include/fpu/softfloat.h
+++ b/include/fpu/softfloat.h
@@ -257,6 +257,7 @@ int float16_compare_quiet(float16, float16, float_status *status);
 
 int float16_is_quiet_nan(float16, float_status *status);
 int float16_is_signaling_nan(float16, float_status *status);
+float16 float16_silence_nan(float16, float_status *status);
 float16 float16_maybe_silence_nan(float16, float_status *status);
 
 static inline int float16_is_any_nan(float16 a)
@@ -368,6 +369,7 @@ float32 float32_minnummag(float32, float32, float_status *status);
 float32 float32_maxnummag(float32, float32, float_status *status);
 int float32_is_quiet_nan(float32, float_status *status);
 int float32_is_signaling_nan(float32, float_status *status);
+float32 float32_silence_nan(float32, float_status *status);
 float32 float32_maybe_silence_nan(float32, float_status *status);
 float32 float32_scalbn(float32, int, float_status *status);
 
@@ -497,6 +499,7 @@ float64 float64_minnummag(float64, float64, float_status *status);
 float64 float64_maxnummag(float64, float64, float_status *status);
 int float64_is_quiet_nan(float64 a, float_status *status);
 int float64_is_signaling_nan(float64, float_status *status);
+float64 float64_silence_nan(float64, float_status *status);
 float64 float64_maybe_silence_nan(float64, float_status *status);
 float64 float64_scalbn(float64, int, float_status *status);
 
@@ -600,6 +603,7 @@ int floatx80_compare(floatx80, floatx80, float_status *status);
 int floatx80_compare_quiet(floatx80, floatx80, float_status *status);
 int floatx80_is_quiet_nan(floatx80, float_status *status);
 int floatx80_is_signaling_nan(floatx80, float_status *status);
+floatx80 floatx80_silence_nan(floatx80, float_status *status);
 floatx80 floatx80_maybe_silence_nan(floatx80, float_status *status);
 floatx80 floatx80_scalbn(floatx80, int, float_status *status);
 
@@ -811,6 +815,7 @@ int float128_compare(float128, float128, float_status *status);
 int float128_compare_quiet(float128, float128, float_status *status);
 int float128_is_quiet_nan(float128, float_status *status);
 int float128_is_signaling_nan(float128, float_status *status);
+float128 float128_silence_nan(float128, float_status *status);
 float128 float128_maybe_silence_nan(float128, float_status *status);
 float128 float128_scalbn(float128, int, float_status *status);