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softfloat: make NO_SIGNALING_NANS runtime property

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target/xtensa, the only user of NO_SIGNALING_NANS macro has FPU
implementations with and without the corresponding property. With
NO_SIGNALING_NANS being a macro they cannot be a part of the same QEMU
executable.
Replace macro with new property in float_status to allow cores with
different FPU implementations coexist.

Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: "Alex Bennée" <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This commit is contained in:
Max Filippov 2020-06-30 19:35:49 -07:00
parent a7d479ee51
commit cc43c69251
3 changed files with 129 additions and 113 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

230
fpu/softfloat-specialize.c.inc
View File

@ -79,12 +79,18 @@ this code that are retained.
* version 2 or later. See the COPYING file in the top-level directory.
*/
/* Define for architectures which deviate from IEEE in not supporting
/*
* Define whether architecture deviates from IEEE in not supporting
* signaling NaNs (so all NaNs are treated as quiet).
*/
static inline bool no_signaling_nans(float_status *status)
{
#if defined(TARGET_XTENSA)
#define NO_SIGNALING_NANS 1
return status->no_signaling_nans;
#else
return false;
#endif
}
/* Define how the architecture discriminates signaling NaNs.
* This done with the most significant bit of the fraction.
@ -111,12 +117,12 @@ static inline bool snan_bit_is_one(float_status *status)
static bool parts_is_snan_frac(uint64_t frac, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return false;
#else
bool msb = extract64(frac, DECOMPOSED_BINARY_POINT - 1, 1);
return msb == snan_bit_is_one(status);
#endif
if (no_signaling_nans(status)) {
return false;
} else {
bool msb = extract64(frac, DECOMPOSED_BINARY_POINT - 1, 1);
return msb == snan_bit_is_one(status);
}
}
/*----------------------------------------------------------------------------
@ -170,9 +176,8 @@ static FloatParts parts_default_nan(float_status *status)
static FloatParts parts_silence_nan(FloatParts a, float_status *status)
{
#ifdef NO_SIGNALING_NANS
g_assert_not_reached();
#elif defined(TARGET_HPPA)
g_assert(!no_signaling_nans(status));
#if defined(TARGET_HPPA)
a.frac &= ~(1ULL << (DECOMPOSED_BINARY_POINT - 1));
a.frac |= 1ULL << (DECOMPOSED_BINARY_POINT - 2);
#else
@ -247,16 +252,17 @@ typedef struct {
bool float16_is_quiet_nan(float16 a_, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return float16_is_any_nan(a_);
#else
uint16_t a = float16_val(a_);
if (snan_bit_is_one(status)) {
return (((a >> 9) & 0x3F) == 0x3E) && (a & 0x1FF);
if (no_signaling_nans(status)) {
return float16_is_any_nan(a_);
} else {
return ((a >> 9) & 0x3F) == 0x3F;
uint16_t a = float16_val(a_);
if (snan_bit_is_one(status)) {
return (((a >> 9) & 0x3F) == 0x3E) && (a & 0x1FF);
} else {
return ((a >> 9) & 0x3F) == 0x3F;
}
}
#endif
}
/*----------------------------------------------------------------------------
@ -266,16 +272,16 @@ bool float16_is_quiet_nan(float16 a_, float_status *status)
bool float16_is_signaling_nan(float16 a_, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return 0;
#else
uint16_t a = float16_val(a_);
if (snan_bit_is_one(status)) {
return ((a >> 9) & 0x3F) == 0x3F;
if (no_signaling_nans(status)) {
return 0;
} else {
return (((a >> 9) & 0x3F) == 0x3E) && (a & 0x1FF);
uint16_t a = float16_val(a_);
if (snan_bit_is_one(status)) {
return ((a >> 9) & 0x3F) == 0x3F;
} else {
return (((a >> 9) & 0x3F) == 0x3E) && (a & 0x1FF);
}
}
#endif
}
/*----------------------------------------------------------------------------
@ -285,16 +291,16 @@ bool float16_is_signaling_nan(float16 a_, float_status *status)
bool float32_is_quiet_nan(float32 a_, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return float32_is_any_nan(a_);
#else
uint32_t a = float32_val(a_);
if (snan_bit_is_one(status)) {
return (((a >> 22) & 0x1FF) == 0x1FE) && (a & 0x003FFFFF);
if (no_signaling_nans(status)) {
return float32_is_any_nan(a_);
} else {
return ((uint32_t)(a << 1) >= 0xFF800000);
uint32_t a = float32_val(a_);
if (snan_bit_is_one(status)) {
return (((a >> 22) & 0x1FF) == 0x1FE) && (a & 0x003FFFFF);
} else {
return ((uint32_t)(a << 1) >= 0xFF800000);
}
}
#endif
}
/*----------------------------------------------------------------------------
@ -304,16 +310,16 @@ bool float32_is_quiet_nan(float32 a_, float_status *status)
bool float32_is_signaling_nan(float32 a_, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return 0;
#else
uint32_t a = float32_val(a_);
if (snan_bit_is_one(status)) {
return ((uint32_t)(a << 1) >= 0xFF800000);
if (no_signaling_nans(status)) {
return 0;
} else {
return (((a >> 22) & 0x1FF) == 0x1FE) && (a & 0x003FFFFF);
uint32_t a = float32_val(a_);
if (snan_bit_is_one(status)) {
return ((uint32_t)(a << 1) >= 0xFF800000);
} else {
return (((a >> 22) & 0x1FF) == 0x1FE) && (a & 0x003FFFFF);
}
}
#endif
}
/*----------------------------------------------------------------------------
@ -639,17 +645,17 @@ static float32 propagateFloat32NaN(float32 a, float32 b, float_status *status)
bool float64_is_quiet_nan(float64 a_, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return float64_is_any_nan(a_);
#else
uint64_t a = float64_val(a_);
if (snan_bit_is_one(status)) {
return (((a >> 51) & 0xFFF) == 0xFFE)
&& (a & 0x0007FFFFFFFFFFFFULL);
if (no_signaling_nans(status)) {
return float64_is_any_nan(a_);
} else {
return ((a << 1) >= 0xFFF0000000000000ULL);
uint64_t a = float64_val(a_);
if (snan_bit_is_one(status)) {
return (((a >> 51) & 0xFFF) == 0xFFE)
&& (a & 0x0007FFFFFFFFFFFFULL);
} else {
return ((a << 1) >= 0xFFF0000000000000ULL);
}
}
#endif
}
/*----------------------------------------------------------------------------
@ -659,17 +665,17 @@ bool float64_is_quiet_nan(float64 a_, float_status *status)
bool float64_is_signaling_nan(float64 a_, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return 0;
#else
uint64_t a = float64_val(a_);
if (snan_bit_is_one(status)) {
return ((a << 1) >= 0xFFF0000000000000ULL);
if (no_signaling_nans(status)) {
return 0;
} else {
return (((a >> 51) & 0xFFF) == 0xFFE)
&& (a & UINT64_C(0x0007FFFFFFFFFFFF));
uint64_t a = float64_val(a_);
if (snan_bit_is_one(status)) {
return ((a << 1) >= 0xFFF0000000000000ULL);
} else {
return (((a >> 51) & 0xFFF) == 0xFFE)
&& (a & UINT64_C(0x0007FFFFFFFFFFFF));
}
}
#endif
}
/*----------------------------------------------------------------------------
@ -778,21 +784,21 @@ static float64 propagateFloat64NaN(float64 a, float64 b, float_status *status)
int floatx80_is_quiet_nan(floatx80 a, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return floatx80_is_any_nan(a);
#else
if (snan_bit_is_one(status)) {
uint64_t aLow;
aLow = a.low & ~0x4000000000000000ULL;
return ((a.high & 0x7FFF) == 0x7FFF)
&& (aLow << 1)
&& (a.low == aLow);
if (no_signaling_nans(status)) {
return floatx80_is_any_nan(a);
} else {
return ((a.high & 0x7FFF) == 0x7FFF)
&& (UINT64_C(0x8000000000000000) <= ((uint64_t)(a.low << 1)));
if (snan_bit_is_one(status)) {
uint64_t aLow;
aLow = a.low & ~0x4000000000000000ULL;
return ((a.high & 0x7FFF) == 0x7FFF)
&& (aLow << 1)
&& (a.low == aLow);
} else {
return ((a.high & 0x7FFF) == 0x7FFF)
&& (UINT64_C(0x8000000000000000) <= ((uint64_t)(a.low << 1)));
}
}
#endif
}
/*----------------------------------------------------------------------------
@ -803,21 +809,21 @@ int floatx80_is_quiet_nan(floatx80 a, float_status *status)
int floatx80_is_signaling_nan(floatx80 a, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return 0;
#else
if (snan_bit_is_one(status)) {
return ((a.high & 0x7FFF) == 0x7FFF)
&& ((a.low << 1) >= 0x8000000000000000ULL);
if (no_signaling_nans(status)) {
return 0;
} else {
uint64_t aLow;
if (snan_bit_is_one(status)) {
return ((a.high & 0x7FFF) == 0x7FFF)
&& ((a.low << 1) >= 0x8000000000000000ULL);
} else {
uint64_t aLow;
aLow = a.low & ~UINT64_C(0x4000000000000000);
return ((a.high & 0x7FFF) == 0x7FFF)
&& (uint64_t)(aLow << 1)
&& (a.low == aLow);
aLow = a.low & ~UINT64_C(0x4000000000000000);
return ((a.high & 0x7FFF) == 0x7FFF)
&& (uint64_t)(aLow << 1)
&& (a.low == aLow);
}
}
#endif
}
/*----------------------------------------------------------------------------
@ -941,17 +947,17 @@ floatx80 propagateFloatx80NaN(floatx80 a, floatx80 b, float_status *status)
bool float128_is_quiet_nan(float128 a, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return float128_is_any_nan(a);
#else
if (snan_bit_is_one(status)) {
return (((a.high >> 47) & 0xFFFF) == 0xFFFE)
&& (a.low || (a.high & 0x00007FFFFFFFFFFFULL));
if (no_signaling_nans(status)) {
return float128_is_any_nan(a);
} else {
return ((a.high << 1) >= 0xFFFF000000000000ULL)
&& (a.low || (a.high & 0x0000FFFFFFFFFFFFULL));
if (snan_bit_is_one(status)) {
return (((a.high >> 47) & 0xFFFF) == 0xFFFE)
&& (a.low || (a.high & 0x00007FFFFFFFFFFFULL));
} else {
return ((a.high << 1) >= 0xFFFF000000000000ULL)
&& (a.low || (a.high & 0x0000FFFFFFFFFFFFULL));
}
}
#endif
}
/*----------------------------------------------------------------------------
@ -961,17 +967,17 @@ bool float128_is_quiet_nan(float128 a, float_status *status)
bool float128_is_signaling_nan(float128 a, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return 0;
#else
if (snan_bit_is_one(status)) {
return ((a.high << 1) >= 0xFFFF000000000000ULL)
&& (a.low || (a.high & 0x0000FFFFFFFFFFFFULL));
if (no_signaling_nans(status)) {
return 0;
} else {
return (((a.high >> 47) & 0xFFFF) == 0xFFFE)
&& (a.low || (a.high & UINT64_C(0x00007FFFFFFFFFFF)));
if (snan_bit_is_one(status)) {
return ((a.high << 1) >= 0xFFFF000000000000ULL)
&& (a.low || (a.high & 0x0000FFFFFFFFFFFFULL));
} else {
return (((a.high >> 47) & 0xFFFF) == 0xFFFE)
&& (a.low || (a.high & UINT64_C(0x00007FFFFFFFFFFF)));
}
}
#endif
}
/*----------------------------------------------------------------------------
@ -981,16 +987,16 @@ bool float128_is_signaling_nan(float128 a, float_status *status)
float128 float128_silence_nan(float128 a, float_status *status)
{
#ifdef NO_SIGNALING_NANS
g_assert_not_reached();
#else
if (snan_bit_is_one(status)) {
return float128_default_nan(status);
if (no_signaling_nans(status)) {
g_assert_not_reached();
} else {
a.high |= UINT64_C(0x0000800000000000);
return a;
if (snan_bit_is_one(status)) {
return float128_default_nan(status);
} else {
a.high |= UINT64_C(0x0000800000000000);
return a;
}
}
#endif
}
/*----------------------------------------------------------------------------

5
include/fpu/softfloat-helpers.h
View File

@ -95,6 +95,11 @@ static inline void set_snan_bit_is_one(bool val, float_status *status)
status->snan_bit_is_one = val;
}
static inline void set_no_signaling_nans(bool val, float_status *status)
{
status->no_signaling_nans = val;
}
static inline bool get_float_detect_tininess(float_status *status)
{
return status->tininess_before_rounding;

7
include/fpu/softfloat-types.h
View File

@ -165,8 +165,13 @@ typedef struct float_status {
/* should denormalised inputs go to zero and set the input_denormal flag? */
bool flush_inputs_to_zero;
bool default_nan_mode;
/* not always used -- see snan_bit_is_one() in softfloat-specialize.h */
/*
* The flags below are not used on all specializations and may
* constant fold away (see snan_bit_is_one()/no_signalling_nans() in
* softfloat-specialize.inc.c)
*/
bool snan_bit_is_one;
bool no_signaling_nans;
} float_status;
#endif /* SOFTFLOAT_TYPES_H */