mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

target/ppc: Merge COMPUTE_CLASS and COMPUTE_FPRF

Browse Source 
Instead of computing an artificial "class" bitmask then converting that
to the fprf value, compute the final value from the start.

Reorder the tests to check the most likely cases first.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230523202507.688859-1-richard.henderson@linaro.org>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
This commit is contained in:
Richard Henderson 2023-05-23 13:25:07 -07:00 committed by Daniel Henrique Barboza
parent 76f9ebffcd
commit 03ec9d9d22
1 changed files with 22 additions and 56 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

78
target/ppc/fpu_helper.c
View File

@ -141,62 +141,28 @@ static inline int ppc_float64_get_unbiased_exp(float64 f)
return ((f >> 52) & 0x7FF) - 1023;
}
/* Classify a floating-point number. */
enum {
is_normal = 1,
is_zero = 2,
is_denormal = 4,
is_inf = 8,
is_qnan = 16,
is_snan = 32,
is_neg = 64,
};
#define COMPUTE_CLASS(tp) \
static int tp##_classify(tp arg) \
{ \
int ret = tp##_is_neg(arg) * is_neg; \
if (unlikely(tp##_is_any_nan(arg))) { \
float_status dummy = { }; /* snan_bit_is_one = 0 */ \
ret |= (tp##_is_signaling_nan(arg, &dummy) \
? is_snan : is_qnan); \
} else if (unlikely(tp##_is_infinity(arg))) { \
ret |= is_inf; \
} else if (tp##_is_zero(arg)) { \
ret |= is_zero; \
} else if (tp##_is_zero_or_denormal(arg)) { \
ret |= is_denormal; \
} else { \
ret |= is_normal; \
} \
return ret; \
}
COMPUTE_CLASS(float16)
COMPUTE_CLASS(float32)
COMPUTE_CLASS(float64)
COMPUTE_CLASS(float128)
static void set_fprf_from_class(CPUPPCState *env, int class)
{
static const uint8_t fprf[6][2] = {
{ 0x04, 0x08 }, /* normalized */
{ 0x02, 0x12 }, /* zero */
{ 0x14, 0x18 }, /* denormalized */
{ 0x05, 0x09 }, /* infinity */
{ 0x11, 0x11 }, /* qnan */
{ 0x00, 0x00 }, /* snan -- flags are undefined */
};
bool isneg = class & is_neg;
env->fpscr &= ~FP_FPRF;
env->fpscr |= fprf[ctz32(class)][isneg] << FPSCR_FPRF;
}
#define COMPUTE_FPRF(tp) \
void helper_compute_fprf_##tp(CPUPPCState *env, tp arg) \
{ \
set_fprf_from_class(env, tp##_classify(arg)); \
#define COMPUTE_FPRF(tp) \
void helper_compute_fprf_##tp(CPUPPCState *env, tp arg) \
{ \
bool neg = tp##_is_neg(arg); \
target_ulong fprf; \
if (likely(tp##_is_normal(arg))) { \
fprf = neg ? 0x08 << FPSCR_FPRF : 0x04 << FPSCR_FPRF; \
} else if (tp##_is_zero(arg)) { \
fprf = neg ? 0x12 << FPSCR_FPRF : 0x02 << FPSCR_FPRF; \
} else if (tp##_is_zero_or_denormal(arg)) { \
fprf = neg ? 0x18 << FPSCR_FPRF : 0x14 << FPSCR_FPRF; \
} else if (tp##_is_infinity(arg)) { \
fprf = neg ? 0x09 << FPSCR_FPRF : 0x05 << FPSCR_FPRF; \
} else { \
float_status dummy = { }; /* snan_bit_is_one = 0 */ \
if (tp##_is_signaling_nan(arg, &dummy)) { \
fprf = 0x00 << FPSCR_FPRF; \
} else { \
fprf = 0x11 << FPSCR_FPRF; \
} \
} \
env->fpscr = (env->fpscr & ~FP_FPRF) | fprf; \
}
COMPUTE_FPRF(float16)