diff options
Diffstat (limited to 'target-arm/helper.c')
| -rw-r--r-- | target-arm/helper.c | 332 |
1 files changed, 270 insertions, 62 deletions
diff --git a/target-arm/helper.c b/target-arm/helper.c index f0a1fd48e6..55077ed1b6 100644 --- a/target-arm/helper.c +++ b/target-arm/helper.c @@ -1983,6 +1983,7 @@ void register_cp_regs_for_features(ARMCPU *cpu) ARMCPRegInfo pmcr = { .name = "PMCR", .cp = 15, .crn = 9, .crm = 12, .opc1 = 0, .opc2 = 0, .access = PL0_RW, .resetvalue = cpu->midr & 0xff000000, + .type = ARM_CP_IO, .fieldoffset = offsetof(CPUARMState, cp15.c9_pmcr), .accessfn = pmreg_access, .writefn = pmcr_write, .raw_writefn = raw_write, @@ -4519,16 +4520,21 @@ float32 HELPER(rsqrts_f32)(float32 a, float32 b, CPUARMState *env) * int->float conversions at run-time. */ #define float64_256 make_float64(0x4070000000000000LL) #define float64_512 make_float64(0x4080000000000000LL) +#define float32_maxnorm make_float32(0x7f7fffff) +#define float64_maxnorm make_float64(0x7fefffffffffffffLL) -/* The algorithm that must be used to calculate the estimate - * is specified by the ARM ARM. +/* Reciprocal functions + * + * The algorithm that must be used to calculate the estimate + * is specified by the ARM ARM, see FPRecipEstimate() */ -static float64 recip_estimate(float64 a, CPUARMState *env) + +static float64 recip_estimate(float64 a, float_status *real_fp_status) { /* These calculations mustn't set any fp exception flags, * so we use a local copy of the fp_status. */ - float_status dummy_status = env->vfp.standard_fp_status; + float_status dummy_status = *real_fp_status; float_status *s = &dummy_status; /* q = (int)(a * 512.0) */ float64 q = float64_mul(float64_512, a, s); @@ -4549,56 +4555,178 @@ static float64 recip_estimate(float64 a, CPUARMState *env) return float64_div(int64_to_float64(q_int, s), float64_256, s); } -float32 HELPER(recpe_f32)(float32 a, CPUARMState *env) +/* Common wrapper to call recip_estimate */ +static float64 call_recip_estimate(float64 num, int off, float_status *fpst) { - float_status *s = &env->vfp.standard_fp_status; - float64 f64; - uint32_t val32 = float32_val(a); + uint64_t val64 = float64_val(num); + uint64_t frac = extract64(val64, 0, 52); + int64_t exp = extract64(val64, 52, 11); + uint64_t sbit; + float64 scaled, estimate; - int result_exp; - int a_exp = (val32 & 0x7f800000) >> 23; - int sign = val32 & 0x80000000; + /* Generate the scaled number for the estimate function */ + if (exp == 0) { + if (extract64(frac, 51, 1) == 0) { + exp = -1; + frac = extract64(frac, 0, 50) << 2; + } else { + frac = extract64(frac, 0, 51) << 1; + } + } - if (float32_is_any_nan(a)) { - if (float32_is_signaling_nan(a)) { - float_raise(float_flag_invalid, s); + /* scaled = '0' : '01111111110' : fraction<51:44> : Zeros(44); */ + scaled = make_float64((0x3feULL << 52) + | extract64(frac, 44, 8) << 44); + + estimate = recip_estimate(scaled, fpst); + + /* Build new result */ + val64 = float64_val(estimate); + sbit = 0x8000000000000000ULL & val64; + exp = off - exp; + frac = extract64(val64, 0, 52); + + if (exp == 0) { + frac = 1ULL << 51 | extract64(frac, 1, 51); + } else if (exp == -1) { + frac = 1ULL << 50 | extract64(frac, 2, 50); + exp = 0; + } + + return make_float64(sbit | (exp << 52) | frac); +} + +static bool round_to_inf(float_status *fpst, bool sign_bit) +{ + switch (fpst->float_rounding_mode) { + case float_round_nearest_even: /* Round to Nearest */ + return true; + case float_round_up: /* Round to +Inf */ + return !sign_bit; + case float_round_down: /* Round to -Inf */ + return sign_bit; + case float_round_to_zero: /* Round to Zero */ + return false; + } + + g_assert_not_reached(); +} + +float32 HELPER(recpe_f32)(float32 input, void *fpstp) +{ + float_status *fpst = fpstp; + float32 f32 = float32_squash_input_denormal(input, fpst); + uint32_t f32_val = float32_val(f32); + uint32_t f32_sbit = 0x80000000ULL & f32_val; + int32_t f32_exp = extract32(f32_val, 23, 8); + uint32_t f32_frac = extract32(f32_val, 0, 23); + float64 f64, r64; + uint64_t r64_val; + int64_t r64_exp; + uint64_t r64_frac; + + if (float32_is_any_nan(f32)) { + float32 nan = f32; + if (float32_is_signaling_nan(f32)) { + float_raise(float_flag_invalid, fpst); + nan = float32_maybe_silence_nan(f32); } - return float32_default_nan; - } else if (float32_is_infinity(a)) { - return float32_set_sign(float32_zero, float32_is_neg(a)); - } else if (float32_is_zero_or_denormal(a)) { - if (!float32_is_zero(a)) { - float_raise(float_flag_input_denormal, s); + if (fpst->default_nan_mode) { + nan = float32_default_nan; } - float_raise(float_flag_divbyzero, s); - return float32_set_sign(float32_infinity, float32_is_neg(a)); - } else if (a_exp >= 253) { - float_raise(float_flag_underflow, s); - return float32_set_sign(float32_zero, float32_is_neg(a)); + return nan; + } else if (float32_is_infinity(f32)) { + return float32_set_sign(float32_zero, float32_is_neg(f32)); + } else if (float32_is_zero(f32)) { + float_raise(float_flag_divbyzero, fpst); + return float32_set_sign(float32_infinity, float32_is_neg(f32)); + } else if ((f32_val & ~(1ULL << 31)) < (1ULL << 21)) { + /* Abs(value) < 2.0^-128 */ + float_raise(float_flag_overflow | float_flag_inexact, fpst); + if (round_to_inf(fpst, f32_sbit)) { + return float32_set_sign(float32_infinity, float32_is_neg(f32)); + } else { + return float32_set_sign(float32_maxnorm, float32_is_neg(f32)); + } + } else if (f32_exp >= 253 && fpst->flush_to_zero) { + float_raise(float_flag_underflow, fpst); + return float32_set_sign(float32_zero, float32_is_neg(f32)); } - f64 = make_float64((0x3feULL << 52) - | ((int64_t)(val32 & 0x7fffff) << 29)); - result_exp = 253 - a_exp; + f64 = make_float64(((int64_t)(f32_exp) << 52) | (int64_t)(f32_frac) << 29); + r64 = call_recip_estimate(f64, 253, fpst); + r64_val = float64_val(r64); + r64_exp = extract64(r64_val, 52, 11); + r64_frac = extract64(r64_val, 0, 52); - f64 = recip_estimate(f64, env); + /* result = sign : result_exp<7:0> : fraction<51:29>; */ + return make_float32(f32_sbit | + (r64_exp & 0xff) << 23 | + extract64(r64_frac, 29, 24)); +} - val32 = sign - | ((result_exp & 0xff) << 23) - | ((float64_val(f64) >> 29) & 0x7fffff); - return make_float32(val32); +float64 HELPER(recpe_f64)(float64 input, void *fpstp) +{ + float_status *fpst = fpstp; + float64 f64 = float64_squash_input_denormal(input, fpst); + uint64_t f64_val = float64_val(f64); + uint64_t f64_sbit = 0x8000000000000000ULL & f64_val; + int64_t f64_exp = extract64(f64_val, 52, 11); + float64 r64; + uint64_t r64_val; + int64_t r64_exp; + uint64_t r64_frac; + + /* Deal with any special cases */ + if (float64_is_any_nan(f64)) { + float64 nan = f64; + if (float64_is_signaling_nan(f64)) { + float_raise(float_flag_invalid, fpst); + nan = float64_maybe_silence_nan(f64); + } + if (fpst->default_nan_mode) { + nan = float64_default_nan; + } + return nan; + } else if (float64_is_infinity(f64)) { + return float64_set_sign(float64_zero, float64_is_neg(f64)); + } else if (float64_is_zero(f64)) { + float_raise(float_flag_divbyzero, fpst); + return float64_set_sign(float64_infinity, float64_is_neg(f64)); + } else if ((f64_val & ~(1ULL << 63)) < (1ULL << 50)) { + /* Abs(value) < 2.0^-1024 */ + float_raise(float_flag_overflow | float_flag_inexact, fpst); + if (round_to_inf(fpst, f64_sbit)) { + return float64_set_sign(float64_infinity, float64_is_neg(f64)); + } else { + return float64_set_sign(float64_maxnorm, float64_is_neg(f64)); + } + } else if (f64_exp >= 1023 && fpst->flush_to_zero) { + float_raise(float_flag_underflow, fpst); + return float64_set_sign(float64_zero, float64_is_neg(f64)); + } + + r64 = call_recip_estimate(f64, 2045, fpst); + r64_val = float64_val(r64); + r64_exp = extract64(r64_val, 52, 11); + r64_frac = extract64(r64_val, 0, 52); + + /* result = sign : result_exp<10:0> : fraction<51:0> */ + return make_float64(f64_sbit | + ((r64_exp & 0x7ff) << 52) | + r64_frac); } /* The algorithm that must be used to calculate the estimate * is specified by the ARM ARM. */ -static float64 recip_sqrt_estimate(float64 a, CPUARMState *env) +static float64 recip_sqrt_estimate(float64 a, float_status *real_fp_status) { /* These calculations mustn't set any fp exception flags, * so we use a local copy of the fp_status. */ - float_status dummy_status = env->vfp.standard_fp_status; + float_status dummy_status = *real_fp_status; float_status *s = &dummy_status; float64 q; int64_t q_int; @@ -4645,49 +4773,64 @@ static float64 recip_sqrt_estimate(float64 a, CPUARMState *env) return float64_div(int64_to_float64(q_int, s), float64_256, s); } -float32 HELPER(rsqrte_f32)(float32 a, CPUARMState *env) +float32 HELPER(rsqrte_f32)(float32 input, void *fpstp) { - float_status *s = &env->vfp.standard_fp_status; + float_status *s = fpstp; + float32 f32 = float32_squash_input_denormal(input, s); + uint32_t val = float32_val(f32); + uint32_t f32_sbit = 0x80000000 & val; + int32_t f32_exp = extract32(val, 23, 8); + uint32_t f32_frac = extract32(val, 0, 23); + uint64_t f64_frac; + uint64_t val64; int result_exp; float64 f64; - uint32_t val; - uint64_t val64; - - val = float32_val(a); - if (float32_is_any_nan(a)) { - if (float32_is_signaling_nan(a)) { + if (float32_is_any_nan(f32)) { + float32 nan = f32; + if (float32_is_signaling_nan(f32)) { float_raise(float_flag_invalid, s); + nan = float32_maybe_silence_nan(f32); } - return float32_default_nan; - } else if (float32_is_zero_or_denormal(a)) { - if (!float32_is_zero(a)) { - float_raise(float_flag_input_denormal, s); + if (s->default_nan_mode) { + nan = float32_default_nan; } + return nan; + } else if (float32_is_zero(f32)) { float_raise(float_flag_divbyzero, s); - return float32_set_sign(float32_infinity, float32_is_neg(a)); - } else if (float32_is_neg(a)) { + return float32_set_sign(float32_infinity, float32_is_neg(f32)); + } else if (float32_is_neg(f32)) { float_raise(float_flag_invalid, s); return float32_default_nan; - } else if (float32_is_infinity(a)) { + } else if (float32_is_infinity(f32)) { return float32_zero; } - /* Normalize to a double-precision value between 0.25 and 1.0, + /* Scale and normalize to a double-precision value between 0.25 and 1.0, * preserving the parity of the exponent. */ - if ((val & 0x800000) == 0) { - f64 = make_float64(((uint64_t)(val & 0x80000000) << 32) + + f64_frac = ((uint64_t) f32_frac) << 29; + if (f32_exp == 0) { + while (extract64(f64_frac, 51, 1) == 0) { + f64_frac = f64_frac << 1; + f32_exp = f32_exp-1; + } + f64_frac = extract64(f64_frac, 0, 51) << 1; + } + + if (extract64(f32_exp, 0, 1) == 0) { + f64 = make_float64(((uint64_t) f32_sbit) << 32 | (0x3feULL << 52) - | ((uint64_t)(val & 0x7fffff) << 29)); + | f64_frac); } else { - f64 = make_float64(((uint64_t)(val & 0x80000000) << 32) + f64 = make_float64(((uint64_t) f32_sbit) << 32 | (0x3fdULL << 52) - | ((uint64_t)(val & 0x7fffff) << 29)); + | f64_frac); } - result_exp = (380 - ((val & 0x7f800000) >> 23)) / 2; + result_exp = (380 - f32_exp) / 2; - f64 = recip_sqrt_estimate(f64, env); + f64 = recip_sqrt_estimate(f64, s); val64 = float64_val(f64); @@ -4696,8 +4839,72 @@ float32 HELPER(rsqrte_f32)(float32 a, CPUARMState *env) return make_float32(val); } -uint32_t HELPER(recpe_u32)(uint32_t a, CPUARMState *env) +float64 HELPER(rsqrte_f64)(float64 input, void *fpstp) +{ + float_status *s = fpstp; + float64 f64 = float64_squash_input_denormal(input, s); + uint64_t val = float64_val(f64); + uint64_t f64_sbit = 0x8000000000000000ULL & val; + int64_t f64_exp = extract64(val, 52, 11); + uint64_t f64_frac = extract64(val, 0, 52); + int64_t result_exp; + uint64_t result_frac; + + if (float64_is_any_nan(f64)) { + float64 nan = f64; + if (float64_is_signaling_nan(f64)) { + float_raise(float_flag_invalid, s); + nan = float64_maybe_silence_nan(f64); + } + if (s->default_nan_mode) { + nan = float64_default_nan; + } + return nan; + } else if (float64_is_zero(f64)) { + float_raise(float_flag_divbyzero, s); + return float64_set_sign(float64_infinity, float64_is_neg(f64)); + } else if (float64_is_neg(f64)) { + float_raise(float_flag_invalid, s); + return float64_default_nan; + } else if (float64_is_infinity(f64)) { + return float64_zero; + } + + /* Scale and normalize to a double-precision value between 0.25 and 1.0, + * preserving the parity of the exponent. */ + + if (f64_exp == 0) { + while (extract64(f64_frac, 51, 1) == 0) { + f64_frac = f64_frac << 1; + f64_exp = f64_exp - 1; + } + f64_frac = extract64(f64_frac, 0, 51) << 1; + } + + if (extract64(f64_exp, 0, 1) == 0) { + f64 = make_float64(f64_sbit + | (0x3feULL << 52) + | f64_frac); + } else { + f64 = make_float64(f64_sbit + | (0x3fdULL << 52) + | f64_frac); + } + + result_exp = (3068 - f64_exp) / 2; + + f64 = recip_sqrt_estimate(f64, s); + + result_frac = extract64(float64_val(f64), 0, 52); + + return make_float64(f64_sbit | + ((result_exp & 0x7ff) << 52) | + result_frac); +} + +uint32_t HELPER(recpe_u32)(uint32_t a, void *fpstp) { + float_status *s = fpstp; float64 f64; if ((a & 0x80000000) == 0) { @@ -4707,13 +4914,14 @@ uint32_t HELPER(recpe_u32)(uint32_t a, CPUARMState *env) f64 = make_float64((0x3feULL << 52) | ((int64_t)(a & 0x7fffffff) << 21)); - f64 = recip_estimate (f64, env); + f64 = recip_estimate(f64, s); return 0x80000000 | ((float64_val(f64) >> 21) & 0x7fffffff); } -uint32_t HELPER(rsqrte_u32)(uint32_t a, CPUARMState *env) +uint32_t HELPER(rsqrte_u32)(uint32_t a, void *fpstp) { + float_status *fpst = fpstp; float64 f64; if ((a & 0xc0000000) == 0) { @@ -4728,7 +4936,7 @@ uint32_t HELPER(rsqrte_u32)(uint32_t a, CPUARMState *env) | ((uint64_t)(a & 0x3fffffff) << 22)); } - f64 = recip_sqrt_estimate(f64, env); + f64 = recip_sqrt_estimate(f64, fpst); return 0x80000000 | ((float64_val(f64) >> 21) & 0x7fffffff); } |