diff options
Diffstat (limited to 'chapters/introduction.adoc')
| -rw-r--r-- | chapters/introduction.adoc | 33 |
1 files changed, 14 insertions, 19 deletions
diff --git a/chapters/introduction.adoc b/chapters/introduction.adoc index b72472a..fd9ec25 100644 --- a/chapters/introduction.adoc +++ b/chapters/introduction.adoc @@ -204,11 +204,19 @@ A compliant implementation must satisfy the following: ===== Main Inference precision requirements -In a compliant implementation, individual-floating point operations within the graph must meet the following accuracy bounds -listed in the table below. In the table _ulp_ means unit of the last place. +In a compliant implementation, individual floating-point operations within the graph must meet the accuracy bounds listed in the table following. +In the table _ulp_ means unit of the last place. +The function tosa_reference_check_fp() defines the error range permitted by a given number of units of last place in this specification. NOTE: The error criteria in this section are at an early draft stage and are likely to change during conformance test development. +Error criteria are specified for a single operator. +For a sequence of n operators, A[0] to A[n-1], there must be corresponding implementations, I[0] to I[n-1], such that: + +* Each I[k] implements A[k] with same or higher precision datatypes +* Each I[k] meets the accuracy defined in this specification for the A[k] precision +* The accuracy of the sequence A[0] to A[n-1] is no worse than the accuracy of the sequence I[0] to I[n-1] + The following criteria apply to all operations: * If any input is a NaN and the result is floating-point then the result must be a NaN @@ -241,15 +249,14 @@ Floating-point result underflows must be set to zero of the correct sign. + Addition of infinites of different signs must produce a NaN. + Subtraction of infinities of the same sign must produce a NaN. + Multiplication of an infinity by a zero must produce a NaN. + -Otherwise for fp32_t the result must be rounded to the nearest representable value using the round to nearest, ties to even rounding mode. + -Otherwise for fp16_t and bf16_t the result must be within 0.5 ulp of the mathematical result. +Otherwise the result must be within 0.5 ulp of the mathematical result. | <<CAST>> | Floating-point result overflows must be set to infinity of the correct sign. + Floating-point result underflows must be set to zero of the correct sign. + Cast from floating-point to integer result overflows must be saturated. + -Otherwise for fp32_t the result must be rounded to the nearest representable value using the round to nearest, ties to even rounding mode. + -Otherwise for fp16_t and bf16_t the result must be within 0.5 ulp of the mathematical result. +Cast from floating-point to integer must be rounded using round to nearest, ties to even, rounding mode. + +Otherwise cast to floating-point must be within 0.5 ulp of the mathematical result. | <<RECIPROCAL>> | If the input is a zero or the result overlows the output must be an infinity of the same sign. + @@ -334,18 +341,6 @@ size_t T = tensor_size(output_shape) // number dot product results size_t ksb = (max_value(bias_abs) > 0) ? (KS + 1) : KS; // kernel size and bias fp64_t out_err_sum = 0.0; fp64_t out_err_sumsq = 0.0; -fp64_t acc_prec; // 1<<(M+1) where M is the number of mantissa bits -fp64_t acc_min_normal; // accumulator minimum normal greater than zero -fp64_t two_m42 = 1.0/static_cast<fp64_t>((int64_t)1<<42); // pow(2, -42) -switch (acc_t) { - case fp32_t: acc_prec = static_cast<fp64_t>(1<<24); // pow(2, 24) - acc_min_normal = two_m42 * two_m42 * two_m42; // pow(2, -126) - break; - case fp16_t: acc_prec = static_cast<fp64_t>(1<<11); // pow(2, 11) - acc_min_normal = 1.0/static_cast<fp64_t>(1<<14); // pow(2, -14) - break; - default: ERROR_IF(true); -} for_each(index in output_shape) { fp64_t out_bnd = tensor_read<fp64_t>(output_bnd, output_shape, index); fp64_t out_ref = tensor_read<fp64_t>(output_ref, output_shape, index); @@ -358,7 +353,7 @@ for_each(index in output_shape) { REQUIRE(out_ref == 0.0 && out_imp == 0.0); out_err = 0.0; } else { // 0.0 < out_bnd < infinity - fp64_t out_err_bnd = max(out_bnd / acc_prec, acc_min_normal); + fp64_t out_err_bnd = max(out_bnd * exp2(-1-normal_frac<acc_t>()), normal_min<acc_t>()); out_err = (static_cast<fp64_t>(out_imp) - out_ref) / out_err_bnd; REQUIRE(abs(out_err) <= ksb); } |