[vhdl] Handle garbage truncf input data#1002
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VHDL's `to_float32` function may fatally assert in simulation if the `float64` input value is out-of-range for a `float32` (e.g. exponent too large). This is generally not propblematic in dynamatic since C defines this as UB and therefore this is valid behavior for the compiler. However, the `truncf` circuit did not care to check whether `valid` is set and would just process its input data regardless of whether the input is valid, potentially leading to processing a `float64` leading to a simulator crash. This PR fixes this issue by simply masking the input when `valid` is not set. Very technically speaking this only exists to appease simulator semantics, though I'd hope synthesis can optimize out the check for equivalent circuits. Fixes #998
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VHDL's
to_float32function may fatally assert in simulation if thefloat64input value is out-of-range for afloat32(e.g. exponent too large). This is generally not propblematic in dynamatic since C defines this as UB and therefore this is valid behavior for the compiler.However, the
truncfcircuit did not care to check whethervalidis set and would just process its input data regardless of whether the input is valid, potentially leading to processing afloat64leading to a simulator crash.This PR fixes this issue by simply masking the input when
validis not set. Very technically speaking this only exists to appease simulator semantics, though I'd hope synthesis can optimize out the check for equivalent circuits.Fixes #998