There was a bug in float32_to_s that incorrectly mapped a zero exponent
to 0x38. This meant 0.0f != 0. At the same time, fix a generic type
punning bug in helper_memory_to_s and helper_s_to_memory.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
d0af544555