Implement handling of divide by zero in amd64 backend

[twitchyliquid64]

Fixes #165

[codecov-io]

Codecov Report

Merging #167 into master will increase coverage by 0.09%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #167      +/-   ##
==========================================
+ Coverage   69.61%   69.71%   +0.09%     
==========================================
  Files          48       48              
  Lines        5466     5484      +18     
==========================================
+ Hits         3805     3823      +18     
  Misses       1317     1317              
  Partials      344      344

Impacted Files	Coverage Δ
exec/internal/compile/native.go	54.54% <ø> (ø)	⬆️
exec/native_compile.go	66.21% <100%> (+0.93%)	⬆️
exec/internal/compile/backend_amd64.go	80.32% <100%> (+0.35%)	⬆️

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