Fix incorrect fusion of div and rem
#7567
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The JIT would generate code that calculated the remainder incorrectly
for the following example:
bug(Bin) ->
N = byte_size(Bin),
{N rem 128, N div 128}.
Essentially, the JIT would rewrite the code like this:
bug(Bin) ->
N = byte_size(Bin),
Q = N bsr 7,
{Q band 16#7f, Q}.
That is, the remainder would be calculated as `(N div 128) rem 128`.
Fixes erlang#7566
bjorng
added
team:VM
fhunleth
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to nerves-project/nerves_system_br
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Aug 25, 2023
See erlang/otp#7567 for details.
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The JIT would generate code that calculated the remainder incorrectly for the following example:
Essentially, the JIT would rewrite the code like this:
That is, the remainder would be calculated as
(N div 128) rem 128.Fixes #7566