================
@@ -102,6 +102,16 @@ Deprecated Compiler Flags
 Modified Compiler Flags
 -----------------------
 
+- The ``-ffp-model`` option has been updated to enable a more limited set of
+  optimizations when the ``fast`` argument is used and to accept a new 
argument,
+  ``aggressive``. The behavior of ``-ffp-model=aggressive`` is equivalent
+  to the previous behavior of ``-ffp-model=fast``. The updated
+  ``-ffp-model=fast`` behavior no longer assumes finite math only, uses
+  the ``promoted`` algorithm for complex division when possible rather than the
+  less basic (limited range) algorithm, and sets
+  ``-ffp-contract=fast-honor-pragmas`` rather than ``-ffp-contract=fast``.
----------------
andykaylor wrote:

It is a silent change, but the new behavior is within the bounds of what the 
existing option permits. There is never any guarantee that any given 
optimization will be performed, so this won't break anyone's code (unless some 
optimization is masking a real error in the code). There may be some cases 
where it will introduce a performance regression, but I think those are likely 
to be minor regressions. In the case of complex division, the change could 
result in a numeric difference but the new results will be more accurate and 
the fast fp-model doesn't guarantee numeric consistency.

https://github.com/llvm/llvm-project/pull/100453
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