[clang] [llvm] [IR] Memory locations for floating-point operations (PR #226826)

[Serge Pavlov via cfe-commits]

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@@ -285,7 +285,7 @@ static void addMemoryAttrs(const SCCNodeSet &SCCNodes, AARGetterT &&AARGetter,
     ME |= FnME;
     RecursiveArgME |= FnRecursiveArgME;
     // Reached bottom of the lattice, we will not be able to improve the result.
-    if (ME == MemoryEffects::unknown())
+    if (ME == MemoryEffects::unknown_mem())
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spavloff wrote:

Now `unknown_mem` is removed.

FP access has more complicated restrictions. For example read access to FP status bits require setting `strictfp` attribute. The initial intent was to uses `NoModRef` for FP locations as this is the common case. Now it requires more careful treatment in attribute deduction.

https://github.com/llvm/llvm-project/pull/226826