[clang] [llvm] [RISCV] Add experimental support of Zaamo and Zalrsc (PR #78970)

[Craig Topper via cfe-commits]

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@@ -1105,7 +1129,7 @@ def FeatureForcedAtomics : SubtargetFeature<
     "forced-atomics", "HasForcedAtomics", "true",
     "Assume that lock-free native-width atomics are available">;
 def HasAtomicLdSt
-    : Predicate<"Subtarget->hasStdExtA() || Subtarget->hasForcedAtomics()">;
+    : Predicate<"Subtarget->hasStdExtA() || Subtarget->hasStdExtZalrsc() || Subtarget->hasForcedAtomics()">;
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topperc wrote:

This is only used by CodeGen patterns and should not be touched by an MC patch.

https://github.com/llvm/llvm-project/pull/78970