[llvm] [AArch64] Put legal action first for G_ATOMIC_CMPXCHG (PR #74613)

[David Green via llvm-commits]

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@@ -758,18 +758,16 @@ AArch64LegalizerInfo::AArch64LegalizerInfo(const AArch64Subtarget &ST)
           all(typeInSet(0, {s8, s16, s32, s64, s128}), typeIs(2, p0)));
 
   getActionDefinitionsBuilder(G_ATOMIC_CMPXCHG)
-      .customIf([](const LegalityQuery &Query) {
-        return Query.Types[0].getSizeInBits() == 128;
-      })
-      .clampScalar(0, s32, s64)
-      .legalIf(all(typeInSet(0, {s32, s64}), typeIs(1, p0)));
+      .legalFor({{s32, p0}, {s64, p0}})
+      .customIf(typeIs(0, s128))
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davemgreen wrote:

(It might be better to keep it in just to be explicit about the types that are supported.)

https://github.com/llvm/llvm-project/pull/74613