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

[Matt Arsenault via llvm-commits]

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@@ -758,11 +758,9 @@ 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)));
+      .clampScalar(0, s32, s128)
+      .legalIf(all(typeInSet(0, {s32, s64}), typeIs(1, p0)))
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arsenm wrote:

This legalIf isn't first? This can also be:
`.legalFor({{s32, p0}, {s64, p0})`

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