[llvm] [RISCV][GlobalISel] Legalize and select G_ATOMICRMW_ADD instruction (PR #153791)

[Kane Wang via llvm-commits]

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@@ -729,6 +736,16 @@ bool RISCVLegalizerInfo::legalizeIntrinsic(LegalizerHelper &Helper,
     MI.eraseFromParent();
     return true;
   }
+  case Intrinsic::riscv_masked_atomicrmw_xchg:
+  case Intrinsic::riscv_masked_atomicrmw_add:
+  case Intrinsic::riscv_masked_atomicrmw_sub:
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ReVe1uv wrote:

I've removed the cases other than "add" since only "add" is currently tested.

https://github.com/llvm/llvm-project/pull/153791