[llvm] [LoongArch] Introduce `32s` target feature for LA32S ISA extensions (PR #139695)

[WÁNG Xuěruì via llvm-commits]

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@@ -214,8 +214,9 @@ static void doAtomicBinOpExpansion(const LoongArchInstrInfo *TII,
       .addReg(ScratchReg)
       .addReg(AddrReg)
       .addImm(0);
-  BuildMI(LoopMBB, DL, TII->get(LoongArch::BEQZ))
+  BuildMI(LoopMBB, DL, TII->get(LoongArch::BEQ))
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xen0n wrote:

`BEQZ` has the advantage over `BEQ` in that its reach is broader by 5 bits (width of a GPR slot), so if some of the changed bits potentially refers to a remote MBB, we may want to preserve them? I'm not looking at this code as closely as I'd prefer because I'm just battling my procrastination and doing a quick review here.

https://github.com/llvm/llvm-project/pull/139695