[LoongArch] Ignore warnings when there is no environment in triple

[hev]

Summary

In Rust bare-metal targets, there is no environment component in triple name. This patch ignores warnings that look like:

warning: triple-implied ABI conflicts with provided target-abi ‘lp64s', using target-abi

[SixWeining]

The change makes sense to me.

[xen0n]

Thanks! A test case would be appreciated though.

[hev]

Add test cases.

[xen0n]

llvm/test/CodeGen/LoongArch/target-abi-from-triple-edge-cases.ll

19 ↗

(On Diff #530808)

grammatical nit: "for there are" -> "when there is"

26–27 ↗

(On Diff #530808)

Since the intent here is just making sure no warning is emitted, and that the warning's exact form is already checked above, maybe we could coalesce the two into one as simple as NO-WARNING-NOT: warning?

[hev]

Update test case.

[xen0n]

Thanks!

llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchBaseInfo.cpp

     break;
   }
 
-  if (!ABIName.empty() && ArgProvidedABI != TripleABI)
+  if (!ABIName.empty() && TT.hasEnvironment() && ArgProvidedABI != TripleABI)
     errs() << "warning: triple-implied ABI conflicts with provided target-abi '"
            << ABIName << "', using target-abi\n";