[clang] [Clang][LoongArch] Match GCC behaviour when parsing FPRs in asm clobbers (PR #138391)

[WÁNG Xuěruì via cfe-commits]

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@@ -5,6 +5,7 @@
 
 // CHECK-LABEL: @test_r0
 // CHECK: call void asm sideeffect "", "{$r0}"(i32 undef)
+// CHECK: call void asm sideeffect "", "{$r0}"(i32 undef)
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xen0n wrote:

Maybe we can use [the `CHECK-COUNT` directive](https://llvm.org/docs/CommandGuide/FileCheck.html#the-check-count-directive): `CHECK-COUNT-2` and a `CHECK-NOT`, to ensure there are exactly 2 lines having this content.

Otherwise LGTM, thanks!

https://github.com/llvm/llvm-project/pull/138391