[llvm] Add diagnostic help for inline asm operand constraint 'H' (PR #88248)

[Jessica Clarke via llvm-commits]

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@@ -13,8 +14,20 @@ entry:
 }
 
 ; CHECK-label:test_twinword_error
+; CHECK: error: invalid operand in inline asm: 'rd %asr5, ${0:L}
+; CHECK: srlx ${0:L}, 32, ${0:H}'
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jrtc27 wrote:

Why's this on a new line?

https://github.com/llvm/llvm-project/pull/88248