[llvm] [RISCV] Add P-ext MC support for pli.dh, pli.db, and plui.dh. (PR #153972)

[Piotr Fusik via llvm-commits]

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@@ -25,7 +25,7 @@ def SImm8UnsignedAsmOperand : SImmAsmOperand<8, "Unsigned"> {
 }
 
 // A 8-bit signed immediate allowing range [-128, 255]
-// but represented as [-128, 127].
+// but represented as [-128, 255].
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pfusik wrote:

What do you mean by "but" if the two ranges are identical?

https://github.com/llvm/llvm-project/pull/153972