[clang] [llvm] [RISCV][MC] Implement MC for Base P extension (PR #123271)

[Craig Topper via cfe-commits]

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@@ -0,0 +1,1440 @@
+// NOTE: Assertions have been autogenerated by utils/update_mc_test_checks.py UTC_ARGS: --tool ./llvm-objdump --version 5
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topperc wrote:

What does the --tool here do?

https://github.com/llvm/llvm-project/pull/123271