[clang] [llvm] [RISCV] Add Spacemit X100 processor definition (PR #173988)

[Sam Elliott via cfe-commits]

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@@ -160,6 +160,14 @@
 // MCPU-SPACEMIT-X60-SAME: "-target-feature" "+xsmtvdot"
 // MCPU-SPACEMIT-X60-SAME: "-target-abi" "lp64d"
 
+// RUN: %clang --target=riscv64 -### -c %s 2>&1 -mcpu=spacemit-x100 | FileCheck -check-prefix=MCPU-SPACEMIT-X100 %s
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lenary wrote:

I think this new, minimal, version is better than listing all the extensions. I do see the value in checking that the name is accepted for both `-mcpu` and `-mtune` (rather than just printed as a supported cpu), which these few lines do. I don't see the point in checking the `-target-abi`

https://github.com/llvm/llvm-project/pull/173988