[llvm] [TableGen, CodeGen, CHERI] Add support for the cPTR wildcard value type. (PR #158426)

[Andrew Adams via llvm-commits]

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@@ -367,6 +367,10 @@ def aarch64mfp8 : ValueType<8,  253>;  // 8-bit value in FPR (AArch64)
 def c64 : VTCheriCapability<64, 254>;   // 64-bit CHERI capability value
 def c128 : VTCheriCapability<128, 255>; // 128-bit CHERI capability value
 
+// Pseudo valuetype mapped to the current CHERI capability pointer size.
+// Should only be used in TableGen.
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abadams wrote:

Doing that drops it back to 0.5 MB, yes. Though the class probably still shouldn't be on the stack.

https://github.com/llvm/llvm-project/pull/158426