[llvm] [VP][RISCV] Introduce vp.splat and RISC-V. (PR #98731)

[Yeting Kuo via llvm-commits]

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@@ -22841,6 +22841,51 @@ Examples:
  llvm.experimental.vp.splice(<A,B,C,D>, <E,F,G,H>, -2, 3, 2); ==> <B, C, poison, poison> trailing elements
 
 
+.. _int_experimental_vp_splat:
+
+
+'``llvm.experimental.vp.splat``' Intrinsic
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Syntax:
+"""""""
+This is an overloaded intrinsic.
+
+::
+
+      declare <2 x double> @llvm.experimental.vp.splat.v2f64(<2 x double> %vec, <2 x i1> %mask, i32 %evl)
+      declare <vscale x 4 x i32> @llvm.experimental.vp.splat.nxv4i32(<vscale x 4 x i32> %vec, <vscale x 4 x i1> %mask, i32 %evl)
+
+Overview:
+"""""""""
+
+The '``llvm.experimental.vp.splat.*``' intrinsic is to create a prdicated splat
+with specific effective vector length.
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yetingk wrote:

Done.

https://github.com/llvm/llvm-project/pull/98731