[llvm] [AMDGPU] Add additional coverage tests for llvm.amdgcn.tanh, NFC (PR #202864)

[Matt Arsenault via llvm-commits]

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@@ -249,6 +349,182 @@ define amdgpu_kernel void @tanh_undef_f16(ptr addrspace(1) %out) #1 {
   ret void
 }
 
+define void @tanh_f16_v(ptr addrspace(1) %out, half %src) {
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arsenm wrote:

Same for the f16 cases 

https://github.com/llvm/llvm-project/pull/202864