[llvm] [PowerPC] Implement paddis (PR #161572)

[Maryam Moghadas via llvm-commits]

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@@ -7,10 +7,10 @@
 paddi 1, 1, 32, 1
 
 # CHECK: error: invalid operand for instruction
-pld 1, 32(1), 1
+paddis 10, 5, 1000000000, 1
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maryammo wrote:

paddis is ISAFuture instruction but test added to ISA31 errors file.

https://github.com/llvm/llvm-project/pull/161572