[llvm] [AMDGPU] Re-Re-apply: Implement vop3p complex pattern optmization for gisel (PR #146984)

[Juan Manuel Martinez Caamaño via llvm-commits]

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@@ -474,7 +474,7 @@ def have_cxx_shared_library():
         print("could not exec llvm-readobj")
         return False
 
-    readobj_out = readobj_cmd.stdout.read().decode("ascii")
+    readobj_out = readobj_cmd.stdout.read().decode("utf-8")
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jmmartinez wrote:

I think this is a leftover.

https://github.com/llvm/llvm-project/pull/146984