[llvm] [X86,SimplifyCFG] Use passthru to reduce select (PR #108754)

[Shengchen Kan via llvm-commits]

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@@ -674,6 +672,62 @@ if.false:
   ret void
 }
 
+define i32 @str_transcode0(i1 %cond1, ptr %p, i1 %cond2) {
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KanRobert wrote:

Probably rename this function? I assume the function name should show what it's testing.

https://github.com/llvm/llvm-project/pull/108754