[llvm] [X86][GlobalISel] Support globals in pic mode (PR #170038)

[Evgenii Kudriashov via llvm-commits]

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@@ -41,6 +41,14 @@ def G_FLDCW16 : X86GenericInstruction {
   let mayLoad = true;
 }
 
+// RIP-relative address wrapper for PIC mode global access.
+// Equivalent to X86ISD::WrapperRIP in SelectionDAG.
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e-kud wrote:

There are no patterns with `X86ISD::WrapperRIP`, it is primarily used in C++ code, especially in `selectAddr` so we keep the same logic in GlobalISel. In other words, no need in `GINodeEquiv` as there is nothing to match.



https://github.com/llvm/llvm-project/pull/170038