[llvm] [BOLT][NFC] Add isRIPRel and isIndexed helpers (PR #91661)

[Davide Italiano via llvm-commits]

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@@ -1932,6 +1932,19 @@ class X86MCPlusBuilder : public MCPlusBuilder {
     //    = R_X86_64_PC32(Ln) + En - JT
     //    = R_X86_64_PC32(Ln + offsetof(En))
     //
+    auto isRIPRel = [&](X86MemOperand &MO) {
+      // NB: DispExpr should be set
+      return MO.DispExpr != nullptr &&
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dcci wrote:

this is adding this extra check, `MO.DispExpr != nullptr` -- why?

https://github.com/llvm/llvm-project/pull/91661