[llvm] [RISCV] Add QingKe "XW" compressed opcode extension (PR #97925)

[Craig Topper via llvm-commits]

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@@ -737,6 +737,7 @@ Error RISCVISAInfo::checkDependency() {
   bool HasI = Exts.count("i") != 0;
   bool HasC = Exts.count("c") != 0;
   bool HasF = Exts.count("f") != 0;
+  bool HasD = Exts.count("d") != 0;
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topperc wrote:

If you add this here at the top level, please replace all the other usage of `Exts.count("d")` in the code. Otherwise keep this under your new code block.

https://github.com/llvm/llvm-project/pull/97925