[lld] [lld] Add thunks for hexagon (PR #111217)

[Fangrui Song via llvm-commits]

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@@ -1531,6 +1579,21 @@ static Thunk *addThunkAVR(Ctx &ctx, RelType type, Symbol &s, int64_t a) {
   }
 }
 
+static Thunk *addThunkHexagon(Ctx &ctx, const InputSection &isec,
+                              Relocation &rel, Symbol &s) {
+  switch (rel.type) {
+  case R_HEX_B9_PCREL:
+  case R_HEX_B13_PCREL:
+  case R_HEX_B15_PCREL:
+  case R_HEX_B22_PCREL:
+  case R_HEX_PLT_B22_PCREL:
+  case R_HEX_GD_PLT_B22_PCREL:
+    return make<HexagonThunk>(ctx, isec, rel, s);
+  default:
+    fatal("unrecognized relocation type " + toString(rel.type));
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MaskRay wrote:

llvm_unreachable

ensure this indeed unreachable

https://github.com/llvm/llvm-project/pull/111217