[llvm] [LLVM] Slay undead copysign code (PR #111269)

[via llvm-commits]

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@@ -438,7 +442,15 @@ void IntrinsicLowering::LowerIntrinsicCall(CallInst *CI) {
     break;
   }
   case Intrinsic::copysign: {
-    ReplaceFPIntrinsicWithCall(CI, "copysignf", "copysign", "copysignl");
+    switch (CI->getArgOperand(0)->getType()->getTypeID()) {
+    default:
+      assert(false && "only need a copysign libcall for arch-specific floats");
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workingjubilee wrote:

`report_fatal_error` sounds good to me. I just hadn't thought terribly hard about error-handling aside from "hm, this change might let weird IR flow downstream, maybe this spot which serves as a backstop for such should assert more".

https://github.com/llvm/llvm-project/pull/111269