[clang] [NFC] Move warning from CodeGen to Sema. (PR #107397)

[Aaron Ballman via cfe-commits]

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@@ -21,6 +25,7 @@ void a() {
   EVALF((2. + 3i) + (4. + 5i), 6. + 8i);
   EVALF((2. + 3i) - (4. + 5i), -2. - 2i);
   EVALF((2. + 3i) * (4. + 5i), -7. + 22i);
+  // div-precision-warning at +1 {{excess precision is requested but the target does not support excess precision which may result in observable differences in arithmetic behavior ,additional use of 'long double' were found but not diagnosed}}
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AaronBallman wrote:

Yeah, something like `additional uses where the requested higher precision cannot be honored were found but not diagnosed` maybe? Then we drop the type information entirely, which was what was causing my confusion.

https://github.com/llvm/llvm-project/pull/107397