[llvm] [X86][NFC] - Add sitofp and fptosi tests for x87 mode (PR #136860)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,272 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; NOTE: Fast Isel is not added because it does not support x87 stores.
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RKSimon wrote:

rename[isel-sint-to-fp-x87.ll ?

https://github.com/llvm/llvm-project/pull/136860