[compiler-rt] [compiler-rt][ARM] Optimized integer -> FP conversions (PR #179928)

[Martin Storsjö via llvm-commits]

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@@ -207,4 +207,8 @@ LOCAL_LABEL(shiftdown):
 
 END_COMPILERRT_FUNCTION(__aeabi_l2d)
 
+#if defined(__MINGW32__)
+DEFINE_COMPILERRT_FUNCTION_ALIAS(__floatdidf, __i64tod)
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mstorsjo wrote:

This macro is the other way around; it should be `DEFINE_COMPILERRT_FUNCTION_ALIAS(newname, existingname)`.

If you remove the ifdef and attempt building, you would run into errors like these:
```
llvm-project/compiler-rt/lib/builtins/arm/floatdidf.S:211:92: error: redefinition of '__floatdidf'
.globl __floatdidf ; .def __floatdidf ; .scl 2 ; .type 32 ; .endef ; ; ; .set __floatdidf, __i64tod ;
                                                                                           ^
```

https://github.com/llvm/llvm-project/pull/179928