[compiler-rt] [builtins] Convert more int to fp functions to use common implementation (PR #67540)

[Rainer Orth via llvm-commits]

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@@ -16,6 +16,10 @@
 #include "fp_lib.h"
 #include "int_lib.h"
 
+#define SRC_U128
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rorth wrote:

This works indeed.  `floattitf.c` needs the same patch.  It's unfortunate, however, that `int_to_fp.h`isn't more robust, unconditionally using types whose existance isn't guaranteed everywhere.

https://github.com/llvm/llvm-project/pull/67540