Fix for win32 build with gcc

[hyc]

Compiling with gcc on win32 is broken. This breaks gitian/depends builds of Monero.

[tevador]

I'm not sure why GCC defines a MSVC-specific macro. https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros?view=vs-2019#microsoft-specific-predefined-macros

A simpler fix would be:

#if defined(_MSC_VER) && defined(_M_IX86)

because the whole purpose of the asm function is to fix a bug in the MSVC sqrt function. It shouldn't be required for GCC.

In any case, please run randomx-tests to verify that all rounding modes are working correctly.

[hyc]

When building on Windows, all binaries are linked against the MSVC C runtime library, so if the bug is in the library as your comment indicates, then this is still needed even with gcc.

And I'd guess that particular macro was defined by the windows header files, not the compiler. Dunno though, didn't check.

Yeah, these are the only builtins

ubuntu@bbca643d0942:~$ i686-w64-mingw32-cpp -dM | grep 86
#define __DBL_DENORM_MIN__ ((double)4.94065645841246544176568792868221372e-324L)
#define __FLT_EVAL_METHOD_TS_18661_3__ 2
#define __FLT64X_EPSILON__ 1.08420217248550443400745280086994171e-19F64x
#define __i686 1
#define __DBL_MAX__ ((double)1.79769313486231570814527423731704357e+308L)
#define __i686__ 1
#define __FLT64_DENORM_MIN__ 4.94065645841246544176568792868221372e-324F64
#define __i386 1
#define _X86_ 1
#define __i386__ 1
#define __LDBL_EPSILON__ 1.08420217248550443400745280086994171e-19L
#define __FLT64_MAX__ 1.79769313486231570814527423731704357e+308F64
#define __FLT32X_MAX__ 1.79769313486231570814527423731704357e+308F32x
#define i386 1
#define __FLT32X_DENORM_MIN__ 4.94065645841246544176568792868221372e-324F32x
ubuntu@bbca643d0942:~$ 

[hyc]

64bit randomx-tests ran fine. I need to rebuild the 32bit test...

32bit test failed.

[67] FSQRT_R (decode)                         ... PASSED
[68] FSQRT_R RoundToNearest (execute)         ...
This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.
Assertion failed!

[tevador]

binaries are linked against the MSVC C runtime library

OK, then the assembly code is also needed. Let me know if the 32-bit tests pass, then I will merge it.

[hyc]

No looks like you're right. The tests with my assembly patch failed. Just #if'ing it out works though. Then the tests proceed until test 84, compiler hash tests. I presume these are meant to fail since there is no 32bit JIT compiler.

[tevador]

tests proceed until test 84

Then it's OK.

There was a bug in the tests. It should skip the compiler hash tests if JIT is not supported. Fixed in 7c405a7