12/23/2023 0 Comments Sse2 windows cmake![]() ![]() You can download libfdk-aac separately here ( O=D) and put the dll-file in the same map as 'ffmpeg.exe', or in any map listed in the %PATH%-variable. Starting with ffmpeg-6.c71 from 04-05-2023 this is no longer the case. My FFmpeg binaries are compiled with -enable-libfdk-aac, but they don't contain the actual code because of an incompatible license. In fact, it was literally my first encounter with Linux (Cygwin) Bash! But after my first attempts () I forked Roger Pack's cross-compilation-script () and the rest is history. With the help of a third-party cryptography-library (OpenSSL, GnuTLS, or MbedTLS) I could solve that issue. This was the main reason I wanted to see if I could compile my own FFmpeg binaries. Windows XP doesn't support TLS 1.2 and the latest compatible FFmpeg binary back then couldn't open TLS 1.2 encrypted https-urls either, which a lot of websites started using. ![]() This all began end 2016 when (as far as I could tell) no one was willing to create WinXP- and old-CPU compatible FFmpeg binaries anymore. MSVC fails even at simple detection phase… this is not surprising, though: MSVC was never all that good as pure C++ compiler, it’s strength lies with tight integration with other Visual Studio tools… some of which are superb and leave anything you may find on other platforms in the dust.On Zeranoe ()'s forum I had a topic where once every 4 months I would post new FFmpeg binaries that are Windows XP compatible and will work on old CPUs without SSE2 instruction sets (like my own AMD Athlon XP 3200+).īecause Zeranoe took down his forum not so long ago I thought I'd create a topic here on Doom9 in the hope some of you might still find these binaries useful. There you can easily write different versions of functions and compiler will do all the right things: stop compilation if you use improper intrinsic, pick the right version if you support more than one CPU, etc.Īs you can see behavior MSVC exhibits is not only not needed, it’s obviously harmful: if you are planning to write two versions of the code then you would like to be sure that the one which is not supposed to use SSE4… doesn’t use it. The right function would be picked automatically. People need this explained because it’s surprising. ![]() ![]() (“The custom did not pass any flags that would enable SSE4 instructions.”) Please interpret the remark in the spirit it was intended. ¹ As commenter Danielix Klimax noted, there is no actual /arch:SSE4 option. When you detect an SSE4 system, you can explicitly call the SSE4 code paths. The compiler won’t generate any SSE4 instructions on its own, so your code is safe on SSE2 systems. The reason SSE4 intrinsics are still allowed even in SSE2 mode is that you might have identified some performance-sensitive operations and written two versions of the code, one that uses SSE2 intrinsics, and another that uses SSE4 intrinsics, choosing between the two at runtime based on a processor capability check. If they had run it on a a CPU that supported SSE2 but not SSE4, it would have crashed. The customer happened to test their program on a CPU that supported SSE4, so the instruction worked. I guess the option could be more accurately (and verbosely) named “Enable automatic use of instructions available with SSE2-enabled CPUs.” Because what this controls is whether the compiler will use those instructions of its own volition. But if you invoke it explicitly, then you get what you wrote. The /arch:SSE2 flag tells the compiler not to use any instructions beyond SSE2 in its own code generation, say during autovectorization or optimized memcpy. You explicitly requested an SSE4 instruction, so the compiler honored your request. Did the compiler convert the _mm_insert_epi32() into an equivalent series of SSE2 instructions? To the customer’s surprise, this code not only compiled, it even ran! The customer wanted to know what is happening. The _mm_insert_epi32() intrinsic maps to the PINSRD instruction, which is an SSE4 instruction, not SSE2. A customer passed the /arch:SSE2 flag to the Microsoft Visual C++ compiler, which means “Enable use of instructions available with SSE2-enabled CPUs.” In particular, the customer did not pass the /arch:SSE4 flag,¹ so they did not enable the use of SSE4 instructions. ![]()
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