[MSVC] Wrong define checked when building for 64bit with Visual Studio

[MessyHack]

Should check defined(_M_X64) not defined(_M_X86) when building with MSVC.

_M_X86 is only defined under MSVC 32Bit
_M_X64 is only defined under MSVC 64Bit

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[MessyHack]

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[Cyan4973]

Reasoning looks good,

I'm curious if it impacts performance in any way on Visual x64.

[MessyHack]

Reasoning looks good,

I'm curious if it impacts performance in any way on Visual x64.

There's a slight perf gain when building with MSVC and targeting AVX2. (Using current VS 2022 preview)
I should double check the SSE behavior

When targeting AVX2, MSVC will use bzhi (bmi2 instruction). This only happens when targeting AVX2.

[MessyHack]

Reasoning looks good,
I'm curious if it impacts performance in any way on Visual x64.

There's a slight perf gain when building with MSVC and targeting AVX2. (Using current VS 2022 preview) I should double check the SSE behavior

When targeting AVX2, MSVC will use bzhi (bmi2 instruction). This only happens when targeting AVX2.

SSE seems ok; but not really that different.

(before change; SSE)
3#Lorem ipsum : 10000000 -> 2983345 (x3.352), 337.1 MB/s 1181.9 MB/s
vs
(after change; SSE
3#Lorem ipsum : 10000000 -> 2983345 (x3.352), 339.4 MB/s 1192.0 MB/s

[Cyan4973]

When targeting AVX2, MSVC will use bzhi (bmi2 instruction). This only happens when targeting AVX2.

I thinks that's the main goal.
We observed that bmi2 gives a small but solid performance gain.
Enabling that should be beneficial.