From 7aa4b53422e9519e7b3c8fbc570cf1e669affbdd Mon Sep 17 00:00:00 2001
From: "Unknown W. Brackets" <checkins@unknownbrackets.org>
Date: Sun, 14 Feb 2021 09:38:23 -0800
Subject: [PATCH] Common: Fix AVX check on mingw/lower targets.

---
 Common/CPUDetect.cpp | 35 +++++++++++++++++++++--------------
 1 file changed, 21 insertions(+), 14 deletions(-)

diff --git a/Common/CPUDetect.cpp b/Common/CPUDetect.cpp
index 70c640eee7..04780f5f7f 100644
--- a/Common/CPUDetect.cpp
+++ b/Common/CPUDetect.cpp
@@ -26,6 +26,7 @@
 #include <sys/sysctl.h>
 #endif
 
+#include <cstdint>
 #include <memory.h>
 #include <set>
 
@@ -34,10 +35,9 @@
 #include "Common/File/FileUtil.h"
 #include "Common/StringUtils.h"
 
-#if defined(_WIN32) && !defined(__MINGW32__)
+#if defined(_WIN32)
+#include "Common/CommonWindows.h"
 
-#define WIN32_LEAN_AND_MEAN
-#include <Windows.h>
 #define _interlockedbittestandset workaround_ms_header_bug_platform_sdk6_set
 #define _interlockedbittestandreset workaround_ms_header_bug_platform_sdk6_reset
 #define _interlockedbittestandset64 workaround_ms_header_bug_platform_sdk6_set64
@@ -55,21 +55,27 @@ void do_cpuid(u32 regs[4], u32 cpuid_leaf) {
 	__cpuid((int *)regs, cpuid_leaf);
 }
 
+#ifdef __MINGW32__
+static uint64_t do_xgetbv(unsigned int index) {
+	unsigned int eax, edx;
+	// This is xgetbv directly, so we can avoid compilers warning we need runtime checks.
+	asm(".byte 0x0f, 0x01, 0xd0" : "=a"(eax), "=d"(edx) : "c"(index));
+	return ((uint64_t)edx << 32) | eax;
+}
+#else
+#define do_xgetbv _xgetbv
+#endif
+
 #else  // _WIN32
 
 #ifdef _M_SSE
 #include <emmintrin.h>
 
-#define _XCR_XFEATURE_ENABLED_MASK 0
-static unsigned long long _xgetbv(unsigned int index)
-{
+static uint64_t do_xgetbv(unsigned int index) {
 	unsigned int eax, edx;
 	__asm__ __volatile__("xgetbv" : "=a"(eax), "=d"(edx) : "c"(index));
-	return ((unsigned long long)edx << 32) | eax;
+	return ((uint64_t)edx << 32) | eax;
 }
-
-#else
-#define _XCR_XFEATURE_ENABLED_MASK 0
 #endif  // _M_SSE
 
 #if !defined(MIPS)
@@ -98,6 +104,9 @@ void do_cpuid(u32 regs[4], u32 cpuid_leaf)
 
 #endif  // !win32
 
+#ifndef _XCR_XFEATURE_ENABLED_MASK
+#define _XCR_XFEATURE_ENABLED_MASK 0
+#endif
 
 CPUInfo cpu_info;
 
@@ -215,10 +224,8 @@ void CPUInfo::Detect() {
 		//  - Is the XSAVE bit set in CPUID? ( >>26)
 		//  - Is the OSXSAVE bit set in CPUID? ( >>27)
 		//  - XGETBV result has the XCR bit set.
-		if (((cpu_id[2] >> 28) & 1) && ((cpu_id[2] >> 27) & 1) && ((cpu_id[2] >> 26) & 1))
-		{
-			if ((_xgetbv(_XCR_XFEATURE_ENABLED_MASK) & 0x6) == 0x6)
-			{
+		if (((cpu_id[2] >> 28) & 1) && ((cpu_id[2] >> 27) & 1) && ((cpu_id[2] >> 26) & 1)) {
+			if ((do_xgetbv(_XCR_XFEATURE_ENABLED_MASK) & 0x6) == 0x6) {
 				bAVX = true;
 				if ((cpu_id[2] >> 12) & 1)
 					bFMA3 = true;