93 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			93 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|  | 
 | ||
|  | #ifndef BT_CPU_UTILITY_H
 | ||
|  | #define BT_CPU_UTILITY_H
 | ||
|  | 
 | ||
|  | #include "LinearMath/btScalar.h"
 | ||
|  | 
 | ||
|  | #include <string.h>//memset
 | ||
|  | #ifdef  USE_SIMD
 | ||
|  | #include <emmintrin.h>
 | ||
|  | #ifdef BT_ALLOW_SSE4
 | ||
|  | #include <intrin.h>
 | ||
|  | #endif //BT_ALLOW_SSE4
 | ||
|  | #endif //USE_SIMD
 | ||
|  | 
 | ||
|  | #if defined BT_USE_NEON
 | ||
|  | #define ARM_NEON_GCC_COMPATIBILITY  1
 | ||
|  | #include <arm_neon.h>
 | ||
|  | #include <sys/types.h>
 | ||
|  | #include <sys/sysctl.h> //for sysctlbyname
 | ||
|  | #endif //BT_USE_NEON
 | ||
|  | 
 | ||
|  | ///Rudimentary btCpuFeatureUtility for CPU features: only report the features that Bullet actually uses (SSE4/FMA3, NEON_HPFP)
 | ||
|  | ///We assume SSE2 in case BT_USE_SSE2 is defined in LinearMath/btScalar.h
 | ||
|  | class btCpuFeatureUtility | ||
|  | { | ||
|  | public: | ||
|  | 	enum btCpuFeature | ||
|  | 	{ | ||
|  | 		CPU_FEATURE_FMA3=1, | ||
|  | 		CPU_FEATURE_SSE4_1=2, | ||
|  | 		CPU_FEATURE_NEON_HPFP=4 | ||
|  | 	}; | ||
|  | 
 | ||
|  | 	static int getCpuFeatures() | ||
|  | 	{ | ||
|  | 
 | ||
|  | 		static int capabilities = 0; | ||
|  | 		static bool testedCapabilities = false; | ||
|  | 		if (0 != testedCapabilities) | ||
|  | 		{ | ||
|  | 			return capabilities; | ||
|  | 		} | ||
|  | 
 | ||
|  | #ifdef BT_USE_NEON
 | ||
|  | 		{ | ||
|  | 			uint32_t hasFeature = 0; | ||
|  | 			size_t featureSize = sizeof(hasFeature); | ||
|  | 			int err = sysctlbyname("hw.optional.neon_hpfp", &hasFeature, &featureSize, NULL, 0); | ||
|  | 			if (0 == err && hasFeature) | ||
|  | 				capabilities |= CPU_FEATURE_NEON_HPFP; | ||
|  | 		} | ||
|  | #endif //BT_USE_NEON
 | ||
|  | 
 | ||
|  | #ifdef  BT_ALLOW_SSE4
 | ||
|  | 		{ | ||
|  | 			int					cpuInfo[4]; | ||
|  | 			memset(cpuInfo, 0, sizeof(cpuInfo)); | ||
|  | 			unsigned long long	sseExt = 0; | ||
|  | 			__cpuid(cpuInfo, 1); | ||
|  | 			 | ||
|  | 			bool osUsesXSAVE_XRSTORE = cpuInfo[2] & (1 << 27) || false; | ||
|  | 			bool cpuAVXSuport = cpuInfo[2] & (1 << 28) || false; | ||
|  | 
 | ||
|  | 			if (osUsesXSAVE_XRSTORE && cpuAVXSuport) | ||
|  | 			{ | ||
|  | 				sseExt = _xgetbv(0); | ||
|  | 			} | ||
|  | 			const int OSXSAVEFlag = (1UL << 27); | ||
|  | 			const int AVXFlag = ((1UL << 28) | OSXSAVEFlag); | ||
|  | 			const int FMAFlag = ((1UL << 12) | AVXFlag | OSXSAVEFlag); | ||
|  | 			if ((cpuInfo[2] & FMAFlag) == FMAFlag && (sseExt & 6) == 6) | ||
|  | 			{ | ||
|  | 				capabilities |= btCpuFeatureUtility::CPU_FEATURE_FMA3; | ||
|  | 			} | ||
|  | 
 | ||
|  | 			const int SSE41Flag = (1 << 19); | ||
|  | 			if (cpuInfo[2] & SSE41Flag) | ||
|  | 			{ | ||
|  | 				capabilities |= btCpuFeatureUtility::CPU_FEATURE_SSE4_1; | ||
|  | 			} | ||
|  | 		} | ||
|  | #endif//BT_ALLOW_SSE4
 | ||
|  | 
 | ||
|  | 		testedCapabilities = true; | ||
|  | 		return capabilities; | ||
|  | 	} | ||
|  | 
 | ||
|  | 
 | ||
|  | }; | ||
|  | 
 | ||
|  | 
 | ||
|  | #endif //BT_CPU_UTILITY_H
 |