IOAudioBlitterLibX86.cpp   [plain text]

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/*=============================================================================
	PCMBlitterLibX86.c
	
=============================================================================*/

#include <TargetConditionals.h>

#if __i386__ || __LP64__
#define _MM_MALLOC_H_INCLUDED 1	// we don't want this header
#include <xmmintrin.h>
#include "IOAudioBlitterLib.h"
#include <libkern/OSByteOrder.h>

#define kMaxFloat32 2147483520.0f
	// this is the biggest floating point number that result from a 32-bit int (bits are lost)
	// it's 2^31 - 128

static inline __m128i  byteswap16( __m128i v )
{
	//rotate each 16 bit quantity by 8 bits
	return _mm_or_si128( _mm_slli_epi16( v, 8 ), _mm_srli_epi16( v, 8 ) );
}

static inline __m128i  byteswap32( __m128i v )
{
	//rotate each 32 bit quantity by 16 bits
	// 0xB1 = 10110001 = 2,3,0,1
	v = _mm_shufflehi_epi16( _mm_shufflelo_epi16( v, 0xB1 ), 0xB1 );
	return byteswap16( v );
}


// ===================================================================================================
#pragma mark -
#pragma mark Float -> Int

void Float32ToNativeInt16_X86( const Float32 *src, SInt16 *dst, unsigned int numToConvert )
{
	const float *src0 = src;
	int16_t *dst0 = dst;
	unsigned int count = numToConvert;
	
	if (count >= 8) {
		// vector -- requires 8+ samples
		ROUNDMODE_NEG_INF
		const __m128 vround = (const __m128) { 0.5f, 0.5f, 0.5f, 0.5f };
		const __m128 vmin = (const __m128) { -32768.0f, -32768.0f, -32768.0f, -32768.0f };
		const __m128 vmax = (const __m128) { 32767.0f, 32767.0f, 32767.0f, 32767.0f  };
		const __m128 vscale = (const __m128) { 32768.0f, 32768.0f, 32768.0f, 32768.0f  };
		__m128 vf0, vf1;
		__m128i vi0, vi1, vpack0;
	
#define F32TOLE16 \
		vf0 = _mm_mul_ps(vf0, vscale);			\
		vf1 = _mm_mul_ps(vf1, vscale);			\
		vf0 = _mm_add_ps(vf0, vround);			\
		vf1 = _mm_add_ps(vf1, vround);			\
		vf0 = _mm_max_ps(vf0, vmin);			\
		vf1 = _mm_max_ps(vf1, vmin);			\
		vf0 = _mm_min_ps(vf0, vmax);			\
		vf1 = _mm_min_ps(vf1, vmax);			\
		vi0 = _mm_cvtps_epi32(vf0);			\
		vi1 = _mm_cvtps_epi32(vf1);			\
		vpack0 = _mm_packs_epi32(vi0, vi1);

		int falign = (uintptr_t)src & 0xF;
		int ialign = (uintptr_t)dst & 0xF;
	
		if (falign != 0 || ialign != 0) {
			// do one unaligned conversion
			vf0 = _mm_loadu_ps(src);
			vf1 = _mm_loadu_ps(src+4);
			F32TOLE16
			_mm_storeu_si128((__m128i *)dst, vpack0);
			
			// advance such that the destination ints are aligned
			unsigned int n = (16 - ialign) / 2;
			src += n;
			dst += n;
			count -= n;

			falign = (uintptr_t)src & 0xF;
			if (falign != 0) {
				// unaligned loads, aligned stores
				while (count >= 8) {
					vf0 = _mm_loadu_ps(src);
					vf1 = _mm_loadu_ps(src+4);
					F32TOLE16
					_mm_store_si128((__m128i *)dst, vpack0);
					src += 8;
					dst += 8;
					count -= 8;
				}
				goto VectorCleanup;
			}
		}
	
		// aligned loads, aligned stores
		while (count >= 8) {
			vf0 = _mm_load_ps(src);
			vf1 = _mm_load_ps(src+4);
			F32TOLE16
			_mm_store_si128((__m128i *)dst, vpack0);
			
			src += 8;
			dst += 8;
			count -= 8;
		}
VectorCleanup:
		if (count > 0) {
			// unaligned cleanup -- just do one unaligned vector at the end
			src = src0 + numToConvert - 8;
			dst = dst0 + numToConvert - 8;
			vf0 = _mm_loadu_ps(src);
			vf1 = _mm_loadu_ps(src+4);
			F32TOLE16
			_mm_storeu_si128((__m128i *)dst, vpack0);
		}
		RESTORE_ROUNDMODE
		return;
	}
	
	// scalar for small numbers of samples
	if (count > 0) {
		double scale = 2147483648.0, round = 32768.0, max32 = 2147483648.0 - 1.0 - 32768.0, min32 = 0.;
		ROUNDMODE_NEG_INF
		
		while (count-- > 0) {
			double f0 = *src++;
			f0 = f0 * scale + round;
			SInt32 i0 = FloatToInt(f0, min32, max32);
			i0 >>= 16;
			*dst++ = i0;
		}
		RESTORE_ROUNDMODE
	}
}

// ===================================================================================================

void Float32ToSwapInt16_X86( const Float32 *src, SInt16 *dst, unsigned int numToConvert )
{
	const float *src0 = src;
	int16_t *dst0 = dst;
	unsigned int count = numToConvert;
	
	if (count >= 8) {
		// vector -- requires 8+ samples
		ROUNDMODE_NEG_INF
		const __m128 vround = (const __m128) { 0.5f, 0.5f, 0.5f, 0.5f };
		const __m128 vmin = (const __m128) { -32768.0f, -32768.0f, -32768.0f, -32768.0f };
		const __m128 vmax = (const __m128) { 32767.0f, 32767.0f, 32767.0f, 32767.0f  };
		const __m128 vscale = (const __m128) { 32768.0f, 32768.0f, 32768.0f, 32768.0f  };
		__m128 vf0, vf1;
		__m128i vi0, vi1, vpack0;
	
#define F32TOBE16 \
		vf0 = _mm_mul_ps(vf0, vscale);			\
		vf1 = _mm_mul_ps(vf1, vscale);			\
		vf0 = _mm_add_ps(vf0, vround);			\
		vf1 = _mm_add_ps(vf1, vround);			\
		vf0 = _mm_max_ps(vf0, vmin);			\
		vf1 = _mm_max_ps(vf1, vmin);			\
		vf0 = _mm_min_ps(vf0, vmax);			\
		vf1 = _mm_min_ps(vf1, vmax);			\
		vi0 = _mm_cvtps_epi32(vf0);			\
		vi1 = _mm_cvtps_epi32(vf1);			\
		vpack0 = _mm_packs_epi32(vi0, vi1);		\
		vpack0 = byteswap16(vpack0);

		int falign = (uintptr_t)src & 0xF;
		int ialign = (uintptr_t)dst & 0xF;
	
		if (falign != 0 || ialign != 0) {
			// do one unaligned conversion
			vf0 = _mm_loadu_ps(src);
			vf1 = _mm_loadu_ps(src+4);
			F32TOBE16
			_mm_storeu_si128((__m128i *)dst, vpack0);

			// and advance such that the destination ints are aligned
			unsigned int n = (16 - ialign) / 2;
			src += n;
			dst += n;
			count -= n;

			falign = (uintptr_t)src & 0xF;
			if (falign != 0) {
				// unaligned loads, aligned stores
				while (count >= 8) {
					vf0 = _mm_loadu_ps(src);
					vf1 = _mm_loadu_ps(src+4);
					F32TOBE16
					_mm_store_si128((__m128i *)dst, vpack0);
					src += 8;
					dst += 8;
					count -= 8;
				}
				goto VectorCleanup;
			}
		}
	
		// aligned loads, aligned stores
		while (count >= 8) {
			vf0 = _mm_load_ps(src);
			vf1 = _mm_load_ps(src+4);
			F32TOBE16
			_mm_store_si128((__m128i *)dst, vpack0);
			
			src += 8;
			dst += 8;
			count -= 8;
		}
VectorCleanup:
		if (count > 0) {
			// unaligned cleanup -- just do one unaligned vector at the end
			src = src0 + numToConvert - 8;
			dst = dst0 + numToConvert - 8;
			vf0 = _mm_loadu_ps(src);
			vf1 = _mm_loadu_ps(src+4);
			F32TOBE16
			_mm_storeu_si128((__m128i *)dst, vpack0);
		}
		RESTORE_ROUNDMODE
		return;
	}
	
	// scalar for small numbers of samples
	if (count > 0) {
		double scale = 2147483648.0, round = 32768.0, max32 = 2147483648.0 - 1.0 - 32768.0, min32 = 0.;
		ROUNDMODE_NEG_INF
		
		while (count-- > 0) {
			double f0 = *src++;
			f0 = f0 * scale + round;
			SInt32 i0 = FloatToInt(f0, min32, max32);
			i0 >>= 16;
#if __ppc__			
			*dst++ = OSSwapInt16(i0);
#else
			*dst++ = i0;
#endif

		}
		RESTORE_ROUNDMODE
	}
}

// ===================================================================================================

void Float32ToNativeInt32_X86( const Float32 *src, SInt32 *dst, unsigned int numToConvert )
{
	const float *src0 = src;
	SInt32 *dst0 = dst;
	unsigned int count = numToConvert;
	
	if (count >= 4) {
		// vector -- requires 4+ samples
		ROUNDMODE_NEG_INF
		const __m128 vround = (const __m128) { 0.5f, 0.5f, 0.5f, 0.5f };
		const __m128 vmin = (const __m128) { -2147483648.0f, -2147483648.0f, -2147483648.0f, -2147483648.0f };
		const __m128 vmax = (const __m128) { kMaxFloat32, kMaxFloat32, kMaxFloat32, kMaxFloat32  };
		const __m128 vscale = (const __m128) { 2147483648.0f, 2147483648.0f, 2147483648.0f, 2147483648.0f  };
		__m128 vf0;
		__m128i vi0;
	
#define F32TOLE32(x) \
		vf##x = _mm_mul_ps(vf##x, vscale);			\
		vf##x = _mm_add_ps(vf##x, vround);			\
		vf##x = _mm_max_ps(vf##x, vmin);			\
		vf##x = _mm_min_ps(vf##x, vmax);			\
		vi##x = _mm_cvtps_epi32(vf##x);			\

		int falign = (uintptr_t)src & 0xF;
		int ialign = (uintptr_t)dst & 0xF;
	
		if (falign != 0 || ialign != 0) {
			// do one unaligned conversion
			vf0 = _mm_loadu_ps(src);
			F32TOLE32(0)
			_mm_storeu_si128((__m128i *)dst, vi0);
			
			// and advance such that the destination ints are aligned
			unsigned int n = (16 - ialign) / 4;
			src += n;
			dst += n;
			count -= n;

			falign = (uintptr_t)src & 0xF;
			if (falign != 0) {
				// unaligned loads, aligned stores
				while (count >= 4) {
					vf0 = _mm_loadu_ps(src);
					F32TOLE32(0)
					_mm_store_si128((__m128i *)dst, vi0);
					src += 4;
					dst += 4;
					count -= 4;
				}
				goto VectorCleanup;
			}
		}
	
		while (count >= 4) {
			vf0 = _mm_load_ps(src);
			F32TOLE32(0)
			_mm_store_si128((__m128i *)dst, vi0);
			
			src += 4;
			dst += 4;
			count -= 4;
		}
VectorCleanup:
		if (count > 0) {
			// unaligned cleanup -- just do one unaligned vector at the end
			src = src0 + numToConvert - 4;
			dst = dst0 + numToConvert - 4;
			vf0 = _mm_loadu_ps(src);
			F32TOLE32(0)
			_mm_storeu_si128((__m128i *)dst, vi0);
		}
		RESTORE_ROUNDMODE
		return;
	}
	
	// scalar for small numbers of samples
	if (count > 0) {
		double scale = 2147483648.0, round = 0.5, max32 = 2147483648.0 - 1.0 - 0.5, min32 = 0.;
		ROUNDMODE_NEG_INF
		
		while (count-- > 0) {
			double f0 = *src++;
			f0 = f0 * scale + round;
			SInt32 i0 = FloatToInt(f0, min32, max32);
			*dst++ = i0;
		}
		RESTORE_ROUNDMODE
	}
}

// ===================================================================================================

void Float32ToSwapInt32_X86( const Float32 *src, SInt32 *dst, unsigned int numToConvert )
{
	const float *src0 = src;
	SInt32 *dst0 = dst;
	unsigned int count = numToConvert;
	
	if (count >= 4) {
		// vector -- requires 4+ samples
		ROUNDMODE_NEG_INF
		const __m128 vround = (const __m128) { 0.5f, 0.5f, 0.5f, 0.5f };
		const __m128 vmin = (const __m128) { -2147483648.0f, -2147483648.0f, -2147483648.0f, -2147483648.0f };
		const __m128 vmax = (const __m128) { kMaxFloat32, kMaxFloat32, kMaxFloat32, kMaxFloat32  };
		const __m128 vscale = (const __m128) { 2147483648.0f, 2147483648.0f, 2147483648.0f, 2147483648.0f  };
		__m128 vf0;
		__m128i vi0;
	
#define F32TOBE32(x) \
		vf##x = _mm_mul_ps(vf##x, vscale);			\
		vf##x = _mm_add_ps(vf##x, vround);			\
		vf##x = _mm_max_ps(vf##x, vmin);			\
		vf##x = _mm_min_ps(vf##x, vmax);			\
		vi##x = _mm_cvtps_epi32(vf##x);			\
		vi##x = byteswap32(vi##x);

		int falign = (uintptr_t)src & 0xF;
		int ialign = (uintptr_t)dst & 0xF;
	
		if (falign != 0 || ialign != 0) {
			// do one unaligned conversion
			vf0 = _mm_loadu_ps(src);
			F32TOBE32(0)
			_mm_storeu_si128((__m128i *)dst, vi0);
			
			// and advance such that the destination ints are aligned
			unsigned int n = (16 - ialign) / 4;
			src += n;
			dst += n;
			count -= n;

			falign = (uintptr_t)src & 0xF;
			if (falign != 0) {
				// unaligned loads, aligned stores
				while (count >= 4) {
					vf0 = _mm_loadu_ps(src);
					F32TOBE32(0)
					_mm_store_si128((__m128i *)dst, vi0);
					src += 4;
					dst += 4;
					count -= 4;
				}
				goto VectorCleanup;
			}
		}
	
		while (count >= 4) {
			vf0 = _mm_load_ps(src);
			F32TOBE32(0)
			_mm_store_si128((__m128i *)dst, vi0);
			
			src += 4;
			dst += 4;
			count -= 4;
		}
VectorCleanup:
		if (count > 0) {
			// unaligned cleanup -- just do one unaligned vector at the end
			src = src0 + numToConvert - 4;
			dst = dst0 + numToConvert - 4;
			vf0 = _mm_loadu_ps(src);
			F32TOBE32(0)
			_mm_storeu_si128((__m128i *)dst, vi0);
		}
		RESTORE_ROUNDMODE
		return;
	}
	
	// scalar for small numbers of samples
	if (count > 0) {
		double scale = 2147483648.0, round = 0.5, max32 = 2147483648.0 - 1.0 - 0.5, min32 = 0.;
		ROUNDMODE_NEG_INF
		
		while (count-- > 0) {
			double f0 = *src++;
			f0 = f0 * scale + round;
			SInt32 i0 = FloatToInt(f0, min32, max32);
#if __ppc__			
			*dst++ = OSSwapInt32(i0);
#else
			*dst++ =  i0;
#endif

		}
		RESTORE_ROUNDMODE
	}
}

// ===================================================================================================

// ~14 instructions
static inline __m128i Pack32ToLE24(__m128i val, __m128i mask)
{
	__m128i store;
	val = _mm_srli_si128(val, 1);
	store = _mm_and_si128(val, mask);

	val = _mm_srli_si128(val, 1);
	mask = _mm_slli_si128(mask, 3);
	store = _mm_or_si128(store, _mm_and_si128(val, mask));

	val = _mm_srli_si128(val, 1);
	mask = _mm_slli_si128(mask, 3);
	store = _mm_or_si128(store, _mm_and_si128(val, mask));

	val = _mm_srli_si128(val, 1);
	mask = _mm_slli_si128(mask, 3);
	store = _mm_or_si128(store, _mm_and_si128(val, mask));
	return store;
}

// marginally faster than scalar
void Float32ToNativeInt24_X86( const Float32 *src, UInt8 *dst, unsigned int numToConvert )
{
	const Float32 *src0 = src;
	UInt8 *dst0 = dst;
	unsigned int count = numToConvert;
	
	if (count >= 6) {
		// vector -- requires 6+ samples
		ROUNDMODE_NEG_INF
		const __m128 vround = (const __m128) { 0.5f, 0.5f, 0.5f, 0.5f };
		const __m128 vmin = (const __m128) { -2147483648.0f, -2147483648.0f, -2147483648.0f, -2147483648.0f };
		const __m128 vmax = (const __m128) { kMaxFloat32, kMaxFloat32, kMaxFloat32, kMaxFloat32  };
		const __m128 vscale = (const __m128) { 2147483648.0f, 2147483648.0f, 2147483648.0f, 2147483648.0f  };
		__m128i mask = _mm_setr_epi32(0x00FFFFFF, 0, 0, 0);
			// it is actually cheaper to copy and shift this mask on the fly than to have 4 of them

		__m128i store;
		union {
			UInt32 i[4];
			__m128i v;
		} u;

		__m128 vf0;
		__m128i vi0;

		int falign = (uintptr_t)src & 0xF;
	
		if (falign != 0) {
			// do one unaligned conversion
			vf0 = _mm_loadu_ps(src);
			F32TOLE32(0)
			store = Pack32ToLE24(vi0, mask);
			_mm_storeu_si128((__m128i *)dst, store);

			// and advance such that the source floats are aligned
			unsigned int n = (16 - falign) / 4;
			src += n;
			dst += 3*n;	// bytes
			count -= n;
		}
	
		while (count >= 6) {
			vf0 = _mm_load_ps(src);
			F32TOLE32(0)
			store = Pack32ToLE24(vi0, mask);
			_mm_storeu_si128((__m128i *)dst, store);	// destination always unaligned
			
			src += 4;
			dst += 12;	// bytes
			count -= 4;
		}
		
		
		if (count >= 4) {
			vf0 = _mm_load_ps(src);
			F32TOLE32(0)
			u.v = Pack32ToLE24(vi0, mask);
			((UInt32 *)dst)[0] = u.i[0];
			((UInt32 *)dst)[1] = u.i[1];
			((UInt32 *)dst)[2] = u.i[2];
			
			src += 4;
			dst += 12;	// bytes
			count -= 4;
		}

		if (count > 0) {
			// unaligned cleanup -- just do one unaligned vector at the end
			src = src0 + numToConvert - 4;
			dst = dst0 + 3*numToConvert - 12;
			vf0 = _mm_loadu_ps(src);
			F32TOLE32(0)
			u.v = Pack32ToLE24(vi0, mask);
			((UInt32 *)dst)[0] = u.i[0];
			((UInt32 *)dst)[1] = u.i[1];
			((UInt32 *)dst)[2] = u.i[2];
		}
		RESTORE_ROUNDMODE
		return;
	}
	
	// scalar for small numbers of samples
	if (count > 0) {
		double scale = 2147483648.0, round = 0.5, max32 = 2147483648.0 - 1.0 - 0.5, min32 = 0.;
		ROUNDMODE_NEG_INF
		
		while (count-- > 0) {
			double f0 = *src++;
			f0 = f0 * scale + round;
			UInt32 i0 = FloatToInt(f0, min32, max32);
			dst[0] = (UInt8)(i0 >> 8);
			dst[1] = (UInt8)(i0 >> 16);
			dst[2] = (UInt8)(i0 >> 24);
			dst += 3;
		}
		RESTORE_ROUNDMODE
	}
}


// ===================================================================================================
#pragma mark -
#pragma mark Int -> Float

void NativeInt16ToFloat32_X86( const SInt16 *src, Float32 *dst, unsigned int numToConvert )
{
	const SInt16 *src0 = src;
	Float32 *dst0 = dst;
	unsigned int count = numToConvert;

	if (count >= 8) {
		// vector -- requires 8+ samples
		// convert the 16-bit words to the high word of 32-bit values
#define LEI16TOF32(x, y) \
	vi##x = _mm_unpacklo_epi16(zero, vpack##x); \
	vi##y = _mm_unpackhi_epi16(zero, vpack##x); \
	vf##x = _mm_cvtepi32_ps(vi##x); \
	vf##y = _mm_cvtepi32_ps(vi##y); \
	vf##x = _mm_mul_ps(vf##x, vscale); \
	vf##y = _mm_mul_ps(vf##y, vscale);
		
		const __m128 vscale = (const __m128) { 1.0/2147483648.0f, 1.0/2147483648.0f, 1.0/2147483648.0f, 1.0/2147483648.0f  };
		const __m128i zero = _mm_setzero_si128();
		__m128 vf0, vf1;
		__m128i vi0, vi1, vpack0;

		int ialign = (uintptr_t)src & 0xF;
		int falign = (uintptr_t)dst & 0xF;
	
		if (falign != 0 || ialign != 0) {
			// do one unaligned conversion
			vpack0 = _mm_loadu_si128((__m128i const *)src);
			LEI16TOF32(0, 1)
			_mm_storeu_ps(dst, vf0);
			_mm_storeu_ps(dst+4, vf1);
			
			// and advance such that the destination floats are aligned
			unsigned int n = (16 - falign) / 4;
			src += n;
			dst += n;
			count -= n;

			ialign = (uintptr_t)src & 0xF;
			if (ialign != 0) {
				// unaligned loads, aligned stores
				while (count >= 8) {
					vpack0 = _mm_loadu_si128((__m128i const *)src);
					LEI16TOF32(0, 1)
					_mm_store_ps(dst, vf0);
					_mm_store_ps(dst+4, vf1);
					src += 8;
					dst += 8;
					count -= 8;
				}
				goto VectorCleanup;
			}
		}
	
		// aligned loads, aligned stores
		while (count >= 8) {
			vpack0 = _mm_load_si128((__m128i const *)src);
			LEI16TOF32(0, 1)
			_mm_store_ps(dst, vf0);
			_mm_store_ps(dst+4, vf1);
			src += 8;
			dst += 8;
			count -= 8;
		}
		
VectorCleanup:
		if (count > 0) {
			// unaligned cleanup -- just do one unaligned vector at the end
			src = src0 + numToConvert - 8;
			dst = dst0 + numToConvert - 8;
			vpack0 = _mm_loadu_si128((__m128i const *)src);
			LEI16TOF32(0, 1)
			_mm_storeu_ps(dst, vf0);
			_mm_storeu_ps(dst+4, vf1);
		}
		return;
	}
	// scalar for small numbers of samples
	if (count > 0) {
		double scale = 1./32768.f;
		while (count-- > 0) {
			SInt16 i = *src++;
			double f = (double)i * scale;
			*dst++ = f;
		}
	}
}

// ===================================================================================================

void SwapInt16ToFloat32_X86( const SInt16 *src, Float32 *dst, unsigned int numToConvert )
{
	const SInt16 *src0 = src;
	Float32 *dst0 = dst;
	unsigned int count = numToConvert;

	if (count >= 8) {
		// vector -- requires 8+ samples
		// convert the 16-bit words to the high word of 32-bit values
#define BEI16TOF32 \
	vpack0 = byteswap16(vpack0); \
	vi0 = _mm_unpacklo_epi16(zero, vpack0); \
	vi1 = _mm_unpackhi_epi16(zero, vpack0); \
	vf0 = _mm_cvtepi32_ps(vi0); \
	vf1 = _mm_cvtepi32_ps(vi1); \
	vf0 = _mm_mul_ps(vf0, vscale); \
	vf1 = _mm_mul_ps(vf1, vscale);
		
		const __m128 vscale = (const __m128) { 1.0/2147483648.0f, 1.0/2147483648.0f, 1.0/2147483648.0f, 1.0/2147483648.0f  };
		const __m128i zero = _mm_setzero_si128();
		__m128 vf0, vf1;
		__m128i vi0, vi1, vpack0;

		int ialign = (uintptr_t)src & 0xF;
		int falign = (uintptr_t)dst & 0xF;
	
		if (falign != 0 || ialign != 0) {
			// do one unaligned conversion
			vpack0 = _mm_loadu_si128((__m128i const *)src);
			BEI16TOF32
			_mm_storeu_ps(dst, vf0);
			_mm_storeu_ps(dst+4, vf1);

			// and advance such that the destination floats are aligned
			unsigned int n = (16 - falign) / 4;
			src += n;
			dst += n;
			count -= n;

			ialign = (uintptr_t)src & 0xF;
			if (ialign != 0) {
				// unaligned loads, aligned stores
				while (count >= 8) {
					vpack0 = _mm_loadu_si128((__m128i const *)src);
					BEI16TOF32
					_mm_store_ps(dst, vf0);
					_mm_store_ps(dst+4, vf1);
					src += 8;
					dst += 8;
					count -= 8;
				}
				goto VectorCleanup;
			}
		}
	
		// aligned loads, aligned stores
		while (count >= 8) {
			vpack0 = _mm_load_si128((__m128i const *)src);
			BEI16TOF32
			_mm_store_ps(dst, vf0);
			_mm_store_ps(dst+4, vf1);
			src += 8;
			dst += 8;
			count -= 8;
		}
		
VectorCleanup:
		if (count > 0) {
			// unaligned cleanup -- just do one unaligned vector at the end
			src = src0 + numToConvert - 8;
			dst = dst0 + numToConvert - 8;
			vpack0 = _mm_loadu_si128((__m128i const *)src);
			BEI16TOF32
			_mm_storeu_ps(dst, vf0);
			_mm_storeu_ps(dst+4, vf1);
		}
		return;
	}
	// scalar for small numbers of samples
	if (count > 0) {
		double scale = 1./32768.f;
		while (count-- > 0) {
			SInt16 i = *src++;
#if __ppc__
			i = OSSwapInt16(i);
#endif
			double f = (double)i * scale;
			*dst++ = f;
		}
	}
}

// ===================================================================================================

void NativeInt32ToFloat32_X86( const SInt32 *src, Float32 *dst, unsigned int numToConvert )
{
	const SInt32 *src0 = src;
	Float32 *dst0 = dst;
	unsigned int count = numToConvert;

	if (count >= 4) {
		// vector -- requires 4+ samples
#define LEI32TOF32(x) \
	vf##x = _mm_cvtepi32_ps(vi##x); \
	vf##x = _mm_mul_ps(vf##x, vscale); \
		
		const __m128 vscale = (const __m128) { 1.0/2147483648.0f, 1.0/2147483648.0f, 1.0/2147483648.0f, 1.0/2147483648.0f  };
		__m128 vf0;
		__m128i vi0;

		int ialign = (uintptr_t)src & 0xF;
		int falign = (uintptr_t)dst & 0xF;
	
		if (falign != 0 || ialign != 0) {
			// do one unaligned conversion
			vi0 = _mm_loadu_si128((__m128i const *)src);
			LEI32TOF32(0)
			_mm_storeu_ps(dst, vf0);
			
			// and advance such that the destination floats are aligned
			unsigned int n = (16 - falign) / 4;
			src += n;
			dst += n;
			count -= n;

			ialign = (uintptr_t)src & 0xF;
			if (ialign != 0) {
				// unaligned loads, aligned stores
				while (count >= 4) {
					vi0 = _mm_loadu_si128((__m128i const *)src);
					LEI32TOF32(0)
					_mm_store_ps(dst, vf0);
					src += 4;
					dst += 4;
					count -= 4;
				}
				goto VectorCleanup;
			}
		}
	
		// aligned loads, aligned stores
		while (count >= 4) {
			vi0 = _mm_load_si128((__m128i const *)src);
			LEI32TOF32(0)
			_mm_store_ps(dst, vf0);
			src += 4;
			dst += 4;
			count -= 4;
		}
		
VectorCleanup:
		if (count > 0) {
			// unaligned cleanup -- just do one unaligned vector at the end
			src = src0 + numToConvert - 4;
			dst = dst0 + numToConvert - 4;
			vi0 = _mm_loadu_si128((__m128i const *)src);
			LEI32TOF32(0)
			_mm_storeu_ps(dst, vf0);
		}
		return;
	}
	// scalar for small numbers of samples
	if (count > 0) {
		double scale = 1./2147483648.0f;
		while (count-- > 0) {
			SInt32 i = *src++;
			double f = (double)i * scale;
			*dst++ = f;
		}
	}
}

// ===================================================================================================

void SwapInt32ToFloat32_X86( const SInt32 *src, Float32 *dst, unsigned int numToConvert )
{
	const SInt32 *src0 = src;
	Float32 *dst0 = dst;
	unsigned int count = numToConvert;

	if (count >= 4) {
		// vector -- requires 4+ samples
#define BEI32TOF32(x) \
	vi##x = byteswap32(vi##x); \
	vf##x = _mm_cvtepi32_ps(vi##x); \
	vf##x = _mm_mul_ps(vf##x, vscale); \
		
		const __m128 vscale = (const __m128) { 1.0/2147483648.0f, 1.0/2147483648.0f, 1.0/2147483648.0f, 1.0/2147483648.0f  };
		__m128 vf0;
		__m128i vi0;

		int ialign = (uintptr_t)src & 0xF;
		int falign = (uintptr_t)dst & 0xF;
	
		if (falign != 0 || ialign != 0) {
			// do one unaligned conversion
			vi0 = _mm_loadu_si128((__m128i const *)src);
			BEI32TOF32(0)
			_mm_storeu_ps(dst, vf0);
			
			// and advance such that the destination floats are aligned
			unsigned int n = (16 - falign) / 4;
			src += n;
			dst += n;
			count -= n;

			ialign = (uintptr_t)src & 0xF;
			if (ialign != 0) {
				// unaligned loads, aligned stores
				while (count >= 4) {
					vi0 = _mm_loadu_si128((__m128i const *)src);
					BEI32TOF32(0)
					_mm_store_ps(dst, vf0);
					src += 4;
					dst += 4;
					count -= 4;
				}
				goto VectorCleanup;
			}
		}
	
		// aligned loads, aligned stores
		while (count >= 4) {
			vi0 = _mm_load_si128((__m128i const *)src);
			BEI32TOF32(0)
			_mm_store_ps(dst, vf0);
			src += 4;
			dst += 4;
			count -= 4;
		}
		
VectorCleanup:
		if (count > 0) {
			// unaligned cleanup -- just do one unaligned vector at the end
			src = src0 + numToConvert - 4;
			dst = dst0 + numToConvert - 4;
			vi0 = _mm_loadu_si128((__m128i const *)src);
			BEI32TOF32(0)
			_mm_storeu_ps(dst, vf0);
		}
		return;
	}
	// scalar for small numbers of samples
	if (count > 0) {
		double scale = 1./2147483648.0f;
		while (count-- > 0) {
			SInt32 i = *src++;
#if __ppc__
			i = OSSwapInt32(i);
#endif

			double f = (double)i * scale;
			*dst++ = f;
		}
	}
}


#endif // __i386__