Source codes

1 files changed, 145 insertions, 0 deletions

diff --git a/Whisper/CPU/BufferAllocator.cpp b/Whisper/CPU/BufferAllocator.cpp
new file mode 100644
index 0000000..156382c
--- /dev/null
+++ b/Whisper/CPU/BufferAllocator.cpp
@@ -0,0 +1,145 @@
+#include <stdafx.h>
+#include "BufferAllocator.h"
+#include <immintrin.h>
+#include <ammintrin.h>
+using namespace CpuCompute;
+
+HRESULT BufferAllocator::create( size_t cb )
+{
+	CHECK( buffer.allocate( cb ) );
+	head = 0;
+	size = cb;
+	dbgMarkUninitializedMemory( buffer.pointer(), cb );
+	return S_OK;
+}
+
+namespace
+{
+	// Round up the integer by 32 bytes
+	__forceinline size_t roundUpAlloc( size_t cb )
+	{
+		const size_t mask = 31;
+		cb += mask;
+		// We require AVX1+FMA3 support, might as well use BMI1
+		return _andn_u64( mask, cb );
+	}
+}
+
+void* BufferAllocator::allocate( size_t cb, size_t align ) noexcept
+{
+	assert( align <= 32 );
+	cb = roundUpAlloc( cb );
+
+	uint8_t* pointer = buffer.pointer();
+	if( head + cb > size || nullptr == pointer )
+	{
+		logError( u8"BufferAllocator.allocate, not enough capacity" );
+		return nullptr;
+	}
+
+	void* const res = pointer + head;
+	head += cb;
+	assert( head <= size );
+	dbgMarkUninitializedMemory( res, cb );
+	return res;
+}
+
+namespace
+{
+	// 2 MB of memory, we hope the OS kernel will then be smart enough to give us large pages.
+	constexpr size_t virtualAllocGranularityExp2 = 21;
+
+	constexpr size_t virtualAllocGranularityMask = ( ( (size_t)1 ) << virtualAllocGranularityExp2 ) - 1;
+
+	// Round up the integer by 2 megabytes
+	__forceinline size_t roundUpVirtualAlloc( size_t cb )
+	{
+		const size_t mask = virtualAllocGranularityMask;
+		cb += mask;
+		return _andn_u64( mask, cb );
+	}
+}
+
+HRESULT VirtualAllocator::create( size_t cb )
+{
+	if( nullptr != pointer )
+		return HRESULT_FROM_WIN32( ERROR_ALREADY_INITIALIZED );
+	cb = roundUpVirtualAlloc( cb );
+	pointer = (uint8_t*)VirtualAlloc( NULL, cb, MEM_RESERVE, PAGE_READWRITE );
+	if( nullptr != pointer )
+	{
+		head = 0;
+		sizeAllocated = 0;
+		sizeVirtual = cb;
+		return S_OK;
+	}
+
+	const HRESULT hr = getLastHr();
+	logErrorHr( hr, u8"VirtualAlloc failed" );
+	return hr;
+}
+
+void* VirtualAllocator::allocate( size_t cb, size_t align ) noexcept
+{
+	assert( align <= 32 );
+	cb = roundUpAlloc( cb );
+
+	const size_t newHead = head + cb;
+	if( newHead <= sizeAllocated )
+	{
+		void* const res = pointer + head;
+		head = newHead;
+		dbgMarkUninitializedMemory( res, cb );
+		return res;
+	}
+
+	if( newHead <= sizeVirtual )
+	{
+		uint8_t* const ptrCommit = pointer + sizeAllocated;
+		const size_t cbCommit = roundUpVirtualAlloc( newHead ) - sizeAllocated;
+		void* const res = VirtualAlloc( ptrCommit, cbCommit, MEM_COMMIT, PAGE_READWRITE );
+		if( nullptr != res )
+		{
+			sizeAllocated += cbCommit;
+			assert( sizeAllocated <= sizeVirtual );
+			void* const res = pointer + head;
+			head = newHead;
+			dbgMarkUninitializedMemory( res, cb );
+			return res;
+		}
+
+		const HRESULT hr = getLastHr();
+		logErrorHr( hr, u8"VirtualAllocator.allocate, VirtualAlloc failed" );
+		return nullptr;
+	}
+
+	logError( u8"VirtualAllocator.allocate, not enough arena capacity" );
+	return nullptr;
+}
+
+VirtualAllocator::~VirtualAllocator()
+{
+	if( nullptr == pointer )
+		return;
+
+	if( VirtualFree( pointer, 0, MEM_RELEASE ) )
+	{
+		pointer = nullptr;
+		return;
+	}
+
+	const HRESULT hr = getLastHr();
+	logErrorHr( hr, u8"VirtualFree failed" );
+}
+
+#ifndef NDEBUG
+// Reusing Microsoft's magic numbers: https://asawicki.info/news_1292_magic_numbers_in_visual_c
+void CpuCompute::dbgMarkUninitializedMemory( void* pv, size_t cb )
+{
+	__stosb( (uint8_t*)pv, 0xCD, cb );
+}
+void CpuCompute::dbgMarkFreedMemory( void* pv, size_t cb )
+{
+	__stosd( (DWORD*)pv, 0xFEEEFEEEu, cb / 4 );
+}
+#endif
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