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/*++
Copyright (c) 1988-1992 Microsoft Corporation
Module Name:
Align.h
Abstract:
BUGBUG
Author:
John Rogers (JohnRo) 15-May-1991
Environment:
This code assumes that sizeof(DWORD) >= sizeof(LPVOID).
Revision History:
15-May-1991 JohnRo
Created align.h for NT/LAN from OS/2 1.2 HPFS pbmacros.h.
19-Jun-1991 JohnRo
Make sure pointer-to-wider-then-byte doesn't get messed up.
10-Jul-1991 JohnRo
Added ALIGN_BYTE and ALIGN_CHAR for completeness.
21-Aug-1991 CliffV
Fix ROUND_DOWN_* to include ~
03-Dec-1991 JohnRo
Worst-case on MIPS is 8-byte alignment.
Added COUNT_IS_ALIGNED() and POINTER_IS_ALIGNED() macros.
26-Jun-1992 JohnRo
RAID 9933: ALIGN_WORST should be 8 for x86 builds.
--*/
#ifndef _ALIGN_
#define _ALIGN_
// BOOL
// COUNT_IS_ALIGNED(
// IN DWORD Count,
// IN DWORD Pow2 // undefined if this isn't a power of 2.
// );
//
#define COUNT_IS_ALIGNED(Count,Pow2) \
( ( ( (Count) & (((Pow2)-1)) ) == 0) ? TRUE : FALSE )
// BOOL
// POINTER_IS_ALIGNED(
// IN LPVOID Ptr,
// IN DWORD Pow2 // undefined if this isn't a power of 2.
// );
//
#define POINTER_IS_ALIGNED(Ptr,Pow2) \
( ( ( ((DWORD)(Ptr)) & (((Pow2)-1)) ) == 0) ? TRUE : FALSE )
#define ROUND_DOWN_COUNT(Count,Pow2) \
( (Count) & (~((Pow2)-1)) )
#define ROUND_DOWN_POINTER(Ptr,Pow2) \
( (LPVOID) ROUND_DOWN_COUNT( ((DWORD)(Ptr)), (Pow2) ) )
// If Count is not already aligned, then
// round Count up to an even multiple of "Pow2". "Pow2" must be a power of 2.
//
// DWORD
// ROUND_UP_COUNT(
// IN DWORD Count,
// IN DWORD Pow2
// );
#define ROUND_UP_COUNT(Count,Pow2) \
( ((Count)+(Pow2)-1) & (~((Pow2)-1)) )
// LPVOID
// ROUND_UP_POINTER(
// IN LPVOID Ptr,
// IN DWORD Pow2
// );
// If Ptr is not already aligned, then round it up until it is.
#define ROUND_UP_POINTER(Ptr,Pow2) \
( (LPVOID) ( (((DWORD)(Ptr))+(Pow2)-1) & (~((Pow2)-1)) ) )
// Usage: myPtr = ROUND_UP_POINTER(unalignedPtr, ALIGN_DWORD);
#if defined(_X86_)
#define ALIGN_BYTE 1
#define ALIGN_CHAR 1
#define ALIGN_DESC_CHAR sizeof(DESC_CHAR)
#define ALIGN_DWORD 4
#define ALIGN_LONG 4
#define ALIGN_LPBYTE 4
#define ALIGN_LPDWORD 4
#define ALIGN_LPSTR 4
#define ALIGN_LPTSTR 4
#define ALIGN_LPVOID 4
#define ALIGN_LPWORD 4
#define ALIGN_TCHAR sizeof(TCHAR)
#define ALIGN_WCHAR sizeof(WCHAR)
#define ALIGN_WORD 2
#define ALIGN_QUAD 8
#define ALIGN_WORST 8
#elif defined(_MIPS_) || defined(_ALPHA_) || defined(_PPC_)
#define ALIGN_BYTE 1
#define ALIGN_CHAR 1
#define ALIGN_DESC_CHAR sizeof(DESC_CHAR)
#define ALIGN_DWORD 4
#define ALIGN_LONG 4
#define ALIGN_LPBYTE 4
#define ALIGN_LPDWORD 4
#define ALIGN_LPSTR 4
#define ALIGN_LPTSTR 4
#define ALIGN_LPVOID 4
#define ALIGN_LPWORD 4
#define ALIGN_TCHAR sizeof(TCHAR)
#define ALIGN_WCHAR sizeof(WCHAR)
#define ALIGN_WORD 2
#define ALIGN_QUAD 8
//
// Worst-case alignment on MIPS is 8 bytes (for double). Specify this here,
// in case our allocator is used for structures containing this. (That is,
// even though NT/LAN doesn't need this for our data structures, let's be
// permissive.) The alignment requirements apply to Alpha.
//
#define ALIGN_WORST 8
#else // none of the above
#error "Unknown alignment requirements for align.h"
#endif // none of the above
#endif // _ALIGN_
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