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2008-10-13 16:13:16
title "Interlocked Support"
;++
;
; Copyright (c) 1989 Microsoft Corporation
;
; Module Name:
;
; intrlock.asm
;
; Abstract:
;
; This module implements functions to support interlocked operations.
; Interlocked operations can only operate on nonpaged data.
;
; Author:
;
; Shie-Lin Tzong (shielint) 12-Feb-1990
;
; Environment:
;
; Any mode.
;
; Revision History:
;
; bryanwi 1-aug-90 Clean up and fix stuff.
; bryanwi 3-aug-90 Add ExInterlockedIncrementLlong,...
;
;--
.386p
.xlist
include ks386.inc
include callconv.inc ; calling convention macros
include mac386.inc
.list
_TEXT$00 SEGMENT DWORD PUBLIC 'CODE'
ASSUME DS:FLAT, ES:FLAT, SS:NOTHING, FS:NOTHING, GS:NOTHING
;++
;
; General Notes on Interlocked Procedures:
;
; These procedures assume that neither their code, nor any of
; the data they touch, will cause a page fault.
;
; They use spinlocks to achieve MP atomicity, iff it's an MP machine.
; (The spinlock macros generate zilch if NT_UP = 1, and
; we if out some aux code here as well.)
;
; They turn off interrupts so that they can be used for synchronization
; between ISRs and driver code. Flags are preserved so they can
; be called in special code (Like IPC interrupt handlers) that
; may have interrupts off.
;
;--
;; align 512
page ,132
subttl "ExInterlockedAddLargeInteger"
;++
;
; LARGE_INTEGER
; ExInterlockedAddLargeInteger (
; IN PLARGE_INTEGER Addend,
; IN LARGE_INTEGER Increment,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function performs an interlocked add of an increment value to an
; addend variable of type unsigned large integer. The initial value of
; the addend variable is returned as the function value.
;
; Arguments:
;
; (TOS+4) = Addend - a pointer to the addend value
; (TOS+8) = Increment - the increment value
; (TOS+16) = Lock - a pointer to a pointer to a spin lock
;
; Return Value:
;
; The initial value of the addend variable is stored in eax:edx
;
;--
EiulAddend equ [ebp + 8]
EiulIncrement equ [ebp + 12]
EiulLock equ [ebp + 20]
EiulRetval equ [ebp - 8]
cPublicProc _ExInterlockedAddLargeInteger, 4
push ebp
mov ebp,esp
sub esp, 8
ifndef NT_UP
mov eax,EiulLock ; (eax) -> KSPIN_LOCK
endif
eiul10: pushfd
cli ; disable interrupts
ACQUIRE_SPINLOCK eax,
mov eax,EiulAddend ; (eax)-> addend variable
mov ecx,[eax] ; (ecx)= low part of addend value
mov edx,[eax]+4 ; (edx)= high part of addend value
mov EiulRetVal,ecx ; set low part of return value
mov EiulRetVal+4,edx ; set high part of return value
add ecx,EiulIncrement ; add low parts of large integer
adc edx,EiulIncrement+4 ; add high parts of large integer and carry
mov eax,EiulAddend ; RELOAD (eax)-> addend variable
mov [eax],ecx ; store low part of result
mov [eax]+4,edx ; store high part of result
ifndef NT_UP
mov eax,EiulLock
RELEASE_SPINLOCK eax ; NOTHING if NT_UP = 1
endif
popfd ; restore flags including interrupts
mov eax, EiulRetval ; calling convention
mov edx, EiulRetval+4 ; calling convention
mov esp, ebp
pop ebp
stdRET _ExInterlockedAddLargeInteger
ifndef NT_UP
eiul20: popfd
SPIN_ON_SPINLOCK eax, eiul10
endif
stdENDP _ExInterlockedAddLargeInteger
page ,132
subttl "ExInterlocked Exchange Add Large Integer"
;++
;
; LARGE_INTEGER
; ExInterlockedExchangeAddLargeInteger (
; IN PLARGE_INTEGER Addend,
; IN LARGE_INTEGER Increment,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function performs an interlocked add of an increment value to an
; addend variable of type unsigned large integer. The initial value of
; the addend variable is returned as the function value.
;
; N.B. The cmpxchg8b instruction is only supported on some processors.
; If the host processor does not support this instruction, then
; then following code is patched to contain a jump to the normal
; add large integer code which has a compatible calling sequence
; and data structure.
;
; Arguments:
;
; (TOS + 4) = Addend - Supplies a pointer to the addend variable.
;
; (TOS + 8) = Increment - Supplies the increment value.
;
; (TOS + 16) = Lock - Supplies a pointer a spin lock.
;
; N.B. This routine does not use the spin lock.
;
; Return Value:
;
; The initial value of the addend variable is stored in eax:edx.
;
;--
XaAddend equ [esp + 12]
XaIncrement equ [esp + 16]
XaLock equ [esp + 24]
cPublicProc _ExInterlockedExchangeAddLargeInteger, 4
cPublicFpo 0,2
;
; Save nonvolatile registers and get the addend value.
;
push ebx ; save nonvolatile registers
push ebp ;
mov ebp, XaAddend ; get the addend variable address
mov eax,[ebp] + 0 ; get low part of addend value
mov edx,[ebp] + 4 ; get high part of addend value
;
; Add the increment value to the addend value.
;
Xa10: mov ebx, eax ; copy low part of addend value
mov ecx, edx ; copy high part of addend value
add ebx, XaIncrement ; add low part of increment value
adc ecx, XaIncrement + 4 ; add high part of increment value
;
; Exchange the updated addend value with the previous addend value.
;
.586
ifndef NT_UP
lock cmpxchg8b qword ptr [ebp] ; compare and exchange
else
cmpxchg8b qword ptr [ebp] ; compare and exchange
endif
.386
jnz short Xa10 ; if z clear, exchange failed
;
; Restore nonvolatile registers and return result.
;
cPublicFpo 0,0
pop ebp ;
pop ebx ;
stdRET _ExInterlockedExchangeAddLargeInteger
stdENDP _ExInterlockedExchangeAddLargeInteger
page , 132
subttl "Interlocked Add Unsigned Long"
;++
;
; ULONG
; ExInterlockedAddUlong (
; IN PULONG Addend,
; IN ULONG Increment,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function performs an interlocked add of an increment value to an
; addend variable of type unsinged long. The initial value of the addend
; variable is returned as the function value.
;
; It is NOT possible to mix ExInterlockedDecrementLong and
; ExInterlockedIncrementong with ExInterlockedAddUlong.
;
;
; Arguments:
;
; Addend - Supplies a pointer to a variable whose value is to be
; adjusted by the increment value.
;
; Increment - Supplies the increment value to be added to the
; addend variable.
;
; Lock - Supplies a pointer to a spin lock to be used to synchronize
; access to the addend variable.
;
; Return Value:
;
; The initial value of the addend variable.
;
;--
EialAddend equ [esp + 8]
EialIncrement equ [esp + 12]
EialLock equ [esp + 16]
; end of arguments
cPublicProc _ExInterlockedAddUlong , 3
cPublicFpo 3, 1
ifdef NT_UP
;
; UP version of ExInterlockedAddUlong
;
pushfd
cli ; disable interrupts
mov ecx, EialAddend ; (ecx)->initial addend value
mov edx, [ecx] ; (edx)= initial addend value
mov eax, edx ; (eax)= initial addend value
add edx, EialIncrement ; (edx)=adjusted value
mov [ecx], edx ; [ecx]=adjusted value
popfd ; restore flags including ints
stdRET _ExInterlockedAddUlong ; cRetURN
else
;
; MP version of ExInterlockedAddUlong
;
pushfd
mov edx,EialLock ; (edx)-> KSPIN_LOCK
Eial10: cli ; disable interrupts
ACQUIRE_SPINLOCK edx,
mov ecx, EialAddend ; (ecx)->initial addend value
mov eax, [ecx] ; (eax)=initial addend value
add eax, EialIncrement ; (eax)=adjusted value
mov [ecx], eax ; [ecx]=adjusted value
sub eax, EialIncrement ; (eax)=initial addend value
RELEASE_SPINLOCK edx
popfd
stdRET _ExInterlockedAddUlong ; cRetURN
Eial20: popfd
pushfd
SPIN_ON_SPINLOCK edx,
endif
stdENDP _ExInterlockedAddUlong
page , 132
subttl "Interlocked Insert Head List"
;++
;
; PLIST_ENTRY
; ExInterlockedInsertHeadList (
; IN PLIST_ENTRY ListHead,
; IN PLIST_ENTRY ListEntry,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function inserts an entry at the head of a doubly linked list
; so that access to the list is synchronized in a multiprocessor system.
;
; N.B. The pages of data which this routine operates on MUST be
; present. No page fault is allowed in this routine.
;
; Arguments:
;
; ListHead - Supplies a pointer to the head of the doubly linked
; list into which an entry is to be inserted.
;
; ListEntry - Supplies a pointer to the entry to be inserted at the
; head of the list.
;
; Lock - Supplies a pointer to a spin lock to be used to synchronize
; access to the list.
;
; Return Value:
;
; Pointer to entry that was at the head of the list or NULL if the list
; was empty.
;
;--
EiihListHead equ [esp + 8]
EiihListEntry equ [esp + 12]
EiihLock equ [esp + 16]
; end arguments
cPublicProc _ExInterlockedInsertHeadList , 3
cPublicFpo 3, 1
ifndef NT_UP
mov edx, EiihLock - 4 ; (edx)->KSPIN_LOCK
endif
Eiih10: pushfd
cli
ACQUIRE_SPINLOCK edx,
mov eax, EiihListHead ; (eax)->head of linked list
mov ecx, EiihListEntry ; (ecx)->entry to be inserted
mov edx, LsFlink[eax] ; (edx)->next entry in the list
mov [ecx]+LsFlink, edx ; store next link in entry
mov [ecx]+LsBlink, eax ; store previous link in entry
mov [eax]+LsFlink, ecx ; store next link in head
mov [edx]+LsBlink, ecx ; store previous link in next
ifndef NT_UP
mov ecx, EiihLock ; (ecx)->KSPIN_LOCK
RELEASE_SPINLOCK ecx
endif
cPublicFpo 3, 0
popfd ; restore flags including interrupts
xor eax,edx ; return null if list was empty
jz short Eiih15
mov eax,edx ; otherwise return prev. entry at head
Eiih15:
stdRET _ExInterlockedInsertHeadList
ifndef NT_UP
align 4
Eiih20: popfd
SPIN_ON_SPINLOCK edx,
endif
stdENDP _ExInterlockedInsertHeadList
page , 132
subttl "Interlocked Insert Tail List"
;++
;
; PLIST_ENTRY
; ExInterlockedInsertTailList (
; IN PLIST_ENTRY ListHead,
; IN PLIST_ENTRY ListEntry,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function inserts an entry at the tail of a doubly linked list
; so that access to the list is synchronized in a multiprocessor system.
;
; N.B. The pages of data which this routine operates on MUST be
; present. No page fault is allowed in this routine.
;
; Arguments:
;
; ListHead - Supplies a pointer to the head of the doubly linked
; list into which an entry is to be inserted.
;
; ListEntry - Supplies a pointer to the entry to be inserted at the
; tail of the list.
;
; Lock - Supplies a pointer to a spin lock to be used to synchronize
; access to the list.
;
; Return Value:
;
; Pointer to entry that was at the tail of the list or NULL if the list
; was empty.
;
;--
EiitListHead equ [esp + 8]
EiitListEntry equ [esp + 12]
EiitLock equ [esp + 16]
; end arguments
cPublicProc _ExInterlockedInsertTailList , 3
cPublicFpo 3, 1
ifndef NT_UP
mov edx,EiitLock - 4 ; (edx)->KSPIN_LOCK
endif
Eiit10: pushfd
cli ; disable interrupts
ACQUIRE_SPINLOCK edx,
mov eax, EiihListHead ; (eax)->head of linked list
mov ecx, EiihListEntry ; (ecx)->entry to be inserted
mov edx, LsBlink[eax] ; (edx)->previous entry in the list
mov [ecx]+LsFlink, eax ; store next link in entry
mov [ecx]+LsBlink, edx ; store previous link in entry
mov [eax]+LsBlink, ecx ; store previous link in head
mov [edx]+LsFlink, ecx ; store next link in next
ifndef NT_UP
mov ecx,EiitLock ; (ecx)->KSPIN_LOCK
RELEASE_SPINLOCK ecx
endif
cPublicFpo 3,0
popfd ; restore flags including interrupts
xor eax,edx ; return null if list was empty
jz short Eiit15
mov eax,edx ; otherwise return prev. entry at tail
Eiit15:
stdRET _ExInterlockedInsertTailList
ifndef NT_UP
align 4
Eiit20: popfd
SPIN_ON_SPINLOCK edx,
endif
stdENDP _ExInterlockedInsertTailList
page , 132
subttl "Interlocked Remove Head List"
;++
;
; PLIST_ENTRY
; ExInterlockedRemoveHeadList (
; IN PLIST_ENTRY ListHead,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function removes an entry from the head of a doubly linked list
; so that access to the list is synchronized in a multiprocessor system.
; If there are no entries in the list, then a value of NULL is returned.
; Otherwise, the address of the entry that is removed is returned as the
; function value.
;
; N.B. The pages of data which this routine operates on MUST be
; present. No page fault is allowed in this routine.
;
; Arguments:
;
; ListHead - Supplies a pointer to the head of the doubly linked
; list from which an entry is to be removed.
;
; Lock - Supplies a pointer to a spin lock to be used to synchronize
; access to the list.
;
; Return Value:
;
; The address of the entry removed from the list, or NULL if the list is
; empty.
;
;--
EirhListHead equ [esp + 8]
EirhLock equ [esp + 12]
; end of arguments
cPublicProc _ExInterlockedRemoveHeadList , 2
cPublicFpo 2, 1
ifndef NT_UP
mov edx, EirhLock - 4 ; (edx)-> KSPIN_LOCK
endif
Eirh10: pushfd
cli
ACQUIRE_SPINLOCK edx,
mov edx, EirhListHead ; (edx)-> head of list
mov eax, [edx]+LsFlink ; (eax)-> next entry
cmp eax, edx ; Is list empty?
je short Eirh20 ; if e, list is empty, go Eirh20
mov ecx, [eax]+LsFlink ; (ecx)-> next entry(after deletion)
mov [edx]+LsFlink, ecx ; store address of next in head
mov [ecx]+LsBlink, edx ; store address of previous in next
if DBG
mov [eax]+LsFlink, 0baddd0ffh
mov [eax]+LsBlink, 0baddd0ffh
endif
ifndef NT_UP
mov edx, EirhLock ; (edx)-> KSPIN_LOCK
RELEASE_SPINLOCK edx
endif
cPublicFpo 2, 0
popfd ; restore flags including interrupts
stdRET _ExInterlockedRemoveHeadList ; cReturn entry
align 4
Eirh20:
ifndef NT_UP
mov edx, EirhLock ; (edx)-> KSPIN_LOCK
RELEASE_SPINLOCK edx
endif
popfd
xor eax,eax ; (eax) = null for empty list
stdRET _ExInterlockedRemoveHeadList ; cReturn NULL
ifndef NT_UP
align 4
Eirh30: popfd
SPIN_ON_SPINLOCK edx, Eirh10
endif
stdENDP _ExInterlockedRemoveHeadList
page , 132
subttl "Interlocked Pop Entry List"
;++
;
; PSINGLE_LIST_ENTRY
; ExInterlockedPopEntryList (
; IN PSINGLE_LIST_ENTRY ListHead,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function removes an entry from the front of a singly linked list
; so that access to the list is synchronized in a multiprocessor system.
; If there are no entries in the list, then a value of NULL is returned.
; Otherwise, the address of the entry that is removed is returned as the
; function value.
;
; Arguments:
;
; ListHead - Supplies a pointer to the head of the singly linked
; list from which an entry is to be removed.
;
; Lock - Supplies a pointer to a spin lock to be used to synchronize
; access to the list.
;
; Return Value:
;
; The address of the entry removed from the list, or NULL if the list is
; empty.
;
;--
; end of arguments
cPublicProc _ExInterlockedPopEntryList , 2
cPublicFpo 2,1
ifndef NT_UP
mov edx, [esp+8] ; (edx)-> KSPIN_LOCK
endif
Eipe10: pushfd
cli ; disable interrupts
ACQUIRE_SPINLOCK edx,
mov ecx, [esp+8] ; (ecx)-> head of list
mov eax, [ecx] ; (eax)-> next entry
or eax, eax ; Is it empty?
je short Eipe20 ; if e, empty list, go Eipe20
mov edx, [eax] ; (edx)->next entry (after deletion)
mov [ecx], edx ; store address of next in head
if DBG
mov [eax], 0baddd0ffh
endif
ifndef NT_UP
mov edx, [esp+12] ; (edx)-> KSPIN_LOCK
endif
Eipe15: RELEASE_SPINLOCK edx
cPublicFpo 2,0
popfd ; restore flags including interrupts
stdRET _ExInterlockedPopEntryList ; cReturn (eax)->removed entry
Eipe20: xor eax, eax ; return NULL for empty list
jmp short Eipe15 ; continue in common exit
ifndef NT_UP
Eipe30: popfd
SPIN_ON_SPINLOCK edx, Eipe10
endif
stdENDP _ExInterlockedPopEntryList
page , 132
subttl "Interlocked Push Entry List"
;++
;
; PSINGLE_LIST_ENTRY
; ExInterlockedPushEntryList (
; IN PSINGLE_LIST_ENTRY ListHead,
; IN PSINGLE_LIST_ENTRY ListEntry,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function inserts an entry at the head of a singly linked list
; so that access to the list is synchronized in a multiprocessor system.
;
; Arguments:
;
; ListHead - Supplies a pointer to the head of the singly linked
; list into which an entry is to be inserted.
;
; ListEntry - Supplies a pointer to the entry to be inserted at the
; head of the list.
;
; Lock - Supplies a pointer to a spin lock to be used to synchronize
; access to the list.
;
; Return Value:
;
; Previous contents of ListHead. NULL implies list went from empty
; to not empty.
;
;--
; end of arguments
cPublicProc _ExInterlockedPushEntryList , 3
cPublicFpo 3,1
ifndef NT_UP
mov edx, [esp+12] ; (edx)->KSPIN_LOCK
endif
Eipl10: pushfd
cli
ACQUIRE_SPINLOCK edx,
mov edx, [esp+8] ; (edx)-> Head of list
mov eax, [edx] ; (eax)-> next entry (return value also)
mov ecx, [esp+12] ; (ecx)-> Entry to be pushed
mov [ecx], eax ; store address of next in new entry
mov [edx], ecx ; set address of next in head
ifndef NT_UP
mov edx, [esp+16] ; (edx)->KSPIN_LOCK
RELEASE_SPINLOCK edx
endif
cPublicFpo 3,0
popfd ; restore flags including interrupts
stdRET _ExInterlockedPushEntryList
ifndef NT_UP
align 4
Eipl20: popfd
SPIN_ON_SPINLOCK edx,
endif
stdENDP _ExInterlockedPushEntryList
page , 132
subttl "Interlocked Increment Long"
;++
;
; INTERLOCKED_RESULT
; ExInterlockedIncrementLong (
; IN PLONG Addend,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function atomically increments Addend, returning an ennumerated
; type which indicates what interesting transitions in the value of
; Addend occurred due the operation.
;
; It is NOT possible to mix ExInterlockedDecrementLong and
; ExInterlockedIncrementong with ExInterlockedAddUlong.
;
;
; Arguments:
;
; Addend (esp+4) - Pointer to variable to increment.
;
; Lock (esp+8) - Spinlock used to implement atomicity.
; (not actually used on x86)
;
; Return Value:
;
; An ennumerated type:
;
; ResultNegative if Addend is < 0 after increment.
; ResultZero if Addend is = 0 after increment.
; ResultPositive if Addend is > 0 after increment.
;
;--
cPublicProc _ExInterlockedIncrementLong , 2
cPublicFpo 2, 0
mov eax, [esp+4] ; (eax) -> addend
ifdef NT_UP
add dword ptr [eax],1
else
lock add dword ptr [eax],1
endif
lahf ; (ah) = flags
and eax,EFLAG_SELECT ; clear all but sign and zero flags
stdRET _ExInterlockedIncrementLong
stdENDP _ExInterlockedIncrementLong
page , 132
subttl "Interlocked Decrement Long"
;++
;
; INTERLOCKED_RESULT
; ExInterlockedDecrementLong (
; IN PLONG Addend,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function atomically decrements Addend, returning an ennumerated
; type which indicates what interesting transitions in the value of
; Addend occurred due the operation.
;
; It is NOT possible to mix ExInterlockedDecrementLong and
; ExInterlockedIncrementong with ExInterlockedAddUlong.
;
; Arguments:
;
; Addend (esp+4) - Pointer to variable to decrement.
;
; Lock (esp+8) - Spinlock used to implement atomicity.
; (not actually used on x86)
;
; Return Value:
;
; An ennumerated type:
;
; ResultNegative if Addend is < 0 after decrement.
; ResultZero if Addend is = 0 after decrement.
; ResultPositive if Addend is > 0 after decrement.
;
;--
cPublicProc _ExInterlockedDecrementLong , 2
cPublicFpo 2, 0
mov eax, [esp+4] ; (eax) -> addend
ifdef NT_UP
sub dword ptr [eax], 1
else
lock sub dword ptr [eax], 1
endif
lahf ; (ah) = flags
and eax, EFLAG_SELECT ; clear all but sign and zero flags
stdRET _ExInterlockedDecrementLong
stdENDP _ExInterlockedDecrementLong
page , 132
subttl "Interlocked Exchange Ulong"
;++
;
; ULONG
; ExInterlockedExchangeUlong (
; IN PULONG Target,
; IN ULONG Value,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function atomically exchanges the Target and Value, returning
; the prior contents of Target
;
; This function does not necessarily synchronize with the Lock.
;
; Arguments:
;
; Target - Address of ULONG to exchange
; Value - New value of ULONG
; Lock - SpinLock used to implement atomicity.
;
; Return Value:
;
; The prior value of Source
;--
cPublicProc _ExInterlockedExchangeUlong, 3
cPublicFpo 3,0
ifndef NT_UP
mov edx, [esp+4] ; (edx) = Target
mov eax, [esp+8] ; (eax) = Value
xchg [edx], eax ; make the exchange
else
mov edx, [esp+4] ; (edx) = Target
mov ecx, [esp+8] ; (eax) = Value
pushfd
cli
mov eax, [edx] ; get current value
mov [edx], ecx ; store new value
popfd
endif
stdRET _ExInterlockedExchangeUlong
stdENDP _ExInterlockedExchangeUlong
page , 132
subttl "Interlocked i386 Increment Long"
;++
;
; INTERLOCKED_RESULT
; Exi386InterlockedIncrementLong (
; IN PLONG Addend
; )
;
; Routine Description:
;
; This function atomically increments Addend, returning an ennumerated
; type which indicates what interesting transitions in the value of
; Addend occurred due the operation.
;
; See ExInterlockedIncrementLong. This function is the i386
; architectural specific version of ExInterlockedIncrementLong.
; No source directly calls this function, instead
; ExInterlockedIncrementLong is called and when built on x86 these
; calls are macroed to the i386 optimized version.
;
; Arguments:
;
; Addend (esp+4) - Pointer to variable to increment.
;
; Lock (esp+8) - Spinlock used to implement atomicity.
; (not actually used on x86)
;
; Return Value:
;
; An ennumerated type:
;
; ResultNegative if Addend is < 0 after increment.
; ResultZero if Addend is = 0 after increment.
; ResultPositive if Addend is > 0 after increment.
;
;--
cPublicProc _Exi386InterlockedIncrementLong , 1
cPublicFpo 1, 0
mov eax, [esp+4] ; (eax) -> addend
ifdef NT_UP
add dword ptr [eax],1
else
lock add dword ptr [eax],1
endif
lahf ; (ah) = flags
and eax,EFLAG_SELECT ; clear all but sign and zero flags
stdRET _Exi386InterlockedIncrementLong
stdENDP _Exi386InterlockedIncrementLong
page , 132
subttl "Interlocked i386 Decrement Long"
;++
;
; INTERLOCKED_RESULT
; ExInterlockedDecrementLong (
; IN PLONG Addend,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function atomically decrements Addend, returning an ennumerated
; type which indicates what interesting transitions in the value of
; Addend occurred due the operation.
;
; See Exi386InterlockedDecrementLong. This function is the i386
; architectural specific version of ExInterlockedDecrementLong.
; No source directly calls this function, instead
; ExInterlockedDecrementLong is called and when built on x86 these
; calls are macroed to the i386 optimized version.
;
; Arguments:
;
; Addend (esp+4) - Pointer to variable to decrement.
;
; Lock (esp+8) - Spinlock used to implement atomicity.
; (not actually used on x86)
;
; Return Value:
;
; An ennumerated type:
;
; ResultNegative if Addend is < 0 after decrement.
; ResultZero if Addend is = 0 after decrement.
; ResultPositive if Addend is > 0 after decrement.
;
;--
cPublicProc _Exi386InterlockedDecrementLong , 1
cPublicFpo 1, 0
mov eax, [esp+4] ; (eax) -> addend
ifdef NT_UP
sub dword ptr [eax], 1
else
lock sub dword ptr [eax], 1
endif
lahf ; (ah) = flags
and eax, EFLAG_SELECT ; clear all but sign and zero flags
stdRET _Exi386InterlockedDecrementLong
stdENDP _Exi386InterlockedDecrementLong
page , 132
subttl "Interlocked i386 Exchange Ulong"
;++
;
; ULONG
; Exi386InterlockedExchangeUlong (
; IN PULONG Target,
; IN ULONG Value,
; IN PKSPIN_LOCK Lock
; )
;
; Routine Description:
;
; This function atomically exchanges the Target and Value, returning
; the prior contents of Target
;
; See Exi386InterlockedExchangeUlong. This function is the i386
; architectural specific version of ExInterlockedDecrementLong.
; No source directly calls this function, instead
; ExInterlockedDecrementLong is called and when built on x86 these
; calls are macroed to the i386 optimized version.
;
; Arguments:
;
; Source - Address of ULONG to exchange
; Value - New value of ULONG
; Lock - SpinLock used to implement atomicity.
;
; Return Value:
;
; The prior value of Source
;--
cPublicProc _Exi386InterlockedExchangeUlong, 2
cPublicFpo 2,0
ifndef NT_UP
mov edx, [esp+4] ; (edx) = Target
mov eax, [esp+8] ; (eax) = Value
xchg [edx], eax ; make the exchange
else
mov edx, [esp+4] ; (edx) = Target
mov ecx, [esp+8] ; (eax) = Value
pushfd
cli
mov eax, [edx] ; get current value
mov [edx], ecx ; store new value
popfd
endif
stdRET _Exi386InterlockedExchangeUlong
stdENDP _Exi386InterlockedExchangeUlong
_TEXT$00 ends
end
