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libsst/libsst-atomic/SST_Atomic_x86-64-win64.asm
2026-04-03 00:22:39 -05:00

238 lines
7.0 KiB
NASM

; SST_Atomic_x86-64-win64.asm
; Author: Patrick Baggett <ptbaggett@762studios.com>
; Created: 12/27/2011
;
; Purpose:
;
; 64-bit assembly for atomic operations using the Microsoft x64 ABI
; Assembles with YASM 1.1/NASM 2.0+
;
; License:
;
; This program is free software. It comes without any warranty, to
; the extent permitted by applicable law. You can redistribute it
; and/or modify it under the terms of the Do What The Fuck You Want
; To Public License, Version 2, as published by Sam Hocevar. See
; http://sam.zoy.org/wtfpl/COPYING for more details.
; Win64 and UNIX calling conventions differ for x64-64. I know, it's absurd.
; Because of this, there are separate implementation for Win64 and x64-64 UNIX (Linux, *BSD, Solaris, MacOS X, etc.)
; Here is the break down:
;
; REGISTER | Win64 | UNIX
;-----------+-----------+----------
;rax | Retval | Retval
;rdi | Not used | 1st arg
;rsi | Not used | 2nd arg
;rcx | 1st arg | 3rd arg
;rdx | 2nd arg | 4th arg
;r8 | 3rd arg | 5th arg
;r9 | 4th arg | 6th arg
[bits 64]
[segment .text]
; Win32 symbol names
[global SST_Atomic_Add]
[global SST_Atomic_AddPtr]
[global SST_Atomic_And]
[global SST_Atomic_Or]
[global SST_Atomic_Xor]
[global SST_Atomic_Not]
[global SST_Atomic_AddReturn]
[global SST_Atomic_AddPtrReturn]
[global SST_Atomic_AndReturn]
[global SST_Atomic_OrReturn]
[global SST_Atomic_XorReturn]
[global SST_Atomic_NotReturn]
[global SST_Atomic_ExchangeAdd]
[global SST_Atomic_ExchangeAddPtr]
[global SST_Atomic_Exchange]
[global SST_Atomic_ExchangePtr]
[global SST_Atomic_CAS]
[global SST_Atomic_CASPtr]
[global SST_Atomic_LoadAcquire]
[global SST_Atomic_LoadAcquirePtr]
[global SST_Atomic_StoreRelease]
[global SST_Atomic_StoreReleasePtr]
;=======================================================================
; Pointers and integers are different sized (64 bits vs 32 bits) so
; each SST_Atomic_XxxxPtr() function uses the full 64-bit registers.
;=======================================================================
;====================================================
; MICROSOFT WIN64 ABI
;====================================================
;void SST_Atomic_Add(volatile int* x, int value)
SST_Atomic_Add:
lock add [rcx], edx
ret
;void SST_Atomic_AddPtr(volatile void** x, int value)
SST_Atomic_AddPtr:
lock add [rcx], rdx
ret
; void SST_Atomic_And(volatile int* x, int value)
SST_Atomic_And:
lock and [rcx], edx
ret
; void SST_Atomic_Or(volatile int* x, int value)
SST_Atomic_Or:
lock or [rcx], edx
ret
; void SST_Atomic_Xor(volatile int* x, int value)
SST_Atomic_Xor:
lock xor [rcx], edx
ret
; void SST_Atomic_Not(volatile int* x)
SST_Atomic_Not:
lock not DWORD [rcx]
ret
; int SST_Atomic_AddReturn(volatile int* x, int value)
SST_Atomic_AddReturn:
mov eax, edx
lock xadd [rcx], eax ; eax contains orig value before xadd
add eax, edx ; now add 'value' (in edx) to get the sum that was stored in *x
ret
; int SST_Atomic_AddReturn(volatile void** x, int value)
SST_Atomic_AddPtrReturn:
mov rax, rdx
lock xadd [rcx], rax ; rax contains orig value before xadd
add rax, rdx ; now add 'value' (in rdx) to get the sum that was stored in *x
ret
; int SST_Atomic_AndReturn(volatile int* x, int value)
SST_Atomic_AndReturn:
mov eax, [rcx] ;eax = *x
mov r8d, eax ;r8d = *x
try_again_5:
and r8d, edx ;r8d <- *x & value
lock cmpxchg [rcx], r8d ;if(eax == *x) *x = r8d, else eax = *x
jz done_5 ;success -> *x was successfully updated. Its new value is in r8d.
mov r8d, eax ;failure -> *x was changed previous, new value is in eax. Copy that new value to r8d, let's try again
jmp try_again_5
done_5:
mov eax,r8d ;r8d has the value (*x & value), so mov to eax for return value
ret
SST_Atomic_OrReturn:
mov eax, [rcx] ;eax = *x
mov r8d, eax ;r8d = *x
try_again_6:
or r8d, edx ;r8d <- *x | value
lock cmpxchg [rcx], r8d ;if(eax == *x) *x = r8d, else eax = *x
jz done_6 ;success -> *x was successfully updated. Its new value is in r8d.
mov r8d, eax ;failure -> *x was changed previous, new value is in eax. Copy that new value to r8d, let's try again
jmp try_again_6
done_6:
mov eax,r8d ;r8d has the value (*x & value), so mov to eax for return value
ret
SST_Atomic_XorReturn:
mov eax, [rcx] ;eax = *x
mov r8d, eax ;r8d = *x
try_again_7:
xor r8d, edx ;r8d <- *x ^ value
lock cmpxchg [rcx], r8d ;if(eax == *x) *x = r8d, else eax = *x
jz done_7 ;success -> *x was successfully updated. Its new value is in r8d.
mov r8d, eax ;failure -> *x was changed previous, new value is in eax. Copy that new value to r8d, let's try again
jmp try_again_7
done_7:
mov eax,r8d ;r8d has the value (*x & value), so mov to eax for return value
ret
; int SST_Atomic_NotReturn(volatile int* x)
SST_Atomic_NotReturn:
mov eax, [rcx] ;eax = *x
mov r8d, eax ;r8d = *x
try_again_8:
not r8d ;r8d <- ~*x
lock cmpxchg [rcx], r8d ;if(eax == *x) *x = r8d, else eax = *x
jz done_8 ;success -> *x was successfully updated. Its new value is in r8d.
mov r8d, eax ;failure -> *x was changed previous, new value is in eax. Copy that new value to r8d, let's try again
jmp try_again_8
done_8:
mov eax,r8d ;r8d has the value (*x & value), so mov to eax for return value
ret
;int SST_Atomic_Exchange(volatile int* x, int value)
SST_Atomic_Exchange:
lock xchg [rcx], edx
mov eax, edx
ret
;void* SST_Atomic_ExchangePtr(volatile void** x, void* value)
SST_Atomic_ExchangePtr:
lock xchg [rcx], rdx
mov rax, rdx
ret
;int SST_Atomic_ExchangeAdd(volatile int* x, int value);
SST_Atomic_ExchangeAdd:
lock xadd [rcx], edx
mov eax, edx
ret
;void* SST_Atomic_ExchangeAddPtr(volatile void** x, int value);
SST_Atomic_ExchangeAddPtr:
lock xadd [rcx], rdx
mov rax, rdx
ret
;int SST_Atomic_CAS(int* dest, int compare, int newValue);
SST_Atomic_CAS:
;rcx <- dest
;edx <- compare
;r8d <- newValue
mov eax, edx
lock cmpxchg [rcx], r8d ;compare [rcx] with eax | swap with r8d if equal, else store [rcx] into eax
ret
;void* SST_Atomic_CASPtr(void** dest, void* compare, void* newValue);
SST_Atomic_CASPtr:
;rcx <- dest
;rdx <- compare
;r8 <- newValue
mov rax, rdx
lock cmpxchg [rcx], r8 ;compare [rcx] with rax | swap with r8 if equal, else store [rcx] into eax
ret
; int SST_Atomic_LoadAcquire(const volatile int* src);
; NOTE: x86 has strong memory ordering, thus no barrier is necessary, except for compiler barrier to reordering instructions
SST_Atomic_LoadAcquire:
mov eax, [rcx]
ret
; void* SST_Atomic_LoadAcquirePtr(const volatile void** src);
; NOTE: x86 has strong memory ordering, thus no barrier is necessary, except for compiler barrier to reordering instructions
SST_Atomic_LoadAcquirePtr:
mov rax, [rcx]
ret
; void SST_Atomic_StoreRelease(volatile int* dest, int value);
; NOTE: x86 has strong memory ordering, thus no barrier is necessary, except for compiler barrier to reordering instructions
SST_Atomic_StoreRelease:
mov [rcx], edx
ret
; void SST_Atomic_StoreReleasePtr(volatile void** dest, void* value);
; NOTE: x86 has strong memory ordering, thus no barrier is necessary, except for compiler barrier to reordering instructions
SST_Atomic_StoreReleasePtr:
mov [rcx], rdx
ret