xref: /linux/arch/x86/include/asm/rmwcc.h (revision ca853314e78b0a65c20b6a889a23c31f918d4aa2)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_RMWcc
3 #define _ASM_X86_RMWcc
4 
5 /* This counts to 12. Any more, it will return 13th argument. */
6 #define __RMWcc_ARGS(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _n, X...) _n
7 #define RMWcc_ARGS(X...) __RMWcc_ARGS(, ##X, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
8 
9 #define __RMWcc_CONCAT(a, b) a ## b
10 #define RMWcc_CONCAT(a, b) __RMWcc_CONCAT(a, b)
11 
12 #define __CLOBBERS_MEM(clb...)	"memory", ## clb
13 
14 #if !defined(__GCC_ASM_FLAG_OUTPUTS__) && defined(CONFIG_CC_HAS_ASM_GOTO)
15 
16 /* Use asm goto */
17 
18 #define __GEN_RMWcc(fullop, _var, cc, clobbers, ...)			\
19 ({									\
20 	bool c = false;							\
21 	asm_volatile_goto (fullop "; j" #cc " %l[cc_label]"		\
22 			: : [var] "m" (_var), ## __VA_ARGS__		\
23 			: clobbers : cc_label);				\
24 	if (0) {							\
25 cc_label:	c = true;						\
26 	}								\
27 	c;								\
28 })
29 
30 #else /* defined(__GCC_ASM_FLAG_OUTPUTS__) || !defined(CONFIG_CC_HAS_ASM_GOTO) */
31 
32 /* Use flags output or a set instruction */
33 
34 #define __GEN_RMWcc(fullop, _var, cc, clobbers, ...)			\
35 ({									\
36 	bool c;								\
37 	asm volatile (fullop CC_SET(cc)					\
38 			: [var] "+m" (_var), CC_OUT(cc) (c)		\
39 			: __VA_ARGS__ : clobbers);			\
40 	c;								\
41 })
42 
43 #endif /* defined(__GCC_ASM_FLAG_OUTPUTS__) || !defined(CONFIG_CC_HAS_ASM_GOTO) */
44 
45 #define GEN_UNARY_RMWcc_4(op, var, cc, arg0)				\
46 	__GEN_RMWcc(op " " arg0, var, cc, __CLOBBERS_MEM())
47 
48 #define GEN_UNARY_RMWcc_3(op, var, cc)					\
49 	GEN_UNARY_RMWcc_4(op, var, cc, "%[var]")
50 
51 #define GEN_UNARY_RMWcc(X...) RMWcc_CONCAT(GEN_UNARY_RMWcc_, RMWcc_ARGS(X))(X)
52 
53 #define GEN_BINARY_RMWcc_6(op, var, cc, vcon, _val, arg0)		\
54 	__GEN_RMWcc(op " %[val], " arg0, var, cc,			\
55 		    __CLOBBERS_MEM(), [val] vcon (_val))
56 
57 #define GEN_BINARY_RMWcc_5(op, var, cc, vcon, val)			\
58 	GEN_BINARY_RMWcc_6(op, var, cc, vcon, val, "%[var]")
59 
60 #define GEN_BINARY_RMWcc(X...) RMWcc_CONCAT(GEN_BINARY_RMWcc_, RMWcc_ARGS(X))(X)
61 
62 #define GEN_UNARY_SUFFIXED_RMWcc(op, suffix, var, cc, clobbers...)	\
63 	__GEN_RMWcc(op " %[var]\n\t" suffix, var, cc,			\
64 		    __CLOBBERS_MEM(clobbers))
65 
66 #define GEN_BINARY_SUFFIXED_RMWcc(op, suffix, var, cc, vcon, _val, clobbers...)\
67 	__GEN_RMWcc(op " %[val], %[var]\n\t" suffix, var, cc,		\
68 		    __CLOBBERS_MEM(clobbers), [val] vcon (_val))
69 
70 #endif /* _ASM_X86_RMWcc */
71