1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef _ASM_S390_ASM_H
 3#define _ASM_S390_ASM_H
 4
 5#include <linux/stringify.h>
 6
 7/*
 8 * Helper macros to be used for flag output operand handling.
 9 * Inline assemblies must use four of the five supplied macros:
10 *
11 * Use CC_IPM(sym) at the end of the inline assembly; this extracts the
12 * condition code and program mask with the ipm instruction and writes it to
13 * the variable with symbolic name [sym] if the compiler has no support for
14 * flag output operands. If the compiler has support for flag output operands
15 * this generates no code.
16 *
17 * Use CC_OUT(sym, var) at the output operand list of an inline assembly. This
18 * defines an output operand with symbolic name [sym] for the variable
19 * [var]. [var] must be an int variable and [sym] must be identical with [sym]
20 * used with CC_IPM().
21 *
22 * Use either CC_CLOBBER or CC_CLOBBER_LIST() for the clobber list. Use
23 * CC_CLOBBER if the clobber list contains only "cc", otherwise use
24 * CC_CLOBBER_LIST() and add all clobbers as argument to the macro.
25 *
26 * Use CC_TRANSFORM() to convert the variable [var] which contains the
27 * extracted condition code. If the condition code is extracted with ipm, the
28 * [var] also contains the program mask. CC_TRANSFORM() moves the condition
29 * code to the two least significant bits and sets all other bits to zero.
30 */
31#if defined(__GCC_ASM_FLAG_OUTPUTS__) && !(IS_ENABLED(CONFIG_GCC_ASM_FLAG_OUTPUT_BROKEN))
32
33#define __HAVE_ASM_FLAG_OUTPUTS__
34
35#define CC_IPM(sym)
36#define CC_OUT(sym, var)	"=@cc" (var)
37#define CC_TRANSFORM(cc)	({ cc; })
38#define CC_CLOBBER
39#define CC_CLOBBER_LIST(...)	__VA_ARGS__
40
41#else
42
43#define CC_IPM(sym)		"	ipm	%[" __stringify(sym) "]\n"
44#define CC_OUT(sym, var)	[sym] "=d" (var)
45#define CC_TRANSFORM(cc)	({ (cc) >> 28; })
46#define CC_CLOBBER		"cc"
47#define CC_CLOBBER_LIST(...)	"cc", __VA_ARGS__
48
49#endif
50
51#endif /* _ASM_S390_ASM_H */