kernel/vdso64/sigtramp.S

1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3  * Signal trampoline for 64 bits processes in a ppc64 kernel for
30    chosen in such a way that older libgcc unwind code returns a zero
31    for a sigcontext pointer.  */
32 	.long 0,0,0
33 	.quad 0,-21*8
35 /* Register r1 can be found at offset 8 of a pt_regs structure.
36    A pointer to the pt_regs is stored in memory at the old sp plus PTREGS.  */
38   .byte 0x0f;			/* DW_CFA_def_cfa_expression */		\
39   .uleb128 9f - 1f;		/*   length */				\
41   .byte 0x71; .sleb128 PTREGS;	/*     DW_OP_breg1 */			\
42   .byte 0x06;			/*     DW_OP_deref */			\
43   .byte 0x23; .uleb128 RSIZE;	/*     DW_OP_plus_uconst */		\
44   .byte 0x06;			/*     DW_OP_deref */			\
45 9:
47 /* Register REGNO can be found at offset OFS of a pt_regs structure.
48    A pointer to the pt_regs is stored in memory at the old sp plus PTREGS.  */
50   .byte 0x10;			/* DW_CFA_expression */			\
52   .uleb128 9f - 1f;		/*   length */				\
54   .byte 0x71; .sleb128 PTREGS;	/*     DW_OP_breg1 */			\
55   .byte 0x06;			/*     DW_OP_deref */			\
57     .byte 0x23; .uleb128 ofs;	/*     DW_OP_plus_uconst */		\
59 9:
62    of the VMX reg struct.  A pointer to the VMX reg struct is at VREGS in
63    the pt_regs struct.  This macro is for REGNO == 0, and contains
66   .byte 0x10;			/* DW_CFA_expression */			\
68   .uleb128 9f - 1f;		/*   length */				\
70   .byte 0x30 + regno;		/*     DW_OP_lit0 */			\
72   .byte 0x40;			/*     DW_OP_lit16 */			\
73   .byte 0x1e;			/*     DW_OP_mul */			\
75   .byte 0x71; .sleb128 PTREGS;	/*     DW_OP_breg1 */			\
76   .byte 0x06;			/*     DW_OP_deref */			\
77   .byte 0x12;			/*     DW_OP_dup */			\
78   .byte 0x23;			/*     DW_OP_plus_uconst */		\
80   .byte 0x06;			/*     DW_OP_deref */			\
81   .byte 0x0c; .long 1 << 25;	/*     DW_OP_const4u */			\
82   .byte 0x1a;			/*     DW_OP_and */			\
83   .byte 0x12;			/*     DW_OP_dup, ret 0 if bra taken */	\
84   .byte 0x30;			/*     DW_OP_lit0 */			\
85   .byte 0x29;			/*     DW_OP_eq */			\
86   .byte 0x28; .short 0x7fff;	/*     DW_OP_bra to end */		\
87   .byte 0x13;			/*     DW_OP_drop, pop the 0 */		\
88   .byte 0x23; .uleb128 VREGS;	/*     DW_OP_plus_uconst */		\
89   .byte 0x06;			/*     DW_OP_deref */			\
90   .byte 0x22;			/*     DW_OP_plus */			\
91   .byte 0x2f; .short 0x7fff;	/*     DW_OP_skip to end */		\
92 9:
97   .byte 0x10;			/* DW_CFA_expression */			\
99   .uleb128 9f - 1f;		/*   length */				\
101   .byte 0x30 + regno;		/*     DW_OP_lit n */			\
102   .byte 0x2f; .short 2b - 9f;	/*     DW_OP_skip */			\
103 9:
108   .byte 0x10;			/* DW_CFA_expression */			\
110   .uleb128 9f - 1f;		/*   length */				\
112   .byte 0x0a; .short ofs;	/*     DW_OP_const2u */			\
113   .byte 0x2f; .short 3b - 9f;	/*     DW_OP_skip */			\
114 9:
118   .byte 0x10;			/* DW_CFA_expression */			\
120   .uleb128 9f - 1f;		/*   length */				\
122   .byte 0x71; .sleb128 PTREGS;	/*     DW_OP_breg1 */			\
123   .byte 0x06;			/*     DW_OP_deref */			\
124   .byte 0x23; .uleb128 VREGS;	/*     DW_OP_plus_uconst */		\
125   .byte 0x06;			/*     DW_OP_deref */			\
126   .byte 0x23; .uleb128 ofs;	/*     DW_OP_plus_uconst */		\
127 9:
138 /* Offset of CR reg within a full word. */
140 #define CROFF 0
142 #define CROFF (RSIZE - CRSIZE)
151   rsave ( 0,  0*RSIZE);							\
159   rsave ( 9,  9*RSIZE);							\
195   rsave (32, 48*RSIZE +  0*8);						\
204   rsave (41, 48*RSIZE +  9*8);						\
231   vsave_msr0 ( 0);							\
240   vsave_msr1 ( 9);							\
269 	.section .eh_frame,"a",@progbits
271 	.long .Lcie_end - .Lcie_start
273 	.long 0			/* CIE ID */
275 	.string "zRS"		/* NUL-terminated augmentation string */
277 	.sleb128 -8		/* Data alignment factor */
280 	.byte 0x14		/* DW_EH_PE_pcrel | DW_EH_PE_udata8. */
281 	.byte 0x0c,1,0		/* DW_CFA_def_cfa: r1 ofs 0 */
285 	.long .Lfde0_end - .Lfde0_start
287 	.long .Lfde0_start - .Lcie	/* CIE pointer. */
288 	.quad .Lsigrt_start - .		/* PC start, length */
289 	.quad .Lsigrt_end - .Lsigrt_start
290 	.uleb128 0			/* Augmentation */
297 #	.byte 0x41		/* DW_CFA_advance_loc 1*4 */