1 /* 2 * Copyright (C) 2000, 2002-2003 Hewlett-Packard Co 3 * David Mosberger-Tang <davidm@hpl.hp.com> 4 * 5 * Kernel unwind support. 6 */ 7 8 #define UNW_VER(x) ((x) >> 48) 9 #define UNW_FLAG_MASK 0x0000ffff00000000 10 #define UNW_FLAG_OSMASK 0x0000f00000000000 11 #define UNW_FLAG_EHANDLER(x) ((x) & 0x0000000100000000L) 12 #define UNW_FLAG_UHANDLER(x) ((x) & 0x0000000200000000L) 13 #define UNW_LENGTH(x) ((x) & 0x00000000ffffffffL) 14 15 enum unw_register_index { 16 /* primary unat: */ 17 UNW_REG_PRI_UNAT_GR, 18 UNW_REG_PRI_UNAT_MEM, 19 20 /* register stack */ 21 UNW_REG_BSP, /* register stack pointer */ 22 UNW_REG_BSPSTORE, 23 UNW_REG_PFS, /* previous function state */ 24 UNW_REG_RNAT, 25 /* memory stack */ 26 UNW_REG_PSP, /* previous memory stack pointer */ 27 /* return pointer: */ 28 UNW_REG_RP, 29 30 /* preserved registers: */ 31 UNW_REG_R4, UNW_REG_R5, UNW_REG_R6, UNW_REG_R7, 32 UNW_REG_UNAT, UNW_REG_PR, UNW_REG_LC, UNW_REG_FPSR, 33 UNW_REG_B1, UNW_REG_B2, UNW_REG_B3, UNW_REG_B4, UNW_REG_B5, 34 UNW_REG_F2, UNW_REG_F3, UNW_REG_F4, UNW_REG_F5, 35 UNW_REG_F16, UNW_REG_F17, UNW_REG_F18, UNW_REG_F19, 36 UNW_REG_F20, UNW_REG_F21, UNW_REG_F22, UNW_REG_F23, 37 UNW_REG_F24, UNW_REG_F25, UNW_REG_F26, UNW_REG_F27, 38 UNW_REG_F28, UNW_REG_F29, UNW_REG_F30, UNW_REG_F31, 39 UNW_NUM_REGS 40 }; 41 42 struct unw_info_block { 43 u64 header; 44 u64 desc[0]; /* unwind descriptors */ 45 /* personality routine and language-specific data follow behind descriptors */ 46 }; 47 48 struct unw_table { 49 struct unw_table *next; /* must be first member! */ 50 const char *name; 51 unsigned long gp; /* global pointer for this load-module */ 52 unsigned long segment_base; /* base for offsets in the unwind table entries */ 53 unsigned long start; 54 unsigned long end; 55 const struct unw_table_entry *array; 56 unsigned long length; 57 }; 58 59 enum unw_where { 60 UNW_WHERE_NONE, /* register isn't saved at all */ 61 UNW_WHERE_GR, /* register is saved in a general register */ 62 UNW_WHERE_FR, /* register is saved in a floating-point register */ 63 UNW_WHERE_BR, /* register is saved in a branch register */ 64 UNW_WHERE_SPREL, /* register is saved on memstack (sp-relative) */ 65 UNW_WHERE_PSPREL, /* register is saved on memstack (psp-relative) */ 66 /* 67 * At the end of each prologue these locations get resolved to 68 * UNW_WHERE_PSPREL and UNW_WHERE_GR, respectively: 69 */ 70 UNW_WHERE_SPILL_HOME, /* register is saved in its spill home */ 71 UNW_WHERE_GR_SAVE /* register is saved in next general register */ 72 }; 73 74 #define UNW_WHEN_NEVER 0x7fffffff 75 76 struct unw_reg_info { 77 unsigned long val; /* save location: register number or offset */ 78 enum unw_where where; /* where the register gets saved */ 79 int when; /* when the register gets saved */ 80 }; 81 82 struct unw_reg_state { 83 struct unw_reg_state *next; /* next (outer) element on state stack */ 84 struct unw_reg_info reg[UNW_NUM_REGS]; /* register save locations */ 85 }; 86 87 struct unw_labeled_state { 88 struct unw_labeled_state *next; /* next labeled state (or NULL) */ 89 unsigned long label; /* label for this state */ 90 struct unw_reg_state saved_state; 91 }; 92 93 struct unw_state_record { 94 unsigned int first_region : 1; /* is this the first region? */ 95 unsigned int done : 1; /* are we done scanning descriptors? */ 96 unsigned int any_spills : 1; /* got any register spills? */ 97 unsigned int in_body : 1; /* are we inside a body (as opposed to a prologue)? */ 98 unsigned long flags; /* see UNW_FLAG_* in unwind.h */ 99 100 u8 *imask; /* imask of spill_mask record or NULL */ 101 unsigned long pr_val; /* predicate values */ 102 unsigned long pr_mask; /* predicate mask */ 103 long spill_offset; /* psp-relative offset for spill base */ 104 int region_start; 105 int region_len; 106 int epilogue_start; 107 int epilogue_count; 108 int when_target; 109 110 u8 gr_save_loc; /* next general register to use for saving a register */ 111 u8 return_link_reg; /* branch register in which the return link is passed */ 112 113 struct unw_labeled_state *labeled_states; /* list of all labeled states */ 114 struct unw_reg_state curr; /* current state */ 115 }; 116 117 enum unw_nat_type { 118 UNW_NAT_NONE, /* NaT not represented */ 119 UNW_NAT_VAL, /* NaT represented by NaT value (fp reg) */ 120 UNW_NAT_MEMSTK, /* NaT value is in unat word at offset OFF */ 121 UNW_NAT_REGSTK /* NaT is in rnat */ 122 }; 123 124 enum unw_insn_opcode { 125 UNW_INSN_ADD, /* s[dst] += val */ 126 UNW_INSN_ADD_PSP, /* s[dst] = (s.psp + val) */ 127 UNW_INSN_ADD_SP, /* s[dst] = (s.sp + val) */ 128 UNW_INSN_MOVE, /* s[dst] = s[val] */ 129 UNW_INSN_MOVE2, /* s[dst] = s[val]; s[dst+1] = s[val+1] */ 130 UNW_INSN_MOVE_STACKED, /* s[dst] = ia64_rse_skip(*s.bsp, val) */ 131 UNW_INSN_SETNAT_MEMSTK, /* s[dst+1].nat.type = MEMSTK; 132 s[dst+1].nat.off = *s.pri_unat - s[dst] */ 133 UNW_INSN_SETNAT_TYPE, /* s[dst+1].nat.type = val */ 134 UNW_INSN_LOAD, /* s[dst] = *s[val] */ 135 UNW_INSN_MOVE_SCRATCH, /* s[dst] = scratch reg "val" */ 136 }; 137 138 struct unw_insn { 139 unsigned int opc : 4; 140 unsigned int dst : 9; 141 signed int val : 19; 142 }; 143 144 /* 145 * Preserved general static registers (r4-r7) give rise to two script 146 * instructions; everything else yields at most one instruction; at 147 * the end of the script, the psp gets popped, accounting for one more 148 * instruction. 149 */ 150 #define UNW_MAX_SCRIPT_LEN (UNW_NUM_REGS + 5) 151 152 struct unw_script { 153 unsigned long ip; /* ip this script is for */ 154 unsigned long pr_mask; /* mask of predicates script depends on */ 155 unsigned long pr_val; /* predicate values this script is for */ 156 rwlock_t lock; 157 unsigned int flags; /* see UNW_FLAG_* in unwind.h */ 158 unsigned short lru_chain; /* used for least-recently-used chain */ 159 unsigned short coll_chain; /* used for hash collisions */ 160 unsigned short hint; /* hint for next script to try (or -1) */ 161 unsigned short count; /* number of instructions in script */ 162 struct unw_insn insn[UNW_MAX_SCRIPT_LEN]; 163 }; 164