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- /* DWARF2 exception handling and frame unwind runtime interface routines.
- Copyright (C) 1997-2022 Free Software Foundation, Inc.
- This file is part of GCC.
- GCC is free software; you can redistribute it and/or modify it
- under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 3, or (at your option)
- any later version.
- GCC is distributed in the hope that it will be useful, but WITHOUT
- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
- License for more details.
- Under Section 7 of GPL version 3, you are granted additional
- permissions described in the GCC Runtime Library Exception, version
- 3.1, as published by the Free Software Foundation.
- You should have received a copy of the GNU General Public License and
- a copy of the GCC Runtime Library Exception along with this program;
- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
- <http://www.gnu.org/licenses/>. */
- #include "tconfig.h"
- #include "tsystem.h"
- #include "coretypes.h"
- #include "tm.h"
- #include "dwarf2.h"
- #include "unwind.h"
- #ifdef __USING_SJLJ_EXCEPTIONS__
- # define NO_SIZE_OF_ENCODED_VALUE
- #endif
- #include "unwind-pe.h"
- #include "unwind-dw2-fde.h"
- #include "gthr.h"
- #include "unwind-dw2.h"
- #ifdef HAVE_SYS_SDT_H
- #include <sys/sdt.h>
- #endif
- #ifndef __USING_SJLJ_EXCEPTIONS__
- #ifndef __LIBGCC_STACK_GROWS_DOWNWARD__
- #define __LIBGCC_STACK_GROWS_DOWNWARD__ 0
- #else
- #undef __LIBGCC_STACK_GROWS_DOWNWARD__
- #define __LIBGCC_STACK_GROWS_DOWNWARD__ 1
- #endif
- /* Dwarf frame registers used for pre gcc 3.0 compiled glibc. */
- #ifndef PRE_GCC3_DWARF_FRAME_REGISTERS
- #define PRE_GCC3_DWARF_FRAME_REGISTERS __LIBGCC_DWARF_FRAME_REGISTERS__
- #endif
- #ifndef DWARF_REG_TO_UNWIND_COLUMN
- #define DWARF_REG_TO_UNWIND_COLUMN(REGNO) (REGNO)
- #endif
- #ifdef REG_VALUE_IN_UNWIND_CONTEXT
- typedef _Unwind_Word _Unwind_Context_Reg_Val;
- #ifndef ASSUME_EXTENDED_UNWIND_CONTEXT
- #define ASSUME_EXTENDED_UNWIND_CONTEXT 1
- #endif
- static inline _Unwind_Word
- _Unwind_Get_Unwind_Word (_Unwind_Context_Reg_Val val)
- {
- return val;
- }
- static inline _Unwind_Context_Reg_Val
- _Unwind_Get_Unwind_Context_Reg_Val (_Unwind_Word val)
- {
- return val;
- }
- #else
- typedef void *_Unwind_Context_Reg_Val;
- static inline _Unwind_Word
- _Unwind_Get_Unwind_Word (_Unwind_Context_Reg_Val val)
- {
- return (_Unwind_Word) (_Unwind_Internal_Ptr) val;
- }
- static inline _Unwind_Context_Reg_Val
- _Unwind_Get_Unwind_Context_Reg_Val (_Unwind_Word val)
- {
- return (_Unwind_Context_Reg_Val) (_Unwind_Internal_Ptr) val;
- }
- #endif
- #ifndef ASSUME_EXTENDED_UNWIND_CONTEXT
- #define ASSUME_EXTENDED_UNWIND_CONTEXT 0
- #endif
- /* This is the register and unwind state for a particular frame. This
- provides the information necessary to unwind up past a frame and return
- to its caller. */
- struct _Unwind_Context
- {
- _Unwind_Context_Reg_Val reg[__LIBGCC_DWARF_FRAME_REGISTERS__+1];
- void *cfa;
- void *ra;
- void *lsda;
- struct dwarf_eh_bases bases;
- /* Signal frame context. */
- #define SIGNAL_FRAME_BIT ((~(_Unwind_Word) 0 >> 1) + 1)
- /* Context which has version/args_size/by_value fields. */
- #define EXTENDED_CONTEXT_BIT ((~(_Unwind_Word) 0 >> 2) + 1)
- _Unwind_Word flags;
- /* 0 for now, can be increased when further fields are added to
- struct _Unwind_Context. */
- _Unwind_Word version;
- _Unwind_Word args_size;
- char by_value[__LIBGCC_DWARF_FRAME_REGISTERS__+1];
- };
- /* Byte size of every register managed by these routines. */
- static unsigned char dwarf_reg_size_table[__LIBGCC_DWARF_FRAME_REGISTERS__+1];
- /* Read unaligned data from the instruction buffer. */
- union unaligned
- {
- void *p;
- unsigned u2 __attribute__ ((mode (HI)));
- unsigned u4 __attribute__ ((mode (SI)));
- unsigned u8 __attribute__ ((mode (DI)));
- signed s2 __attribute__ ((mode (HI)));
- signed s4 __attribute__ ((mode (SI)));
- signed s8 __attribute__ ((mode (DI)));
- } __attribute__ ((packed));
- static void uw_update_context (struct _Unwind_Context *, _Unwind_FrameState *);
- static _Unwind_Reason_Code uw_frame_state_for (struct _Unwind_Context *,
- _Unwind_FrameState *);
- static inline void *
- read_pointer (const void *p) { const union unaligned *up = p; return up->p; }
- static inline int
- read_1u (const void *p) { return *(const unsigned char *) p; }
- static inline int
- read_1s (const void *p) { return *(const signed char *) p; }
- static inline int
- read_2u (const void *p) { const union unaligned *up = p; return up->u2; }
- static inline int
- read_2s (const void *p) { const union unaligned *up = p; return up->s2; }
- static inline unsigned int
- read_4u (const void *p) { const union unaligned *up = p; return up->u4; }
- static inline int
- read_4s (const void *p) { const union unaligned *up = p; return up->s4; }
- static inline unsigned long
- read_8u (const void *p) { const union unaligned *up = p; return up->u8; }
- static inline unsigned long
- read_8s (const void *p) { const union unaligned *up = p; return up->s8; }
- static inline _Unwind_Word
- _Unwind_IsSignalFrame (struct _Unwind_Context *context)
- {
- return (context->flags & SIGNAL_FRAME_BIT) ? 1 : 0;
- }
- static inline void
- _Unwind_SetSignalFrame (struct _Unwind_Context *context, int val)
- {
- if (val)
- context->flags |= SIGNAL_FRAME_BIT;
- else
- context->flags &= ~SIGNAL_FRAME_BIT;
- }
- static inline _Unwind_Word
- _Unwind_IsExtendedContext (struct _Unwind_Context *context)
- {
- return (ASSUME_EXTENDED_UNWIND_CONTEXT
- || (context->flags & EXTENDED_CONTEXT_BIT));
- }
- /* Get the value of register INDEX as saved in CONTEXT. */
- inline _Unwind_Word
- _Unwind_GetGR (struct _Unwind_Context *context, int index)
- {
- int size;
- _Unwind_Context_Reg_Val val;
- #ifdef DWARF_ZERO_REG
- if (index == DWARF_ZERO_REG)
- return 0;
- #endif
- index = DWARF_REG_TO_UNWIND_COLUMN (index);
- gcc_assert (index < (int) sizeof(dwarf_reg_size_table));
- size = dwarf_reg_size_table[index];
- val = context->reg[index];
- if (_Unwind_IsExtendedContext (context) && context->by_value[index])
- return _Unwind_Get_Unwind_Word (val);
- /* This will segfault if the register hasn't been saved. */
- if (size == sizeof(_Unwind_Ptr))
- return * (_Unwind_Ptr *) (_Unwind_Internal_Ptr) val;
- else
- {
- gcc_assert (size == sizeof(_Unwind_Word));
- return * (_Unwind_Word *) (_Unwind_Internal_Ptr) val;
- }
- }
- static inline void *
- _Unwind_GetPtr (struct _Unwind_Context *context, int index)
- {
- return (void *)(_Unwind_Ptr) _Unwind_GetGR (context, index);
- }
- /* Get the value of the CFA as saved in CONTEXT. */
- _Unwind_Word
- _Unwind_GetCFA (struct _Unwind_Context *context)
- {
- return (_Unwind_Ptr) context->cfa;
- }
- /* Overwrite the saved value for register INDEX in CONTEXT with VAL. */
- inline void
- _Unwind_SetGR (struct _Unwind_Context *context, int index, _Unwind_Word val)
- {
- int size;
- void *ptr;
- index = DWARF_REG_TO_UNWIND_COLUMN (index);
- gcc_assert (index < (int) sizeof(dwarf_reg_size_table));
- size = dwarf_reg_size_table[index];
- if (_Unwind_IsExtendedContext (context) && context->by_value[index])
- {
- context->reg[index] = _Unwind_Get_Unwind_Context_Reg_Val (val);
- return;
- }
- ptr = (void *) (_Unwind_Internal_Ptr) context->reg[index];
- if (size == sizeof(_Unwind_Ptr))
- * (_Unwind_Ptr *) ptr = val;
- else
- {
- #if defined( __CR16C__ )
- if (size == sizeof(_Unwind_Word))
- * (_Unwind_Word *) ptr = val;
- else
- {
- typedef unsigned _CR16_Unwind_Word __attribute__((__mode__(__word__)));
- gcc_assert (index + 1 < (int) sizeof(dwarf_reg_size_table));
- * (_CR16_Unwind_Word *) ptr = val & 0xffff ; /* low 16-bit */
- ptr = context->reg[index + 1];
- * (_CR16_Unwind_Word *) ptr = val >> 16 ; /* high 16-bit */
- }
- #else
- gcc_assert (size == sizeof(_Unwind_Word));
- * (_Unwind_Word *) ptr = val;
- #endif
- }
- }
- /* Get the pointer to a register INDEX as saved in CONTEXT. */
- static inline void *
- _Unwind_GetGRPtr (struct _Unwind_Context *context, int index)
- {
- index = DWARF_REG_TO_UNWIND_COLUMN (index);
- if (_Unwind_IsExtendedContext (context) && context->by_value[index])
- return &context->reg[index];
- return (void *) (_Unwind_Internal_Ptr) context->reg[index];
- }
- /* Set the pointer to a register INDEX as saved in CONTEXT. */
- static inline void
- _Unwind_SetGRPtr (struct _Unwind_Context *context, int index, void *p)
- {
- index = DWARF_REG_TO_UNWIND_COLUMN (index);
- if (_Unwind_IsExtendedContext (context))
- context->by_value[index] = 0;
- context->reg[index] = (_Unwind_Context_Reg_Val) (_Unwind_Internal_Ptr) p;
- }
- /* Overwrite the saved value for register INDEX in CONTEXT with VAL. */
- static inline void
- _Unwind_SetGRValue (struct _Unwind_Context *context, int index,
- _Unwind_Word val)
- {
- index = DWARF_REG_TO_UNWIND_COLUMN (index);
- gcc_assert (index < (int) sizeof(dwarf_reg_size_table));
- gcc_assert (dwarf_reg_size_table[index] == sizeof (_Unwind_Context_Reg_Val));
- context->by_value[index] = 1;
- context->reg[index] = _Unwind_Get_Unwind_Context_Reg_Val (val);
- }
- /* Return nonzero if register INDEX is stored by value rather than
- by reference. */
- static inline int
- _Unwind_GRByValue (struct _Unwind_Context *context, int index)
- {
- index = DWARF_REG_TO_UNWIND_COLUMN (index);
- return context->by_value[index];
- }
- /* Retrieve the return address for CONTEXT. */
- inline _Unwind_Ptr
- _Unwind_GetIP (struct _Unwind_Context *context)
- {
- return (_Unwind_Ptr) context->ra;
- }
- /* Retrieve the return address and flag whether that IP is before
- or after first not yet fully executed instruction. */
- inline _Unwind_Ptr
- _Unwind_GetIPInfo (struct _Unwind_Context *context, int *ip_before_insn)
- {
- *ip_before_insn = _Unwind_IsSignalFrame (context);
- return (_Unwind_Ptr) context->ra;
- }
- /* Overwrite the return address for CONTEXT with VAL. */
- inline void
- _Unwind_SetIP (struct _Unwind_Context *context, _Unwind_Ptr val)
- {
- context->ra = (void *) val;
- }
- void *
- _Unwind_GetLanguageSpecificData (struct _Unwind_Context *context)
- {
- return context->lsda;
- }
- _Unwind_Ptr
- _Unwind_GetRegionStart (struct _Unwind_Context *context)
- {
- return (_Unwind_Ptr) context->bases.func;
- }
- void *
- _Unwind_FindEnclosingFunction (void *pc)
- {
- struct dwarf_eh_bases bases;
- const struct dwarf_fde *fde = _Unwind_Find_FDE (pc-1, &bases);
- if (fde)
- return bases.func;
- else
- return NULL;
- }
- _Unwind_Ptr
- _Unwind_GetDataRelBase (struct _Unwind_Context *context)
- {
- return (_Unwind_Ptr) context->bases.dbase;
- }
- _Unwind_Ptr
- _Unwind_GetTextRelBase (struct _Unwind_Context *context)
- {
- return (_Unwind_Ptr) context->bases.tbase;
- }
- #include "md-unwind-support.h"
- /* Extract any interesting information from the CIE for the translation
- unit F belongs to. Return a pointer to the byte after the augmentation,
- or NULL if we encountered an undecipherable augmentation. */
- static const unsigned char *
- extract_cie_info (const struct dwarf_cie *cie, struct _Unwind_Context *context,
- _Unwind_FrameState *fs)
- {
- const unsigned char *aug = cie->augmentation;
- const unsigned char *p = aug + strlen ((const char *)aug) + 1;
- const unsigned char *ret = NULL;
- _uleb128_t utmp;
- _sleb128_t stmp;
- /* g++ v2 "eh" has pointer immediately following augmentation string,
- so it must be handled first. */
- if (aug[0] == 'e' && aug[1] == 'h')
- {
- fs->eh_ptr = read_pointer (p);
- p += sizeof (void *);
- aug += 2;
- }
- /* After the augmentation resp. pointer for "eh" augmentation
- follows for CIE version >= 4 address size byte and
- segment size byte. */
- if (__builtin_expect (cie->version >= 4, 0))
- {
- if (p[0] != sizeof (void *) || p[1] != 0)
- return NULL;
- p += 2;
- }
- /* Immediately following this are the code and
- data alignment and return address column. */
- p = read_uleb128 (p, &utmp);
- fs->code_align = (_Unwind_Word)utmp;
- p = read_sleb128 (p, &stmp);
- fs->data_align = (_Unwind_Sword)stmp;
- if (cie->version == 1)
- fs->retaddr_column = *p++;
- else
- {
- p = read_uleb128 (p, &utmp);
- fs->retaddr_column = (_Unwind_Word)utmp;
- }
- fs->lsda_encoding = DW_EH_PE_omit;
- /* If the augmentation starts with 'z', then a uleb128 immediately
- follows containing the length of the augmentation field following
- the size. */
- if (*aug == 'z')
- {
- p = read_uleb128 (p, &utmp);
- ret = p + utmp;
- fs->saw_z = 1;
- ++aug;
- }
- /* Iterate over recognized augmentation subsequences. */
- while (*aug != '\0')
- {
- /* "L" indicates a byte showing how the LSDA pointer is encoded. */
- if (aug[0] == 'L')
- {
- fs->lsda_encoding = *p++;
- aug += 1;
- }
- /* "R" indicates a byte indicating how FDE addresses are encoded. */
- else if (aug[0] == 'R')
- {
- fs->fde_encoding = *p++;
- aug += 1;
- }
- /* "P" indicates a personality routine in the CIE augmentation. */
- else if (aug[0] == 'P')
- {
- _Unwind_Ptr personality;
- p = read_encoded_value (context, *p, p + 1, &personality);
- fs->personality = (_Unwind_Personality_Fn) personality;
- aug += 1;
- }
- /* "S" indicates a signal frame. */
- else if (aug[0] == 'S')
- {
- fs->signal_frame = 1;
- aug += 1;
- }
- /* Otherwise we have an unknown augmentation string.
- Bail unless we saw a 'z' prefix. */
- else
- return ret;
- }
- return ret ? ret : p;
- }
- /* Decode a DW_OP stack program. Return the top of stack. Push INITIAL
- onto the stack to start. */
- static _Unwind_Word
- execute_stack_op (const unsigned char *op_ptr, const unsigned char *op_end,
- struct _Unwind_Context *context, _Unwind_Word initial)
- {
- _Unwind_Word stack[64]; /* ??? Assume this is enough. */
- int stack_elt;
- stack[0] = initial;
- stack_elt = 1;
- while (op_ptr < op_end)
- {
- enum dwarf_location_atom op = *op_ptr++;
- _Unwind_Word result;
- _uleb128_t reg, utmp;
- _sleb128_t offset, stmp;
- switch (op)
- {
- case DW_OP_lit0:
- case DW_OP_lit1:
- case DW_OP_lit2:
- case DW_OP_lit3:
- case DW_OP_lit4:
- case DW_OP_lit5:
- case DW_OP_lit6:
- case DW_OP_lit7:
- case DW_OP_lit8:
- case DW_OP_lit9:
- case DW_OP_lit10:
- case DW_OP_lit11:
- case DW_OP_lit12:
- case DW_OP_lit13:
- case DW_OP_lit14:
- case DW_OP_lit15:
- case DW_OP_lit16:
- case DW_OP_lit17:
- case DW_OP_lit18:
- case DW_OP_lit19:
- case DW_OP_lit20:
- case DW_OP_lit21:
- case DW_OP_lit22:
- case DW_OP_lit23:
- case DW_OP_lit24:
- case DW_OP_lit25:
- case DW_OP_lit26:
- case DW_OP_lit27:
- case DW_OP_lit28:
- case DW_OP_lit29:
- case DW_OP_lit30:
- case DW_OP_lit31:
- result = op - DW_OP_lit0;
- break;
- case DW_OP_addr:
- result = (_Unwind_Word) (_Unwind_Ptr) read_pointer (op_ptr);
- op_ptr += sizeof (void *);
- break;
- case DW_OP_GNU_encoded_addr:
- {
- _Unwind_Ptr presult;
- op_ptr = read_encoded_value (context, *op_ptr, op_ptr+1, &presult);
- result = presult;
- }
- break;
- case DW_OP_const1u:
- result = read_1u (op_ptr);
- op_ptr += 1;
- break;
- case DW_OP_const1s:
- result = read_1s (op_ptr);
- op_ptr += 1;
- break;
- case DW_OP_const2u:
- result = read_2u (op_ptr);
- op_ptr += 2;
- break;
- case DW_OP_const2s:
- result = read_2s (op_ptr);
- op_ptr += 2;
- break;
- case DW_OP_const4u:
- result = read_4u (op_ptr);
- op_ptr += 4;
- break;
- case DW_OP_const4s:
- result = read_4s (op_ptr);
- op_ptr += 4;
- break;
- case DW_OP_const8u:
- result = read_8u (op_ptr);
- op_ptr += 8;
- break;
- case DW_OP_const8s:
- result = read_8s (op_ptr);
- op_ptr += 8;
- break;
- case DW_OP_constu:
- op_ptr = read_uleb128 (op_ptr, &utmp);
- result = (_Unwind_Word)utmp;
- break;
- case DW_OP_consts:
- op_ptr = read_sleb128 (op_ptr, &stmp);
- result = (_Unwind_Sword)stmp;
- break;
- case DW_OP_reg0:
- case DW_OP_reg1:
- case DW_OP_reg2:
- case DW_OP_reg3:
- case DW_OP_reg4:
- case DW_OP_reg5:
- case DW_OP_reg6:
- case DW_OP_reg7:
- case DW_OP_reg8:
- case DW_OP_reg9:
- case DW_OP_reg10:
- case DW_OP_reg11:
- case DW_OP_reg12:
- case DW_OP_reg13:
- case DW_OP_reg14:
- case DW_OP_reg15:
- case DW_OP_reg16:
- case DW_OP_reg17:
- case DW_OP_reg18:
- case DW_OP_reg19:
- case DW_OP_reg20:
- case DW_OP_reg21:
- case DW_OP_reg22:
- case DW_OP_reg23:
- case DW_OP_reg24:
- case DW_OP_reg25:
- case DW_OP_reg26:
- case DW_OP_reg27:
- case DW_OP_reg28:
- case DW_OP_reg29:
- case DW_OP_reg30:
- case DW_OP_reg31:
- result = _Unwind_GetGR (context, op - DW_OP_reg0);
- break;
- case DW_OP_regx:
- op_ptr = read_uleb128 (op_ptr, ®);
- result = _Unwind_GetGR (context, reg);
- break;
- case DW_OP_breg0:
- case DW_OP_breg1:
- case DW_OP_breg2:
- case DW_OP_breg3:
- case DW_OP_breg4:
- case DW_OP_breg5:
- case DW_OP_breg6:
- case DW_OP_breg7:
- case DW_OP_breg8:
- case DW_OP_breg9:
- case DW_OP_breg10:
- case DW_OP_breg11:
- case DW_OP_breg12:
- case DW_OP_breg13:
- case DW_OP_breg14:
- case DW_OP_breg15:
- case DW_OP_breg16:
- case DW_OP_breg17:
- case DW_OP_breg18:
- case DW_OP_breg19:
- case DW_OP_breg20:
- case DW_OP_breg21:
- case DW_OP_breg22:
- case DW_OP_breg23:
- case DW_OP_breg24:
- case DW_OP_breg25:
- case DW_OP_breg26:
- case DW_OP_breg27:
- case DW_OP_breg28:
- case DW_OP_breg29:
- case DW_OP_breg30:
- case DW_OP_breg31:
- op_ptr = read_sleb128 (op_ptr, &offset);
- result = _Unwind_GetGR (context, op - DW_OP_breg0) + offset;
- break;
- case DW_OP_bregx:
- op_ptr = read_uleb128 (op_ptr, ®);
- op_ptr = read_sleb128 (op_ptr, &offset);
- result = _Unwind_GetGR (context, reg) + (_Unwind_Word)offset;
- break;
- case DW_OP_dup:
- gcc_assert (stack_elt);
- result = stack[stack_elt - 1];
- break;
- case DW_OP_drop:
- gcc_assert (stack_elt);
- stack_elt -= 1;
- goto no_push;
- case DW_OP_pick:
- offset = *op_ptr++;
- gcc_assert (offset < stack_elt - 1);
- result = stack[stack_elt - 1 - offset];
- break;
- case DW_OP_over:
- gcc_assert (stack_elt >= 2);
- result = stack[stack_elt - 2];
- break;
- case DW_OP_swap:
- {
- _Unwind_Word t;
- gcc_assert (stack_elt >= 2);
- t = stack[stack_elt - 1];
- stack[stack_elt - 1] = stack[stack_elt - 2];
- stack[stack_elt - 2] = t;
- goto no_push;
- }
- case DW_OP_rot:
- {
- _Unwind_Word t1, t2, t3;
- gcc_assert (stack_elt >= 3);
- t1 = stack[stack_elt - 1];
- t2 = stack[stack_elt - 2];
- t3 = stack[stack_elt - 3];
- stack[stack_elt - 1] = t2;
- stack[stack_elt - 2] = t3;
- stack[stack_elt - 3] = t1;
- goto no_push;
- }
- case DW_OP_deref:
- case DW_OP_deref_size:
- case DW_OP_abs:
- case DW_OP_neg:
- case DW_OP_not:
- case DW_OP_plus_uconst:
- /* Unary operations. */
- gcc_assert (stack_elt);
- stack_elt -= 1;
- result = stack[stack_elt];
- switch (op)
- {
- case DW_OP_deref:
- {
- void *ptr = (void *) (_Unwind_Ptr) result;
- result = (_Unwind_Ptr) read_pointer (ptr);
- }
- break;
- case DW_OP_deref_size:
- {
- void *ptr = (void *) (_Unwind_Ptr) result;
- switch (*op_ptr++)
- {
- case 1:
- result = read_1u (ptr);
- break;
- case 2:
- result = read_2u (ptr);
- break;
- case 4:
- result = read_4u (ptr);
- break;
- case 8:
- result = read_8u (ptr);
- break;
- default:
- gcc_unreachable ();
- }
- }
- break;
- case DW_OP_abs:
- if ((_Unwind_Sword) result < 0)
- result = -result;
- break;
- case DW_OP_neg:
- result = -result;
- break;
- case DW_OP_not:
- result = ~result;
- break;
- case DW_OP_plus_uconst:
- op_ptr = read_uleb128 (op_ptr, &utmp);
- result += (_Unwind_Word)utmp;
- break;
- default:
- gcc_unreachable ();
- }
- break;
- case DW_OP_and:
- case DW_OP_div:
- case DW_OP_minus:
- case DW_OP_mod:
- case DW_OP_mul:
- case DW_OP_or:
- case DW_OP_plus:
- case DW_OP_shl:
- case DW_OP_shr:
- case DW_OP_shra:
- case DW_OP_xor:
- case DW_OP_le:
- case DW_OP_ge:
- case DW_OP_eq:
- case DW_OP_lt:
- case DW_OP_gt:
- case DW_OP_ne:
- {
- /* Binary operations. */
- _Unwind_Word first, second;
- gcc_assert (stack_elt >= 2);
- stack_elt -= 2;
- second = stack[stack_elt];
- first = stack[stack_elt + 1];
- switch (op)
- {
- case DW_OP_and:
- result = second & first;
- break;
- case DW_OP_div:
- result = (_Unwind_Sword) second / (_Unwind_Sword) first;
- break;
- case DW_OP_minus:
- result = second - first;
- break;
- case DW_OP_mod:
- result = second % first;
- break;
- case DW_OP_mul:
- result = second * first;
- break;
- case DW_OP_or:
- result = second | first;
- break;
- case DW_OP_plus:
- result = second + first;
- break;
- case DW_OP_shl:
- result = second << first;
- break;
- case DW_OP_shr:
- result = second >> first;
- break;
- case DW_OP_shra:
- result = (_Unwind_Sword) second >> first;
- break;
- case DW_OP_xor:
- result = second ^ first;
- break;
- case DW_OP_le:
- result = (_Unwind_Sword) second <= (_Unwind_Sword) first;
- break;
- case DW_OP_ge:
- result = (_Unwind_Sword) second >= (_Unwind_Sword) first;
- break;
- case DW_OP_eq:
- result = (_Unwind_Sword) second == (_Unwind_Sword) first;
- break;
- case DW_OP_lt:
- result = (_Unwind_Sword) second < (_Unwind_Sword) first;
- break;
- case DW_OP_gt:
- result = (_Unwind_Sword) second > (_Unwind_Sword) first;
- break;
- case DW_OP_ne:
- result = (_Unwind_Sword) second != (_Unwind_Sword) first;
- break;
- default:
- gcc_unreachable ();
- }
- }
- break;
- case DW_OP_skip:
- offset = read_2s (op_ptr);
- op_ptr += 2;
- op_ptr += offset;
- goto no_push;
- case DW_OP_bra:
- gcc_assert (stack_elt);
- stack_elt -= 1;
- offset = read_2s (op_ptr);
- op_ptr += 2;
- if (stack[stack_elt] != 0)
- op_ptr += offset;
- goto no_push;
- case DW_OP_nop:
- goto no_push;
- default:
- gcc_unreachable ();
- }
- /* Most things push a result value. */
- gcc_assert ((size_t) stack_elt < sizeof(stack)/sizeof(*stack));
- stack[stack_elt++] = result;
- no_push:;
- }
- /* We were executing this program to get a value. It should be
- at top of stack. */
- gcc_assert (stack_elt);
- stack_elt -= 1;
- return stack[stack_elt];
- }
- /* Decode DWARF 2 call frame information. Takes pointers the
- instruction sequence to decode, current register information and
- CIE info, and the PC range to evaluate. */
- static void
- execute_cfa_program (const unsigned char *insn_ptr,
- const unsigned char *insn_end,
- struct _Unwind_Context *context,
- _Unwind_FrameState *fs)
- {
- struct frame_state_reg_info *unused_rs = NULL;
- /* Don't allow remember/restore between CIE and FDE programs. */
- fs->regs.prev = NULL;
- /* The comparison with the return address uses < rather than <= because
- we are only interested in the effects of code before the call; for a
- noreturn function, the return address may point to unrelated code with
- a different stack configuration that we are not interested in. We
- assume that the call itself is unwind info-neutral; if not, or if
- there are delay instructions that adjust the stack, these must be
- reflected at the point immediately before the call insn.
- In signal frames, return address is after last completed instruction,
- so we add 1 to return address to make the comparison <=. */
- while (insn_ptr < insn_end
- && fs->pc < context->ra + _Unwind_IsSignalFrame (context))
- {
- unsigned char insn = *insn_ptr++;
- _uleb128_t reg, utmp;
- _sleb128_t offset, stmp;
- if ((insn & 0xc0) == DW_CFA_advance_loc)
- fs->pc += (insn & 0x3f) * fs->code_align;
- else if ((insn & 0xc0) == DW_CFA_offset)
- {
- reg = insn & 0x3f;
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- offset = (_Unwind_Sword) utmp * fs->data_align;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].how
- = REG_SAVED_OFFSET;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].loc.offset = offset;
- }
- else if ((insn & 0xc0) == DW_CFA_restore)
- {
- reg = insn & 0x3f;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].how = REG_UNSAVED;
- }
- else switch (insn)
- {
- case DW_CFA_set_loc:
- {
- _Unwind_Ptr pc;
- insn_ptr = read_encoded_value (context, fs->fde_encoding,
- insn_ptr, &pc);
- fs->pc = (void *) pc;
- }
- break;
- case DW_CFA_advance_loc1:
- fs->pc += read_1u (insn_ptr) * fs->code_align;
- insn_ptr += 1;
- break;
- case DW_CFA_advance_loc2:
- fs->pc += read_2u (insn_ptr) * fs->code_align;
- insn_ptr += 2;
- break;
- case DW_CFA_advance_loc4:
- fs->pc += read_4u (insn_ptr) * fs->code_align;
- insn_ptr += 4;
- break;
- case DW_CFA_offset_extended:
- insn_ptr = read_uleb128 (insn_ptr, ®);
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- offset = (_Unwind_Sword) utmp * fs->data_align;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].how
- = REG_SAVED_OFFSET;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].loc.offset = offset;
- break;
- case DW_CFA_restore_extended:
- insn_ptr = read_uleb128 (insn_ptr, ®);
- /* FIXME, this is wrong; the CIE might have said that the
- register was saved somewhere. */
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN(reg)].how = REG_UNSAVED;
- break;
- case DW_CFA_same_value:
- insn_ptr = read_uleb128 (insn_ptr, ®);
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN(reg)].how = REG_UNSAVED;
- break;
- case DW_CFA_undefined:
- insn_ptr = read_uleb128 (insn_ptr, ®);
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN(reg)].how = REG_UNDEFINED;
- break;
- case DW_CFA_nop:
- break;
- case DW_CFA_register:
- {
- _uleb128_t reg2;
- insn_ptr = read_uleb128 (insn_ptr, ®);
- insn_ptr = read_uleb128 (insn_ptr, ®2);
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].how = REG_SAVED_REG;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].loc.reg =
- (_Unwind_Word)reg2;
- }
- break;
- case DW_CFA_remember_state:
- {
- struct frame_state_reg_info *new_rs;
- if (unused_rs)
- {
- new_rs = unused_rs;
- unused_rs = unused_rs->prev;
- }
- else
- new_rs = alloca (sizeof (struct frame_state_reg_info));
- *new_rs = fs->regs;
- fs->regs.prev = new_rs;
- }
- break;
- case DW_CFA_restore_state:
- {
- struct frame_state_reg_info *old_rs = fs->regs.prev;
- fs->regs = *old_rs;
- old_rs->prev = unused_rs;
- unused_rs = old_rs;
- }
- break;
- case DW_CFA_def_cfa:
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- fs->regs.cfa_reg = (_Unwind_Word)utmp;
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- fs->regs.cfa_offset = (_Unwind_Word)utmp;
- fs->regs.cfa_how = CFA_REG_OFFSET;
- break;
- case DW_CFA_def_cfa_register:
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- fs->regs.cfa_reg = (_Unwind_Word)utmp;
- fs->regs.cfa_how = CFA_REG_OFFSET;
- break;
- case DW_CFA_def_cfa_offset:
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- fs->regs.cfa_offset = utmp;
- /* cfa_how deliberately not set. */
- break;
- case DW_CFA_def_cfa_expression:
- fs->regs.cfa_exp = insn_ptr;
- fs->regs.cfa_how = CFA_EXP;
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- insn_ptr += utmp;
- break;
- case DW_CFA_expression:
- insn_ptr = read_uleb128 (insn_ptr, ®);
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].how = REG_SAVED_EXP;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].loc.exp = insn_ptr;
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- insn_ptr += utmp;
- break;
- /* Dwarf3. */
- case DW_CFA_offset_extended_sf:
- insn_ptr = read_uleb128 (insn_ptr, ®);
- insn_ptr = read_sleb128 (insn_ptr, &stmp);
- offset = stmp * fs->data_align;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].how
- = REG_SAVED_OFFSET;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].loc.offset = offset;
- break;
- case DW_CFA_def_cfa_sf:
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- fs->regs.cfa_reg = (_Unwind_Word)utmp;
- insn_ptr = read_sleb128 (insn_ptr, &stmp);
- fs->regs.cfa_offset = (_Unwind_Sword)stmp;
- fs->regs.cfa_how = CFA_REG_OFFSET;
- fs->regs.cfa_offset *= fs->data_align;
- break;
- case DW_CFA_def_cfa_offset_sf:
- insn_ptr = read_sleb128 (insn_ptr, &stmp);
- fs->regs.cfa_offset = (_Unwind_Sword)stmp;
- fs->regs.cfa_offset *= fs->data_align;
- /* cfa_how deliberately not set. */
- break;
- case DW_CFA_val_offset:
- insn_ptr = read_uleb128 (insn_ptr, ®);
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- offset = (_Unwind_Sword) utmp * fs->data_align;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].how
- = REG_SAVED_VAL_OFFSET;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].loc.offset = offset;
- break;
- case DW_CFA_val_offset_sf:
- insn_ptr = read_uleb128 (insn_ptr, ®);
- insn_ptr = read_sleb128 (insn_ptr, &stmp);
- offset = stmp * fs->data_align;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].how
- = REG_SAVED_VAL_OFFSET;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].loc.offset = offset;
- break;
- case DW_CFA_val_expression:
- insn_ptr = read_uleb128 (insn_ptr, ®);
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].how
- = REG_SAVED_VAL_EXP;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].loc.exp = insn_ptr;
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- insn_ptr += utmp;
- break;
- case DW_CFA_GNU_window_save:
- /* ??? Hardcoded for SPARC register window configuration. */
- for (reg = 16; reg < 32; ++reg)
- {
- fs->regs.reg[reg].how = REG_SAVED_OFFSET;
- fs->regs.reg[reg].loc.offset = (reg - 16) * sizeof (void *);
- }
- break;
- case DW_CFA_GNU_args_size:
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- context->args_size = (_Unwind_Word)utmp;
- break;
- case DW_CFA_GNU_negative_offset_extended:
- /* Obsoleted by DW_CFA_offset_extended_sf, but used by
- older PowerPC code. */
- insn_ptr = read_uleb128 (insn_ptr, ®);
- insn_ptr = read_uleb128 (insn_ptr, &utmp);
- offset = (_Unwind_Word) utmp * fs->data_align;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].how
- = REG_SAVED_OFFSET;
- fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (reg)].loc.offset = -offset;
- break;
- default:
- gcc_unreachable ();
- }
- }
- }
- /* Given the _Unwind_Context CONTEXT for a stack frame, look up the FDE for
- its caller and decode it into FS. This function also sets the
- args_size and lsda members of CONTEXT, as they are really information
- about the caller's frame. */
- static _Unwind_Reason_Code
- uw_frame_state_for (struct _Unwind_Context *context, _Unwind_FrameState *fs)
- {
- const struct dwarf_fde *fde;
- const struct dwarf_cie *cie;
- const unsigned char *aug, *insn, *end;
- memset (fs, 0, sizeof (*fs));
- context->args_size = 0;
- context->lsda = 0;
- if (context->ra == 0)
- return _URC_END_OF_STACK;
- fde = _Unwind_Find_FDE (context->ra + _Unwind_IsSignalFrame (context) - 1,
- &context->bases);
- if (fde == NULL)
- {
- #ifdef MD_FALLBACK_FRAME_STATE_FOR
- /* Couldn't find frame unwind info for this function. Try a
- target-specific fallback mechanism. This will necessarily
- not provide a personality routine or LSDA. */
- return MD_FALLBACK_FRAME_STATE_FOR (context, fs);
- #else
- return _URC_END_OF_STACK;
- #endif
- }
- fs->pc = context->bases.func;
- cie = get_cie (fde);
- insn = extract_cie_info (cie, context, fs);
- if (insn == NULL)
- /* CIE contained unknown augmentation. */
- return _URC_FATAL_PHASE1_ERROR;
- /* First decode all the insns in the CIE. */
- end = (const unsigned char *) next_fde ((const struct dwarf_fde *) cie);
- execute_cfa_program (insn, end, context, fs);
- /* Locate augmentation for the fde. */
- aug = (const unsigned char *) fde + sizeof (*fde);
- aug += 2 * size_of_encoded_value (fs->fde_encoding);
- insn = NULL;
- if (fs->saw_z)
- {
- _uleb128_t i;
- aug = read_uleb128 (aug, &i);
- insn = aug + i;
- }
- if (fs->lsda_encoding != DW_EH_PE_omit)
- {
- _Unwind_Ptr lsda;
- aug = read_encoded_value (context, fs->lsda_encoding, aug, &lsda);
- context->lsda = (void *) lsda;
- }
- /* Then the insns in the FDE up to our target PC. */
- if (insn == NULL)
- insn = aug;
- end = (const unsigned char *) next_fde (fde);
- execute_cfa_program (insn, end, context, fs);
- return _URC_NO_REASON;
- }
- typedef struct frame_state
- {
- void *cfa;
- void *eh_ptr;
- long cfa_offset;
- long args_size;
- long reg_or_offset[PRE_GCC3_DWARF_FRAME_REGISTERS+1];
- unsigned short cfa_reg;
- unsigned short retaddr_column;
- char saved[PRE_GCC3_DWARF_FRAME_REGISTERS+1];
- } frame_state;
- struct frame_state * __frame_state_for (void *, struct frame_state *);
- /* Called from pre-G++ 3.0 __throw to find the registers to restore for
- a given PC_TARGET. The caller should allocate a local variable of
- `struct frame_state' and pass its address to STATE_IN. */
- struct frame_state *
- __frame_state_for (void *pc_target, struct frame_state *state_in)
- {
- struct _Unwind_Context context;
- _Unwind_FrameState fs;
- int reg;
- memset (&context, 0, sizeof (struct _Unwind_Context));
- if (!ASSUME_EXTENDED_UNWIND_CONTEXT)
- context.flags = EXTENDED_CONTEXT_BIT;
- context.ra = pc_target + 1;
- if (uw_frame_state_for (&context, &fs) != _URC_NO_REASON)
- return 0;
- /* We have no way to pass a location expression for the CFA to our
- caller. It wouldn't understand it anyway. */
- if (fs.regs.cfa_how == CFA_EXP)
- return 0;
- for (reg = 0; reg < PRE_GCC3_DWARF_FRAME_REGISTERS + 1; reg++)
- {
- state_in->saved[reg] = fs.regs.reg[reg].how;
- switch (state_in->saved[reg])
- {
- case REG_SAVED_REG:
- state_in->reg_or_offset[reg] = fs.regs.reg[reg].loc.reg;
- break;
- case REG_SAVED_OFFSET:
- state_in->reg_or_offset[reg] = fs.regs.reg[reg].loc.offset;
- break;
- default:
- state_in->reg_or_offset[reg] = 0;
- break;
- }
- }
- state_in->cfa_offset = fs.regs.cfa_offset;
- state_in->cfa_reg = fs.regs.cfa_reg;
- state_in->retaddr_column = fs.retaddr_column;
- state_in->args_size = context.args_size;
- state_in->eh_ptr = fs.eh_ptr;
- return state_in;
- }
- typedef union { _Unwind_Ptr ptr; _Unwind_Word word; } _Unwind_SpTmp;
- static inline void
- _Unwind_SetSpColumn (struct _Unwind_Context *context, void *cfa,
- _Unwind_SpTmp *tmp_sp)
- {
- int size = dwarf_reg_size_table[__builtin_dwarf_sp_column ()];
- if (size == sizeof(_Unwind_Ptr))
- tmp_sp->ptr = (_Unwind_Ptr) cfa;
- else
- {
- gcc_assert (size == sizeof(_Unwind_Word));
- tmp_sp->word = (_Unwind_Ptr) cfa;
- }
- _Unwind_SetGRPtr (context, __builtin_dwarf_sp_column (), tmp_sp);
- }
- static void
- uw_update_context_1 (struct _Unwind_Context *context, _Unwind_FrameState *fs)
- {
- struct _Unwind_Context orig_context = *context;
- void *cfa;
- long i;
- #ifdef __LIBGCC_EH_RETURN_STACKADJ_RTX__
- /* Special handling here: Many machines do not use a frame pointer,
- and track the CFA only through offsets from the stack pointer from
- one frame to the next. In this case, the stack pointer is never
- stored, so it has no saved address in the context. What we do
- have is the CFA from the previous stack frame.
- In very special situations (such as unwind info for signal return),
- there may be location expressions that use the stack pointer as well.
- Do this conditionally for one frame. This allows the unwind info
- for one frame to save a copy of the stack pointer from the previous
- frame, and be able to use much easier CFA mechanisms to do it.
- Always zap the saved stack pointer value for the next frame; carrying
- the value over from one frame to another doesn't make sense. */
- _Unwind_SpTmp tmp_sp;
- if (!_Unwind_GetGRPtr (&orig_context, __builtin_dwarf_sp_column ()))
- _Unwind_SetSpColumn (&orig_context, context->cfa, &tmp_sp);
- _Unwind_SetGRPtr (context, __builtin_dwarf_sp_column (), NULL);
- #endif
- /* Compute this frame's CFA. */
- switch (fs->regs.cfa_how)
- {
- case CFA_REG_OFFSET:
- cfa = _Unwind_GetPtr (&orig_context, fs->regs.cfa_reg);
- cfa += fs->regs.cfa_offset;
- break;
- case CFA_EXP:
- {
- const unsigned char *exp = fs->regs.cfa_exp;
- _uleb128_t len;
- exp = read_uleb128 (exp, &len);
- cfa = (void *) (_Unwind_Ptr)
- execute_stack_op (exp, exp + len, &orig_context, 0);
- break;
- }
- default:
- gcc_unreachable ();
- }
- context->cfa = cfa;
- /* Compute the addresses of all registers saved in this frame. */
- for (i = 0; i < __LIBGCC_DWARF_FRAME_REGISTERS__ + 1; ++i)
- switch (fs->regs.reg[i].how)
- {
- case REG_UNSAVED:
- case REG_UNDEFINED:
- break;
- case REG_SAVED_OFFSET:
- _Unwind_SetGRPtr (context, i,
- (void *) (cfa + fs->regs.reg[i].loc.offset));
- break;
- case REG_SAVED_REG:
- if (_Unwind_GRByValue (&orig_context, fs->regs.reg[i].loc.reg))
- _Unwind_SetGRValue (context, i,
- _Unwind_GetGR (&orig_context,
- fs->regs.reg[i].loc.reg));
- else
- _Unwind_SetGRPtr (context, i,
- _Unwind_GetGRPtr (&orig_context,
- fs->regs.reg[i].loc.reg));
- break;
- case REG_SAVED_EXP:
- {
- const unsigned char *exp = fs->regs.reg[i].loc.exp;
- _uleb128_t len;
- _Unwind_Ptr val;
- exp = read_uleb128 (exp, &len);
- val = execute_stack_op (exp, exp + len, &orig_context,
- (_Unwind_Ptr) cfa);
- _Unwind_SetGRPtr (context, i, (void *) val);
- }
- break;
- case REG_SAVED_VAL_OFFSET:
- _Unwind_SetGRValue (context, i,
- (_Unwind_Internal_Ptr)
- (cfa + fs->regs.reg[i].loc.offset));
- break;
- case REG_SAVED_VAL_EXP:
- {
- const unsigned char *exp = fs->regs.reg[i].loc.exp;
- _uleb128_t len;
- _Unwind_Ptr val;
- exp = read_uleb128 (exp, &len);
- val = execute_stack_op (exp, exp + len, &orig_context,
- (_Unwind_Ptr) cfa);
- _Unwind_SetGRValue (context, i, val);
- }
- break;
- }
- _Unwind_SetSignalFrame (context, fs->signal_frame);
- #ifdef MD_FROB_UPDATE_CONTEXT
- MD_FROB_UPDATE_CONTEXT (context, fs);
- #endif
- }
- /* CONTEXT describes the unwind state for a frame, and FS describes the FDE
- of its caller. Update CONTEXT to refer to the caller as well. Note
- that the args_size and lsda members are not updated here, but later in
- uw_frame_state_for. */
- static void
- uw_update_context (struct _Unwind_Context *context, _Unwind_FrameState *fs)
- {
- uw_update_context_1 (context, fs);
- /* In general this unwinder doesn't make any distinction between
- undefined and same_value rule. Call-saved registers are assumed
- to have same_value rule by default and explicit undefined
- rule is handled like same_value. The only exception is
- DW_CFA_undefined on retaddr_column which is supposed to
- mark outermost frame in DWARF 3. */
- if (fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (fs->retaddr_column)].how
- == REG_UNDEFINED)
- /* uw_frame_state_for uses context->ra == 0 check to find outermost
- stack frame. */
- context->ra = 0;
- else
- /* Compute the return address now, since the return address column
- can change from frame to frame. */
- context->ra = __builtin_extract_return_addr
- (_Unwind_GetPtr (context, fs->retaddr_column));
- #if defined( __CR16C__ )
- context->ra = (void*)( ( (unsigned)context->ra ) << 1 ) ;
- #endif
- }
- static void
- uw_advance_context (struct _Unwind_Context *context, _Unwind_FrameState *fs)
- {
- uw_update_context (context, fs);
- }
- /* Fill in CONTEXT for top-of-stack. The only valid registers at this
- level will be the return address and the CFA. */
- #define uw_init_context(CONTEXT) \
- do \
- { \
- /* Do any necessary initialization to access arbitrary stack frames. \
- On the SPARC, this means flushing the register windows. */ \
- __builtin_unwind_init (); \
- uw_init_context_1 (CONTEXT, __builtin_dwarf_cfa (), \
- __builtin_return_address (0)); \
- } \
- while (0)
- static inline void
- init_dwarf_reg_size_table (void)
- {
- __builtin_init_dwarf_reg_size_table (dwarf_reg_size_table);
- }
- static void __attribute__((noinline))
- uw_init_context_1 (struct _Unwind_Context *context,
- void *outer_cfa, void *outer_ra)
- {
- void *ra = __builtin_extract_return_addr (__builtin_return_address (0));
- _Unwind_FrameState fs;
- _Unwind_SpTmp sp_slot;
- _Unwind_Reason_Code code;
- memset (context, 0, sizeof (struct _Unwind_Context));
- context->ra = ra;
- if (!ASSUME_EXTENDED_UNWIND_CONTEXT)
- context->flags = EXTENDED_CONTEXT_BIT;
- code = uw_frame_state_for (context, &fs);
- gcc_assert (code == _URC_NO_REASON);
- #if __GTHREADS
- {
- static __gthread_once_t once_regsizes = __GTHREAD_ONCE_INIT;
- if (__gthread_once (&once_regsizes, init_dwarf_reg_size_table) != 0
- && dwarf_reg_size_table[0] == 0)
- init_dwarf_reg_size_table ();
- }
- #else
- if (dwarf_reg_size_table[0] == 0)
- init_dwarf_reg_size_table ();
- #endif
- /* Force the frame state to use the known cfa value. */
- _Unwind_SetSpColumn (context, outer_cfa, &sp_slot);
- fs.regs.cfa_how = CFA_REG_OFFSET;
- fs.regs.cfa_reg = __builtin_dwarf_sp_column ();
- #if !defined( __CR16C__ )
- fs.regs.cfa_offset = 0;
- #else
- fs.regs.cfa_offset -= context->args_size ;
- #endif
- uw_update_context_1 (context, &fs);
- /* If the return address column was saved in a register in the
- initialization context, then we can't see it in the given
- call frame data. So have the initialization context tell us. */
- context->ra = __builtin_extract_return_addr (outer_ra);
- }
- static void _Unwind_DebugHook (void *, void *)
- __attribute__ ((__noinline__, __used__, __noclone__));
- /* This function is called during unwinding. It is intended as a hook
- for a debugger to intercept exceptions. CFA is the CFA of the
- target frame. HANDLER is the PC to which control will be
- transferred. */
- static void
- _Unwind_DebugHook (void *cfa __attribute__ ((__unused__)),
- void *handler __attribute__ ((__unused__)))
- {
- /* We only want to use stap probes starting with v3. Earlier
- versions added too much startup cost. */
- #if defined (HAVE_SYS_SDT_H) && defined (STAP_PROBE2) && _SDT_NOTE_TYPE >= 3
- STAP_PROBE2 (libgcc, unwind, cfa, handler);
- #else
- asm ("");
- #endif
- }
- /* Install TARGET into CURRENT so that we can return to it. This is a
- macro because __builtin_eh_return must be invoked in the context of
- our caller. */
- #if defined( __CR16C__ )
- #define uw_install_context(CURRENT, TARGET, FRAMES) \
- do \
- { \
- long offset = uw_install_context_1 ((CURRENT), (TARGET)); \
- void *handler = __builtin_frob_return_addr ((TARGET)->ra); \
- handler = (void*)( ( (unsigned)handler ) >> 1 ) ; \
- _Unwind_DebugHook ((TARGET)->cfa, handler); \
- __builtin_eh_return (offset, handler); \
- } \
- while (0)
- #else
- #define uw_install_context(CURRENT, TARGET, FRAMES) \
- do \
- { \
- long offset = uw_install_context_1 ((CURRENT), (TARGET)); \
- void *handler = __builtin_frob_return_addr ((TARGET)->ra); \
- _Unwind_DebugHook ((TARGET)->cfa, handler); \
- __builtin_eh_return (offset, handler); \
- } \
- while (0)
- #endif /* __CR16C__ */
- static long
- uw_install_context_1 (struct _Unwind_Context *current,
- struct _Unwind_Context *target)
- {
- long i;
- _Unwind_SpTmp sp_slot;
- /* If the target frame does not have a saved stack pointer,
- then set up the target's CFA. */
- if (!_Unwind_GetGRPtr (target, __builtin_dwarf_sp_column ()))
- _Unwind_SetSpColumn (target, target->cfa, &sp_slot);
- for (i = 0; i < __LIBGCC_DWARF_FRAME_REGISTERS__; ++i)
- {
- void *c = (void *) (_Unwind_Internal_Ptr) current->reg[i];
- void *t = (void *) (_Unwind_Internal_Ptr)target->reg[i];
- gcc_assert (current->by_value[i] == 0);
- if (target->by_value[i] && c)
- {
- _Unwind_Word w;
- _Unwind_Ptr p;
- if (dwarf_reg_size_table[i] == sizeof (_Unwind_Word))
- {
- w = (_Unwind_Internal_Ptr) t;
- memcpy (c, &w, sizeof (_Unwind_Word));
- }
- else
- {
- gcc_assert (dwarf_reg_size_table[i] == sizeof (_Unwind_Ptr));
- p = (_Unwind_Internal_Ptr) t;
- memcpy (c, &p, sizeof (_Unwind_Ptr));
- }
- }
- else if (t && c && t != c)
- memcpy (c, t, dwarf_reg_size_table[i]);
- }
- /* If the current frame doesn't have a saved stack pointer, then we
- need to rely on EH_RETURN_STACKADJ_RTX to get our target stack
- pointer value reloaded. */
- if (!_Unwind_GetGRPtr (current, __builtin_dwarf_sp_column ()))
- {
- void *target_cfa;
- target_cfa = _Unwind_GetPtr (target, __builtin_dwarf_sp_column ());
- /* We adjust SP by the difference between CURRENT and TARGET's CFA. */
- if (__LIBGCC_STACK_GROWS_DOWNWARD__)
- return target_cfa - current->cfa + target->args_size;
- else
- return current->cfa - target_cfa - target->args_size;
- }
- return 0;
- }
- static inline _Unwind_Ptr
- uw_identify_context (struct _Unwind_Context *context)
- {
- /* The CFA is not sufficient to disambiguate the context of a function
- interrupted by a signal before establishing its frame and the context
- of the signal itself. */
- if (__LIBGCC_STACK_GROWS_DOWNWARD__)
- return _Unwind_GetCFA (context) - _Unwind_IsSignalFrame (context);
- else
- return _Unwind_GetCFA (context) + _Unwind_IsSignalFrame (context);
- }
- #include "unwind.inc"
- #if defined (USE_GAS_SYMVER) && defined (SHARED) && defined (USE_LIBUNWIND_EXCEPTIONS)
- alias (_Unwind_Backtrace);
- alias (_Unwind_DeleteException);
- alias (_Unwind_FindEnclosingFunction);
- alias (_Unwind_ForcedUnwind);
- alias (_Unwind_GetDataRelBase);
- alias (_Unwind_GetTextRelBase);
- alias (_Unwind_GetCFA);
- alias (_Unwind_GetGR);
- alias (_Unwind_GetIP);
- alias (_Unwind_GetLanguageSpecificData);
- alias (_Unwind_GetRegionStart);
- alias (_Unwind_RaiseException);
- alias (_Unwind_Resume);
- alias (_Unwind_Resume_or_Rethrow);
- alias (_Unwind_SetGR);
- alias (_Unwind_SetIP);
- #endif
- #endif /* !USING_SJLJ_EXCEPTIONS */
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