MCL/sf/os/kernelhwsrv: comparison kernel/eka/compsupp/aehabi/unwinder.c

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+:a41df078684a
+/* unwinder.c
+*
+* Copyright 2002-2003 ARM Limited.
+*/
+/*
+Licence
+1. Subject to the provisions of clause 2, ARM hereby grants to LICENSEE a
+perpetual, non-exclusive, nontransferable, royalty free, worldwide licence
+to use this Example Implementation of Exception Handling solely for the
+purpose of developing, having developed, manufacturing, having
+manufactured, offering to sell, selling, supplying or otherwise
+distributing products which comply with the Exception Handling ABI for the
+ARM Architecture specification. All other rights are reserved to ARM or its
+licensors.
+2. THIS EXAMPLE IMPLEMENTATION OF EXCEPTION HANDLING  IS PROVIDED "AS IS"
+WITH NO WARRANTIES EXPRESS, IMPLIED OR STATUTORY, INCLUDING BUT NOT LIMITED
+TO ANY WARRANTY OF SATISFACTORY QUALITY, MERCHANTABILITY, NONINFRINGEMENT
+OR FITNESS FOR A PARTICULAR PURPOSE.
+*/
+/*
+* RCS $Revision: 1.16 $
+* Checkin $Date: 2003/10/23 13:57:39 $
+* Revising $Author: agrant $
+*/
+/* Language-independent unwinder implementation */
+/* This source file is compiled automatically by ARM's make system into
+* multiple object files. The source regions constituting object file
+* xxx.o are delimited by ifdef xxx_c / endif directives.
+*
+* The source regions currently marked are:
+* unwinder_c
+* unwind_activity_c
+*/
+#include <stddef.h>
+#include <stdlib.h>
+/* Environment: */
+#include "unwind_env.h"
+/* Language-independent unwinder declarations: */
+#include "unwinder.h"
+/* Define UNWIND_ACTIVITY_DIAGNOSTICS for printed information from _Unwind_Activity */
+/* Define VRS_DIAGNOSTICS for printed diagnostics about VRS operations */
+#if defined(VRS_DIAGNOSTICS) || defined(UNWIND_ACTIVITY_DIAGNOSTICS)
+extern int printf(const char *, ...);
+#endif
+#ifdef unwinder_c
+/* =========================                      ========================= */
+/* ========================= Virtual register set ========================= */
+/* =========================                      ========================= */
+/* The approach taken by this implementation is to use the real machine
+* registers to hold all but the values of core (integer)
+* registers. Consequently the implementation must use only the core
+* registers except when manipulating the virtual register set. Non-core
+* registers are saved only on first use, so the single implementation can
+* cope with execution on processors which lack certain registers.  The
+* registers as they were at the start of the propagation must be preserved
+* over phase 1 so that the machine state is correct at the start of phase
+* 2. This requires a copy to be taken (which can be stack allocated). During
+* a stack unwind (phase 1 or phase 2), the "current" virtual register set is
+* implemented as core register values held in a data structure, and non-core
+* register values held in the registers themselves. To ensure that all
+* original register values are available at the beginning of phase 2, the
+* core registers are saved in a second structure at the start of phase 1 and
+* the non-core registers are demand-saved into another part of the data
+* structure that holds the current core registers during the phase 1 stack
+* unwind.
+*/
+/* Extent to which the access routines are implemented:
+* _Unwind_VRS_Get and _Unwind_VRS_Set implement only access to the core registers.
+* _Unwind_VRS_Pop implements only popping of core, vfp and fpa registers.
+* There is no support here for the Intel WMMX registers, but space is nevertheless
+* reserved in the virtual register set structure to indicate whether demand-saving
+* of those registers is required (as they are unsupported, it never is). The space
+* costs nothing as it is required for alignment.
+* The level of supported functionality is compliant with the requirements of the
+* Exceptions ABI.
+*/
+typedef unsigned char bool;
+struct core_s  { uint32_t r[16]; };        /* core integer regs */
+struct vfp_s   { uint64_t vfp[16+1]; };    /* VFP registers saved in FSTMX format */
+/* Extra 2 words for the format word + unused  */
+struct fpa_reg { uint32_t word[3]; };
+struct fpa_s   { struct fpa_reg fpa[8]; }; /* FPA registers saved in SFM format */
+/* Phase 1 virtual register set includes demand-save areas */
+/* The phase 2 virtual register set must be a prefix of the phase 1 set */
+typedef struct phase1_virtual_register_set_s {
+/* demand_save flag == 1 means save the registers in the demand-save area */
+bool demand_save_vfp;
+bool demand_save_fpa;
+bool demand_save_wmmxd;
+bool demand_save_wmmxc;
+struct core_s core;      /* current core registers */
+struct vfp_s  vfp;       /* demand-saved vfp registers */
+struct fpa_s  fpa;       /* demand-saved fpa registers */
+} phase1_virtual_register_set;
+/* Phase 2 virtual register set has no demand-save areas */
+/* The phase 2 virtual register set must be a prefix of the phase 1 set */
+/* The assembly fragments for _Unwind_RaiseException and _Unwind_Resume create
+* a phase2_virtual_register_set_s by hand so be careful.
+*/
+typedef struct phase2_virtual_register_set_s {
+/* demand_save flag == 1 means save the registers in the demand-save area */
+/* Always 0 in phase 2 */
+bool demand_save_vfp;
+bool demand_save_fpa;
+bool demand_save_wmmxd;
+bool demand_save_wmmxc;
+struct core_s core;      /* current core registers */
+} phase2_virtual_register_set;
+/* -- Helper macros for the embedded assembly */
+#if defined(__TARGET_ARCH_5T) || defined(__TARGET_ARCH_5TXM) || defined(__TARGET_ARCH_5TE) || \
+defined(__TARGET_ARCH_6)  /* || ... */
+#define ARCH_5T_OR_LATER 1
+#else
+#define ARCH_5T_OR_LATER 0
+#endif
+#if defined(__APCS_INTERWORK) && !ARCH_5T_OR_LATER
+#define OLD_STYLE_INTERWORKING 1
+#else
+#define OLD_STYLE_INTERWORKING 0
+#endif
+#if defined(__TARGET_ARCH_4T) || defined(__TARGET_ARCH_4TXM) || ARCH_5T_OR_LATER
+#define HAVE_BX 1
+#else
+#define HAVE_BX 0
+#endif
+#if HAVE_BX
+#define RET_LR bx lr
+#else
+#define RET_LR mov pc,lr
+#endif
+/* ----- Routines: ----- */
+/* ----- Helper routines, private but external ----- */
+/* Note '%0' refers to local label '0' */
+__asm void __ARM_Unwind_VRS_VFPpreserve(void *vfpp)
+{
+/* Preserve the vfp registers in the passed memory */
+#ifdef __thumb
+#define MAYBE_SWITCH_TO_ARM_STATE SWITCH_TO_ARM_STATE
+#define MAYBE_CODE16 code16
+macro;
+SWITCH_TO_ARM_STATE;
+1
+align 4;
+2
+assert (%2 - %1) = 0;
+bx pc;
+nop;
+code32;
+mend;
+#else
+#define MAYBE_SWITCH_TO_ARM_STATE /* nothing */
+#define MAYBE_CODE16 /* nothing */
+#endif
+vfp_d0 CN 0;
+MAYBE_SWITCH_TO_ARM_STATE;
+stc   p11,vfp_d0,[r0],{0x21};  /* 0xec800b21  FSTMIAX r0,{d0-d15} */
+RET_LR;
+MAYBE_CODE16;
+}
+__asm void __ARM_Unwind_VRS_VFPrestore(void *vfpp)
+{
+/* Restore the vfp registers from the passed memory */
+vfp_d0 CN 0;
+MAYBE_SWITCH_TO_ARM_STATE;
+ldc   p11,vfp_d0,[r0],{0x21};  /* 0xec900b21  FLDMIAX r0,{d0-d15} */
+RET_LR;
+MAYBE_CODE16;
+}
+__asm void __ARM_Unwind_VRS_FPApreserve(void *vfpp)
+{
+/* Preserve the fpa registers in the passed memory */
+fpa_f0 CN 0;
+fpa_f4 CN 0;
+MAYBE_SWITCH_TO_ARM_STATE;
+stc   p2, fpa_f0, [r0];       /* 0xed800200  SFM f0,4,[r0,#0]    */
+stc   p2, fpa_f4, [r0, #48];  /* 0xed80420c  SFM f4,4,[r0,#0x30] */
+RET_LR;
+MAYBE_CODE16;
+}
+__asm void __ARM_Unwind_VRS_FPArestore(void *vfpp)
+{
+/* Restore the fpa registers from the passed memory */
+fpa_f0 CN 0;
+fpa_f4 CN 0;
+MAYBE_SWITCH_TO_ARM_STATE;
+ldc   p2, fpa_f0, [r0];       /* 0xed900200  LFM f0,4,[r0,#0]    */
+ldc   p2, fpa_f4, [r0, #48];  /* 0xed90020c  LFM f4,4,[r0,#0x30] */
+RET_LR;
+MAYBE_CODE16;
+}
+__asm NORETURNDECL void __ARM_Unwind_VRS_corerestore(void *corep)
+{
+/* By hypothesis this is preserve8 but the load of sp means the
+* assembler can't infer that.
+*/
+preserve8;
+MAYBE_SWITCH_TO_ARM_STATE;
+#if OLD_STYLE_INTERWORKING
+mov r14, r0;
+ldmia r14!,{r0-r12};
+ldr   r12,[r14, #4*2]; /* pc */
+ldmia r14,{r13-r14};
+bx    r12;
+#else
+ldmia r0,{r0-r15};
+#endif
+MAYBE_CODE16;
+}
+/* ----- Development support ----- */
+#ifdef VRS_DIAGNOSTICS
+static void debug_print_vrs_vfp(struct vfp_s *vfpp)
+{
+uint64_t *lp = (uint64_t *)vfpp;
+int c = 0;
+int i;
+for (i = 0; i < 16; i++) {
+printf("D%-2d  0x%16.16llx    ", i, *lp);
+lp++;
+if (c++ == 1) {
+c = 0;
+printf("\n");
+}
+}
+}
+static void debug_print_vrs_fpa(struct fpa_s *fpap)
+{
+uint32_t *lp = (uint32_t *)fpap;
+int c = 0;
+int i;
+for (i = 0; i < 8; i++) {
+printf("F%-2d  0x%8.8x%8.8x%8.8x    ", i, *lp, *(lp+1), *(lp+2));
+lp+=3;
+if (c++ == 1) {
+c = 0;
+printf("\n");
+}
+}
+}
+static void debug_print_vrs(_Unwind_Context *context)
+{
+phase1_virtual_register_set *vrsp = (phase1_virtual_register_set *)context;
+int i;
+int c;
+printf("------------------------------------------------------------------------\n");
+c = 0;
+for (i = 0; i < 16; i++) {
+printf("r%-2d  0x%8.8x    ", i, vrsp->core.r[i]);
+if (c++ == 3) {
+c = 0;
+printf("\n");
+}
+}
+printf("-----\n");
+if (vrsp->demand_save_vfp == 1)
+printf("VFP is not saved\n");
+else
+debug_print_vrs_vfp(&vrsp->vfp);
+printf("-----\n");
+if (vrsp->demand_save_fpa == 1)
+printf("FPA is not saved\n");
+else
+debug_print_vrs_fpa(&vrsp->fpa);
+printf("------------------------------------------------------------------------\n");
+}
+#endif
+/* ----- Public routines ----- */
+_Unwind_VRS_Result _Unwind_VRS_Set(_Unwind_Context *context,
+_Unwind_VRS_RegClass regclass,
+uint32_t regno,
+_Unwind_VRS_DataRepresentation representation,
+void *valuep)
+{
+phase1_virtual_register_set *vrsp = (phase1_virtual_register_set *)context;
+switch (regclass) {
+case _UVRSC_CORE:
+{
+if (representation != _UVRSD_UINT32 || regno > 15)
+return _UVRSR_FAILED;
+vrsp->core.r[regno] = *(uint32_t *)valuep;
+return _UVRSR_OK;
+}
+case _UVRSC_VFP:
+case _UVRSC_FPA:
+case _UVRSC_WMMXD:
+case _UVRSC_WMMXC:
+return _UVRSR_NOT_IMPLEMENTED;
+default:
+break;
+}
+return _UVRSR_FAILED;
+}
+_Unwind_VRS_Result _Unwind_VRS_Get(_Unwind_Context *context,
+_Unwind_VRS_RegClass regclass,
+uint32_t regno,
+_Unwind_VRS_DataRepresentation representation,
+void *valuep)
+{
+phase1_virtual_register_set *vrsp = (phase1_virtual_register_set *)context;
+switch (regclass) {
+case _UVRSC_CORE:
+{
+if (representation != _UVRSD_UINT32 || regno > 15)
+return _UVRSR_FAILED;
+*(uint32_t *)valuep = vrsp->core.r[regno];
+return _UVRSR_OK;
+}
+case _UVRSC_VFP:
+case _UVRSC_FPA:
+case _UVRSC_WMMXD:
+case _UVRSC_WMMXC:
+return _UVRSR_NOT_IMPLEMENTED;
+default:
+break;
+}
+return _UVRSR_FAILED;
+}
+#define R_SP 13
+_Unwind_VRS_Result _Unwind_VRS_Pop(_Unwind_Context *context,
+_Unwind_VRS_RegClass regclass,
+uint32_t descriminator,
+_Unwind_VRS_DataRepresentation representation)
+{
+phase1_virtual_register_set *vrsp = (phase1_virtual_register_set *)context;
+switch (regclass) {
+case _UVRSC_CORE:
+{
+/* If SP is included in the mask, the loaded value is used in preference to
+* the writeback value, but only on completion of the loading.
+*/
+uint32_t mask, *vsp, *rp, sp_loaded;
+if (representation != _UVRSD_UINT32)
+return _UVRSR_FAILED;
+vsp = (uint32_t *)vrsp->core.r[R_SP];
+rp = (uint32_t *)&vrsp->core;
+mask = descriminator & 0xffff;
+sp_loaded = mask & (1 << R_SP);
+while (mask != 0) {
+if (mask & 1) {
+#ifdef VRS_DIAGNOSTICS
+printf("VRS Pop r%d\n", rp - &vrsp->core.r[0]);
+#endif
+*rp = *vsp++;
+}
+rp++;
+mask >>= 1;
+}
+if (!sp_loaded)
+vrsp->core.r[R_SP] = (uint32_t)vsp;
+return _UVRSR_OK;
+}
+case _UVRSC_VFP:
+{
+uint32_t start = descriminator >> 16;
+uint32_t count = descriminator & 0xffff;
+if (representation != _UVRSD_VFPX || start + count > 16)
+return _UVRSR_FAILED;
+if (vrsp->demand_save_vfp == 1) { /* Demand-save over phase 1 */
+vrsp->demand_save_vfp = 0;
+__ARM_Unwind_VRS_VFPpreserve(&vrsp->vfp);
+}
+/* Now recover from the stack into the real machine registers.
+* Note we assume FSTMX standard format 1.
+* Do this by saving the current VFP registers to a memory area,
+* moving the in-memory values over that area, and
+* restoring from the whole area.
+*/
+{
+struct vfp_s temp_vfp;
+uint64_t *vsp;
+__ARM_Unwind_VRS_VFPpreserve(&temp_vfp);
+vsp = (uint64_t *)vrsp->core.r[R_SP];
+while (count--) {
+#ifdef VRS_DIAGNOSTICS
+printf("VRS Pop D%d = 0x%llx\n", start, *vsp);
+#endif
+temp_vfp.vfp[start++] = *vsp++;
+}
+vrsp->core.r[R_SP] = (uint32_t)((uint32_t *)vsp + 1); /* +1 to skip the format word */
+__ARM_Unwind_VRS_VFPrestore(&temp_vfp);
+}
+return _UVRSR_OK;
+}
+case _UVRSC_FPA:
+{
+uint32_t start = descriminator >> 16;
+uint32_t count = descriminator & 0xffff;
+if (representation != _UVRSD_FPAX || start > 7 || count > 4)
+return _UVRSR_FAILED;
+if (vrsp->demand_save_fpa == 1) { /* Demand-save over phase 1 */
+vrsp->demand_save_fpa = 0;
+__ARM_Unwind_VRS_FPApreserve(&vrsp->fpa);
+}
+/* Now recover from the stack into the real machine registers.
+* Do this by saving the current FPA registers to a memory area,
+* moving the in-memory values over that area, and
+* restoring from the whole area.
+* Unlike VFP, here the range is allowed to wrap round.
+*/
+{
+struct fpa_s temp_fpa;
+struct fpa_reg *vsp;
+__ARM_Unwind_VRS_FPApreserve(&temp_fpa);
+vsp = (struct fpa_reg *)vrsp->core.r[R_SP];
+while (count--) {
+#ifdef VRS_DIAGNOSTICS
+printf("VRS Pop F%d = 0x%-8.8x%-8.8x%-8.8x\n", start, *(uint32_t *)vsp,
+*((uint32_t *)vsp + 1), *((uint32_t *)vsp + 2));
+#endif
+temp_fpa.fpa[start++] = *vsp++;
+start &= 7;
+}
+vrsp->core.r[R_SP] = (uint32_t)vsp;
+__ARM_Unwind_VRS_FPArestore(&temp_fpa);
+}
+return _UVRSR_OK;
+}
+case _UVRSC_WMMXD:
+case _UVRSC_WMMXC:
+return _UVRSR_NOT_IMPLEMENTED;
+default:
+break;
+}
+return _UVRSR_FAILED;
+}
+/* =========================              ========================= */
+/* ========================= The unwinder ========================= */
+/* =========================              ========================= */
+/* This implementation uses the UCB unwinder_cache as follows:
+* reserved1 is documented in the EABI as requiring initialisation to 0.
+*  It is used to manage nested simultaneous propagation. If the value is 0,
+*  the UCB is participating in no propagations. If the value is 1, the UCB
+*  is participating in one propagation. Otherwise the value is a pointer to
+*  a structure holding saved UCB state from the next propagation out.
+*  The structure used is simply a mallocated UCB.
+* reserved2 is used to preserve the call-site address over calls to a
+*  personality routine and cleanup.
+* reserved3 is used to cache the PR address.
+* reserved4 is not used.
+* reserved5 is not used.
+*/
+#define NESTED_CONTEXT      unwinder_cache.reserved1
+#define SAVED_CALLSITE_ADDR unwinder_cache.reserved2
+#define PR_ADDR             unwinder_cache.reserved3
+/* Index table entry: */
+typedef struct __EIT_entry {
+uint32_t fnoffset; /* Relative to base of execution region */
+uint32_t content;
+} __EIT_entry;
+/* Private defines etc: */
+static const uint32_t EXIDX_CANTUNWIND = 1;
+static const uint32_t uint32_highbit = 0x80000000;
+/* ARM C++ personality routines: */
+typedef _Unwind_Reason_Code (*personality_routine)(_Unwind_State,
+_Unwind_Control_Block *,
+_Unwind_Context *);
+WEAKDECL _Unwind_Reason_Code __aeabi_unwind_cpp_pr0(_Unwind_State state, _Unwind_Control_Block *,
+_Unwind_Context *context);
+WEAKDECL _Unwind_Reason_Code __aeabi_unwind_cpp_pr1(_Unwind_State state, _Unwind_Control_Block *,
+_Unwind_Context *context);
+WEAKDECL _Unwind_Reason_Code __aeabi_unwind_cpp_pr2(_Unwind_State state, _Unwind_Control_Block *,
+_Unwind_Context *context);
+/* Various image symbols: */
+struct ExceptionTableInfo {
+uint32_t EIT_base;
+uint32_t EIT_limit;
+};
+/* We define __ARM_ETInfo to allow access to some linker-generated
+names that are not legal C identifiers. __ARM_ETInfo is extern only
+because of scope limitations of the embedded assembler */
+extern const struct ExceptionTableInfo __ARM_ETInfo;
+#define EIT_base \
+((const __EIT_entry *)(__ARM_ETInfo.EIT_base + (const char *)&__ARM_ETInfo))
+#define EIT_limit \
+((const __EIT_entry *)(__ARM_ETInfo.EIT_limit + (const char *)&__ARM_ETInfo))
+/* ----- Address manipulation: ----- */
+/* The following helper function is never called and is present simply
+* for ease of packaging. The constant word within is used by
+* ER_RO_offset_to_addr to compute the RO segment base.
+* The zero word named W is relocated relative to the base B of the
+* segment which includes it, hence B is recoverable at runtime by
+* computing &W - W.
+*/
+extern const uint32_t __ARM_unwind_ROSegBase_SelfOffset;
+__asm void __ARM_unwind_basehelper(void)
+{
+export __ARM_unwind_ROSegBase_SelfOffset;
+R_ARM_ROSEGREL32        EQU 39
+__ARM_unwind_ROSegBase_SelfOffset;
+dcd 0;
+__RELOC R_ARM_ROSEGREL32,__ARM_unwind_ROSegBase_SelfOffset;
+}
+#define ER_RO_SegBase ((uint32_t)&__ARM_unwind_ROSegBase_SelfOffset - \
+__ARM_unwind_ROSegBase_SelfOffset)
+/* And now functions used to convert between segment-relative offsets
+* and absolute addresses.
+*/
+static __inline uint32_t addr_to_ER_RO_offset(uint32_t addr)
+{
+return addr - ER_RO_SegBase;
+}
+static __inline uint32_t ER_RO_offset_to_addr(uint32_t offset)
+{
+extern const uint32_t __ARM_unwind_ROSegBase_SelfOffset;
+return offset + ER_RO_SegBase;
+}
+/* ----- Index table processing ----- */
+/* find_and_expand_eit_entry is a support function used in both phases to set
+* ucb.pr_cache and internal cache.
+* Call with a pointer to the ucb and the return address to look up.
+*
+* The table is contained in the half-open interval
+* [EIT_base, EIT_limit) and is an ordered array of __EIT_entrys.
+* Perform a binary search via C library routine bsearch.
+* The table contains only function start addresses (encoded as offsets), so
+* we need to special-case the end table entry in the comparison function,
+* which we do by assuming the function it describes extends to end of memory.
+* This causes us problems indirectly in that we would like to fault as
+* many attempts as possible to look up an invalid return address. There are
+* several ways an invalid return address can be obtained from a broken
+* program, such as someone corrupting the stack or broken unwind instructions
+* recovered the wrong value. It is plausible that many bad return addresses
+* will be either small integers or will point into the heap or stack, hence
+* it's desirable to get the length of that final function roughly right.
+* Here we make no attempt to do it. Code exclusively for use in toolchains
+* which define a suitable limit symbol could make use of that symbol.
+* Alternatively (QoI) a smart linker could augment the index table with a
+* dummy EXIDX_CANTUNWIND entry pointing just past the last real function.
+*/
+static int EIT_comparator(const void *ck, const void *ce)
+{
+uint32_t return_address_offset = *(const uint32_t *)ck;
+const __EIT_entry *eitp = (const __EIT_entry *)ce;
+const __EIT_entry *next_eitp = eitp + 1;
+uint32_t next_fn;
+if (next_eitp != EIT_limit)
+next_fn = next_eitp->fnoffset;
+else
+next_fn = addr_to_ER_RO_offset(0); /* address 0 is 'just past' the end of memory */
+if (return_address_offset < eitp->fnoffset) return -1;
+if (return_address_offset >= next_fn) return 1;
+return 0;
+}
+static _Unwind_Reason_Code find_and_expand_eit_entry(_Unwind_Control_Block *ucbp,
+uint32_t return_address)
+{
+/* Search the index table for an entry containing the specified return
+* address. The EIT contains function offsets relative to the base of the
+* execute region so adjust the return address accordingly.
+*/
+uint32_t return_address_offset = addr_to_ER_RO_offset(return_address);
+const __EIT_entry *base = EIT_base;
+size_t nelems = EIT_limit - EIT_base;
+const __EIT_entry *eitp =
+(const __EIT_entry *) bsearch(&return_address_offset, base, nelems,
+sizeof(__EIT_entry), EIT_comparator);
+if (eitp == NULL) {
+/* The return address we have was not found in the EIT.
+* This breaks the scan and we have to indicate failure.
+*/
+ucbp->PR_ADDR = NULL;
+DEBUGGER_BOTTLENECK(ucbp, _UASUBSYS_UNWINDER, _UAACT_ENDING, _UAARG_ENDING_UNWINDER_LOOKUPFAILED);
+return _URC_FAILURE;
+}
+/* Cache the function offset */
+ucbp->pr_cache.fnstart = ER_RO_offset_to_addr(eitp->fnoffset);
+/* Can this frame be unwound at all? */
+if (eitp->content == EXIDX_CANTUNWIND) {
+ucbp->PR_ADDR = NULL;
+DEBUGGER_BOTTLENECK(ucbp, _UASUBSYS_UNWINDER, _UAACT_ENDING, _UAARG_ENDING_NOUNWIND);
+return _URC_FAILURE;
+}
+/* Obtain the address of the "real" __EHT_Header word */
+if (eitp->content & uint32_highbit) {
+/* It is immediate data */
+ucbp->pr_cache.ehtp = (_Unwind_EHT_Header *)&eitp->content;
+ucbp->pr_cache.additional = 1;
+} else {
+/* The content field is a segment relative offset to an _Unwind_EHT_Entry structure */
+ucbp->pr_cache.ehtp = (_Unwind_EHT_Header *)ER_RO_offset_to_addr(eitp->content);
+ucbp->pr_cache.additional = 0;
+}
+/* Discover the personality routine address */
+if (*(uint32_t *)(ucbp->pr_cache.ehtp) & uint32_highbit) {
+/* It is immediate data - compute matching pr */
+uint32_t idx = ((*(uint32_t *)(ucbp->pr_cache.ehtp)) >> 24) & 0xf;
+if (idx == 0) ucbp->PR_ADDR = (uint32_t)&__aeabi_unwind_cpp_pr0;
+else if (idx == 1) ucbp->PR_ADDR = (uint32_t)&__aeabi_unwind_cpp_pr1;
+else if (idx == 2) ucbp->PR_ADDR = (uint32_t)&__aeabi_unwind_cpp_pr2;
+else { /* Failed */
+ucbp->PR_ADDR = NULL;
+DEBUGGER_BOTTLENECK(ucbp, _UASUBSYS_UNWINDER, _UAACT_ENDING, _UAARG_ENDING_TABLECORRUPT);
+return _URC_FAILURE;
+}
+} else {
+/* Execute region offset to PR */
+ucbp->PR_ADDR = ER_RO_offset_to_addr(*(uint32_t *)(ucbp->pr_cache.ehtp));
+}
+return _URC_OK;
+}
+/* ----- Unwinding: ----- */
+/* Fwd decl */
+static NORETURNDECL void unwind_next_frame(_Unwind_Control_Block *ucbp, phase2_virtual_register_set *vrsp);
+/* Helper fn: If the demand_save flag in a phase1_virtual_register_set was
+* zeroed, the registers were demand-saved. This function restores from
+* the save area.
+*/
+static void restore_non_core_regs(phase1_virtual_register_set *vrsp)
+{
+if (vrsp->demand_save_vfp == 0)
+__ARM_Unwind_VRS_VFPrestore(&vrsp->vfp);
+if (vrsp->demand_save_fpa == 0)
+__ARM_Unwind_VRS_FPArestore(&vrsp->fpa);
+}
+/* _Unwind_RaiseException is the external entry point to begin unwinding */
+__asm _Unwind_Reason_Code _Unwind_RaiseException(_Unwind_Control_Block *ucbp)
+{
+extern __ARM_Unwind_RaiseException;
+MAYBE_SWITCH_TO_ARM_STATE;
+/* Create a phase2_virtual_register_set on the stack */
+/* Save the core registers, carefully writing the original sp value */
+stmfd sp!,{r13-r15};  /* pushed 3 words => 3 words */
+stmfd sp!,{r0-r12};   /* pushed 13 words => 16 words */
+/* Write zeroes for the demand_save bytes so no saving occurs in phase 2 */
+mov r1,#0;
+str r1,[sp,#-4]!;     /* pushed 1 word => 17 words */
+mov r1,sp;
+sub sp,sp,#4;         /* preserve 8 byte alignment => 18 words */
+/* Now pass to C (with r0 still valid) to do the real work.
+* r0 = ucbp, r1 = phase2_virtual_register_set.
+* If we get control back, pop the stack and return preserving r0.
+*/
+#if OLD_STYLE_INTERWORKING
+ldr r2,Unwind_RaiseException_Offset;
+add r2,r2,pc;
+mov lr,pc;
+Offset_Base
+bx r2;
+#else
+/* on arch 5T and later the linker will fix 'bl' => 'blx' as
+needed */
+bl  __ARM_Unwind_RaiseException;
+#endif
+ldr r14,[sp,#16*4];
+add sp,sp,#18*4;
+RET_LR;
+#if OLD_STYLE_INTERWORKING
+Unwind_RaiseException_Offset dcd __ARM_Unwind_RaiseException - Offset_Base;
+#endif
+MAYBE_CODE16;
+/* Alternate symbol names for difficult symbols.
+* It is possible no functions included in the image require
+* a handler table. Therefore make only a weak reference to
+* the handler table base symbol, which may be absent.
+*/
+extern |.ARM.exidx$$Base|;
+extern |.ARM.exidx$$Limit|;
+extern |.ARM.extab$$Base| WEAKASMDECL;
+export __ARM_ETInfo;
+/* these are offsets for /ropi */
+__ARM_ETInfo /* layout must match struct ExceptionTableInfo */
+eit_base   dcd |.ARM.exidx$$Base|  - __ARM_ETInfo; /* index table base */
+eit_limit  dcd |.ARM.exidx$$Limit| - __ARM_ETInfo; /* index table limit */
+}
+/* __ARM_Unwind_RaiseException performs phase 1 unwinding */
+_Unwind_Reason_Code __ARM_Unwind_RaiseException(_Unwind_Control_Block *ucbp,
+phase2_virtual_register_set *entry_VRSp)
+{
+phase1_virtual_register_set phase1_VRS;
+/* Is this a nested simultaneous propagation?
+* (see comments with _Unwind_Complete)
+*/
+if (ucbp->NESTED_CONTEXT == 0) {
+/* No - this is only propagation */
+ucbp->NESTED_CONTEXT = 1;
+} else {
+/* Yes - cache the state elsewhere and restore it when the propagation ends */
+/* This representation wastes space and uses malloc; do better?
+* On the other hand will it ever be used in practice?
+*/
+_Unwind_Control_Block *saved_ucbp =
+(_Unwind_Control_Block *)malloc(sizeof(_Unwind_Control_Block));
+if (ucbp == NULL) {
+DEBUGGER_BOTTLENECK(ucbp, _UASUBSYS_UNWINDER, _UAACT_ENDING, _UAARG_ENDING_UNWINDER_BUFFERFAILED);
+return _URC_FAILURE;
+}
+saved_ucbp->unwinder_cache = ucbp->unwinder_cache;
+saved_ucbp->barrier_cache = ucbp->barrier_cache;
+saved_ucbp->cleanup_cache = ucbp->cleanup_cache;
+ucbp->NESTED_CONTEXT = (uint32_t)saved_ucbp;
+}
+/* entry_VRSp contains the core registers as they were when
+* _Unwind_RaiseException was called.  Copy the call-site address to r15
+* then copy all the registers to phase1_VRS for the phase 1 stack scan.
+*/
+entry_VRSp->core.r[15] = entry_VRSp->core.r[14];
+phase1_VRS.core = entry_VRSp->core;
+/* For phase 1 only ensure non-core registers are saved before use.
+* If WMMX registers are supported, initialise their flags here and
+* take appropriate action elsewhere.
+*/
+phase1_VRS.demand_save_vfp = 1;
+phase1_VRS.demand_save_fpa = 1;
+/* Now perform a virtual unwind until a propagation barrier is met, or
+* until something goes wrong.  If something does go wrong, we ought (I
+* suppose) to restore registers we may have destroyed.
+*/
+while (1) {
+_Unwind_Reason_Code pr_result;
+/* Search the index table for the required entry.  Cache the index table
+* pointer, and obtain and cache the addresses of the "real" __EHT_Header
+* word and the personality routine.
+*/
+if (find_and_expand_eit_entry(ucbp, phase1_VRS.core.r[15]) != _URC_OK) {
+restore_non_core_regs(&phase1_VRS);
+/* Debugger bottleneck fn called during lookup */
+return _URC_FAILURE;
+}
+/* Call the pr to decide what to do */
+pr_result = ((personality_routine)ucbp->PR_ADDR)(_US_VIRTUAL_UNWIND_FRAME,
+ucbp,
+(_Unwind_Context *)&phase1_VRS);
+if (pr_result == _URC_HANDLER_FOUND) break;
+if (pr_result == _URC_CONTINUE_UNWIND) continue;
+/* If we get here some sort of failure has occurred in the
+* pr and probably the pr returned _URC_FAILURE
+*/
+restore_non_core_regs(&phase1_VRS);
+return _URC_FAILURE;
+}
+/* Propagation barrier located... restore entry register state of non-core regs */
+restore_non_core_regs(&phase1_VRS);
+/* Initiate real unwinding */
+unwind_next_frame(ucbp, entry_VRSp);
+/* Unreached, but keep compiler quiet: */
+return _URC_FAILURE;
+}
+/* unwind_next_frame performs phase 2 unwinding */
+static NORETURNDECL void unwind_next_frame(_Unwind_Control_Block *ucbp, phase2_virtual_register_set *vrsp)
+{
+while (1) {
+_Unwind_Reason_Code pr_result;
+/* Search the index table for the required entry.  Cache the index table
+* pointer, and obtain and cache the addresses of the "real" __EHT_Header
+* word and the personality routine.
+*/
+if (find_and_expand_eit_entry(ucbp, vrsp->core.r[15]) != _URC_OK)
+abort();
+/* Save the call-site address and call the pr to do whatever it
+* wants to do on this new frame.
+*/
+ucbp->SAVED_CALLSITE_ADDR = vrsp->core.r[15];
+pr_result = ((personality_routine)ucbp->PR_ADDR)(_US_UNWIND_FRAME_STARTING, ucbp,
+(_Unwind_Context *)vrsp);
+if (pr_result == _URC_INSTALL_CONTEXT) {
+/* Upload the registers */
+__ARM_Unwind_VRS_corerestore(&vrsp->core);
+} else if (pr_result == _URC_CONTINUE_UNWIND)
+continue;
+else
+abort();
+}
+}
+/* _Unwind_Resume is the external entry point called after a cleanup
+* to resume unwinding. It tail-calls a helper function,
+* __ARM_Unwind_Resume, which never returns.
+*/
+__asm NORETURNDECL void _Unwind_Resume(_Unwind_Control_Block *ucbp)
+{
+extern __ARM_Unwind_Resume;
+MAYBE_SWITCH_TO_ARM_STATE;
+/* Create a phase2_virtual_register_set on the stack */
+/* Save the core registers, carefully writing the original sp value */
+stmfd sp!,{r13-r15};  /* pushed 3 words => 3 words */
+stmfd sp!,{r0-r12};   /* pushed 13 words => 16 words */
+/* Write zeroes for the demand_save bytes so no saving occurs in phase 2 */
+mov r1,#0;
+str r1,[sp,#-4]!;     /* pushed 1 word => 17 words */
+mov r1,sp;
+sub sp,sp,#4;         /* preserve 8 byte alignment => 18 words */
+/* Now pass to C (with r0 still valid) to do the real work.
+* r0 = ucbp, r1 = phase2_virtual_register_set.
+* This call never returns.
+*/
+#ifdef __APCS_INTERWORK
+ldr r2,Unwind_Resume_Offset;
+add r2,r2,pc;
+bx r2;
+Unwind_Resume_Offset dcd __ARM_Unwind_Resume - .;
+#else
+b __ARM_Unwind_Resume;
+#endif
+MAYBE_CODE16;
+}
+/* Helper function for _Unwind_Resume */
+NORETURNDECL void __ARM_Unwind_Resume(_Unwind_Control_Block *ucbp,
+phase2_virtual_register_set *entry_VRSp)
+{
+_Unwind_Reason_Code pr_result;
+/* Recover saved state */
+entry_VRSp->core.r[15] = ucbp->SAVED_CALLSITE_ADDR;
+/* Call the cached PR and dispatch */
+pr_result = ((personality_routine)ucbp->PR_ADDR)(_US_UNWIND_FRAME_RESUME, ucbp,
+(_Unwind_Context *)entry_VRSp);
+if (pr_result == _URC_INSTALL_CONTEXT) {
+/* Upload the registers */
+__ARM_Unwind_VRS_corerestore(&entry_VRSp->core);
+} else if (pr_result == _URC_CONTINUE_UNWIND)
+unwind_next_frame(ucbp, entry_VRSp);
+else
+abort();
+}
+/* _Unwind_Complete is called at the end of a propagation.
+* If we support multiple simultaneous propagations, restore the cached state
+* of the previous propagation here.
+*/
+void _Unwind_Complete(_Unwind_Control_Block *ucbp)
+{
+_Unwind_Control_Block *context = (_Unwind_Control_Block *)ucbp->NESTED_CONTEXT;
+if ((uint32_t)context == 0) abort();  /* should be impossible */
+if ((uint32_t)context == 1) {
+/* This was the only ongoing propagation of this object */
+ucbp->NESTED_CONTEXT--;
+return;
+}
+/* Otherwise we copy the state back from the cache structure pointed to
+* by ucbp->NESTED_CONTEXT.
+*/
+/* This first one updates ucbp->NESTED_CONTEXT */
+ucbp->unwinder_cache = context->unwinder_cache;
+ucbp->barrier_cache = context->barrier_cache;
+ucbp->cleanup_cache = context->cleanup_cache;
+free(context);
+}
+#endif /* unwinder_c */
+#ifdef unwind_activity_c
+/* Runtime debug "bottleneck function": */
+/* (not in the current Exceptions EABI document) */
+void _Unwind_Activity(_Unwind_Control_Block *ucbp, uint32_t reason, uint32_t arg)
+{
+#ifdef UNWIND_ACTIVITY_DIAGNOSTICS
+uint32_t who = reason >> 24;
+uint32_t activity = reason & 0xffffff;
+printf("_Unwind_Activity: UCB=0x%8.8x Reason=(", (uint32_t)ucbp);
+switch (who) {
+case _UASUBSYS_UNWINDER:
+printf("unw,");
+if (activity >= 0x80)
+printf("%x) Arg=0x%8.8x\n", activity, arg);
+break;
+case _UASUBSYS_CPP:
+printf("C++,");
+if (activity >= 0x80) {
+if (activity == _UAACT_CPP_TYPEINFO)
+printf("typeinfo) Typeinfo=0x%8.8x\n", arg);
+else
+printf("%x) Arg=0x%8.8x\n", activity, arg);
+}
+break;
+default:
+printf("???,");
+if (activity >= 0x80)
+printf("%x) Arg=0x%8.8x\n", activity, arg);
+break;
+}
+if (activity < 0x80) {
+switch (activity) {
+case _UAACT_STARTING:
+printf("starting) Typeinfo=0x%8.8x\n", arg);
+break;
+case _UAACT_ENDING:
+printf("ending) Cause=%d\n", arg);
+break;
+case _UAACT_BARRIERFOUND:
+printf("barrierfound) Pad=0x%8.8x\n", arg);
+break;
+case _UAACT_PADENTRY:
+printf("padentry) Pad=0x%8.8x\n", arg);
+break;
+default:
+printf("%x) Arg=0x%8.8x\n", activity, arg);
+break;
+}
+}
+#endif
+}
+#endif /* unwind_activity_c */