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unwind.c
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/*
* Copyright (C) 1999-2004 Hewlett-Packard Co
* David Mosberger-Tang <[email protected]>
* Copyright (C) 2003 Fenghua Yu <[email protected]>
* - Change pt_regs_off() to make it less dependent on pt_regs structure.
*/
/*
* This file implements call frame unwind support for the Linux
* kernel. Parsing and processing the unwind information is
* time-consuming, so this implementation translates the unwind
* descriptors into unwind scripts. These scripts are very simple
* (basically a sequence of assignments) and efficient to execute.
* They are cached for later re-use. Each script is specific for a
* given instruction pointer address and the set of predicate values
* that the script depends on (most unwind descriptors are
* unconditional and scripts often do not depend on predicates at
* all). This code is based on the unwind conventions described in
* the "IA-64 Software Conventions and Runtime Architecture" manual.
*
* SMP conventions:
* o updates to the global unwind data (in structure "unw") are serialized
* by the unw.lock spinlock
* o each unwind script has its own read-write lock; a thread must acquire
* a read lock before executing a script and must acquire a write lock
* before modifying a script
* o if both the unw.lock spinlock and a script's read-write lock must be
* acquired, then the read-write lock must be acquired first.
*/
#include <linux/module.h>
#include <linux/bootmem.h>
#include <linux/elf.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <asm/unwind.h>
#include <asm/delay.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/ptrace_offsets.h>
#include <asm/rse.h>
#include <asm/sections.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include "entry.h"
#include "unwind_i.h"
#define UNW_LOG_CACHE_SIZE 7 /* each unw_script is ~256 bytes in size */
#define UNW_CACHE_SIZE (1 << UNW_LOG_CACHE_SIZE)
#define UNW_LOG_HASH_SIZE (UNW_LOG_CACHE_SIZE + 1)
#define UNW_HASH_SIZE (1 << UNW_LOG_HASH_SIZE)
#define UNW_STATS 0 /* WARNING: this disabled interrupts for long time-spans!! */
#ifdef UNW_DEBUG
static unsigned int unw_debug_level = UNW_DEBUG;
# define UNW_DEBUG_ON(n) unw_debug_level >= n
/* Do not code a printk level, not all debug lines end in newline */
# define UNW_DPRINT(n, ...) if (UNW_DEBUG_ON(n)) printk(__VA_ARGS__)
# undef inline
# define inline
#else /* !UNW_DEBUG */
# define UNW_DEBUG_ON(n) 0
# define UNW_DPRINT(n, ...)
#endif /* UNW_DEBUG */
#if UNW_STATS
# define STAT(x...) x
#else
# define STAT(x...)
#endif
#define alloc_reg_state() kmalloc(sizeof(struct unw_reg_state), GFP_ATOMIC)
#define free_reg_state(usr) kfree(usr)
#define alloc_labeled_state() kmalloc(sizeof(struct unw_labeled_state), GFP_ATOMIC)
#define free_labeled_state(usr) kfree(usr)
typedef unsigned long unw_word;
typedef unsigned char unw_hash_index_t;
static struct {
spinlock_t lock; /* spinlock for unwind data */
/* list of unwind tables (one per load-module) */
struct unw_table *tables;
unsigned long r0; /* constant 0 for r0 */
/* table of registers that prologues can save (and order in which they're saved): */
const unsigned char save_order[8];
/* maps a preserved register index (preg_index) to corresponding switch_stack offset: */
unsigned short sw_off[sizeof(struct unw_frame_info) / 8];
unsigned short lru_head; /* index of lead-recently used script */
unsigned short lru_tail; /* index of most-recently used script */
/* index into unw_frame_info for preserved register i */
unsigned short preg_index[UNW_NUM_REGS];
short pt_regs_offsets[32];
/* unwind table for the kernel: */
struct unw_table kernel_table;
/* unwind table describing the gate page (kernel code that is mapped into user space): */
size_t gate_table_size;
unsigned long *gate_table;
/* hash table that maps instruction pointer to script index: */
unsigned short hash[UNW_HASH_SIZE];
/* script cache: */
struct unw_script cache[UNW_CACHE_SIZE];
# ifdef UNW_DEBUG
const char *preg_name[UNW_NUM_REGS];
# endif
# if UNW_STATS
struct {
struct {
int lookups;
int hinted_hits;
int normal_hits;
int collision_chain_traversals;
} cache;
struct {
unsigned long build_time;
unsigned long run_time;
unsigned long parse_time;
int builds;
int news;
int collisions;
int runs;
} script;
struct {
unsigned long init_time;
unsigned long unwind_time;
int inits;
int unwinds;
} api;
} stat;
# endif
} unw = {
.tables = &unw.kernel_table,
.lock = __SPIN_LOCK_UNLOCKED(unw.lock),
.save_order = {
UNW_REG_RP, UNW_REG_PFS, UNW_REG_PSP, UNW_REG_PR,
UNW_REG_UNAT, UNW_REG_LC, UNW_REG_FPSR, UNW_REG_PRI_UNAT_GR
},
.preg_index = {
offsetof(struct unw_frame_info, pri_unat_loc)/8, /* PRI_UNAT_GR */
offsetof(struct unw_frame_info, pri_unat_loc)/8, /* PRI_UNAT_MEM */
offsetof(struct unw_frame_info, bsp_loc)/8,
offsetof(struct unw_frame_info, bspstore_loc)/8,
offsetof(struct unw_frame_info, pfs_loc)/8,
offsetof(struct unw_frame_info, rnat_loc)/8,
offsetof(struct unw_frame_info, psp)/8,
offsetof(struct unw_frame_info, rp_loc)/8,
offsetof(struct unw_frame_info, r4)/8,
offsetof(struct unw_frame_info, r5)/8,
offsetof(struct unw_frame_info, r6)/8,
offsetof(struct unw_frame_info, r7)/8,
offsetof(struct unw_frame_info, unat_loc)/8,
offsetof(struct unw_frame_info, pr_loc)/8,
offsetof(struct unw_frame_info, lc_loc)/8,
offsetof(struct unw_frame_info, fpsr_loc)/8,
offsetof(struct unw_frame_info, b1_loc)/8,
offsetof(struct unw_frame_info, b2_loc)/8,
offsetof(struct unw_frame_info, b3_loc)/8,
offsetof(struct unw_frame_info, b4_loc)/8,
offsetof(struct unw_frame_info, b5_loc)/8,
offsetof(struct unw_frame_info, f2_loc)/8,
offsetof(struct unw_frame_info, f3_loc)/8,
offsetof(struct unw_frame_info, f4_loc)/8,
offsetof(struct unw_frame_info, f5_loc)/8,
offsetof(struct unw_frame_info, fr_loc[16 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[17 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[18 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[19 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[20 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[21 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[22 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[23 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[24 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[25 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[26 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[27 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[28 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[29 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[30 - 16])/8,
offsetof(struct unw_frame_info, fr_loc[31 - 16])/8,
},
.pt_regs_offsets = {
[0] = -1,
offsetof(struct pt_regs, r1),
offsetof(struct pt_regs, r2),
offsetof(struct pt_regs, r3),
[4] = -1, [5] = -1, [6] = -1, [7] = -1,
offsetof(struct pt_regs, r8),
offsetof(struct pt_regs, r9),
offsetof(struct pt_regs, r10),
offsetof(struct pt_regs, r11),
offsetof(struct pt_regs, r12),
offsetof(struct pt_regs, r13),
offsetof(struct pt_regs, r14),
offsetof(struct pt_regs, r15),
offsetof(struct pt_regs, r16),
offsetof(struct pt_regs, r17),
offsetof(struct pt_regs, r18),
offsetof(struct pt_regs, r19),
offsetof(struct pt_regs, r20),
offsetof(struct pt_regs, r21),
offsetof(struct pt_regs, r22),
offsetof(struct pt_regs, r23),
offsetof(struct pt_regs, r24),
offsetof(struct pt_regs, r25),
offsetof(struct pt_regs, r26),
offsetof(struct pt_regs, r27),
offsetof(struct pt_regs, r28),
offsetof(struct pt_regs, r29),
offsetof(struct pt_regs, r30),
offsetof(struct pt_regs, r31),
},
.hash = { [0 ... UNW_HASH_SIZE - 1] = -1 },
#ifdef UNW_DEBUG
.preg_name = {
"pri_unat_gr", "pri_unat_mem", "bsp", "bspstore", "ar.pfs", "ar.rnat", "psp", "rp",
"r4", "r5", "r6", "r7",
"ar.unat", "pr", "ar.lc", "ar.fpsr",
"b1", "b2", "b3", "b4", "b5",
"f2", "f3", "f4", "f5",
"f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23",
"f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31"
}
#endif
};
static inline int
read_only (void *addr)
{
return (unsigned long) ((char *) addr - (char *) &unw.r0) < sizeof(unw.r0);
}
/*
* Returns offset of rREG in struct pt_regs.
*/
static inline unsigned long
pt_regs_off (unsigned long reg)
{
short off = -1;
if (reg < ARRAY_SIZE(unw.pt_regs_offsets))
off = unw.pt_regs_offsets[reg];
if (off < 0) {
UNW_DPRINT(0, "unwind.%s: bad scratch reg r%lu\n", __func__, reg);
off = 0;
}
return (unsigned long) off;
}
static inline struct pt_regs *
get_scratch_regs (struct unw_frame_info *info)
{
if (!info->pt) {
/* This should not happen with valid unwind info. */
UNW_DPRINT(0, "unwind.%s: bad unwind info: resetting info->pt\n", __func__);
if (info->flags & UNW_FLAG_INTERRUPT_FRAME)
info->pt = (unsigned long) ((struct pt_regs *) info->psp - 1);
else
info->pt = info->sp - 16;
}
UNW_DPRINT(3, "unwind.%s: sp 0x%lx pt 0x%lx\n", __func__, info->sp, info->pt);
return (struct pt_regs *) info->pt;
}
/* Unwind accessors. */
int
unw_access_gr (struct unw_frame_info *info, int regnum, unsigned long *val, char *nat, int write)
{
unsigned long *addr, *nat_addr, nat_mask = 0, dummy_nat;
struct unw_ireg *ireg;
struct pt_regs *pt;
if ((unsigned) regnum - 1 >= 127) {
if (regnum == 0 && !write) {
*val = 0; /* read r0 always returns 0 */
*nat = 0;
return 0;
}
UNW_DPRINT(0, "unwind.%s: trying to access non-existent r%u\n",
__func__, regnum);
return -1;
}
if (regnum < 32) {
if (regnum >= 4 && regnum <= 7) {
/* access a preserved register */
ireg = &info->r4 + (regnum - 4);
addr = ireg->loc;
if (addr) {
nat_addr = addr + ireg->nat.off;
switch (ireg->nat.type) {
case UNW_NAT_VAL:
/* simulate getf.sig/setf.sig */
if (write) {
if (*nat) {
/* write NaTVal and be done with it */
addr[0] = 0;
addr[1] = 0x1fffe;
return 0;
}
addr[1] = 0x1003e;
} else {
if (addr[0] == 0 && addr[1] == 0x1ffe) {
/* return NaT and be done with it */
*val = 0;
*nat = 1;
return 0;
}
}
/* fall through */
case UNW_NAT_NONE:
dummy_nat = 0;
nat_addr = &dummy_nat;
break;
case UNW_NAT_MEMSTK:
nat_mask = (1UL << ((long) addr & 0x1f8)/8);
break;
case UNW_NAT_REGSTK:
nat_addr = ia64_rse_rnat_addr(addr);
if ((unsigned long) addr < info->regstk.limit
|| (unsigned long) addr >= info->regstk.top)
{
UNW_DPRINT(0, "unwind.%s: %p outside of regstk "
"[0x%lx-0x%lx)\n",
__func__, (void *) addr,
info->regstk.limit,
info->regstk.top);
return -1;
}
if ((unsigned long) nat_addr >= info->regstk.top)
nat_addr = &info->sw->ar_rnat;
nat_mask = (1UL << ia64_rse_slot_num(addr));
break;
}
} else {
addr = &info->sw->r4 + (regnum - 4);
nat_addr = &info->sw->ar_unat;
nat_mask = (1UL << ((long) addr & 0x1f8)/8);
}
} else {
/* access a scratch register */
pt = get_scratch_regs(info);
addr = (unsigned long *) ((unsigned long)pt + pt_regs_off(regnum));
if (info->pri_unat_loc)
nat_addr = info->pri_unat_loc;
else
nat_addr = &info->sw->caller_unat;
nat_mask = (1UL << ((long) addr & 0x1f8)/8);
}
} else {
/* access a stacked register */
addr = ia64_rse_skip_regs((unsigned long *) info->bsp, regnum - 32);
nat_addr = ia64_rse_rnat_addr(addr);
if ((unsigned long) addr < info->regstk.limit
|| (unsigned long) addr >= info->regstk.top)
{
UNW_DPRINT(0, "unwind.%s: ignoring attempt to access register outside "
"of rbs\n", __func__);
return -1;
}
if ((unsigned long) nat_addr >= info->regstk.top)
nat_addr = &info->sw->ar_rnat;
nat_mask = (1UL << ia64_rse_slot_num(addr));
}
if (write) {
if (read_only(addr)) {
UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n",
__func__);
} else {
*addr = *val;
if (*nat)
*nat_addr |= nat_mask;
else
*nat_addr &= ~nat_mask;
}
} else {
if ((*nat_addr & nat_mask) == 0) {
*val = *addr;
*nat = 0;
} else {
*val = 0; /* if register is a NaT, *addr may contain kernel data! */
*nat = 1;
}
}
return 0;
}
EXPORT_SYMBOL(unw_access_gr);
int
unw_access_br (struct unw_frame_info *info, int regnum, unsigned long *val, int write)
{
unsigned long *addr;
struct pt_regs *pt;
switch (regnum) {
/* scratch: */
case 0: pt = get_scratch_regs(info); addr = &pt->b0; break;
case 6: pt = get_scratch_regs(info); addr = &pt->b6; break;
case 7: pt = get_scratch_regs(info); addr = &pt->b7; break;
/* preserved: */
case 1: case 2: case 3: case 4: case 5:
addr = *(&info->b1_loc + (regnum - 1));
if (!addr)
addr = &info->sw->b1 + (regnum - 1);
break;
default:
UNW_DPRINT(0, "unwind.%s: trying to access non-existent b%u\n",
__func__, regnum);
return -1;
}
if (write)
if (read_only(addr)) {
UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n",
__func__);
} else
*addr = *val;
else
*val = *addr;
return 0;
}
EXPORT_SYMBOL(unw_access_br);
int
unw_access_fr (struct unw_frame_info *info, int regnum, struct ia64_fpreg *val, int write)
{
struct ia64_fpreg *addr = NULL;
struct pt_regs *pt;
if ((unsigned) (regnum - 2) >= 126) {
UNW_DPRINT(0, "unwind.%s: trying to access non-existent f%u\n",
__func__, regnum);
return -1;
}
if (regnum <= 5) {
addr = *(&info->f2_loc + (regnum - 2));
if (!addr)
addr = &info->sw->f2 + (regnum - 2);
} else if (regnum <= 15) {
if (regnum <= 11) {
pt = get_scratch_regs(info);
addr = &pt->f6 + (regnum - 6);
}
else
addr = &info->sw->f12 + (regnum - 12);
} else if (regnum <= 31) {
addr = info->fr_loc[regnum - 16];
if (!addr)
addr = &info->sw->f16 + (regnum - 16);
} else {
struct task_struct *t = info->task;
if (write)
ia64_sync_fph(t);
else
ia64_flush_fph(t);
addr = t->thread.fph + (regnum - 32);
}
if (write)
if (read_only(addr)) {
UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n",
__func__);
} else
*addr = *val;
else
*val = *addr;
return 0;
}
EXPORT_SYMBOL(unw_access_fr);
int
unw_access_ar (struct unw_frame_info *info, int regnum, unsigned long *val, int write)
{
unsigned long *addr;
struct pt_regs *pt;
switch (regnum) {
case UNW_AR_BSP:
addr = info->bsp_loc;
if (!addr)
addr = &info->sw->ar_bspstore;
break;
case UNW_AR_BSPSTORE:
addr = info->bspstore_loc;
if (!addr)
addr = &info->sw->ar_bspstore;
break;
case UNW_AR_PFS:
addr = info->pfs_loc;
if (!addr)
addr = &info->sw->ar_pfs;
break;
case UNW_AR_RNAT:
addr = info->rnat_loc;
if (!addr)
addr = &info->sw->ar_rnat;
break;
case UNW_AR_UNAT:
addr = info->unat_loc;
if (!addr)
addr = &info->sw->caller_unat;
break;
case UNW_AR_LC:
addr = info->lc_loc;
if (!addr)
addr = &info->sw->ar_lc;
break;
case UNW_AR_EC:
if (!info->cfm_loc)
return -1;
if (write)
*info->cfm_loc =
(*info->cfm_loc & ~(0x3fUL << 52)) | ((*val & 0x3f) << 52);
else
*val = (*info->cfm_loc >> 52) & 0x3f;
return 0;
case UNW_AR_FPSR:
addr = info->fpsr_loc;
if (!addr)
addr = &info->sw->ar_fpsr;
break;
case UNW_AR_RSC:
pt = get_scratch_regs(info);
addr = &pt->ar_rsc;
break;
case UNW_AR_CCV:
pt = get_scratch_regs(info);
addr = &pt->ar_ccv;
break;
case UNW_AR_CSD:
pt = get_scratch_regs(info);
addr = &pt->ar_csd;
break;
case UNW_AR_SSD:
pt = get_scratch_regs(info);
addr = &pt->ar_ssd;
break;
default:
UNW_DPRINT(0, "unwind.%s: trying to access non-existent ar%u\n",
__func__, regnum);
return -1;
}
if (write) {
if (read_only(addr)) {
UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n",
__func__);
} else
*addr = *val;
} else
*val = *addr;
return 0;
}
EXPORT_SYMBOL(unw_access_ar);
int
unw_access_pr (struct unw_frame_info *info, unsigned long *val, int write)
{
unsigned long *addr;
addr = info->pr_loc;
if (!addr)
addr = &info->sw->pr;
if (write) {
if (read_only(addr)) {
UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n",
__func__);
} else
*addr = *val;
} else
*val = *addr;
return 0;
}
EXPORT_SYMBOL(unw_access_pr);
/* Routines to manipulate the state stack. */
static inline void
push (struct unw_state_record *sr)
{
struct unw_reg_state *rs;
rs = alloc_reg_state();
if (!rs) {
printk(KERN_ERR "unwind: cannot stack reg state!\n");
return;
}
memcpy(rs, &sr->curr, sizeof(*rs));
sr->curr.next = rs;
}
static void
pop (struct unw_state_record *sr)
{
struct unw_reg_state *rs = sr->curr.next;
if (!rs) {
printk(KERN_ERR "unwind: stack underflow!\n");
return;
}
memcpy(&sr->curr, rs, sizeof(*rs));
free_reg_state(rs);
}
/* Make a copy of the state stack. Non-recursive to avoid stack overflows. */
static struct unw_reg_state *
dup_state_stack (struct unw_reg_state *rs)
{
struct unw_reg_state *copy, *prev = NULL, *first = NULL;
while (rs) {
copy = alloc_reg_state();
if (!copy) {
printk(KERN_ERR "unwind.dup_state_stack: out of memory\n");
return NULL;
}
memcpy(copy, rs, sizeof(*copy));
if (first)
prev->next = copy;
else
first = copy;
rs = rs->next;
prev = copy;
}
return first;
}
/* Free all stacked register states (but not RS itself). */
static void
free_state_stack (struct unw_reg_state *rs)
{
struct unw_reg_state *p, *next;
for (p = rs->next; p != NULL; p = next) {
next = p->next;
free_reg_state(p);
}
rs->next = NULL;
}
/* Unwind decoder routines */
static enum unw_register_index __attribute_const__
decode_abreg (unsigned char abreg, int memory)
{
switch (abreg) {
case 0x04 ... 0x07: return UNW_REG_R4 + (abreg - 0x04);
case 0x22 ... 0x25: return UNW_REG_F2 + (abreg - 0x22);
case 0x30 ... 0x3f: return UNW_REG_F16 + (abreg - 0x30);
case 0x41 ... 0x45: return UNW_REG_B1 + (abreg - 0x41);
case 0x60: return UNW_REG_PR;
case 0x61: return UNW_REG_PSP;
case 0x62: return memory ? UNW_REG_PRI_UNAT_MEM : UNW_REG_PRI_UNAT_GR;
case 0x63: return UNW_REG_RP;
case 0x64: return UNW_REG_BSP;
case 0x65: return UNW_REG_BSPSTORE;
case 0x66: return UNW_REG_RNAT;
case 0x67: return UNW_REG_UNAT;
case 0x68: return UNW_REG_FPSR;
case 0x69: return UNW_REG_PFS;
case 0x6a: return UNW_REG_LC;
default:
break;
}
UNW_DPRINT(0, "unwind.%s: bad abreg=0x%x\n", __func__, abreg);
return UNW_REG_LC;
}
static void
set_reg (struct unw_reg_info *reg, enum unw_where where, int when, unsigned long val)
{
reg->val = val;
reg->where = where;
if (reg->when == UNW_WHEN_NEVER)
reg->when = when;
}
static void
alloc_spill_area (unsigned long *offp, unsigned long regsize,
struct unw_reg_info *lo, struct unw_reg_info *hi)
{
struct unw_reg_info *reg;
for (reg = hi; reg >= lo; --reg) {
if (reg->where == UNW_WHERE_SPILL_HOME) {
reg->where = UNW_WHERE_PSPREL;
*offp -= regsize;
reg->val = *offp;
}
}
}
static inline void
spill_next_when (struct unw_reg_info **regp, struct unw_reg_info *lim, unw_word t)
{
struct unw_reg_info *reg;
for (reg = *regp; reg <= lim; ++reg) {
if (reg->where == UNW_WHERE_SPILL_HOME) {
reg->when = t;
*regp = reg + 1;
return;
}
}
UNW_DPRINT(0, "unwind.%s: excess spill!\n", __func__);
}
static inline void
finish_prologue (struct unw_state_record *sr)
{
struct unw_reg_info *reg;
unsigned long off;
int i;
/*
* First, resolve implicit register save locations (see Section "11.4.2.3 Rules
* for Using Unwind Descriptors", rule 3):
*/
for (i = 0; i < (int) ARRAY_SIZE(unw.save_order); ++i) {
reg = sr->curr.reg + unw.save_order[i];
if (reg->where == UNW_WHERE_GR_SAVE) {
reg->where = UNW_WHERE_GR;
reg->val = sr->gr_save_loc++;
}
}
/*
* Next, compute when the fp, general, and branch registers get
* saved. This must come before alloc_spill_area() because
* we need to know which registers are spilled to their home
* locations.
*/
if (sr->imask) {
unsigned char kind, mask = 0, *cp = sr->imask;
int t;
static const unsigned char limit[3] = {
UNW_REG_F31, UNW_REG_R7, UNW_REG_B5
};
struct unw_reg_info *(regs[3]);
regs[0] = sr->curr.reg + UNW_REG_F2;
regs[1] = sr->curr.reg + UNW_REG_R4;
regs[2] = sr->curr.reg + UNW_REG_B1;
for (t = 0; t < sr->region_len; ++t) {
if ((t & 3) == 0)
mask = *cp++;
kind = (mask >> 2*(3-(t & 3))) & 3;
if (kind > 0)
spill_next_when(®s[kind - 1], sr->curr.reg + limit[kind - 1],
sr->region_start + t);
}
}
/*
* Next, lay out the memory stack spill area:
*/
if (sr->any_spills) {
off = sr->spill_offset;
alloc_spill_area(&off, 16, sr->curr.reg + UNW_REG_F2, sr->curr.reg + UNW_REG_F31);
alloc_spill_area(&off, 8, sr->curr.reg + UNW_REG_B1, sr->curr.reg + UNW_REG_B5);
alloc_spill_area(&off, 8, sr->curr.reg + UNW_REG_R4, sr->curr.reg + UNW_REG_R7);
}
}
/*
* Region header descriptors.
*/
static void
desc_prologue (int body, unw_word rlen, unsigned char mask, unsigned char grsave,
struct unw_state_record *sr)
{
int i, region_start;
if (!(sr->in_body || sr->first_region))
finish_prologue(sr);
sr->first_region = 0;
/* check if we're done: */
if (sr->when_target < sr->region_start + sr->region_len) {
sr->done = 1;
return;
}
region_start = sr->region_start + sr->region_len;
for (i = 0; i < sr->epilogue_count; ++i)
pop(sr);
sr->epilogue_count = 0;
sr->epilogue_start = UNW_WHEN_NEVER;
sr->region_start = region_start;
sr->region_len = rlen;
sr->in_body = body;
if (!body) {
push(sr);
for (i = 0; i < 4; ++i) {
if (mask & 0x8)
set_reg(sr->curr.reg + unw.save_order[i], UNW_WHERE_GR,
sr->region_start + sr->region_len - 1, grsave++);
mask <<= 1;
}
sr->gr_save_loc = grsave;
sr->any_spills = 0;
sr->imask = NULL;
sr->spill_offset = 0x10; /* default to psp+16 */
}
}
/*
* Prologue descriptors.
*/
static inline void
desc_abi (unsigned char abi, unsigned char context, struct unw_state_record *sr)
{
if (abi == 3 && context == 'i') {
sr->flags |= UNW_FLAG_INTERRUPT_FRAME;
UNW_DPRINT(3, "unwind.%s: interrupt frame\n", __func__);
}
else
UNW_DPRINT(0, "unwind%s: ignoring unwabi(abi=0x%x,context=0x%x)\n",
__func__, abi, context);
}
static inline void
desc_br_gr (unsigned char brmask, unsigned char gr, struct unw_state_record *sr)
{
int i;
for (i = 0; i < 5; ++i) {
if (brmask & 1)
set_reg(sr->curr.reg + UNW_REG_B1 + i, UNW_WHERE_GR,
sr->region_start + sr->region_len - 1, gr++);
brmask >>= 1;
}
}
static inline void
desc_br_mem (unsigned char brmask, struct unw_state_record *sr)
{
int i;
for (i = 0; i < 5; ++i) {
if (brmask & 1) {
set_reg(sr->curr.reg + UNW_REG_B1 + i, UNW_WHERE_SPILL_HOME,
sr->region_start + sr->region_len - 1, 0);
sr->any_spills = 1;
}
brmask >>= 1;
}
}
static inline void
desc_frgr_mem (unsigned char grmask, unw_word frmask, struct unw_state_record *sr)
{
int i;
for (i = 0; i < 4; ++i) {
if ((grmask & 1) != 0) {
set_reg(sr->curr.reg + UNW_REG_R4 + i, UNW_WHERE_SPILL_HOME,
sr->region_start + sr->region_len - 1, 0);
sr->any_spills = 1;
}
grmask >>= 1;
}
for (i = 0; i < 20; ++i) {
if ((frmask & 1) != 0) {
int base = (i < 4) ? UNW_REG_F2 : UNW_REG_F16 - 4;
set_reg(sr->curr.reg + base + i, UNW_WHERE_SPILL_HOME,
sr->region_start + sr->region_len - 1, 0);
sr->any_spills = 1;
}
frmask >>= 1;
}
}
static inline void
desc_fr_mem (unsigned char frmask, struct unw_state_record *sr)
{
int i;
for (i = 0; i < 4; ++i) {
if ((frmask & 1) != 0) {
set_reg(sr->curr.reg + UNW_REG_F2 + i, UNW_WHERE_SPILL_HOME,
sr->region_start + sr->region_len - 1, 0);
sr->any_spills = 1;
}
frmask >>= 1;
}
}
static inline void
desc_gr_gr (unsigned char grmask, unsigned char gr, struct unw_state_record *sr)
{
int i;
for (i = 0; i < 4; ++i) {
if ((grmask & 1) != 0)
set_reg(sr->curr.reg + UNW_REG_R4 + i, UNW_WHERE_GR,
sr->region_start + sr->region_len - 1, gr++);
grmask >>= 1;
}
}
static inline void
desc_gr_mem (unsigned char grmask, struct unw_state_record *sr)
{
int i;
for (i = 0; i < 4; ++i) {
if ((grmask & 1) != 0) {
set_reg(sr->curr.reg + UNW_REG_R4 + i, UNW_WHERE_SPILL_HOME,
sr->region_start + sr->region_len - 1, 0);
sr->any_spills = 1;
}
grmask >>= 1;
}
}
static inline void
desc_mem_stack_f (unw_word t, unw_word size, struct unw_state_record *sr)
{
set_reg(sr->curr.reg + UNW_REG_PSP, UNW_WHERE_NONE,
sr->region_start + min_t(int, t, sr->region_len - 1), 16*size);
}
static inline void
desc_mem_stack_v (unw_word t, struct unw_state_record *sr)
{
sr->curr.reg[UNW_REG_PSP].when = sr->region_start + min_t(int, t, sr->region_len - 1);
}
static inline void
desc_reg_gr (unsigned char reg, unsigned char dst, struct unw_state_record *sr)
{
set_reg(sr->curr.reg + reg, UNW_WHERE_GR, sr->region_start + sr->region_len - 1, dst);
}
static inline void
desc_reg_psprel (unsigned char reg, unw_word pspoff, struct unw_state_record *sr)
{
set_reg(sr->curr.reg + reg, UNW_WHERE_PSPREL, sr->region_start + sr->region_len - 1,
0x10 - 4*pspoff);
}
static inline void
desc_reg_sprel (unsigned char reg, unw_word spoff, struct unw_state_record *sr)
{
set_reg(sr->curr.reg + reg, UNW_WHERE_SPREL, sr->region_start + sr->region_len - 1,
4*spoff);
}
static inline void
desc_rp_br (unsigned char dst, struct unw_state_record *sr)
{
sr->return_link_reg = dst;
}
static inline void
desc_reg_when (unsigned char regnum, unw_word t, struct unw_state_record *sr)