diff --git a/src/ia64/Gscript-ia64.c b/src/ia64/Gscript-ia64.c index e69de29b..f1d80277 100644 --- a/src/ia64/Gscript-ia64.c +++ b/src/ia64/Gscript-ia64.c @@ -0,0 +1,532 @@ +/* libunwind - a platform-independent unwind library + Copyright (C) 2001-2002 Hewlett-Packard Co + Contributed by David Mosberger-Tang + +This file is part of libunwind. + +Permission is hereby granted, free of charge, to any person obtaining +a copy of this software and associated documentation files (the +"Software"), to deal in the Software without restriction, including +without limitation the rights to use, copy, modify, merge, publish, +distribute, sublicense, and/or sell copies of the Software, and to +permit persons to whom the Software is furnished to do so, subject to +the following conditions: + +The above copyright notice and this permission notice shall be +included in all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE +LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ + +#include "offsets.h" +#include "rse.h" +#include "unwind_i.h" + +#ifdef HAVE___THREAD +static __thread struct ia64_script_cache ia64_per_thread_cache; +#endif + +static inline unw_hash_index_t +hash (unw_word_t ip) +{ +# define magic 0x9e3779b97f4a7c16 /* based on (sqrt(5)/2-1)*2^64 */ + + return (ip >> 4) * magic >> (64 - IA64_LOG_UNW_HASH_SIZE); +} + +static inline long +cache_match (struct ia64_script *script, unw_word_t ip, unw_word_t pr) +{ + /* XXX lock script cache */ + if (ip == script->ip && ((pr ^ script->pr_val) & script->pr_mask) == 0) + /* keep the lock... */ + return 1; + /* XXX unlock script cache */ + return 0; +} + +static inline void +flush_script_cache (unw_addr_space_t as, struct ia64_script_cache *cache) +{ + int i; + + for (i = 0; i < IA64_UNW_CACHE_SIZE; ++i) + cache->buckets[i].ip = 0; + + cache->generation = as->cache_generation; +} + +static inline struct ia64_script_cache * +get_script_cache (unw_addr_space_t as) +{ + struct ia64_script_cache *cache = &as->global_cache; + +#ifdef HAVE___THREAD + if (as->caching_policy == UNW_CACHE_PER_THREAD) + cache = &ia64_per_thread_cache; +#endif + + if (as->cache_generation != cache->generation) + flush_script_cache (as, cache); + + return cache; +} + +static struct ia64_script * +script_lookup (struct ia64_script_cache *cache, struct cursor *c) +{ + struct ia64_script *script = cache->buckets + c->hint; + unsigned short index; + unw_word_t ip, pr; + + ip = c->ip; + pr = c->pr; + + if (cache_match (script, ip, pr)) + return script; + + index = cache->hash[hash (ip)]; + if (index >= IA64_UNW_CACHE_SIZE) + return 0; + + script = cache->buckets + index; + while (1) + { + if (cache_match (script, ip, pr)) + { + /* update hint; no locking needed: single-word writes are atomic */ + c->hint = cache->buckets[c->prev_script].hint = + (script - cache->buckets); + return script; + } + if (script->coll_chain >= IA64_UNW_HASH_SIZE) + return 0; + script = cache->buckets + script->coll_chain; + } +} + +HIDDEN struct ia64_script * +ia64_script_lookup (struct cursor *c) +{ + return script_lookup (get_script_cache (c->as), c); +} + +/* On returning, the lock for the SCRIPT is still being held. */ + +static inline struct ia64_script * +script_new (struct ia64_script_cache *cache, unw_word_t ip) +{ + struct ia64_script *script, *prev, *tmp; + unw_hash_index_t index; + unsigned short head; + + /* XXX lock hash table */ + { + head = cache->lru_head; + script = cache->buckets + head; + cache->lru_head = script->lru_chain; + } + /* XXX unlock hash table */ + + /* XXX We'll deadlock here if we interrupt a thread that is holding + the script->lock. */ + /* XXX lock script */ + + /* XXX lock unwind data lock */ + { + /* re-insert script at the tail of the LRU chain: */ + cache->buckets[cache->lru_tail].lru_chain = head; + cache->lru_tail = head; + + /* remove the old script from the hash table (if it's there): */ + if (script->ip) + { + index = hash (script->ip); + tmp = cache->buckets + cache->hash[index]; + prev = 0; + while (1) + { + if (tmp == script) + { + if (prev) + prev->coll_chain = tmp->coll_chain; + else + cache->hash[index] = tmp->coll_chain; + break; + } + else + prev = tmp; + if (tmp->coll_chain >= IA64_UNW_CACHE_SIZE) + /* old script wasn't in the hash-table */ + break; + tmp = cache->buckets + tmp->coll_chain; + } + } + + /* enter new script in the hash table */ + index = hash (ip); + script->coll_chain = cache->hash[index]; + cache->hash[index] = script - cache->buckets; + + script->ip = ip; /* set new IP while we're holding the locks */ + } + /* XXX unlock unwind data lock */ + + script->hint = 0; + script->count = 0; + return script; +} + +static inline void +script_finalize (struct ia64_script *script, struct cursor *c, + struct ia64_state_record *sr) +{ + script->pr_mask = sr->pr_mask; + script->pr_val = sr->pr_val; + script->pi = c->pi; +} + +static inline void +script_emit (struct ia64_script *script, struct ia64_script_insn insn) +{ + if (script->count >= IA64_MAX_SCRIPT_LEN) + { + dprintf ("%s: script exceeds maximum size of %u instructions!\n", + __FUNCTION__, IA64_MAX_SCRIPT_LEN); + return; + } + script->insn[script->count++] = insn; +} + +static inline void +emit_nat_info (struct ia64_state_record *sr, int i, struct ia64_script *script) +{ + struct ia64_reg_info *r = sr->curr.reg + i; + struct ia64_script_insn insn; + enum ia64_script_insn_opcode opc = IA64_INSN_SET; + unsigned long val = 0; + + switch (r->where) + { + case IA64_WHERE_GR: + val = IA64_LOC (r->val, 0); + break; + + case IA64_WHERE_FR: + val = 0; /* value doesn't matter... */ + break; + + case IA64_WHERE_BR: + val = IA64_LOC (0, 0); /* no NaT bit */ + break; + + case IA64_WHERE_PSPREL: + case IA64_WHERE_SPREL: + opc = IA64_INSN_SETNAT_MEMSTK; + break; + + default: + dprintf ("%s: don't know how to emit nat info for where = %u\n", + __FUNCTION__, r->where); + return; + } + insn.opc = opc; + insn.dst = unw.preg_index[i]; + insn.val = val; + script_emit (script, insn); +} + +static void +compile_reg (struct ia64_state_record *sr, int i, struct ia64_script *script) +{ + struct ia64_reg_info *r = sr->curr.reg + i; + enum ia64_script_insn_opcode opc; + unsigned long val, rval; + struct ia64_script_insn insn; + long is_preserved_gr; + + if (r->where == IA64_WHERE_NONE || r->when >= sr->when_target) + return; + + opc = IA64_INSN_MOVE; + val = rval = r->val; + is_preserved_gr = (i >= IA64_REG_R4 && i <= IA64_REG_R7); + + switch (r->where) + { + case IA64_WHERE_GR: + if (rval >= 32) + { + /* register got spilled to a stacked register */ + opc = IA64_INSN_MOVE_STACKED; + val = rval - 32; + } + else if (rval >= 4 && rval <= 7) + /* register got spilled to a preserved register */ + val = unw.preg_index[IA64_REG_R4 + (rval - 4)]; + else + { + /* register got spilled to a scratch register */ + opc = IA64_INSN_MOVE_SCRATCH; + val = UNW_IA64_GR + rval; + } + break; + + case IA64_WHERE_FR: + if (rval <= 5) + val = unw.preg_index[IA64_REG_F2 + (rval - 1)]; + else if (rval >= 16 && rval <= 31) + val = unw.preg_index[IA64_REG_F16 + (rval - 16)]; + else + { + opc = IA64_INSN_MOVE_SCRATCH; + val = UNW_IA64_FR + rval; + } + break; + + case IA64_WHERE_BR: + if (rval >= 1 && rval <= 5) + val = unw.preg_index[IA64_REG_B1 + (rval - 1)]; + else + { + opc = IA64_INSN_MOVE_SCRATCH; + val = UNW_IA64_BR + rval; + } + break; + + case IA64_WHERE_SPREL: + opc = IA64_INSN_ADD_SP; + if (i >= IA64_REG_F2 && i <= IA64_REG_F31) + val |= IA64_LOC_TYPE_FP; + break; + + case IA64_WHERE_PSPREL: + opc = IA64_INSN_ADD_PSP; + if (i >= IA64_REG_F2 && i <= IA64_REG_F31) + val |= IA64_LOC_TYPE_FP; + break; + + default: + dprintf ("%s: register %u has unexpected `where' value of %u\n", + __FUNCTION__, i, r->where); + break; + } + insn.opc = opc; + insn.dst = unw.preg_index[i]; + insn.val = val; + script_emit (script, insn); + if (is_preserved_gr) + emit_nat_info (sr, i, script); + + if (i == IA64_REG_PSP) + { + /* info->psp must contain the _value_ of the previous sp, not + it's save location. We get this by dereferencing the value + we just stored in info->psp: */ + insn.opc = IA64_INSN_LOAD; + insn.dst = insn.val = unw.preg_index[IA64_REG_PSP]; + script_emit (script, insn); + } +} + +/* Build an unwind script that unwinds from state OLD_STATE to the + entrypoint of the function that called OLD_STATE. */ + +static inline int +build_script (struct cursor *c, struct ia64_script *script) +{ + struct ia64_state_record sr; + struct ia64_script_insn insn; + int i, ret; + + ret = ia64_create_state_record (c, &sr); + if (ret < 0) + return ret; + + /* First, set psp if we're dealing with a fixed-size frame; + subsequent instructions may depend on this value. */ + if (sr.when_target > sr.curr.reg[IA64_REG_PSP].when + && (sr.curr.reg[IA64_REG_PSP].where == IA64_WHERE_NONE) + && sr.curr.reg[IA64_REG_PSP].val != 0) + { + /* new psp is psp plus frame size */ + insn.opc = IA64_INSN_ADD; + insn.dst = struct_offset (struct cursor, psp) / 8; + insn.val = sr.curr.reg[IA64_REG_PSP].val; /* frame size */ + script_emit (script, insn); + } + + /* determine where the primary UNaT is: */ + if (sr.when_target < sr.curr.reg[IA64_REG_PRI_UNAT_GR].when) + i = IA64_REG_PRI_UNAT_MEM; + else if (sr.when_target < sr.curr.reg[IA64_REG_PRI_UNAT_MEM].when) + i = IA64_REG_PRI_UNAT_GR; + else if (sr.curr.reg[IA64_REG_PRI_UNAT_MEM].when > + sr.curr.reg[IA64_REG_PRI_UNAT_GR].when) + i = IA64_REG_PRI_UNAT_MEM; + else + i = IA64_REG_PRI_UNAT_GR; + + compile_reg (&sr, i, script); + + for (i = IA64_REG_BSP; i < IA64_NUM_PREGS; ++i) + compile_reg (&sr, i, script); + + if (sr.is_signal_frame) + { + insn.opc = IA64_INSN_SET; + insn.dst = struct_offset (struct cursor, is_signal_frame) / 8; + insn.val = 1; + script_emit (script, insn); + } + + script_finalize (script, c, &sr); + + ia64_free_state_record (&sr); + return 0; +} + +/* Apply the unwinding actions represented by OPS and update SR to + reflect the state that existed upon entry to the function that this + unwinder represents. */ + +static inline int +run_script (struct ia64_script *script, struct cursor *c) +{ + struct ia64_script_insn *ip, *limit, next_insn; + unw_word_t val, unat_addr, *s = (unw_word_t *) c; + unsigned long opc, dst; + int ret; + + c->pi = script->pi; + ip = script->insn; + limit = script->insn + script->count; + next_insn = *ip; + + while (ip++ < limit) + { + opc = next_insn.opc; + dst = next_insn.dst; + val = next_insn.val; + next_insn = *ip; + + switch (opc) + { + case IA64_INSN_SET: + s[dst] = val; + break; + + case IA64_INSN_ADD: + s[dst] += val; + break; + + case IA64_INSN_ADD_PSP: + s[dst] = c->psp + val; + break; + + case IA64_INSN_ADD_SP: + s[dst] = c->sp + val; + break; + + case IA64_INSN_MOVE: + s[dst] = s[val]; + break; + + case IA64_INSN_MOVE_SCRATCH: + s[dst] = ia64_scratch_loc (c, val); + break; + + case IA64_INSN_MOVE_STACKED: + s[dst] = ia64_rse_skip_regs (c->bsp, val); + break; + + case IA64_INSN_SETNAT_MEMSTK: + ret = ia64_get (c, c->pri_unat_loc, &unat_addr); + if (ret < 0) + return ret; + s[dst] = IA64_LOC (unat_addr >> 3, IA64_LOC_TYPE_MEMSTK_NAT); + break; + + case IA64_INSN_LOAD: + ret = ia64_get (c, s[val], &s[dst]); + if (ret < 0) + return ret; + break; + } + } + return 0; +} + +HIDDEN int +ia64_find_save_locs (struct cursor *c) +{ + struct ia64_script *script = NULL; + int ret = 0; + + if (c->as->caching_policy == UNW_CACHE_NONE) + { + struct ia64_script tmp_script; + + script = &tmp_script; + script->ip = c->ip; + script->hint = 0; + script->count = 0; + ret = build_script (c, script); + } + else + { + struct ia64_script_cache *cache = get_script_cache (c->as); + + script = script_lookup (cache, c); + if (!script) + { + script = script_new (cache, c->ip); + if (!script) + { + dprintf ("%s: failed to create unwind script\n", __FUNCTION__); + return -UNW_EUNSPEC; + } + cache->buckets[c->prev_script].hint = script - cache->buckets; + + ret = build_script (c, script); + } + c->hint = script->hint; + c->prev_script = script - cache->buckets; + } + if (ret < 0) + { + if (ret != UNW_ESTOPUNWIND) + dprintf ("%s: failed to locate/build unwind script for ip %lx\n", + __FUNCTION__, (long) c->ip); + return ret; + } + run_script (script, c); + return 0; +} + +HIDDEN void +ia64_script_cache_init (struct ia64_script_cache *cache) +{ + int i; + + cache->lru_head = IA64_UNW_CACHE_SIZE - 1; + cache->lru_tail = 0; + + for (i = 0; i < IA64_UNW_CACHE_SIZE; ++i) + { + if (i > 0) + cache->buckets[i].lru_chain = (i - 1); + cache->buckets[i].coll_chain = -1; +#if 0 + /* must be lock-free! */ + unw.cache[i].lock = RW_LOCK_UNLOCKED; +#endif + } + for (i = 0; ihash[i] = -1; +}