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Diffstat (limited to 'sim/common/cgen-scache.c')
| -rw-r--r-- | sim/common/cgen-scache.c | 476 |
1 files changed, 0 insertions, 476 deletions
diff --git a/sim/common/cgen-scache.c b/sim/common/cgen-scache.c deleted file mode 100644 index 282497c5043..00000000000 --- a/sim/common/cgen-scache.c +++ /dev/null @@ -1,476 +0,0 @@ -/* Simulator cache routines for CGEN simulators (and maybe others). - Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc. - Contributed by Cygnus Support. - -This file is part of GDB, the GNU debugger. - -This program 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 2, or (at your option) -any later version. - -This program 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. - -You should have received a copy of the GNU General Public License along -with this program; if not, write to the Free Software Foundation, Inc., -59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ - -#define SCACHE_DEFINE_INLINE - -#include "sim-main.h" -#ifdef HAVE_STDLIB_H -#include <stdlib.h> -#endif -#include "libiberty.h" -#include "sim-options.h" -#include "sim-io.h" - -#define MAX(a,b) ((a) > (b) ? (a) : (b)) - -/* Unused address. */ -#define UNUSED_ADDR 0xffffffff - -/* Scache configuration parameters. - ??? Experiments to determine reasonable values is wip. - These are just guesses. */ - -/* Default number of scache elements. - The size of an element is typically 32-64 bytes, so the size of the - default scache will be between 512K and 1M bytes. */ -#ifdef CONFIG_SIM_CACHE_SIZE -#define SCACHE_DEFAULT_CACHE_SIZE CONFIG_SIM_CACHE_SIZE -#else -#define SCACHE_DEFAULT_CACHE_SIZE 16384 -#endif - -/* Minimum cache size. - The m32r port assumes a cache size of at least 2 so it can decode both 16 - bit insns. When compiling we need an extra for the chain entry. And this - must be a multiple of 2. Hence 4 is the minimum (though, for those with - featuritis or itchy pedantic bits, we could make this conditional on - WITH_SCACHE_PBB). */ -#define MIN_SCACHE_SIZE 4 - -/* Ratio of size of text section to size of scache. - When compiling, we don't want to flush the scache more than we have to - but we also don't want it to be exorbitantly(sp?) large. So we pick a high - default value, then reduce it by the size of the program being simulated, - but we don't override any value specified on the command line. - If not specified on the command line, the size to use is computed as - max (MIN_SCACHE_SIZE, - min (DEFAULT_SCACHE_SIZE, - text_size / (base_insn_size * INSN_SCACHE_RATIO))). */ -/* ??? Interesting idea but not currently used. */ -#define INSN_SCACHE_RATIO 4 - -/* Default maximum insn chain length. - The only reason for a maximum is so we can place a maximum size on the - profiling table. Chain lengths are determined by cti's. - 32 is a more reasonable number, but when profiling, the before/after - handlers take up that much more space. The scache is filled from front to - back so all this determines is when the scache needs to be flushed. */ -#define MAX_CHAIN_LENGTH 64 - -/* Default maximum hash list length. */ -#define MAX_HASH_CHAIN_LENGTH 4 - -/* Minimum hash table size. */ -#define MIN_HASH_CHAINS 32 - -/* Ratio of number of scache elements to number of hash lists. - Since the user can only specify the size of the scache, we compute the - size of the hash table as - max (MIN_HASH_CHAINS, scache_size / SCACHE_HASH_RATIO). */ -#define SCACHE_HASH_RATIO 8 - -/* Hash a PC value. - FIXME: May wish to make the hashing architecture specific. - FIXME: revisit */ -#define HASH_PC(pc) (((pc) >> 2) + ((pc) >> 5)) - -static MODULE_INIT_FN scache_init; -static MODULE_UNINSTALL_FN scache_uninstall; - -static DECLARE_OPTION_HANDLER (scache_option_handler); - -#define OPTION_PROFILE_SCACHE (OPTION_START + 0) - -static const OPTION scache_options[] = { - { {"scache-size", optional_argument, NULL, 'c'}, - 'c', "[SIZE]", "Specify size of simulator execution cache", - scache_option_handler }, -#if WITH_SCACHE_PBB - /* ??? It might be nice to allow the user to specify the size of the hash - table, the maximum hash list length, and the maximum chain length, but - for now that might be more akin to featuritis. */ -#endif - { {"profile-scache", optional_argument, NULL, OPTION_PROFILE_SCACHE}, - '\0', "on|off", "Perform simulator execution cache profiling", - scache_option_handler }, - { {NULL, no_argument, NULL, 0}, '\0', NULL, NULL, NULL } -}; - -static SIM_RC -scache_option_handler (SIM_DESC sd, sim_cpu *cpu, int opt, - char *arg, int is_command) -{ - switch (opt) - { - case 'c' : - if (WITH_SCACHE) - { - if (arg != NULL) - { - int n = strtol (arg, NULL, 0); - if (n < MIN_SCACHE_SIZE) - { - sim_io_eprintf (sd, "invalid scache size `%d', must be at least 4", n); - return SIM_RC_FAIL; - } - /* Ensure it's a multiple of 2. */ - if ((n & (n - 1)) != 0) - { - sim_io_eprintf (sd, "scache size `%d' not a multiple of 2\n", n); - { - /* round up to nearest multiple of 2 */ - int i; - for (i = 1; i < n; i <<= 1) - continue; - n = i; - } - sim_io_eprintf (sd, "rounding scache size up to %d\n", n); - } - if (cpu == NULL) - STATE_SCACHE_SIZE (sd) = n; - else - CPU_SCACHE_SIZE (cpu) = n; - } - else - { - if (cpu == NULL) - STATE_SCACHE_SIZE (sd) = SCACHE_DEFAULT_CACHE_SIZE; - else - CPU_SCACHE_SIZE (cpu) = SCACHE_DEFAULT_CACHE_SIZE; - } - } - else - sim_io_eprintf (sd, "Simulator execution cache not enabled, `--scache-size' ignored\n"); - break; - - case OPTION_PROFILE_SCACHE : - if (WITH_SCACHE && WITH_PROFILE_SCACHE_P) - { - /* FIXME: handle cpu != NULL. */ - return sim_profile_set_option (sd, "-scache", PROFILE_SCACHE_IDX, - arg); - } - else - sim_io_eprintf (sd, "Simulator cache profiling not compiled in, `--profile-scache' ignored\n"); - break; - } - - return SIM_RC_OK; -} - -SIM_RC -scache_install (SIM_DESC sd) -{ - sim_add_option_table (sd, NULL, scache_options); - sim_module_add_init_fn (sd, scache_init); - sim_module_add_uninstall_fn (sd, scache_uninstall); - - /* This is the default, it may be overridden on the command line. */ - STATE_SCACHE_SIZE (sd) = WITH_SCACHE; - - return SIM_RC_OK; -} - -static SIM_RC -scache_init (SIM_DESC sd) -{ - int c; - - for (c = 0; c < MAX_NR_PROCESSORS; ++c) - { - SIM_CPU *cpu = STATE_CPU (sd, c); - int elm_size = IMP_PROPS_SCACHE_ELM_SIZE (MACH_IMP_PROPS (CPU_MACH (cpu))); - - /* elm_size is 0 if the cpu doesn't not have scache support */ - if (elm_size == 0) - { - CPU_SCACHE_SIZE (cpu) = 0; - CPU_SCACHE_CACHE (cpu) = NULL; - } - else - { - if (CPU_SCACHE_SIZE (cpu) == 0) - CPU_SCACHE_SIZE (cpu) = STATE_SCACHE_SIZE (sd); - CPU_SCACHE_CACHE (cpu) = - (SCACHE *) xmalloc (CPU_SCACHE_SIZE (cpu) * elm_size); -#if WITH_SCACHE_PBB - CPU_SCACHE_MAX_CHAIN_LENGTH (cpu) = MAX_CHAIN_LENGTH; - CPU_SCACHE_NUM_HASH_CHAIN_ENTRIES (cpu) = MAX_HASH_CHAIN_LENGTH; - CPU_SCACHE_NUM_HASH_CHAINS (cpu) = MAX (MIN_HASH_CHAINS, - CPU_SCACHE_SIZE (cpu) - / SCACHE_HASH_RATIO); - CPU_SCACHE_HASH_TABLE (cpu) = - (SCACHE_MAP *) xmalloc (CPU_SCACHE_NUM_HASH_CHAINS (cpu) - * CPU_SCACHE_NUM_HASH_CHAIN_ENTRIES (cpu) - * sizeof (SCACHE_MAP)); - CPU_SCACHE_PBB_BEGIN (cpu) = (SCACHE *) zalloc (elm_size); - CPU_SCACHE_CHAIN_LENGTHS (cpu) = - (unsigned long *) zalloc ((CPU_SCACHE_MAX_CHAIN_LENGTH (cpu) + 1) - * sizeof (long)); -#endif - } - } - - scache_flush (sd); - - return SIM_RC_OK; -} - -static void -scache_uninstall (SIM_DESC sd) -{ - int c; - - for (c = 0; c < MAX_NR_PROCESSORS; ++c) - { - SIM_CPU *cpu = STATE_CPU (sd, c); - - if (CPU_SCACHE_CACHE (cpu) != NULL) - free (CPU_SCACHE_CACHE (cpu)); -#if WITH_SCACHE_PBB - if (CPU_SCACHE_HASH_TABLE (cpu) != NULL) - free (CPU_SCACHE_HASH_TABLE (cpu)); - if (CPU_SCACHE_PBB_BEGIN (cpu) != NULL) - free (CPU_SCACHE_PBB_BEGIN (cpu)); - if (CPU_SCACHE_CHAIN_LENGTHS (cpu) != NULL) - free (CPU_SCACHE_CHAIN_LENGTHS (cpu)); -#endif - } -} - -void -scache_flush (SIM_DESC sd) -{ - int c; - - for (c = 0; c < MAX_NR_PROCESSORS; ++c) - { - SIM_CPU *cpu = STATE_CPU (sd, c); - scache_flush_cpu (cpu); - } -} - -void -scache_flush_cpu (SIM_CPU *cpu) -{ - int i,n; - - /* Don't bother if cache not in use. */ - if (CPU_SCACHE_SIZE (cpu) == 0) - return; - -#if WITH_SCACHE_PBB - /* It's important that this be reasonably fast as this can be done when - the simulation is running. */ - CPU_SCACHE_NEXT_FREE (cpu) = CPU_SCACHE_CACHE (cpu); - n = CPU_SCACHE_NUM_HASH_CHAINS (cpu) * CPU_SCACHE_NUM_HASH_CHAIN_ENTRIES (cpu); - /* ??? Might be faster to just set the first entry, then update the - "last entry" marker during allocation. */ - for (i = 0; i < n; ++i) - CPU_SCACHE_HASH_TABLE (cpu) [i] . pc = UNUSED_ADDR; -#else - { - int elm_size = IMP_PROPS_SCACHE_ELM_SIZE (MACH_IMP_PROPS (CPU_MACH (cpu))); - SCACHE *sc; - - /* Technically, this may not be necessary, but it helps debugging. */ - memset (CPU_SCACHE_CACHE (cpu), 0, - CPU_SCACHE_SIZE (cpu) * elm_size); - - for (i = 0, sc = CPU_SCACHE_CACHE (cpu); i < CPU_SCACHE_SIZE (cpu); - ++i, sc = (SCACHE *) ((char *) sc + elm_size)) - { - sc->argbuf.addr = UNUSED_ADDR; - } - } -#endif -} - -#if WITH_SCACHE_PBB - -/* Look up PC in the hash table of scache entry points. - Returns the entry or NULL if not found. */ - -SCACHE * -scache_lookup (SIM_CPU *cpu, IADDR pc) -{ - /* FIXME: hash computation is wrong, doesn't take into account - NUM_HASH_CHAIN_ENTRIES. A lot of the hash table will be unused! */ - unsigned int slot = HASH_PC (pc) & (CPU_SCACHE_NUM_HASH_CHAINS (cpu) - 1); - int i, max_i = CPU_SCACHE_NUM_HASH_CHAIN_ENTRIES (cpu); - SCACHE_MAP *scm; - - /* We don't update hit/miss statistics as this is only used when recording - branch target addresses. */ - - scm = & CPU_SCACHE_HASH_TABLE (cpu) [slot]; - for (i = 0; i < max_i && scm->pc != UNUSED_ADDR; ++i, ++scm) - { - if (scm->pc == pc) - return scm->sc; - } - return 0; -} - -/* Look up PC and if not found create an entry for it. - If found the result is a pointer to the SCACHE entry. - If not found the result is NULL, and the address of a buffer of at least - N entries is stored in BUFP. - It's done this way so the caller can still distinguish found/not-found. - If the table is full, it is emptied to make room. - If the maximum length of a hash list is reached a random entry is thrown out - to make room. - ??? One might want to try to make this smarter, but let's see some - measurable benefit first. */ - -SCACHE * -scache_lookup_or_alloc (SIM_CPU *cpu, IADDR pc, int n, SCACHE **bufp) -{ - /* FIXME: hash computation is wrong, doesn't take into account - NUM_HASH_CHAIN_ENTRIES. A lot of the hash table will be unused! */ - unsigned int slot = HASH_PC (pc) & (CPU_SCACHE_NUM_HASH_CHAINS (cpu) - 1); - int i, max_i = CPU_SCACHE_NUM_HASH_CHAIN_ENTRIES (cpu); - SCACHE_MAP *scm; - SCACHE *sc; - - scm = & CPU_SCACHE_HASH_TABLE (cpu) [slot]; - for (i = 0; i < max_i && scm->pc != UNUSED_ADDR; ++i, ++scm) - { - if (scm->pc == pc) - { - PROFILE_COUNT_SCACHE_HIT (cpu); - return scm->sc; - } - } - PROFILE_COUNT_SCACHE_MISS (cpu); - - /* The address we want isn't cached. Bummer. - If the hash chain we have for this address is full, throw out an entry - to make room. */ - - if (i == max_i) - { - /* Rather than do something sophisticated like LRU, we just throw out - a semi-random entry. Let someone else have the joy of saying how - wrong this is. NEXT_FREE is the entry to throw out and cycles - through all possibilities. */ - static int next_free = 0; - - scm = & CPU_SCACHE_HASH_TABLE (cpu) [slot]; - /* FIXME: This seems rather clumsy. */ - for (i = 0; i < next_free; ++i, ++scm) - continue; - ++next_free; - if (next_free == CPU_SCACHE_NUM_HASH_CHAIN_ENTRIES (cpu)) - next_free = 0; - } - - /* At this point SCM points to the hash table entry to use. - Now make sure there's room in the cache. */ - /* FIXME: Kinda weird to use a next_free adjusted scm when cache is - flushed. */ - - { - int elm_size = IMP_PROPS_SCACHE_ELM_SIZE (MACH_IMP_PROPS (CPU_MACH (cpu))); - int elms_used = (((char *) CPU_SCACHE_NEXT_FREE (cpu) - - (char *) CPU_SCACHE_CACHE (cpu)) - / elm_size); - int elms_left = CPU_SCACHE_SIZE (cpu) - elms_used; - - if (elms_left < n) - { - PROFILE_COUNT_SCACHE_FULL_FLUSH (cpu); - scache_flush_cpu (cpu); - } - } - - sc = CPU_SCACHE_NEXT_FREE (cpu); - scm->pc = pc; - scm->sc = sc; - - *bufp = sc; - return NULL; -} - -#endif /* WITH_SCACHE_PBB */ - -/* Print cache access statics for CPU. */ - -void -scache_print_profile (SIM_CPU *cpu, int verbose) -{ - SIM_DESC sd = CPU_STATE (cpu); - unsigned long hits = CPU_SCACHE_HITS (cpu); - unsigned long misses = CPU_SCACHE_MISSES (cpu); - char buf[20]; - unsigned long max_val; - unsigned long *lengths; - int i; - - if (CPU_SCACHE_SIZE (cpu) == 0) - return; - - sim_io_printf (sd, "Simulator Cache Statistics\n\n"); - - /* One could use PROFILE_LABEL_WIDTH here. I chose not to. */ - sim_io_printf (sd, " Cache size: %s\n", - sim_add_commas (buf, sizeof (buf), CPU_SCACHE_SIZE (cpu))); - sim_io_printf (sd, " Hits: %s\n", - sim_add_commas (buf, sizeof (buf), hits)); - sim_io_printf (sd, " Misses: %s\n", - sim_add_commas (buf, sizeof (buf), misses)); - if (hits + misses != 0) - sim_io_printf (sd, " Hit rate: %.2f%%\n", - ((double) hits / ((double) hits + (double) misses)) * 100); - -#if WITH_SCACHE_PBB - sim_io_printf (sd, "\n"); - sim_io_printf (sd, " Hash table size: %s\n", - sim_add_commas (buf, sizeof (buf), CPU_SCACHE_NUM_HASH_CHAINS (cpu))); - sim_io_printf (sd, " Max hash list length: %s\n", - sim_add_commas (buf, sizeof (buf), CPU_SCACHE_NUM_HASH_CHAIN_ENTRIES (cpu))); - sim_io_printf (sd, " Max insn chain length: %s\n", - sim_add_commas (buf, sizeof (buf), CPU_SCACHE_MAX_CHAIN_LENGTH (cpu))); - sim_io_printf (sd, " Cache full flushes: %s\n", - sim_add_commas (buf, sizeof (buf), CPU_SCACHE_FULL_FLUSHES (cpu))); - sim_io_printf (sd, "\n"); - - if (verbose) - { - sim_io_printf (sd, " Insn chain lengths:\n\n"); - max_val = 0; - lengths = CPU_SCACHE_CHAIN_LENGTHS (cpu); - for (i = 1; i < CPU_SCACHE_MAX_CHAIN_LENGTH (cpu); ++i) - if (lengths[i] > max_val) - max_val = lengths[i]; - for (i = 1; i < CPU_SCACHE_MAX_CHAIN_LENGTH (cpu); ++i) - { - sim_io_printf (sd, " %2d: %*s: ", - i, - max_val < 10000 ? 5 : 10, - sim_add_commas (buf, sizeof (buf), lengths[i])); - sim_profile_print_bar (sd, PROFILE_HISTOGRAM_WIDTH, - lengths[i], max_val); - sim_io_printf (sd, "\n"); - } - sim_io_printf (sd, "\n"); - } -#endif /* WITH_SCACHE_PBB */ -} |