From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Berlin To: "Peter.Schauer" Cc: gdb@sources.redhat.com, gdb-patches@sources.redhat.com Subject: Re: Removal of demangled names from partial symbols Date: Mon, 04 Dec 2000 14:13:00 -0000 Message-id: References: <200012042053.VAA28364@reisser.regent.e-technik.tu-muenchen.de> X-SW-Source: 2000-12/msg00084.html On Mon, 4 Dec 2000, Peter.Schauer wrote: > : Why do we not do a lookup_minimal_symbol in > : a new function, add_psymbol_and_dem_name_to_list, on the mangled name, > : and if we get back a symbol, use the demangled name from that, > : otherwise, demangle it. > > For some symbol formats (e.g. a.out) the linkage and debugging symbols are > intermixed. By the time you want to record a partial symbol, the minimal > symbol might have not been seen yet. Or the minimal symbol has been seen, > but the minimal symbols are not yet installed, so lookup_minimal_symbol > will fail. > So i could just use the mapping structure i describe below, and have both SYMBOL_INIT_DEMANGLED_NAME, et al (IE all the ways we init the demangled name) attempt to look up the mangled name in it to see if we've demangled it before. Then it wouldn't matter what order this happened it. > You might be able to work around this by going over all psymbols and fill > in the demangled name via lookup_minimal_symbol _after_ the minimal symbols > are installed, but I am not yet convinced that you don't have to pay your > price on slower systems. After all, 5 secs to 6 secs is a 20% slowdown. Except we already pay the price on ELF, where unless you've stripped it, your minsyms contain just about all the symbols used in the program. It's also an issue of saving ~50% of the memory we use now (Remember, the slowdown comes from the bcaching, which would also not be necessary with the mapping structure), and making lookups dramatically faster. Without the bcaching, profiling shows all the time being used because the lookup_minimal symbol, as you would expect. Further analysis shows msymbol_hash_iw function isn't very good, and even if it was perfect we have 379 buckets, total, per object file, so on 100000 symbols, most concentrated in one object file (the main program in this case, which has 100 meg of debug info, and 100k symbols) ,we have chains with an average length of 286. If we assume we have to search half those, we are doing 143 strcmps to find the minimal symbol to get the demangled name out of. The ternary search tree i propose would require the equivalent of one strcmp to find the name. Users i've talked to are more annoyed that once gdb gets going, it takes for ever to do anything, because the symbol lookups take so long, than they are that gdb takes 3 minutes vs 3 minutes, 30 seconds, to start up. Let me finish integrating the mapping structure (I have the ternary search tree in libiberty, in case others wanted to use it), and do some tests to see how much faster it is. --Dan >From ac131313@cygnus.com Mon Dec 04 14:31:00 2000 From: Andrew Cagney To: Doug Evans Cc: Ben Elliston , gdb-patches@sources.redhat.com, cgen@sources.redhat.com Subject: Re: [Sim] Patch to sim/common/cgen-ops.h Date: Mon, 04 Dec 2000 14:31:00 -0000 Message-id: <3A2C1907.1D45F29E@cygnus.com> References: <14891.9921.841994.631587@casey.transmeta.com> <14891.59391.397233.55439@casey.transmeta.com> X-SW-Source: 2000-12/msg00085.html Content-length: 1636 Doug Evans wrote: > Andrew may have just been refering to the name choice used in the > generated code. Either way, this is just a naming choice issue. > I like the current scheme. Kind of. My understanding is that there are three type systems kicking around: host target abstract host: This is the compiler on which the system is being run. It has types such as int, long, unsigned, ... Their semantics are host platform dependant target: This is the type system of the target. At one level there are the types for the target compiler (eg int which could be 16 bits). At another level there are the concrete semantics of specific operations. abstract/portable: For sim/common (which took things from PPC). This was a type system that was platform independant. The semantics of something like: unsigned64 = (signed32) val; were well defined. It is more fully: unsigned64 = (unsigned64)(signed64)(signed32) val; The two important things were that: o The semantics were not tied to either the host or the target. Instead they are defined abstractly. o It used a very standard convention. C9x adopted int8 etc. Some have used __u8 et.al. Programmers are going to be instantly familar with such a convention. They are going to simply be bamboozled by a more obscure SI, DI, et.al. convention. sim/common used signed8 et.al. I've more recently seen a suggestion for S8, U16, et.al. I think there are strong technical arguments for avoiding the SI, DI convention and instead using an abstract type system that more clearly defines its own semantics. enjoy, Andrew >From cgd@sibyte.com Mon Dec 04 14:43:00 2000 From: cgd@sibyte.com (Chris G. Demetriou) To: gdb-patches@sourceware.cygnus.com Cc: ehs@sibyte.com Subject: sim/igen: add gen-delay-slot generation option Date: Mon, 04 Dec 2000 14:43:00 -0000 Message-id: <5tg0k3ajun.fsf@highland.sibyte.com> X-SW-Source: 2000-12/msg00086.html Content-length: 19973 The patch below: (1) adds a new simulator generation option to igen, "gen-delay-slot". This new option generates PC pipe manipulation operations in a way that can be used to cleanly and correctly model MIPS branch delay slots. (2) changes the generated code so that any wired-zero registers are cleared by common code (shared by all of the opcodes), rather than by each individual opcode's implementation. The changes were implemented by a coworker, Ed Satterthwaite (who's CC'd on this message), then cleaned up for submission by me. We've both got assignment paperwork on file. I've tested this in the manner described in the message I recently sent: http://sources.redhat.com/ml/gdb/2000-12/msg00015.html It doesn't change any test output for any of the targets there (several of which -- all but fr30 and sparclite -- seem to successfully run things through the resulting 'run' binaries). This doesn't surprise me; as you would see by looking at the code, (1) doesn't change the code unless you've specified the new option, and (2) does changes the code in a fairly straightforward way. 8-) goes in sim/igen. 2000-12-02 Ed Satterthwaite ehs@sibyte.com and Chris Demetriou cgd@sibyte.com * igen.c (main): Add gen-delay-slot option. (print_semantic_function_formal, print_semantic_function_actual, print_icache_function_formal, print_icache_function_actual): Implement gen-delay-slot option. * igen.h (_igen_gen_options): Add delay_slot member. * gen-engine.c (print_register_clear): New function used to handle gen-zero-r option. (print_run_body): Implement gen-delay-slot option. Use print_register_clear. (print_jump_body): Use print_register_clear. * gen-semantics.c (print_semantic_body): Implement gen-delay-slot option. Delete old code to handle gen-zero-r option. * gen-support.c (print_support_function_name, gen_support_h): Implement gen-delay-slot option. * ld-insn.c (option_names, option_map, parse_option_record): Implement gen-delay-slot option. chris =================================================================== Index: gen-engine.c =================================================================== RCS file: /cvs/src/src/sim/igen/gen-engine.c,v retrieving revision 1.1.1.1 diff -c -p -r1.1.1.1 gen-engine.c *** gen-engine.c 1999/04/16 01:35:04 1.1.1.1 --- gen-engine.c 2000/12/03 00:22:02 *************** print_engine_issue_postfix_hook (lf *fil *** 66,71 **** --- 66,85 ---- static void + print_register_clear (lf *file) + { + /* Architecture expects a REG to be zero. Instead of having to + check every read to see if it is refering to that REG just zap it + at the start of every instruction */ + if (options.gen.zero_reg) + { + lf_printf (file, "/* Architecture expects REG to be zero */\n"); + lf_printf (file, "GPR_CLEAR(%d);\n", options.gen.zero_reg_nr); + lf_printf (file, "\n"); + } + } + + static void print_run_body (lf *file, gen_entry *table) { *************** print_run_body (lf *file, *** 84,89 **** --- 98,107 ---- lf_printf (file, "%sinstruction_address cia;\n", options.module.global.prefix.l); } lf_printf (file, "int current_cpu = next_cpu_nr;\n"); + if (!options.gen.smp && options.gen.delay_slot) + { + lf_putstr (file, "sim_cpu *cpu = STATE_CPU (sd, current_cpu);\n"); + } if (options.gen.icache) { *************** In this case, we can take advantage of t *** 105,113 **** instruction address (CIA) does not need to be read from / written to the CPU object after the execution of an instruction. ! Instead, CIA is only saved when the main loop exits. This occures ! when either sim_engine_halt or sim_engine_restart is called. Both of ! these functions save the current instruction address before halting / restarting the simulator. As a variation, there may also be support for an instruction cracking --- 123,131 ---- instruction address (CIA) does not need to be read from / written to the CPU object after the execution of an instruction. ! CIA is only saved when the main loop exits. This occurs when either ! sim_engine_halt or sim_engine_restart is called. Both of these ! functions save the current instruction address before halting / restarting the simulator. As a variation, there may also be support for an instruction cracking *************** cache. */ *** 120,126 **** lf_putstr (file, "SIM_ASSERT (current_cpu == 0);\n"); lf_putstr (file, "SIM_ASSERT (nr_cpus == 1);\n"); lf_putstr (file, "cia = CIA_GET (CPU);\n"); - lf_putstr (file, "\n"); lf_putstr (file, "while (1)\n"); lf_putstr (file, " {\n"); --- 138,143 ---- *************** cache. */ *** 132,141 **** lf_printf (file, "\n"); if (!options.gen.icache) { ! lf_printf (file, "%sinstruction_word instruction_0 = IMEM%d (cia);\n", options.module.global.prefix.l, options.insn_bit_size); print_engine_issue_prefix_hook (file); print_idecode_body (file, table, "nia = "); print_engine_issue_postfix_hook (file); } --- 149,168 ---- lf_printf (file, "\n"); if (!options.gen.icache) { ! if (options.gen.delay_slot) ! { ! lf_printf (file, "%sinstruction_word instruction_0;\n", ! options.module.global.prefix.l); ! lf_putstr (file, "\n"); ! lf_printf (file, "instruction_0 = IMEM%d (cia);\n", ! options.insn_bit_size); ! } ! else ! lf_printf (file, "%sinstruction_word instruction_0 = IMEM%d (cia);\n", options.module.global.prefix.l, options.insn_bit_size); print_engine_issue_prefix_hook (file); + print_register_clear (file); print_idecode_body (file, table, "nia = "); print_engine_issue_postfix_hook (file); } *************** cache. */ *** 169,174 **** --- 196,202 ---- lf_putstr (file, "{\n"); lf_indent (file, +2); print_engine_issue_prefix_hook (file); + print_register_clear (file); print_idecode_body (file, table, "nia ="); print_engine_issue_postfix_hook (file); lf_indent (file, -2); *************** cache. */ *** 177,182 **** --- 205,211 ---- else { print_engine_issue_prefix_hook (file); + print_register_clear (file); print_idecode_body (file, table, "semantic ="); lf_putstr (file, "nia = semantic (cpu, cache_entry, cia);\n"); print_engine_issue_postfix_hook (file); *************** cache. */ *** 197,202 **** --- 226,235 ---- case nia_is_invalid: ERROR ("engine gen when NIA complex"); } + if (options.gen.delay_slot) + { + lf_printf (file, "CLOCK_PC_PIPE (cpu);\n"); + } /* events */ lf_putstr (file, "\n"); *************** after all the other CPU's and the event *** 230,259 **** lf_printf (file, "SIM_ASSERT (current_cpu >= 0);\n"); lf_printf (file, "SIM_ASSERT (current_cpu <= nr_cpus - 1);\n"); lf_printf (file, "SIM_ASSERT (nr_cpus <= MAX_NR_PROCESSORS);\n"); - lf_putstr (file, "\n"); lf_putstr (file, "while (1)\n"); lf_putstr (file, " {\n"); lf_indent (file, +4); lf_putstr (file, "sim_cpu *cpu = STATE_CPU (sd, current_cpu);\n"); ! lf_putstr (file, "instruction_address cia = CIA_GET (cpu);\n"); ! lf_putstr (file, "\n"); if (!options.gen.icache) { ! lf_printf (file, "instruction_word instruction_0 = IMEM%d (cia);\n", ! options.insn_bit_size); print_engine_issue_prefix_hook (file); ! print_idecode_body (file, table, "cia ="); ! lf_putstr (file, "CIA_SET (cpu, cia);\n"); print_engine_issue_postfix_hook (file); } if (options.gen.icache) { ! lf_putstr (file, "engine_cache *cache_entry =\n"); ! lf_putstr (file, " cpu_icache_entry(processor, cia);\n"); ! lf_putstr (file, "\n"); lf_putstr (file, "if (cache_entry->address == cia) {\n"); { lf_indent (file, +2); --- 263,324 ---- lf_printf (file, "SIM_ASSERT (current_cpu >= 0);\n"); lf_printf (file, "SIM_ASSERT (current_cpu <= nr_cpus - 1);\n"); lf_printf (file, "SIM_ASSERT (nr_cpus <= MAX_NR_PROCESSORS);\n"); lf_putstr (file, "\n"); + lf_putstr (file, "while (1)\n"); lf_putstr (file, " {\n"); lf_indent (file, +4); lf_putstr (file, "sim_cpu *cpu = STATE_CPU (sd, current_cpu);\n"); ! if (options.gen.delay_slot) ! { ! lf_putstr (file, "\n"); ! lf_putstr (file, "if (! RESET (cpu))\n"); ! lf_putstr (file, " {\n"); ! lf_indent (file, +4); ! lf_putstr (file, "instruction_address cia;\n"); ! } ! else ! lf_putstr (file, "instruction_address cia = CIA_GET (cpu);\n"); if (!options.gen.icache) { ! if (options.gen.delay_slot) ! { ! lf_printf (file, "instruction_word instruction_0;\n"); ! lf_putstr (file, "\n"); ! lf_printf (file, "cia = CIA_GET (cpu);\n"); ! lf_printf (file, "instruction_0 = IMEM%d (cia);\n", ! options.insn_bit_size); ! } ! else ! lf_printf (file, "instruction_word instruction_0 = IMEM%d (cia);\n", ! options.insn_bit_size); print_engine_issue_prefix_hook (file); ! print_register_clear (file); ! print_idecode_body (file, table, "cia = "); print_engine_issue_postfix_hook (file); + lf_putstr (file, "CIA_SET (cpu, cia);\n"); + if (options.gen.delay_slot) + { + lf_printf (file, "CLOCK_PC_PIPE (cpu);\n"); + } } if (options.gen.icache) { ! if (options.gen.delay_slot) ! { ! lf_putstr (file, "engine_cache *cache_entry;\n"); ! lf_putstr (file, "\n"); ! lf_printf (file, "cia = CIA_GET (cpu);\n"); ! lf_putstr (file, "cache_entry = cpu_icache_entry(processor, cia);\n"); ! } ! else ! { ! lf_putstr (file, "engine_cache *cache_entry =\n"); ! lf_putstr (file, " cpu_icache_entry(processor, cia);\n"); ! lf_putstr (file, "\n"); ! } lf_putstr (file, "if (cache_entry->address == cia) {\n"); { lf_indent (file, +2); *************** after all the other CPU's and the event *** 285,290 **** --- 350,356 ---- lf_putstr (file, "{\n"); lf_indent (file, +2); print_engine_issue_prefix_hook (file); + print_register_clear (file); print_idecode_body(file, table, "cia ="); print_engine_issue_postfix_hook (file); lf_indent (file, -2); *************** after all the other CPU's and the event *** 293,298 **** --- 359,365 ---- else { print_engine_issue_prefix_hook (file); + print_register_clear (file); print_idecode_body(file, table, "semantic = "); lf_putstr (file, "cia = semantic(processor, cache_entry, cia);\n"); print_engine_issue_postfix_hook (file); *************** after all the other CPU's and the event *** 305,310 **** --- 372,382 ---- lf_putstr (file, "}\n"); } + if (options.gen.delay_slot) + { + lf_indent (file, -4); + lf_putstr (file, " }\n"); + } lf_putstr (file, "\n"); lf_putstr (file, "current_cpu += 1;\n"); lf_putstr (file, "if (current_cpu == nr_cpus)\n"); *************** print_jump_body (lf *file, *** 653,663 **** lf_indent (file, +1); } ! print_engine_issue_prefix_hook (file); lf_putstr (file, "instruction\n"); lf_putstr (file, " = vm_instruction_map_read(cpu_instruction_map(processor),\n"); lf_putstr (file, " processor, nia);\n"); print_engine_issue_prefix_hook (file); print_idecode_body (file, entry, "/*IGORE*/"); print_engine_issue_postfix_hook (file); --- 725,736 ---- lf_indent (file, +1); } ! print_engine_issue_prefix_hook (file); /* XXX also 4 lines below? */ lf_putstr (file, "instruction\n"); lf_putstr (file, " = vm_instruction_map_read(cpu_instruction_map(processor),\n"); lf_putstr (file, " processor, nia);\n"); print_engine_issue_prefix_hook (file); + print_register_clear (file); print_idecode_body (file, entry, "/*IGORE*/"); print_engine_issue_postfix_hook (file); Index: gen-semantics.c =================================================================== RCS file: /cvs/src/src/sim/igen/gen-semantics.c,v retrieving revision 1.2 diff -c -p -r1.2 gen-semantics.c *** gen-semantics.c 2000/05/29 19:28:53 1.2 --- gen-semantics.c 2000/12/03 00:22:02 *************** print_semantic_body (lf *file, *** 219,226 **** } else { ! lf_printf (file, "nia = cia + %d;\n", ! options.insn_bit_size / 8); } } } --- 219,233 ---- } else { ! if (options.gen.delay_slot) ! { ! lf_printf (file, "nia = NIA_GET (CPU); "); ! lf_printf (file, "ADVANCE_PC_PIPE (CPU, %d);\n", ! options.insn_bit_size / 8); ! } ! else ! lf_printf (file, "nia = cia + %d;\n", ! options.insn_bit_size / 8); } } } *************** print_semantic_body (lf *file, *** 237,252 **** lf_printf (file, " {\n"); lf_indent (file, +4); /* FIXME - need to log a conditional failure */ - } - - /* Architecture expects a REG to be zero. Instead of having to - check every read to see if it is refering to that REG just zap it - at the start of every instruction */ - if (options.gen.zero_reg) - { - lf_printf (file, "\n"); - lf_printf (file, "/* Architecture expects REG to be zero */\n"); - lf_printf (file, "GPR_CLEAR(%d);\n", options.gen.zero_reg_nr); } /* generate the code (or at least something */ --- 244,249 ---- Index: gen-support.c =================================================================== RCS file: /cvs/src/src/sim/igen/gen-support.c,v retrieving revision 1.1.1.1 diff -c -p -r1.1.1.1 gen-support.c *** gen-support.c 1999/04/16 01:35:04 1.1.1.1 --- gen-support.c 2000/12/03 00:22:02 *************** print_support_function_name (lf *file, *** 77,83 **** lf_printf (file, "%s%s\n(", options.module.support.prefix.l, function->name); ! if (options.gen.smp) lf_printf (file, "sim_cpu *cpu, %sinstruction_address cia, int MY_INDEX", options.module.support.prefix.l); --- 77,83 ---- lf_printf (file, "%s%s\n(", options.module.support.prefix.l, function->name); ! if (options.gen.smp || options.gen.delay_slot) lf_printf (file, "sim_cpu *cpu, %sinstruction_address cia, int MY_INDEX", options.module.support.prefix.l); *************** gen_support_h (lf *file, *** 111,117 **** insn_table *table) { /* output the definition of `SD_'*/ ! if (options.gen.smp) { lf_printf(file, "#define SD CPU_STATE (cpu)\n"); lf_printf(file, "#define CPU cpu\n"); --- 111,117 ---- insn_table *table) { /* output the definition of `SD_'*/ ! if (options.gen.smp || options.gen.delay_slot) { lf_printf(file, "#define SD CPU_STATE (cpu)\n"); lf_printf(file, "#define CPU cpu\n"); Index: igen.c =================================================================== RCS file: /cvs/src/src/sim/igen/igen.c,v retrieving revision 1.1.1.1 diff -c -p -r1.1.1.1 igen.c *** igen.c 1999/04/16 01:35:04 1.1.1.1 --- igen.c 2000/12/03 00:22:02 *************** print_semantic_function_formal (lf *file *** 65,71 **** nr += lf_printf (file, "%sinstruction_address cia", options.module.global.prefix.l); } ! else if (options.gen.smp) { nr += lf_printf (file, "sim_cpu *cpu,\n"); for (word_nr = 0; word_nr < nr_prefetched_words; word_nr++) --- 65,71 ---- nr += lf_printf (file, "%sinstruction_address cia", options.module.global.prefix.l); } ! else if (options.gen.smp || options.gen.delay_slot) { nr += lf_printf (file, "sim_cpu *cpu,\n"); for (word_nr = 0; word_nr < nr_prefetched_words; word_nr++) *************** print_semantic_function_actual (lf *file *** 104,110 **** } else { ! if (options.gen.smp) nr += lf_printf (file, "cpu"); else nr += lf_printf (file, "sd"); --- 104,110 ---- } else { ! if (options.gen.smp || options.gen.delay_slot) nr += lf_printf (file, "cpu"); else nr += lf_printf (file, "sd"); *************** print_icache_function_formal (lf *file, *** 133,139 **** { int nr = 0; int word_nr; ! if (options.gen.smp) nr += lf_printf (file, "sim_cpu *cpu,\n"); else nr += lf_printf (file, "SIM_DESC sd,\n"); --- 133,139 ---- { int nr = 0; int word_nr; ! if (options.gen.smp || options.gen.delay_slot) nr += lf_printf (file, "sim_cpu *cpu,\n"); else nr += lf_printf (file, "SIM_DESC sd,\n"); *************** print_icache_function_actual (lf *file, *** 153,159 **** { int nr = 0; int word_nr; ! if (options.gen.smp) nr += lf_printf (file, "cpu"); else nr += lf_printf (file, "sd"); --- 153,159 ---- { int nr = 0; int word_nr; ! if (options.gen.smp || options.gen.delay_slot) nr += lf_printf (file, "cpu"); else nr += lf_printf (file, "sd"); *************** main (int argc, *** 1086,1091 **** --- 1086,1092 ---- printf ("\n"); printf ("\t gen-conditional-issue - conditionally issue each instruction\n"); printf ("\t gen-delayed-branch - need both cia and nia passed around\n"); + printf ("\t gen-delay-slot - variant of gen-delayed-branch (in the MIPS style)\n"); printf ("\t gen-direct-access - use #defines to directly access values\n"); printf ("\t gen-zero-r - arch assumes GPR() == 0, keep it that way\n"); printf ("\t gen-icache[= - generate an instruction cracking cache of size \n"); *************** main (int argc, *** 1367,1372 **** --- 1368,1377 ---- { options.gen.delayed_branch = enable_p; options.warning (NULL, "Option delayed-branch replaced by gen-delayed-branch\n"); + } + else if (strcmp (argp, "gen-delay-slot") == 0) + { + options.gen.delay_slot = enable_p; } else if (strcmp (argp, "gen-direct-access") == 0) { Index: igen.h =================================================================== RCS file: /cvs/src/src/sim/igen/igen.h,v retrieving revision 1.1.1.1 diff -c -p -r1.1.1.1 igen.h *** igen.h 1999/04/16 01:35:04 1.1.1.1 --- igen.h 2000/12/03 00:22:02 *************** struct _igen_gen_options { *** 51,56 **** --- 51,57 ---- int conditional_issue; int slot_verification; int delayed_branch; + int delay_slot; /* If zeroing a register, which one? */ int zero_reg; Index: ld-insn.c =================================================================== RCS file: /cvs/src/src/sim/igen/ld-insn.c,v retrieving revision 1.1.1.1 diff -c -p -r1.1.1.1 ld-insn.c *** ld-insn.c 1999/04/16 01:35:05 1.1.1.1 --- ld-insn.c 2000/12/03 00:22:02 *************** typedef enum { *** 618,623 **** --- 618,624 ---- multi_sim_option, format_names_option, gen_delayed_branch, + gen_delay_slot, unknown_option, } option_names; *************** static const name_map option_map[] = { *** 630,635 **** --- 631,637 ---- { "multi-sim", multi_sim_option }, { "format-names", format_names_option }, { "gen-delayed-branch", gen_delayed_branch }, + { "gen-delay-slot", gen_delay_slot }, { NULL, unknown_option }, }; *************** parse_option_record (table *file, *** 723,728 **** --- 725,735 ---- case gen_delayed_branch: { options.gen.delayed_branch = a2i (value); + break; + } + case gen_delay_slot: + { + options.gen.delay_slot = a2i (value); break; } case unknown_option: