diff options
Diffstat (limited to 'tcg/optimize.c')
| -rw-r--r-- | tcg/optimize.c | 167 |
1 files changed, 92 insertions, 75 deletions
diff --git a/tcg/optimize.c b/tcg/optimize.c index da8dffe9cd..1904b396a6 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -39,7 +39,6 @@ typedef enum { TCG_TEMP_UNDEF = 0, TCG_TEMP_CONST, TCG_TEMP_COPY, - TCG_TEMP_HAS_COPY } tcg_temp_state; struct tcg_temp_info { @@ -51,39 +50,19 @@ struct tcg_temp_info { static struct tcg_temp_info temps[TCG_MAX_TEMPS]; -/* Reset TEMP's state to TCG_TEMP_UNDEF. If TEMP was a representative of some - class of equivalent temp's, a new representative should be chosen in this - class. */ -static void reset_temp(TCGArg temp, int nb_temps, int nb_globals) +/* Reset TEMP's state to TCG_TEMP_UNDEF. If TEMP only had one copy, remove + the copy flag from the left temp. */ +static void reset_temp(TCGArg temp) { - int i; - TCGArg new_base = (TCGArg)-1; - if (temps[temp].state == TCG_TEMP_HAS_COPY) { - for (i = temps[temp].next_copy; i != temp; i = temps[i].next_copy) { - if (i >= nb_globals) { - temps[i].state = TCG_TEMP_HAS_COPY; - new_base = i; - break; - } - } - for (i = temps[temp].next_copy; i != temp; i = temps[i].next_copy) { - if (new_base == (TCGArg)-1) { - temps[i].state = TCG_TEMP_UNDEF; - } else { - temps[i].val = new_base; - } + if (temps[temp].state == TCG_TEMP_COPY) { + if (temps[temp].prev_copy == temps[temp].next_copy) { + temps[temps[temp].next_copy].state = TCG_TEMP_UNDEF; + } else { + temps[temps[temp].next_copy].prev_copy = temps[temp].prev_copy; + temps[temps[temp].prev_copy].next_copy = temps[temp].next_copy; } - temps[temps[temp].next_copy].prev_copy = temps[temp].prev_copy; - temps[temps[temp].prev_copy].next_copy = temps[temp].next_copy; - } else if (temps[temp].state == TCG_TEMP_COPY) { - temps[temps[temp].next_copy].prev_copy = temps[temp].prev_copy; - temps[temps[temp].prev_copy].next_copy = temps[temp].next_copy; - new_base = temps[temp].val; } temps[temp].state = TCG_TEMP_UNDEF; - if (new_base != (TCGArg)-1 && temps[new_base].next_copy == new_base) { - temps[new_base].state = TCG_TEMP_UNDEF; - } } static int op_bits(TCGOpcode op) @@ -106,34 +85,83 @@ static TCGOpcode op_to_movi(TCGOpcode op) } } +static TCGArg find_better_copy(TCGContext *s, TCGArg temp) +{ + TCGArg i; + + /* If this is already a global, we can't do better. */ + if (temp < s->nb_globals) { + return temp; + } + + /* Search for a global first. */ + for (i = temps[temp].next_copy ; i != temp ; i = temps[i].next_copy) { + if (i < s->nb_globals) { + return i; + } + } + + /* If it is a temp, search for a temp local. */ + if (!s->temps[temp].temp_local) { + for (i = temps[temp].next_copy ; i != temp ; i = temps[i].next_copy) { + if (s->temps[i].temp_local) { + return i; + } + } + } + + /* Failure to find a better representation, return the same temp. */ + return temp; +} + +static bool temps_are_copies(TCGArg arg1, TCGArg arg2) +{ + TCGArg i; + + if (arg1 == arg2) { + return true; + } + + if (temps[arg1].state != TCG_TEMP_COPY + || temps[arg2].state != TCG_TEMP_COPY) { + return false; + } + + for (i = temps[arg1].next_copy ; i != arg1 ; i = temps[i].next_copy) { + if (i == arg2) { + return true; + } + } + + return false; +} + static void tcg_opt_gen_mov(TCGContext *s, TCGArg *gen_args, TCGArg dst, TCGArg src) { - reset_temp(dst, s->nb_temps, s->nb_globals); - assert(temps[src].state != TCG_TEMP_COPY); - /* Only consider temps with the same type (width) as copies. */ - if (src >= s->nb_globals && s->temps[dst].type == s->temps[src].type) { - assert(temps[src].state != TCG_TEMP_CONST); - if (temps[src].state != TCG_TEMP_HAS_COPY) { - temps[src].state = TCG_TEMP_HAS_COPY; + reset_temp(dst); + assert(temps[src].state != TCG_TEMP_CONST); + + if (s->temps[src].type == s->temps[dst].type) { + if (temps[src].state != TCG_TEMP_COPY) { + temps[src].state = TCG_TEMP_COPY; temps[src].next_copy = src; temps[src].prev_copy = src; } temps[dst].state = TCG_TEMP_COPY; - temps[dst].val = src; temps[dst].next_copy = temps[src].next_copy; temps[dst].prev_copy = src; temps[temps[dst].next_copy].prev_copy = dst; temps[src].next_copy = dst; } + gen_args[0] = dst; gen_args[1] = src; } -static void tcg_opt_gen_movi(TCGArg *gen_args, TCGArg dst, TCGArg val, - int nb_temps, int nb_globals) +static void tcg_opt_gen_movi(TCGArg *gen_args, TCGArg dst, TCGArg val) { - reset_temp(dst, nb_temps, nb_globals); + reset_temp(dst); temps[dst].state = TCG_TEMP_CONST; temps[dst].val = val; gen_args[0] = dst; @@ -324,7 +352,6 @@ static TCGArg do_constant_folding_cond(TCGOpcode op, TCGArg x, tcg_abort(); } - /* Propagate constants and copies, fold constant expressions. */ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, TCGArg *args, TCGOpDef *tcg_op_defs) @@ -338,10 +365,8 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, /* Array VALS has an element for each temp. If this temp holds a constant then its value is kept in VALS' element. - If this temp is a copy of other ones then this equivalence class' - representative is kept in VALS' element. - If this temp is neither copy nor constant then corresponding VALS' - element is unused. */ + If this temp is a copy of other ones then the other copies are + available through the doubly linked circular list. */ nb_temps = s->nb_temps; nb_globals = s->nb_globals; @@ -357,7 +382,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, assert(op != INDEX_op_call); for (i = def->nb_oargs; i < def->nb_oargs + def->nb_iargs; i++) { if (temps[args[i]].state == TCG_TEMP_COPY) { - args[i] = temps[args[i]].val; + args[i] = find_better_copy(s, args[i]); } } } @@ -429,7 +454,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, if (temps[args[1]].state == TCG_TEMP_CONST && temps[args[1]].val == 0) { gen_opc_buf[op_index] = op_to_movi(op); - tcg_opt_gen_movi(gen_args, args[0], 0, nb_temps, nb_globals); + tcg_opt_gen_movi(gen_args, args[0], 0); args += 3; gen_args += 2; continue; @@ -456,9 +481,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, } if (temps[args[2]].state == TCG_TEMP_CONST && temps[args[2]].val == 0) { - if ((temps[args[0]].state == TCG_TEMP_COPY - && temps[args[0]].val == args[1]) - || args[0] == args[1]) { + if (temps_are_copies(args[0], args[1])) { gen_opc_buf[op_index] = INDEX_op_nop; } else { gen_opc_buf[op_index] = op_to_mov(op); @@ -480,7 +503,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, if ((temps[args[2]].state == TCG_TEMP_CONST && temps[args[2]].val == 0)) { gen_opc_buf[op_index] = op_to_movi(op); - tcg_opt_gen_movi(gen_args, args[0], 0, nb_temps, nb_globals); + tcg_opt_gen_movi(gen_args, args[0], 0); args += 3; gen_args += 2; continue; @@ -495,7 +518,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, CASE_OP_32_64(or): CASE_OP_32_64(and): if (args[1] == args[2]) { - if (args[1] == args[0]) { + if (temps_are_copies(args[0], args[1])) { gen_opc_buf[op_index] = INDEX_op_nop; } else { gen_opc_buf[op_index] = op_to_mov(op); @@ -515,9 +538,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, allocator where needed and possible. Also detect copies. */ switch (op) { CASE_OP_32_64(mov): - if ((temps[args[1]].state == TCG_TEMP_COPY - && temps[args[1]].val == args[0]) - || args[0] == args[1]) { + if (temps_are_copies(args[0], args[1])) { args += 2; gen_opc_buf[op_index] = INDEX_op_nop; break; @@ -535,7 +556,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, args[1] = temps[args[1]].val; /* fallthrough */ CASE_OP_32_64(movi): - tcg_opt_gen_movi(gen_args, args[0], args[1], nb_temps, nb_globals); + tcg_opt_gen_movi(gen_args, args[0], args[1]); gen_args += 2; args += 2; break; @@ -550,9 +571,9 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, if (temps[args[1]].state == TCG_TEMP_CONST) { gen_opc_buf[op_index] = op_to_movi(op); tmp = do_constant_folding(op, temps[args[1]].val, 0); - tcg_opt_gen_movi(gen_args, args[0], tmp, nb_temps, nb_globals); + tcg_opt_gen_movi(gen_args, args[0], tmp); } else { - reset_temp(args[0], nb_temps, nb_globals); + reset_temp(args[0]); gen_args[0] = args[0]; gen_args[1] = args[1]; } @@ -580,10 +601,10 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, gen_opc_buf[op_index] = op_to_movi(op); tmp = do_constant_folding(op, temps[args[1]].val, temps[args[2]].val); - tcg_opt_gen_movi(gen_args, args[0], tmp, nb_temps, nb_globals); + tcg_opt_gen_movi(gen_args, args[0], tmp); gen_args += 2; } else { - reset_temp(args[0], nb_temps, nb_globals); + reset_temp(args[0]); gen_args[0] = args[0]; gen_args[1] = args[1]; gen_args[2] = args[2]; @@ -597,10 +618,10 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, gen_opc_buf[op_index] = op_to_movi(op); tmp = do_constant_folding_cond(op, temps[args[1]].val, temps[args[2]].val, args[3]); - tcg_opt_gen_movi(gen_args, args[0], tmp, nb_temps, nb_globals); + tcg_opt_gen_movi(gen_args, args[0], tmp); gen_args += 2; } else { - reset_temp(args[0], nb_temps, nb_globals); + reset_temp(args[0]); gen_args[0] = args[0]; gen_args[1] = args[1]; gen_args[2] = args[2]; @@ -623,7 +644,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, } } else { memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info)); - reset_temp(args[0], nb_temps, nb_globals); + reset_temp(args[0]); gen_args[0] = args[0]; gen_args[1] = args[1]; gen_args[2] = args[2]; @@ -637,23 +658,19 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, && temps[args[2]].state == TCG_TEMP_CONST) { tmp = do_constant_folding_cond(op, temps[args[1]].val, temps[args[2]].val, args[5]); - if (args[0] == args[4-tmp] - || (temps[args[4-tmp]].state == TCG_TEMP_COPY - && temps[args[4-tmp]].val == args[0])) { + if (temps_are_copies(args[0], args[4-tmp])) { gen_opc_buf[op_index] = INDEX_op_nop; } else if (temps[args[4-tmp]].state == TCG_TEMP_CONST) { gen_opc_buf[op_index] = op_to_movi(op); - tcg_opt_gen_movi(gen_args, args[0], temps[args[4-tmp]].val, - nb_temps, nb_globals); + tcg_opt_gen_movi(gen_args, args[0], temps[args[4-tmp]].val); gen_args += 2; } else { gen_opc_buf[op_index] = op_to_mov(op); - tcg_opt_gen_mov(gen_args, args[0], args[4-tmp], - nb_temps, nb_globals); + tcg_opt_gen_mov(s, gen_args, args[0], args[4-tmp]); gen_args += 2; } } else { - reset_temp(args[0], nb_temps, nb_globals); + reset_temp(args[0]); gen_args[0] = args[0]; gen_args[1] = args[1]; gen_args[2] = args[2]; @@ -668,11 +685,11 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, nb_call_args = (args[0] >> 16) + (args[0] & 0xffff); if (!(args[nb_call_args + 1] & (TCG_CALL_CONST | TCG_CALL_PURE))) { for (i = 0; i < nb_globals; i++) { - reset_temp(i, nb_temps, nb_globals); + reset_temp(i); } } for (i = 0; i < (args[0] >> 16); i++) { - reset_temp(args[i + 1], nb_temps, nb_globals); + reset_temp(args[i + 1]); } i = nb_call_args + 3; while (i) { @@ -691,7 +708,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info)); } else { for (i = 0; i < def->nb_oargs; i++) { - reset_temp(args[i], nb_temps, nb_globals); + reset_temp(args[i]); } } for (i = 0; i < def->nb_args; i++) { |