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/* IRA hard register and memory cost calculation for allocnos or pseudos. Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc. Contributed by Vladimir Makarov <vmakarov@redhat.com>. This file is part of GCC. GCC 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 3, or (at your option) any later version. GCC 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 GCC; see the file COPYING3. If not see <http://www.gnu.org/licenses/>. */ #include "config.h" #include "system.h" #include "coretypes.h" #include "tm.h" #include "hard-reg-set.h" #include "rtl.h" #include "expr.h" #include "tm_p.h" #include "flags.h" #include "basic-block.h" #include "regs.h" #include "addresses.h" #include "insn-config.h" #include "recog.h" #include "reload.h" #include "diagnostic-core.h" #include "target.h" #include "params.h" #include "ira-int.h" /* The flags is set up every time when we calculate pseudo register classes through function ira_set_pseudo_classes. */ static bool pseudo_classes_defined_p = false; /* TRUE if we work with allocnos. Otherwise we work with pseudos. */ static bool allocno_p; /* Number of elements in array `costs'. */ static int cost_elements_num; /* The `costs' struct records the cost of using hard registers of each class considered for the calculation and of using memory for each allocno or pseudo. */ struct costs { int mem_cost; /* Costs for register classes start here. We process only some allocno classes. */ int cost[1]; }; #define max_struct_costs_size \ (this_target_ira_int->x_max_struct_costs_size) #define init_cost \ (this_target_ira_int->x_init_cost) #define temp_costs \ (this_target_ira_int->x_temp_costs) #define op_costs \ (this_target_ira_int->x_op_costs) #define this_op_costs \ (this_target_ira_int->x_this_op_costs) /* Costs of each class for each allocno or pseudo. */ static struct costs *costs; /* Accumulated costs of each class for each allocno. */ static struct costs *total_allocno_costs; /* It is the current size of struct costs. */ static int struct_costs_size; /* Return pointer to structure containing costs of allocno or pseudo with given NUM in array ARR. */ #define COSTS(arr, num) \ ((struct costs *) ((char *) (arr) + (num) * struct_costs_size)) /* Return index in COSTS when processing reg with REGNO. */ #define COST_INDEX(regno) (allocno_p \ ? ALLOCNO_NUM (ira_curr_regno_allocno_map[regno]) \ : (int) regno) /* Record register class preferences of each allocno or pseudo. Null value means no preferences. It happens on the 1st iteration of the cost calculation. */ static enum reg_class *pref; /* Allocated buffers for pref. */ static enum reg_class *pref_buffer; /* Record allocno class of each allocno with the same regno. */ static enum reg_class *regno_aclass; /* Record cost gains for not allocating a register with an invariant equivalence. */ static int *regno_equiv_gains; /* Execution frequency of the current insn. */ static int frequency; /* Info about reg classes whose costs are calculated for a pseudo. */ struct cost_classes { /* Number of the cost classes in the subsequent array. */ int num; /* Container of the cost classes. */ enum reg_class classes[N_REG_CLASSES]; /* Map reg class -> index of the reg class in the previous array. -1 if it is not a cost classe. */ int index[N_REG_CLASSES]; /* Map hard regno index of first class in array CLASSES containing the hard regno, -1 otherwise. */ int hard_regno_index[FIRST_PSEUDO_REGISTER]; }; /* Types of pointers to the structure above. */ typedef struct cost_classes *cost_classes_t; typedef const struct cost_classes *const_cost_classes_t; /* Info about cost classes for each pseudo. */ static cost_classes_t *regno_cost_classes; /* Returns hash value for cost classes info V. */ static hashval_t cost_classes_hash (const void *v) { const_cost_classes_t hv = (const_cost_classes_t) v; return iterative_hash (&hv->classes, sizeof (enum reg_class) * hv->num, 0); } /* Compares cost classes info V1 and V2. */ static int cost_classes_eq (const void *v1, const void *v2) { const_cost_classes_t hv1 = (const_cost_classes_t) v1; const_cost_classes_t hv2 = (const_cost_classes_t) v2; return hv1->num == hv2->num && memcmp (hv1->classes, hv2->classes, sizeof (enum reg_class) * hv1->num); } /* Delete cost classes info V from the hash table. */ static void cost_classes_del (void *v) { ira_free (v); } /* Hash table of unique cost classes. */ static htab_t cost_classes_htab; /* Map allocno class -> cost classes for pseudo of given allocno class. */ static cost_classes_t cost_classes_aclass_cache[N_REG_CLASSES]; /* Map mode -> cost classes for pseudo of give mode. */ static cost_classes_t cost_classes_mode_cache[MAX_MACHINE_MODE]; /* Initialize info about the cost classes for each pseudo. */ static void initiate_regno_cost_classes (void) { int size = sizeof (cost_classes_t) * max_reg_num (); regno_cost_classes = (cost_classes_t *) ira_allocate (size); memset (regno_cost_classes, 0, size); memset (cost_classes_aclass_cache, 0, sizeof (cost_classes_t) * N_REG_CLASSES); memset (cost_classes_mode_cache, 0, sizeof (cost_classes_t) * MAX_MACHINE_MODE); cost_classes_htab = htab_create (200, cost_classes_hash, cost_classes_eq, cost_classes_del); } /* Create new cost classes from cost classes FROM and set up members index and hard_regno_index. Return the new classes. The function implements some common code of two functions setup_regno_cost_classes_by_aclass and setup_regno_cost_classes_by_mode. */ static cost_classes_t setup_cost_classes (cost_classes_t from) { cost_classes_t classes_ptr; enum reg_class cl; int i, j, hard_regno; classes_ptr = (cost_classes_t) ira_allocate (sizeof (struct cost_classes)); classes_ptr->num = from->num; for (i = 0; i < N_REG_CLASSES; i++) classes_ptr->index[i] = -1; for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) classes_ptr->hard_regno_index[i] = -1; for (i = 0; i < from->num; i++) { cl = classes_ptr->classes[i] = from->classes[i]; classes_ptr->index[cl] = i; for (j = ira_class_hard_regs_num[cl] - 1; j >= 0; j--) { hard_regno = ira_class_hard_regs[cl][j]; if (classes_ptr->hard_regno_index[hard_regno] < 0) classes_ptr->hard_regno_index[hard_regno] = i; } } return classes_ptr; } /* Setup cost classes for pseudo REGNO whose allocno class is ACLASS. This function is used when we know an initial approximation of allocno class of the pseudo already, e.g. on the second iteration of class cost calculation or after class cost calculation in register-pressure sensitive insn scheduling or register-pressure sensitive loop-invariant motion. */ static void setup_regno_cost_classes_by_aclass (int regno, enum reg_class aclass) { static struct cost_classes classes; cost_classes_t classes_ptr; enum reg_class cl; int i; PTR *slot; HARD_REG_SET temp, temp2; bool exclude_p; if ((classes_ptr = cost_classes_aclass_cache[aclass]) == NULL) { COPY_HARD_REG_SET (temp, reg_class_contents[aclass]); AND_COMPL_HARD_REG_SET (temp, ira_no_alloc_regs); /* We exclude classes from consideration which are subsets of ACLASS only if ACLASS is a pressure class or subset of a pressure class. It means by the definition of pressure classes that cost of moving between susbets of ACLASS is cheaper than load or store. */ for (i = 0; i < ira_pressure_classes_num; i++) { cl = ira_pressure_classes[i]; if (cl == aclass) break; COPY_HARD_REG_SET (temp2, reg_class_contents[cl]); AND_COMPL_HARD_REG_SET (temp2, ira_no_alloc_regs); if (hard_reg_set_subset_p (temp, temp2)) break; } exclude_p = i < ira_pressure_classes_num; classes.num = 0; for (i = 0; i < ira_important_classes_num; i++) { cl = ira_important_classes[i]; if (exclude_p) { /* Exclude no-pressure classes which are subsets of ACLASS. */ COPY_HARD_REG_SET (temp2, reg_class_contents[cl]); AND_COMPL_HARD_REG_SET (temp2, ira_no_alloc_regs); if (! ira_reg_pressure_class_p[cl] && hard_reg_set_subset_p (temp2, temp) && cl != aclass) continue; } classes.classes[classes.num++] = cl; } slot = htab_find_slot (cost_classes_htab, &classes, INSERT); if (*slot == NULL) { classes_ptr = setup_cost_classes (&classes); *slot = classes_ptr; } classes_ptr = cost_classes_aclass_cache[aclass] = (cost_classes_t) *slot; } regno_cost_classes[regno] = classes_ptr; } /* Setup cost classes for pseudo REGNO with MODE. Usage of MODE can decrease number of cost classes for the pseudo, if hard registers of some important classes can not hold a value of MODE. So the pseudo can not get hard register of some important classes and cost calculation for such important classes is only waisting CPU time. */ static void setup_regno_cost_classes_by_mode (int regno, enum machine_mode mode) { static struct cost_classes classes; cost_classes_t classes_ptr; enum reg_class cl; int i; PTR *slot; HARD_REG_SET temp; if ((classes_ptr = cost_classes_mode_cache[mode]) == NULL) { classes.num = 0; for (i = 0; i < ira_important_classes_num; i++) { cl = ira_important_classes[i]; COPY_HARD_REG_SET (temp, ira_prohibited_class_mode_regs[cl][mode]); IOR_HARD_REG_SET (temp, ira_no_alloc_regs); if (hard_reg_set_subset_p (reg_class_contents[cl], temp)) continue; classes.classes[classes.num++] = cl; } slot = htab_find_slot (cost_classes_htab, &classes, INSERT); if (*slot == NULL) { classes_ptr = setup_cost_classes (&classes); *slot = classes_ptr; } else classes_ptr = (cost_classes_t) *slot; cost_classes_mode_cache[mode] = (cost_classes_t) *slot; } regno_cost_classes[regno] = classes_ptr; } /* Finilize info about the cost classes for each pseudo. */ static void finish_regno_cost_classes (void) { ira_free (regno_cost_classes); htab_delete (cost_classes_htab); } /* Compute the cost of loading X into (if TO_P is TRUE) or from (if TO_P is FALSE) a register of class RCLASS in mode MODE. X must not be a pseudo register. */ static int copy_cost (rtx x, enum machine_mode mode, reg_class_t rclass, bool to_p, secondary_reload_info *prev_sri) { secondary_reload_info sri; reg_class_t secondary_class = NO_REGS; /* If X is a SCRATCH, there is actually nothing to move since we are assuming optimal allocation. */ if (GET_CODE (x) == SCRATCH) return 0; /* Get the class we will actually use for a reload. */ rclass = targetm.preferred_reload_class (x, rclass); /* If we need a secondary reload for an intermediate, the cost is that to load the input into the intermediate register, then to copy it. */ sri.prev_sri = prev_sri; sri.extra_cost = 0; secondary_class = targetm.secondary_reload (to_p, x, rclass, mode, &sri); if (secondary_class != NO_REGS) { if (!move_cost[mode]) init_move_cost (mode); return (move_cost[mode][(int) secondary_class][(int) rclass] + sri.extra_cost + copy_cost (x, mode, secondary_class, to_p, &sri)); } /* For memory, use the memory move cost, for (hard) registers, use the cost to move between the register classes, and use 2 for everything else (constants). */ if (MEM_P (x) || rclass == NO_REGS) return sri.extra_cost + ira_memory_move_cost[mode][(int) rclass][to_p != 0]; else if (REG_P (x)) { if (!move_cost[mode]) init_move_cost (mode); return (sri.extra_cost + move_cost[mode][REGNO_REG_CLASS (REGNO (x))][(int) rclass]); } else /* If this is a constant, we may eventually want to call rtx_cost here. */ return sri.extra_cost + COSTS_N_INSNS (1); } /* Record the cost of using memory or hard registers of various classes for the operands in INSN. N_ALTS is the number of alternatives. N_OPS is the number of operands. OPS is an array of the operands. MODES are the modes of the operands, in case any are VOIDmode. CONSTRAINTS are the constraints to use for the operands. This array is modified by this procedure. This procedure works alternative by alternative. For each alternative we assume that we will be able to allocate all allocnos to their ideal register class and calculate the cost of using that alternative. Then we compute, for each operand that is a pseudo-register, the cost of having the allocno allocated to each register class and using it in that alternative. To this cost is added the cost of the alternative. The cost of each class for this insn is its lowest cost among all the alternatives. */ static void record_reg_classes (int n_alts, int n_ops, rtx *ops, enum machine_mode *modes, const char **constraints, rtx insn, enum reg_class *pref) { int alt; int i, j, k; rtx set; int insn_allows_mem[MAX_RECOG_OPERANDS]; for (i = 0; i < n_ops; i++) insn_allows_mem[i] = 0; /* Process each alternative, each time minimizing an operand's cost with the cost for each operand in that alternative. */ for (alt = 0; alt < n_alts; alt++) { enum reg_class classes[MAX_RECOG_OPERANDS]; int allows_mem[MAX_RECOG_OPERANDS]; enum reg_class rclass; int alt_fail = 0; int alt_cost = 0, op_cost_add; if (!recog_data.alternative_enabled_p[alt]) { for (i = 0; i < recog_data.n_operands; i++) constraints[i] = skip_alternative (constraints[i]); continue; } for (i = 0; i < n_ops; i++) { unsigned char c; const char *p = constraints[i]; rtx op = ops[i]; enum machine_mode mode = modes[i]; int allows_addr = 0; int win = 0; /* Initially show we know nothing about the register class. */ classes[i] = NO_REGS; allows_mem[i] = 0; /* If this operand has no constraints at all, we can conclude nothing about it since anything is valid. */ if (*p == 0) { if (REG_P (op) && REGNO (op) >= FIRST_PSEUDO_REGISTER) memset (this_op_costs[i], 0, struct_costs_size); continue; } /* If this alternative is only relevant when this operand matches a previous operand, we do different things depending on whether this operand is a allocno-reg or not. We must process any modifiers for the operand before we can make this test. */ while (*p == '%' || *p == '=' || *p == '+' || *p == '&') p++; if (p[0] >= '0' && p[0] <= '0' + i && (p[1] == ',' || p[1] == 0)) { /* Copy class and whether memory is allowed from the matching alternative. Then perform any needed cost computations and/or adjustments. */ j = p[0] - '0'; classes[i] = classes[j]; allows_mem[i] = allows_mem[j]; if (allows_mem[i]) insn_allows_mem[i] = 1; if (! REG_P (op) || REGNO (op) < FIRST_PSEUDO_REGISTER) { /* If this matches the other operand, we have no added cost and we win. */ if (rtx_equal_p (ops[j], op)) win = 1; /* If we can put the other operand into a register, add to the cost of this alternative the cost to copy this operand to the register used for the other operand. */ else if (classes[j] != NO_REGS) { alt_cost += copy_cost (op, mode, classes[j], 1, NULL); win = 1; } } else if (! REG_P (ops[j]) || REGNO (ops[j]) < FIRST_PSEUDO_REGISTER) { /* This op is an allocno but the one it matches is not. */ /* If we can't put the other operand into a register, this alternative can't be used. */ if (classes[j] == NO_REGS) alt_fail = 1; /* Otherwise, add to the cost of this alternative the cost to copy the other operand to the hard register used for this operand. */ else alt_cost += copy_cost (ops[j], mode, classes[j], 1, NULL); } else { /* The costs of this operand are not the same as the other operand since move costs are not symmetric. Moreover, if we cannot tie them, this alternative needs to do a copy, which is one insn. */ struct costs *pp = this_op_costs[i]; int *pp_costs = pp->cost; cost_classes_t cost_classes_ptr = regno_cost_classes[REGNO (op)]; enum reg_class *cost_classes = cost_classes_ptr->classes; bool in_p = recog_data.operand_type[i] != OP_OUT; bool out_p = recog_data.operand_type[i] != OP_IN; enum reg_class op_class = classes[i]; move_table *move_in_cost, *move_out_cost; ira_init_register_move_cost_if_necessary (mode); if (! in_p) { ira_assert (out_p); move_out_cost = ira_may_move_out_cost[mode]; for (k = cost_classes_ptr->num - 1; k >= 0; k--) { rclass = cost_classes[k]; pp_costs[k] = move_out_cost[op_class][rclass] * frequency; } } else if (! out_p) { ira_assert (in_p); move_in_cost = ira_may_move_in_cost[mode]; for (k = cost_classes_ptr->num - 1; k >= 0; k--) { rclass = cost_classes[k]; pp_costs[k] = move_in_cost[rclass][op_class] * frequency; } } else { move_in_cost = ira_may_move_in_cost[mode]; move_out_cost = ira_may_move_out_cost[mode]; for (k = cost_classes_ptr->num - 1; k >= 0; k--) { rclass = cost_classes[k]; pp_costs[k] = ((move_in_cost[rclass][op_class] + move_out_cost[op_class][rclass]) * frequency); } } /* If the alternative actually allows memory, make things a bit cheaper since we won't need an extra insn to load it. */ pp->mem_cost = ((out_p ? ira_memory_move_cost[mode][op_class][0] : 0) + (in_p ? ira_memory_move_cost[mode][op_class][1] : 0) - allows_mem[i]) * frequency; /* If we have assigned a class to this allocno in our first pass, add a cost to this alternative corresponding to what we would add if this allocno were not in the appropriate class. */ if (pref) { enum reg_class pref_class = pref[COST_INDEX (REGNO (op))]; if (pref_class == NO_REGS) alt_cost += ((out_p ? ira_memory_move_cost[mode][op_class][0] : 0) + (in_p ? ira_memory_move_cost[mode][op_class][1] : 0)); else if (ira_reg_class_intersect [pref_class][op_class] == NO_REGS) alt_cost += ira_register_move_cost[mode][pref_class][op_class]; } if (REGNO (ops[i]) != REGNO (ops[j]) && ! find_reg_note (insn, REG_DEAD, op)) alt_cost += 2; /* This is in place of ordinary cost computation for this operand, so skip to the end of the alternative (should be just one character). */ while (*p && *p++ != ',') ; constraints[i] = p; continue; } } /* Scan all the constraint letters. See if the operand matches any of the constraints. Collect the valid register classes and see if this operand accepts memory. */ while ((c = *p)) { switch (c) { case ',': break; case '*': /* Ignore the next letter for this pass. */ c = *++p; break; case '?': alt_cost += 2; case '!': case '#': case '&': case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': break; case 'p': allows_addr = 1; win = address_operand (op, GET_MODE (op)); /* We know this operand is an address, so we want it to be allocated to a register that can be the base of an address, i.e. BASE_REG_CLASS. */ classes[i] = ira_reg_class_subunion[classes[i]] [base_reg_class (VOIDmode, ADDR_SPACE_GENERIC, ADDRESS, SCRATCH)]; break; case 'm': case 'o': case 'V': /* It doesn't seem worth distinguishing between offsettable and non-offsettable addresses here. */ insn_allows_mem[i] = allows_mem[i] = 1; if (MEM_P (op)) win = 1; break; case '<': if (MEM_P (op) && (GET_CODE (XEXP (op, 0)) == PRE_DEC || GET_CODE (XEXP (op, 0)) == POST_DEC)) win = 1; break; case '>': if (MEM_P (op) && (GET_CODE (XEXP (op, 0)) == PRE_INC || GET_CODE (XEXP (op, 0)) == POST_INC)) win = 1; break; case 'E': case 'F': if (GET_CODE (op) == CONST_DOUBLE || (GET_CODE (op) == CONST_VECTOR && (GET_MODE_CLASS (GET_MODE (op)) == MODE_VECTOR_FLOAT))) win = 1; break; case 'G': case 'H': if (GET_CODE (op) == CONST_DOUBLE && CONST_DOUBLE_OK_FOR_CONSTRAINT_P (op, c, p)) win = 1; break; case 's': if (CONST_INT_P (op) || (GET_CODE (op) == CONST_DOUBLE && GET_MODE (op) == VOIDmode)) break; case 'i': if (CONSTANT_P (op) && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (op))) win = 1; break; case 'n': if (CONST_INT_P (op) || (GET_CODE (op) == CONST_DOUBLE && GET_MODE (op) == VOIDmode)) win = 1; break; case 'I': case 'J': case 'K': case 'L': case 'M': case 'N': case 'O': case 'P': if (CONST_INT_P (op) && CONST_OK_FOR_CONSTRAINT_P (INTVAL (op), c, p)) win = 1; break; case 'X': win = 1; break; case 'g': if (MEM_P (op) || (CONSTANT_P (op) && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (op)))) win = 1; insn_allows_mem[i] = allows_mem[i] = 1; case 'r': classes[i] = ira_reg_class_subunion[classes[i]][GENERAL_REGS]; break; default: if (REG_CLASS_FROM_CONSTRAINT (c, p) != NO_REGS) classes[i] = ira_reg_class_subunion[classes[i]] [REG_CLASS_FROM_CONSTRAINT (c, p)]; #ifdef EXTRA_CONSTRAINT_STR else if (EXTRA_CONSTRAINT_STR (op, c, p)) win = 1; if (EXTRA_MEMORY_CONSTRAINT (c, p)) { /* Every MEM can be reloaded to fit. */ insn_allows_mem[i] = allows_mem[i] = 1; if (MEM_P (op)) win = 1; } if (EXTRA_ADDRESS_CONSTRAINT (c, p)) { /* Every address can be reloaded to fit. */ allows_addr = 1; if (address_operand (op, GET_MODE (op))) win = 1; /* We know this operand is an address, so we want it to be allocated to a hard register that can be the base of an address, i.e. BASE_REG_CLASS. */ classes[i] = ira_reg_class_subunion[classes[i]] [base_reg_class (VOIDmode, ADDR_SPACE_GENERIC, ADDRESS, SCRATCH)]; } #endif break; } p += CONSTRAINT_LEN (c, p); if (c == ',') break; } constraints[i] = p; /* How we account for this operand now depends on whether it is a pseudo register or not. If it is, we first check if any register classes are valid. If not, we ignore this alternative, since we want to assume that all allocnos get allocated for register preferencing. If some register class is valid, compute the costs of moving the allocno into that class. */ if (REG_P (op) && REGNO (op) >= FIRST_PSEUDO_REGISTER) { if (classes[i] == NO_REGS) { /* We must always fail if the operand is a REG, but we did not find a suitable class. Otherwise we may perform an uninitialized read from this_op_costs after the `continue' statement below. */ alt_fail = 1; } else { unsigned int regno = REGNO (op); struct costs *pp = this_op_costs[i]; int *pp_costs = pp->cost; cost_classes_t cost_classes_ptr = regno_cost_classes[regno]; enum reg_class *cost_classes = cost_classes_ptr->classes; bool in_p = recog_data.operand_type[i] != OP_OUT; bool out_p = recog_data.operand_type[i] != OP_IN; enum reg_class op_class = classes[i]; move_table *move_in_cost, *move_out_cost; ira_init_register_move_cost_if_necessary (mode); if (! in_p) { ira_assert (out_p); move_out_cost = ira_may_move_out_cost[mode]; for (k = cost_classes_ptr->num - 1; k >= 0; k--) { rclass = cost_classes[k]; pp_costs[k] = move_out_cost[op_class][rclass] * frequency; } } else if (! out_p) { ira_assert (in_p); move_in_cost = ira_may_move_in_cost[mode]; for (k = cost_classes_ptr->num - 1; k >= 0; k--) { rclass = cost_classes[k]; pp_costs[k] = move_in_cost[rclass][op_class] * frequency; } } else { move_in_cost = ira_may_move_in_cost[mode]; move_out_cost = ira_may_move_out_cost[mode]; for (k = cost_classes_ptr->num - 1; k >= 0; k--) { rclass = cost_classes[k]; pp_costs[k] = ((move_in_cost[rclass][op_class] + move_out_cost[op_class][rclass]) * frequency); } } /* If the alternative actually allows memory, make things a bit cheaper since we won't need an extra insn to load it. */ pp->mem_cost = ((out_p ? ira_memory_move_cost[mode][op_class][0] : 0) + (in_p ? ira_memory_move_cost[mode][op_class][1] : 0) - allows_mem[i]) * frequency; /* If we have assigned a class to this allocno in our first pass, add a cost to this alternative corresponding to what we would add if this allocno were not in the appropriate class. */ if (pref) { enum reg_class pref_class = pref[COST_INDEX (REGNO (op))]; if (pref_class == NO_REGS) alt_cost += ((out_p ? ira_memory_move_cost[mode][op_class][0] : 0) + (in_p ? ira_memory_move_cost[mode][op_class][1] : 0)); else if (ira_reg_class_intersect[pref_class][op_class] == NO_REGS) alt_cost += ira_register_move_cost[mode][pref_class][op_class]; } } } /* Otherwise, if this alternative wins, either because we have already determined that or if we have a hard register of the proper class, there is no cost for this alternative. */ else if (win || (REG_P (op) && reg_fits_class_p (op, classes[i], 0, GET_MODE (op)))) ; /* If registers are valid, the cost of this alternative includes copying the object to and/or from a register. */ else if (classes[i] != NO_REGS) { if (recog_data.operand_type[i] != OP_OUT) alt_cost += copy_cost (op, mode, classes[i], 1, NULL); if (recog_data.operand_type[i] != OP_IN) alt_cost += copy_cost (op, mode, classes[i], 0, NULL); } /* The only other way this alternative can be used is if this is a constant that could be placed into memory. */ else if (CONSTANT_P (op) && (allows_addr || allows_mem[i])) alt_cost += ira_memory_move_cost[mode][classes[i]][1]; else alt_fail = 1; } if (alt_fail) continue; op_cost_add = alt_cost * frequency; /* Finally, update the costs with the information we've calculated about this alternative. */ for (i = 0; i < n_ops; i++) if (REG_P (ops[i]) && REGNO (ops[i]) >= FIRST_PSEUDO_REGISTER) { struct costs *pp = op_costs[i], *qq = this_op_costs[i]; int *pp_costs = pp->cost, *qq_costs = qq->cost; int scale = 1 + (recog_data.operand_type[i] == OP_INOUT); cost_classes_t cost_classes_ptr = regno_cost_classes[REGNO (ops[i])]; pp->mem_cost = MIN (pp->mem_cost, (qq->mem_cost + op_cost_add) * scale); for (k = cost_classes_ptr->num - 1; k >= 0; k--) pp_costs[k] = MIN (pp_costs[k], (qq_costs[k] + op_cost_add) * scale); } } if (allocno_p) for (i = 0; i < n_ops; i++) { ira_allocno_t a; rtx op = ops[i]; if (! REG_P (op) || REGNO (op) < FIRST_PSEUDO_REGISTER) continue; a = ira_curr_regno_allocno_map [REGNO (op)]; if (! ALLOCNO_BAD_SPILL_P (a) && insn_allows_mem[i] == 0) ALLOCNO_BAD_SPILL_P (a) = true; } /* If this insn is a single set copying operand 1 to operand 0 and one operand is an allocno with the other a hard reg or an allocno that prefers a hard register that is in its own register class then we may want to adjust the cost of that register class to -1. Avoid the adjustment if the source does not die to avoid stressing of register allocator by preferrencing two colliding registers into single class. Also avoid the adjustment if a copy between hard registers of the class is expensive (ten times the cost of a default copy is considered arbitrarily expensive). This avoids losing when the preferred class is very expensive as the source of a copy instruction. */ if ((set = single_set (insn)) != 0 && ops[0] == SET_DEST (set) && ops[1] == SET_SRC (set) && REG_P (ops[0]) && REG_P (ops[1]) && find_regno_note (insn, REG_DEAD, REGNO (ops[1]))) for (i = 0; i <= 1; i++) if (REGNO (ops[i]) >= FIRST_PSEUDO_REGISTER && REGNO (ops[!i]) < FIRST_PSEUDO_REGISTER) { unsigned int regno = REGNO (ops[i]); unsigned int other_regno = REGNO (ops[!i]); enum machine_mode mode = GET_MODE (ops[!i]); cost_classes_t cost_classes_ptr = regno_cost_classes[regno]; enum reg_class *cost_classes = cost_classes_ptr->classes; reg_class_t rclass; int nr; for (k = cost_classes_ptr->num - 1; k >= 0; k--) { rclass = cost_classes[k]; if (TEST_HARD_REG_BIT (reg_class_contents[rclass], other_regno) && (reg_class_size[(int) rclass] == ira_reg_class_max_nregs [(int) rclass][(int) mode])) { if (reg_class_size[rclass] == 1) op_costs[i]->cost[k] = -frequency; else { for (nr = 0; nr < hard_regno_nregs[other_regno][mode]; nr++) if (! TEST_HARD_REG_BIT (reg_class_contents[rclass], other_regno + nr)) break; if (nr == hard_regno_nregs[other_regno][mode]) op_costs[i]->cost[k] = -frequency; } } } } } /* Wrapper around REGNO_OK_FOR_INDEX_P, to allow pseudo registers. */ static inline bool ok_for_index_p_nonstrict (rtx reg) { unsigned regno = REGNO (reg); return regno >= FIRST_PSEUDO_REGISTER || REGNO_OK_FOR_INDEX_P (regno); } /* A version of regno_ok_for_base_p for use here, when all pseudo-registers should count as OK. Arguments as for regno_ok_for_base_p. */ static inline bool ok_for_base_p_nonstrict (rtx reg, enum machine_mode mode, addr_space_t as, enum rtx_code outer_code, enum rtx_code index_code) { unsigned regno = REGNO (reg); if (regno >= FIRST_PSEUDO_REGISTER) return true; return ok_for_base_p_1 (regno, mode, as, outer_code, index_code); } /* Record the pseudo registers we must reload into hard registers in a subexpression of a memory address, X. If CONTEXT is 0, we are looking at the base part of an address, otherwise we are looking at the index part. MODE and AS are the mode and address space of the memory reference; OUTER_CODE and INDEX_CODE give the context that the rtx appears in. These four arguments are passed down to base_reg_class. SCALE is twice the amount to multiply the cost by (it is twice so we can represent half-cost adjustments). */ static void record_address_regs (enum machine_mode mode, addr_space_t as, rtx x, int context, enum rtx_code outer_code, enum rtx_code index_code, int scale) { enum rtx_code code = GET_CODE (x); enum reg_class rclass; if (context == 1) rclass = INDEX_REG_CLASS; else rclass = base_reg_class (mode, as, outer_code, index_code); switch (code) { case CONST_INT: case CONST: case CC0: case PC: case SYMBOL_REF: case LABEL_REF: return; case PLUS: /* When we have an address that is a sum, we must determine whether registers are "base" or "index" regs. If there is a sum of two registers, we must choose one to be the "base". Luckily, we can use the REG_POINTER to make a good choice most of the time. We only need to do this on machines that can have two registers in an address and where the base and index register classes are different. ??? This code used to set REGNO_POINTER_FLAG in some cases, but that seems bogus since it should only be set when we are sure the register is being used as a pointer. */ { rtx arg0 = XEXP (x, 0); rtx arg1 = XEXP (x, 1); enum rtx_code code0 = GET_CODE (arg0); enum rtx_code code1 = GET_CODE (arg1); /* Look inside subregs. */ if (code0 == SUBREG) arg0 = SUBREG_REG (arg0), code0 = GET_CODE (arg0); if (code1 == SUBREG) arg1 = SUBREG_REG (arg1), code1 = GET_CODE (arg1); /* If this machine only allows one register per address, it must be in the first operand. */ if (MAX_REGS_PER_ADDRESS == 1) record_address_regs (mode, as, arg0, 0, PLUS, code1, scale); /* If index and base registers are the same on this machine, just record registers in any non-constant operands. We assume here, as well as in the tests below, that all addresses are in canonical form. */ else if (INDEX_REG_CLASS == base_reg_class (VOIDmode, as, PLUS, SCRATCH)) { record_address_regs (mode, as, arg0, context, PLUS, code1, scale); if (! CONSTANT_P (arg1)) record_address_regs (mode, as, arg1, context, PLUS, code0, scale); } /* If the second operand is a constant integer, it doesn't change what class the first operand must be. */ else if (code1 == CONST_INT || code1 == CONST_DOUBLE) record_address_regs (mode, as, arg0, context, PLUS, code1, scale); /* If the second operand is a symbolic constant, the first operand must be an index register. */ else if (code1 == SYMBOL_REF || code1 == CONST || code1 == LABEL_REF) record_address_regs (mode, as, arg0, 1, PLUS, code1, scale); /* If both operands are registers but one is already a hard register of index or reg-base class, give the other the class that the hard register is not. */ else if (code0 == REG && code1 == REG && REGNO (arg0) < FIRST_PSEUDO_REGISTER && (ok_for_base_p_nonstrict (arg0, mode, as, PLUS, REG) || ok_for_index_p_nonstrict (arg0))) record_address_regs (mode, as, arg1, ok_for_base_p_nonstrict (arg0, mode, as, PLUS, REG) ? 1 : 0, PLUS, REG, scale); else if (code0 == REG && code1 == REG && REGNO (arg1) < FIRST_PSEUDO_REGISTER && (ok_for_base_p_nonstrict (arg1, mode, as, PLUS, REG) || ok_for_index_p_nonstrict (arg1))) record_address_regs (mode, as, arg0, ok_for_base_p_nonstrict (arg1, mode, as, PLUS, REG) ? 1 : 0, PLUS, REG, scale); /* If one operand is known to be a pointer, it must be the base with the other operand the index. Likewise if the other operand is a MULT. */ else if ((code0 == REG && REG_POINTER (arg0)) || code1 == MULT) { record_address_regs (mode, as, arg0, 0, PLUS, code1, scale); record_address_regs (mode, as, arg1, 1, PLUS, code0, scale); } else if ((code1 == REG && REG_POINTER (arg1)) || code0 == MULT) { record_address_regs (mode, as, arg0, 1, PLUS, code1, scale); record_address_regs (mode, as, arg1, 0, PLUS, code0, scale); } /* Otherwise, count equal chances that each might be a base or index register. This case should be rare. */ else { record_address_regs (mode, as, arg0, 0, PLUS, code1, scale / 2); record_address_regs (mode, as, arg0, 1, PLUS, code1, scale / 2); record_address_regs (mode, as, arg1, 0, PLUS, code0, scale / 2); record_address_regs (mode, as, arg1, 1, PLUS, code0, scale / 2); } } break; /* Double the importance of an allocno that is incremented or decremented, since it would take two extra insns if it ends up in the wrong place. */ case POST_MODIFY: case PRE_MODIFY: record_address_regs (mode, as, XEXP (x, 0), 0, code, GET_CODE (XEXP (XEXP (x, 1), 1)), 2 * scale); if (REG_P (XEXP (XEXP (x, 1), 1))) record_address_regs (mode, as, XEXP (XEXP (x, 1), 1), 1, code, REG, 2 * scale); break; case POST_INC: case PRE_INC: case POST_DEC: case PRE_DEC: /* Double the importance of an allocno that is incremented or decremented, since it would take two extra insns if it ends up in the wrong place. */ record_address_regs (mode, as, XEXP (x, 0), 0, code, SCRATCH, 2 * scale); break; case REG: { struct costs *pp; int *pp_costs; enum reg_class i; int k, regno, add_cost; cost_classes_t cost_classes_ptr; enum reg_class *cost_classes; move_table *move_in_cost; if (REGNO (x) < FIRST_PSEUDO_REGISTER) break; regno = REGNO (x); if (allocno_p) ALLOCNO_BAD_SPILL_P (ira_curr_regno_allocno_map[regno]) = true; pp = COSTS (costs, COST_INDEX (regno)); add_cost = (ira_memory_move_cost[Pmode][rclass][1] * scale) / 2; if (INT_MAX - add_cost < pp->mem_cost) pp->mem_cost = INT_MAX; else pp->mem_cost += add_cost; cost_classes_ptr = regno_cost_classes[regno]; cost_classes = cost_classes_ptr->classes; pp_costs = pp->cost; ira_init_register_move_cost_if_necessary (Pmode); move_in_cost = ira_may_move_in_cost[Pmode]; for (k = cost_classes_ptr->num - 1; k >= 0; k--) { i = cost_classes[k]; add_cost = (move_in_cost[i][rclass] * scale) / 2; if (INT_MAX - add_cost < pp_costs[k]) pp_costs[k] = INT_MAX; else pp_costs[k] += add_cost; } } break; default: { const char *fmt = GET_RTX_FORMAT (code); int i; for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) if (fmt[i] == 'e') record_address_regs (mode, as, XEXP (x, i), context, code, SCRATCH, scale); } } } /* Calculate the costs of insn operands. */ static void record_operand_costs (rtx insn, enum reg_class *pref) { const char *constraints[MAX_RECOG_OPERANDS]; enum machine_mode modes[MAX_RECOG_OPERANDS]; int i; for (i = 0; i < recog_data.n_operands; i++) { constraints[i] = recog_data.constraints[i]; modes[i] = recog_data.operand_mode[i]; } /* If we get here, we are set up to record the costs of all the operands for this insn. Start by initializing the costs. Then handle any address registers. Finally record the desired classes for any allocnos, doing it twice if some pair of operands are commutative. */ for (i = 0; i < recog_data.n_operands; i++) { memcpy (op_costs[i], init_cost, struct_costs_size); if (GET_CODE (recog_data.operand[i]) == SUBREG) recog_data.operand[i] = SUBREG_REG (recog_data.operand[i]); if (MEM_P (recog_data.operand[i])) record_address_regs (GET_MODE (recog_data.operand[i]), MEM_ADDR_SPACE (recog_data.operand[i]), XEXP (recog_data.operand[i], 0), 0, MEM, SCRATCH, frequency * 2); else if (constraints[i][0] == 'p' || EXTRA_ADDRESS_CONSTRAINT (constraints[i][0], constraints[i])) record_address_regs (VOIDmode, ADDR_SPACE_GENERIC, recog_data.operand[i], 0, ADDRESS, SCRATCH, frequency * 2); } /* Check for commutative in a separate loop so everything will have been initialized. We must do this even if one operand is a constant--see addsi3 in m68k.md. */ for (i = 0; i < (int) recog_data.n_operands - 1; i++) if (constraints[i][0] == '%') { const char *xconstraints[MAX_RECOG_OPERANDS]; int j; /* Handle commutative operands by swapping the constraints. We assume the modes are the same. */ for (j = 0; j < recog_data.n_operands; j++) xconstraints[j] = constraints[j]; xconstraints[i] = constraints[i+1]; xconstraints[i+1] = constraints[i]; record_reg_classes (recog_data.n_alternatives, recog_data.n_operands, recog_data.operand, modes, xconstraints, insn, pref); } record_reg_classes (recog_data.n_alternatives, recog_data.n_operands, recog_data.operand, modes, constraints, insn, pref); } /* Process one insn INSN. Scan it and record each time it would save code to put a certain allocnos in a certain class. Return the last insn processed, so that the scan can be continued from there. */ static rtx scan_one_insn (rtx insn) { enum rtx_code pat_code; rtx set, note; int i, k; bool counted_mem; if (!NONDEBUG_INSN_P (insn)) return insn; pat_code = GET_CODE (PATTERN (insn)); if (pat_code == USE || pat_code == CLOBBER || pat_code == ASM_INPUT || pat_code == ADDR_VEC || pat_code == ADDR_DIFF_VEC) return insn; counted_mem = false; set = single_set (insn); extract_insn (insn); /* If this insn loads a parameter from its stack slot, then it represents a savings, rather than a cost, if the parameter is stored in memory. Record this fact. Similarly if we're loading other constants from memory (constant pool, TOC references, small data areas, etc) and this is the only assignment to the destination pseudo. Don't do this if SET_SRC (set) isn't a general operand, if it is a memory requiring special instructions to load it, decreasing mem_cost might result in it being loaded using the specialized instruction into a register, then stored into stack and loaded again from the stack. See PR52208. */ if (set != 0 && REG_P (SET_DEST (set)) && MEM_P (SET_SRC (set)) && (note = find_reg_note (insn, REG_EQUIV, NULL_RTX)) != NULL_RTX && ((MEM_P (XEXP (note, 0))) || (CONSTANT_P (XEXP (note, 0)) && targetm.legitimate_constant_p (GET_MODE (SET_DEST (set)), XEXP (note, 0)) && REG_N_SETS (REGNO (SET_DEST (set))) == 1)) && general_operand (SET_SRC (set), GET_MODE (SET_SRC (set)))) { enum reg_class cl = GENERAL_REGS; rtx reg = SET_DEST (set); int num = COST_INDEX (REGNO (reg)); COSTS (costs, num)->mem_cost -= ira_memory_move_cost[GET_MODE (reg)][cl][1] * frequency; record_address_regs (GET_MODE (SET_SRC (set)), MEM_ADDR_SPACE (SET_SRC (set)), XEXP (SET_SRC (set), 0), 0, MEM, SCRATCH, frequency * 2); counted_mem = true; } record_operand_costs (insn, pref); /* Now add the cost for each operand to the total costs for its allocno. */ for (i = 0; i < recog_data.n_operands; i++) if (REG_P (recog_data.operand[i]) && REGNO (recog_data.operand[i]) >= FIRST_PSEUDO_REGISTER) { int regno = REGNO (recog_data.operand[i]); struct costs *p = COSTS (costs, COST_INDEX (regno)); struct costs *q = op_costs[i]; int *p_costs = p->cost, *q_costs = q->cost; cost_classes_t cost_classes_ptr = regno_cost_classes[regno]; int add_cost; /* If the already accounted for the memory "cost" above, don't do so again. */ if (!counted_mem) { add_cost = q->mem_cost; if (add_cost > 0 && INT_MAX - add_cost < p->mem_cost) p->mem_cost = INT_MAX; else p->mem_cost += add_cost; } for (k = cost_classes_ptr->num - 1; k >= 0; k--) { add_cost = q_costs[k]; if (add_cost > 0 && INT_MAX - add_cost < p_costs[k]) p_costs[k] = INT_MAX; else p_costs[k] += add_cost; } } return insn; } /* Print allocnos costs to file F. */ static void print_allocno_costs (FILE *f) { int k; ira_allocno_t a; ira_allocno_iterator ai; ira_assert (allocno_p); fprintf (f, "\n"); FOR_EACH_ALLOCNO (a, ai) { int i, rclass; basic_block bb; int regno = ALLOCNO_REGNO (a); cost_classes_t cost_classes_ptr = regno_cost_classes[regno]; enum reg_class *cost_classes = cost_classes_ptr->classes; i = ALLOCNO_NUM (a); fprintf (f, " a%d(r%d,", i, regno); if ((bb = ALLOCNO_LOOP_TREE_NODE (a)->bb) != NULL) fprintf (f, "b%d", bb->index); else fprintf (f, "l%d", ALLOCNO_LOOP_TREE_NODE (a)->loop_num); fprintf (f, ") costs:"); for (k = 0; k < cost_classes_ptr->num; k++) { rclass = cost_classes[k]; if (contains_reg_of_mode[rclass][PSEUDO_REGNO_MODE (regno)] #ifdef CANNOT_CHANGE_MODE_CLASS && ! invalid_mode_change_p (regno, (enum reg_class) rclass) #endif ) { fprintf (f, " %s:%d", reg_class_names[rclass], COSTS (costs, i)->cost[k]); if (flag_ira_region == IRA_REGION_ALL || flag_ira_region == IRA_REGION_MIXED) fprintf (f, ",%d", COSTS (total_allocno_costs, i)->cost[k]); } } fprintf (f, " MEM:%i", COSTS (costs, i)->mem_cost); if (flag_ira_region == IRA_REGION_ALL || flag_ira_region == IRA_REGION_MIXED) fprintf (f, ",%d", COSTS (total_allocno_costs, i)->mem_cost); fprintf (f, "\n"); } } /* Print pseudo costs to file F. */ static void print_pseudo_costs (FILE *f) { int regno, k; int rclass; cost_classes_t cost_classes_ptr; enum reg_class *cost_classes; ira_assert (! allocno_p); fprintf (f, "\n"); for (regno = max_reg_num () - 1; regno >= FIRST_PSEUDO_REGISTER; regno--) { if (REG_N_REFS (regno) <= 0) continue; cost_classes_ptr = regno_cost_classes[regno]; cost_classes = cost_classes_ptr->classes; fprintf (f, " r%d costs:", regno); for (k = 0; k < cost_classes_ptr->num; k++) { rclass = cost_classes[k]; if (contains_reg_of_mode[rclass][PSEUDO_REGNO_MODE (regno)] #ifdef CANNOT_CHANGE_MODE_CLASS && ! invalid_mode_change_p (regno, (enum reg_class) rclass) #endif ) fprintf (f, " %s:%d", reg_class_names[rclass], COSTS (costs, regno)->cost[k]); } fprintf (f, " MEM:%i\n", COSTS (costs, regno)->mem_cost); } } /* Traverse the BB represented by LOOP_TREE_NODE to update the allocno costs. */ static void process_bb_for_costs (basic_block bb) { rtx insn; frequency = REG_FREQ_FROM_BB (bb); if (frequency == 0) frequency = 1; FOR_BB_INSNS (bb, insn) insn = scan_one_insn (insn); } /* Traverse the BB represented by LOOP_TREE_NODE to update the allocno costs. */ static void process_bb_node_for_costs (ira_loop_tree_node_t loop_tree_node) { basic_block bb; bb = loop_tree_node->bb; if (bb != NULL) process_bb_for_costs (bb); } /* Find costs of register classes and memory for allocnos or pseudos and their best costs. Set up preferred, alternative and allocno classes for pseudos. */ static void find_costs_and_classes (FILE *dump_file) { int i, k, start, max_cost_classes_num; int pass; basic_block bb; enum reg_class *regno_best_class; init_recog (); regno_best_class = (enum reg_class *) ira_allocate (max_reg_num () * sizeof (enum reg_class)); for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--) regno_best_class[i] = NO_REGS; if (!resize_reg_info () && allocno_p && pseudo_classes_defined_p && flag_expensive_optimizations) { ira_allocno_t a; ira_allocno_iterator ai; pref = pref_buffer; max_cost_classes_num = 1; FOR_EACH_ALLOCNO (a, ai) { pref[ALLOCNO_NUM (a)] = reg_preferred_class (ALLOCNO_REGNO (a)); setup_regno_cost_classes_by_aclass (ALLOCNO_REGNO (a), pref[ALLOCNO_NUM (a)]); max_cost_classes_num = MAX (max_cost_classes_num, regno_cost_classes[ALLOCNO_REGNO (a)]->num); } start = 1; } else { pref = NULL; max_cost_classes_num = ira_important_classes_num; for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--) if (regno_reg_rtx[i] != NULL_RTX) setup_regno_cost_classes_by_mode (i, PSEUDO_REGNO_MODE (i)); else setup_regno_cost_classes_by_aclass (i, ALL_REGS); start = 0; } if (allocno_p) /* Clear the flag for the next compiled function. */ pseudo_classes_defined_p = false; /* Normally we scan the insns once and determine the best class to use for each allocno. However, if -fexpensive-optimizations are on, we do so twice, the second time using the tentative best classes to guide the selection. */ for (pass = start; pass <= flag_expensive_optimizations; pass++) { if ((!allocno_p || internal_flag_ira_verbose > 0) && dump_file) fprintf (dump_file, "\nPass %i for finding pseudo/allocno costs\n\n", pass); if (pass != start) { max_cost_classes_num = 1; for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--) { setup_regno_cost_classes_by_aclass (i, regno_best_class[i]); max_cost_classes_num = MAX (max_cost_classes_num, regno_cost_classes[i]->num); } } struct_costs_size = sizeof (struct costs) + sizeof (int) * (max_cost_classes_num - 1); /* Zero out our accumulation of the cost of each class for each allocno. */ memset (costs, 0, cost_elements_num * struct_costs_size); if (allocno_p) { /* Scan the instructions and record each time it would save code to put a certain allocno in a certain class. */ ira_traverse_loop_tree (true, ira_loop_tree_root, process_bb_node_for_costs, NULL); memcpy (total_allocno_costs, costs, max_struct_costs_size * ira_allocnos_num); } else { basic_block bb; FOR_EACH_BB (bb) process_bb_for_costs (bb); } if (pass == 0) pref = pref_buffer; /* Now for each allocno look at how desirable each class is and find which class is preferred. */ for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--) { ira_allocno_t a, parent_a; int rclass, a_num, parent_a_num, add_cost; ira_loop_tree_node_t parent; int best_cost, allocno_cost; enum reg_class best, alt_class; cost_classes_t cost_classes_ptr = regno_cost_classes[i]; enum reg_class *cost_classes = cost_classes_ptr->classes; int *i_costs = temp_costs->cost; int i_mem_cost; int equiv_savings = regno_equiv_gains[i]; if (! allocno_p) { if (regno_reg_rtx[i] == NULL_RTX) continue; memcpy (temp_costs, COSTS (costs, i), struct_costs_size); i_mem_cost = temp_costs->mem_cost; } else { if (ira_regno_allocno_map[i] == NULL) continue; memset (temp_costs, 0, struct_costs_size); i_mem_cost = 0; /* Find cost of all allocnos with the same regno. */ for (a = ira_regno_allocno_map[i]; a != NULL; a = ALLOCNO_NEXT_REGNO_ALLOCNO (a)) { int *a_costs, *p_costs; a_num = ALLOCNO_NUM (a); if ((flag_ira_region == IRA_REGION_ALL || flag_ira_region == IRA_REGION_MIXED) && (parent = ALLOCNO_LOOP_TREE_NODE (a)->parent) != NULL && (parent_a = parent->regno_allocno_map[i]) != NULL /* There are no caps yet. */ && bitmap_bit_p (ALLOCNO_LOOP_TREE_NODE (a)->border_allocnos, ALLOCNO_NUM (a))) { /* Propagate costs to upper levels in the region tree. */ parent_a_num = ALLOCNO_NUM (parent_a); a_costs = COSTS (total_allocno_costs, a_num)->cost; p_costs = COSTS (total_allocno_costs, parent_a_num)->cost; for (k = cost_classes_ptr->num - 1; k >= 0; k--) { add_cost = a_costs[k]; if (add_cost > 0 && INT_MAX - add_cost < p_costs[k]) p_costs[k] = INT_MAX; else p_costs[k] += add_cost; } add_cost = COSTS (total_allocno_costs, a_num)->mem_cost; if (add_cost > 0 && (INT_MAX - add_cost < COSTS (total_allocno_costs, parent_a_num)->mem_cost)) COSTS (total_allocno_costs, parent_a_num)->mem_cost = INT_MAX; else COSTS (total_allocno_costs, parent_a_num)->mem_cost += add_cost; } a_costs = COSTS (costs, a_num)->cost; for (k = cost_classes_ptr->num - 1; k >= 0; k--) { add_cost = a_costs[k]; if (add_cost > 0 && INT_MAX - add_cost < i_costs[k]) i_costs[k] = INT_MAX; else i_costs[k] += add_cost; } add_cost = COSTS (costs, a_num)->mem_cost; if (add_cost > 0 && INT_MAX - add_cost < i_mem_cost) i_mem_cost = INT_MAX; else i_mem_cost += add_cost; } } if (equiv_savings < 0) i_mem_cost = -equiv_savings; else if (equiv_savings > 0) { i_mem_cost = 0; for (k = cost_classes_ptr->num - 1; k >= 0; k--) i_costs[k] += equiv_savings; } best_cost = (1 << (HOST_BITS_PER_INT - 2)) - 1; best = ALL_REGS; alt_class = NO_REGS; /* Find best common class for all allocnos with the same regno. */ for (k = 0; k < cost_classes_ptr->num; k++) { rclass = cost_classes[k]; /* Ignore classes that are too small or invalid for this operand. */ if (! contains_reg_of_mode[rclass][PSEUDO_REGNO_MODE (i)] #ifdef CANNOT_CHANGE_MODE_CLASS || invalid_mode_change_p (i, (enum reg_class) rclass) #endif ) continue; if (i_costs[k] < best_cost) { best_cost = i_costs[k]; best = (enum reg_class) rclass; } else if (i_costs[k] == best_cost) best = ira_reg_class_subunion[best][rclass]; if (pass == flag_expensive_optimizations /* We still prefer registers to memory even at this stage if their costs are the same. We will make a final decision during assigning hard registers when we have all info including more accurate costs which might be affected by assigning hard registers to other pseudos because the pseudos involved in moves can be coalesced. */ && i_costs[k] <= i_mem_cost && (reg_class_size[reg_class_subunion[alt_class][rclass]] > reg_class_size[alt_class])) alt_class = reg_class_subunion[alt_class][rclass]; } alt_class = ira_allocno_class_translate[alt_class]; if (best_cost > i_mem_cost) regno_aclass[i] = NO_REGS; else { /* Make the common class the biggest class of best and alt_class. */ regno_aclass[i] = ira_reg_class_superunion[best][alt_class]; ira_assert (regno_aclass[i] != NO_REGS && ira_reg_allocno_class_p[regno_aclass[i]]); } if (pass == flag_expensive_optimizations) { if (best_cost > i_mem_cost) best = alt_class = NO_REGS; else if (best == alt_class) alt_class = NO_REGS; setup_reg_classes (i, best, alt_class, regno_aclass[i]); if ((!allocno_p || internal_flag_ira_verbose > 2) && dump_file != NULL) fprintf (dump_file, " r%d: preferred %s, alternative %s, allocno %s\n", i, reg_class_names[best], reg_class_names[alt_class], reg_class_names[regno_aclass[i]]); } regno_best_class[i] = best; if (! allocno_p) { pref[i] = best_cost > i_mem_cost ? NO_REGS : best; continue; } for (a = ira_regno_allocno_map[i]; a != NULL; a = ALLOCNO_NEXT_REGNO_ALLOCNO (a)) { a_num = ALLOCNO_NUM (a); if (regno_aclass[i] == NO_REGS) best = NO_REGS; else { int *total_a_costs = COSTS (total_allocno_costs, a_num)->cost; int *a_costs = COSTS (costs, a_num)->cost; /* Finding best class which is subset of the common class. */ best_cost = (1 << (HOST_BITS_PER_INT - 2)) - 1; allocno_cost = best_cost; best = ALL_REGS; for (k = 0; k < cost_classes_ptr->num; k++) { rclass = cost_classes[k]; if (! ira_class_subset_p[rclass][regno_aclass[i]]) continue; /* Ignore classes that are too small or invalid for this operand. */ if (! contains_reg_of_mode[rclass][PSEUDO_REGNO_MODE (i)] #ifdef CANNOT_CHANGE_MODE_CLASS || invalid_mode_change_p (i, (enum reg_class) rclass) #endif ) ; else if (total_a_costs[k] < best_cost) { best_cost = total_a_costs[k]; allocno_cost = a_costs[k]; best = (enum reg_class) rclass; } else if (total_a_costs[k] == best_cost) { best = ira_reg_class_subunion[best][rclass]; allocno_cost = MAX (allocno_cost, a_costs[k]); } } ALLOCNO_CLASS_COST (a) = allocno_cost; } if (internal_flag_ira_verbose > 2 && dump_file != NULL && (pass == 0 || pref[a_num] != best)) { fprintf (dump_file, " a%d (r%d,", a_num, i); if ((bb = ALLOCNO_LOOP_TREE_NODE (a)->bb) != NULL) fprintf (dump_file, "b%d", bb->index); else fprintf (dump_file, "l%d", ALLOCNO_LOOP_TREE_NODE (a)->loop_num); fprintf (dump_file, ") best %s, allocno %s\n", reg_class_names[best], reg_class_names[regno_aclass[i]]); } pref[a_num] = best; } } if (internal_flag_ira_verbose > 4 && dump_file) { if (allocno_p) print_allocno_costs (dump_file); else print_pseudo_costs (dump_file); fprintf (dump_file,"\n"); } } ira_free (regno_best_class); } /* Process moves involving hard regs to modify allocno hard register costs. We can do this only after determining allocno class. If a hard register forms a register class, than moves with the hard register are already taken into account in class costs for the allocno. */ static void process_bb_node_for_hard_reg_moves (ira_loop_tree_node_t loop_tree_node) { int i, freq, cost, src_regno, dst_regno, hard_regno; bool to_p; ira_allocno_t a; enum reg_class rclass, hard_reg_class; enum machine_mode mode; basic_block bb; rtx insn, set, src, dst; bb = loop_tree_node->bb; if (bb == NULL) return; freq = REG_FREQ_FROM_BB (bb); if (freq == 0) freq = 1; FOR_BB_INSNS (bb, insn) { if (!NONDEBUG_INSN_P (insn)) continue; set = single_set (insn); if (set == NULL_RTX) continue; dst = SET_DEST (set); src = SET_SRC (set); if (! REG_P (dst) || ! REG_P (src)) continue; dst_regno = REGNO (dst); src_regno = REGNO (src); if (dst_regno >= FIRST_PSEUDO_REGISTER && src_regno < FIRST_PSEUDO_REGISTER) { hard_regno = src_regno; to_p = true; a = ira_curr_regno_allocno_map[dst_regno]; } else if (src_regno >= FIRST_PSEUDO_REGISTER && dst_regno < FIRST_PSEUDO_REGISTER) { hard_regno = dst_regno; to_p = false; a = ira_curr_regno_allocno_map[src_regno]; } else continue; rclass = ALLOCNO_CLASS (a); if (! TEST_HARD_REG_BIT (reg_class_contents[rclass], hard_regno)) continue; i = ira_class_hard_reg_index[rclass][hard_regno]; if (i < 0) continue; mode = ALLOCNO_MODE (a); hard_reg_class = REGNO_REG_CLASS (hard_regno); ira_init_register_move_cost_if_necessary (mode); cost = (to_p ? ira_register_move_cost[mode][hard_reg_class][rclass] : ira_register_move_cost[mode][rclass][hard_reg_class]) * freq; ira_allocate_and_set_costs (&ALLOCNO_HARD_REG_COSTS (a), rclass, ALLOCNO_CLASS_COST (a)); ira_allocate_and_set_costs (&ALLOCNO_CONFLICT_HARD_REG_COSTS (a), rclass, 0); ALLOCNO_HARD_REG_COSTS (a)[i] -= cost; ALLOCNO_CONFLICT_HARD_REG_COSTS (a)[i] -= cost; ALLOCNO_CLASS_COST (a) = MIN (ALLOCNO_CLASS_COST (a), ALLOCNO_HARD_REG_COSTS (a)[i]); } } /* After we find hard register and memory costs for allocnos, define its class and modify hard register cost because insns moving allocno to/from hard registers. */ static void setup_allocno_class_and_costs (void) { int i, j, n, regno, hard_regno, num; int *reg_costs; enum reg_class aclass, rclass; ira_allocno_t a; ira_allocno_iterator ai; cost_classes_t cost_classes_ptr; ira_assert (allocno_p); FOR_EACH_ALLOCNO (a, ai) { i = ALLOCNO_NUM (a); regno = ALLOCNO_REGNO (a); aclass = regno_aclass[regno]; cost_classes_ptr = regno_cost_classes[regno]; ira_assert (pref[i] == NO_REGS || aclass != NO_REGS); ALLOCNO_MEMORY_COST (a) = COSTS (costs, i)->mem_cost; ira_set_allocno_class (a, aclass); if (aclass == NO_REGS) continue; if (optimize && ALLOCNO_CLASS (a) != pref[i]) { n = ira_class_hard_regs_num[aclass]; ALLOCNO_HARD_REG_COSTS (a) = reg_costs = ira_allocate_cost_vector (aclass); for (j = n - 1; j >= 0; j--) { hard_regno = ira_class_hard_regs[aclass][j]; if (TEST_HARD_REG_BIT (reg_class_contents[pref[i]], hard_regno)) reg_costs[j] = ALLOCNO_CLASS_COST (a); else { rclass = REGNO_REG_CLASS (hard_regno); num = cost_classes_ptr->index[rclass]; if (num < 0) { num = cost_classes_ptr->hard_regno_index[hard_regno]; ira_assert (num >= 0); } reg_costs[j] = COSTS (costs, i)->cost[num]; } } } } if (optimize) ira_traverse_loop_tree (true, ira_loop_tree_root, process_bb_node_for_hard_reg_moves, NULL); } /* Function called once during compiler work. */ void ira_init_costs_once (void) { int i; init_cost = NULL; for (i = 0; i < MAX_RECOG_OPERANDS; i++) { op_costs[i] = NULL; this_op_costs[i] = NULL; } temp_costs = NULL; } /* Free allocated temporary cost vectors. */ static void free_ira_costs (void) { int i; free (init_cost); init_cost = NULL; for (i = 0; i < MAX_RECOG_OPERANDS; i++) { free (op_costs[i]); free (this_op_costs[i]); op_costs[i] = this_op_costs[i] = NULL; } free (temp_costs); temp_costs = NULL; } /* This is called each time register related information is changed. */ void ira_init_costs (void) { int i; free_ira_costs (); max_struct_costs_size = sizeof (struct costs) + sizeof (int) * (ira_important_classes_num - 1); /* Don't use ira_allocate because vectors live through several IRA calls. */ init_cost = (struct costs *) xmalloc (max_struct_costs_size); init_cost->mem_cost = 1000000; for (i = 0; i < ira_important_classes_num; i++) init_cost->cost[i] = 1000000; for (i = 0; i < MAX_RECOG_OPERANDS; i++) { op_costs[i] = (struct costs *) xmalloc (max_struct_costs_size); this_op_costs[i] = (struct costs *) xmalloc (max_struct_costs_size); } temp_costs = (struct costs *) xmalloc (max_struct_costs_size); } /* Function called once at the end of compiler work. */ void ira_finish_costs_once (void) { free_ira_costs (); } /* Common initialization function for ira_costs and ira_set_pseudo_classes. */ static void init_costs (void) { init_subregs_of_mode (); costs = (struct costs *) ira_allocate (max_struct_costs_size * cost_elements_num); pref_buffer = (enum reg_class *) ira_allocate (sizeof (enum reg_class) * cost_elements_num); regno_aclass = (enum reg_class *) ira_allocate (sizeof (enum reg_class) * max_reg_num ()); regno_equiv_gains = (int *) ira_allocate (sizeof (int) * max_reg_num ()); memset (regno_equiv_gains, 0, sizeof (int) * max_reg_num ()); } /* Common finalization function for ira_costs and ira_set_pseudo_classes. */ static void finish_costs (void) { finish_subregs_of_mode (); ira_free (regno_equiv_gains); ira_free (regno_aclass); ira_free (pref_buffer); ira_free (costs); } /* Entry function which defines register class, memory and hard register costs for each allocno. */ void ira_costs (void) { allocno_p = true; cost_elements_num = ira_allocnos_num; init_costs (); total_allocno_costs = (struct costs *) ira_allocate (max_struct_costs_size * ira_allocnos_num); initiate_regno_cost_classes (); calculate_elim_costs_all_insns (); find_costs_and_classes (ira_dump_file); setup_allocno_class_and_costs (); finish_regno_cost_classes (); finish_costs (); ira_free (total_allocno_costs); } /* Entry function which defines classes for pseudos. */ void ira_set_pseudo_classes (FILE *dump_file) { allocno_p = false; internal_flag_ira_verbose = flag_ira_verbose; cost_elements_num = max_reg_num (); init_costs (); initiate_regno_cost_classes (); find_costs_and_classes (dump_file); finish_regno_cost_classes (); pseudo_classes_defined_p = true; finish_costs (); } /* Change hard register costs for allocnos which lives through function calls. This is called only when we found all intersected calls during building allocno live ranges. */ void ira_tune_allocno_costs (void) { int j, n, regno; int cost, min_cost, *reg_costs; enum reg_class aclass, rclass; enum machine_mode mode; ira_allocno_t a; ira_allocno_iterator ai; ira_allocno_object_iterator oi; ira_object_t obj; bool skip_p; FOR_EACH_ALLOCNO (a, ai) { aclass = ALLOCNO_CLASS (a); if (aclass == NO_REGS) continue; mode = ALLOCNO_MODE (a); n = ira_class_hard_regs_num[aclass]; min_cost = INT_MAX; if (ALLOCNO_CALLS_CROSSED_NUM (a) != 0) { ira_allocate_and_set_costs (&ALLOCNO_HARD_REG_COSTS (a), aclass, ALLOCNO_CLASS_COST (a)); reg_costs = ALLOCNO_HARD_REG_COSTS (a); for (j = n - 1; j >= 0; j--) { regno = ira_class_hard_regs[aclass][j]; skip_p = false; FOR_EACH_ALLOCNO_OBJECT (a, obj, oi) { if (ira_hard_reg_set_intersection_p (regno, mode, OBJECT_CONFLICT_HARD_REGS (obj))) { skip_p = true; break; } } if (skip_p) continue; rclass = REGNO_REG_CLASS (regno); cost = 0; if (ira_hard_reg_set_intersection_p (regno, mode, call_used_reg_set) || HARD_REGNO_CALL_PART_CLOBBERED (regno, mode)) cost += (ALLOCNO_CALL_FREQ (a) * (ira_memory_move_cost[mode][rclass][0] + ira_memory_move_cost[mode][rclass][1])); #ifdef IRA_HARD_REGNO_ADD_COST_MULTIPLIER cost += ((ira_memory_move_cost[mode][rclass][0] + ira_memory_move_cost[mode][rclass][1]) * ALLOCNO_FREQ (a) * IRA_HARD_REGNO_ADD_COST_MULTIPLIER (regno) / 2); #endif if (INT_MAX - cost < reg_costs[j]) reg_costs[j] = INT_MAX; else reg_costs[j] += cost; if (min_cost > reg_costs[j]) min_cost = reg_costs[j]; } } if (min_cost != INT_MAX) ALLOCNO_CLASS_COST (a) = min_cost; /* Some targets allow pseudos to be allocated to unaligned sequences of hard registers. However, selecting an unaligned sequence can unnecessarily restrict later allocations. So increase the cost of unaligned hard regs to encourage the use of aligned hard regs. */ { const int nregs = ira_reg_class_max_nregs[aclass][ALLOCNO_MODE (a)]; if (nregs > 1) { ira_allocate_and_set_costs (&ALLOCNO_HARD_REG_COSTS (a), aclass, ALLOCNO_CLASS_COST (a)); reg_costs = ALLOCNO_HARD_REG_COSTS (a); for (j = n - 1; j >= 0; j--) { regno = ira_non_ordered_class_hard_regs[aclass][j]; if ((regno % nregs) != 0) { int index = ira_class_hard_reg_index[aclass][regno]; ira_assert (index != -1); reg_costs[index] += ALLOCNO_FREQ (a); } } } } } } /* Add COST to the estimated gain for eliminating REGNO with its equivalence. If COST is zero, record that no such elimination is possible. */ void ira_adjust_equiv_reg_cost (unsigned regno, int cost) { if (cost == 0) regno_equiv_gains[regno] = 0; else regno_equiv_gains[regno] += cost; }
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