diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 13 | ||||
| -rw-r--r-- | gcc/lra-remat.c | 115 |
2 files changed, 90 insertions, 38 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index a2fb881..66deab1 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,15 @@ +2016-02-08 Bernd Schmidt <bschmidt@redhat.com> + + PR rtl-optimization/68730 + * lra-remat.c (insn_to_cand_activation): New static variable. + (lra_remat): Allocate and free it. + (create_cand): New arg activation. Initialize a field in + insn_to_cand_activation if it is nonnull. + (create_cands): Pass the activation insn to create_cand when making + a candidate involving an output reload. Reorganize code a little. + (do_remat): Keep track of active status of candidates in a separate + bitmap. + 2016-02-08 Richard Biener <rguenther@suse.de> PR tree-optimization/69719 @@ -30,7 +42,6 @@ * tree-ssa-scopedtables.c (const_and_copies::record_const_or_copy_raw): New, factored out of (const_and_copies::record_const_or_copy): Call new member function. - 2016-02-05 Jeff Law <law@redhat.com> diff --git a/gcc/lra-remat.c b/gcc/lra-remat.c index e729ea9..785d531 100644 --- a/gcc/lra-remat.c +++ b/gcc/lra-remat.c @@ -112,6 +112,10 @@ static vec<cand_t> all_cands; /* Map: insn -> candidate representing it. It is null if the insn can not be used for rematerialization. */ static cand_t *insn_to_cand; +/* A secondary map, for candidates that involve two insns, where the + second one makes the equivalence. The candidate must not be used + before seeing this activation insn. */ +static cand_t *insn_to_cand_activation; /* Map regno -> candidates can be used for the regno rematerialization. */ @@ -461,7 +465,7 @@ operand_to_remat (rtx_insn *insn) REGNO. Insert the candidate into the table and set up the corresponding INSN_TO_CAND element. */ static void -create_cand (rtx_insn *insn, int nop, int regno) +create_cand (rtx_insn *insn, int nop, int regno, rtx_insn *activation = NULL) { lra_insn_recog_data_t id = lra_get_insn_recog_data (insn); rtx reg = *id->operand_loc[nop]; @@ -486,6 +490,8 @@ create_cand (rtx_insn *insn, int nop, int regno) cand->next_regno_cand = regno_cands[cand->regno]; regno_cands[cand->regno] = cand; } + if (activation) + insn_to_cand_activation[INSN_UID (activation)] = cand_in_table; } /* Create rematerialization candidates (inserting them into the @@ -504,43 +510,55 @@ create_cands (void) /* Create candidates. */ regno_potential_cand = XCNEWVEC (struct potential_cand, max_reg_num ()); for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) - if (INSN_P (insn)) + if (NONDEBUG_INSN_P (insn)) { - rtx set; - int src_regno, dst_regno; - rtx_insn *insn2; lra_insn_recog_data_t id = lra_get_insn_recog_data (insn); - int nop = operand_to_remat (insn); - int regno = -1; - - if ((set = single_set (insn)) != NULL - && REG_P (SET_SRC (set)) && REG_P (SET_DEST (set)) - && ((src_regno = REGNO (SET_SRC (set))) - >= lra_constraint_new_regno_start) - && (dst_regno = REGNO (SET_DEST (set))) >= FIRST_PSEUDO_REGISTER - && reg_renumber[dst_regno] < 0 - && (insn2 = regno_potential_cand[src_regno].insn) != NULL - && BLOCK_FOR_INSN (insn2) == BLOCK_FOR_INSN (insn)) - /* It is an output reload insn after insn can be - rematerialized (potential candidate). */ - create_cand (insn2, regno_potential_cand[src_regno].nop, dst_regno); - if (nop < 0) - goto fail; - gcc_assert (REG_P (*id->operand_loc[nop])); - regno = REGNO (*id->operand_loc[nop]); - gcc_assert (regno >= FIRST_PSEUDO_REGISTER); - if (reg_renumber[regno] < 0) - create_cand (insn, nop, regno); - else + int keep_regno = -1; + rtx set = single_set (insn); + int nop; + + /* See if this is an output reload for a previous insn. */ + if (set != NULL + && REG_P (SET_SRC (set)) && REG_P (SET_DEST (set))) + { + rtx dstreg = SET_DEST (set); + int src_regno = REGNO (SET_SRC (set)); + int dst_regno = REGNO (dstreg); + rtx_insn *insn2 = regno_potential_cand[src_regno].insn; + + if (insn2 != NULL + && dst_regno >= FIRST_PSEUDO_REGISTER + && reg_renumber[dst_regno] < 0 + && BLOCK_FOR_INSN (insn2) == BLOCK_FOR_INSN (insn)) + { + create_cand (insn2, regno_potential_cand[src_regno].nop, + dst_regno, insn); + goto done; + } + } + + nop = operand_to_remat (insn); + if (nop >= 0) { - regno_potential_cand[regno].insn = insn; - regno_potential_cand[regno].nop = nop; - goto fail; + gcc_assert (REG_P (*id->operand_loc[nop])); + int regno = REGNO (*id->operand_loc[nop]); + gcc_assert (regno >= FIRST_PSEUDO_REGISTER); + /* If we're setting an unrenumbered pseudo, make a candidate immediately. + If it's an output reload register, save it for later; the code above + looks for output reload insns later on. */ + if (reg_renumber[regno] < 0) + create_cand (insn, nop, regno); + else if (regno >= lra_constraint_new_regno_start) + { + regno_potential_cand[regno].insn = insn; + regno_potential_cand[regno].nop = nop; + keep_regno = regno; + } } - regno = -1; - fail: + + done: for (struct lra_insn_reg *reg = id->regs; reg != NULL; reg = reg->next) - if (reg->type != OP_IN && reg->regno != regno + if (reg->type != OP_IN && reg->regno != keep_regno && reg->regno >= FIRST_PSEUDO_REGISTER) regno_potential_cand[reg->regno].insn = NULL; } @@ -1072,16 +1090,21 @@ do_remat (void) rtx_insn *insn; basic_block bb; bitmap_head avail_cands; + bitmap_head active_cands; bool changed_p = false; /* Living hard regs and hard registers of living pseudos. */ HARD_REG_SET live_hard_regs; bitmap_initialize (&avail_cands, ®_obstack); + bitmap_initialize (&active_cands, ®_obstack); FOR_EACH_BB_FN (bb, cfun) { REG_SET_TO_HARD_REG_SET (live_hard_regs, df_get_live_out (bb)); bitmap_and (&avail_cands, &get_remat_bb_data (bb)->avin_cands, &get_remat_bb_data (bb)->livein_cands); + /* Activating insns are always in the same block as their corresponding + remat insn, so at the start of a block the two bitsets are equal. */ + bitmap_copy (&active_cands, &avail_cands); FOR_BB_INSNS (bb, insn) { if (!NONDEBUG_INSN_P (insn)) @@ -1115,7 +1138,8 @@ do_remat (void) for (cand = regno_cands[src_regno]; cand != NULL; cand = cand->next_regno_cand) - if (bitmap_bit_p (&avail_cands, cand->index)) + if (bitmap_bit_p (&avail_cands, cand->index) + && bitmap_bit_p (&active_cands, cand->index)) break; } int i, hard_regno, nregs; @@ -1209,9 +1233,23 @@ do_remat (void) } bitmap_and_compl_into (&avail_cands, &temp_bitmap); - if ((cand = insn_to_cand[INSN_UID (insn)]) != NULL) - bitmap_set_bit (&avail_cands, cand->index); - + + /* Now see whether a candidate is made active or available + by this insn. */ + cand = insn_to_cand_activation[INSN_UID (insn)]; + if (cand) + bitmap_set_bit (&active_cands, cand->index); + + cand = insn_to_cand[INSN_UID (insn)]; + if (cand != NULL) + { + bitmap_set_bit (&avail_cands, cand->index); + if (cand->reload_regno == -1) + bitmap_set_bit (&active_cands, cand->index); + else + bitmap_clear_bit (&active_cands, cand->index); + } + if (remat_insn != NULL) { HOST_WIDE_INT sp_offset_change = cand_sp_offset - id->sp_offset; @@ -1258,6 +1296,7 @@ do_remat (void) } } bitmap_clear (&avail_cands); + bitmap_clear (&active_cands); return changed_p; } @@ -1286,6 +1325,7 @@ lra_remat (void) lra_rematerialization_iter); timevar_push (TV_LRA_REMAT); insn_to_cand = XCNEWVEC (cand_t, get_max_uid ()); + insn_to_cand_activation = XCNEWVEC (cand_t, get_max_uid ()); regno_cands = XCNEWVEC (cand_t, max_regno); all_cands.create (8000); call_used_regs_arr_len = 0; @@ -1314,6 +1354,7 @@ lra_remat (void) bitmap_clear (&all_blocks); free (regno_cands); free (insn_to_cand); + free (insn_to_cand_activation); timevar_pop (TV_LRA_REMAT); return result; } |