diff options
Diffstat (limited to 'gcc/regmove.c')
-rw-r--r-- | gcc/regmove.c | 116 |
1 files changed, 92 insertions, 24 deletions
diff --git a/gcc/regmove.c b/gcc/regmove.c index 05effa66cfd..c54879bc3a7 100644 --- a/gcc/regmove.c +++ b/gcc/regmove.c @@ -1,6 +1,7 @@ /* Move registers around to reduce number of move instructions needed. - Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, - 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. + Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, + 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 + Free Software Foundation, Inc. This file is part of GCC. @@ -45,7 +46,7 @@ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA #include "reload.h" #include "timevar.h" #include "tree-pass.h" - +#include "df.h" static int perhaps_ends_bb_p (rtx); static int optimize_reg_copy_1 (rtx, rtx, rtx); @@ -85,6 +86,72 @@ regclass_compatible_p (int class0, int class1) && ! CLASS_LIKELY_SPILLED_P (class1))); } +/* Find the place in the rtx X where REG is used as a memory address. + Return the MEM rtx that so uses it. + If PLUSCONST is nonzero, search instead for a memory address equivalent to + (plus REG (const_int PLUSCONST)). + + If such an address does not appear, return 0. + If REG appears more than once, or is used other than in such an address, + return (rtx) 1. */ + +static rtx +find_use_as_address (rtx x, rtx reg, HOST_WIDE_INT plusconst) +{ + enum rtx_code code = GET_CODE (x); + const char * const fmt = GET_RTX_FORMAT (code); + int i; + rtx value = 0; + rtx tem; + + if (code == MEM && XEXP (x, 0) == reg && plusconst == 0) + return x; + + if (code == MEM && GET_CODE (XEXP (x, 0)) == PLUS + && XEXP (XEXP (x, 0), 0) == reg + && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT + && INTVAL (XEXP (XEXP (x, 0), 1)) == plusconst) + return x; + + if (code == SIGN_EXTRACT || code == ZERO_EXTRACT) + { + /* If REG occurs inside a MEM used in a bit-field reference, + that is unacceptable. */ + if (find_use_as_address (XEXP (x, 0), reg, 0) != 0) + return (rtx) (size_t) 1; + } + + if (x == reg) + return (rtx) (size_t) 1; + + for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) + { + if (fmt[i] == 'e') + { + tem = find_use_as_address (XEXP (x, i), reg, plusconst); + if (value == 0) + value = tem; + else if (tem != 0) + return (rtx) (size_t) 1; + } + else if (fmt[i] == 'E') + { + int j; + for (j = XVECLEN (x, i) - 1; j >= 0; j--) + { + tem = find_use_as_address (XVECEXP (x, i, j), reg, plusconst); + if (value == 0) + value = tem; + else if (tem != 0) + return (rtx) (size_t) 1; + } + } + } + + return value; +} + + /* INC_INSN is an instruction that adds INCREMENT to REG. Try to fold INC_INSN as a post/pre in/decrement into INSN. Iff INC_INSN_SET is nonzero, inc_insn has a destination different from src. @@ -258,8 +325,7 @@ mark_flags_life_zones (rtx flags) { int i; for (i = 0; i < flags_nregs; ++i) - live |= REGNO_REG_SET_P (block->il.rtl->global_live_at_start, - flags_regno + i); + live |= REGNO_REG_SET_P (DF_LIVE_IN (block), flags_regno + i); } #endif @@ -612,7 +678,10 @@ optimize_reg_copy_2 (rtx insn, rtx dest, rtx src) if (INSN_P (q)) { if (reg_mentioned_p (dest, PATTERN (q))) - PATTERN (q) = replace_rtx (PATTERN (q), dest, src); + { + PATTERN (q) = replace_rtx (PATTERN (q), dest, src); + df_insn_rescan (q); + } if (CALL_P (q)) { @@ -801,20 +870,11 @@ copy_src_to_dest (rtx insn, rtx src, rtx dest) /* Update the various register tables. */ dest_regno = REGNO (dest); - REG_N_SETS (dest_regno) ++; + INC_REG_N_SETS (dest_regno, 1); REG_LIVE_LENGTH (dest_regno)++; - if (REGNO_FIRST_UID (dest_regno) == insn_uid) - REGNO_FIRST_UID (dest_regno) = move_uid; - src_regno = REGNO (src); if (! find_reg_note (move_insn, REG_DEAD, src)) REG_LIVE_LENGTH (src_regno)++; - - if (REGNO_FIRST_UID (src_regno) == insn_uid) - REGNO_FIRST_UID (src_regno) = move_uid; - - if (REGNO_LAST_UID (src_regno) == insn_uid) - REGNO_LAST_UID (src_regno) = move_uid; } } @@ -1026,6 +1086,12 @@ regmove_optimize (rtx f, int nregs) if (flag_non_call_exceptions) return; + df_note_add_problem (); + df_analyze (); + + regstat_init_n_sets_and_refs (); + regstat_compute_ri (); + /* Find out where a potential flags register is live, and so that we can suppress some optimizations in those zones. */ mark_flags_life_zones (discover_flags_reg ()); @@ -1427,8 +1493,8 @@ regmove_optimize (rtx f, int nregs) dstno = REGNO (dst); srcno = REGNO (src); - REG_N_SETS (dstno)++; - REG_N_SETS (srcno)--; + INC_REG_N_SETS (dstno, 1); + INC_REG_N_SETS (srcno, -1); REG_N_CALLS_CROSSED (dstno) += num_calls; REG_N_CALLS_CROSSED (srcno) -= num_calls; @@ -1457,7 +1523,6 @@ regmove_optimize (rtx f, int nregs) alternative approach of copying the source to the destination. */ if (!success && copy_src != NULL_RTX) copy_src_to_dest (insn, copy_src, copy_dst); - } } @@ -1469,6 +1534,8 @@ regmove_optimize (rtx f, int nregs) free (reg_set_in_bb); reg_set_in_bb = NULL; } + regstat_free_n_sets_and_refs (); + regstat_free_ri (); } /* Returns nonzero if INSN's pattern has matching constraints for any operand. @@ -1823,7 +1890,7 @@ fixup_match_1 (rtx insn, rtx set, rtx src, rtx src_subreg, rtx dst, && try_auto_increment (search_end, post_inc, 0, src, newconst, 1)) post_inc = 0; validate_change (insn, &XEXP (SET_SRC (set), 1), GEN_INT (insn_const), 0); - REG_N_SETS (REGNO (src))++; + INC_REG_N_SETS (REGNO (src), 1); REG_LIVE_LENGTH (REGNO (src))++; } if (overlap) @@ -1844,6 +1911,7 @@ fixup_match_1 (rtx insn, rtx set, rtx src, rtx src_subreg, rtx dst, p = emit_insn_after_setloc (pat, PREV_INSN (p), INSN_LOCATOR (insn)); delete_insn (insn); REG_NOTES (p) = notes; + df_notes_rescan (p); } } /* Sometimes we'd generate src = const; src += n; @@ -1889,7 +1957,7 @@ fixup_match_1 (rtx insn, rtx set, rtx src, rtx src_subreg, rtx dst, && validate_change (insn, &SET_SRC (set), XEXP (note, 0), 0)) { delete_insn (q); - REG_N_SETS (REGNO (src))--; + INC_REG_N_SETS (REGNO (src), -1); REG_N_CALLS_CROSSED (REGNO (src)) -= num_calls2; REG_LIVE_LENGTH (REGNO (src)) -= s_length2; insn_const = 0; @@ -1961,8 +2029,8 @@ fixup_match_1 (rtx insn, rtx set, rtx src, rtx src_subreg, rtx dst, REG_N_CALLS_CROSSED (REGNO (src)) += s_num_calls; } - REG_N_SETS (REGNO (src))++; - REG_N_SETS (REGNO (dst))--; + INC_REG_N_SETS (REGNO (src), 1); + INC_REG_N_SETS (REGNO (dst), -1); REG_N_CALLS_CROSSED (REGNO (dst)) -= num_calls; @@ -2038,7 +2106,6 @@ static unsigned int rest_of_handle_regmove (void) { regmove_optimize (get_insns (), max_reg_num ()); - cleanup_cfg (CLEANUP_EXPENSIVE | CLEANUP_UPDATE_LIFE); return 0; } @@ -2055,6 +2122,7 @@ struct tree_opt_pass pass_regmove = 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ + TODO_df_finish | TODO_dump_func | TODO_ggc_collect, /* todo_flags_finish */ 'N' /* letter */ |