diff options
Diffstat (limited to 'gcc/config/epiphany/resolve-sw-modes.c')
| -rw-r--r-- | gcc/config/epiphany/resolve-sw-modes.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/gcc/config/epiphany/resolve-sw-modes.c b/gcc/config/epiphany/resolve-sw-modes.c new file mode 100644 index 00000000000..9564d752c4f --- /dev/null +++ b/gcc/config/epiphany/resolve-sw-modes.c @@ -0,0 +1,182 @@ +/* Mode switching cleanup pass for the EPIPHANY cpu. + Copyright (C) 2000, 2011 Free Software Foundation, Inc. + Contributed by Embecosm on behalf of Adapteva, Inc. + +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 "machmode.h" +#include "tm.h" +#include "hard-reg-set.h" +#include "tm_p.h" +#include "vec.h" +#include "sbitmap.h" +#include "basic-block.h" +#include "df.h" +#include "rtl.h" +#include "insn-config.h" +#include "insn-codes.h" +#include "emit-rtl.h" +#include "recog.h" +#include "function.h" +#include "insn-attr-common.h" +#include "tree-pass.h" + +/* Clean-up after mode switching: + Check for mode setting insns that have FP_MODE_ROUND_UNKNOWN. + If only one rounding mode is required, select that one. + Else we have to choose one to use in this mode setting insn and + insert new mode setting insns on the edges where the other mode + becomes unambigous. */ + +static bool +gate_resolve_sw_modes (void) +{ + return optimize; +} + +static unsigned +resolve_sw_modes (void) +{ + basic_block bb; + rtx insn, src; + VEC (basic_block, heap) *todo; + sbitmap pushed; + bool need_commit = false; + bool finalize_fp_sets = (MACHINE_FUNCTION (cfun)->unknown_mode_sets == 0); + + todo = VEC_alloc (basic_block, heap, last_basic_block); + pushed = sbitmap_alloc (last_basic_block); + sbitmap_zero (pushed); + if (!finalize_fp_sets) + { + df_note_add_problem (); + df_analyze (); + } + FOR_EACH_BB (bb) + FOR_BB_INSNS (bb, insn) + { + enum attr_fp_mode selected_mode; + + if (!NONJUMP_INSN_P (insn) + || recog_memoized (insn) != CODE_FOR_set_fp_mode) + continue; + src = SET_SRC (XVECEXP (PATTERN (insn), 0, 0)); + if (finalize_fp_sets) + { + SET_SRC (XVECEXP (PATTERN (insn), 0, 2)) = copy_rtx (src); + if (REG_P (src)) + df_insn_rescan (insn); + continue; + } + if (REG_P (src) + || XINT (XVECEXP (XEXP (src, 0), 0, 0), 0) != FP_MODE_ROUND_UNKNOWN) + continue; + if (find_regno_note (insn, REG_UNUSED, FP_TRUNCATE_REGNUM)) + selected_mode = FP_MODE_ROUND_NEAREST; + else if (find_regno_note (insn, REG_UNUSED, FP_NEAREST_REGNUM)) + selected_mode = FP_MODE_ROUND_TRUNC; + else + { + /* We could get more fancy in the selection of the mode by + checking the total frequency of the affected edges. */ + selected_mode = (enum attr_fp_mode) epiphany_normal_fp_rounding; + + VEC_quick_push (basic_block, todo, bb); + SET_BIT (pushed, bb->index); + } + XVECEXP (XEXP (src, 0), 0, 0) = GEN_INT (selected_mode); + SET_SRC (XVECEXP (PATTERN (insn), 0, 1)) = copy_rtx (src); + SET_SRC (XVECEXP (PATTERN (insn), 0, 2)) = copy_rtx (src); + df_insn_rescan (insn); + } + while (VEC_length (basic_block, todo)) + { + basic_block bb = VEC_pop (basic_block, todo); + int selected_reg, jilted_reg; + enum attr_fp_mode jilted_mode; + edge e; + edge_iterator ei; + + SET_BIT (pushed, bb->index); + SET_BIT (pushed, bb->index); + + if (epiphany_normal_fp_rounding == FP_MODE_ROUND_NEAREST) + { + selected_reg = FP_NEAREST_REGNUM; + jilted_reg = FP_TRUNCATE_REGNUM; + jilted_mode = FP_MODE_ROUND_TRUNC; + } + else + { + selected_reg = FP_TRUNCATE_REGNUM; + jilted_reg = FP_NEAREST_REGNUM; + jilted_mode = FP_MODE_ROUND_NEAREST; + } + + FOR_EACH_EDGE (e, ei, bb->succs) + { + basic_block succ = e->dest; + rtx seq; + + if (!REGNO_REG_SET_P (DF_LIVE_IN (succ), jilted_reg)) + continue; + if (REGNO_REG_SET_P (DF_LIVE_IN (succ), selected_reg)) + { + if (TEST_BIT (pushed, succ->index)) + continue; + VEC_quick_push (basic_block, todo, succ); + SET_BIT (pushed, bb->index); + continue; + } + start_sequence (); + emit_set_fp_mode (EPIPHANY_MSW_ENTITY_ROUND_UNKNOWN, + jilted_mode, NULL); + seq = get_insns (); + end_sequence (); + need_commit = true; + insert_insn_on_edge (seq, e); + } + } + VEC_free (basic_block, heap, todo); + sbitmap_free (pushed); + if (need_commit) + commit_edge_insertions (); + return 0; +} + +struct rtl_opt_pass pass_resolve_sw_modes = +{ + { + RTL_PASS, + "resolve_sw_modes", /* name */ + gate_resolve_sw_modes, /* gate */ + resolve_sw_modes, /* execute */ + NULL, /* sub */ + NULL, /* next */ + 0, /* static_pass_number */ + TV_MODE_SWITCH, /* tv_id */ + 0, /* properties_required */ + 0, /* properties_provided */ + 0, /* properties_destroyed */ + 0, /* todo_flags_start */ + TODO_df_finish | TODO_verify_rtl_sharing | + 0 /* todo_flags_finish */ + } +}; |