diff options
Diffstat (limited to 'gcc/cse.c')
| -rw-r--r-- | gcc/cse.c | 166 |
1 files changed, 102 insertions, 64 deletions
@@ -1,5 +1,5 @@ /* Common subexpression elimination for GNU compiler. - Copyright (C) 1987-2016 Free Software Foundation, Inc. + Copyright (C) 1987-2017 Free Software Foundation, Inc. This file is part of GCC. @@ -26,6 +26,7 @@ along with GCC; see the file COPYING3. If not see #include "tree.h" #include "cfghooks.h" #include "df.h" +#include "memmodel.h" #include "tm_p.h" #include "insn-config.h" #include "regs.h" @@ -42,10 +43,6 @@ along with GCC; see the file COPYING3. If not see #include "dbgcnt.h" #include "rtl-iter.h" -#ifndef LOAD_EXTEND_OP -#define LOAD_EXTEND_OP(M) UNKNOWN -#endif - /* The basic idea of common subexpression elimination is to go through the code, keeping a record of expressions that would have the same value at the current scan point, and replacing @@ -2364,7 +2361,7 @@ hash_rtx_cb (const_rtx x, machine_mode mode, /* We don't hash on the address of the CODE_LABEL to avoid bootstrap differences and differences between each stage's debugging dumps. */ hash += (((unsigned int) LABEL_REF << 7) - + CODE_LABEL_NUMBER (LABEL_REF_LABEL (x))); + + CODE_LABEL_NUMBER (label_ref_label (x))); return hash; case SYMBOL_REF: @@ -2617,7 +2614,7 @@ exp_equiv_p (const_rtx x, const_rtx y, int validate, bool for_gcse) return x == y; case LABEL_REF: - return LABEL_REF_LABEL (x) == LABEL_REF_LABEL (y); + return label_ref_label (x) == label_ref_label (y); case SYMBOL_REF: return XSTR (x, 0) == XSTR (y, 0); @@ -3054,7 +3051,7 @@ find_comparison_args (enum rtx_code code, rtx *parg1, rtx *parg2, with floating-point operands. */ if (reverse_code) { - enum rtx_code reversed = reversed_comparison_code (x, NULL_RTX); + enum rtx_code reversed = reversed_comparison_code (x, NULL); if (reversed == UNKNOWN) break; else @@ -3506,7 +3503,7 @@ fold_rtx (rtx x, rtx_insn *insn) : lookup_as_function (folded_arg0, MINUS); if (y != 0 && GET_CODE (XEXP (y, 1)) == LABEL_REF - && LABEL_REF_LABEL (XEXP (y, 1)) == LABEL_REF_LABEL (const_arg1)) + && label_ref_label (XEXP (y, 1)) == label_ref_label (const_arg1)) return XEXP (y, 0); /* Now try for a CONST of a MINUS like the above. */ @@ -3514,7 +3511,7 @@ fold_rtx (rtx x, rtx_insn *insn) : lookup_as_function (folded_arg0, CONST))) != 0 && GET_CODE (XEXP (y, 0)) == MINUS && GET_CODE (XEXP (XEXP (y, 0), 1)) == LABEL_REF - && LABEL_REF_LABEL (XEXP (XEXP (y, 0), 1)) == LABEL_REF_LABEL (const_arg1)) + && label_ref_label (XEXP (XEXP (y, 0), 1)) == label_ref_label (const_arg1)) return XEXP (XEXP (y, 0), 0); } @@ -3526,7 +3523,7 @@ fold_rtx (rtx x, rtx_insn *insn) : lookup_as_function (folded_arg1, MINUS); if (y != 0 && GET_CODE (XEXP (y, 1)) == LABEL_REF - && LABEL_REF_LABEL (XEXP (y, 1)) == LABEL_REF_LABEL (const_arg0)) + && label_ref_label (XEXP (y, 1)) == label_ref_label (const_arg0)) return XEXP (y, 0); /* Now try for a CONST of a MINUS like the above. */ @@ -3534,7 +3531,7 @@ fold_rtx (rtx x, rtx_insn *insn) : lookup_as_function (folded_arg1, CONST))) != 0 && GET_CODE (XEXP (y, 0)) == MINUS && GET_CODE (XEXP (XEXP (y, 0), 1)) == LABEL_REF - && LABEL_REF_LABEL (XEXP (XEXP (y, 0), 1)) == LABEL_REF_LABEL (const_arg0)) + && label_ref_label (XEXP (XEXP (y, 0), 1)) == label_ref_label (const_arg0)) return XEXP (XEXP (y, 0), 0); } @@ -3558,7 +3555,7 @@ fold_rtx (rtx x, rtx_insn *insn) instead we test for the problematic value in a more direct manner and hope the Sun compilers get it correct. */ && INTVAL (const_arg1) != - ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT - 1)) + (HOST_WIDE_INT_1 << (HOST_BITS_PER_WIDE_INT - 1)) && REG_P (folded_arg1)) { rtx new_const = GEN_INT (-INTVAL (const_arg1)); @@ -3643,13 +3640,13 @@ fold_rtx (rtx x, rtx_insn *insn) if (code == PLUS && const_arg1 == inner_const && ((HAVE_PRE_INCREMENT - && exact_log2 (INTVAL (const_arg1)) >= 0) + && pow2p_hwi (INTVAL (const_arg1))) || (HAVE_POST_INCREMENT - && exact_log2 (INTVAL (const_arg1)) >= 0) + && pow2p_hwi (INTVAL (const_arg1))) || (HAVE_PRE_DECREMENT - && exact_log2 (- INTVAL (const_arg1)) >= 0) + && pow2p_hwi (- INTVAL (const_arg1))) || (HAVE_POST_DECREMENT - && exact_log2 (- INTVAL (const_arg1)) >= 0))) + && pow2p_hwi (- INTVAL (const_arg1))))) break; /* ??? Vector mode shifts by scalar @@ -4157,10 +4154,10 @@ struct set The size of this field should match the size of the mode field of struct rtx_def (see rtl.h). */ ENUM_BITFIELD(machine_mode) mode : 8; - /* A constant equivalent for SET_SRC, if any. */ - rtx src_const; /* Hash value of constant equivalent for SET_SRC. */ unsigned src_const_hash; + /* A constant equivalent for SET_SRC, if any. */ + rtx src_const; /* Table entry for constant equivalent for SET_SRC, if any. */ struct table_elt *src_const_elt; /* Table entry for the destination address. */ @@ -4298,6 +4295,22 @@ find_sets_in_insn (rtx_insn *insn, struct set **psets) return n_sets; } +/* Subroutine of canonicalize_insn. X is an ASM_OPERANDS in INSN. */ + +static void +canon_asm_operands (rtx x, rtx_insn *insn) +{ + for (int i = ASM_OPERANDS_INPUT_LENGTH (x) - 1; i >= 0; i--) + { + rtx input = ASM_OPERANDS_INPUT (x, i); + if (!(REG_P (input) && HARD_REGISTER_P (input))) + { + input = canon_reg (input, insn); + validate_change (insn, &ASM_OPERANDS_INPUT (x, i), input, 1); + } + } +} + /* Where possible, substitute every register reference in the N_SETS number of SETS in INSN with the canonical register. @@ -4361,17 +4374,7 @@ canonicalize_insn (rtx_insn *insn, struct set **psets, int n_sets) /* Canonicalize a USE of a pseudo register or memory location. */ canon_reg (x, insn); else if (GET_CODE (x) == ASM_OPERANDS) - { - for (i = ASM_OPERANDS_INPUT_LENGTH (x) - 1; i >= 0; i--) - { - rtx input = ASM_OPERANDS_INPUT (x, i); - if (!(REG_P (input) && REGNO (input) < FIRST_PSEUDO_REGISTER)) - { - input = canon_reg (input, insn); - validate_change (insn, &ASM_OPERANDS_INPUT (x, i), input, 1); - } - } - } + canon_asm_operands (x, insn); else if (GET_CODE (x) == CALL) { canon_reg (x, insn); @@ -4400,6 +4403,8 @@ canonicalize_insn (rtx_insn *insn, struct set **psets, int n_sets) && ! (REG_P (XEXP (y, 0)) && REGNO (XEXP (y, 0)) < FIRST_PSEUDO_REGISTER)) canon_reg (y, insn); + else if (GET_CODE (y) == ASM_OPERANDS) + canon_asm_operands (y, insn); else if (GET_CODE (y) == CALL) { canon_reg (y, insn); @@ -4557,9 +4562,9 @@ cse_insn (rtx_insn *insn) else shift = INTVAL (pos); if (INTVAL (width) == HOST_BITS_PER_WIDE_INT) - mask = ~(HOST_WIDE_INT) 0; + mask = HOST_WIDE_INT_M1; else - mask = ((HOST_WIDE_INT) 1 << INTVAL (width)) - 1; + mask = (HOST_WIDE_INT_1 << INTVAL (width)) - 1; val = (val >> shift) & mask; src_eqv = GEN_INT (val); } @@ -4575,6 +4580,7 @@ cse_insn (rtx_insn *insn) for (i = 0; i < n_sets; i++) { bool repeat = false; + bool mem_noop_insn = false; rtx src, dest; rtx src_folded; struct table_elt *elt = 0, *p; @@ -4656,7 +4662,7 @@ cse_insn (rtx_insn *insn) && INTVAL (width) < HOST_BITS_PER_WIDE_INT && (INTVAL (src) & ((HOST_WIDE_INT) (-1) << INTVAL (width)))) src_folded - = GEN_INT (INTVAL (src) & (((HOST_WIDE_INT) 1 + = GEN_INT (INTVAL (src) & ((HOST_WIDE_INT_1 << INTVAL (width)) - 1)); } #endif @@ -4909,11 +4915,10 @@ cse_insn (rtx_insn *insn) also have such operations, but this is only likely to be beneficial on these machines. */ + rtx_code extend_op; if (flag_expensive_optimizations && src_related == 0 - && (GET_MODE_SIZE (mode) < UNITS_PER_WORD) - && GET_MODE_CLASS (mode) == MODE_INT && MEM_P (src) && ! do_not_record - && LOAD_EXTEND_OP (mode) != UNKNOWN) + && (extend_op = load_extend_op (mode)) != UNKNOWN) { struct rtx_def memory_extend_buf; rtx memory_extend_rtx = &memory_extend_buf; @@ -4922,7 +4927,7 @@ cse_insn (rtx_insn *insn) /* Set what we are trying to extend and the operation it might have been extended with. */ memset (memory_extend_rtx, 0, sizeof (*memory_extend_rtx)); - PUT_CODE (memory_extend_rtx, LOAD_EXTEND_OP (mode)); + PUT_CODE (memory_extend_rtx, extend_op); XEXP (memory_extend_rtx, 0) = src; for (tmode = GET_MODE_WIDER_MODE (mode); @@ -5166,7 +5171,7 @@ cse_insn (rtx_insn *insn) } /* Avoid creation of overlapping memory moves. */ - if (MEM_P (trial) && MEM_P (SET_DEST (sets[i].rtl))) + if (MEM_P (trial) && MEM_P (dest) && !rtx_equal_p (trial, dest)) { rtx src, dest; @@ -5224,9 +5229,9 @@ cse_insn (rtx_insn *insn) else shift = INTVAL (pos); if (INTVAL (width) == HOST_BITS_PER_WIDE_INT) - mask = ~(HOST_WIDE_INT) 0; + mask = HOST_WIDE_INT_M1; else - mask = ((HOST_WIDE_INT) 1 << INTVAL (width)) - 1; + mask = (HOST_WIDE_INT_1 << INTVAL (width)) - 1; val &= ~(mask << shift); val |= (INTVAL (trial) & mask) << shift; val = trunc_int_for_mode (val, GET_MODE (dest_reg)); @@ -5277,6 +5282,21 @@ cse_insn (rtx_insn *insn) break; } + /* Similarly, lots of targets don't allow no-op + (set (mem x) (mem x)) moves. */ + else if (n_sets == 1 + && MEM_P (trial) + && MEM_P (dest) + && rtx_equal_p (trial, dest) + && !side_effects_p (dest) + && (cfun->can_delete_dead_exceptions + || insn_nothrow_p (insn))) + { + SET_SRC (sets[i].rtl) = trial; + mem_noop_insn = true; + break; + } + /* Reject certain invalid forms of CONST that we create. */ else if (CONSTANT_P (trial) && GET_CODE (trial) == CONST @@ -5489,12 +5509,22 @@ cse_insn (rtx_insn *insn) else if (n_sets == 1 && dest == pc_rtx && src == pc_rtx) { /* One less use of the label this insn used to jump to. */ - delete_insn_and_edges (insn); + cse_cfg_altered |= delete_insn_and_edges (insn); cse_jumps_altered = true; /* No more processing for this set. */ sets[i].rtl = 0; } + /* Similarly for no-op MEM moves. */ + else if (mem_noop_insn) + { + if (cfun->can_throw_non_call_exceptions && can_throw_internal (insn)) + cse_cfg_altered = true; + cse_cfg_altered |= delete_insn_and_edges (insn); + /* No more processing for this set. */ + sets[i].rtl = 0; + } + /* If this SET is now setting PC to a label, we know it used to be a conditional or computed branch. */ else if (dest == pc_rtx && GET_CODE (src) == LABEL_REF @@ -5525,7 +5555,7 @@ cse_insn (rtx_insn *insn) REG_NOTES (new_rtx) = note; } - delete_insn_and_edges (insn); + cse_cfg_altered |= delete_insn_and_edges (insn); insn = new_rtx; } else @@ -5725,6 +5755,13 @@ cse_insn (rtx_insn *insn) { if (!(RTL_CONST_OR_PURE_CALL_P (insn))) invalidate_memory (); + else + /* For const/pure calls, invalidate any argument slots, because + those are owned by the callee. */ + for (tem = CALL_INSN_FUNCTION_USAGE (insn); tem; tem = XEXP (tem, 1)) + if (GET_CODE (XEXP (tem, 0)) == USE + && MEM_P (XEXP (XEXP (tem, 0), 0))) + invalidate (XEXP (XEXP (tem, 0), 0), VOIDmode); invalidate_for_call (); } @@ -5857,15 +5894,7 @@ cse_insn (rtx_insn *insn) || GET_MODE (dest) == BLKmode /* If we didn't put a REG_EQUAL value or a source into the hash table, there is no point is recording DEST. */ - || sets[i].src_elt == 0 - /* If DEST is a paradoxical SUBREG and SRC is a ZERO_EXTEND - or SIGN_EXTEND, don't record DEST since it can cause - some tracking to be wrong. - - ??? Think about this more later. */ - || (paradoxical_subreg_p (dest) - && (GET_CODE (sets[i].src) == SIGN_EXTEND - || GET_CODE (sets[i].src) == ZERO_EXTEND))) + || sets[i].src_elt == 0) continue; /* STRICT_LOW_PART isn't part of the value BEING set, @@ -5884,6 +5913,11 @@ cse_insn (rtx_insn *insn) sets[i].dest_hash = HASH (dest, GET_MODE (dest)); } + /* If DEST is a paradoxical SUBREG, don't record DEST since the bits + outside the mode of GET_MODE (SUBREG_REG (dest)) are undefined. */ + if (paradoxical_subreg_p (dest)) + continue; + elt = insert (dest, sets[i].src_elt, sets[i].dest_hash, GET_MODE (dest)); @@ -6458,10 +6492,10 @@ check_for_label_ref (rtx_insn *insn) if (GET_CODE (x) == LABEL_REF && !LABEL_REF_NONLOCAL_P (x) && (!JUMP_P (insn) - || !label_is_jump_target_p (LABEL_REF_LABEL (x), insn)) - && LABEL_P (LABEL_REF_LABEL (x)) - && INSN_UID (LABEL_REF_LABEL (x)) != 0 - && !find_reg_note (insn, REG_LABEL_OPERAND, LABEL_REF_LABEL (x))) + || !label_is_jump_target_p (label_ref_label (x), insn)) + && LABEL_P (label_ref_label (x)) + && INSN_UID (label_ref_label (x)) != 0 + && !find_reg_note (insn, REG_LABEL_OPERAND, label_ref_label (x))) return true; } return false; @@ -6643,6 +6677,10 @@ cse_main (rtx_insn *f ATTRIBUTE_UNUSED, int nregs) int *rc_order = XNEWVEC (int, last_basic_block_for_fn (cfun)); int i, n_blocks; + /* CSE doesn't use dominane info but can invalidate it in different ways. + For simplicity free dominance info here. */ + free_dominance_info (CDI_DOMINATORS); + df_set_flags (DF_LR_RUN_DCE); df_note_add_problem (); df_analyze (); @@ -7105,7 +7143,7 @@ delete_trivially_dead_insns (rtx_insn *insns, int nreg) count_reg_usage (insn, counts, NULL_RTX, -1); ndead++; } - delete_insn_and_edges (insn); + cse_cfg_altered |= delete_insn_and_edges (insn); } } @@ -7401,7 +7439,7 @@ cse_cc_succs (basic_block bb, basic_block orig_bb, rtx cc_reg, rtx cc_src, newreg); } - delete_insn_and_edges (insns[i]); + cse_cfg_altered |= delete_insn_and_edges (insns[i]); } return mode; @@ -7536,11 +7574,11 @@ rest_of_handle_cse (void) { timevar_push (TV_JUMP); rebuild_jump_labels (get_insns ()); - cleanup_cfg (CLEANUP_CFG_CHANGED); + cse_cfg_altered |= cleanup_cfg (CLEANUP_CFG_CHANGED); timevar_pop (TV_JUMP); } else if (tem == 1 || optimize > 1) - cleanup_cfg (0); + cse_cfg_altered |= cleanup_cfg (0); return 0; } @@ -7605,11 +7643,11 @@ rest_of_handle_cse2 (void) { timevar_push (TV_JUMP); rebuild_jump_labels (get_insns ()); - cleanup_cfg (CLEANUP_CFG_CHANGED); + cse_cfg_altered |= cleanup_cfg (CLEANUP_CFG_CHANGED); timevar_pop (TV_JUMP); } else if (tem == 1) - cleanup_cfg (0); + cse_cfg_altered |= cleanup_cfg (0); cse_not_expected = 1; return 0; @@ -7669,7 +7707,7 @@ rest_of_handle_cse_after_global_opts (void) rebuild_jump_labels (get_insns ()); tem = cse_main (get_insns (), max_reg_num ()); - purge_all_dead_edges (); + cse_cfg_altered |= purge_all_dead_edges (); delete_trivially_dead_insns (get_insns (), max_reg_num ()); cse_not_expected = !flag_rerun_cse_after_loop; @@ -7679,11 +7717,11 @@ rest_of_handle_cse_after_global_opts (void) { timevar_push (TV_JUMP); rebuild_jump_labels (get_insns ()); - cleanup_cfg (CLEANUP_CFG_CHANGED); + cse_cfg_altered |= cleanup_cfg (CLEANUP_CFG_CHANGED); timevar_pop (TV_JUMP); } else if (tem == 1) - cleanup_cfg (0); + cse_cfg_altered |= cleanup_cfg (0); flag_cse_follow_jumps = save_cfj; return 0; |