X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Ftree-ssa-forwprop.c;h=fe2e89fa918525cae52f8a61cb1c6f605d8f8016;hb=3b01567f28b62f8d753edb3a490064eeeabb5420;hp=b6278045c85849bd96375b8d06d9a2bf8006a01e;hpb=f5d03f2759dd07621697933e41d3d43782f47b14;p=pf3gnuchains%2Fgcc-fork.git diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c index b6278045c85..fe2e89fa918 100644 --- a/gcc/tree-ssa-forwprop.c +++ b/gcc/tree-ssa-forwprop.c @@ -1,5 +1,5 @@ /* Forward propagation of expressions for single use variables. - Copyright (C) 2004, 2005, 2007, 2008, 2009, 2010 + Copyright (C) 2004, 2005, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc. This file is part of GCC. @@ -26,13 +26,14 @@ along with GCC; see the file COPYING3. If not see #include "tm_p.h" #include "basic-block.h" #include "timevar.h" -#include "tree-pretty-print.h" +#include "gimple-pretty-print.h" #include "tree-flow.h" #include "tree-pass.h" #include "tree-dump.h" #include "langhooks.h" #include "flags.h" #include "gimple.h" +#include "expr.h" /* This pass propagates the RHS of assignment statements into use sites of the LHS of the assignment. It's basically a specialized @@ -259,9 +260,6 @@ get_prop_source_stmt (tree name, bool single_use_only, bool *single_use_p) static bool can_propagate_from (gimple def_stmt) { - use_operand_p use_p; - ssa_op_iter iter; - gcc_assert (is_gimple_assign (def_stmt)); /* If the rhs has side-effects we cannot propagate from it. */ @@ -279,9 +277,8 @@ can_propagate_from (gimple def_stmt) return true; /* We cannot propagate ssa names that occur in abnormal phi nodes. */ - FOR_EACH_SSA_USE_OPERAND (use_p, def_stmt, iter, SSA_OP_USE) - if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (USE_FROM_PTR (use_p))) - return false; + if (stmt_references_abnormal_ssa_name (def_stmt)) + return false; /* If the definition is a conversion of a pointer to a function type, then we can not apply optimizations as some targets require @@ -298,34 +295,44 @@ can_propagate_from (gimple def_stmt) return true; } -/* Remove a copy chain ending in NAME along the defs but not - further or including UP_TO_STMT. If NAME was replaced in - its only use then this function can be used to clean up - dead stmts. Returns true if UP_TO_STMT can be removed - as well, otherwise false. */ +/* Remove a chain of dead statements starting at the definition of + NAME. The chain is linked via the first operand of the defining statements. + If NAME was replaced in its only use then this function can be used + to clean up dead stmts. The function handles already released SSA + names gracefully. + Returns true if cleanup-cfg has to run. */ static bool -remove_prop_source_from_use (tree name, gimple up_to_stmt) +remove_prop_source_from_use (tree name) { gimple_stmt_iterator gsi; gimple stmt; + bool cfg_changed = false; do { - if (!has_zero_uses (name)) - return false; + basic_block bb; + + if (SSA_NAME_IN_FREE_LIST (name) + || SSA_NAME_IS_DEFAULT_DEF (name) + || !has_zero_uses (name)) + return cfg_changed; stmt = SSA_NAME_DEF_STMT (name); - if (stmt == up_to_stmt) - return true; + if (gimple_code (stmt) == GIMPLE_PHI + || gimple_has_side_effects (stmt)) + return cfg_changed; + bb = gimple_bb (stmt); gsi = gsi_for_stmt (stmt); - release_defs (stmt); + unlink_stmt_vdef (stmt); gsi_remove (&gsi, true); + release_defs (stmt); + cfg_changed |= gimple_purge_dead_eh_edges (bb); - name = (gimple_assign_copy_p (stmt)) ? gimple_assign_rhs1 (stmt) : NULL; + name = is_gimple_assign (stmt) ? gimple_assign_rhs1 (stmt) : NULL_TREE; } while (name && TREE_CODE (name) == SSA_NAME); - return false; + return cfg_changed; } /* Return the rhs of a gimple_assign STMT in a form of a single tree, @@ -340,7 +347,11 @@ rhs_to_tree (tree type, gimple stmt) { location_t loc = gimple_location (stmt); enum tree_code code = gimple_assign_rhs_code (stmt); - if (get_gimple_rhs_class (code) == GIMPLE_BINARY_RHS) + if (get_gimple_rhs_class (code) == GIMPLE_TERNARY_RHS) + return fold_build3_loc (loc, code, type, gimple_assign_rhs1 (stmt), + gimple_assign_rhs2 (stmt), + gimple_assign_rhs3 (stmt)); + else if (get_gimple_rhs_class (code) == GIMPLE_BINARY_RHS) return fold_build2_loc (loc, code, type, gimple_assign_rhs1 (stmt), gimple_assign_rhs2 (stmt)); else if (get_gimple_rhs_class (code) == GIMPLE_UNARY_RHS) @@ -358,16 +369,20 @@ rhs_to_tree (tree type, gimple stmt) considered simplified. */ static tree -combine_cond_expr_cond (location_t loc, enum tree_code code, tree type, +combine_cond_expr_cond (gimple stmt, enum tree_code code, tree type, tree op0, tree op1, bool invariant_only) { tree t; gcc_assert (TREE_CODE_CLASS (code) == tcc_comparison); - t = fold_binary_loc (loc, code, type, op0, op1); + fold_defer_overflow_warnings (); + t = fold_binary_loc (gimple_location (stmt), code, type, op0, op1); if (!t) - return NULL_TREE; + { + fold_undefer_overflow_warnings (false, NULL, 0); + return NULL_TREE; + } /* Require that we got a boolean type out if we put one in. */ gcc_assert (TREE_CODE (TREE_TYPE (t)) == TREE_CODE (type)); @@ -377,11 +392,103 @@ combine_cond_expr_cond (location_t loc, enum tree_code code, tree type, /* Bail out if we required an invariant but didn't get one. */ if (!t || (invariant_only && !is_gimple_min_invariant (t))) - return NULL_TREE; + { + fold_undefer_overflow_warnings (false, NULL, 0); + return NULL_TREE; + } + + fold_undefer_overflow_warnings (!gimple_no_warning_p (stmt), stmt, 0); return t; } +/* Combine the comparison OP0 CODE OP1 at LOC with the defining statements + of its operand. Return a new comparison tree or NULL_TREE if there + were no simplifying combines. */ + +static tree +forward_propagate_into_comparison_1 (gimple stmt, + enum tree_code code, tree type, + tree op0, tree op1) +{ + tree tmp = NULL_TREE; + tree rhs0 = NULL_TREE, rhs1 = NULL_TREE; + bool single_use0_p = false, single_use1_p = false; + + /* For comparisons use the first operand, that is likely to + simplify comparisons against constants. */ + if (TREE_CODE (op0) == SSA_NAME) + { + gimple def_stmt = get_prop_source_stmt (op0, false, &single_use0_p); + if (def_stmt && can_propagate_from (def_stmt)) + { + rhs0 = rhs_to_tree (TREE_TYPE (op1), def_stmt); + tmp = combine_cond_expr_cond (stmt, code, type, + rhs0, op1, !single_use0_p); + if (tmp) + return tmp; + } + } + + /* If that wasn't successful, try the second operand. */ + if (TREE_CODE (op1) == SSA_NAME) + { + gimple def_stmt = get_prop_source_stmt (op1, false, &single_use1_p); + if (def_stmt && can_propagate_from (def_stmt)) + { + rhs1 = rhs_to_tree (TREE_TYPE (op0), def_stmt); + tmp = combine_cond_expr_cond (stmt, code, type, + op0, rhs1, !single_use1_p); + if (tmp) + return tmp; + } + } + + /* If that wasn't successful either, try both operands. */ + if (rhs0 != NULL_TREE + && rhs1 != NULL_TREE) + tmp = combine_cond_expr_cond (stmt, code, type, + rhs0, rhs1, + !(single_use0_p && single_use1_p)); + + return tmp; +} + +/* Propagate from the ssa name definition statements of the assignment + from a comparison at *GSI into the conditional if that simplifies it. + Returns 1 if the stmt was modified and 2 if the CFG needs cleanup, + otherwise returns 0. */ + +static int +forward_propagate_into_comparison (gimple_stmt_iterator *gsi) +{ + gimple stmt = gsi_stmt (*gsi); + tree tmp; + bool cfg_changed = false; + tree type = TREE_TYPE (gimple_assign_lhs (stmt)); + tree rhs1 = gimple_assign_rhs1 (stmt); + tree rhs2 = gimple_assign_rhs2 (stmt); + + /* Combine the comparison with defining statements. */ + tmp = forward_propagate_into_comparison_1 (stmt, + gimple_assign_rhs_code (stmt), + type, rhs1, rhs2); + if (tmp && useless_type_conversion_p (type, TREE_TYPE (tmp))) + { + gimple_assign_set_rhs_from_tree (gsi, tmp); + fold_stmt (gsi); + update_stmt (gsi_stmt (*gsi)); + + if (TREE_CODE (rhs1) == SSA_NAME) + cfg_changed |= remove_prop_source_from_use (rhs1); + if (TREE_CODE (rhs2) == SSA_NAME) + cfg_changed |= remove_prop_source_from_use (rhs2); + return cfg_changed ? 2 : 1; + } + + return 0; +} + /* Propagate from the ssa name definition statements of COND_EXPR in GIMPLE_COND statement STMT into the conditional if that simplifies it. Returns zero if no statement was changed, one if there were @@ -392,203 +499,137 @@ combine_cond_expr_cond (location_t loc, enum tree_code code, tree type, static int forward_propagate_into_gimple_cond (gimple stmt) { - int did_something = 0; - location_t loc = gimple_location (stmt); - - do { - tree tmp = NULL_TREE; - tree name = NULL_TREE, rhs0 = NULL_TREE, rhs1 = NULL_TREE; - gimple def_stmt; - bool single_use0_p = false, single_use1_p = false; - enum tree_code code = gimple_cond_code (stmt); - - /* We can do tree combining on SSA_NAME and comparison expressions. */ - if (TREE_CODE_CLASS (gimple_cond_code (stmt)) == tcc_comparison) - { - /* For comparisons use the first operand, that is likely to - simplify comparisons against constants. */ - if (TREE_CODE (gimple_cond_lhs (stmt)) == SSA_NAME) - { - name = gimple_cond_lhs (stmt); - def_stmt = get_prop_source_stmt (name, false, &single_use0_p); - if (def_stmt && can_propagate_from (def_stmt)) - { - tree op1 = gimple_cond_rhs (stmt); - rhs0 = rhs_to_tree (TREE_TYPE (op1), def_stmt); - tmp = combine_cond_expr_cond (loc, code, boolean_type_node, - rhs0, op1, !single_use0_p); - } - } - /* If that wasn't successful, try the second operand. */ - if (tmp == NULL_TREE - && TREE_CODE (gimple_cond_rhs (stmt)) == SSA_NAME) - { - tree op0 = gimple_cond_lhs (stmt); - name = gimple_cond_rhs (stmt); - def_stmt = get_prop_source_stmt (name, false, &single_use1_p); - if (!def_stmt || !can_propagate_from (def_stmt)) - return did_something; - - rhs1 = rhs_to_tree (TREE_TYPE (op0), def_stmt); - tmp = combine_cond_expr_cond (loc, code, boolean_type_node, op0, - rhs1, !single_use1_p); - } - /* If that wasn't successful either, try both operands. */ - if (tmp == NULL_TREE - && rhs0 != NULL_TREE - && rhs1 != NULL_TREE) - tmp = combine_cond_expr_cond (loc, code, boolean_type_node, rhs0, - fold_convert_loc (loc, - TREE_TYPE (rhs0), - rhs1), - !(single_use0_p && single_use1_p)); - } - - if (tmp) - { - if (dump_file && tmp) - { - tree cond = build2 (gimple_cond_code (stmt), - boolean_type_node, - gimple_cond_lhs (stmt), - gimple_cond_rhs (stmt)); - fprintf (dump_file, " Replaced '"); - print_generic_expr (dump_file, cond, 0); - fprintf (dump_file, "' with '"); - print_generic_expr (dump_file, tmp, 0); - fprintf (dump_file, "'\n"); - } - - gimple_cond_set_condition_from_tree (stmt, unshare_expr (tmp)); - update_stmt (stmt); - - /* Remove defining statements. */ - remove_prop_source_from_use (name, NULL); + tree tmp; + enum tree_code code = gimple_cond_code (stmt); + bool cfg_changed = false; + tree rhs1 = gimple_cond_lhs (stmt); + tree rhs2 = gimple_cond_rhs (stmt); + + /* We can do tree combining on SSA_NAME and comparison expressions. */ + if (TREE_CODE_CLASS (gimple_cond_code (stmt)) != tcc_comparison) + return 0; + + tmp = forward_propagate_into_comparison_1 (stmt, code, + boolean_type_node, + rhs1, rhs2); + if (tmp) + { + if (dump_file && tmp) + { + fprintf (dump_file, " Replaced '"); + print_gimple_expr (dump_file, stmt, 0, 0); + fprintf (dump_file, "' with '"); + print_generic_expr (dump_file, tmp, 0); + fprintf (dump_file, "'\n"); + } - if (is_gimple_min_invariant (tmp)) - did_something = 2; - else if (did_something == 0) - did_something = 1; + gimple_cond_set_condition_from_tree (stmt, unshare_expr (tmp)); + update_stmt (stmt); - /* Continue combining. */ - continue; - } + if (TREE_CODE (rhs1) == SSA_NAME) + cfg_changed |= remove_prop_source_from_use (rhs1); + if (TREE_CODE (rhs2) == SSA_NAME) + cfg_changed |= remove_prop_source_from_use (rhs2); + return (cfg_changed || is_gimple_min_invariant (tmp)) ? 2 : 1; + } - break; - } while (1); + /* Canonicalize _Bool == 0 and _Bool != 1 to _Bool != 0 by swapping edges. */ + if ((TREE_CODE (TREE_TYPE (rhs1)) == BOOLEAN_TYPE + || (INTEGRAL_TYPE_P (TREE_TYPE (rhs1)) + && TYPE_PRECISION (TREE_TYPE (rhs1)) == 1)) + && ((code == EQ_EXPR + && integer_zerop (rhs2)) + || (code == NE_EXPR + && integer_onep (rhs2)))) + { + basic_block bb = gimple_bb (stmt); + gimple_cond_set_code (stmt, NE_EXPR); + gimple_cond_set_rhs (stmt, build_zero_cst (TREE_TYPE (rhs1))); + EDGE_SUCC (bb, 0)->flags ^= (EDGE_TRUE_VALUE|EDGE_FALSE_VALUE); + EDGE_SUCC (bb, 1)->flags ^= (EDGE_TRUE_VALUE|EDGE_FALSE_VALUE); + return 1; + } - return did_something; + return 0; } /* Propagate from the ssa name definition statements of COND_EXPR in the rhs of statement STMT into the conditional if that simplifies it. - Returns zero if no statement was changed, one if there were - changes and two if cfg_cleanup needs to run. - - This must be kept in sync with forward_propagate_into_gimple_cond. */ + Returns true zero if the stmt was changed. */ -static int +static bool forward_propagate_into_cond (gimple_stmt_iterator *gsi_p) { gimple stmt = gsi_stmt (*gsi_p); - location_t loc = gimple_location (stmt); - int did_something = 0; - - do { - tree tmp = NULL_TREE; - tree cond = gimple_assign_rhs1 (stmt); - tree name, rhs0 = NULL_TREE, rhs1 = NULL_TREE; - gimple def_stmt; - bool single_use0_p = false, single_use1_p = false; - - /* We can do tree combining on SSA_NAME and comparison expressions. */ - if (COMPARISON_CLASS_P (cond) - && TREE_CODE (TREE_OPERAND (cond, 0)) == SSA_NAME) - { - /* For comparisons use the first operand, that is likely to - simplify comparisons against constants. */ - name = TREE_OPERAND (cond, 0); - def_stmt = get_prop_source_stmt (name, false, &single_use0_p); - if (def_stmt && can_propagate_from (def_stmt)) - { - tree op1 = TREE_OPERAND (cond, 1); - rhs0 = rhs_to_tree (TREE_TYPE (op1), def_stmt); - tmp = combine_cond_expr_cond (loc, TREE_CODE (cond), - boolean_type_node, - rhs0, op1, !single_use0_p); - } - /* If that wasn't successful, try the second operand. */ - if (tmp == NULL_TREE - && TREE_CODE (TREE_OPERAND (cond, 1)) == SSA_NAME) - { - tree op0 = TREE_OPERAND (cond, 0); - name = TREE_OPERAND (cond, 1); - def_stmt = get_prop_source_stmt (name, false, &single_use1_p); - if (!def_stmt || !can_propagate_from (def_stmt)) - return did_something; - - rhs1 = rhs_to_tree (TREE_TYPE (op0), def_stmt); - tmp = combine_cond_expr_cond (loc, TREE_CODE (cond), - boolean_type_node, - op0, rhs1, !single_use1_p); - } - /* If that wasn't successful either, try both operands. */ - if (tmp == NULL_TREE - && rhs0 != NULL_TREE - && rhs1 != NULL_TREE) - tmp = combine_cond_expr_cond (loc, TREE_CODE (cond), - boolean_type_node, - rhs0, - fold_convert_loc (loc, - TREE_TYPE (rhs0), - rhs1), - !(single_use0_p && single_use1_p)); - } - else if (TREE_CODE (cond) == SSA_NAME) - { - name = cond; - def_stmt = get_prop_source_stmt (name, true, NULL); - if (def_stmt || !can_propagate_from (def_stmt)) - return did_something; - - rhs0 = gimple_assign_rhs1 (def_stmt); - tmp = combine_cond_expr_cond (loc, NE_EXPR, boolean_type_node, rhs0, - build_int_cst (TREE_TYPE (rhs0), 0), - false); - } - - if (tmp) - { - if (dump_file && tmp) - { - fprintf (dump_file, " Replaced '"); - print_generic_expr (dump_file, cond, 0); - fprintf (dump_file, "' with '"); - print_generic_expr (dump_file, tmp, 0); - fprintf (dump_file, "'\n"); - } - - gimple_assign_set_rhs_from_tree (gsi_p, unshare_expr (tmp)); - stmt = gsi_stmt (*gsi_p); - update_stmt (stmt); - - /* Remove defining statements. */ - remove_prop_source_from_use (name, NULL); + tree tmp = NULL_TREE; + tree cond = gimple_assign_rhs1 (stmt); + bool swap = false; + + /* We can do tree combining on SSA_NAME and comparison expressions. */ + if (COMPARISON_CLASS_P (cond)) + tmp = forward_propagate_into_comparison_1 (stmt, TREE_CODE (cond), + boolean_type_node, + TREE_OPERAND (cond, 0), + TREE_OPERAND (cond, 1)); + else if (TREE_CODE (cond) == SSA_NAME) + { + enum tree_code code; + tree name = cond; + gimple def_stmt = get_prop_source_stmt (name, true, NULL); + if (!def_stmt || !can_propagate_from (def_stmt)) + return 0; + + code = gimple_assign_rhs_code (def_stmt); + if (TREE_CODE_CLASS (code) == tcc_comparison) + tmp = fold_build2_loc (gimple_location (def_stmt), + code, + boolean_type_node, + gimple_assign_rhs1 (def_stmt), + gimple_assign_rhs2 (def_stmt)); + else if ((code == BIT_NOT_EXPR + && TYPE_PRECISION (TREE_TYPE (cond)) == 1) + || (code == BIT_XOR_EXPR + && integer_onep (gimple_assign_rhs2 (def_stmt)))) + { + tmp = gimple_assign_rhs1 (def_stmt); + swap = true; + } + } - if (is_gimple_min_invariant (tmp)) - did_something = 2; - else if (did_something == 0) - did_something = 1; + if (tmp + && is_gimple_condexpr (tmp)) + { + if (dump_file && tmp) + { + fprintf (dump_file, " Replaced '"); + print_generic_expr (dump_file, cond, 0); + fprintf (dump_file, "' with '"); + print_generic_expr (dump_file, tmp, 0); + fprintf (dump_file, "'\n"); + } - /* Continue combining. */ - continue; - } + if (integer_onep (tmp)) + gimple_assign_set_rhs_from_tree (gsi_p, gimple_assign_rhs2 (stmt)); + else if (integer_zerop (tmp)) + gimple_assign_set_rhs_from_tree (gsi_p, gimple_assign_rhs3 (stmt)); + else + { + gimple_assign_set_rhs1 (stmt, unshare_expr (tmp)); + if (swap) + { + tree t = gimple_assign_rhs2 (stmt); + gimple_assign_set_rhs2 (stmt, gimple_assign_rhs3 (stmt)); + gimple_assign_set_rhs3 (stmt, t); + } + } + stmt = gsi_stmt (*gsi_p); + update_stmt (stmt); - break; - } while (1); + return true; + } - return did_something; + return 0; } /* We've just substituted an ADDR_EXPR into stmt. Update all the @@ -723,12 +764,8 @@ forward_propagate_addr_into_variable_array_index (tree offset, } } gimple_assign_set_rhs_from_tree (use_stmt_gsi, new_rhs); - use_stmt = gsi_stmt (*use_stmt_gsi); - - /* That should have created gimple, so there is no need to - record information to undo the propagation. */ - fold_stmt_inplace (use_stmt); - tidy_after_forward_propagate_addr (use_stmt); + fold_stmt (use_stmt_gsi); + tidy_after_forward_propagate_addr (gsi_stmt (*use_stmt_gsi)); return true; } @@ -868,21 +905,21 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, that of the pointed-to type of the address we can put the dereferenced address on the LHS preserving the original alias-type. */ else if (gimple_assign_lhs (use_stmt) == lhs + && integer_zerop (TREE_OPERAND (lhs, 1)) && useless_type_conversion_p (TREE_TYPE (TREE_OPERAND (def_rhs, 0)), TREE_TYPE (gimple_assign_rhs1 (use_stmt)))) { tree *def_rhs_basep = &TREE_OPERAND (def_rhs, 0); - tree new_offset, new_base, saved; + tree new_offset, new_base, saved, new_lhs; while (handled_component_p (*def_rhs_basep)) def_rhs_basep = &TREE_OPERAND (*def_rhs_basep, 0); saved = *def_rhs_basep; if (TREE_CODE (*def_rhs_basep) == MEM_REF) { new_base = TREE_OPERAND (*def_rhs_basep, 0); - new_offset - = int_const_binop (PLUS_EXPR, TREE_OPERAND (lhs, 1), - TREE_OPERAND (*def_rhs_basep, 1), 0); + new_offset = fold_convert (TREE_TYPE (TREE_OPERAND (lhs, 1)), + TREE_OPERAND (*def_rhs_basep, 1)); } else { @@ -891,8 +928,13 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, } *def_rhs_basep = build2 (MEM_REF, TREE_TYPE (*def_rhs_basep), new_base, new_offset); - gimple_assign_set_lhs (use_stmt, - unshare_expr (TREE_OPERAND (def_rhs, 0))); + TREE_THIS_VOLATILE (*def_rhs_basep) = TREE_THIS_VOLATILE (lhs); + TREE_SIDE_EFFECTS (*def_rhs_basep) = TREE_SIDE_EFFECTS (lhs); + TREE_THIS_NOTRAP (*def_rhs_basep) = TREE_THIS_NOTRAP (lhs); + new_lhs = unshare_expr (TREE_OPERAND (def_rhs, 0)); + gimple_assign_set_lhs (use_stmt, new_lhs); + TREE_THIS_VOLATILE (new_lhs) = TREE_THIS_VOLATILE (lhs); + TREE_SIDE_EFFECTS (new_lhs) = TREE_SIDE_EFFECTS (lhs); *def_rhs_basep = saved; tidy_after_forward_propagate_addr (use_stmt); /* Continue propagating into the RHS if this was not the @@ -939,29 +981,29 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, TREE_OPERAND (rhs, 0) = new_ptr; TREE_OPERAND (rhs, 1) = double_int_to_tree (TREE_TYPE (TREE_OPERAND (rhs, 1)), off); - fold_stmt_inplace (use_stmt); + fold_stmt_inplace (use_stmt_gsi); tidy_after_forward_propagate_addr (use_stmt); return res; } - /* If the LHS is a plain dereference and the value type is the same as + /* If the RHS is a plain dereference and the value type is the same as that of the pointed-to type of the address we can put the - dereferenced address on the LHS preserving the original alias-type. */ + dereferenced address on the RHS preserving the original alias-type. */ else if (gimple_assign_rhs1 (use_stmt) == rhs + && integer_zerop (TREE_OPERAND (rhs, 1)) && useless_type_conversion_p (TREE_TYPE (gimple_assign_lhs (use_stmt)), TREE_TYPE (TREE_OPERAND (def_rhs, 0)))) { tree *def_rhs_basep = &TREE_OPERAND (def_rhs, 0); - tree new_offset, new_base, saved; + tree new_offset, new_base, saved, new_rhs; while (handled_component_p (*def_rhs_basep)) def_rhs_basep = &TREE_OPERAND (*def_rhs_basep, 0); saved = *def_rhs_basep; if (TREE_CODE (*def_rhs_basep) == MEM_REF) { new_base = TREE_OPERAND (*def_rhs_basep, 0); - new_offset - = int_const_binop (PLUS_EXPR, TREE_OPERAND (rhs, 1), - TREE_OPERAND (*def_rhs_basep, 1), 0); + new_offset = fold_convert (TREE_TYPE (TREE_OPERAND (rhs, 1)), + TREE_OPERAND (*def_rhs_basep, 1)); } else { @@ -970,10 +1012,15 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, } *def_rhs_basep = build2 (MEM_REF, TREE_TYPE (*def_rhs_basep), new_base, new_offset); - gimple_assign_set_rhs1 (use_stmt, - unshare_expr (TREE_OPERAND (def_rhs, 0))); + TREE_THIS_VOLATILE (*def_rhs_basep) = TREE_THIS_VOLATILE (rhs); + TREE_SIDE_EFFECTS (*def_rhs_basep) = TREE_SIDE_EFFECTS (rhs); + TREE_THIS_NOTRAP (*def_rhs_basep) = TREE_THIS_NOTRAP (rhs); + new_rhs = unshare_expr (TREE_OPERAND (def_rhs, 0)); + gimple_assign_set_rhs1 (use_stmt, new_rhs); + TREE_THIS_VOLATILE (new_rhs) = TREE_THIS_VOLATILE (rhs); + TREE_SIDE_EFFECTS (new_rhs) = TREE_SIDE_EFFECTS (rhs); *def_rhs_basep = saved; - fold_stmt_inplace (use_stmt); + fold_stmt_inplace (use_stmt_gsi); tidy_after_forward_propagate_addr (use_stmt); return res; } @@ -997,31 +1044,21 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, return false; rhs2 = gimple_assign_rhs2 (use_stmt); - /* Try to optimize &x[C1] p+ C2 where C2 is a multiple of the size - of the elements in X into &x[C1 + C2/element size]. */ + /* Optimize &x[C1] p+ C2 to &x p+ C3 with C3 = C1 * element_size + C2. */ if (TREE_CODE (rhs2) == INTEGER_CST) { - tree new_rhs = maybe_fold_stmt_addition (gimple_location (use_stmt), - TREE_TYPE (def_rhs), - def_rhs, rhs2); - if (new_rhs) - { - tree type = TREE_TYPE (gimple_assign_lhs (use_stmt)); - new_rhs = unshare_expr (new_rhs); - if (!useless_type_conversion_p (type, TREE_TYPE (new_rhs))) - { - if (!is_gimple_min_invariant (new_rhs)) - new_rhs = force_gimple_operand_gsi (use_stmt_gsi, new_rhs, - true, NULL_TREE, - true, GSI_SAME_STMT); - new_rhs = fold_convert (type, new_rhs); - } - gimple_assign_set_rhs_from_tree (use_stmt_gsi, new_rhs); - use_stmt = gsi_stmt (*use_stmt_gsi); - update_stmt (use_stmt); - tidy_after_forward_propagate_addr (use_stmt); - return true; - } + tree new_rhs = build1_loc (gimple_location (use_stmt), + ADDR_EXPR, TREE_TYPE (def_rhs), + fold_build2 (MEM_REF, + TREE_TYPE (TREE_TYPE (def_rhs)), + unshare_expr (def_rhs), + fold_convert (ptr_type_node, + rhs2))); + gimple_assign_set_rhs_from_tree (use_stmt_gsi, new_rhs); + use_stmt = gsi_stmt (*use_stmt_gsi); + update_stmt (use_stmt); + tidy_after_forward_propagate_addr (use_stmt); + return true; } /* Try to optimize &x[0] p+ OFFSET where OFFSET is defined by @@ -1109,9 +1146,10 @@ forward_propagate_addr_expr (tree name, tree rhs) } } - return all; + return all && has_zero_uses (name); } + /* Forward propagate the comparison defined in STMT like cond_1 = x CMP y to uses of the form a_1 = (T')cond_1 @@ -1125,6 +1163,9 @@ forward_propagate_comparison (gimple stmt) tree name = gimple_assign_lhs (stmt); gimple use_stmt; tree tmp = NULL_TREE; + gimple_stmt_iterator gsi; + enum tree_code code; + tree lhs; /* Don't propagate ssa names that occur in abnormal phis. */ if ((TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME @@ -1135,93 +1176,54 @@ forward_propagate_comparison (gimple stmt) /* Do not un-cse comparisons. But propagate through copies. */ use_stmt = get_prop_dest_stmt (name, &name); - if (!use_stmt) + if (!use_stmt + || !is_gimple_assign (use_stmt)) return false; - /* Conversion of the condition result to another integral type. */ - if (is_gimple_assign (use_stmt) - && (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (use_stmt)) - || TREE_CODE_CLASS (gimple_assign_rhs_code (use_stmt)) - == tcc_comparison - || gimple_assign_rhs_code (use_stmt) == TRUTH_NOT_EXPR) - && INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (use_stmt)))) - { - tree lhs = gimple_assign_lhs (use_stmt); - - /* We can propagate the condition into a conversion. */ - if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (use_stmt))) - { - /* Avoid using fold here as that may create a COND_EXPR with - non-boolean condition as canonical form. */ - tmp = build2 (gimple_assign_rhs_code (stmt), TREE_TYPE (lhs), - gimple_assign_rhs1 (stmt), gimple_assign_rhs2 (stmt)); - } - /* We can propagate the condition into X op CST where op - is EQ_EXPR or NE_EXPR and CST is either one or zero. */ - else if (TREE_CODE_CLASS (gimple_assign_rhs_code (use_stmt)) - == tcc_comparison - && TREE_CODE (gimple_assign_rhs1 (use_stmt)) == SSA_NAME - && TREE_CODE (gimple_assign_rhs2 (use_stmt)) == INTEGER_CST) - { - enum tree_code code = gimple_assign_rhs_code (use_stmt); - tree cst = gimple_assign_rhs2 (use_stmt); - tree cond; - - cond = build2 (gimple_assign_rhs_code (stmt), - TREE_TYPE (cst), - gimple_assign_rhs1 (stmt), - gimple_assign_rhs2 (stmt)); - - tmp = combine_cond_expr_cond (gimple_location (use_stmt), - code, TREE_TYPE (lhs), - cond, cst, false); - if (tmp == NULL_TREE) - return false; - } - /* We can propagate the condition into a statement that - computes the logical negation of the comparison result. */ - else if (gimple_assign_rhs_code (use_stmt) == TRUTH_NOT_EXPR) - { - tree type = TREE_TYPE (gimple_assign_rhs1 (stmt)); - bool nans = HONOR_NANS (TYPE_MODE (type)); - enum tree_code code; - code = invert_tree_comparison (gimple_assign_rhs_code (stmt), nans); - if (code == ERROR_MARK) - return false; + code = gimple_assign_rhs_code (use_stmt); + lhs = gimple_assign_lhs (use_stmt); + if (!INTEGRAL_TYPE_P (TREE_TYPE (lhs))) + return false; - tmp = build2 (code, TREE_TYPE (lhs), gimple_assign_rhs1 (stmt), - gimple_assign_rhs2 (stmt)); - } - else + /* We can propagate the condition into a statement that + computes the logical negation of the comparison result. */ + if ((code == BIT_NOT_EXPR + && TYPE_PRECISION (TREE_TYPE (lhs)) == 1) + || (code == BIT_XOR_EXPR + && integer_onep (gimple_assign_rhs2 (use_stmt)))) + { + tree type = TREE_TYPE (gimple_assign_rhs1 (stmt)); + bool nans = HONOR_NANS (TYPE_MODE (type)); + enum tree_code inv_code; + inv_code = invert_tree_comparison (gimple_assign_rhs_code (stmt), nans); + if (inv_code == ERROR_MARK) return false; - { - gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt); - gimple_assign_set_rhs_from_tree (&gsi, unshare_expr (tmp)); - use_stmt = gsi_stmt (gsi); - update_stmt (use_stmt); - } + tmp = build2 (inv_code, TREE_TYPE (lhs), gimple_assign_rhs1 (stmt), + gimple_assign_rhs2 (stmt)); + } + else + return false; - /* Remove defining statements. */ - remove_prop_source_from_use (name, stmt); + gsi = gsi_for_stmt (use_stmt); + gimple_assign_set_rhs_from_tree (&gsi, unshare_expr (tmp)); + use_stmt = gsi_stmt (gsi); + update_stmt (use_stmt); - if (dump_file && (dump_flags & TDF_DETAILS)) - { - tree old_rhs = rhs_to_tree (TREE_TYPE (gimple_assign_lhs (stmt)), - stmt); - fprintf (dump_file, " Replaced '"); - print_generic_expr (dump_file, old_rhs, dump_flags); - fprintf (dump_file, "' with '"); - print_generic_expr (dump_file, tmp, dump_flags); - fprintf (dump_file, "'\n"); - } - - return true; + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, " Replaced '"); + print_gimple_expr (dump_file, stmt, 0, dump_flags); + fprintf (dump_file, "' with '"); + print_gimple_expr (dump_file, use_stmt, 0, dump_flags); + fprintf (dump_file, "'\n"); } - return false; + /* Remove defining statements. */ + return remove_prop_source_from_use (name); } + /* If we have lhs = ~x (STMT), look and see if earlier we had x = ~y. If so, we can change STMT into lhs = y which can later be copy propagated. Similarly for negation. @@ -1234,9 +1236,11 @@ forward_propagate_comparison (gimple stmt) there's less work to do for each NOT/NEG expression we find. Backwards propagation needs to look at the statement in a single backlink. Forward propagation needs to look at potentially more - than one forward link. */ + than one forward link. -static void + Returns true when the statement was changed. */ + +static bool simplify_not_neg_expr (gimple_stmt_iterator *gsi_p) { gimple stmt = gsi_stmt (*gsi_p); @@ -1256,14 +1260,17 @@ simplify_not_neg_expr (gimple_stmt_iterator *gsi_p) gimple_assign_set_rhs_from_tree (gsi_p, rhs_def_operand); stmt = gsi_stmt (*gsi_p); update_stmt (stmt); + return true; } } + + return false; } /* STMT is a SWITCH_EXPR for which we attempt to find equivalent forms of the condition which we may be able to optimize better. */ -static void +static bool simplify_gimple_switch (gimple stmt) { tree cond = gimple_switch_index (stmt); @@ -1285,10 +1292,8 @@ simplify_gimple_switch (gimple stmt) def = gimple_assign_rhs1 (def_stmt); -#ifdef ENABLE_CHECKING /* ??? Why was Jeff testing this? We are gimple... */ - gcc_assert (is_gimple_val (def)); -#endif + gcc_checking_assert (is_gimple_val (def)); to = TREE_TYPE (cond); ti = TREE_TYPE (def); @@ -1311,56 +1316,1052 @@ simplify_gimple_switch (gimple stmt) { gimple_switch_set_index (stmt, def); update_stmt (stmt); + return true; } } } } + + return false; } -/* Run bitwise and assignments throug the folder. If the first argument is an - ssa name that is itself a result of a typecast of an ADDR_EXPR to an - integer, feed the ADDR_EXPR to the folder rather than the ssa name. -*/ +/* For pointers p2 and p1 return p2 - p1 if the + difference is known and constant, otherwise return NULL. */ -static void -simplify_bitwise_and (gimple_stmt_iterator *gsi, gimple stmt) +static tree +constant_pointer_difference (tree p1, tree p2) { - tree res; + int i, j; +#define CPD_ITERATIONS 5 + tree exps[2][CPD_ITERATIONS]; + tree offs[2][CPD_ITERATIONS]; + int cnt[2]; + + for (i = 0; i < 2; i++) + { + tree p = i ? p1 : p2; + tree off = size_zero_node; + gimple stmt; + enum tree_code code; + + /* For each of p1 and p2 we need to iterate at least + twice, to handle ADDR_EXPR directly in p1/p2, + SSA_NAME with ADDR_EXPR or POINTER_PLUS_EXPR etc. + on definition's stmt RHS. Iterate a few extra times. */ + j = 0; + do + { + if (!POINTER_TYPE_P (TREE_TYPE (p))) + break; + if (TREE_CODE (p) == ADDR_EXPR) + { + tree q = TREE_OPERAND (p, 0); + HOST_WIDE_INT offset; + tree base = get_addr_base_and_unit_offset (q, &offset); + if (base) + { + q = base; + if (offset) + off = size_binop (PLUS_EXPR, off, size_int (offset)); + } + if (TREE_CODE (q) == MEM_REF + && TREE_CODE (TREE_OPERAND (q, 0)) == SSA_NAME) + { + p = TREE_OPERAND (q, 0); + off = size_binop (PLUS_EXPR, off, + double_int_to_tree (sizetype, + mem_ref_offset (q))); + } + else + { + exps[i][j] = q; + offs[i][j++] = off; + break; + } + } + if (TREE_CODE (p) != SSA_NAME) + break; + exps[i][j] = p; + offs[i][j++] = off; + if (j == CPD_ITERATIONS) + break; + stmt = SSA_NAME_DEF_STMT (p); + if (!is_gimple_assign (stmt) || gimple_assign_lhs (stmt) != p) + break; + code = gimple_assign_rhs_code (stmt); + if (code == POINTER_PLUS_EXPR) + { + if (TREE_CODE (gimple_assign_rhs2 (stmt)) != INTEGER_CST) + break; + off = size_binop (PLUS_EXPR, off, gimple_assign_rhs2 (stmt)); + p = gimple_assign_rhs1 (stmt); + } + else if (code == ADDR_EXPR || code == NOP_EXPR) + p = gimple_assign_rhs1 (stmt); + else + break; + } + while (1); + cnt[i] = j; + } + + for (i = 0; i < cnt[0]; i++) + for (j = 0; j < cnt[1]; j++) + if (exps[0][i] == exps[1][j]) + return size_binop (MINUS_EXPR, offs[0][i], offs[1][j]); + + return NULL_TREE; +} + +/* *GSI_P is a GIMPLE_CALL to a builtin function. + Optimize + memcpy (p, "abcd", 4); + memset (p + 4, ' ', 3); + into + memcpy (p, "abcd ", 7); + call if the latter can be stored by pieces during expansion. */ + +static bool +simplify_builtin_call (gimple_stmt_iterator *gsi_p, tree callee2) +{ + gimple stmt1, stmt2 = gsi_stmt (*gsi_p); + tree vuse = gimple_vuse (stmt2); + if (vuse == NULL) + return false; + stmt1 = SSA_NAME_DEF_STMT (vuse); + + switch (DECL_FUNCTION_CODE (callee2)) + { + case BUILT_IN_MEMSET: + if (gimple_call_num_args (stmt2) != 3 + || gimple_call_lhs (stmt2) + || CHAR_BIT != 8 + || BITS_PER_UNIT != 8) + break; + else + { + tree callee1; + tree ptr1, src1, str1, off1, len1, lhs1; + tree ptr2 = gimple_call_arg (stmt2, 0); + tree val2 = gimple_call_arg (stmt2, 1); + tree len2 = gimple_call_arg (stmt2, 2); + tree diff, vdef, new_str_cst; + gimple use_stmt; + unsigned int ptr1_align; + unsigned HOST_WIDE_INT src_len; + char *src_buf; + use_operand_p use_p; + + if (!host_integerp (val2, 0) + || !host_integerp (len2, 1)) + break; + if (is_gimple_call (stmt1)) + { + /* If first stmt is a call, it needs to be memcpy + or mempcpy, with string literal as second argument and + constant length. */ + callee1 = gimple_call_fndecl (stmt1); + if (callee1 == NULL_TREE + || DECL_BUILT_IN_CLASS (callee1) != BUILT_IN_NORMAL + || gimple_call_num_args (stmt1) != 3) + break; + if (DECL_FUNCTION_CODE (callee1) != BUILT_IN_MEMCPY + && DECL_FUNCTION_CODE (callee1) != BUILT_IN_MEMPCPY) + break; + ptr1 = gimple_call_arg (stmt1, 0); + src1 = gimple_call_arg (stmt1, 1); + len1 = gimple_call_arg (stmt1, 2); + lhs1 = gimple_call_lhs (stmt1); + if (!host_integerp (len1, 1)) + break; + str1 = string_constant (src1, &off1); + if (str1 == NULL_TREE) + break; + if (!host_integerp (off1, 1) + || compare_tree_int (off1, TREE_STRING_LENGTH (str1) - 1) > 0 + || compare_tree_int (len1, TREE_STRING_LENGTH (str1) + - tree_low_cst (off1, 1)) > 0 + || TREE_CODE (TREE_TYPE (str1)) != ARRAY_TYPE + || TYPE_MODE (TREE_TYPE (TREE_TYPE (str1))) + != TYPE_MODE (char_type_node)) + break; + } + else if (gimple_assign_single_p (stmt1)) + { + /* Otherwise look for length 1 memcpy optimized into + assignment. */ + ptr1 = gimple_assign_lhs (stmt1); + src1 = gimple_assign_rhs1 (stmt1); + if (TREE_CODE (ptr1) != MEM_REF + || TYPE_MODE (TREE_TYPE (ptr1)) != TYPE_MODE (char_type_node) + || !host_integerp (src1, 0)) + break; + ptr1 = build_fold_addr_expr (ptr1); + callee1 = NULL_TREE; + len1 = size_one_node; + lhs1 = NULL_TREE; + off1 = size_zero_node; + str1 = NULL_TREE; + } + else + break; + + diff = constant_pointer_difference (ptr1, ptr2); + if (diff == NULL && lhs1 != NULL) + { + diff = constant_pointer_difference (lhs1, ptr2); + if (DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY + && diff != NULL) + diff = size_binop (PLUS_EXPR, diff, + fold_convert (sizetype, len1)); + } + /* If the difference between the second and first destination pointer + is not constant, or is bigger than memcpy length, bail out. */ + if (diff == NULL + || !host_integerp (diff, 1) + || tree_int_cst_lt (len1, diff)) + break; + + /* Use maximum of difference plus memset length and memcpy length + as the new memcpy length, if it is too big, bail out. */ + src_len = tree_low_cst (diff, 1); + src_len += tree_low_cst (len2, 1); + if (src_len < (unsigned HOST_WIDE_INT) tree_low_cst (len1, 1)) + src_len = tree_low_cst (len1, 1); + if (src_len > 1024) + break; + + /* If mempcpy value is used elsewhere, bail out, as mempcpy + with bigger length will return different result. */ + if (lhs1 != NULL_TREE + && DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY + && (TREE_CODE (lhs1) != SSA_NAME + || !single_imm_use (lhs1, &use_p, &use_stmt) + || use_stmt != stmt2)) + break; + + /* If anything reads memory in between memcpy and memset + call, the modified memcpy call might change it. */ + vdef = gimple_vdef (stmt1); + if (vdef != NULL + && (!single_imm_use (vdef, &use_p, &use_stmt) + || use_stmt != stmt2)) + break; + + ptr1_align = get_pointer_alignment (ptr1); + /* Construct the new source string literal. */ + src_buf = XALLOCAVEC (char, src_len + 1); + if (callee1) + memcpy (src_buf, + TREE_STRING_POINTER (str1) + tree_low_cst (off1, 1), + tree_low_cst (len1, 1)); + else + src_buf[0] = tree_low_cst (src1, 0); + memset (src_buf + tree_low_cst (diff, 1), + tree_low_cst (val2, 1), tree_low_cst (len2, 1)); + src_buf[src_len] = '\0'; + /* Neither builtin_strncpy_read_str nor builtin_memcpy_read_str + handle embedded '\0's. */ + if (strlen (src_buf) != src_len) + break; + rtl_profile_for_bb (gimple_bb (stmt2)); + /* If the new memcpy wouldn't be emitted by storing the literal + by pieces, this optimization might enlarge .rodata too much, + as commonly used string literals couldn't be shared any + longer. */ + if (!can_store_by_pieces (src_len, + builtin_strncpy_read_str, + src_buf, ptr1_align, false)) + break; + + new_str_cst = build_string_literal (src_len, src_buf); + if (callee1) + { + /* If STMT1 is a mem{,p}cpy call, adjust it and remove + memset call. */ + if (lhs1 && DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY) + gimple_call_set_lhs (stmt1, NULL_TREE); + gimple_call_set_arg (stmt1, 1, new_str_cst); + gimple_call_set_arg (stmt1, 2, + build_int_cst (TREE_TYPE (len1), src_len)); + update_stmt (stmt1); + unlink_stmt_vdef (stmt2); + gsi_remove (gsi_p, true); + release_defs (stmt2); + if (lhs1 && DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY) + release_ssa_name (lhs1); + return true; + } + else + { + /* Otherwise, if STMT1 is length 1 memcpy optimized into + assignment, remove STMT1 and change memset call into + memcpy call. */ + gimple_stmt_iterator gsi = gsi_for_stmt (stmt1); + + if (!is_gimple_val (ptr1)) + ptr1 = force_gimple_operand_gsi (gsi_p, ptr1, true, NULL_TREE, + true, GSI_SAME_STMT); + gimple_call_set_fndecl (stmt2, + builtin_decl_explicit (BUILT_IN_MEMCPY)); + gimple_call_set_arg (stmt2, 0, ptr1); + gimple_call_set_arg (stmt2, 1, new_str_cst); + gimple_call_set_arg (stmt2, 2, + build_int_cst (TREE_TYPE (len2), src_len)); + unlink_stmt_vdef (stmt1); + gsi_remove (&gsi, true); + release_defs (stmt1); + update_stmt (stmt2); + return false; + } + } + break; + default: + break; + } + return false; +} + +/* Checks if expression has type of one-bit precision, or is a known + truth-valued expression. */ +static bool +truth_valued_ssa_name (tree name) +{ + gimple def; + tree type = TREE_TYPE (name); + + if (!INTEGRAL_TYPE_P (type)) + return false; + /* Don't check here for BOOLEAN_TYPE as the precision isn't + necessarily one and so ~X is not equal to !X. */ + if (TYPE_PRECISION (type) == 1) + return true; + def = SSA_NAME_DEF_STMT (name); + if (is_gimple_assign (def)) + return truth_value_p (gimple_assign_rhs_code (def)); + return false; +} + +/* Helper routine for simplify_bitwise_binary_1 function. + Return for the SSA name NAME the expression X if it mets condition + NAME = !X. Otherwise return NULL_TREE. + Detected patterns for NAME = !X are: + !X and X == 0 for X with integral type. + X ^ 1, X != 1,or ~X for X with integral type with precision of one. */ +static tree +lookup_logical_inverted_value (tree name) +{ + tree op1, op2; + enum tree_code code; + gimple def; + + /* If name has none-intergal type, or isn't a SSA_NAME, then + return. */ + if (TREE_CODE (name) != SSA_NAME + || !INTEGRAL_TYPE_P (TREE_TYPE (name))) + return NULL_TREE; + def = SSA_NAME_DEF_STMT (name); + if (!is_gimple_assign (def)) + return NULL_TREE; + + code = gimple_assign_rhs_code (def); + op1 = gimple_assign_rhs1 (def); + op2 = NULL_TREE; + + /* Get for EQ_EXPR or BIT_XOR_EXPR operation the second operand. + If CODE isn't an EQ_EXPR, BIT_XOR_EXPR, or BIT_NOT_EXPR, then return. */ + if (code == EQ_EXPR || code == NE_EXPR + || code == BIT_XOR_EXPR) + op2 = gimple_assign_rhs2 (def); + + switch (code) + { + case BIT_NOT_EXPR: + if (truth_valued_ssa_name (name)) + return op1; + break; + case EQ_EXPR: + /* Check if we have X == 0 and X has an integral type. */ + if (!INTEGRAL_TYPE_P (TREE_TYPE (op1))) + break; + if (integer_zerop (op2)) + return op1; + break; + case NE_EXPR: + /* Check if we have X != 1 and X is a truth-valued. */ + if (!INTEGRAL_TYPE_P (TREE_TYPE (op1))) + break; + if (integer_onep (op2) && truth_valued_ssa_name (op1)) + return op1; + break; + case BIT_XOR_EXPR: + /* Check if we have X ^ 1 and X is truth valued. */ + if (integer_onep (op2) && truth_valued_ssa_name (op1)) + return op1; + break; + default: + break; + } + + return NULL_TREE; +} + +/* Optimize ARG1 CODE ARG2 to a constant for bitwise binary + operations CODE, if one operand has the logically inverted + value of the other. */ +static tree +simplify_bitwise_binary_1 (enum tree_code code, tree type, + tree arg1, tree arg2) +{ + tree anot; + + /* If CODE isn't a bitwise binary operation, return NULL_TREE. */ + if (code != BIT_AND_EXPR && code != BIT_IOR_EXPR + && code != BIT_XOR_EXPR) + return NULL_TREE; + + /* First check if operands ARG1 and ARG2 are equal. If so + return NULL_TREE as this optimization is handled fold_stmt. */ + if (arg1 == arg2) + return NULL_TREE; + /* See if we have in arguments logical-not patterns. */ + if (((anot = lookup_logical_inverted_value (arg1)) == NULL_TREE + || anot != arg2) + && ((anot = lookup_logical_inverted_value (arg2)) == NULL_TREE + || anot != arg1)) + return NULL_TREE; + + /* X & !X -> 0. */ + if (code == BIT_AND_EXPR) + return fold_convert (type, integer_zero_node); + /* X | !X -> 1 and X ^ !X -> 1, if X is truth-valued. */ + if (truth_valued_ssa_name (anot)) + return fold_convert (type, integer_one_node); + + /* ??? Otherwise result is (X != 0 ? X : 1). not handled. */ + return NULL_TREE; +} + +/* Simplify bitwise binary operations. + Return true if a transformation applied, otherwise return false. */ + +static bool +simplify_bitwise_binary (gimple_stmt_iterator *gsi) +{ + gimple stmt = gsi_stmt (*gsi); tree arg1 = gimple_assign_rhs1 (stmt); tree arg2 = gimple_assign_rhs2 (stmt); + enum tree_code code = gimple_assign_rhs_code (stmt); + tree res; + gimple def1 = NULL, def2 = NULL; + tree def1_arg1, def2_arg1; + enum tree_code def1_code, def2_code; - if (TREE_CODE (arg2) != INTEGER_CST) - return; - - if (TREE_CODE (arg1) == SSA_NAME && !SSA_NAME_IS_DEFAULT_DEF (arg1)) + def1_code = TREE_CODE (arg1); + def1_arg1 = arg1; + if (TREE_CODE (arg1) == SSA_NAME) { - gimple def = SSA_NAME_DEF_STMT (arg1); + def1 = SSA_NAME_DEF_STMT (arg1); + if (is_gimple_assign (def1)) + { + def1_code = gimple_assign_rhs_code (def1); + def1_arg1 = gimple_assign_rhs1 (def1); + } + } - if (gimple_assign_cast_p (def) - && INTEGRAL_TYPE_P (gimple_expr_type (def))) + def2_code = TREE_CODE (arg2); + def2_arg1 = arg2; + if (TREE_CODE (arg2) == SSA_NAME) + { + def2 = SSA_NAME_DEF_STMT (arg2); + if (is_gimple_assign (def2)) { - tree op = gimple_assign_rhs1 (def); + def2_code = gimple_assign_rhs_code (def2); + def2_arg1 = gimple_assign_rhs1 (def2); + } + } - if (TREE_CODE (op) == ADDR_EXPR) - arg1 = op; + /* Try to fold (type) X op CST -> (type) (X op ((type-x) CST)). */ + if (TREE_CODE (arg2) == INTEGER_CST + && CONVERT_EXPR_CODE_P (def1_code) + && INTEGRAL_TYPE_P (TREE_TYPE (def1_arg1)) + && int_fits_type_p (arg2, TREE_TYPE (def1_arg1))) + { + gimple newop; + tree tem = create_tmp_reg (TREE_TYPE (def1_arg1), NULL); + newop = + gimple_build_assign_with_ops (code, tem, def1_arg1, + fold_convert_loc (gimple_location (stmt), + TREE_TYPE (def1_arg1), + arg2)); + tem = make_ssa_name (tem, newop); + gimple_assign_set_lhs (newop, tem); + gimple_set_location (newop, gimple_location (stmt)); + gsi_insert_before (gsi, newop, GSI_SAME_STMT); + gimple_assign_set_rhs_with_ops_1 (gsi, NOP_EXPR, + tem, NULL_TREE, NULL_TREE); + update_stmt (gsi_stmt (*gsi)); + return true; + } + + /* For bitwise binary operations apply operand conversions to the + binary operation result instead of to the operands. This allows + to combine successive conversions and bitwise binary operations. */ + if (CONVERT_EXPR_CODE_P (def1_code) + && CONVERT_EXPR_CODE_P (def2_code) + && types_compatible_p (TREE_TYPE (def1_arg1), TREE_TYPE (def2_arg1)) + /* Make sure that the conversion widens the operands, or has same + precision, or that it changes the operation to a bitfield + precision. */ + && ((TYPE_PRECISION (TREE_TYPE (def1_arg1)) + <= TYPE_PRECISION (TREE_TYPE (arg1))) + || (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (arg1))) + != MODE_INT) + || (TYPE_PRECISION (TREE_TYPE (arg1)) + != GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (arg1)))))) + { + gimple newop; + tree tem = create_tmp_reg (TREE_TYPE (def1_arg1), + NULL); + newop = gimple_build_assign_with_ops (code, tem, def1_arg1, def2_arg1); + tem = make_ssa_name (tem, newop); + gimple_assign_set_lhs (newop, tem); + gimple_set_location (newop, gimple_location (stmt)); + gsi_insert_before (gsi, newop, GSI_SAME_STMT); + gimple_assign_set_rhs_with_ops_1 (gsi, NOP_EXPR, + tem, NULL_TREE, NULL_TREE); + update_stmt (gsi_stmt (*gsi)); + return true; + } + + /* (a | CST1) & CST2 -> (a & CST2) | (CST1 & CST2). */ + if (code == BIT_AND_EXPR + && def1_code == BIT_IOR_EXPR + && TREE_CODE (arg2) == INTEGER_CST + && TREE_CODE (gimple_assign_rhs2 (def1)) == INTEGER_CST) + { + tree cst = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg2), + arg2, gimple_assign_rhs2 (def1)); + tree tem; + gimple newop; + if (integer_zerop (cst)) + { + gimple_assign_set_rhs1 (stmt, def1_arg1); + update_stmt (stmt); + return true; } + tem = create_tmp_reg (TREE_TYPE (arg2), NULL); + newop = gimple_build_assign_with_ops (BIT_AND_EXPR, + tem, def1_arg1, arg2); + tem = make_ssa_name (tem, newop); + gimple_assign_set_lhs (newop, tem); + gimple_set_location (newop, gimple_location (stmt)); + /* Make sure to re-process the new stmt as it's walking upwards. */ + gsi_insert_before (gsi, newop, GSI_NEW_STMT); + gimple_assign_set_rhs1 (stmt, tem); + gimple_assign_set_rhs2 (stmt, cst); + gimple_assign_set_rhs_code (stmt, BIT_IOR_EXPR); + update_stmt (stmt); + return true; } - res = fold_binary_loc (gimple_location (stmt), - BIT_AND_EXPR, TREE_TYPE (gimple_assign_lhs (stmt)), - arg1, arg2); - if (res && is_gimple_min_invariant (res)) + /* Combine successive equal operations with constants. */ + if ((code == BIT_AND_EXPR + || code == BIT_IOR_EXPR + || code == BIT_XOR_EXPR) + && def1_code == code + && TREE_CODE (arg2) == INTEGER_CST + && TREE_CODE (gimple_assign_rhs2 (def1)) == INTEGER_CST) + { + tree cst = fold_build2 (code, TREE_TYPE (arg2), + arg2, gimple_assign_rhs2 (def1)); + gimple_assign_set_rhs1 (stmt, def1_arg1); + gimple_assign_set_rhs2 (stmt, cst); + update_stmt (stmt); + return true; + } + + /* Canonicalize X ^ ~0 to ~X. */ + if (code == BIT_XOR_EXPR + && TREE_CODE (arg2) == INTEGER_CST + && integer_all_onesp (arg2)) + { + gimple_assign_set_rhs_with_ops (gsi, BIT_NOT_EXPR, arg1, NULL_TREE); + gcc_assert (gsi_stmt (*gsi) == stmt); + update_stmt (stmt); + return true; + } + + /* Try simple folding for X op !X, and X op X. */ + res = simplify_bitwise_binary_1 (code, TREE_TYPE (arg1), arg1, arg2); + if (res != NULL_TREE) { gimple_assign_set_rhs_from_tree (gsi, res); + update_stmt (gsi_stmt (*gsi)); + return true; + } + + return false; +} + + +/* Perform re-associations of the plus or minus statement STMT that are + always permitted. Returns true if the CFG was changed. */ + +static bool +associate_plusminus (gimple_stmt_iterator *gsi) +{ + gimple stmt = gsi_stmt (*gsi); + tree rhs1 = gimple_assign_rhs1 (stmt); + tree rhs2 = gimple_assign_rhs2 (stmt); + enum tree_code code = gimple_assign_rhs_code (stmt); + bool changed; + + /* We can't reassociate at all for saturating types. */ + if (TYPE_SATURATING (TREE_TYPE (rhs1))) + return false; + + /* First contract negates. */ + do + { + changed = false; + + /* A +- (-B) -> A -+ B. */ + if (TREE_CODE (rhs2) == SSA_NAME) + { + gimple def_stmt = SSA_NAME_DEF_STMT (rhs2); + if (is_gimple_assign (def_stmt) + && gimple_assign_rhs_code (def_stmt) == NEGATE_EXPR + && can_propagate_from (def_stmt)) + { + code = (code == MINUS_EXPR) ? PLUS_EXPR : MINUS_EXPR; + gimple_assign_set_rhs_code (stmt, code); + rhs2 = gimple_assign_rhs1 (def_stmt); + gimple_assign_set_rhs2 (stmt, rhs2); + gimple_set_modified (stmt, true); + changed = true; + } + } + + /* (-A) + B -> B - A. */ + if (TREE_CODE (rhs1) == SSA_NAME + && code == PLUS_EXPR) + { + gimple def_stmt = SSA_NAME_DEF_STMT (rhs1); + if (is_gimple_assign (def_stmt) + && gimple_assign_rhs_code (def_stmt) == NEGATE_EXPR + && can_propagate_from (def_stmt)) + { + code = MINUS_EXPR; + gimple_assign_set_rhs_code (stmt, code); + rhs1 = rhs2; + gimple_assign_set_rhs1 (stmt, rhs1); + rhs2 = gimple_assign_rhs1 (def_stmt); + gimple_assign_set_rhs2 (stmt, rhs2); + gimple_set_modified (stmt, true); + changed = true; + } + } + } + while (changed); + + /* We can't reassociate floating-point or fixed-point plus or minus + because of saturation to +-Inf. */ + if (FLOAT_TYPE_P (TREE_TYPE (rhs1)) + || FIXED_POINT_TYPE_P (TREE_TYPE (rhs1))) + goto out; + + /* Second match patterns that allow contracting a plus-minus pair + irrespective of overflow issues. + + (A +- B) - A -> +- B + (A +- B) -+ B -> A + (CST +- A) +- CST -> CST +- A + (A + CST) +- CST -> A + CST + ~A + A -> -1 + ~A + 1 -> -A + A - (A +- B) -> -+ B + A +- (B +- A) -> +- B + CST +- (CST +- A) -> CST +- A + CST +- (A +- CST) -> CST +- A + A + ~A -> -1 + + via commutating the addition and contracting operations to zero + by reassociation. */ + + if (TREE_CODE (rhs1) == SSA_NAME) + { + gimple def_stmt = SSA_NAME_DEF_STMT (rhs1); + if (is_gimple_assign (def_stmt) && can_propagate_from (def_stmt)) + { + enum tree_code def_code = gimple_assign_rhs_code (def_stmt); + if (def_code == PLUS_EXPR + || def_code == MINUS_EXPR) + { + tree def_rhs1 = gimple_assign_rhs1 (def_stmt); + tree def_rhs2 = gimple_assign_rhs2 (def_stmt); + if (operand_equal_p (def_rhs1, rhs2, 0) + && code == MINUS_EXPR) + { + /* (A +- B) - A -> +- B. */ + code = ((def_code == PLUS_EXPR) + ? TREE_CODE (def_rhs2) : NEGATE_EXPR); + rhs1 = def_rhs2; + rhs2 = NULL_TREE; + gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); + gcc_assert (gsi_stmt (*gsi) == stmt); + gimple_set_modified (stmt, true); + } + else if (operand_equal_p (def_rhs2, rhs2, 0) + && code != def_code) + { + /* (A +- B) -+ B -> A. */ + code = TREE_CODE (def_rhs1); + rhs1 = def_rhs1; + rhs2 = NULL_TREE; + gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); + gcc_assert (gsi_stmt (*gsi) == stmt); + gimple_set_modified (stmt, true); + } + else if (TREE_CODE (rhs2) == INTEGER_CST + && TREE_CODE (def_rhs1) == INTEGER_CST) + { + /* (CST +- A) +- CST -> CST +- A. */ + tree cst = fold_binary (code, TREE_TYPE (rhs1), + def_rhs1, rhs2); + if (cst && !TREE_OVERFLOW (cst)) + { + code = def_code; + gimple_assign_set_rhs_code (stmt, code); + rhs1 = cst; + gimple_assign_set_rhs1 (stmt, rhs1); + rhs2 = def_rhs2; + gimple_assign_set_rhs2 (stmt, rhs2); + gimple_set_modified (stmt, true); + } + } + else if (TREE_CODE (rhs2) == INTEGER_CST + && TREE_CODE (def_rhs2) == INTEGER_CST + && def_code == PLUS_EXPR) + { + /* (A + CST) +- CST -> A + CST. */ + tree cst = fold_binary (code, TREE_TYPE (rhs1), + def_rhs2, rhs2); + if (cst && !TREE_OVERFLOW (cst)) + { + code = PLUS_EXPR; + gimple_assign_set_rhs_code (stmt, code); + rhs1 = def_rhs1; + gimple_assign_set_rhs1 (stmt, rhs1); + rhs2 = cst; + gimple_assign_set_rhs2 (stmt, rhs2); + gimple_set_modified (stmt, true); + } + } + } + else if (def_code == BIT_NOT_EXPR + && INTEGRAL_TYPE_P (TREE_TYPE (rhs1))) + { + tree def_rhs1 = gimple_assign_rhs1 (def_stmt); + if (code == PLUS_EXPR + && operand_equal_p (def_rhs1, rhs2, 0)) + { + /* ~A + A -> -1. */ + code = INTEGER_CST; + rhs1 = build_int_cst_type (TREE_TYPE (rhs2), -1); + rhs2 = NULL_TREE; + gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); + gcc_assert (gsi_stmt (*gsi) == stmt); + gimple_set_modified (stmt, true); + } + else if (code == PLUS_EXPR + && integer_onep (rhs1)) + { + /* ~A + 1 -> -A. */ + code = NEGATE_EXPR; + rhs1 = def_rhs1; + rhs2 = NULL_TREE; + gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); + gcc_assert (gsi_stmt (*gsi) == stmt); + gimple_set_modified (stmt, true); + } + } + } + } + + if (rhs2 && TREE_CODE (rhs2) == SSA_NAME) + { + gimple def_stmt = SSA_NAME_DEF_STMT (rhs2); + if (is_gimple_assign (def_stmt) && can_propagate_from (def_stmt)) + { + enum tree_code def_code = gimple_assign_rhs_code (def_stmt); + if (def_code == PLUS_EXPR + || def_code == MINUS_EXPR) + { + tree def_rhs1 = gimple_assign_rhs1 (def_stmt); + tree def_rhs2 = gimple_assign_rhs2 (def_stmt); + if (operand_equal_p (def_rhs1, rhs1, 0) + && code == MINUS_EXPR) + { + /* A - (A +- B) -> -+ B. */ + code = ((def_code == PLUS_EXPR) + ? NEGATE_EXPR : TREE_CODE (def_rhs2)); + rhs1 = def_rhs2; + rhs2 = NULL_TREE; + gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); + gcc_assert (gsi_stmt (*gsi) == stmt); + gimple_set_modified (stmt, true); + } + else if (operand_equal_p (def_rhs2, rhs1, 0) + && code != def_code) + { + /* A +- (B +- A) -> +- B. */ + code = ((code == PLUS_EXPR) + ? TREE_CODE (def_rhs1) : NEGATE_EXPR); + rhs1 = def_rhs1; + rhs2 = NULL_TREE; + gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); + gcc_assert (gsi_stmt (*gsi) == stmt); + gimple_set_modified (stmt, true); + } + else if (TREE_CODE (rhs1) == INTEGER_CST + && TREE_CODE (def_rhs1) == INTEGER_CST) + { + /* CST +- (CST +- A) -> CST +- A. */ + tree cst = fold_binary (code, TREE_TYPE (rhs2), + rhs1, def_rhs1); + if (cst && !TREE_OVERFLOW (cst)) + { + code = (code == def_code ? PLUS_EXPR : MINUS_EXPR); + gimple_assign_set_rhs_code (stmt, code); + rhs1 = cst; + gimple_assign_set_rhs1 (stmt, rhs1); + rhs2 = def_rhs2; + gimple_assign_set_rhs2 (stmt, rhs2); + gimple_set_modified (stmt, true); + } + } + else if (TREE_CODE (rhs1) == INTEGER_CST + && TREE_CODE (def_rhs2) == INTEGER_CST) + { + /* CST +- (A +- CST) -> CST +- A. */ + tree cst = fold_binary (def_code == code + ? PLUS_EXPR : MINUS_EXPR, + TREE_TYPE (rhs2), + rhs1, def_rhs2); + if (cst && !TREE_OVERFLOW (cst)) + { + rhs1 = cst; + gimple_assign_set_rhs1 (stmt, rhs1); + rhs2 = def_rhs1; + gimple_assign_set_rhs2 (stmt, rhs2); + gimple_set_modified (stmt, true); + } + } + } + else if (def_code == BIT_NOT_EXPR + && INTEGRAL_TYPE_P (TREE_TYPE (rhs2))) + { + tree def_rhs1 = gimple_assign_rhs1 (def_stmt); + if (code == PLUS_EXPR + && operand_equal_p (def_rhs1, rhs1, 0)) + { + /* A + ~A -> -1. */ + code = INTEGER_CST; + rhs1 = build_int_cst_type (TREE_TYPE (rhs1), -1); + rhs2 = NULL_TREE; + gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE); + gcc_assert (gsi_stmt (*gsi) == stmt); + gimple_set_modified (stmt, true); + } + } + } + } + +out: + if (gimple_modified_p (stmt)) + { + fold_stmt_inplace (gsi); update_stmt (stmt); + if (maybe_clean_or_replace_eh_stmt (stmt, stmt) + && gimple_purge_dead_eh_edges (gimple_bb (stmt))) + return true; } - return; + + return false; } -/* Main entry point for the forward propagation optimizer. */ +/* Combine two conversions in a row for the second conversion at *GSI. + Returns 1 if there were any changes made, 2 if cfg-cleanup needs to + run. Else it returns 0. */ + +static int +combine_conversions (gimple_stmt_iterator *gsi) +{ + gimple stmt = gsi_stmt (*gsi); + gimple def_stmt; + tree op0, lhs; + enum tree_code code = gimple_assign_rhs_code (stmt); + + gcc_checking_assert (CONVERT_EXPR_CODE_P (code) + || code == FLOAT_EXPR + || code == FIX_TRUNC_EXPR); + + lhs = gimple_assign_lhs (stmt); + op0 = gimple_assign_rhs1 (stmt); + if (useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (op0))) + { + gimple_assign_set_rhs_code (stmt, TREE_CODE (op0)); + return 1; + } + + if (TREE_CODE (op0) != SSA_NAME) + return 0; + + def_stmt = SSA_NAME_DEF_STMT (op0); + if (!is_gimple_assign (def_stmt)) + return 0; + + if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt))) + { + tree defop0 = gimple_assign_rhs1 (def_stmt); + tree type = TREE_TYPE (lhs); + tree inside_type = TREE_TYPE (defop0); + tree inter_type = TREE_TYPE (op0); + int inside_int = INTEGRAL_TYPE_P (inside_type); + int inside_ptr = POINTER_TYPE_P (inside_type); + int inside_float = FLOAT_TYPE_P (inside_type); + int inside_vec = TREE_CODE (inside_type) == VECTOR_TYPE; + unsigned int inside_prec = TYPE_PRECISION (inside_type); + int inside_unsignedp = TYPE_UNSIGNED (inside_type); + int inter_int = INTEGRAL_TYPE_P (inter_type); + int inter_ptr = POINTER_TYPE_P (inter_type); + int inter_float = FLOAT_TYPE_P (inter_type); + int inter_vec = TREE_CODE (inter_type) == VECTOR_TYPE; + unsigned int inter_prec = TYPE_PRECISION (inter_type); + int inter_unsignedp = TYPE_UNSIGNED (inter_type); + int final_int = INTEGRAL_TYPE_P (type); + int final_ptr = POINTER_TYPE_P (type); + int final_float = FLOAT_TYPE_P (type); + int final_vec = TREE_CODE (type) == VECTOR_TYPE; + unsigned int final_prec = TYPE_PRECISION (type); + int final_unsignedp = TYPE_UNSIGNED (type); + + /* Don't propagate ssa names that occur in abnormal phis. */ + if (TREE_CODE (defop0) == SSA_NAME + && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (defop0)) + return 0; + + /* In addition to the cases of two conversions in a row + handled below, if we are converting something to its own + type via an object of identical or wider precision, neither + conversion is needed. */ + if (useless_type_conversion_p (type, inside_type) + && (((inter_int || inter_ptr) && final_int) + || (inter_float && final_float)) + && inter_prec >= final_prec) + { + gimple_assign_set_rhs1 (stmt, unshare_expr (defop0)); + gimple_assign_set_rhs_code (stmt, TREE_CODE (defop0)); + update_stmt (stmt); + return remove_prop_source_from_use (op0) ? 2 : 1; + } + + /* Likewise, if the intermediate and initial types are either both + float or both integer, we don't need the middle conversion if the + former is wider than the latter and doesn't change the signedness + (for integers). Avoid this if the final type is a pointer since + then we sometimes need the middle conversion. Likewise if the + final type has a precision not equal to the size of its mode. */ + if (((inter_int && inside_int) + || (inter_float && inside_float) + || (inter_vec && inside_vec)) + && inter_prec >= inside_prec + && (inter_float || inter_vec + || inter_unsignedp == inside_unsignedp) + && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type)) + && TYPE_MODE (type) == TYPE_MODE (inter_type)) + && ! final_ptr + && (! final_vec || inter_prec == inside_prec)) + { + gimple_assign_set_rhs1 (stmt, defop0); + update_stmt (stmt); + return remove_prop_source_from_use (op0) ? 2 : 1; + } + + /* If we have a sign-extension of a zero-extended value, we can + replace that by a single zero-extension. */ + if (inside_int && inter_int && final_int + && inside_prec < inter_prec && inter_prec < final_prec + && inside_unsignedp && !inter_unsignedp) + { + gimple_assign_set_rhs1 (stmt, defop0); + update_stmt (stmt); + return remove_prop_source_from_use (op0) ? 2 : 1; + } + + /* Two conversions in a row are not needed unless: + - some conversion is floating-point (overstrict for now), or + - some conversion is a vector (overstrict for now), or + - the intermediate type is narrower than both initial and + final, or + - the intermediate type and innermost type differ in signedness, + and the outermost type is wider than the intermediate, or + - the initial type is a pointer type and the precisions of the + intermediate and final types differ, or + - the final type is a pointer type and the precisions of the + initial and intermediate types differ. */ + if (! inside_float && ! inter_float && ! final_float + && ! inside_vec && ! inter_vec && ! final_vec + && (inter_prec >= inside_prec || inter_prec >= final_prec) + && ! (inside_int && inter_int + && inter_unsignedp != inside_unsignedp + && inter_prec < final_prec) + && ((inter_unsignedp && inter_prec > inside_prec) + == (final_unsignedp && final_prec > inter_prec)) + && ! (inside_ptr && inter_prec != final_prec) + && ! (final_ptr && inside_prec != inter_prec) + && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type)) + && TYPE_MODE (type) == TYPE_MODE (inter_type))) + { + gimple_assign_set_rhs1 (stmt, defop0); + update_stmt (stmt); + return remove_prop_source_from_use (op0) ? 2 : 1; + } + + /* A truncation to an unsigned type should be canonicalized as + bitwise and of a mask. */ + if (final_int && inter_int && inside_int + && final_prec == inside_prec + && final_prec > inter_prec + && inter_unsignedp) + { + tree tem; + tem = fold_build2 (BIT_AND_EXPR, inside_type, + defop0, + double_int_to_tree + (inside_type, double_int_mask (inter_prec))); + if (!useless_type_conversion_p (type, inside_type)) + { + tem = force_gimple_operand_gsi (gsi, tem, true, NULL_TREE, true, + GSI_SAME_STMT); + gimple_assign_set_rhs1 (stmt, tem); + } + else + gimple_assign_set_rhs_from_tree (gsi, tem); + update_stmt (gsi_stmt (*gsi)); + return 1; + } + } + + return 0; +} + +/* Main entry point for the forward propagation and statement combine + optimizer. */ static unsigned int -tree_ssa_forward_propagate_single_use_vars (void) +ssa_forward_propagate_and_combine (void) { basic_block bb; unsigned int todoflags = 0; @@ -1369,141 +2370,201 @@ tree_ssa_forward_propagate_single_use_vars (void) FOR_EACH_BB (bb) { - gimple_stmt_iterator gsi; + gimple_stmt_iterator gsi, prev; + bool prev_initialized; - /* Note we update GSI within the loop as necessary. */ + /* Apply forward propagation to all stmts in the basic-block. + Note we update GSI within the loop as necessary. */ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); ) { gimple stmt = gsi_stmt (gsi); + tree lhs, rhs; + enum tree_code code; - /* If this statement sets an SSA_NAME to an address, - try to propagate the address into the uses of the SSA_NAME. */ - if (is_gimple_assign (stmt)) + if (!is_gimple_assign (stmt)) { - tree lhs = gimple_assign_lhs (stmt); - tree rhs = gimple_assign_rhs1 (stmt); + gsi_next (&gsi); + continue; + } - if (TREE_CODE (lhs) != SSA_NAME) - { - gsi_next (&gsi); - continue; - } + lhs = gimple_assign_lhs (stmt); + rhs = gimple_assign_rhs1 (stmt); + code = gimple_assign_rhs_code (stmt); + if (TREE_CODE (lhs) != SSA_NAME + || has_zero_uses (lhs)) + { + gsi_next (&gsi); + continue; + } - if (gimple_assign_rhs_code (stmt) == ADDR_EXPR - /* Handle pointer conversions on invariant addresses - as well, as this is valid gimple. */ - || (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt)) - && TREE_CODE (rhs) == ADDR_EXPR - && POINTER_TYPE_P (TREE_TYPE (lhs)))) + /* If this statement sets an SSA_NAME to an address, + try to propagate the address into the uses of the SSA_NAME. */ + if (code == ADDR_EXPR + /* Handle pointer conversions on invariant addresses + as well, as this is valid gimple. */ + || (CONVERT_EXPR_CODE_P (code) + && TREE_CODE (rhs) == ADDR_EXPR + && POINTER_TYPE_P (TREE_TYPE (lhs)))) + { + tree base = get_base_address (TREE_OPERAND (rhs, 0)); + if ((!base + || !DECL_P (base) + || decl_address_invariant_p (base)) + && !stmt_references_abnormal_ssa_name (stmt) + && forward_propagate_addr_expr (lhs, rhs)) { - tree base = get_base_address (TREE_OPERAND (rhs, 0)); - if ((!base - || !DECL_P (base) - || decl_address_invariant_p (base)) - && !stmt_references_abnormal_ssa_name (stmt) - && forward_propagate_addr_expr (lhs, rhs)) - { - release_defs (stmt); - todoflags |= TODO_remove_unused_locals; - gsi_remove (&gsi, true); - } - else - gsi_next (&gsi); + release_defs (stmt); + todoflags |= TODO_remove_unused_locals; + gsi_remove (&gsi, true); } - else if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR) - { - if (TREE_CODE (gimple_assign_rhs2 (stmt)) == INTEGER_CST - /* ??? Better adjust the interface to that function - instead of building new trees here. */ - && forward_propagate_addr_expr - (lhs, - build1 (ADDR_EXPR, - TREE_TYPE (rhs), + else + gsi_next (&gsi); + } + else if (code == POINTER_PLUS_EXPR) + { + tree off = gimple_assign_rhs2 (stmt); + if (TREE_CODE (off) == INTEGER_CST + && can_propagate_from (stmt) + && !simple_iv_increment_p (stmt) + /* ??? Better adjust the interface to that function + instead of building new trees here. */ + && forward_propagate_addr_expr + (lhs, + build1_loc (gimple_location (stmt), + ADDR_EXPR, TREE_TYPE (rhs), fold_build2 (MEM_REF, TREE_TYPE (TREE_TYPE (rhs)), rhs, - fold_convert - (ptr_type_node, - gimple_assign_rhs2 (stmt)))))) - { - release_defs (stmt); - todoflags |= TODO_remove_unused_locals; - gsi_remove (&gsi, true); - } - else if (is_gimple_min_invariant (rhs)) - { - /* Make sure to fold &a[0] + off_1 here. */ - fold_stmt_inplace (stmt); - update_stmt (stmt); - if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR) - gsi_next (&gsi); - } - else - gsi_next (&gsi); - } - else if ((gimple_assign_rhs_code (stmt) == BIT_NOT_EXPR - || gimple_assign_rhs_code (stmt) == NEGATE_EXPR) - && TREE_CODE (rhs) == SSA_NAME) + fold_convert (ptr_type_node, + off))))) { - simplify_not_neg_expr (&gsi); - gsi_next (&gsi); + release_defs (stmt); + todoflags |= TODO_remove_unused_locals; + gsi_remove (&gsi, true); } - else if (gimple_assign_rhs_code (stmt) == COND_EXPR) - { - /* In this case the entire COND_EXPR is in rhs1. */ - int did_something; - fold_defer_overflow_warnings (); - did_something = forward_propagate_into_cond (&gsi); - stmt = gsi_stmt (gsi); - if (did_something == 2) - cfg_changed = true; - fold_undefer_overflow_warnings (!TREE_NO_WARNING (rhs) - && did_something, stmt, WARN_STRICT_OVERFLOW_CONDITIONAL); - gsi_next (&gsi); - } - else if (TREE_CODE_CLASS (gimple_assign_rhs_code (stmt)) - == tcc_comparison) + else if (is_gimple_min_invariant (rhs)) { - if (forward_propagate_comparison (stmt)) - { - release_defs (stmt); - todoflags |= TODO_remove_unused_locals; - gsi_remove (&gsi, true); - } - else + /* Make sure to fold &a[0] + off_1 here. */ + fold_stmt_inplace (&gsi); + update_stmt (stmt); + if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR) gsi_next (&gsi); } - else if (gimple_assign_rhs_code (stmt) == BIT_AND_EXPR) - { - simplify_bitwise_and (&gsi, stmt); - gsi_next (&gsi); - } else gsi_next (&gsi); } - else if (gimple_code (stmt) == GIMPLE_SWITCH) + else if (TREE_CODE_CLASS (code) == tcc_comparison) { - simplify_gimple_switch (stmt); + if (forward_propagate_comparison (stmt)) + cfg_changed = true; gsi_next (&gsi); } - else if (gimple_code (stmt) == GIMPLE_COND) + else + gsi_next (&gsi); + } + + /* Combine stmts with the stmts defining their operands. + Note we update GSI within the loop as necessary. */ + prev_initialized = false; + for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi);) + { + gimple stmt = gsi_stmt (gsi); + bool changed = false; + + switch (gimple_code (stmt)) + { + case GIMPLE_ASSIGN: + { + tree rhs1 = gimple_assign_rhs1 (stmt); + enum tree_code code = gimple_assign_rhs_code (stmt); + + if ((code == BIT_NOT_EXPR + || code == NEGATE_EXPR) + && TREE_CODE (rhs1) == SSA_NAME) + changed = simplify_not_neg_expr (&gsi); + else if (code == COND_EXPR) + { + /* In this case the entire COND_EXPR is in rhs1. */ + changed |= forward_propagate_into_cond (&gsi); + stmt = gsi_stmt (gsi); + } + else if (TREE_CODE_CLASS (code) == tcc_comparison) + { + int did_something; + did_something = forward_propagate_into_comparison (&gsi); + if (did_something == 2) + cfg_changed = true; + changed = did_something != 0; + } + else if (code == BIT_AND_EXPR + || code == BIT_IOR_EXPR + || code == BIT_XOR_EXPR) + changed = simplify_bitwise_binary (&gsi); + else if (code == PLUS_EXPR + || code == MINUS_EXPR) + changed = associate_plusminus (&gsi); + else if (CONVERT_EXPR_CODE_P (code) + || code == FLOAT_EXPR + || code == FIX_TRUNC_EXPR) + { + int did_something = combine_conversions (&gsi); + if (did_something == 2) + cfg_changed = true; + changed = did_something != 0; + } + break; + } + + case GIMPLE_SWITCH: + changed = simplify_gimple_switch (stmt); + break; + + case GIMPLE_COND: + { + int did_something; + did_something = forward_propagate_into_gimple_cond (stmt); + if (did_something == 2) + cfg_changed = true; + changed = did_something != 0; + break; + } + + case GIMPLE_CALL: + { + tree callee = gimple_call_fndecl (stmt); + if (callee != NULL_TREE + && DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL) + changed = simplify_builtin_call (&gsi, callee); + break; + } + + default:; + } + + if (changed) { - int did_something; - fold_defer_overflow_warnings (); - did_something = forward_propagate_into_gimple_cond (stmt); - if (did_something == 2) - cfg_changed = true; - fold_undefer_overflow_warnings (did_something, stmt, - WARN_STRICT_OVERFLOW_CONDITIONAL); - gsi_next (&gsi); + /* If the stmt changed then re-visit it and the statements + inserted before it. */ + if (!prev_initialized) + gsi = gsi_start_bb (bb); + else + { + gsi = prev; + gsi_next (&gsi); + } } else - gsi_next (&gsi); + { + prev = gsi; + prev_initialized = true; + gsi_next (&gsi); + } } } if (cfg_changed) todoflags |= TODO_cleanup_cfg; + return todoflags; } @@ -1520,7 +2581,7 @@ struct gimple_opt_pass pass_forwprop = GIMPLE_PASS, "forwprop", /* name */ gate_forwprop, /* gate */ - tree_ssa_forward_propagate_single_use_vars, /* execute */ + ssa_forward_propagate_and_combine, /* execute */ NULL, /* sub */ NULL, /* next */ 0, /* static_pass_number */ @@ -1529,10 +2590,8 @@ struct gimple_opt_pass pass_forwprop = 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ - TODO_dump_func - | TODO_ggc_collect + TODO_ggc_collect | TODO_update_ssa | TODO_verify_ssa /* todo_flags_finish */ } }; -