X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Ftree-ssa-forwprop.c;h=fe2e89fa918525cae52f8a61cb1c6f605d8f8016;hb=3b01567f28b62f8d753edb3a490064eeeabb5420;hp=1766869d0c46e19e512d1b4207478347caf0f057;hpb=b9e98b8aaf6868b21168913ea3d82df38d4d1430;p=pf3gnuchains%2Fgcc-fork.git diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c index 1766869d0c4..fe2e89fa918 100644 --- a/gcc/tree-ssa-forwprop.c +++ b/gcc/tree-ssa-forwprop.c @@ -1,5 +1,6 @@ /* Forward propagation of expressions for single use variables. - Copyright (C) 2004, 2005, 2007, 2008 Free Software Foundation, Inc. + Copyright (C) 2004, 2005, 2007, 2008, 2009, 2010, 2011 + Free Software Foundation, Inc. This file is part of GCC. @@ -21,31 +22,26 @@ along with GCC; see the file COPYING3. If not see #include "system.h" #include "coretypes.h" #include "tm.h" -#include "ggc.h" #include "tree.h" -#include "rtl.h" #include "tm_p.h" #include "basic-block.h" #include "timevar.h" -#include "diagnostic.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 form of tree combination. It is hoped all of this can disappear when we have a generalized tree combiner. - Note carefully that after propagation the resulting statement - must still be a proper gimple statement. Right now we simply - only perform propagations we know will result in valid gimple - code. One day we'll want to generalize this code. - One class of common cases we handle is forward propagating a single use - variable into a COND_EXPR. + variable into a COND_EXPR. bb0: x = a COND b; @@ -55,13 +51,13 @@ along with GCC; see the file COPYING3. If not see bb0: if (a COND b) goto ... else goto ... - + Similarly for the tests (x == 0), (x != 0), (x == 1) and (x != 1). Or (assuming c1 and c2 are constants): bb0: - x = a + c1; + x = a + c1; if (x EQ/NEQ c2) goto ... else goto ... Will be transformed into: @@ -70,7 +66,7 @@ along with GCC; see the file COPYING3. If not see if (a EQ/NEQ (c2 - c1)) goto ... else goto ... Similarly for x = a - c1. - + Or bb0: @@ -124,6 +120,14 @@ along with GCC; see the file COPYING3. If not see res = x->y->z; Or + ptr = (type1*)&type2var; + res = *ptr + + Will get turned into (if type1 and type2 are the same size + and neither have volatile on them): + res = VIEW_CONVERT_EXPR(type2var) + + Or ptr = &x[0]; ptr2 = ptr + ; @@ -143,6 +147,14 @@ along with GCC; see the file COPYING3. If not see ptr2 = &x[index]; + Or + ssa = (int) decl + res = ssa & 1 + + Provided that decl has known alignment >= 2, will get turned into + + res = 0 + We also propagate casts into SWITCH_EXPR and COND_EXPR conditions to allow us to remove the cast and {NOT_EXPR,NEG_EXPR} into a subsequent {NOT_EXPR,NEG_EXPR}. @@ -154,6 +166,7 @@ static bool forward_propagate_addr_expr (tree name, tree rhs); /* Set to true if we delete EH edges during the optimization. */ static bool cfg_changed; +static tree rhs_to_tree (tree type, gimple stmt); /* Get the next statement we can propagate NAME's value into skipping trivial copies. Returns the statement that is suitable as a @@ -161,25 +174,24 @@ static bool cfg_changed; This only returns destinations in a single-use chain. FINAL_NAME_P if non-NULL is written to the ssa name that represents the use. */ -static tree +static gimple get_prop_dest_stmt (tree name, tree *final_name_p) { use_operand_p use; - tree use_stmt; + gimple use_stmt; do { /* If name has multiple uses, bail out. */ if (!single_imm_use (name, &use, &use_stmt)) - return NULL_TREE; + return NULL; /* If this is not a trivial copy, we found it. */ - if (TREE_CODE (use_stmt) != GIMPLE_MODIFY_STMT - || TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 0)) != SSA_NAME - || GIMPLE_STMT_OPERAND (use_stmt, 1) != name) + if (!gimple_assign_ssa_name_copy_p (use_stmt) + || gimple_assign_rhs1 (use_stmt) != name) break; /* Continue searching uses of the copy destination. */ - name = GIMPLE_STMT_OPERAND (use_stmt, 0); + name = gimple_assign_lhs (use_stmt); } while (1); if (final_name_p) @@ -196,27 +208,27 @@ get_prop_dest_stmt (tree name, tree *final_name_p) it is set to whether the chain to NAME is a single use chain or not. SINGLE_USE_P is not written to if SINGLE_USE_ONLY is set. */ -static tree +static gimple get_prop_source_stmt (tree name, bool single_use_only, bool *single_use_p) { bool single_use = true; do { - tree def_stmt = SSA_NAME_DEF_STMT (name); + gimple def_stmt = SSA_NAME_DEF_STMT (name); if (!has_single_use (name)) { single_use = false; if (single_use_only) - return NULL_TREE; + return NULL; } /* If name is defined by a PHI node or is the default def, bail out. */ - if (TREE_CODE (def_stmt) != GIMPLE_MODIFY_STMT) - return NULL_TREE; + if (!is_gimple_assign (def_stmt)) + return NULL; - /* If name is not a simple copy destination, we found it. */ - if (TREE_CODE (GIMPLE_STMT_OPERAND (def_stmt, 1)) != SSA_NAME) + /* If def_stmt is not a simple copy, we possibly found it. */ + if (!gimple_assign_ssa_name_copy_p (def_stmt)) { tree rhs; @@ -225,20 +237,19 @@ get_prop_source_stmt (tree name, bool single_use_only, bool *single_use_p) /* We can look through pointer conversions in the search for a useful stmt for the comparison folding. */ - rhs = GIMPLE_STMT_OPERAND (def_stmt, 1); - if ((TREE_CODE (rhs) == NOP_EXPR - || TREE_CODE (rhs) == CONVERT_EXPR) - && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME - && POINTER_TYPE_P (TREE_TYPE (rhs)) - && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (rhs, 0)))) - name = TREE_OPERAND (rhs, 0); + rhs = gimple_assign_rhs1 (def_stmt); + if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt)) + && TREE_CODE (rhs) == SSA_NAME + && POINTER_TYPE_P (TREE_TYPE (gimple_assign_lhs (def_stmt))) + && POINTER_TYPE_P (TREE_TYPE (rhs))) + name = rhs; else return def_stmt; } else { /* Continue searching the def of the copy source name. */ - name = GIMPLE_STMT_OPERAND (def_stmt, 1); + name = gimple_assign_rhs1 (def_stmt); } } while (1); } @@ -247,88 +258,108 @@ get_prop_source_stmt (tree name, bool single_use_only, bool *single_use_p) propagation source. Returns true if so, otherwise false. */ static bool -can_propagate_from (tree def_stmt) +can_propagate_from (gimple def_stmt) { - tree rhs = GIMPLE_STMT_OPERAND (def_stmt, 1); + gcc_assert (is_gimple_assign (def_stmt)); /* If the rhs has side-effects we cannot propagate from it. */ - if (TREE_SIDE_EFFECTS (rhs)) + if (gimple_has_volatile_ops (def_stmt)) return false; /* If the rhs is a load we cannot propagate from it. */ - if (REFERENCE_CLASS_P (rhs)) + if (TREE_CODE_CLASS (gimple_assign_rhs_code (def_stmt)) == tcc_reference + || TREE_CODE_CLASS (gimple_assign_rhs_code (def_stmt)) == tcc_declaration) return false; /* Constants can be always propagated. */ - if (is_gimple_min_invariant (rhs)) + if (gimple_assign_single_p (def_stmt) + && is_gimple_min_invariant (gimple_assign_rhs1 (def_stmt))) return true; /* We cannot propagate ssa names that occur in abnormal phi nodes. */ - switch (TREE_CODE_LENGTH (TREE_CODE (rhs))) - { - case 3: - if (TREE_OPERAND (rhs, 2) != NULL_TREE - && TREE_CODE (TREE_OPERAND (rhs, 2)) == SSA_NAME - && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (TREE_OPERAND (rhs, 2))) - return false; - case 2: - if (TREE_OPERAND (rhs, 1) != NULL_TREE - && TREE_CODE (TREE_OPERAND (rhs, 1)) == SSA_NAME - && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (TREE_OPERAND (rhs, 1))) - return false; - case 1: - if (TREE_OPERAND (rhs, 0) != NULL_TREE - && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME - && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (TREE_OPERAND (rhs, 0))) - return false; - break; - - default: - 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 function - pointers to be canonicalized and in this case this optimization could - eliminate a necessary canonicalization. */ - if ((TREE_CODE (rhs) == NOP_EXPR - || TREE_CODE (rhs) == CONVERT_EXPR) - && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (rhs, 0))) - && TREE_CODE (TREE_TYPE (TREE_TYPE - (TREE_OPERAND (rhs, 0)))) == FUNCTION_TYPE) - return false; + then we can not apply optimizations as some targets require + function pointers to be canonicalized and in this case this + optimization could eliminate a necessary canonicalization. */ + if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt))) + { + tree rhs = gimple_assign_rhs1 (def_stmt); + if (POINTER_TYPE_P (TREE_TYPE (rhs)) + && TREE_CODE (TREE_TYPE (TREE_TYPE (rhs))) == FUNCTION_TYPE) + return false; + } 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, tree up_to_stmt) +remove_prop_source_from_use (tree name) { - block_stmt_iterator bsi; - tree stmt; + gimple_stmt_iterator gsi; + gimple stmt; + bool cfg_changed = false; do { - if (!has_zero_uses (name)) - return false; + basic_block bb; - stmt = SSA_NAME_DEF_STMT (name); - if (stmt == up_to_stmt) - return true; + if (SSA_NAME_IN_FREE_LIST (name) + || SSA_NAME_IS_DEFAULT_DEF (name) + || !has_zero_uses (name)) + return cfg_changed; - bsi = bsi_for_stmt (stmt); + stmt = SSA_NAME_DEF_STMT (name); + if (gimple_code (stmt) == GIMPLE_PHI + || gimple_has_side_effects (stmt)) + return cfg_changed; + + bb = gimple_bb (stmt); + gsi = gsi_for_stmt (stmt); + unlink_stmt_vdef (stmt); + gsi_remove (&gsi, true); release_defs (stmt); - bsi_remove (&bsi, true); + cfg_changed |= gimple_purge_dead_eh_edges (bb); - name = GIMPLE_STMT_OPERAND (stmt, 1); - } while (TREE_CODE (name) == SSA_NAME); + 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, + converted to type TYPE. + + This should disappear, but is needed so we can combine expressions and use + the fold() interfaces. Long term, we need to develop folding and combine + routines that deal with gimple exclusively . */ + +static tree +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_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) + return build1 (code, type, gimple_assign_rhs1 (stmt)); + else if (get_gimple_rhs_class (code) == GIMPLE_SINGLE_RHS) + return gimple_assign_rhs1 (stmt); + else + gcc_unreachable (); } /* Combine OP0 CODE OP1 in the context of a COND_EXPR. Returns @@ -338,16 +369,20 @@ remove_prop_source_from_use (tree name, tree up_to_stmt) considered simplified. */ static tree -combine_cond_expr_cond (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 (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)); @@ -356,137 +391,263 @@ combine_cond_expr_cond (enum tree_code code, tree type, t = canonicalize_cond_expr_cond (t); /* Bail out if we required an invariant but didn't get one. */ - if (!t - || (invariant_only - && !is_gimple_min_invariant (t))) - return NULL_TREE; + if (!t || (invariant_only && !is_gimple_min_invariant (t))) + { + 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 statement STMT into the conditional if that simplifies it. + in GIMPLE_COND 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. */ + changes and two if cfg_cleanup needs to run. + + This must be kept in sync with forward_propagate_into_cond. */ static int -forward_propagate_into_cond (tree cond_expr, tree stmt) +forward_propagate_into_gimple_cond (gimple stmt) { - int did_something = 0; + 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"); + } - do { - tree tmp = NULL_TREE; - tree cond = COND_EXPR_COND (cond_expr); - tree name, def_stmt, rhs0 = NULL_TREE, rhs1 = NULL_TREE; - 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 != NULL_TREE - && can_propagate_from (def_stmt)) - { - tree op1 = TREE_OPERAND (cond, 1); - rhs0 = GIMPLE_STMT_OPERAND (def_stmt, 1); - tmp = combine_cond_expr_cond (TREE_CODE (cond), boolean_type_node, - fold_convert (TREE_TYPE (op1), 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 == NULL_TREE - || !can_propagate_from (def_stmt)) - return did_something; - - rhs1 = GIMPLE_STMT_OPERAND (def_stmt, 1); - tmp = combine_cond_expr_cond (TREE_CODE (cond), boolean_type_node, - op0, - fold_convert (TREE_TYPE (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 (TREE_CODE (cond), boolean_type_node, - rhs0, - fold_convert (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 == NULL_TREE - || !can_propagate_from (def_stmt)) - return did_something; - - rhs0 = GIMPLE_STMT_OPERAND (def_stmt, 1); - tmp = combine_cond_expr_cond (NE_EXPR, boolean_type_node, rhs0, - build_int_cst (TREE_TYPE (rhs0), 0), - false); - } + gimple_cond_set_condition_from_tree (stmt, unshare_expr (tmp)); + update_stmt (stmt); - 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"); - } + 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; + } - COND_EXPR_COND (cond_expr) = unshare_expr (tmp); - update_stmt (stmt); + /* 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; + } - /* Remove defining statements. */ - remove_prop_source_from_use (name, NULL); + return 0; +} - if (is_gimple_min_invariant (tmp)) - did_something = 2; - else if (did_something == 0) - did_something = 1; - /* Continue combining. */ - continue; - } +/* Propagate from the ssa name definition statements of COND_EXPR + in the rhs of statement STMT into the conditional if that simplifies it. + Returns true zero if the stmt was changed. */ - break; - } while (1); +static bool +forward_propagate_into_cond (gimple_stmt_iterator *gsi_p) +{ + gimple stmt = gsi_stmt (*gsi_p); + 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 (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"); + } + + 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); - return did_something; + return true; + } + + return 0; } -/* We've just substituted an ADDR_EXPR into stmt. Update all the +/* We've just substituted an ADDR_EXPR into stmt. Update all the relevant data structures to match. */ static void -tidy_after_forward_propagate_addr (tree stmt) +tidy_after_forward_propagate_addr (gimple stmt) { /* We may have turned a trapping insn into a non-trapping insn. */ if (maybe_clean_or_replace_eh_stmt (stmt, stmt) - && tree_purge_dead_eh_edges (bb_for_stmt (stmt))) + && gimple_purge_dead_eh_edges (gimple_bb (stmt))) cfg_changed = true; - if (TREE_CODE (GIMPLE_STMT_OPERAND (stmt, 1)) == ADDR_EXPR) - recompute_tree_invariant_for_addr_expr (GIMPLE_STMT_OPERAND (stmt, 1)); - - mark_symbols_for_renaming (stmt); + if (TREE_CODE (gimple_assign_rhs1 (stmt)) == ADDR_EXPR) + recompute_tree_invariant_for_addr_expr (gimple_assign_rhs1 (stmt)); } -/* DEF_RHS contains the address of the 0th element in an array. +/* DEF_RHS contains the address of the 0th element in an array. USE_STMT uses type of DEF_RHS to compute the address of an arbitrary element within the array. The (variable) byte offset of the element is contained in OFFSET. @@ -503,49 +664,108 @@ tidy_after_forward_propagate_addr (tree stmt) static bool forward_propagate_addr_into_variable_array_index (tree offset, - tree def_rhs, tree use_stmt) + tree def_rhs, + gimple_stmt_iterator *use_stmt_gsi) { - tree index; - - /* Try to find an expression for a proper index. This is either - a multiplication expression by the element size or just the - ssa name we came along in case the element size is one. */ - if (integer_onep (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (def_rhs))))) - index = offset; + tree index, tunit; + gimple offset_def, use_stmt = gsi_stmt (*use_stmt_gsi); + tree new_rhs, tmp; + + if (TREE_CODE (TREE_OPERAND (def_rhs, 0)) == ARRAY_REF) + tunit = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (def_rhs))); + else if (TREE_CODE (TREE_TYPE (TREE_OPERAND (def_rhs, 0))) == ARRAY_TYPE) + tunit = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (TREE_TYPE (def_rhs)))); else + return false; + if (!host_integerp (tunit, 1)) + return false; + + /* Get the offset's defining statement. */ + offset_def = SSA_NAME_DEF_STMT (offset); + + /* Try to find an expression for a proper index. This is either a + multiplication expression by the element size or just the ssa name we came + along in case the element size is one. In that case, however, we do not + allow multiplications because they can be computing index to a higher + level dimension (PR 37861). */ + if (integer_onep (tunit)) { - /* Get the offset's defining statement. */ - offset = SSA_NAME_DEF_STMT (offset); + if (is_gimple_assign (offset_def) + && gimple_assign_rhs_code (offset_def) == MULT_EXPR) + return false; + index = offset; + } + else + { /* The statement which defines OFFSET before type conversion - must be a simple GIMPLE_MODIFY_STMT. */ - if (TREE_CODE (offset) != GIMPLE_MODIFY_STMT) + must be a simple GIMPLE_ASSIGN. */ + if (!is_gimple_assign (offset_def)) return false; /* The RHS of the statement which defines OFFSET must be a - multiplication of an object by the size of the array elements. + multiplication of an object by the size of the array elements. This implicitly verifies that the size of the array elements is constant. */ - offset = GIMPLE_STMT_OPERAND (offset, 1); - if (TREE_CODE (offset) != MULT_EXPR - || TREE_CODE (TREE_OPERAND (offset, 1)) != INTEGER_CST - || !simple_cst_equal (TREE_OPERAND (offset, 1), - TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (def_rhs))))) + if (gimple_assign_rhs_code (offset_def) == MULT_EXPR + && TREE_CODE (gimple_assign_rhs2 (offset_def)) == INTEGER_CST + && tree_int_cst_equal (gimple_assign_rhs2 (offset_def), tunit)) + { + /* The first operand to the MULT_EXPR is the desired index. */ + index = gimple_assign_rhs1 (offset_def); + } + /* If we have idx * tunit + CST * tunit re-associate that. */ + else if ((gimple_assign_rhs_code (offset_def) == PLUS_EXPR + || gimple_assign_rhs_code (offset_def) == MINUS_EXPR) + && TREE_CODE (gimple_assign_rhs1 (offset_def)) == SSA_NAME + && TREE_CODE (gimple_assign_rhs2 (offset_def)) == INTEGER_CST + && (tmp = div_if_zero_remainder (EXACT_DIV_EXPR, + gimple_assign_rhs2 (offset_def), + tunit)) != NULL_TREE) + { + gimple offset_def2 = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (offset_def)); + if (is_gimple_assign (offset_def2) + && gimple_assign_rhs_code (offset_def2) == MULT_EXPR + && TREE_CODE (gimple_assign_rhs2 (offset_def2)) == INTEGER_CST + && tree_int_cst_equal (gimple_assign_rhs2 (offset_def2), tunit)) + { + index = fold_build2 (gimple_assign_rhs_code (offset_def), + TREE_TYPE (offset), + gimple_assign_rhs1 (offset_def2), tmp); + } + else + return false; + } + else return false; - - /* The first operand to the MULT_EXPR is the desired index. */ - index = TREE_OPERAND (offset, 0); } /* Replace the pointer addition with array indexing. */ - GIMPLE_STMT_OPERAND (use_stmt, 1) = unshare_expr (def_rhs); - TREE_OPERAND (TREE_OPERAND (GIMPLE_STMT_OPERAND (use_stmt, 1), 0), 1) - = index; - - /* 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); + index = force_gimple_operand_gsi (use_stmt_gsi, index, true, NULL_TREE, + true, GSI_SAME_STMT); + if (TREE_CODE (TREE_OPERAND (def_rhs, 0)) == ARRAY_REF) + { + new_rhs = unshare_expr (def_rhs); + TREE_OPERAND (TREE_OPERAND (new_rhs, 0), 1) = index; + } + else + { + new_rhs = build4 (ARRAY_REF, TREE_TYPE (TREE_TYPE (TREE_TYPE (def_rhs))), + unshare_expr (TREE_OPERAND (def_rhs, 0)), + index, integer_zero_node, NULL_TREE); + new_rhs = build_fold_addr_expr (new_rhs); + if (!useless_type_conversion_p (TREE_TYPE (gimple_assign_lhs (use_stmt)), + TREE_TYPE (new_rhs))) + { + new_rhs = force_gimple_operand_gsi (use_stmt_gsi, new_rhs, true, + NULL_TREE, true, GSI_SAME_STMT); + new_rhs = fold_convert (TREE_TYPE (gimple_assign_lhs (use_stmt)), + new_rhs); + } + } + gimple_assign_set_rhs_from_tree (use_stmt_gsi, new_rhs); + fold_stmt (use_stmt_gsi); + tidy_after_forward_propagate_addr (gsi_stmt (*use_stmt_gsi)); return true; } @@ -555,21 +775,25 @@ forward_propagate_addr_into_variable_array_index (tree offset, Try to forward propagate the ADDR_EXPR into the use USE_STMT. Often this will allow for removal of an ADDR_EXPR and INDIRECT_REF node or for recovery of array indexing from pointer arithmetic. - + Return true if the propagation was successful (the propagation can be not totally successful, yet things may have been changed). */ static bool -forward_propagate_addr_expr_1 (tree name, tree def_rhs, tree use_stmt, +forward_propagate_addr_expr_1 (tree name, tree def_rhs, + gimple_stmt_iterator *use_stmt_gsi, bool single_use_p) { - tree lhs, rhs, array_ref; - tree *rhsp, *lhsp; + tree lhs, rhs, rhs2, array_ref; + gimple use_stmt = gsi_stmt (*use_stmt_gsi); + enum tree_code rhs_code; + bool res = true; gcc_assert (TREE_CODE (def_rhs) == ADDR_EXPR); - lhs = GIMPLE_STMT_OPERAND (use_stmt, 0); - rhs = GIMPLE_STMT_OPERAND (use_stmt, 1); + lhs = gimple_assign_lhs (use_stmt); + rhs_code = gimple_assign_rhs_code (use_stmt); + rhs = gimple_assign_rhs1 (use_stmt); /* Trivial cases. The use statement could be a trivial copy or a useless conversion. Recurse to the uses of the lhs as copyprop does @@ -577,84 +801,235 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, tree use_stmt, all useless conversions. Treat the case of a single-use name and a conversion to def_rhs type separate, though. */ if (TREE_CODE (lhs) == SSA_NAME - && (rhs == name - || TREE_CODE (rhs) == NOP_EXPR - || TREE_CODE (rhs) == CONVERT_EXPR) - && useless_type_conversion_p (TREE_TYPE (rhs), TREE_TYPE (def_rhs))) + && ((rhs_code == SSA_NAME && rhs == name) + || CONVERT_EXPR_CODE_P (rhs_code))) { - /* Only recurse if we don't deal with a single use. */ - if (!single_use_p) + /* Only recurse if we don't deal with a single use or we cannot + do the propagation to the current statement. In particular + we can end up with a conversion needed for a non-invariant + address which we cannot do in a single statement. */ + if (!single_use_p + || (!useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (def_rhs)) + && (!is_gimple_min_invariant (def_rhs) + || (INTEGRAL_TYPE_P (TREE_TYPE (lhs)) + && POINTER_TYPE_P (TREE_TYPE (def_rhs)) + && (TYPE_PRECISION (TREE_TYPE (lhs)) + > TYPE_PRECISION (TREE_TYPE (def_rhs))))))) return forward_propagate_addr_expr (lhs, def_rhs); - GIMPLE_STMT_OPERAND (use_stmt, 1) = unshare_expr (def_rhs); + gimple_assign_set_rhs1 (use_stmt, unshare_expr (def_rhs)); + if (useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (def_rhs))) + gimple_assign_set_rhs_code (use_stmt, TREE_CODE (def_rhs)); + else + gimple_assign_set_rhs_code (use_stmt, NOP_EXPR); + return true; + } + + /* Propagate through constant pointer adjustments. */ + if (TREE_CODE (lhs) == SSA_NAME + && rhs_code == POINTER_PLUS_EXPR + && rhs == name + && TREE_CODE (gimple_assign_rhs2 (use_stmt)) == INTEGER_CST) + { + tree new_def_rhs; + /* As we come here with non-invariant addresses in def_rhs we need + to make sure we can build a valid constant offsetted address + for further propagation. Simply rely on fold building that + and check after the fact. */ + new_def_rhs = fold_build2 (MEM_REF, TREE_TYPE (TREE_TYPE (rhs)), + def_rhs, + fold_convert (ptr_type_node, + gimple_assign_rhs2 (use_stmt))); + if (TREE_CODE (new_def_rhs) == MEM_REF + && !is_gimple_mem_ref_addr (TREE_OPERAND (new_def_rhs, 0))) + return false; + new_def_rhs = build_fold_addr_expr_with_type (new_def_rhs, + TREE_TYPE (rhs)); + + /* Recurse. If we could propagate into all uses of lhs do not + bother to replace into the current use but just pretend we did. */ + if (TREE_CODE (new_def_rhs) == ADDR_EXPR + && forward_propagate_addr_expr (lhs, new_def_rhs)) + return true; + + if (useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (new_def_rhs))) + gimple_assign_set_rhs_with_ops (use_stmt_gsi, TREE_CODE (new_def_rhs), + new_def_rhs, NULL_TREE); + else if (is_gimple_min_invariant (new_def_rhs)) + gimple_assign_set_rhs_with_ops (use_stmt_gsi, NOP_EXPR, + new_def_rhs, NULL_TREE); + else + return false; + gcc_assert (gsi_stmt (*use_stmt_gsi) == use_stmt); + update_stmt (use_stmt); return true; } - /* Now strip away any outer COMPONENT_REF/ARRAY_REF nodes from the LHS. + /* Now strip away any outer COMPONENT_REF/ARRAY_REF nodes from the LHS. ADDR_EXPR will not appear on the LHS. */ - lhsp = &GIMPLE_STMT_OPERAND (use_stmt, 0); - while (handled_component_p (*lhsp)) - lhsp = &TREE_OPERAND (*lhsp, 0); - lhs = *lhsp; + lhs = gimple_assign_lhs (use_stmt); + while (handled_component_p (lhs)) + lhs = TREE_OPERAND (lhs, 0); - /* Now see if the LHS node is an INDIRECT_REF using NAME. If so, + /* Now see if the LHS node is a MEM_REF using NAME. If so, propagate the ADDR_EXPR into the use of NAME and fold the result. */ - if (TREE_CODE (lhs) == INDIRECT_REF - && TREE_OPERAND (lhs, 0) == name - /* This will not allow stripping const qualification from - pointers which we want to allow specifically here to clean up - the IL for initialization of constant objects. */ - && (useless_type_conversion_p (TREE_TYPE (TREE_OPERAND (lhs, 0)), - TREE_TYPE (def_rhs)) - /* So explicitly check for this here. */ - || (TYPE_QUALS (TREE_TYPE (TREE_TYPE (TREE_OPERAND (lhs, 0)))) - ^ TYPE_QUALS (TREE_TYPE (TREE_TYPE (def_rhs)))) == TYPE_QUAL_CONST) - /* ??? This looks redundant, but is required for bogus types - that can sometimes occur. */ - && useless_type_conversion_p (TREE_TYPE (lhs), - TREE_TYPE (TREE_OPERAND (def_rhs, 0)))) + if (TREE_CODE (lhs) == MEM_REF + && TREE_OPERAND (lhs, 0) == name) { - *lhsp = unshare_expr (TREE_OPERAND (def_rhs, 0)); - fold_stmt_inplace (use_stmt); - tidy_after_forward_propagate_addr (use_stmt); - - /* Continue propagating into the RHS if this was not the only use. */ - if (single_use_p) - return true; + tree def_rhs_base; + HOST_WIDE_INT def_rhs_offset; + /* If the address is invariant we can always fold it. */ + if ((def_rhs_base = get_addr_base_and_unit_offset (TREE_OPERAND (def_rhs, 0), + &def_rhs_offset))) + { + double_int off = mem_ref_offset (lhs); + tree new_ptr; + off = double_int_add (off, + shwi_to_double_int (def_rhs_offset)); + if (TREE_CODE (def_rhs_base) == MEM_REF) + { + off = double_int_add (off, mem_ref_offset (def_rhs_base)); + new_ptr = TREE_OPERAND (def_rhs_base, 0); + } + else + new_ptr = build_fold_addr_expr (def_rhs_base); + TREE_OPERAND (lhs, 0) = new_ptr; + TREE_OPERAND (lhs, 1) + = double_int_to_tree (TREE_TYPE (TREE_OPERAND (lhs, 1)), off); + tidy_after_forward_propagate_addr (use_stmt); + /* Continue propagating into the RHS if this was not the only use. */ + if (single_use_p) + return true; + } + /* If the LHS 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. */ + 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, 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 = fold_convert (TREE_TYPE (TREE_OPERAND (lhs, 1)), + TREE_OPERAND (*def_rhs_basep, 1)); + } + else + { + new_base = build_fold_addr_expr (*def_rhs_basep); + new_offset = TREE_OPERAND (lhs, 1); + } + *def_rhs_basep = build2 (MEM_REF, TREE_TYPE (*def_rhs_basep), + new_base, new_offset); + 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 + only use. */ + if (single_use_p) + return true; + } + else + /* We can have a struct assignment dereferencing our name twice. + Note that we didn't propagate into the lhs to not falsely + claim we did when propagating into the rhs. */ + res = false; } /* Strip away any outer COMPONENT_REF, ARRAY_REF or ADDR_EXPR nodes from the RHS. */ - rhsp = &GIMPLE_STMT_OPERAND (use_stmt, 1); - while (handled_component_p (*rhsp) - || TREE_CODE (*rhsp) == ADDR_EXPR) - rhsp = &TREE_OPERAND (*rhsp, 0); - rhs = *rhsp; + rhs = gimple_assign_rhs1 (use_stmt); + if (TREE_CODE (rhs) == ADDR_EXPR) + rhs = TREE_OPERAND (rhs, 0); + while (handled_component_p (rhs)) + rhs = TREE_OPERAND (rhs, 0); - /* Now see if the RHS node is an INDIRECT_REF using NAME. If so, + /* Now see if the RHS node is a MEM_REF using NAME. If so, propagate the ADDR_EXPR into the use of NAME and fold the result. */ - if (TREE_CODE (rhs) == INDIRECT_REF - && TREE_OPERAND (rhs, 0) == name - /* ??? This doesn't allow stripping const qualification to - streamline the IL for reads from non-constant objects. */ - && (useless_type_conversion_p (TREE_TYPE (TREE_OPERAND (rhs, 0)), - TREE_TYPE (def_rhs)) - /* So explicitly check for this here. */ - || (TYPE_QUALS (TREE_TYPE (TREE_TYPE (TREE_OPERAND (rhs, 0)))) - ^ TYPE_QUALS (TREE_TYPE (TREE_TYPE (def_rhs)))) == TYPE_QUAL_CONST) - && useless_type_conversion_p (TREE_TYPE (rhs), - TREE_TYPE (TREE_OPERAND (def_rhs, 0)))) + if (TREE_CODE (rhs) == MEM_REF + && TREE_OPERAND (rhs, 0) == name) { - *rhsp = unshare_expr (TREE_OPERAND (def_rhs, 0)); - fold_stmt_inplace (use_stmt); - tidy_after_forward_propagate_addr (use_stmt); - return true; + tree def_rhs_base; + HOST_WIDE_INT def_rhs_offset; + if ((def_rhs_base = get_addr_base_and_unit_offset (TREE_OPERAND (def_rhs, 0), + &def_rhs_offset))) + { + double_int off = mem_ref_offset (rhs); + tree new_ptr; + off = double_int_add (off, + shwi_to_double_int (def_rhs_offset)); + if (TREE_CODE (def_rhs_base) == MEM_REF) + { + off = double_int_add (off, mem_ref_offset (def_rhs_base)); + new_ptr = TREE_OPERAND (def_rhs_base, 0); + } + else + new_ptr = build_fold_addr_expr (def_rhs_base); + 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_gsi); + tidy_after_forward_propagate_addr (use_stmt); + return res; + } + /* 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 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, 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 = fold_convert (TREE_TYPE (TREE_OPERAND (rhs, 1)), + TREE_OPERAND (*def_rhs_basep, 1)); + } + else + { + new_base = build_fold_addr_expr (*def_rhs_basep); + new_offset = TREE_OPERAND (rhs, 1); + } + *def_rhs_basep = build2 (MEM_REF, TREE_TYPE (*def_rhs_basep), + new_base, new_offset); + 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_gsi); + tidy_after_forward_propagate_addr (use_stmt); + return res; + } } /* If the use of the ADDR_EXPR is not a POINTER_PLUS_EXPR, there is nothing to do. */ - if (TREE_CODE (rhs) != POINTER_PLUS_EXPR - || TREE_OPERAND (rhs, 0) != name) + if (gimple_assign_rhs_code (use_stmt) != POINTER_PLUS_EXPR + || gimple_assign_rhs1 (use_stmt) != name) return false; /* The remaining cases are all for turning pointer arithmetic into @@ -662,49 +1037,43 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, tree use_stmt, element zero in an array. If that is not the case then there is nothing to do. */ array_ref = TREE_OPERAND (def_rhs, 0); - if (TREE_CODE (array_ref) != ARRAY_REF - || TREE_CODE (TREE_TYPE (TREE_OPERAND (array_ref, 0))) != ARRAY_TYPE - || !integer_zerop (TREE_OPERAND (array_ref, 1))) + if ((TREE_CODE (array_ref) != ARRAY_REF + || TREE_CODE (TREE_TYPE (TREE_OPERAND (array_ref, 0))) != ARRAY_TYPE + || TREE_CODE (TREE_OPERAND (array_ref, 1)) != INTEGER_CST) + && TREE_CODE (TREE_TYPE (array_ref)) != ARRAY_TYPE) return false; - /* Try to optimize &x[0] p+ C where C is a multiple of the size - of the elements in X into &x[C/element size]. */ - if (TREE_CODE (TREE_OPERAND (rhs, 1)) == INTEGER_CST) + rhs2 = gimple_assign_rhs2 (use_stmt); + /* Optimize &x[C1] p+ C2 to &x p+ C3 with C3 = C1 * element_size + C2. */ + if (TREE_CODE (rhs2) == INTEGER_CST) { - tree orig = unshare_expr (rhs); - TREE_OPERAND (rhs, 0) = unshare_expr (def_rhs); - - /* If folding succeeds, then we have just exposed new variables - in USE_STMT which will need to be renamed. If folding fails, - then we need to put everything back the way it was. */ - if (fold_stmt_inplace (use_stmt)) - { - tidy_after_forward_propagate_addr (use_stmt); - return true; - } - else - { - GIMPLE_STMT_OPERAND (use_stmt, 1) = orig; - update_stmt (use_stmt); - return false; - } + 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 converting a multiplication of an index by the size of the array elements, then the result is converted into the proper type for the arithmetic. */ - if (TREE_CODE (TREE_OPERAND (rhs, 1)) == SSA_NAME + if (TREE_CODE (rhs2) == SSA_NAME + && (TREE_CODE (array_ref) != ARRAY_REF + || integer_zerop (TREE_OPERAND (array_ref, 1))) + && useless_type_conversion_p (TREE_TYPE (name), TREE_TYPE (def_rhs)) /* Avoid problems with IVopts creating PLUS_EXPRs with a different type than their operands. */ - && useless_type_conversion_p (TREE_TYPE (rhs), TREE_TYPE (name))) - { - bool res; - - res = forward_propagate_addr_into_variable_array_index (TREE_OPERAND (rhs, 1), - def_rhs, use_stmt); - return res; - } + && useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (def_rhs))) + return forward_propagate_addr_into_variable_array_index (rhs2, def_rhs, + use_stmt_gsi); return false; } @@ -718,9 +1087,9 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, tree use_stmt, static bool forward_propagate_addr_expr (tree name, tree rhs) { - int stmt_loop_depth = bb_for_stmt (SSA_NAME_DEF_STMT (name))->loop_depth; + int stmt_loop_depth = gimple_bb (SSA_NAME_DEF_STMT (name))->loop_depth; imm_use_iterator iter; - tree use_stmt; + gimple use_stmt; bool all = true; bool single_use_p = has_single_use (name); @@ -731,48 +1100,57 @@ forward_propagate_addr_expr (tree name, tree rhs) /* If the use is not in a simple assignment statement, then there is nothing we can do. */ - if (TREE_CODE (use_stmt) != GIMPLE_MODIFY_STMT) + if (gimple_code (use_stmt) != GIMPLE_ASSIGN) { - all = false; + if (!is_gimple_debug (use_stmt)) + all = false; continue; } /* If the use is in a deeper loop nest, then we do not want - to propagate the ADDR_EXPR into the loop as that is likely - adding expression evaluations into the loop. */ - if (bb_for_stmt (use_stmt)->loop_depth > stmt_loop_depth) + to propagate non-invariant ADDR_EXPRs into the loop as that + is likely adding expression evaluations into the loop. */ + if (gimple_bb (use_stmt)->loop_depth > stmt_loop_depth + && !is_gimple_min_invariant (rhs)) { all = false; continue; } - push_stmt_changes (&use_stmt); + { + gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt); + result = forward_propagate_addr_expr_1 (name, rhs, &gsi, + single_use_p); + /* If the use has moved to a different statement adjust + the update machinery for the old statement too. */ + if (use_stmt != gsi_stmt (gsi)) + { + update_stmt (use_stmt); + use_stmt = gsi_stmt (gsi); + } - result = forward_propagate_addr_expr_1 (name, rhs, use_stmt, - single_use_p); + update_stmt (use_stmt); + } all &= result; - pop_stmt_changes (&use_stmt); - /* Remove intermediate now unused copy and conversion chains. */ - use_rhs = GIMPLE_STMT_OPERAND (use_stmt, 1); + use_rhs = gimple_assign_rhs1 (use_stmt); if (result - && TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 0)) == SSA_NAME - && (TREE_CODE (use_rhs) == SSA_NAME - || ((TREE_CODE (use_rhs) == NOP_EXPR - || TREE_CODE (use_rhs) == CONVERT_EXPR) - && TREE_CODE (TREE_OPERAND (use_rhs, 0)) == SSA_NAME))) + && TREE_CODE (gimple_assign_lhs (use_stmt)) == SSA_NAME + && TREE_CODE (use_rhs) == SSA_NAME + && has_zero_uses (gimple_assign_lhs (use_stmt))) { - block_stmt_iterator bsi = bsi_for_stmt (use_stmt); + gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt); release_defs (use_stmt); - bsi_remove (&bsi, true); + gsi_remove (&gsi, true); } } - return all; + return all && has_zero_uses (name); } -/* Forward propagate the comparison COND defined in STMT like + +/* Forward propagate the comparison defined in STMT like cond_1 = x CMP y to uses of the form a_1 = (T')cond_1 a_1 = !cond_1 @@ -780,101 +1158,77 @@ forward_propagate_addr_expr (tree name, tree rhs) Returns true if stmt is now unused. */ static bool -forward_propagate_comparison (tree cond, tree stmt) +forward_propagate_comparison (gimple stmt) { - tree name = GIMPLE_STMT_OPERAND (stmt, 0); - tree use_stmt, tmp = NULL_TREE; + 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 (TREE_OPERAND (cond, 0)) == SSA_NAME - && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (TREE_OPERAND (cond, 0))) - || (TREE_CODE (TREE_OPERAND (cond, 1)) == SSA_NAME - && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (TREE_OPERAND (cond, 1)))) + if ((TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME + && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_assign_rhs1 (stmt))) + || (TREE_CODE (gimple_assign_rhs2 (stmt)) == SSA_NAME + && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_assign_rhs2 (stmt)))) return false; /* Do not un-cse comparisons. But propagate through copies. */ use_stmt = get_prop_dest_stmt (name, &name); - if (use_stmt == NULL_TREE) + if (!use_stmt + || !is_gimple_assign (use_stmt)) return false; - /* Conversion of the condition result to another integral type. */ - if (TREE_CODE (use_stmt) == GIMPLE_MODIFY_STMT - && (TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 1)) == CONVERT_EXPR - || TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 1)) == NOP_EXPR - || COMPARISON_CLASS_P (GIMPLE_STMT_OPERAND (use_stmt, 1)) - || TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 1)) == TRUTH_NOT_EXPR) - && INTEGRAL_TYPE_P (TREE_TYPE (GIMPLE_STMT_OPERAND (use_stmt, 0)))) - { - tree lhs = GIMPLE_STMT_OPERAND (use_stmt, 0); - tree rhs = GIMPLE_STMT_OPERAND (use_stmt, 1); - - /* We can propagate the condition into a conversion. */ - if (TREE_CODE (rhs) == CONVERT_EXPR - || TREE_CODE (rhs) == NOP_EXPR) - { - /* Avoid using fold here as that may create a COND_EXPR with - non-boolean condition as canonical form. */ - tmp = build2 (TREE_CODE (cond), TREE_TYPE (lhs), - TREE_OPERAND (cond, 0), TREE_OPERAND (cond, 1)); - } - /* We can propagate the condition into X op CST where op - is EQ_EXRP or NE_EXPR and CST is either one or zero. */ - else if (COMPARISON_CLASS_P (rhs) - && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME - && TREE_CODE (TREE_OPERAND (rhs, 1)) == INTEGER_CST) - { - enum tree_code code = TREE_CODE (rhs); - tree cst = TREE_OPERAND (rhs, 1); - - tmp = combine_cond_expr_cond (code, TREE_TYPE (lhs), - fold_convert (TREE_TYPE (cst), 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 (TREE_CODE (rhs) == TRUTH_NOT_EXPR) - { - tree type = TREE_TYPE (TREE_OPERAND (cond, 0)); - bool nans = HONOR_NANS (TYPE_MODE (type)); - enum tree_code code; - code = invert_tree_comparison (TREE_CODE (cond), 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), TREE_OPERAND (cond, 0), - TREE_OPERAND (cond, 1)); - } - 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_OPERAND (use_stmt, 1) = unshare_expr (tmp); - update_stmt (use_stmt); - - /* Remove defining statements. */ - remove_prop_source_from_use (name, stmt); + tmp = build2 (inv_code, TREE_TYPE (lhs), gimple_assign_rhs1 (stmt), + gimple_assign_rhs2 (stmt)); + } + else + return false; - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, " Replaced '"); - print_generic_expr (dump_file, rhs, dump_flags); - fprintf (dump_file, "' with '"); - print_generic_expr (dump_file, tmp, dump_flags); - fprintf (dump_file, "'\n"); - } + 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); - 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. + propagated. Similarly for negation. - This could trivially be formulated as a forward propagation + This could trivially be formulated as a forward propagation to immediate uses. However, we already had an implementation from DOM which used backward propagation via the use-def links. @@ -882,60 +1236,64 @@ forward_propagate_comparison (tree cond, tree 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 -simplify_not_neg_expr (tree stmt) + Returns true when the statement was changed. */ + +static bool +simplify_not_neg_expr (gimple_stmt_iterator *gsi_p) { - tree rhs = GIMPLE_STMT_OPERAND (stmt, 1); - tree rhs_def_stmt = SSA_NAME_DEF_STMT (TREE_OPERAND (rhs, 0)); + gimple stmt = gsi_stmt (*gsi_p); + tree rhs = gimple_assign_rhs1 (stmt); + gimple rhs_def_stmt = SSA_NAME_DEF_STMT (rhs); /* See if the RHS_DEF_STMT has the same form as our statement. */ - if (TREE_CODE (rhs_def_stmt) == GIMPLE_MODIFY_STMT - && TREE_CODE (GIMPLE_STMT_OPERAND (rhs_def_stmt, 1)) == TREE_CODE (rhs)) + if (is_gimple_assign (rhs_def_stmt) + && gimple_assign_rhs_code (rhs_def_stmt) == gimple_assign_rhs_code (stmt)) { - tree rhs_def_operand = - TREE_OPERAND (GIMPLE_STMT_OPERAND (rhs_def_stmt, 1), 0); + tree rhs_def_operand = gimple_assign_rhs1 (rhs_def_stmt); /* Verify that RHS_DEF_OPERAND is a suitable SSA_NAME. */ if (TREE_CODE (rhs_def_operand) == SSA_NAME && ! SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rhs_def_operand)) { - GIMPLE_STMT_OPERAND (stmt, 1) = rhs_def_operand; + 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 -simplify_switch_expr (tree stmt) +static bool +simplify_gimple_switch (gimple stmt) { - tree cond = SWITCH_COND (stmt); + tree cond = gimple_switch_index (stmt); tree def, to, ti; + gimple def_stmt; /* The optimization that we really care about is removing unnecessary casts. That will let us do much better in propagating the inferred constant at the switch target. */ if (TREE_CODE (cond) == SSA_NAME) { - def = SSA_NAME_DEF_STMT (cond); - if (TREE_CODE (def) == GIMPLE_MODIFY_STMT) + def_stmt = SSA_NAME_DEF_STMT (cond); + if (is_gimple_assign (def_stmt)) { - def = GIMPLE_STMT_OPERAND (def, 1); - if (TREE_CODE (def) == NOP_EXPR) + if (gimple_assign_rhs_code (def_stmt) == NOP_EXPR) { int need_precision; bool fail; - def = TREE_OPERAND (def, 0); + 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); @@ -956,121 +1314,1257 @@ simplify_switch_expr (tree stmt) if (!fail) { - SWITCH_COND (stmt) = def; + gimple_switch_set_index (stmt, def); update_stmt (stmt); + return true; } } } } + + return false; } -/* Main entry point for the forward propagation optimizer. */ +/* For pointers p2 and p1 return p2 - p1 if the + difference is known and constant, otherwise return NULL. */ -static unsigned int -tree_ssa_forward_propagate_single_use_vars (void) +static tree +constant_pointer_difference (tree p1, tree p2) { - basic_block bb; - unsigned int todoflags = 0; + int i, j; +#define CPD_ITERATIONS 5 + tree exps[2][CPD_ITERATIONS]; + tree offs[2][CPD_ITERATIONS]; + int cnt[2]; - cfg_changed = false; - - FOR_EACH_BB (bb) + for (i = 0; i < 2; i++) { - block_stmt_iterator bsi; - - /* Note we update BSI within the loop as necessary. */ - for (bsi = bsi_start (bb); !bsi_end_p (bsi); ) + 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 { - tree stmt = bsi_stmt (bsi); - - /* If this statement sets an SSA_NAME to an address, - try to propagate the address into the uses of the SSA_NAME. */ - if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT) + if (!POINTER_TYPE_P (TREE_TYPE (p))) + break; + if (TREE_CODE (p) == ADDR_EXPR) { - tree lhs = GIMPLE_STMT_OPERAND (stmt, 0); - tree rhs = GIMPLE_STMT_OPERAND (stmt, 1); - - - if (TREE_CODE (lhs) != SSA_NAME) + tree q = TREE_OPERAND (p, 0); + HOST_WIDE_INT offset; + tree base = get_addr_base_and_unit_offset (q, &offset); + if (base) { - bsi_next (&bsi); - continue; + q = base; + if (offset) + off = size_binop (PLUS_EXPR, off, size_int (offset)); } - - if (TREE_CODE (rhs) == ADDR_EXPR - /* Handle pointer conversions on invariant addresses - as well, as this is valid gimple. */ - || ((TREE_CODE (rhs) == NOP_EXPR - || TREE_CODE (rhs) == CONVERT_EXPR) - && TREE_CODE (TREE_OPERAND (rhs, 0)) == ADDR_EXPR - && POINTER_TYPE_P (TREE_TYPE (rhs)))) + if (TREE_CODE (q) == MEM_REF + && TREE_CODE (TREE_OPERAND (q, 0)) == SSA_NAME) { - STRIP_NOPS (rhs); - if (!stmt_references_abnormal_ssa_name (stmt) - && forward_propagate_addr_expr (lhs, rhs)) - { - release_defs (stmt); - todoflags |= TODO_remove_unused_locals; - bsi_remove (&bsi, true); - } - else - bsi_next (&bsi); + p = TREE_OPERAND (q, 0); + off = size_binop (PLUS_EXPR, off, + double_int_to_tree (sizetype, + mem_ref_offset (q))); } - else if ((TREE_CODE (rhs) == BIT_NOT_EXPR - || TREE_CODE (rhs) == NEGATE_EXPR) - && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME) + 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; + + def1_code = TREE_CODE (arg1); + def1_arg1 = arg1; + if (TREE_CODE (arg1) == SSA_NAME) + { + def1 = SSA_NAME_DEF_STMT (arg1); + if (is_gimple_assign (def1)) + { + def1_code = gimple_assign_rhs_code (def1); + def1_arg1 = gimple_assign_rhs1 (def1); + } + } + + 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)) + { + def2_code = gimple_assign_rhs_code (def2); + def2_arg1 = gimple_assign_rhs1 (def2); + } + } + + /* 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; + } + + /* 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) { - simplify_not_neg_expr (stmt); - bsi_next (&bsi); + /* 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 (rhs) == COND_EXPR) - { - int did_something; - fold_defer_overflow_warnings (); - did_something = forward_propagate_into_cond (rhs, stmt); - if (did_something == 2) - cfg_changed = true; - fold_undefer_overflow_warnings (!TREE_NO_WARNING (rhs) - && did_something, stmt, WARN_STRICT_OVERFLOW_CONDITIONAL); - bsi_next (&bsi); - } - else if (COMPARISON_CLASS_P (rhs)) + else if (TREE_CODE (rhs1) == INTEGER_CST + && TREE_CODE (def_rhs1) == INTEGER_CST) { - if (forward_propagate_comparison (rhs, stmt)) + /* CST +- (CST +- A) -> CST +- A. */ + tree cst = fold_binary (code, TREE_TYPE (rhs2), + rhs1, def_rhs1); + if (cst && !TREE_OVERFLOW (cst)) { - release_defs (stmt); - todoflags |= TODO_remove_unused_locals; - bsi_remove (&bsi, true); + 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 - bsi_next (&bsi); + } + 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 false; +} + +/* 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 +ssa_forward_propagate_and_combine (void) +{ + basic_block bb; + unsigned int todoflags = 0; + + cfg_changed = false; + + FOR_EACH_BB (bb) + { + gimple_stmt_iterator gsi, prev; + bool prev_initialized; + + /* 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 (!is_gimple_assign (stmt)) + { + 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 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)) + { + release_defs (stmt); + todoflags |= TODO_remove_unused_locals; + gsi_remove (&gsi, true); + } + 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, + off))))) + { + 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 (&gsi); + update_stmt (stmt); + if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR) + gsi_next (&gsi); } else - bsi_next (&bsi); + gsi_next (&gsi); } - else if (TREE_CODE (stmt) == SWITCH_EXPR) + else if (TREE_CODE_CLASS (code) == tcc_comparison) { - simplify_switch_expr (stmt); - bsi_next (&bsi); + if (forward_propagate_comparison (stmt)) + cfg_changed = true; + gsi_next (&gsi); } - else if (TREE_CODE (stmt) == COND_EXPR) + 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)) { - int did_something; - fold_defer_overflow_warnings (); - did_something = forward_propagate_into_cond (stmt, stmt); - if (did_something == 2) - cfg_changed = true; - fold_undefer_overflow_warnings (did_something, stmt, - WARN_STRICT_OVERFLOW_CONDITIONAL); - bsi_next (&bsi); + 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) + { + /* 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 - bsi_next (&bsi); + { + prev = gsi; + prev_initialized = true; + gsi_next (&gsi); + } } } if (cfg_changed) todoflags |= TODO_cleanup_cfg; + return todoflags; } @@ -1078,13 +2572,16 @@ tree_ssa_forward_propagate_single_use_vars (void) static bool gate_forwprop (void) { - return 1; + return flag_tree_forwprop; } -struct tree_opt_pass pass_forwprop = { +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 */ @@ -1093,10 +2590,8 @@ struct tree_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 */ - 0 /* letter */ + | TODO_verify_ssa /* todo_flags_finish */ + } }; -