/* Forward propagation of expressions for single use variables.
- Copyright (C) 2004, 2005, 2007, 2008, 2009 Free Software Foundation, Inc.
+ Copyright (C) 2004, 2005, 2007, 2008, 2009, 2010, 2011
+ Free Software Foundation, Inc.
This file is part of GCC.
#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
static bool
can_propagate_from (gimple def_stmt)
{
- use_operand_p use_p;
- ssa_op_iter iter;
-
gcc_assert (is_gimple_assign (def_stmt));
/* If the rhs has side-effects we cannot propagate from it. */
return true;
/* We cannot propagate ssa names that occur in abnormal phi nodes. */
- FOR_EACH_SSA_USE_OPERAND (use_p, def_stmt, iter, SSA_OP_USE)
- if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (USE_FROM_PTR (use_p)))
- return false;
+ if (stmt_references_abnormal_ssa_name (def_stmt))
+ return false;
/* If the definition is a conversion of a pointer to a function type,
then we can not apply optimizations as some targets require
return true;
}
-/* Remove a copy chain ending in NAME along the defs but not
- further or including UP_TO_STMT. If NAME was replaced in
- its only use then this function can be used to clean up
- dead stmts. Returns true if UP_TO_STMT can be removed
- as well, otherwise false. */
+/* Remove a chain of dead statements starting at the definition of
+ NAME. The chain is linked via the first operand of the defining statements.
+ If NAME was replaced in its only use then this function can be used
+ to clean up dead stmts. The function handles already released SSA
+ names gracefully.
+ Returns true if cleanup-cfg has to run. */
static bool
-remove_prop_source_from_use (tree name, gimple up_to_stmt)
+remove_prop_source_from_use (tree name)
{
gimple_stmt_iterator gsi;
gimple stmt;
+ bool cfg_changed = false;
do {
- if (!has_zero_uses (name))
- return false;
+ basic_block bb;
+
+ if (SSA_NAME_IN_FREE_LIST (name)
+ || SSA_NAME_IS_DEFAULT_DEF (name)
+ || !has_zero_uses (name))
+ return cfg_changed;
stmt = SSA_NAME_DEF_STMT (name);
- if (stmt == up_to_stmt)
- return true;
+ if (gimple_code (stmt) == GIMPLE_PHI
+ || gimple_has_side_effects (stmt))
+ return cfg_changed;
+ bb = gimple_bb (stmt);
gsi = gsi_for_stmt (stmt);
- release_defs (stmt);
+ unlink_stmt_vdef (stmt);
gsi_remove (&gsi, true);
+ release_defs (stmt);
+ cfg_changed |= gimple_purge_dead_eh_edges (bb);
- name = (gimple_assign_copy_p (stmt)) ? gimple_assign_rhs1 (stmt) : NULL;
+ name = is_gimple_assign (stmt) ? gimple_assign_rhs1 (stmt) : NULL_TREE;
} while (name && TREE_CODE (name) == SSA_NAME);
- return false;
+ return cfg_changed;
}
/* Return the rhs of a gimple_assign STMT in a form of a single tree,
{
location_t loc = gimple_location (stmt);
enum tree_code code = gimple_assign_rhs_code (stmt);
- if (get_gimple_rhs_class (code) == GIMPLE_BINARY_RHS)
+ if (get_gimple_rhs_class (code) == GIMPLE_TERNARY_RHS)
+ return fold_build3_loc (loc, code, type, gimple_assign_rhs1 (stmt),
+ gimple_assign_rhs2 (stmt),
+ gimple_assign_rhs3 (stmt));
+ else if (get_gimple_rhs_class (code) == GIMPLE_BINARY_RHS)
return fold_build2_loc (loc, code, type, gimple_assign_rhs1 (stmt),
gimple_assign_rhs2 (stmt));
else if (get_gimple_rhs_class (code) == GIMPLE_UNARY_RHS)
considered simplified. */
static tree
-combine_cond_expr_cond (location_t loc, enum tree_code code, tree type,
+combine_cond_expr_cond (gimple stmt, enum tree_code code, tree type,
tree op0, tree op1, bool invariant_only)
{
tree t;
gcc_assert (TREE_CODE_CLASS (code) == tcc_comparison);
- t = fold_binary_loc (loc, code, type, op0, op1);
+ fold_defer_overflow_warnings ();
+ t = fold_binary_loc (gimple_location (stmt), code, type, op0, op1);
if (!t)
- return NULL_TREE;
+ {
+ fold_undefer_overflow_warnings (false, NULL, 0);
+ return NULL_TREE;
+ }
/* Require that we got a boolean type out if we put one in. */
gcc_assert (TREE_CODE (TREE_TYPE (t)) == TREE_CODE (type));
/* Bail out if we required an invariant but didn't get one. */
if (!t || (invariant_only && !is_gimple_min_invariant (t)))
- return NULL_TREE;
+ {
+ fold_undefer_overflow_warnings (false, NULL, 0);
+ return NULL_TREE;
+ }
+
+ fold_undefer_overflow_warnings (!gimple_no_warning_p (stmt), stmt, 0);
return t;
}
+/* Combine the comparison OP0 CODE OP1 at LOC with the defining statements
+ of its operand. Return a new comparison tree or NULL_TREE if there
+ were no simplifying combines. */
+
+static tree
+forward_propagate_into_comparison_1 (gimple stmt,
+ enum tree_code code, tree type,
+ tree op0, tree op1)
+{
+ tree tmp = NULL_TREE;
+ tree rhs0 = NULL_TREE, rhs1 = NULL_TREE;
+ bool single_use0_p = false, single_use1_p = false;
+
+ /* For comparisons use the first operand, that is likely to
+ simplify comparisons against constants. */
+ if (TREE_CODE (op0) == SSA_NAME)
+ {
+ gimple def_stmt = get_prop_source_stmt (op0, false, &single_use0_p);
+ if (def_stmt && can_propagate_from (def_stmt))
+ {
+ rhs0 = rhs_to_tree (TREE_TYPE (op1), def_stmt);
+ tmp = combine_cond_expr_cond (stmt, code, type,
+ rhs0, op1, !single_use0_p);
+ if (tmp)
+ return tmp;
+ }
+ }
+
+ /* If that wasn't successful, try the second operand. */
+ if (TREE_CODE (op1) == SSA_NAME)
+ {
+ gimple def_stmt = get_prop_source_stmt (op1, false, &single_use1_p);
+ if (def_stmt && can_propagate_from (def_stmt))
+ {
+ rhs1 = rhs_to_tree (TREE_TYPE (op0), def_stmt);
+ tmp = combine_cond_expr_cond (stmt, code, type,
+ op0, rhs1, !single_use1_p);
+ if (tmp)
+ return tmp;
+ }
+ }
+
+ /* If that wasn't successful either, try both operands. */
+ if (rhs0 != NULL_TREE
+ && rhs1 != NULL_TREE)
+ tmp = combine_cond_expr_cond (stmt, code, type,
+ rhs0, rhs1,
+ !(single_use0_p && single_use1_p));
+
+ return tmp;
+}
+
+/* Propagate from the ssa name definition statements of the assignment
+ from a comparison at *GSI into the conditional if that simplifies it.
+ Returns 1 if the stmt was modified and 2 if the CFG needs cleanup,
+ otherwise returns 0. */
+
+static int
+forward_propagate_into_comparison (gimple_stmt_iterator *gsi)
+{
+ gimple stmt = gsi_stmt (*gsi);
+ tree tmp;
+ bool cfg_changed = false;
+ tree type = TREE_TYPE (gimple_assign_lhs (stmt));
+ tree rhs1 = gimple_assign_rhs1 (stmt);
+ tree rhs2 = gimple_assign_rhs2 (stmt);
+
+ /* Combine the comparison with defining statements. */
+ tmp = forward_propagate_into_comparison_1 (stmt,
+ gimple_assign_rhs_code (stmt),
+ type, rhs1, rhs2);
+ if (tmp && useless_type_conversion_p (type, TREE_TYPE (tmp)))
+ {
+ gimple_assign_set_rhs_from_tree (gsi, tmp);
+ fold_stmt (gsi);
+ update_stmt (gsi_stmt (*gsi));
+
+ if (TREE_CODE (rhs1) == SSA_NAME)
+ cfg_changed |= remove_prop_source_from_use (rhs1);
+ if (TREE_CODE (rhs2) == SSA_NAME)
+ cfg_changed |= remove_prop_source_from_use (rhs2);
+ return cfg_changed ? 2 : 1;
+ }
+
+ return 0;
+}
+
/* Propagate from the ssa name definition statements of COND_EXPR
in GIMPLE_COND statement STMT into the conditional if that simplifies it.
Returns zero if no statement was changed, one if there were
static int
forward_propagate_into_gimple_cond (gimple stmt)
{
- int did_something = 0;
- location_t loc = gimple_location (stmt);
-
- do {
- tree tmp = NULL_TREE;
- tree name = NULL_TREE, rhs0 = NULL_TREE, rhs1 = NULL_TREE;
- gimple def_stmt;
- bool single_use0_p = false, single_use1_p = false;
- enum tree_code code = gimple_cond_code (stmt);
-
- /* We can do tree combining on SSA_NAME and comparison expressions. */
- if (TREE_CODE_CLASS (gimple_cond_code (stmt)) == tcc_comparison)
- {
- /* For comparisons use the first operand, that is likely to
- simplify comparisons against constants. */
- if (TREE_CODE (gimple_cond_lhs (stmt)) == SSA_NAME)
- {
- name = gimple_cond_lhs (stmt);
- def_stmt = get_prop_source_stmt (name, false, &single_use0_p);
- if (def_stmt && can_propagate_from (def_stmt))
- {
- tree op1 = gimple_cond_rhs (stmt);
- rhs0 = rhs_to_tree (TREE_TYPE (op1), def_stmt);
- tmp = combine_cond_expr_cond (loc, code, boolean_type_node,
- rhs0, op1, !single_use0_p);
- }
- }
- /* If that wasn't successful, try the second operand. */
- if (tmp == NULL_TREE
- && TREE_CODE (gimple_cond_rhs (stmt)) == SSA_NAME)
- {
- tree op0 = gimple_cond_lhs (stmt);
- name = gimple_cond_rhs (stmt);
- def_stmt = get_prop_source_stmt (name, false, &single_use1_p);
- if (!def_stmt || !can_propagate_from (def_stmt))
- return did_something;
-
- rhs1 = rhs_to_tree (TREE_TYPE (op0), def_stmt);
- tmp = combine_cond_expr_cond (loc, code, boolean_type_node, op0,
- rhs1, !single_use1_p);
- }
- /* If that wasn't successful either, try both operands. */
- if (tmp == NULL_TREE
- && rhs0 != NULL_TREE
- && rhs1 != NULL_TREE)
- tmp = combine_cond_expr_cond (loc, code, boolean_type_node, rhs0,
- fold_convert_loc (loc,
- TREE_TYPE (rhs0),
- rhs1),
- !(single_use0_p && single_use1_p));
- }
-
- if (tmp)
- {
- if (dump_file && tmp)
- {
- tree cond = build2 (gimple_cond_code (stmt),
- boolean_type_node,
- gimple_cond_lhs (stmt),
- gimple_cond_rhs (stmt));
- fprintf (dump_file, " Replaced '");
- print_generic_expr (dump_file, cond, 0);
- fprintf (dump_file, "' with '");
- print_generic_expr (dump_file, tmp, 0);
- fprintf (dump_file, "'\n");
- }
-
- gimple_cond_set_condition_from_tree (stmt, unshare_expr (tmp));
- update_stmt (stmt);
-
- /* Remove defining statements. */
- remove_prop_source_from_use (name, NULL);
+ tree tmp;
+ enum tree_code code = gimple_cond_code (stmt);
+ bool cfg_changed = false;
+ tree rhs1 = gimple_cond_lhs (stmt);
+ tree rhs2 = gimple_cond_rhs (stmt);
+
+ /* We can do tree combining on SSA_NAME and comparison expressions. */
+ if (TREE_CODE_CLASS (gimple_cond_code (stmt)) != tcc_comparison)
+ return 0;
+
+ tmp = forward_propagate_into_comparison_1 (stmt, code,
+ boolean_type_node,
+ rhs1, rhs2);
+ if (tmp)
+ {
+ if (dump_file && tmp)
+ {
+ fprintf (dump_file, " Replaced '");
+ print_gimple_expr (dump_file, stmt, 0, 0);
+ fprintf (dump_file, "' with '");
+ print_generic_expr (dump_file, tmp, 0);
+ fprintf (dump_file, "'\n");
+ }
- if (is_gimple_min_invariant (tmp))
- did_something = 2;
- else if (did_something == 0)
- did_something = 1;
+ gimple_cond_set_condition_from_tree (stmt, unshare_expr (tmp));
+ update_stmt (stmt);
- /* Continue combining. */
- continue;
- }
+ if (TREE_CODE (rhs1) == SSA_NAME)
+ cfg_changed |= remove_prop_source_from_use (rhs1);
+ if (TREE_CODE (rhs2) == SSA_NAME)
+ cfg_changed |= remove_prop_source_from_use (rhs2);
+ return (cfg_changed || is_gimple_min_invariant (tmp)) ? 2 : 1;
+ }
- break;
- } while (1);
+ /* Canonicalize _Bool == 0 and _Bool != 1 to _Bool != 0 by swapping edges. */
+ if ((TREE_CODE (TREE_TYPE (rhs1)) == BOOLEAN_TYPE
+ || (INTEGRAL_TYPE_P (TREE_TYPE (rhs1))
+ && TYPE_PRECISION (TREE_TYPE (rhs1)) == 1))
+ && ((code == EQ_EXPR
+ && integer_zerop (rhs2))
+ || (code == NE_EXPR
+ && integer_onep (rhs2))))
+ {
+ basic_block bb = gimple_bb (stmt);
+ gimple_cond_set_code (stmt, NE_EXPR);
+ gimple_cond_set_rhs (stmt, build_zero_cst (TREE_TYPE (rhs1)));
+ EDGE_SUCC (bb, 0)->flags ^= (EDGE_TRUE_VALUE|EDGE_FALSE_VALUE);
+ EDGE_SUCC (bb, 1)->flags ^= (EDGE_TRUE_VALUE|EDGE_FALSE_VALUE);
+ return 1;
+ }
- return did_something;
+ return 0;
}
/* Propagate from the ssa name definition statements of COND_EXPR
in the rhs of statement STMT into the conditional if that simplifies it.
- Returns zero if no statement was changed, one if there were
- changes and two if cfg_cleanup needs to run.
+ Returns true zero if the stmt was changed. */
- This must be kept in sync with forward_propagate_into_gimple_cond. */
-
-static int
+static bool
forward_propagate_into_cond (gimple_stmt_iterator *gsi_p)
{
gimple stmt = gsi_stmt (*gsi_p);
- location_t loc = gimple_location (stmt);
- int did_something = 0;
-
- do {
- tree tmp = NULL_TREE;
- tree cond = gimple_assign_rhs1 (stmt);
- tree name, rhs0 = NULL_TREE, rhs1 = NULL_TREE;
- gimple def_stmt;
- bool single_use0_p = false, single_use1_p = false;
-
- /* We can do tree combining on SSA_NAME and comparison expressions. */
- if (COMPARISON_CLASS_P (cond)
- && TREE_CODE (TREE_OPERAND (cond, 0)) == SSA_NAME)
- {
- /* For comparisons use the first operand, that is likely to
- simplify comparisons against constants. */
- name = TREE_OPERAND (cond, 0);
- def_stmt = get_prop_source_stmt (name, false, &single_use0_p);
- if (def_stmt && can_propagate_from (def_stmt))
- {
- tree op1 = TREE_OPERAND (cond, 1);
- rhs0 = rhs_to_tree (TREE_TYPE (op1), def_stmt);
- tmp = combine_cond_expr_cond (loc, TREE_CODE (cond),
- boolean_type_node,
- rhs0, op1, !single_use0_p);
- }
- /* If that wasn't successful, try the second operand. */
- if (tmp == NULL_TREE
- && TREE_CODE (TREE_OPERAND (cond, 1)) == SSA_NAME)
- {
- tree op0 = TREE_OPERAND (cond, 0);
- name = TREE_OPERAND (cond, 1);
- def_stmt = get_prop_source_stmt (name, false, &single_use1_p);
- if (!def_stmt || !can_propagate_from (def_stmt))
- return did_something;
-
- rhs1 = rhs_to_tree (TREE_TYPE (op0), def_stmt);
- tmp = combine_cond_expr_cond (loc, TREE_CODE (cond),
- boolean_type_node,
- op0, rhs1, !single_use1_p);
- }
- /* If that wasn't successful either, try both operands. */
- if (tmp == NULL_TREE
- && rhs0 != NULL_TREE
- && rhs1 != NULL_TREE)
- tmp = combine_cond_expr_cond (loc, TREE_CODE (cond),
- boolean_type_node,
- rhs0,
- fold_convert_loc (loc,
- TREE_TYPE (rhs0),
- rhs1),
- !(single_use0_p && single_use1_p));
- }
- else if (TREE_CODE (cond) == SSA_NAME)
- {
- name = cond;
- def_stmt = get_prop_source_stmt (name, true, NULL);
- if (def_stmt || !can_propagate_from (def_stmt))
- return did_something;
-
- rhs0 = gimple_assign_rhs1 (def_stmt);
- tmp = combine_cond_expr_cond (loc, NE_EXPR, boolean_type_node, rhs0,
- build_int_cst (TREE_TYPE (rhs0), 0),
- false);
- }
-
- if (tmp)
- {
- if (dump_file && tmp)
- {
- fprintf (dump_file, " Replaced '");
- print_generic_expr (dump_file, cond, 0);
- fprintf (dump_file, "' with '");
- print_generic_expr (dump_file, tmp, 0);
- fprintf (dump_file, "'\n");
- }
-
- gimple_assign_set_rhs_from_tree (gsi_p, unshare_expr (tmp));
- stmt = gsi_stmt (*gsi_p);
- update_stmt (stmt);
-
- /* Remove defining statements. */
- remove_prop_source_from_use (name, NULL);
+ tree tmp = NULL_TREE;
+ tree cond = gimple_assign_rhs1 (stmt);
+ bool swap = false;
+
+ /* We can do tree combining on SSA_NAME and comparison expressions. */
+ if (COMPARISON_CLASS_P (cond))
+ tmp = forward_propagate_into_comparison_1 (stmt, TREE_CODE (cond),
+ boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1));
+ else if (TREE_CODE (cond) == SSA_NAME)
+ {
+ enum tree_code code;
+ tree name = cond;
+ gimple def_stmt = get_prop_source_stmt (name, true, NULL);
+ if (!def_stmt || !can_propagate_from (def_stmt))
+ return 0;
+
+ code = gimple_assign_rhs_code (def_stmt);
+ if (TREE_CODE_CLASS (code) == tcc_comparison)
+ tmp = fold_build2_loc (gimple_location (def_stmt),
+ code,
+ boolean_type_node,
+ gimple_assign_rhs1 (def_stmt),
+ gimple_assign_rhs2 (def_stmt));
+ else if ((code == BIT_NOT_EXPR
+ && TYPE_PRECISION (TREE_TYPE (cond)) == 1)
+ || (code == BIT_XOR_EXPR
+ && integer_onep (gimple_assign_rhs2 (def_stmt))))
+ {
+ tmp = gimple_assign_rhs1 (def_stmt);
+ swap = true;
+ }
+ }
- if (is_gimple_min_invariant (tmp))
- did_something = 2;
- else if (did_something == 0)
- did_something = 1;
+ if (tmp
+ && is_gimple_condexpr (tmp))
+ {
+ if (dump_file && tmp)
+ {
+ fprintf (dump_file, " Replaced '");
+ print_generic_expr (dump_file, cond, 0);
+ fprintf (dump_file, "' with '");
+ print_generic_expr (dump_file, tmp, 0);
+ fprintf (dump_file, "'\n");
+ }
- /* Continue combining. */
- continue;
- }
+ if (integer_onep (tmp))
+ gimple_assign_set_rhs_from_tree (gsi_p, gimple_assign_rhs2 (stmt));
+ else if (integer_zerop (tmp))
+ gimple_assign_set_rhs_from_tree (gsi_p, gimple_assign_rhs3 (stmt));
+ else
+ {
+ gimple_assign_set_rhs1 (stmt, unshare_expr (tmp));
+ if (swap)
+ {
+ tree t = gimple_assign_rhs2 (stmt);
+ gimple_assign_set_rhs2 (stmt, gimple_assign_rhs3 (stmt));
+ gimple_assign_set_rhs3 (stmt, t);
+ }
+ }
+ stmt = gsi_stmt (*gsi_p);
+ update_stmt (stmt);
- break;
- } while (1);
+ return true;
+ }
- return did_something;
+ return 0;
}
/* We've just substituted an ADDR_EXPR into stmt. Update all the
{
tree index, tunit;
gimple offset_def, use_stmt = gsi_stmt (*use_stmt_gsi);
- tree tmp;
+ tree new_rhs, tmp;
- tunit = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (def_rhs)));
+ 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;
/* Replace the pointer addition with array indexing. */
index = force_gimple_operand_gsi (use_stmt_gsi, index, true, NULL_TREE,
true, GSI_SAME_STMT);
- gimple_assign_set_rhs_from_tree (use_stmt_gsi, unshare_expr (def_rhs));
- use_stmt = gsi_stmt (*use_stmt_gsi);
- TREE_OPERAND (TREE_OPERAND (gimple_assign_rhs1 (use_stmt), 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);
+ 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;
}
bool single_use_p)
{
tree lhs, rhs, rhs2, array_ref;
- tree *rhsp, *lhsp;
gimple use_stmt = gsi_stmt (*use_stmt_gsi);
enum tree_code rhs_code;
bool res = true;
- bool addr_p = false;
gcc_assert (TREE_CODE (def_rhs) == ADDR_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.
ADDR_EXPR will not appear on the LHS. */
- lhsp = gimple_assign_lhs_ptr (use_stmt);
- 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
+ if (TREE_CODE (lhs) == MEM_REF
&& TREE_OPERAND (lhs, 0) == name)
{
- if (may_propagate_address_into_dereference (def_rhs, lhs)
- && (lhsp != gimple_assign_lhs_ptr (use_stmt)
- || useless_type_conversion_p
- (TREE_TYPE (TREE_OPERAND (def_rhs, 0)), TREE_TYPE (rhs))))
+ 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)))
{
- *lhsp = unshare_expr (TREE_OPERAND (def_rhs, 0));
- fold_stmt_inplace (use_stmt);
+ 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
/* Strip away any outer COMPONENT_REF, ARRAY_REF or ADDR_EXPR
nodes from the RHS. */
- rhsp = gimple_assign_rhs1_ptr (use_stmt);
- if (TREE_CODE (*rhsp) == ADDR_EXPR)
- {
- rhsp = &TREE_OPERAND (*rhsp, 0);
- addr_p = true;
- }
- while (handled_component_p (*rhsp))
- 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
- && may_propagate_address_into_dereference (def_rhs, rhs))
+ 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 res;
+ 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;
+ }
}
- /* Now see if the RHS node is an INDIRECT_REF using NAME. If so,
- propagate the ADDR_EXPR into the use of NAME and try to
- create a VCE and fold the result. */
- if (TREE_CODE (rhs) == INDIRECT_REF
- && TREE_OPERAND (rhs, 0) == name
- && TYPE_SIZE (TREE_TYPE (rhs))
- && TYPE_SIZE (TREE_TYPE (TREE_OPERAND (def_rhs, 0)))
- /* Function decls should not be used for VCE either as it could be a
- function descriptor that we want and not the actual function code. */
- && TREE_CODE (TREE_OPERAND (def_rhs, 0)) != FUNCTION_DECL
- /* We should not convert volatile loads to non volatile loads. */
- && !TYPE_VOLATILE (TREE_TYPE (rhs))
- && !TYPE_VOLATILE (TREE_TYPE (TREE_OPERAND (def_rhs, 0)))
- && operand_equal_p (TYPE_SIZE (TREE_TYPE (rhs)),
- TYPE_SIZE (TREE_TYPE (TREE_OPERAND (def_rhs, 0))), 0)
- /* Make sure we only do TBAA compatible replacements. */
- && get_alias_set (TREE_OPERAND (def_rhs, 0)) == get_alias_set (rhs))
- {
- tree def_rhs_base, new_rhs = unshare_expr (TREE_OPERAND (def_rhs, 0));
- new_rhs = fold_build1 (VIEW_CONVERT_EXPR, TREE_TYPE (rhs), new_rhs);
- if (TREE_CODE (new_rhs) != VIEW_CONVERT_EXPR)
- {
- /* If we have folded the VIEW_CONVERT_EXPR then the result is only
- valid if we can replace the whole rhs of the use statement. */
- if (rhs != gimple_assign_rhs1 (use_stmt))
- return false;
- new_rhs = force_gimple_operand_gsi (use_stmt_gsi, new_rhs, true, NULL,
- true, GSI_NEW_STMT);
- gimple_assign_set_rhs1 (use_stmt, new_rhs);
- tidy_after_forward_propagate_addr (use_stmt);
- return res;
- }
- /* If the defining rhs comes from an indirect reference, then do not
- convert into a VIEW_CONVERT_EXPR. Likewise if we'll end up taking
- the address of a V_C_E of a constant. */
- def_rhs_base = TREE_OPERAND (def_rhs, 0);
- while (handled_component_p (def_rhs_base))
- def_rhs_base = TREE_OPERAND (def_rhs_base, 0);
- if (!INDIRECT_REF_P (def_rhs_base)
- && (!addr_p
- || !is_gimple_min_invariant (def_rhs)))
- {
- /* We may have arbitrary VIEW_CONVERT_EXPRs in a nested component
- reference. Place it there and fold the thing. */
- *rhsp = new_rhs;
- fold_stmt_inplace (use_stmt);
- 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 (gimple_assign_rhs_code (use_stmt) != POINTER_PLUS_EXPR
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
- || TREE_CODE (TREE_OPERAND (array_ref, 1)) != INTEGER_CST)
+ 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;
rhs2 = gimple_assign_rhs2 (use_stmt);
- /* Try to optimize &x[C1] p+ C2 where C2 is a multiple of the size
- of the elements in X into &x[C1 + C2/element size]. */
+ /* Optimize &x[C1] p+ C2 to &x p+ C3 with C3 = C1 * element_size + C2. */
if (TREE_CODE (rhs2) == INTEGER_CST)
{
- tree new_rhs = maybe_fold_stmt_addition (gimple_location (use_stmt),
- TREE_TYPE (def_rhs),
- def_rhs, rhs2);
- if (new_rhs)
- {
- tree type = TREE_TYPE (gimple_assign_lhs (use_stmt));
- new_rhs = unshare_expr (new_rhs);
- if (!useless_type_conversion_p (type, TREE_TYPE (new_rhs)))
- {
- if (!is_gimple_min_invariant (new_rhs))
- new_rhs = force_gimple_operand_gsi (use_stmt_gsi, new_rhs,
- true, NULL_TREE,
- true, GSI_SAME_STMT);
- new_rhs = fold_convert (type, new_rhs);
- }
- gimple_assign_set_rhs_from_tree (use_stmt_gsi, new_rhs);
- use_stmt = gsi_stmt (*use_stmt_gsi);
- update_stmt (use_stmt);
- tidy_after_forward_propagate_addr (use_stmt);
- return true;
- }
+ tree new_rhs = build1_loc (gimple_location (use_stmt),
+ ADDR_EXPR, TREE_TYPE (def_rhs),
+ fold_build2 (MEM_REF,
+ TREE_TYPE (TREE_TYPE (def_rhs)),
+ unshare_expr (def_rhs),
+ fold_convert (ptr_type_node,
+ rhs2)));
+ gimple_assign_set_rhs_from_tree (use_stmt_gsi, new_rhs);
+ use_stmt = gsi_stmt (*use_stmt_gsi);
+ update_stmt (use_stmt);
+ tidy_after_forward_propagate_addr (use_stmt);
+ return true;
}
/* Try to optimize &x[0] p+ OFFSET where OFFSET is defined by
array elements, then the result is converted into the proper
type for the arithmetic. */
if (TREE_CODE (rhs2) == SSA_NAME
- && integer_zerop (TREE_OPERAND (array_ref, 1))
+ && (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. */
}
}
- return all;
+ return all && has_zero_uses (name);
}
+
/* Forward propagate the comparison defined in STMT like
cond_1 = x CMP y to uses of the form
a_1 = (T')cond_1
tree name = gimple_assign_lhs (stmt);
gimple use_stmt;
tree tmp = NULL_TREE;
+ gimple_stmt_iterator gsi;
+ enum tree_code code;
+ tree lhs;
/* Don't propagate ssa names that occur in abnormal phis. */
if ((TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME
/* Do not un-cse comparisons. But propagate through copies. */
use_stmt = get_prop_dest_stmt (name, &name);
- if (!use_stmt)
+ if (!use_stmt
+ || !is_gimple_assign (use_stmt))
return false;
- /* Conversion of the condition result to another integral type. */
- if (is_gimple_assign (use_stmt)
- && (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (use_stmt))
- || TREE_CODE_CLASS (gimple_assign_rhs_code (use_stmt))
- == tcc_comparison
- || gimple_assign_rhs_code (use_stmt) == TRUTH_NOT_EXPR)
- && INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (use_stmt))))
- {
- tree lhs = gimple_assign_lhs (use_stmt);
-
- /* We can propagate the condition into a conversion. */
- if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (use_stmt)))
- {
- /* Avoid using fold here as that may create a COND_EXPR with
- non-boolean condition as canonical form. */
- tmp = build2 (gimple_assign_rhs_code (stmt), TREE_TYPE (lhs),
- gimple_assign_rhs1 (stmt), gimple_assign_rhs2 (stmt));
- }
- /* We can propagate the condition into X op CST where op
- is EQ_EXPR or NE_EXPR and CST is either one or zero. */
- else if (TREE_CODE_CLASS (gimple_assign_rhs_code (use_stmt))
- == tcc_comparison
- && TREE_CODE (gimple_assign_rhs1 (use_stmt)) == SSA_NAME
- && TREE_CODE (gimple_assign_rhs2 (use_stmt)) == INTEGER_CST)
- {
- enum tree_code code = gimple_assign_rhs_code (use_stmt);
- tree cst = gimple_assign_rhs2 (use_stmt);
- tree cond;
-
- cond = build2 (gimple_assign_rhs_code (stmt),
- TREE_TYPE (cst),
- gimple_assign_rhs1 (stmt),
- gimple_assign_rhs2 (stmt));
-
- tmp = combine_cond_expr_cond (gimple_location (use_stmt),
- code, TREE_TYPE (lhs),
- cond, cst, false);
- if (tmp == NULL_TREE)
- return false;
- }
- /* We can propagate the condition into a statement that
- computes the logical negation of the comparison result. */
- else if (gimple_assign_rhs_code (use_stmt) == TRUTH_NOT_EXPR)
- {
- tree type = TREE_TYPE (gimple_assign_rhs1 (stmt));
- bool nans = HONOR_NANS (TYPE_MODE (type));
- enum tree_code code;
- code = invert_tree_comparison (gimple_assign_rhs_code (stmt), nans);
- if (code == ERROR_MARK)
- return false;
+ code = gimple_assign_rhs_code (use_stmt);
+ lhs = gimple_assign_lhs (use_stmt);
+ if (!INTEGRAL_TYPE_P (TREE_TYPE (lhs)))
+ return false;
- tmp = build2 (code, TREE_TYPE (lhs), gimple_assign_rhs1 (stmt),
- gimple_assign_rhs2 (stmt));
- }
- else
+ /* We can propagate the condition into a statement that
+ computes the logical negation of the comparison result. */
+ if ((code == BIT_NOT_EXPR
+ && TYPE_PRECISION (TREE_TYPE (lhs)) == 1)
+ || (code == BIT_XOR_EXPR
+ && integer_onep (gimple_assign_rhs2 (use_stmt))))
+ {
+ tree type = TREE_TYPE (gimple_assign_rhs1 (stmt));
+ bool nans = HONOR_NANS (TYPE_MODE (type));
+ enum tree_code inv_code;
+ inv_code = invert_tree_comparison (gimple_assign_rhs_code (stmt), nans);
+ if (inv_code == ERROR_MARK)
return false;
- {
- gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt);
- gimple_assign_set_rhs_from_tree (&gsi, unshare_expr (tmp));
- use_stmt = gsi_stmt (gsi);
- update_stmt (use_stmt);
- }
-
- /* 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))
- {
- tree old_rhs = rhs_to_tree (TREE_TYPE (gimple_assign_lhs (stmt)),
- stmt);
- fprintf (dump_file, " Replaced '");
- print_generic_expr (dump_file, old_rhs, dump_flags);
- fprintf (dump_file, "' with '");
- print_generic_expr (dump_file, tmp, dump_flags);
- fprintf (dump_file, "'\n");
- }
+ 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.
there's less work to do for each NOT/NEG expression we find.
Backwards propagation needs to look at the statement in a single
backlink. Forward propagation needs to look at potentially more
- than one forward link. */
+ than one forward link.
-static void
+ Returns true when the statement was changed. */
+
+static bool
simplify_not_neg_expr (gimple_stmt_iterator *gsi_p)
{
gimple stmt = gsi_stmt (*gsi_p);
gimple_assign_set_rhs_from_tree (gsi_p, rhs_def_operand);
stmt = gsi_stmt (*gsi_p);
update_stmt (stmt);
+ return true;
}
}
+
+ return false;
}
/* STMT is a SWITCH_EXPR for which we attempt to find equivalent forms of
the condition which we may be able to optimize better. */
-static void
+static bool
simplify_gimple_switch (gimple stmt)
{
tree cond = gimple_switch_index (stmt);
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);
{
gimple_switch_set_index (stmt, def);
update_stmt (stmt);
+ return true;
}
}
}
}
+
+ return false;
}
-/* Run bitwise and assignments throug the folder. If the first argument is an
- ssa name that is itself a result of a typecast of an ADDR_EXPR to an
- integer, feed the ADDR_EXPR to the folder rather than the ssa name.
-*/
+/* For pointers p2 and p1 return p2 - p1 if the
+ difference is known and constant, otherwise return NULL. */
-static void
-simplify_bitwise_and (gimple_stmt_iterator *gsi, gimple stmt)
+static tree
+constant_pointer_difference (tree p1, tree p2)
{
- tree res;
- tree arg1 = gimple_assign_rhs1 (stmt);
- tree arg2 = gimple_assign_rhs2 (stmt);
+ int i, j;
+#define CPD_ITERATIONS 5
+ tree exps[2][CPD_ITERATIONS];
+ tree offs[2][CPD_ITERATIONS];
+ int cnt[2];
- if (TREE_CODE (arg2) != INTEGER_CST)
- return;
-
- if (TREE_CODE (arg1) == SSA_NAME && !SSA_NAME_IS_DEFAULT_DEF (arg1))
+ for (i = 0; i < 2; i++)
{
- gimple def = SSA_NAME_DEF_STMT (arg1);
-
- if (gimple_assign_cast_p (def)
- && INTEGRAL_TYPE_P (gimple_expr_type (def)))
+ 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 op = gimple_assign_rhs1 (def);
-
- if (TREE_CODE (op) == ADDR_EXPR)
- arg1 = op;
+ if (!POINTER_TYPE_P (TREE_TYPE (p)))
+ break;
+ if (TREE_CODE (p) == ADDR_EXPR)
+ {
+ tree q = TREE_OPERAND (p, 0);
+ HOST_WIDE_INT offset;
+ tree base = get_addr_base_and_unit_offset (q, &offset);
+ if (base)
+ {
+ q = base;
+ if (offset)
+ off = size_binop (PLUS_EXPR, off, size_int (offset));
+ }
+ if (TREE_CODE (q) == MEM_REF
+ && TREE_CODE (TREE_OPERAND (q, 0)) == SSA_NAME)
+ {
+ p = TREE_OPERAND (q, 0);
+ off = size_binop (PLUS_EXPR, off,
+ double_int_to_tree (sizetype,
+ mem_ref_offset (q)));
+ }
+ else
+ {
+ exps[i][j] = q;
+ offs[i][j++] = off;
+ break;
+ }
+ }
+ if (TREE_CODE (p) != SSA_NAME)
+ break;
+ exps[i][j] = p;
+ offs[i][j++] = off;
+ if (j == CPD_ITERATIONS)
+ break;
+ stmt = SSA_NAME_DEF_STMT (p);
+ if (!is_gimple_assign (stmt) || gimple_assign_lhs (stmt) != p)
+ break;
+ code = gimple_assign_rhs_code (stmt);
+ if (code == POINTER_PLUS_EXPR)
+ {
+ if (TREE_CODE (gimple_assign_rhs2 (stmt)) != INTEGER_CST)
+ break;
+ off = size_binop (PLUS_EXPR, off, gimple_assign_rhs2 (stmt));
+ p = gimple_assign_rhs1 (stmt);
+ }
+ else if (code == ADDR_EXPR || code == NOP_EXPR)
+ p = gimple_assign_rhs1 (stmt);
+ else
+ break;
}
+ while (1);
+ cnt[i] = j;
}
- res = fold_binary_loc (gimple_location (stmt),
- BIT_AND_EXPR, TREE_TYPE (gimple_assign_lhs (stmt)),
- arg1, arg2);
- if (res && is_gimple_min_invariant (res))
- {
- gimple_assign_set_rhs_from_tree (gsi, res);
- update_stmt (stmt);
- }
- return;
+ 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;
}
-/* Main entry point for the forward propagation optimizer. */
+/* *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 unsigned int
-tree_ssa_forward_propagate_single_use_vars (void)
+static bool
+simplify_builtin_call (gimple_stmt_iterator *gsi_p, tree callee2)
{
- basic_block bb;
- unsigned int todoflags = 0;
-
- cfg_changed = false;
+ gimple stmt1, stmt2 = gsi_stmt (*gsi_p);
+ tree vuse = gimple_vuse (stmt2);
+ if (vuse == NULL)
+ return false;
+ stmt1 = SSA_NAME_DEF_STMT (vuse);
- FOR_EACH_BB (bb)
+ switch (DECL_FUNCTION_CODE (callee2))
{
- gimple_stmt_iterator gsi;
-
- /* Note we update GSI within the loop as necessary. */
- for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); )
+ case BUILT_IN_MEMSET:
+ if (gimple_call_num_args (stmt2) != 3
+ || gimple_call_lhs (stmt2)
+ || CHAR_BIT != 8
+ || BITS_PER_UNIT != 8)
+ break;
+ else
{
- gimple stmt = gsi_stmt (gsi);
+ 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;
- /* If this statement sets an SSA_NAME to an address,
- try to propagate the address into the uses of the SSA_NAME. */
- if (is_gimple_assign (stmt))
+ 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))
{
- tree lhs = gimple_assign_lhs (stmt);
- tree rhs = gimple_assign_rhs1 (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;
+ }
+ }
- if (TREE_CODE (lhs) != SSA_NAME)
+ /* (-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)
{
- gsi_next (&gsi);
- continue;
+ /* (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);
}
-
- if (gimple_assign_rhs_code (stmt) == ADDR_EXPR
- /* Handle pointer conversions on invariant addresses
- as well, as this is valid gimple. */
- || (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt))
- && TREE_CODE (rhs) == ADDR_EXPR
- && POINTER_TYPE_P (TREE_TYPE (lhs))))
+ 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)
{
- STRIP_NOPS (rhs);
- if (!stmt_references_abnormal_ssa_name (stmt)
- && forward_propagate_addr_expr (lhs, rhs))
+ /* (CST +- A) +- CST -> CST +- A. */
+ tree cst = fold_binary (code, TREE_TYPE (rhs1),
+ def_rhs1, rhs2);
+ if (cst && !TREE_OVERFLOW (cst))
{
- release_defs (stmt);
- todoflags |= TODO_remove_unused_locals;
- gsi_remove (&gsi, true);
+ 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
- gsi_next (&gsi);
}
- else if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR
- && is_gimple_min_invariant (rhs))
+ else if (TREE_CODE (rhs2) == INTEGER_CST
+ && TREE_CODE (def_rhs2) == INTEGER_CST
+ && def_code == PLUS_EXPR)
{
- /* Make sure to fold &a[0] + off_1 here. */
- fold_stmt_inplace (stmt);
- update_stmt (stmt);
- if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR)
- gsi_next (&gsi);
+ /* (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 ((gimple_assign_rhs_code (stmt) == BIT_NOT_EXPR
- || gimple_assign_rhs_code (stmt) == NEGATE_EXPR)
- && TREE_CODE (rhs) == SSA_NAME)
+ }
+ 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))
{
- simplify_not_neg_expr (&gsi);
- gsi_next (&gsi);
+ /* ~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 (gimple_assign_rhs_code (stmt) == COND_EXPR)
- {
- /* In this case the entire COND_EXPR is in rhs1. */
- int did_something;
- fold_defer_overflow_warnings ();
- did_something = forward_propagate_into_cond (&gsi);
- stmt = gsi_stmt (gsi);
- if (did_something == 2)
- cfg_changed = true;
- fold_undefer_overflow_warnings (!TREE_NO_WARNING (rhs)
- && did_something, stmt, WARN_STRICT_OVERFLOW_CONDITIONAL);
- gsi_next (&gsi);
- }
- else if (TREE_CODE_CLASS (gimple_assign_rhs_code (stmt))
- == tcc_comparison)
+ else if (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)
{
- if (forward_propagate_comparison (stmt))
+ /* A +- (B +- A) -> +- B. */
+ code = ((code == PLUS_EXPR)
+ ? TREE_CODE (def_rhs1) : NEGATE_EXPR);
+ rhs1 = def_rhs1;
+ rhs2 = NULL_TREE;
+ gimple_assign_set_rhs_with_ops (gsi, code, rhs1, NULL_TREE);
+ gcc_assert (gsi_stmt (*gsi) == stmt);
+ gimple_set_modified (stmt, true);
+ }
+ else if (TREE_CODE (rhs1) == INTEGER_CST
+ && TREE_CODE (def_rhs1) == INTEGER_CST)
+ {
+ /* CST +- (CST +- A) -> CST +- A. */
+ tree cst = fold_binary (code, TREE_TYPE (rhs2),
+ rhs1, def_rhs1);
+ if (cst && !TREE_OVERFLOW (cst))
{
- release_defs (stmt);
- todoflags |= TODO_remove_unused_locals;
- gsi_remove (&gsi, 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
- gsi_next (&gsi);
}
- else if (gimple_assign_rhs_code (stmt) == BIT_AND_EXPR)
+ else if (TREE_CODE (rhs1) == INTEGER_CST
+ && TREE_CODE (def_rhs2) == INTEGER_CST)
{
- simplify_bitwise_and (&gsi, stmt);
- gsi_next (&gsi);
+ /* 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 (gimple_code (stmt) == GIMPLE_SWITCH)
+ else if (code == POINTER_PLUS_EXPR)
{
- simplify_gimple_switch (stmt);
- gsi_next (&gsi);
+ 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
+ gsi_next (&gsi);
}
- else if (gimple_code (stmt) == GIMPLE_COND)
+ else if (TREE_CODE_CLASS (code) == tcc_comparison)
{
- int did_something;
- fold_defer_overflow_warnings ();
- did_something = forward_propagate_into_gimple_cond (stmt);
- if (did_something == 2)
- cfg_changed = true;
- fold_undefer_overflow_warnings (did_something, stmt,
- WARN_STRICT_OVERFLOW_CONDITIONAL);
+ if (forward_propagate_comparison (stmt))
+ cfg_changed = true;
gsi_next (&gsi);
}
else
gsi_next (&gsi);
}
+
+ /* Combine stmts with the stmts defining their operands.
+ Note we update GSI within the loop as necessary. */
+ prev_initialized = false;
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi);)
+ {
+ gimple stmt = gsi_stmt (gsi);
+ bool changed = false;
+
+ switch (gimple_code (stmt))
+ {
+ case GIMPLE_ASSIGN:
+ {
+ tree rhs1 = gimple_assign_rhs1 (stmt);
+ enum tree_code code = gimple_assign_rhs_code (stmt);
+
+ if ((code == BIT_NOT_EXPR
+ || code == NEGATE_EXPR)
+ && TREE_CODE (rhs1) == SSA_NAME)
+ changed = simplify_not_neg_expr (&gsi);
+ else if (code == COND_EXPR)
+ {
+ /* In this case the entire COND_EXPR is in rhs1. */
+ changed |= forward_propagate_into_cond (&gsi);
+ stmt = gsi_stmt (gsi);
+ }
+ else if (TREE_CODE_CLASS (code) == tcc_comparison)
+ {
+ int did_something;
+ did_something = forward_propagate_into_comparison (&gsi);
+ if (did_something == 2)
+ cfg_changed = true;
+ changed = did_something != 0;
+ }
+ else if (code == BIT_AND_EXPR
+ || code == BIT_IOR_EXPR
+ || code == BIT_XOR_EXPR)
+ changed = simplify_bitwise_binary (&gsi);
+ else if (code == PLUS_EXPR
+ || code == MINUS_EXPR)
+ changed = associate_plusminus (&gsi);
+ else if (CONVERT_EXPR_CODE_P (code)
+ || code == FLOAT_EXPR
+ || code == FIX_TRUNC_EXPR)
+ {
+ int did_something = combine_conversions (&gsi);
+ if (did_something == 2)
+ cfg_changed = true;
+ changed = did_something != 0;
+ }
+ break;
+ }
+
+ case GIMPLE_SWITCH:
+ changed = simplify_gimple_switch (stmt);
+ break;
+
+ case GIMPLE_COND:
+ {
+ int did_something;
+ did_something = forward_propagate_into_gimple_cond (stmt);
+ if (did_something == 2)
+ cfg_changed = true;
+ changed = did_something != 0;
+ break;
+ }
+
+ case GIMPLE_CALL:
+ {
+ tree callee = gimple_call_fndecl (stmt);
+ if (callee != NULL_TREE
+ && DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL)
+ changed = simplify_builtin_call (&gsi, callee);
+ break;
+ }
+
+ default:;
+ }
+
+ if (changed)
+ {
+ /* 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
+ {
+ prev = gsi;
+ prev_initialized = true;
+ gsi_next (&gsi);
+ }
+ }
}
if (cfg_changed)
todoflags |= TODO_cleanup_cfg;
+
return todoflags;
}
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 */
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 */
}
};
-
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