/* Forward propagation of expressions for single use variables.
- Copyright (C) 2004, 2005, 2007 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
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;
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:
if (a EQ/NEQ (c2 - c1)) goto ... else goto ...
Similarly for x = a - c1.
-
+
Or
bb0:
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<type1>(type2var)
+
+ Or
ptr = &x[0];
ptr2 = ptr + <constant>;
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}.
/* 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
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)
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;
+
if (!single_use_only && single_use_p)
*single_use_p = single_use;
- return def_stmt;
+ /* We can look through pointer conversions in the search
+ for a useful stmt for the comparison folding. */
+ 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_assign_rhs1 (def_stmt);
}
-
- /* Continue searching the def of the copy source name. */
- name = GIMPLE_STMT_OPERAND (def_stmt, 1);
} while (1);
}
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;
- /* 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;
+ /* Constants can be always propagated. */
+ if (gimple_assign_single_p (def_stmt)
+ && is_gimple_min_invariant (gimple_assign_rhs1 (def_stmt)))
+ return true;
- default:
- return false;
- }
+ /* We cannot propagate ssa names that occur in abnormal phi nodes. */
+ 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
considered simplified. */
static tree
-combine_cond_expr_cond (enum tree_code code, tree type,
+combine_cond_expr_cond (location_t loc, 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);
+ t = fold_binary_loc (loc, code, type, op0, op1);
if (!t)
return NULL_TREE;
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)))
+ if (!t || (invariant_only && !is_gimple_min_invariant (t)))
return NULL_TREE;
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 (location_t loc,
+ 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 (loc, 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 (loc, 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 (loc, 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 rhs1 = gimple_assign_rhs1 (stmt);
+ tree rhs2 = gimple_assign_rhs2 (stmt);
+
+ /* Combine the comparison with defining statements. */
+ tmp = forward_propagate_into_comparison_1 (gimple_location (stmt),
+ gimple_assign_rhs_code (stmt),
+ TREE_TYPE
+ (gimple_assign_lhs (stmt)),
+ rhs1, rhs2);
+ if (tmp)
+ {
+ gimple_assign_set_rhs_from_tree (gsi, tmp);
+ update_stmt (stmt);
+ 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;
+ location_t loc = gimple_location (stmt);
+ 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 (loc, 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);
+ return 0;
+}
- /* Remove defining statements. */
- remove_prop_source_from_use (name, NULL);
- if (is_gimple_min_invariant (tmp))
- did_something = 2;
- else if (did_something == 0)
- did_something = 1;
+/* 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.
- /* Continue combining. */
- continue;
- }
+ This must be kept in sync with forward_propagate_into_gimple_cond. */
- break;
- } while (1);
+static int
+forward_propagate_into_cond (gimple_stmt_iterator *gsi_p)
+{
+ gimple stmt = gsi_stmt (*gsi_p);
+ location_t loc = gimple_location (stmt);
+ tree tmp = NULL_TREE;
+ tree cond = gimple_assign_rhs1 (stmt);
+
+ /* We can do tree combining on SSA_NAME and comparison expressions. */
+ if (COMPARISON_CLASS_P (cond))
+ tmp = forward_propagate_into_comparison_1 (loc, TREE_CODE (cond),
+ boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1));
+ else if (TREE_CODE (cond) == SSA_NAME)
+ {
+ tree name = cond, rhs0;
+ gimple def_stmt = get_prop_source_stmt (name, true, NULL);
+ if (!def_stmt || !can_propagate_from (def_stmt))
+ return 0;
+
+ 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);
+ }
- return did_something;
+ 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);
+
+ return is_gimple_min_invariant (tmp) ? 2 : 1;
+ }
+
+ 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.
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;
+ 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);
+ use_stmt = gsi_stmt (*use_stmt_gsi);
/* That should have created gimple, so there is no need to
record information to undo the propagation. */
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;
-
- /* Strip away any outer COMPONENT_REF/ARRAY_REF nodes from the LHS.
- ADDR_EXPR will not appear on the LHS. */
- lhs = GIMPLE_STMT_OPERAND (use_stmt, 0);
- while (handled_component_p (lhs))
- lhs = TREE_OPERAND (lhs, 0);
+ tree lhs, rhs, rhs2, array_ref;
+ gimple use_stmt = gsi_stmt (*use_stmt_gsi);
+ enum tree_code rhs_code;
+ bool res = true;
- rhs = GIMPLE_STMT_OPERAND (use_stmt, 1);
-
- /* Now see if the LHS node is an INDIRECT_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 should always succeed in creating gimple, so there is
- no need to save enough state to undo this propagation. */
- TREE_OPERAND (lhs, 0) = unshare_expr (def_rhs);
- fold_stmt_inplace (use_stmt);
- tidy_after_forward_propagate_addr (use_stmt);
+ gcc_assert (TREE_CODE (def_rhs) == ADDR_EXPR);
- /* Continue propagating into the RHS. */
- }
+ 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
- not copy through differen variant pointers and FRE does not catch
+ not copy through different variant pointers and FRE does not catch
all useless conversions. Treat the case of a single-use name and
a conversion to def_rhs type separate, though. */
- else if (TREE_CODE (lhs) == SSA_NAME
- && (TREE_CODE (rhs) == NOP_EXPR
- || TREE_CODE (rhs) == CONVERT_EXPR)
- && TREE_TYPE (rhs) == TREE_TYPE (def_rhs)
- && single_use_p)
+ if (TREE_CODE (lhs) == SSA_NAME
+ && ((rhs_code == SSA_NAME && rhs == name)
+ || CONVERT_EXPR_CODE_P (rhs_code)))
+ {
+ /* 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_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)
{
- GIMPLE_STMT_OPERAND (use_stmt, 1) = unshare_expr (def_rhs);
+ 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;
}
- else 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))))
- return forward_propagate_addr_expr (lhs, def_rhs);
+
+ /* Now strip away any outer COMPONENT_REF/ARRAY_REF nodes from the LHS.
+ ADDR_EXPR will not appear on the LHS. */
+ lhs = gimple_assign_lhs (use_stmt);
+ while (handled_component_p (lhs))
+ lhs = TREE_OPERAND (lhs, 0);
+
+ /* 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) == MEM_REF
+ && TREE_OPERAND (lhs, 0) == name)
+ {
+ 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
+ && 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;
+ while (handled_component_p (*def_rhs_basep))
+ def_rhs_basep = &TREE_OPERAND (*def_rhs_basep, 0);
+ saved = *def_rhs_basep;
+ if (TREE_CODE (*def_rhs_basep) == MEM_REF)
+ {
+ new_base = TREE_OPERAND (*def_rhs_basep, 0);
+ new_offset
+ = int_const_binop (PLUS_EXPR, TREE_OPERAND (lhs, 1),
+ TREE_OPERAND (*def_rhs_basep, 1));
+ }
+ 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_THIS_NOTRAP (*def_rhs_basep) = TREE_THIS_NOTRAP (lhs);
+ gimple_assign_set_lhs (use_stmt,
+ unshare_expr (TREE_OPERAND (def_rhs, 0)));
+ *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. */
- while (handled_component_p (rhs)
- || TREE_CODE (rhs) == ADDR_EXPR)
+ 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)
+ if (TREE_CODE (rhs) == MEM_REF
+ && TREE_OPERAND (rhs, 0) == name)
{
- /* This should always succeed in creating gimple, so there is
- no need to save enough state to undo this propagation. */
- TREE_OPERAND (rhs, 0) = unshare_expr (def_rhs);
- 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);
+ 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
+ && 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;
+ while (handled_component_p (*def_rhs_basep))
+ def_rhs_basep = &TREE_OPERAND (*def_rhs_basep, 0);
+ saved = *def_rhs_basep;
+ if (TREE_CODE (*def_rhs_basep) == MEM_REF)
+ {
+ new_base = TREE_OPERAND (*def_rhs_basep, 0);
+ new_offset
+ = int_const_binop (PLUS_EXPR, TREE_OPERAND (rhs, 1),
+ TREE_OPERAND (*def_rhs_basep, 1));
+ }
+ 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_THIS_NOTRAP (*def_rhs_basep) = TREE_THIS_NOTRAP (rhs);
+ gimple_assign_set_rhs1 (use_stmt,
+ unshare_expr (TREE_OPERAND (def_rhs, 0)));
+ *def_rhs_basep = saved;
+ 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
+ || gimple_assign_rhs1 (use_stmt) != name)
+ return false;
+
/* The remaining cases are all for turning pointer arithmetic into
array indexing. They only apply when we have the address of
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)))
- return false;
-
- /* 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)
+ 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_OPERAND (rhs, 0) == name
- && TREE_CODE (TREE_OPERAND (rhs, 1)) == INTEGER_CST)
+ 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]. */
+ 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))
+ 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;
}
- else
- {
- GIMPLE_STMT_OPERAND (use_stmt, 1) = orig;
- update_stmt (use_stmt);
- return false;
- }
}
/* 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_OPERAND (rhs, 0) == name
- && 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;
}
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);
FOR_EACH_IMM_USE_STMT (use_stmt, iter, name)
{
bool result;
+ tree use_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_assign_rhs1 (use_stmt);
if (result
- && TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 0)) == SSA_NAME
- && (TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 1)) == SSA_NAME
- || TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 1)) == NOP_EXPR
- || TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 1)) == CONVERT_EXPR))
+ && 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
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.
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);
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;
-
- cfg_changed = false;
+ int i, j;
+#define CPD_ITERATIONS 5
+ tree exps[2][CPD_ITERATIONS];
+ tree offs[2][CPD_ITERATIONS];
+ int cnt[2];
- 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
- /* We can also disregard changes in CV qualifiers for
- the dereferenced value. */
- || ((TREE_CODE (rhs) == NOP_EXPR
- || TREE_CODE (rhs) == CONVERT_EXPR)
- && TREE_CODE (TREE_OPERAND (rhs, 0)) == ADDR_EXPR
- && POINTER_TYPE_P (TREE_TYPE (rhs))
- && types_compatible_p (TREE_TYPE (TREE_TYPE (TREE_OPERAND (rhs, 0))),
- TREE_TYPE (TREE_TYPE (rhs)))))
+ if (TREE_CODE (q) == MEM_REF
+ && TREE_CODE (TREE_OPERAND (q, 0)) == SSA_NAME)
{
- if (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
{
- simplify_not_neg_expr (stmt);
- bsi_next (&bsi);
+ exps[i][j] = q;
+ offs[i][j++] = off;
+ break;
}
- 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))
- {
- if (forward_propagate_comparison (rhs, stmt))
- {
- release_defs (stmt);
- todoflags |= TODO_remove_unused_locals;
- bsi_remove (&bsi, true);
- }
- else
- bsi_next (&bsi);
- }
- else
- bsi_next (&bsi);
}
- else if (TREE_CODE (stmt) == SWITCH_EXPR)
+ 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)
{
- simplify_switch_expr (stmt);
- bsi_next (&bsi);
- }
- else if (TREE_CODE (stmt) == COND_EXPR)
- {
- 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);
+ 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
- bsi_next (&bsi);
+ break;
}
+ while (1);
+ cnt[i] = j;
}
- if (cfg_changed)
- todoflags |= TODO_cleanup_cfg;
- return todoflags;
+ 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
-gate_forwprop (void)
+simplify_builtin_call (gimple_stmt_iterator *gsi_p, tree callee2)
{
- return 1;
-}
-
-struct tree_opt_pass pass_forwprop = {
- "forwprop", /* name */
- gate_forwprop, /* gate */
- tree_ssa_forward_propagate_single_use_vars, /* execute */
- NULL, /* sub */
- NULL, /* next */
- 0, /* static_pass_number */
- TV_TREE_FORWPROP, /* tv_id */
- PROP_cfg | PROP_ssa, /* properties_required */
- 0, /* properties_provided */
- 0, /* properties_destroyed */
- 0, /* todo_flags_start */
- TODO_dump_func
- | TODO_ggc_collect
- | TODO_update_ssa
- | TODO_verify_ssa, /* todo_flags_finish */
- 0 /* letter */
-};
+ 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;
-/* Structure to keep track of the value of a dereferenced PHI result
- and the set of virtual operands used for that dereference. */
+ 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, BIGGEST_ALIGNMENT);
+ /* 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, built_in_decls [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;
+}
-struct phiprop_d
+/* Checks if expression has type of one-bit precision, or is a known
+ truth-valued expression. */
+static bool
+truth_valued_ssa_name (tree name)
{
- tree value;
- tree vop_stmt;
-};
+ gimple def;
+ tree type = TREE_TYPE (name);
-/* Verify if the value recorded for NAME in PHIVN is still valid at
- the start of basic block BB. */
+ 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;
+}
-static bool
-phivn_valid_p (struct phiprop_d *phivn, tree name, basic_block bb)
+/* 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 vop_stmt = phivn[SSA_NAME_VERSION (name)].vop_stmt;
- ssa_op_iter ui;
- tree vuse;
+ 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;
- /* The def stmts of all virtual uses need to be post-dominated
- by bb. */
- FOR_EACH_SSA_TREE_OPERAND (vuse, vop_stmt, ui, SSA_OP_VUSE)
- {
- tree use_stmt;
- imm_use_iterator ui2;
- bool ok = true;
+ code = gimple_assign_rhs_code (def);
+ op1 = gimple_assign_rhs1 (def);
+ op2 = NULL_TREE;
- FOR_EACH_IMM_USE_STMT (use_stmt, ui2, vuse)
- {
- /* If BB does not dominate a VDEF, the value is invalid. */
- if (((TREE_CODE (use_stmt) == GIMPLE_MODIFY_STMT
- && !ZERO_SSA_OPERANDS (use_stmt, SSA_OP_VDEF))
- || TREE_CODE (use_stmt) == PHI_NODE)
- && !dominated_by_p (CDI_DOMINATORS, bb_for_stmt (use_stmt), bb))
- {
- ok = false;
- BREAK_FROM_IMM_USE_STMT (ui2);
- }
- }
- if (!ok)
- return false;
+ /* 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 true;
+ return NULL_TREE;
}
-/* Insert a new phi node for the dereference of PHI at basic_block
- BB with the virtual operands from USE_STMT. */
-
+/* 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
-phiprop_insert_phi (basic_block bb, tree phi, tree use_stmt,
- struct phiprop_d *phivn, size_t n)
+simplify_bitwise_binary_1 (enum tree_code code, tree type,
+ tree arg1, tree arg2)
{
- tree res, new_phi;
- edge_iterator ei;
- edge e;
-
- /* Build a new PHI node to replace the definition of
- the indirect reference lhs. */
- res = GIMPLE_STMT_OPERAND (use_stmt, 0);
- SSA_NAME_DEF_STMT (res) = new_phi = create_phi_node (res, bb);
-
- /* Add PHI arguments for each edge inserting loads of the
- addressable operands. */
- FOR_EACH_EDGE (e, ei, bb->preds)
+ 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)
{
- tree old_arg, new_var, tmp;
+ def1 = SSA_NAME_DEF_STMT (arg1);
+ if (is_gimple_assign (def1))
+ {
+ def1_code = gimple_assign_rhs_code (def1);
+ def1_arg1 = gimple_assign_rhs1 (def1);
+ }
+ }
- old_arg = PHI_ARG_DEF_FROM_EDGE (phi, e);
- while (TREE_CODE (old_arg) == SSA_NAME
- && (SSA_NAME_VERSION (old_arg) >= n
- || phivn[SSA_NAME_VERSION (old_arg)].value == NULL_TREE))
+ def2_code = TREE_CODE (arg2);
+ def2_arg1 = arg2;
+ if (TREE_CODE (arg2) == SSA_NAME)
+ {
+ def2 = SSA_NAME_DEF_STMT (arg2);
+ if (is_gimple_assign (def2))
{
- tree def_stmt = SSA_NAME_DEF_STMT (old_arg);
- old_arg = GIMPLE_STMT_OPERAND (def_stmt, 1);
+ def2_code = gimple_assign_rhs_code (def2);
+ def2_arg1 = gimple_assign_rhs1 (def2);
}
+ }
- if (TREE_CODE (old_arg) == SSA_NAME)
- /* Reuse a formerly created dereference. */
- new_var = phivn[SSA_NAME_VERSION (old_arg)].value;
- else
+ /* 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))
{
- old_arg = TREE_OPERAND (old_arg, 0);
- new_var = create_tmp_var (TREE_TYPE (old_arg), NULL);
- tmp = build2 (GIMPLE_MODIFY_STMT, void_type_node,
- NULL_TREE, unshare_expr (old_arg));
- if (TREE_CODE (TREE_TYPE (old_arg)) == COMPLEX_TYPE
- || TREE_CODE (TREE_TYPE (old_arg)) == VECTOR_TYPE)
- DECL_GIMPLE_REG_P (new_var) = 1;
- add_referenced_var (new_var);
- new_var = make_ssa_name (new_var, tmp);
- GIMPLE_STMT_OPERAND (tmp, 0) = new_var;
-
- bsi_insert_on_edge (e, tmp);
-
- update_stmt (tmp);
- mark_symbols_for_renaming (tmp);
+ 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;
+ }
- add_phi_arg (new_phi, new_var, e);
+ /* 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;
}
- update_stmt (new_phi);
+ /* 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;
+ }
- return res;
+ /* 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;
}
-/* Propagate between the phi node arguments of PHI in BB and phi result
- users. For now this matches
- # p_2 = PHI <&x, &y>
- <Lx>:;
- p_3 = p_2;
- z_2 = *p_3;
- and converts it to
- # z_2 = PHI <x, y>
- <Lx>:;
- Returns true if a transformation was done and edge insertions
- need to be committed. Global data PHIVN and N is used to track
- past transformation results. We need to be especially careful here
- with aliasing issues as we are moving memory reads. */
+
+/* Perform re-associations of the plus or minus statement STMT that are
+ always permitted. Returns true if the CFG was changed. */
static bool
-propagate_with_phi (basic_block bb, tree phi, struct phiprop_d *phivn, size_t n)
+associate_plusminus (gimple stmt)
{
- tree ptr = PHI_RESULT (phi);
- tree use_stmt, res = NULL_TREE;
- block_stmt_iterator bsi;
- imm_use_iterator ui;
- use_operand_p arg_p, use;
- ssa_op_iter i;
- bool phi_inserted;
-
- if (MTAG_P (SSA_NAME_VAR (ptr))
- || !POINTER_TYPE_P (TREE_TYPE (ptr))
- || !is_gimple_reg_type (TREE_TYPE (TREE_TYPE (ptr))))
+ tree rhs1 = gimple_assign_rhs1 (stmt);
+ tree rhs2 = gimple_assign_rhs2 (stmt);
+ enum tree_code code = gimple_assign_rhs_code (stmt);
+ gimple_stmt_iterator gsi;
+ bool changed;
+
+ /* We can't reassociate at all for saturating types. */
+ if (TYPE_SATURATING (TREE_TYPE (rhs1)))
return false;
- /* Check if we can "cheaply" dereference all phi arguments. */
- FOR_EACH_PHI_ARG (arg_p, phi, i, SSA_OP_USE)
+ /* First contract negates. */
+ do
{
- tree arg = USE_FROM_PTR (arg_p);
- /* Walk the ssa chain until we reach a ssa name we already
- created a value for or we reach a definition of the form
- ssa_name_n = &var; */
- while (TREE_CODE (arg) == SSA_NAME
- && !SSA_NAME_IS_DEFAULT_DEF (arg)
- && (SSA_NAME_VERSION (arg) >= n
- || phivn[SSA_NAME_VERSION (arg)].value == NULL_TREE))
+ changed = false;
+
+ /* A +- (-B) -> A -+ B. */
+ if (TREE_CODE (rhs2) == SSA_NAME)
{
- tree def_stmt = SSA_NAME_DEF_STMT (arg);
- if (TREE_CODE (def_stmt) != GIMPLE_MODIFY_STMT)
- return false;
- arg = GIMPLE_STMT_OPERAND (def_stmt, 1);
+ 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;
+ }
}
- if ((TREE_CODE (arg) != ADDR_EXPR
- /* Avoid to have to decay *&a to a[0] later. */
- || !is_gimple_reg_type (TREE_TYPE (TREE_OPERAND (arg, 0))))
- && !(TREE_CODE (arg) == SSA_NAME
- && phivn[SSA_NAME_VERSION (arg)].value != NULL_TREE
- && phivn_valid_p (phivn, arg, bb)))
- return false;
- }
- /* Find a dereferencing use. First follow (single use) ssa
- copy chains for ptr. */
- while (single_imm_use (ptr, &use, &use_stmt)
- && TREE_CODE (use_stmt) == GIMPLE_MODIFY_STMT
- && GIMPLE_STMT_OPERAND (use_stmt, 1) == ptr
- && TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 0)) == SSA_NAME)
- ptr = GIMPLE_STMT_OPERAND (use_stmt, 0);
-
- /* Replace the first dereference of *ptr if there is one and if we
- can move the loads to the place of the ptr phi node. */
- phi_inserted = false;
- FOR_EACH_IMM_USE_STMT (use_stmt, ui, ptr)
+ /* (-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. */
+
+ gsi = gsi_for_stmt (stmt);
+ if (TREE_CODE (rhs1) == SSA_NAME)
{
- ssa_op_iter ui2;
- tree vuse;
-
- /* Check whether this is a load of *ptr. */
- if (!(TREE_CODE (use_stmt) == GIMPLE_MODIFY_STMT
- && TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 0)) == SSA_NAME
- && TREE_CODE (GIMPLE_STMT_OPERAND (use_stmt, 1)) == INDIRECT_REF
- && TREE_OPERAND (GIMPLE_STMT_OPERAND (use_stmt, 1), 0) == ptr
- /* We cannot replace a load that may throw or is volatile. */
- && !tree_can_throw_internal (use_stmt)))
- continue;
-
- /* Check if we can move the loads. The def stmts of all virtual uses
- need to be post-dominated by bb. */
- FOR_EACH_SSA_TREE_OPERAND (vuse, use_stmt, ui2, SSA_OP_VUSE)
+ gimple def_stmt = SSA_NAME_DEF_STMT (rhs1);
+ if (is_gimple_assign (def_stmt) && can_propagate_from (def_stmt))
{
- tree def_stmt = SSA_NAME_DEF_STMT (vuse);
- if (!SSA_NAME_IS_DEFAULT_DEF (vuse)
- && (bb_for_stmt (def_stmt) == bb
- || !dominated_by_p (CDI_DOMINATORS,
- bb, bb_for_stmt (def_stmt))))
- goto next;
+ 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);
+ }
+ }
}
+ }
- /* Found a proper dereference. Insert a phi node if this
- is the first load transformation. */
- if (!phi_inserted)
+ 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))
{
- res = phiprop_insert_phi (bb, phi, use_stmt, phivn, n);
+ enum tree_code def_code = gimple_assign_rhs_code (def_stmt);
+ if (def_code == PLUS_EXPR
+ || def_code == MINUS_EXPR)
+ {
+ tree def_rhs1 = gimple_assign_rhs1 (def_stmt);
+ tree def_rhs2 = gimple_assign_rhs2 (def_stmt);
+ if (operand_equal_p (def_rhs1, rhs1, 0)
+ && code == MINUS_EXPR)
+ {
+ /* A - (A +- B) -> -+ B. */
+ code = ((def_code == PLUS_EXPR)
+ ? NEGATE_EXPR : TREE_CODE (def_rhs2));
+ rhs1 = def_rhs2;
+ rhs2 = NULL_TREE;
+ gimple_assign_set_rhs_with_ops (&gsi, code, rhs1, NULL_TREE);
+ gcc_assert (gsi_stmt (gsi) == stmt);
+ gimple_set_modified (stmt, true);
+ }
+ else if (operand_equal_p (def_rhs2, rhs1, 0)
+ && code != def_code)
+ {
+ /* A +- (B +- A) -> +- B. */
+ code = ((code == PLUS_EXPR)
+ ? TREE_CODE (def_rhs1) : NEGATE_EXPR);
+ rhs1 = def_rhs1;
+ rhs2 = NULL_TREE;
+ gimple_assign_set_rhs_with_ops (&gsi, code, rhs1, NULL_TREE);
+ gcc_assert (gsi_stmt (gsi) == stmt);
+ gimple_set_modified (stmt, true);
+ }
+ else if (TREE_CODE (rhs1) == INTEGER_CST
+ && TREE_CODE (def_rhs1) == INTEGER_CST)
+ {
+ /* CST +- (CST +- A) -> CST +- A. */
+ tree cst = fold_binary (code, TREE_TYPE (rhs2),
+ rhs1, def_rhs1);
+ if (cst && !TREE_OVERFLOW (cst))
+ {
+ code = (code == def_code ? PLUS_EXPR : MINUS_EXPR);
+ gimple_assign_set_rhs_code (stmt, code);
+ rhs1 = cst;
+ gimple_assign_set_rhs1 (stmt, rhs1);
+ rhs2 = def_rhs2;
+ gimple_assign_set_rhs2 (stmt, rhs2);
+ gimple_set_modified (stmt, true);
+ }
+ }
+ else if (TREE_CODE (rhs1) == INTEGER_CST
+ && TREE_CODE (def_rhs2) == INTEGER_CST)
+ {
+ /* CST +- (A +- CST) -> CST +- A. */
+ tree cst = fold_binary (def_code == code
+ ? PLUS_EXPR : MINUS_EXPR,
+ TREE_TYPE (rhs2),
+ rhs1, def_rhs2);
+ if (cst && !TREE_OVERFLOW (cst))
+ {
+ rhs1 = cst;
+ gimple_assign_set_rhs1 (stmt, rhs1);
+ rhs2 = def_rhs1;
+ gimple_assign_set_rhs2 (stmt, rhs2);
+ gimple_set_modified (stmt, true);
+ }
+ }
+ }
+ else if (def_code == BIT_NOT_EXPR
+ && INTEGRAL_TYPE_P (TREE_TYPE (rhs2)))
+ {
+ tree def_rhs1 = gimple_assign_rhs1 (def_stmt);
+ if (code == PLUS_EXPR
+ && operand_equal_p (def_rhs1, rhs1, 0))
+ {
+ /* A + ~A -> -1. */
+ code = INTEGER_CST;
+ rhs1 = build_int_cst_type (TREE_TYPE (rhs1), -1);
+ rhs2 = NULL_TREE;
+ gimple_assign_set_rhs_with_ops (&gsi, code, rhs1, NULL_TREE);
+ gcc_assert (gsi_stmt (gsi) == stmt);
+ gimple_set_modified (stmt, true);
+ }
+ }
+ }
+ }
- /* Remember the value we created for *ptr. */
- phivn[SSA_NAME_VERSION (ptr)].value = res;
- phivn[SSA_NAME_VERSION (ptr)].vop_stmt = use_stmt;
+out:
+ if (gimple_modified_p (stmt))
+ {
+ fold_stmt_inplace (stmt);
+ update_stmt (stmt);
+ if (maybe_clean_or_replace_eh_stmt (stmt, stmt)
+ && gimple_purge_dead_eh_edges (gimple_bb (stmt)))
+ return true;
+ }
- /* Remove old stmt. The phi is taken care of by DCE, if we
- want to delete it here we also have to delete all intermediate
- copies. */
- bsi = bsi_for_stmt (use_stmt);
- bsi_remove (&bsi, 0);
+ 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;
+ }
- phi_inserted = true;
+ 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);
+
+ /* 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;
}
- else
+
+ /* 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))
{
- /* Further replacements are easy, just make a copy out of the
- load. */
- GIMPLE_STMT_OPERAND (use_stmt, 1) = res;
- update_stmt (use_stmt);
+ 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;
}
-next:;
- /* Continue searching for a proper dereference. */
+ /* 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 phi_inserted;
+ return 0;
}
-/* Helper walking the dominator tree starting from BB and processing
- phi nodes with global data PHIVN and N. */
+/* Main entry point for the forward propagation and statement combine
+ optimizer. */
-static bool
-tree_ssa_phiprop_1 (basic_block bb, struct phiprop_d *phivn, size_t n)
+static unsigned int
+ssa_forward_propagate_and_combine (void)
{
- bool did_something = false;
- basic_block son;
- tree phi;
+ basic_block bb;
+ unsigned int todoflags = 0;
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
- did_something |= propagate_with_phi (bb, phi, phivn, n);
+ cfg_changed = false;
- for (son = first_dom_son (CDI_DOMINATORS, bb);
- son;
- son = next_dom_son (CDI_DOMINATORS, son))
- did_something |= tree_ssa_phiprop_1 (son, phivn, n);
+ FOR_EACH_BB (bb)
+ {
+ gimple_stmt_iterator gsi, prev;
+ bool prev_initialized;
- return did_something;
-}
+ /* 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;
-/* Main entry for phiprop pass. */
+ if (!is_gimple_assign (stmt))
+ {
+ gsi_next (&gsi);
+ continue;
+ }
-static unsigned int
-tree_ssa_phiprop (void)
-{
- struct phiprop_d *phivn;
+ 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;
+ }
- calculate_dominance_info (CDI_DOMINATORS);
+ /* 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 && can_propagate_from (stmt))
+ {
+ if (TREE_CODE (gimple_assign_rhs2 (stmt)) == INTEGER_CST
+ /* ??? Better adjust the interface to that function
+ instead of building new trees here. */
+ && forward_propagate_addr_expr
+ (lhs,
+ build1 (ADDR_EXPR,
+ TREE_TYPE (rhs),
+ fold_build2 (MEM_REF,
+ TREE_TYPE (TREE_TYPE (rhs)),
+ rhs,
+ fold_convert
+ (ptr_type_node,
+ gimple_assign_rhs2 (stmt))))))
+ {
+ release_defs (stmt);
+ todoflags |= TODO_remove_unused_locals;
+ gsi_remove (&gsi, true);
+ }
+ else if (is_gimple_min_invariant (rhs))
+ {
+ /* Make sure to fold &a[0] + off_1 here. */
+ fold_stmt_inplace (stmt);
+ update_stmt (stmt);
+ if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR)
+ gsi_next (&gsi);
+ }
+ else
+ gsi_next (&gsi);
+ }
+ else if (TREE_CODE_CLASS (code) == tcc_comparison)
+ {
+ forward_propagate_comparison (stmt);
+ 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;
- phivn = XCNEWVEC (struct phiprop_d, num_ssa_names);
+ 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. */
+ 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 (rhs1) && did_something, stmt,
+ WARN_STRICT_OVERFLOW_CONDITIONAL);
+ changed = did_something != 0;
+ }
+ else if (TREE_CODE_CLASS (code) == tcc_comparison)
+ {
+ bool no_warning = gimple_no_warning_p (stmt);
+ int did_something;
+ fold_defer_overflow_warnings ();
+ did_something = forward_propagate_into_comparison (&gsi);
+ if (did_something == 2)
+ cfg_changed = true;
+ fold_undefer_overflow_warnings
+ (!no_warning && changed,
+ stmt, WARN_STRICT_OVERFLOW_CONDITIONAL);
+ 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 (stmt);
+ 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;
+ 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);
+ 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 (tree_ssa_phiprop_1 (ENTRY_BLOCK_PTR, phivn, num_ssa_names))
- bsi_commit_edge_inserts ();
+ 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);
+ }
+ }
+ }
- free (phivn);
+ if (cfg_changed)
+ todoflags |= TODO_cleanup_cfg;
- return 0;
+ return todoflags;
}
+
static bool
-gate_phiprop (void)
+gate_forwprop (void)
{
- return 1;
+ return flag_tree_forwprop;
}
-struct tree_opt_pass pass_phiprop = {
- "phiprop", /* name */
- gate_phiprop, /* gate */
- tree_ssa_phiprop, /* execute */
+struct gimple_opt_pass pass_forwprop =
+{
+ {
+ GIMPLE_PASS,
+ "forwprop", /* name */
+ gate_forwprop, /* gate */
+ 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 */
- 0 /* letter */
+ | TODO_verify_ssa /* todo_flags_finish */
+ }
};
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