-/* Copyright (C) 1998 - 2000 by Universitaet Karlsruhe
-** All rights reserved.
-**
-** Authors: Christian Schaefer, Goetz Lindenmaier
-**
-** iropt --- optimizations intertwined with IR construction.
-*/
+/*
+ * Project: libFIRM
+ * File name: ir/ir/iropt.c
+ * Purpose: iropt --- optimizations intertwined with IR construction.
+ * Author: Christian Schaefer
+ * Modified by: Goetz Lindenmaier
+ * Created:
+ * CVS-ID: $Id$
+ * Copyright: (c) 1998-2003 Universität Karlsruhe
+ * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
+ */
#ifdef HAVE_CONFIG_H
# include <config.h>
# include "irnode_t.h"
# include "irgraph_t.h"
+# include "irmode_t.h"
# include "iropt_t.h"
-# include "ircons.h"
+# include "ircons_t.h"
# include "irgmod.h"
# include "irvrfy.h"
-# include "tv.h"
-# include "tune.h"
-# include "debinfo.h"
+# include "tv_t.h"
+# include "dbginfo_t.h"
+# include "iropt_dbg.h"
+# include "irflag_t.h"
+# include "firmstat.h"
+# include "irarch.h"
/* Make types visible to allow most efficient access */
# include "entity_t.h"
-/* Trivial inlineable routine for copy propagation.
- Does follow Ids, needed to optimize inlined code. */
-static inline ir_node *
+/**
+ * Trivial INLINEable routine for copy propagation.
+ * Does follow Ids, needed to optimize INLINEd code.
+ */
+static INLINE ir_node *
follow_Id (ir_node *n)
{
while (get_irn_op (n) == op_Id) n = get_Id_pred (n);
return n;
}
-static inline tarval *
-value_of (ir_node *n)
+/**
+ * return the value of a Constant
+ */
+static tarval *computed_value_Const(ir_node *n)
{
- if ((n != NULL) && (get_irn_op(n) == op_Const))
return get_Const_tarval(n);
- else
- return NULL;
}
-/* if n can be computed, return the value, else NULL. Performs
- constant folding. GL: Only if n is arithmetic operator? */
-tarval *
-computed_value (ir_node *n)
+/**
+ * return the value of a 'sizeof' SymConst
+ */
+static tarval *computed_value_SymConst(ir_node *n)
{
- tarval *res;
+ if ((get_SymConst_kind(n) == symconst_size) &&
+ (get_type_state(get_SymConst_type(n))) == layout_fixed)
+ return new_tarval_from_long(get_type_size_bytes(get_SymConst_type(n)), get_irn_mode(n));
+ return tarval_bad;
+}
+
+/**
+ * return the value of an Add
+ */
+static tarval *computed_value_Add(ir_node *n)
+{
+ ir_node *a = get_Add_left(n);
+ ir_node *b = get_Add_right(n);
+
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ if ((ta != tarval_bad) && (tb != tarval_bad)
+ && (get_irn_mode(a) == get_irn_mode(b))
+ && !(get_mode_sort(get_irn_mode(a)) == irms_reference)) {
+ return tarval_add(ta, tb);
+ }
+ return tarval_bad;
+}
+
+/**
+ * return the value of a Sub
+ * Special case: a - a
+ */
+static tarval *computed_value_Sub(ir_node *n)
+{
+ ir_node *a = get_Sub_left(n);
+ ir_node *b = get_Sub_right(n);
+ tarval *ta;
+ tarval *tb;
+
+ /* a - a */
+ if (a == b)
+ return get_tarval_null(get_irn_mode(n));
+
+ ta = value_of(a);
+ tb = value_of(b);
+
+ if ((ta != tarval_bad) && (tb != tarval_bad)
+ && (get_irn_mode(a) == get_irn_mode(b))
+ && !(get_mode_sort(get_irn_mode(a)) == irms_reference)) {
+ return tarval_sub(ta, tb);
+ }
+ return tarval_bad;
+}
+
+/**
+ * return the value of an unary Minus
+ */
+static tarval *computed_value_Minus(ir_node *n)
+{
+ ir_node *a = get_Minus_op(n);
+ tarval *ta = value_of(a);
+
+ if ((ta != tarval_bad) && mode_is_signed(get_irn_mode(a)))
+ return tarval_neg(ta);
+
+ return tarval_bad;
+}
+
+/**
+ * return the value of a Mul
+ */
+static tarval *computed_value_Mul(ir_node *n)
+{
+ ir_node *a = get_Mul_left(n);
+ ir_node *b = get_Mul_right(n);
+
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ if ((ta != tarval_bad) && (tb != tarval_bad) && (get_irn_mode(a) == get_irn_mode(b))) {
+ return tarval_mul(ta, tb);
+ } else {
+ /* a*0 = 0 or 0*b = 0:
+ calls computed_value recursive and returns the 0 with proper
+ mode. */
+ tarval *v;
+
+ if ( ( ((v = ta) != tarval_bad)
+ && (v == get_mode_null(get_tarval_mode(v))) )
+ || ( ((v = tb) != tarval_bad)
+ && (v == get_mode_null(get_tarval_mode(v))) )) {
+ return v;
+ }
+ }
+ return tarval_bad;
+}
+
+/**
+ * return the value of a floating point Quot
+ */
+static tarval *computed_value_Quot(ir_node *n)
+{
+ ir_node *a = get_Quot_left(n);
+ ir_node *b = get_Quot_right(n);
+
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ /* This was missing in original implementation. Why? */
+ if ((ta != tarval_bad) && (tb != tarval_bad) && (get_irn_mode(a) == get_irn_mode(b))) {
+ if (tb != get_mode_null(get_tarval_mode(tb))) /* div by zero: return tarval_bad */
+ return tarval_quo(ta, tb);
+ }
+ return tarval_bad;
+}
+
+/**
+ * calculate the value of an integer Div of two nodes
+ * Special case: 0 / b
+ */
+static tarval *do_computed_value_Div(ir_node *a, ir_node *b)
+{
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ /* Compute c1 / c2 or 0 / a, a != 0 */
+ if ((ta != tarval_bad) && (tb != get_mode_null(get_irn_mode(b)))) {
+ if (tb != tarval_bad) /* div by zero: return tarval_bad */
+ return tarval_div(ta, tb);
+ else if (ta == get_mode_null(get_tarval_mode(ta))) /* 0 / b == 0 */
+ return ta;
+ }
+ return tarval_bad;
+}
+
+/**
+ * return the value of an integer Div
+ */
+static tarval *computed_value_Div(ir_node *n)
+{
+ return do_computed_value_Div(get_Div_left(n), get_Div_right(n));
+}
+
+/**
+ * calculate the value of an integer Mod of two nodes
+ * Special case: a % 1
+ */
+static tarval *do_computed_value_Mod(ir_node *a, ir_node *b)
+{
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ /* Compute c1 % c2 or a % 1 */
+ if (tb != tarval_bad) {
+ if ((ta != tarval_bad) && (tb != get_mode_null(get_tarval_mode(tb)))) /* div by zero: return tarval_bad */
+ return tarval_mod(ta, tb);
+ else if (tb == get_mode_one(get_tarval_mode(tb))) /* x mod 1 == 0 */
+ return get_mode_null(get_irn_mode(a));
+ }
+
+ return tarval_bad;
+}
+
+/**
+ * return the value of an integer Mod
+ */
+static tarval *computed_value_Mod(ir_node *n)
+{
+ return do_computed_value_Mod(get_Mod_left(n), get_Mod_right(n));
+}
+
+/**
+ * return the value of an Abs
+ */
+static tarval *computed_value_Abs(ir_node *n)
+{
+ ir_node *a = get_Abs_op(n);
+ tarval *ta = value_of(a);
+
+ if (ta != tarval_bad)
+ return tarval_abs(ta);
+
+ return tarval_bad;
+}
+
+/**
+ * return the value of an And
+ * Special case: a & 0, 0 & b
+ */
+static tarval *computed_value_And(ir_node *n)
+{
+ ir_node *a = get_And_left(n);
+ ir_node *b = get_And_right(n);
+
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ if ((ta != tarval_bad) && (tb != tarval_bad)) {
+ return tarval_and (ta, tb);
+ } else {
+ tarval *v;
+
+ if ( (classify_tarval ((v = computed_value (a))) == TV_CLASSIFY_NULL)
+ || (classify_tarval ((v = computed_value (b))) == TV_CLASSIFY_NULL)) {
+ return v;
+ }
+ }
+ return tarval_bad;
+}
+
+/**
+ * return the value of an Or
+ * Special case: a | 1...1, 1...1 | b
+ */
+static tarval *computed_value_Or(ir_node *n)
+{
+ ir_node *a = get_Or_left(n);
+ ir_node *b = get_Or_right(n);
+
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ if ((ta != tarval_bad) && (tb != tarval_bad)) {
+ return tarval_or (ta, tb);
+ } else {
+ tarval *v;
+ if ( (classify_tarval ((v = computed_value (a))) == TV_CLASSIFY_ALL_ONE)
+ || (classify_tarval ((v = computed_value (b))) == TV_CLASSIFY_ALL_ONE)) {
+ return v;
+ }
+ }
+ return tarval_bad;
+}
+
+/**
+ * return the value of an Eor
+ */
+static tarval *computed_value_Eor(ir_node *n)
+{
+ ir_node *a = get_Eor_left(n);
+ ir_node *b = get_Eor_right(n);
+
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ if ((ta != tarval_bad) && (tb != tarval_bad)) {
+ return tarval_eor (ta, tb);
+ }
+ return tarval_bad;
+}
+
+/**
+ * return the value of a Not
+ */
+static tarval *computed_value_Not(ir_node *n)
+{
+ ir_node *a = get_Not_op(n);
+ tarval *ta = value_of(a);
+
+ if (ta != tarval_bad)
+ return tarval_not(ta);
+
+ return tarval_bad;
+}
+
+/**
+ * return the value of a Shl
+ */
+static tarval *computed_value_Shl(ir_node *n)
+{
+ ir_node *a = get_Shl_left(n);
+ ir_node *b = get_Shl_right(n);
+
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ if ((ta != tarval_bad) && (tb != tarval_bad)) {
+ return tarval_shl (ta, tb);
+ }
+ return tarval_bad;
+}
+
+/**
+ * return the value of a Shr
+ */
+static tarval *computed_value_Shr(ir_node *n)
+{
+ ir_node *a = get_Shr_left(n);
+ ir_node *b = get_Shr_right(n);
+
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ if ((ta != tarval_bad) && (tb != tarval_bad)) {
+ return tarval_shr (ta, tb);
+ }
+ return tarval_bad;
+}
+
+/**
+ * return the value of a Shrs
+ */
+static tarval *computed_value_Shrs(ir_node *n)
+{
+ ir_node *a = get_Shrs_left(n);
+ ir_node *b = get_Shrs_right(n);
+
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ if ((ta != tarval_bad) && (tb != tarval_bad)) {
+ return tarval_shrs (ta, tb);
+ }
+ return tarval_bad;
+}
+
+/**
+ * return the value of a Rot
+ */
+static tarval *computed_value_Rot(ir_node *n)
+{
+ ir_node *a = get_Rot_left(n);
+ ir_node *b = get_Rot_right(n);
+
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ if ((ta != tarval_bad) && (tb != tarval_bad)) {
+ return tarval_rot (ta, tb);
+ }
+ return tarval_bad;
+}
+
+/**
+ * return the value of a Conv
+ */
+static tarval *computed_value_Conv(ir_node *n)
+{
+ ir_node *a = get_Conv_op(n);
+ tarval *ta = value_of(a);
+
+ if (ta != tarval_bad)
+ return tarval_convert_to(ta, get_irn_mode(n));
+
+ return tarval_bad;
+}
+
+/**
+ * return the value of a Proj, handle Proj(Cmp), Proj(Div), Proj(Mod), Proj(DivMod)
+ */
+static tarval *computed_value_Proj(ir_node *n)
+{
+ ir_node *a = get_Proj_pred(n);
+ ir_node *aa, *ab;
+ long proj_nr;
+
+ /* Optimize Cmp nodes.
+ This performs a first step of unreachable code elimination.
+ Proj can not be computed, but folding a Cmp above the Proj here is
+ not as wasteful as folding a Cmp into a Tuple of 16 Consts of which
+ only 1 is used.
+ There are several case where we can evaluate a Cmp node:
+ 1. The nodes compared are both the same. If we compare for
+ equal, greater equal, ... this will return true, else it
+ will return false. This step relies on cse.
+ 2. The predecessors of Cmp are target values. We can evaluate
+ the Cmp.
+ 3. The predecessors are Allocs or void* constants. Allocs never
+ return NULL, they raise an exception. Therefore we can predict
+ the Cmp result. */
+ switch (get_irn_opcode(a)) {
+ case iro_Cmp:
+ aa = get_Cmp_left(a);
+ ab = get_Cmp_right(a);
+ proj_nr = get_Proj_proj(n);
+
+ if (aa == ab) { /* 1.: */
+ /* This is a trick with the bits used for encoding the Cmp
+ Proj numbers, the following statement is not the same:
+ return new_tarval_from_long (proj_nr == Eq, mode_b) */
+ return new_tarval_from_long (proj_nr & Eq, mode_b);
+ } else {
+ tarval *taa = computed_value (aa);
+ tarval *tab = computed_value (ab);
+
+ if ((taa != tarval_bad) && (tab != tarval_bad)) { /* 2.: */
+ /* strange checks... */
+ pnc_number flags = tarval_cmp (taa, tab);
+ if (flags != False) {
+ return new_tarval_from_long (proj_nr & flags, mode_b);
+ }
+ } else { /* check for 3.: */
+ ir_node *aaa = skip_Id(skip_Proj(aa));
+ ir_node *aba = skip_Id(skip_Proj(ab));
+
+ if ( ( (/* aa is ProjP and aaa is Alloc */
+ (get_irn_op(aa) == op_Proj)
+ && (mode_is_reference(get_irn_mode(aa)))
+ && (get_irn_op(aaa) == op_Alloc))
+ && ( (/* ab is constant void */
+ (get_irn_op(ab) == op_Const)
+ && (mode_is_reference(get_irn_mode(ab)))
+ && (get_Const_tarval(ab) == get_mode_null(get_irn_mode(ab))))
+ || (/* ab is other Alloc */
+ (get_irn_op(ab) == op_Proj)
+ && (mode_is_reference(get_irn_mode(ab)))
+ && (get_irn_op(aba) == op_Alloc)
+ && (aaa != aba))))
+ || (/* aa is void and aba is Alloc */
+ (get_irn_op(aa) == op_Const)
+ && (mode_is_reference(get_irn_mode(aa)))
+ && (get_Const_tarval(aa) == get_mode_null(get_irn_mode(aa)))
+ && (get_irn_op(ab) == op_Proj)
+ && (mode_is_reference(get_irn_mode(ab)))
+ && (get_irn_op(aba) == op_Alloc)))
+ /* 3.: */
+ return new_tarval_from_long (proj_nr & Ne, mode_b);
+ }
+ }
+ break;
+
+ case iro_DivMod:
+ /* compute either the Div or the Mod part */
+ proj_nr = get_Proj_proj(n);
+ if (proj_nr == pn_DivMod_res_div)
+ return do_computed_value_Div(get_DivMod_left(a), get_DivMod_right(a));
+ else if (proj_nr == pn_DivMod_res_mod)
+ return do_computed_value_Mod(get_DivMod_left(a), get_DivMod_right(a));
+ break;
+
+ case iro_Div:
+ if (get_Proj_proj(n) == pn_Div_res)
+ return computed_value(a);
+ break;
+
+ case iro_Mod:
+ if (get_Proj_proj(n) == pn_Mod_res)
+ return computed_value(a);
+ break;
+
+ default:
+ return tarval_bad;
+ }
+ return tarval_bad;
+}
+
+/**
+ * If the parameter n can be computed, return its value, else tarval_bad.
+ * Performs constant folding.
+ *
+ * @param n The node this should be evaluated
+ */
+tarval *computed_value(ir_node *n)
+{
+ if (n->op->computed_value)
+ return n->op->computed_value(n);
+ return tarval_bad;
+}
+
+/**
+ * set the default computed_value evaluator
+ */
+static ir_op *firm_set_default_computed_value(ir_op *op)
+{
+#define CASE(a) \
+ case iro_##a: \
+ op->computed_value = computed_value_##a; \
+ break
+
+ switch (op->code) {
+ CASE(Const);
+ CASE(SymConst);
+ CASE(Add);
+ CASE(Sub);
+ CASE(Minus);
+ CASE(Mul);
+ CASE(Quot);
+ CASE(Div);
+ CASE(Mod);
+ CASE(Abs);
+ CASE(And);
+ CASE(Or);
+ CASE(Eor);
+ CASE(Not);
+ CASE(Shl);
+ CASE(Shr);
+ CASE(Shrs);
+ CASE(Rot);
+ CASE(Conv);
+ CASE(Proj);
+ default:
+ op->computed_value = NULL;
+ }
+
+ return op;
+#undef CASE
+}
+
+#if 0
+/* returns 1 if the a and b are pointers to different locations. */
+static bool
+different_identity (ir_node *a, ir_node *b)
+{
+ assert (mode_is_reference(get_irn_mode (a))
+ && mode_is_reference(get_irn_mode (b)));
+
+ if (get_irn_op (a) == op_Proj && get_irn_op(b) == op_Proj) {
+ ir_node *a1 = get_Proj_pred (a);
+ ir_node *b1 = get_Proj_pred (b);
+ if (a1 != b1 && get_irn_op (a1) == op_Alloc
+ && get_irn_op (b1) == op_Alloc)
+ return 1;
+ }
+ return 0;
+}
+#endif
+
+static ir_node *equivalent_node_Block(ir_node *n)
+{
+ ir_node *oldn = n;
+
+ /* The Block constructor does not call optimize, but mature_immBlock
+ calls the optimization. */
+ assert(get_Block_matured(n));
+
+ /* Straightening: a single entry Block following a single exit Block
+ can be merged, if it is not the Start block. */
+ /* !!! Beware, all Phi-nodes of n must have been optimized away.
+ This should be true, as the block is matured before optimize is called.
+ But what about Phi-cycles with the Phi0/Id that could not be resolved?
+ Remaining Phi nodes are just Ids. */
+ if ((get_Block_n_cfgpreds(n) == 1) &&
+ (get_irn_op(get_Block_cfgpred(n, 0)) == op_Jmp)) {
+ ir_node *predblock = get_nodes_block(get_Block_cfgpred(n, 0));
+ if (predblock == oldn) {
+ /* Jmp jumps into the block it is in -- deal self cycle. */
+ n = new_Bad();
+ DBG_OPT_DEAD(oldn, n);
+ } else if (get_opt_control_flow_straightening()) {
+ n = predblock;
+ DBG_OPT_STG(oldn, n);
+ }
+ }
+ else if ((get_Block_n_cfgpreds(n) == 1) &&
+ (get_irn_op(skip_Proj(get_Block_cfgpred(n, 0))) == op_Cond)) {
+ ir_node *predblock = get_nodes_block(get_Block_cfgpred(n, 0));
+ if (predblock == oldn) {
+ /* Jmp jumps into the block it is in -- deal self cycle. */
+ n = new_Bad();
+ DBG_OPT_DEAD(oldn, n);
+ }
+ }
+ else if ((get_Block_n_cfgpreds(n) == 2) &&
+ (get_opt_control_flow_weak_simplification())) {
+ /* Test whether Cond jumps twice to this block
+ @@@ we could do this also with two loops finding two preds from several ones. */
+ ir_node *a = get_Block_cfgpred(n, 0);
+ ir_node *b = get_Block_cfgpred(n, 1);
+
+ if ((get_irn_op(a) == op_Proj) &&
+ (get_irn_op(b) == op_Proj) &&
+ (get_Proj_pred(a) == get_Proj_pred(b)) &&
+ (get_irn_op(get_Proj_pred(a)) == op_Cond) &&
+ (get_irn_mode(get_Cond_selector(get_Proj_pred(a))) == mode_b)) {
+ /* Also a single entry Block following a single exit Block. Phis have
+ twice the same operand and will be optimized away. */
+ n = get_nodes_block(a);
+ DBG_OPT_IFSIM(oldn, a, b, n);
+ }
+ } else if (get_opt_unreachable_code() &&
+ (n != current_ir_graph->start_block) &&
+ (n != current_ir_graph->end_block) ) {
+ int i;
+ /* If all inputs are dead, this block is dead too, except if it is
+ the start or end block. This is a step of unreachable code
+ elimination */
+ for (i = 0; i < get_Block_n_cfgpreds(n); i++) {
+ if (!is_Bad(get_Block_cfgpred(n, i))) break;
+ }
+ if (i == get_Block_n_cfgpreds(n))
+ n = new_Bad();
+ }
+
+ return n;
+}
+
+/**
+ * Returns a equivalent node for a Jmp, a Bad :-)
+ * Of course this only happens if the Block of the Jmp is Bad.
+ */
+static ir_node *equivalent_node_Jmp(ir_node *n)
+{
+ /* GL: Why not same for op_Raise?? */
+ /* unreachable code elimination */
+ if (is_Bad(get_nodes_block(n)))
+ n = new_Bad();
+
+ return n;
+}
+
+static ir_node *equivalent_node_Cond(ir_node *n)
+{
+ /* We do not evaluate Cond here as we replace it by a new node, a Jmp.
+ See cases for iro_Cond and iro_Proj in transform_node. */
+ return n;
+}
+
+/**
+ * Use algebraic simplification a v a = a.
+ */
+static ir_node *equivalent_node_Or(ir_node *n)
+{
+ ir_node *oldn = n;
+
+ ir_node *a = get_Or_left(n);
+ ir_node *b = get_Or_right(n);
+
+ /* remove a v a */
+ if (a == b) {
+ n = a;
+
+ DBG_OPT_ALGSIM1(oldn, a, b, n);
+ }
+
+ return n;
+}
+
+/**
+ * optimize operations that are commutative and have neutral 0,
+ * so a op 0 = 0 op a = a.
+ */
+static ir_node *equivalent_node_neutral_zero(ir_node *n)
+{
+ ir_node *oldn = n;
+
+ ir_node *a = get_binop_left(n);
+ ir_node *b = get_binop_right(n);
+
+ tarval *tv;
+ ir_node *on;
+
+ /* After running compute_node there is only one constant predecessor.
+ Find this predecessors value and remember the other node: */
+ if ((tv = computed_value(a)) != tarval_bad) {
+ on = b;
+ } else if ((tv = computed_value(b)) != tarval_bad) {
+ on = a;
+ } else
+ return n;
+
+ /* If this predecessors constant value is zero, the operation is
+ unnecessary. Remove it: */
+ if (classify_tarval (tv) == TV_CLASSIFY_NULL) {
+ n = on;
+
+ DBG_OPT_ALGSIM1(oldn, a, b, n);
+ }
+
+ return n;
+}
+
+#define equivalent_node_Add equivalent_node_neutral_zero
+#define equivalent_node_Eor equivalent_node_neutral_zero
+
+/**
+ * optimize operations that are not commutative but have neutral 0 on left,
+ * so a op 0 = a.
+ */
+static ir_node *equivalent_node_left_zero(ir_node *n)
+{
+ ir_node *oldn = n;
+
+ ir_node *a = get_binop_left(n);
+ ir_node *b = get_binop_right(n);
+
+ if (classify_tarval(computed_value(b)) == TV_CLASSIFY_NULL) {
+ n = a;
+
+ DBG_OPT_ALGSIM1(oldn, a, b, n);
+ }
+
+ return n;
+}
+
+#define equivalent_node_Sub equivalent_node_left_zero
+#define equivalent_node_Shl equivalent_node_left_zero
+#define equivalent_node_Shr equivalent_node_left_zero
+#define equivalent_node_Shrs equivalent_node_left_zero
+#define equivalent_node_Rot equivalent_node_left_zero
+
+/**
+ * Er, a "symmetic unop", ie op(op(n)) = n.
+ */
+static ir_node *equivalent_node_symmetric_unop(ir_node *n)
+{
+ ir_node *oldn = n;
+ ir_node *pred = get_unop_op(n);
+
+ /* optimize symmetric unop */
+ if (get_irn_op(pred) == get_irn_op(n)) {
+ n = get_unop_op(pred);
+ DBG_OPT_ALGSIM2(oldn, pred, n);
+ }
+ return n;
+}
+
+/* NotNot x == x */
+#define equivalent_node_Not equivalent_node_symmetric_unop
+
+/* --x == x */ /* ??? Is this possible or can --x raise an
+ out of bounds exception if min =! max? */
+#define equivalent_node_Minus equivalent_node_symmetric_unop
+
+/**
+ * Optimize a * 1 = 1 * a = a.
+ */
+static ir_node *equivalent_node_Mul(ir_node *n)
+{
+ ir_node *oldn = n;
+
+ ir_node *a = get_Mul_left(n);
+ ir_node *b = get_Mul_right(n);
+
+ /* Mul is commutative and has again an other neutral element. */
+ if (classify_tarval (computed_value (a)) == TV_CLASSIFY_ONE) {
+ n = b;
+ DBG_OPT_ALGSIM1(oldn, a, b, n);
+ } else if (classify_tarval (computed_value (b)) == TV_CLASSIFY_ONE) {
+ n = a;
+ DBG_OPT_ALGSIM1(oldn, a, b, n);
+ }
+ return n;
+}
+
+/**
+ * Optimize a / 1 = a.
+ */
+static ir_node *equivalent_node_Div(ir_node *n)
+{
+ ir_node *a = get_Div_left(n);
+ ir_node *b = get_Div_right(n);
+
+ /* Div is not commutative. */
+ if (classify_tarval(computed_value(b)) == TV_CLASSIFY_ONE) { /* div(x, 1) == x */
+ /* Turn Div into a tuple (mem, bad, a) */
+ ir_node *mem = get_Div_mem(n);
+ turn_into_tuple(n, 3);
+ set_Tuple_pred(n, pn_Div_M, mem);
+ set_Tuple_pred(n, pn_Div_X_except, new_Bad()); /* no exception */
+ set_Tuple_pred(n, pn_Div_res, a);
+ }
+ return n;
+}
+
+/**
+ * Optimize a / 1 = a.
+ */
+static ir_node *equivalent_node_DivMod(ir_node *n)
+{
+ ir_node *a = get_DivMod_left(n);
+ ir_node *b = get_DivMod_right(n);
+
+ /* Div is not commutative. */
+ if (classify_tarval(computed_value(b)) == TV_CLASSIFY_ONE) { /* div(x, 1) == x */
+ /* Turn DivMod into a tuple (mem, bad, a, 0) */
+ ir_node *mem = get_Div_mem(n);
+ ir_mode *mode = get_irn_mode(b);
+
+ turn_into_tuple(n, 4);
+ set_Tuple_pred(n, pn_DivMod_M, mem);
+ set_Tuple_pred(n, pn_DivMod_X_except, new_Bad()); /* no exception */
+ set_Tuple_pred(n, pn_DivMod_res_div, a);
+ set_Tuple_pred(n, pn_DivMod_res_mod, new_Const(mode, get_mode_null(mode)));
+ }
+ return n;
+}
+
+/**
+ * Optimize a & 0b1...1 = 0b1...1 & a = a & a = a.
+ */
+static ir_node *equivalent_node_And(ir_node *n)
+{
+ ir_node *oldn = n;
+
+ ir_node *a = get_And_left(n);
+ ir_node *b = get_And_right(n);
+
+ if (a == b) {
+ n = a; /* And has it's own neutral element */
+ } else if (classify_tarval(computed_value(a)) == TV_CLASSIFY_ALL_ONE) {
+ n = b;
+ DBG_OPT_ALGSIM1(oldn, a, b, n);
+ } else if (classify_tarval(computed_value(b)) == TV_CLASSIFY_ALL_ONE) {
+ n = a;
+ DBG_OPT_ALGSIM1(oldn, a, b, n);
+ }
+ return n;
+}
+
+/**
+ * Try to remove useless conv's:
+ */
+static ir_node *equivalent_node_Conv(ir_node *n)
+{
+ ir_node *oldn = n;
+ ir_node *a = get_Conv_op(n);
+ ir_node *b;
+
+ ir_mode *n_mode = get_irn_mode(n);
+ ir_mode *a_mode = get_irn_mode(a);
+
+ if (n_mode == a_mode) { /* No Conv necessary */
+ n = a;
+ DBG_OPT_ALGSIM3(oldn, a, n);
+ } else if (get_irn_op(a) == op_Conv) { /* Conv(Conv(b)) */
+ ir_mode *b_mode;
+
+ b = get_Conv_op(a);
+ n_mode = get_irn_mode(n);
+ b_mode = get_irn_mode(b);
+
+ if (n_mode == b_mode) {
+ if (n_mode == mode_b) {
+ n = b; /* Convb(Conv*(xxxb(...))) == xxxb(...) */
+ DBG_OPT_ALGSIM1(oldn, a, b, n);
+ }
+ else if (mode_is_int(n_mode) || mode_is_character(n_mode)) {
+ if (smaller_mode(b_mode, a_mode)){
+ n = b; /* ConvS(ConvL(xxxS(...))) == xxxS(...) */
+ DBG_OPT_ALGSIM1(oldn, a, b, n);
+ }
+ }
+ }
+ }
+ return n;
+}
+
+static ir_node *equivalent_node_Phi(ir_node *n)
+{
+ /* Several optimizations:
+ - no Phi in start block.
+ - remove Id operators that are inputs to Phi
+ - fold Phi-nodes, iff they have only one predecessor except
+ themselves.
+ */
+ int i, n_preds;
+
+ ir_node *oldn = n;
+ ir_node *block = NULL; /* to shutup gcc */
+ ir_node *first_val = NULL; /* to shutup gcc */
+ ir_node *scnd_val = NULL; /* to shutup gcc */
+
+ if (!get_opt_normalize()) return n;
+
+ n_preds = get_Phi_n_preds(n);
+
+ block = get_nodes_block(n);
+ /* @@@ fliegt 'raus, sollte aber doch immer wahr sein!!!
+ assert(get_irn_arity(block) == n_preds && "phi in wrong block!"); */
+ if ((is_Bad(block)) || /* Control dead */
+ (block == current_ir_graph->start_block)) /* There should be no Phi nodes */
+ return new_Bad(); /* in the Start Block. */
+
+ if (n_preds == 0) return n; /* Phi of dead Region without predecessors. */
+
+#if 0
+ /* first we test for a special case: */
+ /* Confirm is a special node fixing additional information for a
+ value that is known at a certain point. This is useful for
+ dataflow analysis. */
+ if (n_preds == 2) {
+ ir_node *a = get_Phi_pred(n, 0);
+ ir_node *b = get_Phi_pred(n, 1);
+ if ( (get_irn_op(a) == op_Confirm)
+ && (get_irn_op(b) == op_Confirm)
+ && follow_Id (get_irn_n(a, 0) == get_irn_n(b, 0))
+ && (get_irn_n(a, 1) == get_irn_n (b, 1))
+ && (a->data.num == (~b->data.num & irpn_True) )) {
+ return get_irn_n(a, 0);
+ }
+ }
+#endif
+
+ /* If the Block has a Bad pred, we also have one. */
+ for (i = 0; i < n_preds; ++i)
+ if (is_Bad (get_Block_cfgpred(block, i)))
+ set_Phi_pred(n, i, new_Bad());
+
+ /* Find first non-self-referencing input */
+ for (i = 0; i < n_preds; ++i) {
+ first_val = get_Phi_pred(n, i);
+ if ( (first_val != n) /* not self pointer */
+#if 1
+ && (get_irn_op(first_val) != op_Bad)
+#endif
+ ) { /* value not dead */
+ break; /* then found first value. */
+ }
+ }
+
+ /* A totally Bad or self-referencing Phi (we didn't break the above loop) */
+ if (i >= n_preds) { return new_Bad(); }
+
+ scnd_val = NULL;
+
+ /* follow_Id () for rest of inputs, determine if any of these
+ are non-self-referencing */
+ while (++i < n_preds) {
+ scnd_val = get_Phi_pred(n, i);
+ if ( (scnd_val != n)
+ && (scnd_val != first_val)
+#if 1
+ && (get_irn_op(scnd_val) != op_Bad)
+#endif
+ ) {
+ break;
+ }
+ }
+
+ /* Fold, if no multiple distinct non-self-referencing inputs */
+ if (i >= n_preds) {
+ n = first_val;
+ DBG_OPT_PHI(oldn, first_val, n);
+ } else {
+ /* skip the remaining Ids (done in get_Phi_pred). */
+ /* superfluous, since we walk all to propagate Block's Bads.
+ while (++i < n_preds) get_Phi_pred(n, i); */
+ }
+ return n;
+}
+
+/**
+ * optimize Proj(Tuple) and gigo for ProjX in Bad block
+ */
+static ir_node *equivalent_node_Proj(ir_node *n)
+{
+ ir_node *oldn = n;
+
+ ir_node *a = get_Proj_pred(n);
+
+ if ( get_irn_op(a) == op_Tuple) {
+ /* Remove the Tuple/Proj combination. */
+ if ( get_Proj_proj(n) <= get_Tuple_n_preds(a) ) {
+ n = get_Tuple_pred(a, get_Proj_proj(n));
+ DBG_OPT_TUPLE(oldn, a, n);
+ } else {
+ assert(0); /* This should not happen! */
+ n = new_Bad();
+ }
+ } else if (get_irn_mode(n) == mode_X &&
+ is_Bad(get_nodes_block(n))) {
+ /* Remove dead control flow -- early gigo. */
+ n = new_Bad();
+ }
+ return n;
+}
+
+/**
+ * Remove Id's.
+ */
+static ir_node *equivalent_node_Id(ir_node *n)
+{
+ ir_node *oldn = n;
+
+ n = follow_Id(n);
+ DBG_OPT_ID(oldn, n);
+ return n;
+}
+
+/**
+ * equivalent_node() returns a node equivalent to input n. It skips all nodes that
+ * perform no actual computation, as, e.g., the Id nodes. It does not create
+ * new nodes. It is therefore safe to free n if the node returned is not n.
+ * If a node returns a Tuple we can not just skip it. If the size of the
+ * in array fits, we transform n into a tuple (e.g., Div).
+ */
+ir_node *
+equivalent_node(ir_node *n)
+{
+ if (n->op->equivalent_node)
+ return n->op->equivalent_node(n);
+ return n;
+}
+
+/**
+ * set the default equivalent node operation
+ */
+static ir_op *firm_set_default_equivalent_node(ir_op *op)
+{
+#define CASE(a) \
+ case iro_##a: \
+ op->equivalent_node = equivalent_node_##a; \
+ break
+
+ switch (op->code) {
+ CASE(Block);
+ CASE(Jmp);
+ CASE(Cond);
+ CASE(Or);
+ CASE(Add);
+ CASE(Eor);
+ CASE(Sub);
+ CASE(Shl);
+ CASE(Shr);
+ CASE(Shrs);
+ CASE(Rot);
+ CASE(Not);
+ CASE(Minus);
+ CASE(Mul);
+ CASE(Div);
+ CASE(DivMod);
+ CASE(And);
+ CASE(Conv);
+ CASE(Phi);
+ CASE(Proj);
+ CASE(Id);
+ default:
+ op->equivalent_node = NULL;
+ }
+
+ return op;
+#undef CASE
+}
+
+/**
+ * Do node specific optimizations of nodes predecessors.
+ */
+static void
+optimize_preds(ir_node *n) {
+ ir_node *a = NULL, *b = NULL;
+
+ /* get the operands we will work on for simple cases. */
+ if (is_binop(n)) {
+ a = get_binop_left(n);
+ b = get_binop_right(n);
+ } else if (is_unop(n)) {
+ a = get_unop_op(n);
+ }
+
+ switch (get_irn_opcode(n)) {
+
+ case iro_Cmp:
+ /* We don't want Cast as input to Cmp. */
+ if (get_irn_op(a) == op_Cast) {
+ a = get_Cast_op(a);
+ set_Cmp_left(n, a);
+ }
+ if (get_irn_op(b) == op_Cast) {
+ b = get_Cast_op(b);
+ set_Cmp_right(n, b);
+ }
+ break;
+
+ default: break;
+ } /* end switch */
+}
+
+static ir_node *transform_node_Mul(ir_node *n)
+{
+ return arch_dep_replace_mul_with_shifts(n);
+}
+
+static ir_node *transform_node_Div(ir_node *n)
+{
+ tarval *tv = computed_value(n);
+ ir_node *value = n;
+
+ /* BEWARE: it is NOT possible to optimize a/a to 1, as this may cause a exception */
+
+ if (tv != tarval_bad)
+ value = new_Const(get_tarval_mode(tv), tv);
+ else /* Try architecture dependand optimization */
+ value = arch_dep_replace_div_with_shifts(n);
+
+ if (value != n) {
+ /* Turn Div into a tuple (mem, bad, value) */
+ ir_node *mem = get_Div_mem(n);
+
+ turn_into_tuple(n, 3);
+ set_Tuple_pred(n, pn_Div_M, mem);
+ set_Tuple_pred(n, pn_Div_X_except, new_Bad());
+ set_Tuple_pred(n, pn_Div_res, value);
+ }
+ return n;
+}
+
+static ir_node *transform_node_Mod(ir_node *n)
+{
+ tarval *tv = computed_value(n);
+ ir_node *value = n;
+
+ /* BEWARE: it is NOT possible to optimize a%a to 0, as this may cause a exception */
+
+ if (tv != tarval_bad)
+ value = new_Const(get_tarval_mode(tv), tv);
+ else /* Try architecture dependand optimization */
+ value = arch_dep_replace_mod_with_shifts(n);
+
+ if (value != n) {
+ /* Turn Mod into a tuple (mem, bad, value) */
+ ir_node *mem = get_Mod_mem(n);
+
+ turn_into_tuple(n, 3);
+ set_Tuple_pred(n, pn_Mod_M, mem);
+ set_Tuple_pred(n, pn_Mod_X_except, new_Bad());
+ set_Tuple_pred(n, pn_Mod_res, value);
+ }
+ return n;
+}
+
+static ir_node *transform_node_DivMod(ir_node *n)
+{
+ int evaluated = 0;
+
+ ir_node *a = get_DivMod_left(n);
+ ir_node *b = get_DivMod_right(n);
+ ir_mode *mode = get_irn_mode(a);
+ tarval *ta = value_of(a);
+ tarval *tb = value_of(b);
+
+ if (!(mode_is_int(mode) && mode_is_int(get_irn_mode(b))))
+ return n;
+
+ /* BEWARE: it is NOT possible to optimize a/a to 1, as this may cause a exception */
+
+ if (tb != tarval_bad) {
+ if (tb == get_mode_one(get_tarval_mode(tb))) {
+ b = new_Const (mode, get_mode_null(mode));
+ evaluated = 1;
+ } else if (ta != tarval_bad) {
+ tarval *resa, *resb;
+ resa = tarval_div (ta, tb);
+ if (resa == tarval_bad) return n; /* Causes exception!!! Model by replacing through
+ Jmp for X result!? */
+ resb = tarval_mod (ta, tb);
+ if (resb == tarval_bad) return n; /* Causes exception! */
+ a = new_Const (mode, resa);
+ b = new_Const (mode, resb);
+ evaluated = 1;
+ }
+ else { /* Try architecture dependand optimization */
+ arch_dep_replace_divmod_with_shifts(&a, &b, n);
+ evaluated = a != NULL;
+ }
+ } else if (ta == get_mode_null(mode)) {
+ /* 0 / non-Const = 0 */
+ b = a;
+ evaluated = 1;
+ }
+
+ if (evaluated) { /* replace by tuple */
+ ir_node *mem = get_DivMod_mem(n);
+ turn_into_tuple(n, 4);
+ set_Tuple_pred(n, pn_DivMod_M, mem);
+ set_Tuple_pred(n, pn_DivMod_X_except, new_Bad()); /* no exception */
+ set_Tuple_pred(n, pn_DivMod_res_div, a);
+ set_Tuple_pred(n, pn_DivMod_res_mod, b);
+ assert(get_nodes_block(n));
+ }
+
+ return n;
+}
+
+static ir_node *transform_node_Cond(ir_node *n)
+{
+ /* Replace the Cond by a Jmp if it branches on a constant
+ condition. */
+ ir_node *jmp;
+ ir_node *a = get_Cond_selector(n);
+ tarval *ta = value_of(a);
+
+ if ((ta != tarval_bad) &&
+ (get_irn_mode(a) == mode_b) &&
+ (get_opt_unreachable_code())) {
+ /* It's a boolean Cond, branching on a boolean constant.
+ Replace it by a tuple (Bad, Jmp) or (Jmp, Bad) */
+ jmp = new_r_Jmp(current_ir_graph, get_nodes_block(n));
+ turn_into_tuple(n, 2);
+ if (ta == tarval_b_true) {
+ set_Tuple_pred(n, pn_Cond_false, new_Bad());
+ set_Tuple_pred(n, pn_Cond_true, jmp);
+ } else {
+ set_Tuple_pred(n, pn_Cond_false, jmp);
+ set_Tuple_pred(n, pn_Cond_true, new_Bad());
+ }
+ /* We might generate an endless loop, so keep it alive. */
+ add_End_keepalive(get_irg_end(current_ir_graph), get_nodes_block(n));
+ } else if ((ta != tarval_bad) &&
+ (get_irn_mode(a) == mode_Iu) &&
+ (get_Cond_kind(n) == dense) &&
+ (get_opt_unreachable_code())) {
+ /* I don't want to allow Tuples smaller than the biggest Proj.
+ Also this tuple might get really big...
+ I generate the Jmp here, and remember it in link. Link is used
+ when optimizing Proj. */
+ set_irn_link(n, new_r_Jmp(current_ir_graph, get_nodes_block(n)));
+ /* We might generate an endless loop, so keep it alive. */
+ add_End_keepalive(get_irg_end(current_ir_graph), get_nodes_block(n));
+ } else if ((get_irn_op(a) == op_Eor)
+ && (get_irn_mode(a) == mode_b)
+ && (classify_tarval(computed_value(get_Eor_right(a))) == TV_CLASSIFY_ONE)) {
+ /* The Eor is a negate. Generate a new Cond without the negate,
+ simulate the negate by exchanging the results. */
+ set_irn_link(n, new_r_Cond(current_ir_graph, get_nodes_block(n),
+ get_Eor_left(a)));
+ } else if ((get_irn_op(a) == op_Not)
+ && (get_irn_mode(a) == mode_b)) {
+ /* A Not before the Cond. Generate a new Cond without the Not,
+ simulate the Not by exchanging the results. */
+ set_irn_link(n, new_r_Cond(current_ir_graph, get_nodes_block(n),
+ get_Not_op(a)));
+ }
+ return n;
+}
+
+static ir_node *transform_node_Eor(ir_node *n)
+{
+ ir_node *a = get_Eor_left(n);
+ ir_node *b = get_Eor_right(n);
+
+ if ((get_irn_mode(n) == mode_b)
+ && (get_irn_op(a) == op_Proj)
+ && (get_irn_mode(a) == mode_b)
+ && (classify_tarval (computed_value (b)) == TV_CLASSIFY_ONE)
+ && (get_irn_op(get_Proj_pred(a)) == op_Cmp))
+ /* The Eor negates a Cmp. The Cmp has the negated result anyways! */
+ n = new_r_Proj(current_ir_graph, get_nodes_block(n), get_Proj_pred(a),
+ mode_b, get_negated_pnc(get_Proj_proj(a)));
+ else if ((get_irn_mode(n) == mode_b)
+ && (classify_tarval (computed_value (b)) == TV_CLASSIFY_ONE))
+ /* The Eor is a Not. Replace it by a Not. */
+ /* ????!!!Extend to bitfield 1111111. */
+ n = new_r_Not(current_ir_graph, get_nodes_block(n), a, mode_b);
- ir_node *a = NULL, *b = NULL; /* initialized to shut up gcc */
- tarval *ta = NULL, *tb = NULL; /* initialized to shut up gcc */
+ return n;
+}
- res = NULL;
+/**
+ * Transform a boolean Not.
+ */
+static ir_node *transform_node_Not(ir_node *n)
+{
+ ir_node *a = get_Not_op(n);
- /* get the operands we will work on for simple cases. */
- if (is_binop(n)) {
- a = get_binop_left(n);
- b = get_binop_right(n);
- } else if (is_unop(n)) {
- a = get_unop_op(n);
- }
+ if ( (get_irn_mode(n) == mode_b)
+ && (get_irn_op(a) == op_Proj)
+ && (get_irn_mode(a) == mode_b)
+ && (get_irn_op(get_Proj_pred(a)) == op_Cmp))
+ /* We negate a Cmp. The Cmp has the negated result anyways! */
+ n = new_r_Proj(current_ir_graph, get_nodes_block(n), get_Proj_pred(a),
+ mode_b, get_negated_pnc(get_Proj_proj(a)));
+
+ return n;
+}
- /* if the operands are constants, get the target value, else set it NULL.
- (a and b may be NULL if we treat a node that is no computation.) */
- ta = value_of (a);
- tb = value_of (b);
+/**
+ * Transform a Div/Mod/DivMod with a non-zero constant. Must be
+ * done here instead of equivalent node because in creates new
+ * nodes.
+ * Removes the exceptions and routes the memory to the initial mem.
+ *
+ * Further, it optimizes jump tables by removing all impossible cases.
+ */
+static ir_node *transform_node_Proj(ir_node *proj)
+{
+ ir_node *n = get_Proj_pred(proj);
+ ir_node *b;
+ tarval *tb;
+ long proj_nr;
- /* Perform the constant evaluation / computation. */
switch (get_irn_opcode(n)) {
- case iro_Const:
- res = get_Const_tarval(n);
- case iro_Add:
- if (ta && tb && (get_irn_mode(a) == get_irn_mode(b))
- && (get_irn_mode(a) != mode_p)) {
- res = tarval_add (ta, tb);
- }
- break;
- case iro_Sub:
- if (ta && tb && (get_irn_mode(a) == get_irn_mode(b))
- && (get_irn_mode(a) != mode_p)) {
- res = tarval_sub (ta, tb);
- } else if (a == b) {
- res = tarval_mode_null [get_irn_modecode (n)];
- }
- break;
- case iro_Minus:
- if (ta && mode_is_float(get_irn_mode(a)))
- res = tarval_neg (ta);
- break;
- case iro_Mul:
- if (ta && tb) /* tarval_mul tests for equivalent modes itself */ {
- res = tarval_mul (ta, tb);
- } else {
- /* a*0 = 0 or 0*b = 0:
- calls computed_value recursive and returns the 0 with proper
- mode. */
- tarval *v;
- if ( (tarval_classify ((v = computed_value (a))) == 0)
- || (tarval_classify ((v = computed_value (b))) == 0)) {
- res = v;
- }
- }
- break;
- case iro_Quot:
- /* This was missing in original implementation. Why? */
- if (ta && tb && (get_irn_mode(a) == get_irn_mode(b))) {
- if (tarval_classify(tb) == 0) {res = NULL; break;}
- res = tarval_quo(ta, tb);
- }
- break;
case iro_Div:
- /* This was missing in original implementation. Why? */
- if (ta && tb && (get_irn_mode(a) == get_irn_mode(b))) {
- if (tarval_classify(tb) == 0) {res = NULL; break;}
- res = tarval_div(ta, tb);
+ b = get_Div_right(n);
+ tb = computed_value(b);
+
+ if (tb != tarval_bad && classify_tarval(tb) != TV_CLASSIFY_NULL) { /* div(x, c) && c != 0 */
+ proj_nr = get_Proj_proj(proj);
+
+ if (proj_nr == pn_Div_X_except) {
+ /* we found an exception handler, remove it */
+ return new_Bad();
+ }
+ else {
+ /* the memory Proj can be removed */
+ ir_node *res = get_Div_mem(n);
+ set_Div_mem(n, get_irg_initial_mem(current_ir_graph));
+ if (proj_nr == pn_Div_M)
+ return res;
+ }
}
break;
case iro_Mod:
- /* This was missing in original implementation. Why? */
- if (ta && tb && (get_irn_mode(a) == get_irn_mode(b))) {
- if (tarval_classify(tb) == 0) {res = NULL; break;}
- res = tarval_mod(ta, tb);
- }
- break;
- /* for iro_DivMod see iro_Proj */
- case iro_Abs:
- if (ta)
- res = tarval_abs (ta);
- break;
- case iro_And:
- if (ta && tb) {
- res = tarval_and (ta, tb);
- } else {
- tarval *v;
- if ( (tarval_classify ((v = computed_value (a))) == 0)
- || (tarval_classify ((v = computed_value (b))) == 0)) {
- res = v;
+ b = get_Mod_right(n);
+ tb = computed_value(b);
+
+ if (tb != tarval_bad && classify_tarval(tb) != TV_CLASSIFY_NULL) { /* mod(x, c) && c != 0 */
+ proj_nr = get_Proj_proj(proj);
+
+ if (proj_nr == pn_Mod_X_except) {
+ /* we found an exception handler, remove it */
+ return new_Bad();
+ }
+ else {
+ /* the memory Proj can be removed */
+ ir_node *res = get_Mod_mem(n);
+ set_Mod_mem(n, get_irg_initial_mem(current_ir_graph));
+ if (proj_nr == pn_Mod_M)
+ return res;
}
}
break;
- case iro_Or:
- if (ta && tb) {
- res = tarval_or (ta, tb);
- } else {
- tarval *v;
- if ( (tarval_classify ((v = computed_value (a))) == -1)
- || (tarval_classify ((v = computed_value (b))) == -1)) {
- res = v;
+ case iro_DivMod:
+ b = get_DivMod_right(n);
+ tb = computed_value(b);
+
+ if (tb != tarval_bad && classify_tarval(tb) != TV_CLASSIFY_NULL) { /* DivMod(x, c) && c != 0 */
+ proj_nr = get_Proj_proj(proj);
+
+ if (proj_nr == pn_DivMod_X_except) {
+ /* we found an exception handler, remove it */
+ return new_Bad();
+ }
+ else {
+ /* the memory Proj can be removed */
+ ir_node *res = get_DivMod_mem(n);
+ set_DivMod_mem(n, get_irg_initial_mem(current_ir_graph));
+ if (proj_nr == pn_DivMod_M)
+ return res;
}
}
break;
- case iro_Eor: if (ta && tb) { res = tarval_eor (ta, tb); } break;
- case iro_Not: if (ta) { res = tarval_neg (ta); } break;
- case iro_Shl: if (ta && tb) { res = tarval_shl (ta, tb); } break;
- /* tarval_shr is faulty !! */
- case iro_Shr: if (ta && tb) { res = tarval_shr (ta, tb); } break;
- case iro_Shrs:if (ta && tb) { /*res = tarval_shrs (ta, tb)*/; } break;
- case iro_Rot: if (ta && tb) { /*res = tarval_rot (ta, tb)*/; } break;
- case iro_Conv:if (ta) { res = tarval_convert_to (ta, get_irn_mode (n)); }
- break;
- case iro_Proj: /* iro_Cmp */
- {
- ir_node *aa, *ab;
-
- a = get_Proj_pred(n);
- /* Optimize Cmp nodes.
- This performs a first step of unreachable code elimination.
- Proj can not be computed, but folding a Cmp above the Proj here is
- not as wasteful as folding a Cmp into a Tuple of 16 Consts of which
- only 1 is used.
- There are several case where we can evaluate a Cmp node:
- 1. The nodes compared are both the same. If we compare for
- equal, this will return true, else it will return false.
- This step relies on cse.
- 2. The predecessors of Cmp are target values. We can evaluate
- the Cmp.
- 3. The predecessors are Allocs or void* constants. Allocs never
- return NULL, they raise an exception. Therefore we can predict
- the Cmp result. */
- if (get_irn_op(a) == op_Cmp) {
- aa = get_Cmp_left(a);
- ab = get_Cmp_right(a);
- if (aa == ab) { /* 1.: */
- /* This is a tric with the bits used for encoding the Cmp
- Proj numbers, the following statement is not the same:
- res = tarval_from_long (mode_b, (get_Proj_proj(n) == Eq)): */
- res = tarval_from_long (mode_b, (get_Proj_proj(n) & irpn_Eq));
- } else {
- tarval *taa = computed_value (aa);
- tarval *tab = computed_value (ab);
- if (taa && tab) { /* 2.: */
- /* strange checks... */
- ir_pncmp flags = tarval_comp (taa, tab);
- if (flags != irpn_False) {
- res = tarval_from_long (mode_b, get_Proj_proj(n) & flags);
- }
- } else { /* check for 3.: */
- ir_node *aaa = skip_nop(skip_Proj(aa));
- ir_node *aba = skip_nop(skip_Proj(ab));
- if ( ( (/* aa is ProjP and aaa is Alloc */
- (get_irn_op(aa) == op_Proj)
- && (get_irn_mode(aa) == mode_p)
- && (get_irn_op(aaa) == op_Alloc))
- && ( (/* ab is constant void */
- (get_irn_op(ab) == op_Const)
- && (get_irn_mode(ab) == mode_p)
- && (get_Const_tarval(ab) == tarval_p_void))
- || (/* ab is other Alloc */
- (get_irn_op(ab) == op_Proj)
- && (get_irn_mode(ab) == mode_p)
- && (get_irn_op(aba) == op_Alloc)
- && (aaa != aba))))
- || (/* aa is void and aba is Alloc */
- (get_irn_op(aa) == op_Const)
- && (get_irn_mode(aa) == mode_p)
- && (get_Const_tarval(aa) == tarval_p_void)
- && (get_irn_op(ab) == op_Proj)
- && (get_irn_mode(ab) == mode_p)
- && (get_irn_op(aba) == op_Alloc)))
- /* 3.: */
- res = tarval_from_long (mode_b, get_Proj_proj(n) & irpn_Ne);
- }
- }
- } else if (get_irn_op(a) == op_DivMod) {
- ta = value_of(get_DivMod_left(a));
- tb = value_of(get_DivMod_right(a));
- if (ta && tb && (get_irn_mode(a) == get_irn_mode(b))) {
- if (tarval_classify(tb) == 0) {res = NULL; break;}
- if (get_Proj_proj(n)== 0) /* Div */
- res = tarval_div(ta, tb);
- else /* Mod */
- res = tarval_mod(ta, tb);
- }
- } else {
- /* printf(" # comp_val: Proj node, not optimized\n"); */
+
+ case iro_Cond:
+ if (get_opt_unreachable_code()) {
+ b = get_Cond_selector(n);
+ tb = computed_value(b);
+
+ if (tb != tarval_bad && mode_is_int(get_tarval_mode(tb))) {
+ /* we have a constant switch */
+ long num = get_Proj_proj(proj);
+
+ if (num != get_Cond_defaultProj(n)) { /* we cannot optimize default Proj's yet */
+ if (get_tarval_long(tb) == num) {
+ /* Do NOT create a jump here, or we will have 2 control flow ops
+ * in a block. This case is optimized away in optimize_cf(). */
+ return proj;
+ }
+ else
+ return new_Bad();
+ }
}
}
- break;
- default: ;
- }
+ return proj;
- return res;
-} /* compute node */
+ case iro_Tuple:
+ /* should not happen, but if it does will be optimized away */
+ break;
+ default:
+ /* do nothing */
+ return proj;
+ }
+ /* we have added a Tuple, optimize it for the current Proj away */
+ return equivalent_node_Proj(proj);
+}
-/* returns 1 if the a and b are pointers to different locations. */
-bool
-different_identity (ir_node *a, ir_node *b)
+/**
+ * returns the operands of a commutative bin-op, if one operand is
+ * a const, it is returned as the second one.
+ */
+static void get_comm_Binop_Ops(ir_node *binop, ir_node **a, ir_node **c)
{
- assert (get_irn_mode (a) == mode_p
- && get_irn_mode (b) == mode_p);
+ ir_node *op_a = get_binop_left(binop);
+ ir_node *op_b = get_binop_right(binop);
- if (get_irn_op (a) == op_Proj && get_irn_op(b) == op_Proj) {
- ir_node *a1 = get_Proj_pred (a);
- ir_node *b1 = get_Proj_pred (b);
- if (a1 != b1 && get_irn_op (a1) == op_Alloc
- && get_irn_op (b1) == op_Alloc)
- return 1;
+ assert(is_op_commutative(get_irn_op(binop)));
+
+ if (get_irn_op(op_a) == op_Const) {
+ *a = op_b;
+ *c = op_a;
+ }
+ else {
+ *a = op_a;
+ *c = op_b;
}
- return 0;
}
-
-/* equivalent_node returns a node equivalent to N. It skips all nodes that
- perform no actual computation, as, e.g., the Id nodes. It does not create
- new nodes. It is therefore safe to free N if the node returned is not N.
- If a node returns a Tuple we can not just skip it. If the size of the
- in array fits, we transform n into a tuple (e.g., Div). */
-static ir_node *
-equivalent_node (ir_node *n)
+/**
+ * Optimize a Or(And(Or(And(v,c4),c3),c2),c1) pattern if possible.
+ * Such pattern may arise in bitfield stores.
+ *
+ * value c4 value c4 & c2
+ * AND c3 AND c1 | c3
+ * OR c2 ===> OR
+ * AND c1
+ * OR
+ */
+static ir_node *transform_node_Or(ir_node *or)
{
- int ins;
- ir_node *a = NULL; /* to shutup gcc */
- ir_node *b = NULL; /* to shutup gcc */
- ir_node *c = NULL; /* to shutup gcc */
+ ir_node *and, *c1;
+ ir_node *or_l, *c2;
+ ir_node *and_l, *c3;
+ ir_node *value, *c4;
+ ir_node *new_and, *new_const, *block;
+ ir_mode *mode = get_irn_mode(or);
+
+ tarval *tv1, *tv2, *tv3, *tv4, *tv, *n_tv4, *n_tv2;
+
+ get_comm_Binop_Ops(or, &and, &c1);
+ if ((get_irn_op(c1) != op_Const) || (get_irn_op(and) != op_And))
+ return or;
+
+ get_comm_Binop_Ops(and, &or_l, &c2);
+ if ((get_irn_op(c2) != op_Const) || (get_irn_op(or_l) != op_Or))
+ return or;
+
+ get_comm_Binop_Ops(or_l, &and_l, &c3);
+ if ((get_irn_op(c3) != op_Const) || (get_irn_op(and_l) != op_And))
+ return or;
+
+ get_comm_Binop_Ops(and_l, &value, &c4);
+ if (get_irn_op(c4) != op_Const)
+ return or;
+
+ /* ok, found the pattern, check for conditions */
+ assert(mode == get_irn_mode(and));
+ assert(mode == get_irn_mode(or_l));
+ assert(mode == get_irn_mode(and_l));
+
+ tv1 = get_Const_tarval(c1);
+ tv2 = get_Const_tarval(c2);
+ tv3 = get_Const_tarval(c3);
+ tv4 = get_Const_tarval(c4);
+
+ tv = tarval_or(tv4, tv2);
+ if (classify_tarval(tv) != TV_CLASSIFY_ALL_ONE) {
+ /* have at least one 0 at the same bit position */
+ return or;
+ }
- ins = get_irn_arity (n);
+ n_tv4 = tarval_not(tv4);
+ if (tv3 != tarval_and(tv3, n_tv4)) {
+ /* bit in the or_mask is outside the and_mask */
+ return or;
+ }
- /* get the operands we will work on */
- if (is_binop(n)) {
- a = get_binop_left(n);
- b = get_binop_right(n);
- } else if (is_unop(n)) {
- a = get_unop_op(n);
+ n_tv2 = tarval_not(tv2);
+ if (tv1 != tarval_and(tv1, n_tv2)) {
+ /* bit in the or_mask is outside the and_mask */
+ return or;
}
- /* skip unnecessary nodes. */
- switch (get_irn_opcode (n)) {
- case iro_Block:
- {
- /* The Block constructor does not call optimize, but mature_block
- calls the optimization. */
- assert(get_Block_matured(n));
-
- /* A single entry Block following a single exit Block can be merged,
- if it is not the Start block. */
- /* !!! Beware, all Phi-nodes of n must have been optimized away.
- This should be true, as the block is matured before optimize is called.
- But what about Phi-cycles with the Phi0/Id that could not be resolved? */
- if (get_Block_n_cfgpreds(n) == 1
- && get_irn_op(get_Block_cfgpred(n, 0)) == op_Jmp) {
- n = get_nodes_Block(get_Block_cfgpred(n, 0));
-
- } else if ((n != current_ir_graph->start_block) &&
- (n != current_ir_graph->end_block) ) {
- int i;
- /* If all inputs are dead, this block is dead too, except if it is
- the start or end block. This is a step of unreachable code
- elimination */
- for (i = 0; i < get_Block_n_cfgpreds(n); i++) {
- if (!is_Bad(get_Block_cfgpred(n, i))) break;
- }
- if (i == get_Block_n_cfgpreds(n))
- n = new_Bad();
- }
- }
- break;
+ /* ok, all conditions met */
+ block = get_nodes_block(or);
- case iro_Jmp: /* GL: Why not same for op_Raise?? */
- /* unreachable code elimination */
- if (is_Bad(get_nodes_Block(n))) n = new_Bad();
- break;
- /* We do not evaluate Cond here as we replace it by a new node, a Jmp.
- See cases for iro_Cond and iro_Proj in transform_node. */
- /** remove stuff as x+0, x*1 x&true ... constant expression evaluation **/
- case iro_Or: if (a == b) {n = a; break;}
- case iro_Add:
- case iro_Eor:
- { tarval *tv;
- ir_node *on;
- /* After running compute_node there is only one constant predecessor.
- Find this predecessors value and remember the other node: */
- if ((tv = computed_value (a))) {
- on = b;
- } else if ((tv = computed_value (b))) {
- on = a;
- } else break;
-
- /* If this predecessors constant value is zero, the operation is
- unnecessary. Remove it: */
- if (tarval_classify (tv) == 0) {
- n = on;
- }
- }
- break;
- case iro_Sub:
- case iro_Shl:
- case iro_Shr:
- case iro_Shrs:
- case iro_Rot:
- /* these operations are not commutative. Test only one predecessor. */
- if (tarval_classify (computed_value (b)) == 0) {
- n = a;
- /* Test if b > #bits of a ==> return 0 / divide b by #bits
- --> transform node? */
- }
- break;
- case iro_Not: /* NotNot x == x */
- case iro_Minus: /* --x == x */ /* ??? Is this possible or can --x raise an
- out of bounds exception if min =! max? */
- if (get_irn_op(get_unop_op(n)) == get_irn_op(n))
- n = get_unop_op(get_unop_op(n));
- break;
- case iro_Mul:
- /* Mul is commutative and has again an other neutral element. */
- if (tarval_classify (computed_value (a)) == 1) {
- n = b;
- } else if (tarval_classify (computed_value (b)) == 1) {
- n = a;
- }
- break;
- case iro_Div:
- /* Div is not commutative. */
- if (tarval_classify (computed_value (b)) == 1) { /* div(x, 1) == x */
- /* Turn Div into a tuple (mem, bad, a) */
- ir_node *mem = get_Div_mem(n);
- turn_into_tuple(n, 3);
- set_Tuple_pred(n, 0, mem);
- set_Tuple_pred(n, 1, new_Bad());
- set_Tuple_pred(n, 2, a);
- }
- break;
- /* GL: Why are they skipped? DivMod allocates new nodes --> it's
- teated in transform node.
- case iro_Mod, Quot, DivMod
- */
- case iro_And:
- if (a == b) n = a;
- /* And has it's own neutral element */
- else if (tarval_classify (computed_value (a)) == -1) {
- n = b;
- } else if (tarval_classify (computed_value (b)) == -1) {
- n = a;
- }
- break;
- case iro_Conv:
- if (get_irn_mode(n) == get_irn_mode(a)) { /* No Conv necessary */
- n = a;
- } else if (get_irn_mode(n) == mode_b) {
- if (get_irn_op(a) == op_Conv &&
- get_irn_mode (get_Conv_op(a)) == mode_b) {
- n = get_Conv_op(a); /* Convb(Conv*(xxxb(...))) == xxxb(...) */
- }
- }
- break;
+ new_and = new_r_And(current_ir_graph, block,
+ value, new_r_Const(current_ir_graph, block, mode, tarval_and(tv4, tv2)), mode);
- case iro_Phi:
- {
- /* Several optimizations:
- - no Phi in start block.
- - remove Id operators that are inputs to Phi
- - fold Phi-nodes, iff they have only one predecessor except
- themselves.
- */
- int i, n_preds;
+ new_const = new_r_Const(current_ir_graph, block, mode, tarval_or(tv3, tv1));
+ set_Or_left(or, new_and);
+ set_Or_right(or, new_const);
- ir_node *block = NULL; /* to shutup gcc */
- ir_node *first_val = NULL; /* to shutup gcc */
- ir_node *scnd_val = NULL; /* to shutup gcc */
+ /* check for more */
+ return transform_node_Or(or);
+}
- n_preds = get_Phi_n_preds(n);
+/**
+ * Tries several [inplace] [optimizing] transformations and returns an
+ * equivalent node. The difference to equivalent_node() is that these
+ * transformations _do_ generate new nodes, and thus the old node must
+ * not be freed even if the equivalent node isn't the old one.
+ */
+static ir_node *transform_node(ir_node *n)
+{
+ if (n->op->transform_node)
+ n = n->op->transform_node(n);
+ return n;
+}
- block = get_nodes_Block(n);
- assert(get_irn_op (block) == op_Block);
+/**
+ * set the default transform node operation
+ */
+static ir_op *firm_set_default_transform_node(ir_op *op)
+{
+#define CASE(a) \
+ case iro_##a: \
+ op->transform_node = transform_node_##a; \
+ break
+
+ switch (op->code) {
+ CASE(Mul);
+ CASE(Div);
+ CASE(Mod);
+ CASE(DivMod);
+ CASE(Cond);
+ CASE(Eor);
+ CASE(Not);
+ CASE(Proj);
+ CASE(Or);
+ default:
+ op->transform_node = NULL;
+ }
- /* there should be no Phi nodes in the Start region. */
- if (block == current_ir_graph->start_block) {
- n = new_Bad();
- break;
- }
+ return op;
+#undef CASE
+}
- if (n_preds == 0) { /* Phi of dead Region without predecessors. */
- /* GL: why not return new_Bad? */
- break;
- }
-#if 0
- /* first we test for a special case: */
- /* Confirm is a special node fixing additional information for a
- value that is known at a certain point. This is useful for
- dataflow analysis. */
- if (n_preds == 2) {
- ir_node *a = follow_Id (get_Phi_pred(n, 0));
- ir_node *b = follow_Id (get_Phi_pred(n, 1));
- if ( (get_irn_op(a) == op_Confirm)
- && (get_irn_op(b) == op_Confirm)
- && (follow_Id (get_irn_n(a, 0)) == follow_Id(get_irn_n(b, 0)))
- && (get_irn_n(a, 1) == get_irn_n (b, 1))
- && (a->data.num == (~b->data.num & irpn_True) )) {
- n = follow_Id (get_irn_n(a, 0));
- break;
- }
- }
-#endif
+/* **************** Common Subexpression Elimination **************** */
- /* Find first non-self-referencing input */
- for (i = 0; i < n_preds; ++i) {
- first_val = follow_Id(get_Phi_pred(n, i));
- /* skip Id's */
- set_Phi_pred(n, i, first_val);
- if ( (first_val != n) /* not self pointer */
- && (get_irn_op(first_val) != op_Bad) /* value not dead */
- && !(is_Bad (get_Block_cfgpred(block, i))) ) { /* not dead control flow */
- break; /* then found first value. */
- }
- }
+/** The size of the hash table used, should estimate the number of nodes
+ in a graph. */
+#define N_IR_NODES 512
- /* A totally Bad or self-referencing Phi (we didn't break the above loop) */
- if (i >= n_preds) { n = new_Bad(); break; }
-
- scnd_val = NULL;
-
- /* follow_Id () for rest of inputs, determine if any of these
- are non-self-referencing */
- while (++i < n_preds) {
- scnd_val = follow_Id(get_Phi_pred(n, i));
- /* skip Id's */
- set_Phi_pred(n, i, scnd_val);
- if ( (scnd_val != n)
- && (scnd_val != first_val)
- && (get_irn_op(scnd_val) != op_Bad)
- && !(is_Bad (get_Block_cfgpred(block, i))) ) {
- break;
- }
- }
+/** Compares the attributes of two Const nodes. */
+static int node_cmp_attr_Const(ir_node *a, ir_node *b)
+{
+ return (get_Const_tarval(a) != get_Const_tarval(b))
+ || (get_Const_type(a) != get_Const_type(b));
+}
- /* Fold, if no multiple distinct non-self-referencing inputs */
- if (i >= n_preds) {
- n = first_val;
- } else {
- /* skip the remaining Ids. */
- while (++i < n_preds) {
- set_Phi_pred(n, i, follow_Id(get_Phi_pred(n, i)));
- }
- }
- }
- break;
+/** Compares the attributes of two Proj nodes. */
+static int node_cmp_attr_Proj(ir_node *a, ir_node *b)
+{
+ return get_irn_proj_attr (a) != get_irn_proj_attr (b);
+}
- case iro_Load:
- {
- a = skip_Proj(get_Load_mem(n));
- b = skip_Proj(get_Load_ptr(n));
-
- if (get_irn_op(a) == op_Store) {
- if ( different_identity (b, get_Store_ptr(a))) {
- /* load and store use different pointers, therefore load
- needs not take store's memory but the state before. */
- set_Load_mem (n, get_Store_mem(a));
- } else if (( 0 /* ???didn't get cryptic test that returns 0 */ )) {
- }
- }
- }
- break;
- case iro_Store:
- /* remove unnecessary store. */
- {
- a = skip_Proj(get_Store_mem(n));
- b = get_Store_ptr(n);
- c = skip_Proj(get_Store_value(n));
-
- if (get_irn_op(a) == op_Store
- && get_Store_ptr(a) == b
- && skip_Proj(get_Store_value(a)) == c) {
- /* We have twice exactly the same store -- a write after write. */
- n = a;
- } else if (get_irn_op(c) == op_Load
- && (a == c || skip_Proj(get_Load_mem(c)) == a)
- && get_Load_ptr(c) == b )
- /* !!!??? and a cryptic test */ {
- /* We just loaded the value from the same memory, i.e., the store
- doesn't change the memory -- a write after read. */
- turn_into_tuple(n, 2);
- set_Tuple_pred(n, 0, a);
- set_Tuple_pred(n, 1, new_Bad());
- }
- }
- break;
+/** Compares the attributes of two Filter nodes. */
+static int node_cmp_attr_Filter(ir_node *a, ir_node *b)
+{
+ return get_Filter_proj(a) != get_Filter_proj(b);
+}
- case iro_Proj:
- {
- a = get_Proj_pred(n);
-
- if ( get_irn_op(a) == op_Tuple) {
- /* Remove the Tuple/Proj combination. */
- if ( get_Proj_proj(n) <= get_Tuple_n_preds(a) ) {
- n = get_Tuple_pred(a, get_Proj_proj(n));
- } else {
- assert(0); /* This should not happen! (GL added this assert) */
- n = new_Bad();
- }
- } else if (get_irn_mode(n) == mode_X &&
- is_Bad(get_nodes_Block(n))) {
- /* Remove dead control flow. */
- n = new_Bad();
- }
- }
- break;
+/** Compares the attributes of two Alloc nodes. */
+static int node_cmp_attr_Alloc(ir_node *a, ir_node *b)
+{
+ return (get_irn_alloc_attr(a).where != get_irn_alloc_attr(b).where)
+ || (get_irn_alloc_attr(a).type != get_irn_alloc_attr(b).type);
+}
- case iro_Id:
- n = follow_Id (n);
- break;
+/** Compares the attributes of two Free nodes. */
+static int node_cmp_attr_Free(ir_node *a, ir_node *b)
+{
+ return (get_irn_free_attr(a) != get_irn_free_attr(b));
+}
- default: break;
- }
+/** Compares the attributes of two SymConst nodes. */
+static int node_cmp_attr_SymConst(ir_node *a, ir_node *b)
+{
+ return (get_irn_symconst_attr(a).num != get_irn_symconst_attr(b).num)
+ || (get_irn_symconst_attr(a).sym.type_p != get_irn_symconst_attr(b).sym.type_p);
+}
- return n;
-} /* end equivalent_node() */
+/** Compares the attributes of two Call nodes. */
+static int node_cmp_attr_Call(ir_node *a, ir_node *b)
+{
+ return (get_irn_call_attr(a) != get_irn_call_attr(b));
+}
+/** Compares the attributes of two FuncCall nodes. */
+static int node_cmp_attr_FuncCall(ir_node *a, ir_node *b)
+{
+ return (get_irn_funccall_attr(a) != get_irn_funccall_attr(b));
+}
-/* tries several [inplace] [optimizing] transformations and returns a
- equivalent node. The difference to equivalent_node is that these
- transformations _do_ generate new nodes, and thus the old node must
- not be freed even if the equivalent node isn't the old one. */
-static ir_node *
-transform_node (ir_node *n)
+/** Compares the attributes of two Sel nodes. */
+static int node_cmp_attr_Sel(ir_node *a, ir_node *b)
{
+ return (get_irn_sel_attr(a).ent->kind != get_irn_sel_attr(b).ent->kind)
+ || (get_irn_sel_attr(a).ent->name != get_irn_sel_attr(b).ent->name)
+ || (get_irn_sel_attr(a).ent->owner != get_irn_sel_attr(b).ent->owner)
+ || (get_irn_sel_attr(a).ent->ld_name != get_irn_sel_attr(b).ent->ld_name)
+ || (get_irn_sel_attr(a).ent->type != get_irn_sel_attr(b).ent->type);
+}
- ir_node *a = NULL, *b;
- tarval *ta, *tb;
+/** Compares the attributes of two Phi nodes. */
+static int node_cmp_attr_Phi(ir_node *a, ir_node *b)
+{
+ return get_irn_phi_attr (a) != get_irn_phi_attr (b);
+}
- switch (get_irn_opcode(n)) {
- case iro_DivMod: {
+/** Compares the attributes of two Cast nodes. */
+static int node_cmp_attr_Cast(ir_node *a, ir_node *b)
+{
+ return get_Cast_type(a) != get_Cast_type(b);
+}
- int evaluated = 0;
- ir_mode *mode;
+/** Compares the attributes of two Load nodes. */
+static int node_cmp_attr_Load(ir_node *a, ir_node *b)
+{
+ if (get_Load_volatility(a) == volatility_is_volatile ||
+ get_Load_volatility(b) == volatility_is_volatile)
+ /* NEVER do CSE on volatile Loads */
+ return 1;
- a = get_DivMod_left(n);
- b = get_DivMod_right(n);
- mode = get_irn_mode(a);
+ return get_Load_mode(a) != get_Load_mode(b);
+}
- if (!( mode_is_int(get_irn_mode(a))
- && mode_is_int(get_irn_mode(b))))
- break;
+/** Compares the attributes of two Store nodes. */
+static int node_cmp_attr_Store(ir_node *a, ir_node *b)
+{
+ /* NEVER do CSE on volatile Stores */
+ return (get_Store_volatility(a) == volatility_is_volatile ||
+ get_Load_volatility(b) == volatility_is_volatile);
+}
- if (a == b) {
- a = new_Const (mode, tarval_from_long (mode, 1));
- b = new_Const (mode, tarval_from_long (mode, 0));
- evaluated = 1;
- } else {
- ta = value_of(a);
- tb = value_of(b);
-
- if (tb) {
- if (tarval_classify(tb) == 1) {
- b = new_Const (mode, tarval_from_long (mode, 0));
- evaluated = 1;
- } else if (ta) {
- tarval *resa, *resb;
- resa = tarval_div (ta, tb);
- if (!resa) break; /* Causes exception!!! Model by replacing through
- Jmp for X result!? */
- resb = tarval_mod (ta, tb);
- if (!resb) break; /* Causes exception! */
- a = new_Const (mode, resa);
- b = new_Const (mode, resb);
- evaluated = 1;
- }
- } else if (tarval_classify (ta) == 0) {
- b = a;
- evaluated = 1;
- }
- }
- if (evaluated) { /* replace by tuple */
- ir_node *mem = get_DivMod_mem(n);
- turn_into_tuple(n, 4);
- set_Tuple_pred(n, 0, mem);
- set_Tuple_pred(n, 1, new_Bad()); /* no exception */
- set_Tuple_pred(n, 2, a);
- set_Tuple_pred(n, 3, b);
- assert(get_nodes_Block(n));
- }
- }
- break;
-
- case iro_Cond: {
- /* Replace the Cond by a Jmp if it branches on a constant
- condition. */
- ir_node *jmp;
- a = get_Cond_selector(n);
- ta = value_of(a);
-
- if (ta && (get_irn_mode(a) == mode_b)) {
- /* It's a boolean Cond, branching on a boolean constant.
- Replace it by a tuple (Bad, Jmp) or (Jmp, Bad) */
- jmp = new_r_Jmp(current_ir_graph, get_nodes_Block(n));
- turn_into_tuple(n, 2);
- if (tv_val_b(ta) == 1) /* GL: I hope this returns 1 if true */ {
- set_Tuple_pred(n, 0, new_Bad());
- set_Tuple_pred(n, 1, jmp);
- } else {
- set_Tuple_pred(n, 0, jmp);
- set_Tuple_pred(n, 1, new_Bad());
- }
- } else if (ta && (get_irn_mode(a) == mode_I) && (get_Cond_kind(n) == dense)) {
- /* I don't want to allow Tuples smaller than the biggest Proj.
- Also this tuple might get really big...
- I generate the Jmp here, and remember it in link. Link is used
- when optimizing Proj. */
- set_irn_link(n, new_r_Jmp(current_ir_graph, get_nodes_Block(n)));
- } else if ( (get_irn_op(get_Cond_selector(n)) == op_Eor)
- && (get_irn_mode(get_Cond_selector(n)) == mode_b)
- && (tarval_classify(computed_value(get_Eor_right(a))) == 1)) {
- /* The Eor is a negate. Generate a new Cond without the negate,
- simulate the negate by exchanging the results. */
- set_irn_link(n, new_r_Cond(current_ir_graph, get_nodes_Block(n),
- get_Eor_left(a)));
- } else if ( (get_irn_op(get_Cond_selector(n)) == op_Not)
- && (get_irn_mode(get_Cond_selector(n)) == mode_b)) {
- /* A Not before the Cond. Generate a new Cond without the Not,
- simulate the Not by exchanging the results. */
- set_irn_link(n, new_r_Cond(current_ir_graph, get_nodes_Block(n),
- get_Not_op(a)));
- }
- }
- break;
-
- case iro_Proj: {
- a = get_Proj_pred(n);
-
- if ( (get_irn_op(a) == op_Cond)
- && get_irn_link(a)
- && get_irn_op(get_irn_link(a)) == op_Cond) {
- /* Use the better Cond if the Proj projs from a Cond which get's
- its result from an Eor/Not. */
- assert ( ( (get_irn_op(get_Cond_selector(a)) == op_Eor)
- || (get_irn_op(get_Cond_selector(a)) == op_Not))
- && (get_irn_mode(get_Cond_selector(a)) == mode_b)
- && (get_irn_op(get_irn_link(a)) == op_Cond)
- && (get_Cond_selector(get_irn_link(a)) ==
- get_Eor_left(get_Cond_selector(a))));
- set_Proj_pred(n, get_irn_link(a));
- if (get_Proj_proj(n) == 0)
- set_Proj_proj(n, 1);
- else
- set_Proj_proj(n, 0);
- } else if ( (get_irn_op(a) == op_Cond)
- && (get_irn_mode(get_Cond_selector(a)) == mode_I)
- && value_of(a)
- && (get_Cond_kind(a) == dense)) {
- /* The Cond is a Switch on a Constant */
- if (get_Proj_proj(n) == tv_val_CHIL(value_of(a))) {
- /* The always taken branch, reuse the existing Jmp. */
- if (!get_irn_link(a)) /* well, if it exists ;-> */
- set_irn_link(a, new_r_Jmp(current_ir_graph, get_nodes_Block(n)));
- assert(get_irn_op(get_irn_link(a)) == op_Jmp);
- n = get_irn_link(a);
- } else {/* Not taken control flow, but be careful with the default! */
- if (get_Proj_proj(n) < a->attr.c.default_proj){
- /* a never taken branch */
- n = new_Bad();
- } else {
- a->attr.c.default_proj = get_Proj_proj(n);
- }
- }
- }
- } break;
- case iro_Eor: { /* @@@ not tested as boolean Eor not allowed any more. */
- a = get_Eor_left(n);
- b = get_Eor_right(n);
-
- if ( (get_irn_mode(n) == mode_b)
- && (get_irn_op(a) == op_Proj)
- && (get_irn_mode(a) == mode_b)
- && (tarval_classify (computed_value (b)) == 1)
- && (get_irn_op(get_Proj_pred(a)) == op_Cmp))
- /* The Eor negates a Cmp. The Cmp has the negated result anyways! */
- n = new_r_Proj(current_ir_graph, get_nodes_Block(n), get_Proj_pred(a),
- mode_b, get_negated_pnc(get_Proj_proj(a)));
- else if ( (get_irn_mode(n) == mode_b)
- && (tarval_classify (computed_value (b)) == 1))
- /* The Eor is a Not. Replace it by a Not. */
- /* ????!!!Extend to bitfield 1111111. */
- n = new_r_Not(current_ir_graph, get_nodes_Block(n), a, mode_b);
- }
- break;
- case iro_Not: {
- a = get_Not_op(n);
-
- if ( (get_irn_mode(n) == mode_b)
- && (get_irn_op(a) == op_Proj)
- && (get_irn_mode(a) == mode_b)
- && (get_irn_op(get_Proj_pred(a)) == op_Cmp))
- /* We negate a Cmp. The Cmp has the negated result anyways! */
- n = new_r_Proj(current_ir_graph, get_nodes_Block(n), get_Proj_pred(a),
- mode_b, get_negated_pnc(get_Proj_proj(a)));
- }
- break;
- default: ;
+/**
+ * set the default node attribute compare operation
+ */
+static ir_op *firm_set_default_node_cmp_attr(ir_op *op)
+{
+#define CASE(a) \
+ case iro_##a: \
+ op->node_cmp_attr = node_cmp_attr_##a; \
+ break
+
+ switch (op->code) {
+ CASE(Const);
+ CASE(Proj);
+ CASE(Filter);
+ CASE(Alloc);
+ CASE(Free);
+ CASE(SymConst);
+ CASE(Call);
+ CASE(FuncCall);
+ CASE(Sel);
+ CASE(Phi);
+ CASE(Cast);
+ CASE(Load);
+ CASE(Store);
+ default:
+ op->node_cmp_attr = NULL;
}
- return n;
-}
-/* **************** Common Subexpression Elimination **************** */
+ return op;
+#undef CASE
+}
-/* Compare function for two nodes in the hash table. Gets two */
-/* nodes as parameters. */
-/* @@@ a+b != b+a ? */
+/**
+ * Compare function for two nodes in the hash table. Gets two
+ * nodes as parameters. Returns 0 if the nodes are a cse.
+ */
static int
vt_cmp (const void *elt, const void *key)
{
ir_node *a, *b;
- int i;
+ int i, irn_arity_a;
a = (void *)elt;
b = (void *)key;
(get_irn_mode(a) != get_irn_mode(b))) return 1;
/* compare if a's in and b's in are equal */
- /* GL: we optimize only nodes with in arrays of fixed sizes.
- if (get_irn_arity (a) != -2) {
- ins = get_irn_arity (a);
- if (ins != get_irn_arity (b)) return 1;
- ain = get_irn_in (a);
- bin = get_irn_in (b);
- }
- */
- if (get_irn_arity (a) != get_irn_arity(b))
+ irn_arity_a = get_irn_arity (a);
+ if (irn_arity_a != get_irn_arity(b))
return 1;
- /* compare a->in[0..ins] with b->in[0..ins], i.e., include the block. */
- /* do if (*ain++ != *bin++) return 1; while (ins--); */
- for (i = -1; i < get_irn_arity(a); i++)
- if (get_irn_n(a, i) != get_irn_n(b, i))
+ /* for block-local cse and op_pin_state_pinned nodes: */
+ if (!get_opt_global_cse() || (get_irn_pinned(a) == op_pin_state_pinned)) {
+ if (get_irn_n(a, -1) != get_irn_n(b, -1))
return 1;
+ }
+ /* compare a->in[0..ins] with b->in[0..ins] */
+ for (i = 0; i < irn_arity_a; i++)
+ if (get_irn_n(a, i) != get_irn_n(b, i))
+ return 1;
- switch (get_irn_opcode(a)) {
- case iro_Const:
- return get_irn_const_attr (a) != get_irn_const_attr (b);
- case iro_Proj:
- return get_irn_proj_attr (a) != get_irn_proj_attr (b);
- case iro_Alloc:
- return (get_irn_alloc_attr(a).where != get_irn_alloc_attr(b).where)
- || (get_irn_alloc_attr(a).type != get_irn_alloc_attr(b).type);
- case iro_Free:
- return (get_irn_free_attr(a) != get_irn_free_attr(b));
- case iro_SymConst:
- return (get_irn_symconst_attr(a).num != get_irn_symconst_attr(b).num)
- || (get_irn_symconst_attr(a).tori.typ != get_irn_symconst_attr(b).tori.typ);
- case iro_Call:
- return (get_irn_call_attr(a) != get_irn_call_attr(b));
- case iro_Sel:
- return (get_irn_sel_attr(a).ent->kind != get_irn_sel_attr(b).ent->kind)
- || (get_irn_sel_attr(a).ent->name != get_irn_sel_attr(b).ent->name)
- || (get_irn_sel_attr(a).ent->owner != get_irn_sel_attr(b).ent->owner)
- || (get_irn_sel_attr(a).ent->ld_name != get_irn_sel_attr(b).ent->ld_name)
- || (get_irn_sel_attr(a).ent->type != get_irn_sel_attr(b).ent->type)
- || (get_irn_sel_attr(a).ltyp != get_irn_sel_attr(b).ltyp);
- case iro_Phi:
- return get_irn_phi_attr (a) != get_irn_phi_attr (b);
- default: ;
- }
+ /*
+ * here, we already now that the nodes are identical except their
+ * attributes
+ */
+ if (a->op->node_cmp_attr)
+ return a->op->node_cmp_attr(a, b);
return 0;
}
-static unsigned
+/*
+ * Calculate a hash value of a node.
+ */
+unsigned
ir_node_hash (ir_node *node)
{
unsigned h;
- int i;
-
- /* hash table value = 9*(9*(9*(9*(9*arity+in[0])+in[1])+ ...)+mode)+code */
- h = get_irn_arity(node);
+ int i, irn_arity;
+
+ if (node->op == op_Const) {
+ /* special value for const, as they only differ in their tarval. */
+ h = ((unsigned) node->attr.con.tv)>>3 ;
+ h = 9*h + (unsigned)get_irn_mode(node);
+ } else if (node->op == op_SymConst) {
+ /* special value for const, as they only differ in their symbol. */
+ h = ((unsigned) node->attr.i.sym.type_p)>>3 ;
+ h = 9*h + (unsigned)get_irn_mode(node);
+ } else {
+
+ /* hash table value = 9*(9*(9*(9*(9*arity+in[0])+in[1])+ ...)+mode)+code */
+ h = irn_arity = get_irn_arity(node);
+
+ /* consider all in nodes... except the block. */
+ for (i = 0; i < irn_arity; i++) {
+ h = 9*h + (unsigned)get_irn_n(node, i);
+ }
- /* consider all in nodes... except the block. */
- for (i = 0; i < get_irn_arity(node); i++) {
- h = 9*h + (unsigned long)get_irn_n(node, i);
+ /* ...mode,... */
+ h = 9*h + (unsigned) get_irn_mode (node);
+ /* ...and code */
+ h = 9*h + (unsigned) get_irn_op (node);
}
- /* ...mode,... */
- h = 9*h + (unsigned long) get_irn_mode (node);
- /* ...and code */
- h = 9*h + (unsigned long) get_irn_op (node);
-
return h;
}
pset *
new_identities (void)
{
- return new_pset (vt_cmp, TUNE_NIR_NODES);
+ return new_pset (vt_cmp, N_IR_NODES);
}
void
del_pset (value_table);
}
-void
-add_identities (pset *value_table, ir_node *node) {
- identify_remember (value_table, node);
-}
-
-/* Return the canonical node computing the same value as n.
- Looks up the node in a hash table. */
-static inline ir_node *
+/**
+ * Return the canonical node computing the same value as n.
+ * Looks up the node in a hash table.
+ *
+ * For Const nodes this is performed in the constructor, too. Const
+ * nodes are extremely time critical because of their frequent use in
+ * constant string arrays.
+ */
+static INLINE ir_node *
identify (pset *value_table, ir_node *n)
{
ir_node *o = NULL;
if (!value_table) return n;
- switch (get_irn_opcode (n)) {
- case iro_Add:
- case iro_Mul:
- case iro_Or:
- case iro_And:
- case iro_Eor:
- {
+ if (get_opt_reassociation()) {
+ if (is_op_commutative(get_irn_op(n))) {
+ ir_node *l = get_binop_left(n);
+ ir_node *r = get_binop_right(n);
+
/* for commutative operators perform a OP b == b OP a */
- if (get_binop_left(n) > get_binop_right(n)) {
- ir_node *h = get_binop_left(n);
- set_binop_left(n, get_binop_right(n));
- set_binop_right(n, h);
+ if (l > r) {
+ set_binop_left(n, r);
+ set_binop_right(n, l);
}
}
- break;
- default: break;
}
+
o = pset_find (value_table, n, ir_node_hash (n));
if (!o) return n;
+ DBG_OPT_CSE(n, o);
+
return o;
}
-/* Return the canonical node computing the same value as n.
- Looks up the node in a hash table, enters it in the table
- if it isn't there yet. */
+/**
+ * During construction we set the op_pin_state_pinned flag in the graph right when the
+ * optimization is performed. The flag turning on procedure global cse could
+ * be changed between two allocations. This way we are safe.
+ */
+static INLINE ir_node *
+identify_cons (pset *value_table, ir_node *n) {
+ ir_node *old = n;
+
+ n = identify(value_table, n);
+ if (get_irn_n(old, -1) != get_irn_n(n, -1))
+ set_irg_pinned(current_ir_graph, op_pin_state_floats);
+ return n;
+}
+
+/**
+ * Return the canonical node computing the same value as n.
+ * Looks up the node in a hash table, enters it in the table
+ * if it isn't there yet.
+ */
static ir_node *
-identify_remember (pset *value_table, ir_node *node)
+identify_remember (pset *value_table, ir_node *n)
{
ir_node *o = NULL;
- if (!value_table) return node;
+ if (!value_table) return n;
+
+ if (get_opt_reassociation()) {
+ if (is_op_commutative(get_irn_op(n))) {
+ ir_node *l = get_binop_left(n);
+ ir_node *r = get_binop_right(n);
+
+ /* for commutative operators perform a OP b == b OP a */
+ if (l > r) {
+ set_binop_left(n, r);
+ set_binop_right(n, l);
+ }
+ }
+ }
/* lookup or insert in hash table with given hash key. */
- o = pset_insert (value_table, node, ir_node_hash (node));
+ o = pset_insert (value_table, n, ir_node_hash (n));
- if (o == node) return node;
+ if (o != n) {
+ DBG_OPT_CSE(n, o);
+ }
return o;
}
-/* garbage in, garbage out. If a node has a dead input, i.e., the
- Bad node is input to the node, return the Bad node. */
-static inline ir_node *
+void
+add_identities (pset *value_table, ir_node *node) {
+ if (get_opt_cse() && (get_irn_opcode(node) != iro_Block))
+ identify_remember (value_table, node);
+}
+
+/**
+ * garbage in, garbage out. If a node has a dead input, i.e., the
+ * Bad node is input to the node, return the Bad node.
+ */
+static INLINE ir_node *
gigo (ir_node *node)
{
- int i;
+ int i, irn_arity;
ir_op* op = get_irn_op(node);
+ /* remove garbage blocks by looking at control flow that leaves the block
+ and replacing the control flow by Bad. */
+ if (get_irn_mode(node) == mode_X) {
+ ir_node *block = get_nodes_block(node);
+ if (op == op_End) return node; /* Don't optimize End, may have Bads. */
+ if (get_irn_op(block) == op_Block && get_Block_matured(block)) {
+ irn_arity = get_irn_arity(block);
+ for (i = 0; i < irn_arity; i++) {
+ if (!is_Bad(get_irn_n(block, i))) break;
+ }
+ if (i == irn_arity) return new_Bad();
+ }
+ }
+
/* Blocks, Phis and Tuples may have dead inputs, e.g., if one of the
blocks predecessors is dead. */
if ( op != op_Block && op != op_Phi && op != op_Tuple) {
- for (i = -1; i < get_irn_arity(node); i++) {
+ irn_arity = get_irn_arity(node);
+ for (i = -1; i < irn_arity; i++) {
if (is_Bad(get_irn_n(node, i))) {
return new_Bad();
}
}
}
#if 0
+ /* With this code we violate the agreement that local_optimize
+ only leaves Bads in Block, Phi and Tuple nodes. */
/* If Block has only Bads as predecessors it's garbage. */
/* If Phi has only Bads as predecessors it's garbage. */
- if (op == op_Block || op == op_Phi) {
- for (i = 0; i < get_irn_arity(node); i++) {
+ if ((op == op_Block && get_Block_matured(node)) || op == op_Phi) {
+ irn_arity = get_irn_arity(node);
+ for (i = 0; i < irn_arity; i++) {
if (!is_Bad(get_irn_n(node, i))) break;
}
- if (i = get_irn_arity(node)) node = new_Bad();
+ if (i == irn_arity) node = new_Bad();
}
#endif
return node;
}
-/* These optimizations deallocate nodes from the obstack.
- It can only be called if it is guaranteed that no other nodes
- reference this one, i.e., right after construction of a node. */
+/**
+ * These optimizations deallocate nodes from the obstack.
+ * It can only be called if it is guaranteed that no other nodes
+ * reference this one, i.e., right after construction of a node.
+ */
ir_node *
-optimize (ir_node *n)
+optimize_node (ir_node *n)
{
tarval *tv;
- ir_node *old_n = n;
+ ir_node *oldn = n;
+ opcode iro = get_irn_opcode(n);
- /* Allways optimize Phi nodes: part of the construction. */
- if ((!get_optimize()) && (get_irn_op(n) != op_Phi)) return n;
-
- /* if not optimize return n */
- if (n == NULL) {
- printf(" attention: empty node!!! \n");
- return n;
- }
+ /* Always optimize Phi nodes: part of the construction. */
+ if ((!get_opt_optimize()) && (iro != iro_Phi)) return n;
/* constant expression evaluation / constant folding */
if (get_opt_constant_folding()) {
/* constants can not be evaluated */
- if (get_irn_op(n) != op_Const) {
+ if (iro != iro_Const) {
/* try to evaluate */
tv = computed_value (n);
- if (tv != NULL) {
- /* evaluation was succesful -- replace the node. */
- obstack_free (current_ir_graph->obst, n);
- return new_Const (get_tv_mode (tv), tv);
+ if ((get_irn_mode(n) != mode_T) && (tv != tarval_bad)) {
+ /*
+ * we MUST copy the node here temporary, because it's still needed
+ * for DBG_OPT_ALGSIM0
+ */
+ int node_size = offsetof(ir_node, attr) + n->op->attr_size;
+ oldn = alloca(node_size);
+
+ memcpy(oldn, n, node_size);
+ CLONE_ARR_A(ir_node *, oldn->in, n->in);
+
+ /* ARG, copy the in array, we need it for statistics */
+ memcpy(oldn->in, n->in, ARR_LEN(n->in) * sizeof(n->in[0]));
+
+ /* evaluation was successful -- replace the node. */
+ obstack_free (current_ir_graph->obst, n);
+ n = new_Const (get_tarval_mode (tv), tv);
+
+ DBG_OPT_ALGSIM0(oldn, n);
+ return n;
}
}
}
/* remove unnecessary nodes */
- if (get_opt_constant_folding() || get_irn_op(n) == op_Phi)
+ if (get_opt_constant_folding() ||
+ (iro == iro_Phi) || /* always optimize these nodes. */
+ (iro == iro_Id) ||
+ (iro == iro_Proj) ||
+ (iro == iro_Block) ) /* Flags tested local. */
n = equivalent_node (n);
+ optimize_preds(n); /* do node specific optimizations of nodes predecessors. */
+
/** common subexpression elimination **/
/* Checks whether n is already available. */
/* The block input is used to distinguish different subexpressions. Right
- now all nodes are pinned to blocks, i.e., the cse only finds common
+ now all nodes are op_pin_state_pinned to blocks, i.e., the cse only finds common
subexpressions within a block. */
if (get_opt_cse())
- n = identify (current_ir_graph->value_table, n);
- /* identify found a cse, so deallocate the old node. */
- if (n != old_n) {
- obstack_free (current_ir_graph->obst, old_n);
- /* The AmRoq fiasco returns n here. Martin's version doesn't. */
+ n = identify_cons (current_ir_graph->value_table, n);
+
+ if (n != oldn) {
+ /* We found an existing, better node, so we can deallocate the old node. */
+ obstack_free (current_ir_graph->obst, oldn);
+
+ return n;
}
/* Some more constant expression evaluation that does not allow to
free the node. */
- if (get_opt_constant_folding())
+ iro = get_irn_opcode(n);
+ if (get_opt_constant_folding() ||
+ (iro == iro_Cond) ||
+ (iro == iro_Proj)) /* Flags tested local. */
n = transform_node (n);
- /* Remove nodes with dead (Bad) input. */
+ /* Remove nodes with dead (Bad) input.
+ Run always for transformation induced Bads. */
n = gigo (n);
- /* Now we can verify the node, as it has no dead inputs any more. */
- irn_vrfy(n);
/* Now we have a legal, useful node. Enter it in hash table for cse */
- if (get_opt_cse()) {
+ if (get_opt_cse() && (get_irn_opcode(n) != iro_Block)) {
n = identify_remember (current_ir_graph->value_table, n);
}
-#if 0 /* GL: what's the use of this?? */
- if ((current_ir_graph->state & irgs_building) && IR_KEEP_ALIVE (n)) {
- assert (~current_ir_graph->state & irgs_keep_alives_in_arr);
- pdeq_putr (current_ir_graph->keep.living, n);
- }
-#endif
return n;
}
-/* These optimizations never deallocate nodes. This can cause dead
- nodes lying on the obstack. Remove these by a dead node elimination,
- i.e., a copying garbage collection. */
+/**
+ * These optimizations never deallocate nodes. This can cause dead
+ * nodes lying on the obstack. Remove these by a dead node elimination,
+ * i.e., a copying garbage collection.
+ */
ir_node *
-optimize_in_place (ir_node *n)
+optimize_in_place_2 (ir_node *n)
{
tarval *tv;
- ir_node *old_n = n;
+ ir_node *oldn = n;
+ opcode iro = get_irn_opcode(n);
- if (!get_optimize()) return n;
+ if (!get_opt_optimize() && (get_irn_op(n) != op_Phi)) return n;
/* if not optimize return n */
if (n == NULL) {
+ assert(0);
/* Here this is possible. Why? */
return n;
}
+
/* constant expression evaluation / constant folding */
if (get_opt_constant_folding()) {
/* constants can not be evaluated */
- if (get_irn_op(n) != op_Const) {
+ if (iro != iro_Const) {
/* try to evaluate */
tv = computed_value (n);
- if (tv != NULL) {
- /* evaluation was succesful -- replace the node. */
- n = new_Const (get_tv_mode (tv), tv);
- deb_info_copy(n, old_n, id_from_str("const_eval", 10));
- return n;
- /* xprintf("* optimize: computed node %I\n", n->op->name);*/
+ if ((get_irn_mode(n) != mode_T) && (tv != tarval_bad)) {
+ /* evaluation was successful -- replace the node. */
+ n = new_Const (get_tarval_mode (tv), tv);
+
+ DBG_OPT_ALGSIM0(oldn, n);
+ return n;
}
}
}
/* remove unnecessary nodes */
- /*if (get_opt_constant_folding()) */
- if (get_opt_constant_folding() || get_irn_op(n) == op_Phi)
+ if (get_opt_constant_folding() ||
+ (iro == iro_Phi) || /* always optimize these nodes. */
+ (iro == iro_Id) || /* ... */
+ (iro == iro_Proj) || /* ... */
+ (iro == iro_Block) ) /* Flags tested local. */
n = equivalent_node (n);
+ optimize_preds(n); /* do node specific optimizations of nodes predecessors. */
+
/** common subexpression elimination **/
/* Checks whether n is already available. */
/* The block input is used to distinguish different subexpressions. Right
- now all nodes are pinned to blocks, i.e., the cse only finds common
+ now all nodes are op_pin_state_pinned to blocks, i.e., the cse only finds common
subexpressions within a block. */
- if (get_opt_cse())
+ if (get_opt_cse()) {
n = identify (current_ir_graph->value_table, n);
-
- /* identify found a cse, so deallocate the old node. */
- if (n != old_n) {
- /* The AmRoq fiasco returns n here. Martin's version doesn't. */
}
/* Some more constant expression evaluation. */
- if (get_opt_constant_folding())
+ iro = get_irn_opcode(n);
+ if (get_opt_constant_folding() ||
+ (iro == iro_Cond) ||
+ (iro == iro_Proj)) /* Flags tested local. */
n = transform_node (n);
- /* Remove nodes with dead (Bad) input. */
+ /* Remove nodes with dead (Bad) input.
+ Run always for transformation induced Bads. */
n = gigo (n);
+
/* Now we can verify the node, as it has no dead inputs any more. */
irn_vrfy(n);
return n;
}
+
+/**
+ * Wrapper for external use, set proper status bits after optimization.
+ */
+ir_node *
+optimize_in_place (ir_node *n)
+{
+ /* Handle graph state */
+ assert(get_irg_phase_state(current_ir_graph) != phase_building);
+
+ if (get_opt_global_cse())
+ set_irg_pinned(current_ir_graph, op_pin_state_floats);
+ if (get_irg_outs_state(current_ir_graph) == outs_consistent)
+ set_irg_outs_inconsistent(current_ir_graph);
+
+ /* Maybe we could also test whether optimizing the node can
+ change the control graph. */
+ if (get_irg_dom_state(current_ir_graph) == dom_consistent)
+ set_irg_dom_inconsistent(current_ir_graph);
+ return optimize_in_place_2 (n);
+}
+
+/**
+ * set the default ir op operations
+ */
+ir_op *firm_set_default_operations(ir_op *op)
+{
+ op = firm_set_default_computed_value(op);
+ op = firm_set_default_equivalent_node(op);
+ op = firm_set_default_transform_node(op);
+ op = firm_set_default_node_cmp_attr(op);
+
+ return op;
+}