slight bugfix

[libfirm] / ir / be / bespill.c

diff --git a/ir/be/bespill.c b/ir/be/bespill.c
index 3c63fd9..2656953 100644 (file)
--- a/ir/be/bespill.c
+++ b/ir/be/bespill.c
@@ -14,6 +14,7 @@
 #include "irnode_t.h"
 #include "ircons_t.h"
 #include "iredges_t.h"
+#include "irprintf.h"
 #include "ident_t.h"
 #include "type_t.h"
 #include "entity_t.h"
@@ -33,10 +34,8 @@
 #include "bejavacoal.h"
 
 // only rematerialise when costs are less than REMAT_COST_LIMIT
-#define REMAT_COST_LIMIT       4
-
-/* This enables re-computation of values. Current state: Unfinished and buggy. */
-#undef BUGGY_REMAT
+// TODO determine a good value here...
+#define REMAT_COST_LIMIT       80
 
 typedef struct _reloader_t reloader_t;
 
@@ -54,6 +53,7 @@ typedef struct _spill_info_t {
 
 struct _spill_env_t {
        const arch_register_class_t *cls;
+       const arch_env_t *arch_env;
        const be_chordal_env_t *chordal_env;
        struct obstack obst;
        set *spills;                            /**< all spill_info_t's, which must be placed */
@@ -103,6 +103,7 @@ spill_env_t *be_new_spill_env(const be_chordal_env_t *chordal_env) {
        env->spills                     = new_set(cmp_spillinfo, 1024);
        env->cls                        = chordal_env->cls;
        env->chordal_env        = chordal_env;
+       env->arch_env       = env->chordal_env->birg->main_env->arch_env;
        env->mem_phis           = pset_new_ptr_default();
        obstack_init(&env->obst);
        return env;
@@ -130,7 +131,7 @@ void be_add_reload(spill_env_t *env, ir_node *to_spill, ir_node *before) {
        reloader_t *rel;
 
        assert(sched_is_scheduled(before));
-       assert(arch_irn_consider_in_reg_alloc(env->chordal_env->birg->main_env->arch_env, env->cls, to_spill));
+       assert(arch_irn_consider_in_reg_alloc(env->arch_env, env->cls, to_spill));
 
        info = get_spillinfo(env, to_spill);
 
@@ -230,7 +231,6 @@ static void sched_add_after_insn(ir_node *sched_after, ir_node *node) {
  * @return a be_Spill node
  */
 static void spill_irn(spill_env_t *env, spill_info_t *spillinfo) {
-       const be_main_env_t *mainenv = env->chordal_env->birg->main_env;
        ir_node *to_spill = spillinfo->spilled_node;
 
        DBG((env->dbg, LEVEL_1, "%+F\n", to_spill));
@@ -238,7 +238,7 @@ static void spill_irn(spill_env_t *env, spill_info_t *spillinfo) {
        /* Trying to spill an already spilled value, no need for a new spill
         * node then, we can simply connect to the same one for this reload
         *
-        * (although rematerialisation code should handle most of these cases
+        * (although rematerialization code should handle most of these cases
         * this can still happen when spilling Phis)
         */
        if(be_is_Reload(to_spill)) {
@@ -246,7 +246,14 @@ static void spill_irn(spill_env_t *env, spill_info_t *spillinfo) {
                return;
        }
 
-       spillinfo->spill = be_spill(mainenv->arch_env, to_spill);
+       if (arch_irn_is(env->arch_env, to_spill, dont_spill)) {
+               if (env->chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN)
+                       ir_fprintf(stderr, "Verify warning: spilling 'dont_spill' node %+F\n", to_spill);
+               else if (env->chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT)
+                       assert(0 && "Attempt to spill a node marked 'dont_spill'");
+       }
+
+       spillinfo->spill = be_spill(env->arch_env, to_spill);
        sched_add_after_insn(to_spill, spillinfo->spill);
 }
 
@@ -333,36 +340,41 @@ static int is_value_available(spill_env_t *env, ir_node *arg, ir_node *reloader)
        if(arg == get_irg_frame(env->chordal_env->irg))
                return 1;
 
-#if 0
-       /* we want to remat before the insn reloader
-        * thus an arguments is alive if
-        *   - it interferes with the reloaders result
-        * or
-        *   - or it is (last-) used by reloader itself
+       /* the following test does not work while spilling,
+        * because the liveness info is not adapted yet to the effects of the
+        * additional spills/reloads.
+        *
+        * So we can only do this test for ignore registers (of our register class)
         */
-       int i, m;
-
-       if (values_interfere(reloader, arg))
-               return 1;
+       if(arch_get_irn_reg_class(env->arch_env, arg, -1) == env->chordal_env->cls
+          && arch_irn_is(env->arch_env, arg, ignore)) {
+               int i, arity;
 
-       for (i=0, m=get_irn_arity(reloader); i<m; ++i) {
-               ir_node *rel_arg = get_irn_n(reloader, i);
-               if (rel_arg == arg)
+               /* we want to remat before the insn reloader
+                * thus an arguments is alive if
+                *   - it interferes with the reloaders result
+                *   - or it is (last-) used by reloader itself
+                */
+               if (values_interfere(env->chordal_env->lv, reloader, arg)) {
                        return 1;
-       }
+               }
 
-       /* arg is not alive before reloader */
-       return 0;
-#endif
+               arity = get_irn_arity(reloader);
+               for (i = 0; i < arity; ++i) {
+                       ir_node *rel_arg = get_irn_n(reloader, i);
+                       if (rel_arg == arg)
+                               return 1;
+               }
+       }
 
-       return 0;
+       return 0;
 }
 
 /**
  * Checks whether the node can principally be rematerialized
  */
 static int is_remat_node(spill_env_t *env, ir_node *node) {
-       const arch_env_t *arch_env = env->chordal_env->birg->main_env->arch_env;
+       const arch_env_t *arch_env = env->arch_env;
 
        assert(!be_is_Spill(node));
 
@@ -402,10 +414,8 @@ static int check_remat_conditions_costs(spill_env_t *env, ir_node *spilled, ir_n
 
        if(be_is_Reload(spilled)) {
                costs += 2;
-       } else if(is_Proj(spilled)) {
-               costs += 0;
        } else {
-               costs += 1;
+               costs += arch_get_op_estimated_cost(env->arch_env, spilled);
        }
        if(parentcosts + costs >= REMAT_COST_LIMIT)
                return REMAT_COST_LIMIT;
@@ -474,7 +484,6 @@ static ir_node *do_remat(spill_env_t *env, ir_node *spilled, ir_node *reloader)
        copy_node_attr(spilled, res);
 
        DBG((env->dbg, LEVEL_1, "Insert remat %+F before reloader %+F\n", res, reloader));
-       ir_printf("Insert remat %+F for %+F before reloader %+F(%s)\n", res, spilled, reloader, get_irg_dump_name(get_irn_irg(reloader)));
 
        /* insert in schedule */
        assert(!is_Block(reloader));
@@ -493,7 +502,7 @@ static ir_node *do_remat(spill_env_t *env, ir_node *spilled, ir_node *reloader)
  */
 
 void be_insert_spills_reloads(spill_env_t *env) {
-       const arch_env_t *arch_env = env->chordal_env->birg->main_env->arch_env;
+       const arch_env_t *arch_env = env->arch_env;
        spill_info_t *si;
 
        /* process each spilled node */