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* sh.c (calc_live_regs): If the return address pointer is live,
[pf3gnuchains/gcc-fork.git] / gcc / predict.c
index c00c864..e42eed0 100644 (file)
@@ -1,5 +1,5 @@
 /* Branch prediction routines for the GNU compiler.
-   Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
+   Copyright (C) 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
 
 This file is part of GCC.
 
@@ -30,6 +30,8 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 
 #include "config.h"
 #include "system.h"
+#include "coretypes.h"
+#include "tm.h"
 #include "tree.h"
 #include "rtl.h"
 #include "tm_p.h"
@@ -45,41 +47,39 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 #include "recog.h"
 #include "expr.h"
 #include "predict.h"
-#include "profile.h"
-#include "real.h"
+#include "coverage.h"
+#include "sreal.h"
 #include "params.h"
 #include "target.h"
+#include "loop.h"
+#include "cfgloop.h"
 
-/* real constants: 0, 1, 1-1/REG_BR_PROB_BASE, REG_BR_PROB_BASE, 0.5,
-                   REAL_BB_FREQ_MAX.  */
-static REAL_VALUE_TYPE real_zero, real_one, real_almost_one, real_br_prob_base,
-                      real_one_half, real_bb_freq_max;
+/* real constants: 0, 1, 1-1/REG_BR_PROB_BASE, REG_BR_PROB_BASE,
+                  1/REG_BR_PROB_BASE, 0.5, BB_FREQ_MAX.  */
+static sreal real_zero, real_one, real_almost_one, real_br_prob_base,
+            real_inv_br_prob_base, real_one_half, real_bb_freq_max;
 
 /* Random guesstimation given names.  */
-#define PROB_NEVER             (0)
 #define PROB_VERY_UNLIKELY     (REG_BR_PROB_BASE / 10 - 1)
-#define PROB_UNLIKELY          (REG_BR_PROB_BASE * 4 / 10 - 1)
 #define PROB_EVEN              (REG_BR_PROB_BASE / 2)
-#define PROB_LIKELY            (REG_BR_PROB_BASE - PROB_UNLIKELY)
 #define PROB_VERY_LIKELY       (REG_BR_PROB_BASE - PROB_VERY_UNLIKELY)
 #define PROB_ALWAYS            (REG_BR_PROB_BASE)
 
-static bool predicted_by_p              PARAMS ((basic_block,
-                                                 enum br_predictor));
-static void combine_predictions_for_insn PARAMS ((rtx, basic_block));
-static void dump_prediction             PARAMS ((enum br_predictor, int,
-                                                 basic_block, int));
-static void estimate_loops_at_level     PARAMS ((struct loop *loop));
-static void propagate_freq              PARAMS ((struct loop *));
-static void estimate_bb_frequencies     PARAMS ((struct loops *));
-static void counts_to_freqs             PARAMS ((void));
-static void process_note_predictions    PARAMS ((basic_block, int *, int *,
-                                                 sbitmap *));
-static void process_note_prediction     PARAMS ((basic_block, int *, int *,
-                                                 sbitmap *, int, int));
-static bool last_basic_block_p           PARAMS ((basic_block));
-static void compute_function_frequency  PARAMS ((void));
-static void choose_function_section     PARAMS ((void));
+static bool predicted_by_p (basic_block, enum br_predictor);
+static void combine_predictions_for_insn (rtx, basic_block);
+static void dump_prediction (enum br_predictor, int, basic_block, int);
+static void estimate_loops_at_level (struct loop *loop);
+static void propagate_freq (struct loop *);
+static void estimate_bb_frequencies (struct loops *);
+static void counts_to_freqs (void);
+static void process_note_predictions (basic_block, int *, dominance_info,
+                                     dominance_info);
+static void process_note_prediction (basic_block, int *, dominance_info,
+                                    dominance_info, int, int);
+static bool last_basic_block_p (basic_block);
+static void compute_function_frequency (void);
+static void choose_function_section (void);
+static bool can_predict_insn_p (rtx);
 
 /* Information we hold about each branch predictor.
    Filled using information from predict.def.  */
@@ -110,17 +110,14 @@ static const struct predictor_info predictor_info[]= {
 #undef DEF_PREDICTOR
 
 /* Return true in case BB can be CPU intensive and should be optimized
-   for maximal perofmrance.  */
+   for maximal performance.  */
 
 bool
-maybe_hot_bb_p (bb)
-     basic_block bb;
+maybe_hot_bb_p (basic_block bb)
 {
-  if (profile_info.count_profiles_merged
-      && flag_branch_probabilities
+  if (profile_info && flag_branch_probabilities
       && (bb->count
-         < profile_info.max_counter_in_program
-         / PARAM_VALUE (HOT_BB_COUNT_FRACTION)))
+         < profile_info->sum_max / PARAM_VALUE (HOT_BB_COUNT_FRACTION)))
     return false;
   if (bb->frequency < BB_FREQ_MAX / PARAM_VALUE (HOT_BB_FREQUENCY_FRACTION))
     return false;
@@ -130,14 +127,11 @@ maybe_hot_bb_p (bb)
 /* Return true in case BB is cold and should be optimized for size.  */
 
 bool
-probably_cold_bb_p (bb)
-     basic_block bb;
+probably_cold_bb_p (basic_block bb)
 {
-  if (profile_info.count_profiles_merged
-      && flag_branch_probabilities
+  if (profile_info && flag_branch_probabilities
       && (bb->count
-         < profile_info.max_counter_in_program
-         / PARAM_VALUE (HOT_BB_COUNT_FRACTION)))
+         < profile_info->sum_max / PARAM_VALUE (HOT_BB_COUNT_FRACTION)))
     return true;
   if (bb->frequency < BB_FREQ_MAX / PARAM_VALUE (HOT_BB_FREQUENCY_FRACTION))
     return true;
@@ -146,13 +140,10 @@ probably_cold_bb_p (bb)
 
 /* Return true in case BB is probably never executed.  */
 bool
-probably_never_executed_bb_p (bb)
-       basic_block bb;
+probably_never_executed_bb_p (basic_block bb)
 {
-  if (profile_info.count_profiles_merged
-      && flag_branch_probabilities)
-    return ((bb->count + profile_info.count_profiles_merged / 2)
-           / profile_info.count_profiles_merged) == 0;
+  if (profile_info && flag_branch_probabilities)
+    return ((bb->count + profile_info->runs / 2) / profile_info->runs) == 0;
   return false;
 }
 
@@ -160,9 +151,7 @@ probably_never_executed_bb_p (bb)
    PREDICTOR.  */
 
 static bool
-predicted_by_p (bb, predictor)
-     basic_block bb;
-     enum br_predictor predictor;
+predicted_by_p (basic_block bb, enum br_predictor predictor)
 {
   rtx note;
   if (!INSN_P (bb->end))
@@ -175,13 +164,12 @@ predicted_by_p (bb, predictor)
 }
 
 void
-predict_insn (insn, predictor, probability)
-     rtx insn;
-     int probability;
-     enum br_predictor predictor;
+predict_insn (rtx insn, enum br_predictor predictor, int probability)
 {
   if (!any_condjump_p (insn))
     abort ();
+  if (!flag_guess_branch_prob)
+    return;
 
   REG_NOTES (insn)
     = gen_rtx_EXPR_LIST (REG_BR_PRED,
@@ -194,10 +182,8 @@ predict_insn (insn, predictor, probability)
 /* Predict insn by given predictor.  */
 
 void
-predict_insn_def (insn, predictor, taken)
-     rtx insn;
-     enum br_predictor predictor;
-     enum prediction taken;
+predict_insn_def (rtx insn, enum br_predictor predictor,
+                 enum prediction taken)
 {
    int probability = predictor_info[(int) predictor].hitrate;
 
@@ -210,10 +196,7 @@ predict_insn_def (insn, predictor, taken)
 /* Predict edge E with given probability if possible.  */
 
 void
-predict_edge (e, predictor, probability)
-     edge e;
-     int probability;
-     enum br_predictor predictor;
+predict_edge (edge e, enum br_predictor predictor, int probability)
 {
   rtx last_insn;
   last_insn = e->src->end;
@@ -230,13 +213,22 @@ predict_edge (e, predictor, probability)
   predict_insn (last_insn, predictor, probability);
 }
 
+/* Return true when we can store prediction on insn INSN.
+   At the moment we represent predictions only on conditional
+   jumps, not at computed jump or other complicated cases.  */
+static bool
+can_predict_insn_p (rtx insn)
+{
+  return (GET_CODE (insn) == JUMP_INSN
+         && any_condjump_p (insn)
+         && BLOCK_FOR_INSN (insn)->succ->succ_next);
+}
+
 /* Predict edge E by given predictor if possible.  */
 
 void
-predict_edge_def (e, predictor, taken)
-     edge e;
-     enum br_predictor predictor;
-     enum prediction taken;
+predict_edge_def (edge e, enum br_predictor predictor,
+                 enum prediction taken)
 {
    int probability = predictor_info[(int) predictor].hitrate;
 
@@ -250,8 +242,7 @@ predict_edge_def (e, predictor, taken)
    to be done each time we invert the condition used by the jump.  */
 
 void
-invert_br_probabilities (insn)
-     rtx insn;
+invert_br_probabilities (rtx insn)
 {
   rtx note;
 
@@ -266,11 +257,8 @@ invert_br_probabilities (insn)
 /* Dump information about the branch prediction to the output file.  */
 
 static void
-dump_prediction (predictor, probability, bb, used)
-     enum br_predictor predictor;
-     int probability;
-     basic_block bb;
-     int used;
+dump_prediction (enum br_predictor predictor, int probability,
+                basic_block bb, int used)
 {
   edge e = bb->succ;
 
@@ -303,9 +291,7 @@ dump_prediction (predictor, probability, bb, used)
    note if not already present.  Remove now useless REG_BR_PRED notes.  */
 
 static void
-combine_predictions_for_insn (insn, bb)
-     rtx insn;
-     basic_block bb;
+combine_predictions_for_insn (rtx insn, basic_block bb)
 {
   rtx prob_note = find_reg_note (insn, REG_BR_PROB, 0);
   rtx *pnote = &REG_NOTES (insn);
@@ -405,30 +391,48 @@ combine_predictions_for_insn (insn, bb)
    predictions).  */
 
 void
-estimate_probability (loops_info)
-     struct loops *loops_info;
+estimate_probability (struct loops *loops_info)
 {
-  sbitmap *dominators, *post_dominators;
+  dominance_info dominators, post_dominators;
   basic_block bb;
-  int i;
+  unsigned i;
 
-  dominators = sbitmap_vector_alloc (last_basic_block, last_basic_block);
-  post_dominators = sbitmap_vector_alloc (last_basic_block, last_basic_block);
-  calculate_dominance_info (NULL, dominators, CDI_DOMINATORS);
-  calculate_dominance_info (NULL, post_dominators, CDI_POST_DOMINATORS);
+  connect_infinite_loops_to_exit ();
+  dominators = calculate_dominance_info (CDI_DOMINATORS);
+  post_dominators = calculate_dominance_info (CDI_POST_DOMINATORS);
 
   /* Try to predict out blocks in a loop that are not part of a
      natural loop.  */
   for (i = 1; i < loops_info->num; i++)
     {
       basic_block bb, *bbs;
-      int j;
+      unsigned j;
       int exits;
       struct loop *loop = loops_info->parray[i];
+      struct loop_desc desc;
+      unsigned HOST_WIDE_INT niter;
 
       flow_loop_scan (loops_info, loop, LOOP_EXIT_EDGES);
       exits = loop->num_exits;
 
+      if (simple_loop_p (loops_info, loop, &desc)
+         && desc.const_iter)
+       {
+         int prob;
+         niter = desc.niter + 1;
+         if (niter == 0)        /* We might overflow here.  */
+           niter = desc.niter;
+
+         prob = (REG_BR_PROB_BASE
+                 - (REG_BR_PROB_BASE + niter /2) / niter);
+         /* Branch prediction algorithm gives 0 frequency for everything
+            after the end of loop for loop having 0 probability to finish.  */
+         if (prob == REG_BR_PROB_BASE)
+           prob = REG_BR_PROB_BASE - 1;
+         predict_edge (desc.in_edge, PRED_LOOP_ITERATIONS,
+                       prob);
+       }
+
       bbs = get_loop_body (loop);
       for (j = 0; j < loop->num_nodes; j++)
        {
@@ -441,7 +445,8 @@ estimate_probability (loops_info)
             statements construct loops via "non-loop" constructs
             in the source language and are better to be handled
             separately.  */
-         if (predicted_by_p (bb, PRED_CONTINUE))
+         if (!can_predict_insn_p (bb->end)
+             || predicted_by_p (bb, PRED_CONTINUE))
            continue;
 
          /* Loop branch heuristics - predict an edge back to a
@@ -455,7 +460,7 @@ estimate_probability (loops_info)
              }
 
          /* Loop exit heuristics - predict an edge exiting the loop if the
-            conditinal has no loop header successors as not taken.  */
+            conditional has no loop header successors as not taken.  */
          if (!header_found)
            for (e = bb->succ; e; e = e->succ_next)
              if (e->dest->index < 0
@@ -475,7 +480,7 @@ estimate_probability (loops_info)
       rtx cond, earliest;
       edge e;
 
-      if (GET_CODE (last_insn) != JUMP_INSN || ! any_condjump_p (last_insn))
+      if (! can_predict_insn_p (last_insn))
        continue;
 
       for (e = bb->succ; e; e = e->succ_next)
@@ -495,8 +500,8 @@ estimate_probability (loops_info)
          /* Look for block we are guarding (ie we dominate it,
             but it doesn't postdominate us).  */
          if (e->dest != EXIT_BLOCK_PTR && e->dest != bb
-             && TEST_BIT (dominators[e->dest->index], e->src->index)
-             && !TEST_BIT (post_dominators[e->src->index], e->dest->index))
+             && dominated_by_p (dominators, e->dest, e->src)
+             && !dominated_by_p (post_dominators, e->src, e->dest))
            {
              rtx insn;
 
@@ -550,12 +555,12 @@ estimate_probability (loops_info)
          case EQ:
          case UNEQ:
            /* Floating point comparisons appears to behave in a very
-              inpredictable way because of special role of = tests in
+              unpredictable way because of special role of = tests in
               FP code.  */
            if (FLOAT_MODE_P (GET_MODE (XEXP (cond, 0))))
              ;
            /* Comparisons with 0 are often used for booleans and there is
-              nothing usefull to predict about them.  */
+              nothing useful to predict about them.  */
            else if (XEXP (cond, 1) == const0_rtx
                     || XEXP (cond, 0) == const0_rtx)
              ;
@@ -566,12 +571,12 @@ estimate_probability (loops_info)
          case NE:
          case LTGT:
            /* Floating point comparisons appears to behave in a very
-              inpredictable way because of special role of = tests in
+              unpredictable way because of special role of = tests in
               FP code.  */
            if (FLOAT_MODE_P (GET_MODE (XEXP (cond, 0))))
              ;
            /* Comparisons with 0 are often used for booleans and there is
-              nothing usefull to predict about them.  */
+              nothing useful to predict about them.  */
            else if (XEXP (cond, 1) == const0_rtx
                     || XEXP (cond, 0) == const0_rtx)
              ;
@@ -613,9 +618,10 @@ estimate_probability (loops_info)
        && bb->succ->succ_next != NULL)
       combine_predictions_for_insn (bb->end, bb);
 
-  sbitmap_vector_free (post_dominators);
-  sbitmap_vector_free (dominators);
+  free_dominance_info (post_dominators);
+  free_dominance_info (dominators);
 
+  remove_fake_edges ();
   estimate_bb_frequencies (loops_info);
 }
 \f
@@ -624,7 +630,7 @@ estimate_probability (loops_info)
    values.  */
 
 void
-expected_value_to_br_prob ()
+expected_value_to_br_prob (void)
 {
   rtx insn, cond, ev = NULL_RTX, ev_reg = NULL_RTX;
 
@@ -692,11 +698,10 @@ expected_value_to_br_prob ()
     }
 }
 \f
-/* Check whether this is the last basic block of function.  Commonly tehre
-   is one extra common cleanup block.  */
+/* Check whether this is the last basic block of function.  Commonly
+   there is one extra common cleanup block.  */
 static bool
-last_basic_block_p (bb)
-     basic_block bb;
+last_basic_block_p (basic_block bb)
 {
   if (bb == EXIT_BLOCK_PTR)
     return false;
@@ -707,20 +712,17 @@ last_basic_block_p (bb)
              && bb->succ->dest->next_bb == EXIT_BLOCK_PTR));
 }
 
-/* Sets branch probabilities according to PREDiction and FLAGS. HEADS[bb->index]
-   should be index of basic block in that we need to alter branch predictions
-   (i.e. the first of our dominators such that we do not post-dominate it)
-   (but we fill this information on demand, so -1 may be there in case this
-   was not needed yet).  */
+/* Sets branch probabilities according to PREDiction and
+   FLAGS. HEADS[bb->index] should be index of basic block in that we
+   need to alter branch predictions (i.e. the first of our dominators
+   such that we do not post-dominate it) (but we fill this information
+   on demand, so -1 may be there in case this was not needed yet).  */
 
 static void
-process_note_prediction (bb, heads, dominators, post_dominators, pred, flags)
-     basic_block bb;
-     int *heads;
-     int *dominators;
-     sbitmap *post_dominators;
-     int pred;
-     int flags;
+process_note_prediction (basic_block bb, int *heads,
+                        dominance_info dominators,
+                        dominance_info post_dominators, int pred,
+                        int flags)
 {
   edge e;
   int y;
@@ -733,38 +735,41 @@ process_note_prediction (bb, heads, dominators, post_dominators, pred, flags)
       /* This is first time we need this field in heads array; so
          find first dominator that we do not post-dominate (we are
          using already known members of heads array).  */
-      int ai = bb->index;
-      int next_ai = dominators[bb->index];
+      basic_block ai = bb;
+      basic_block next_ai = get_immediate_dominator (dominators, bb);
       int head;
 
-      while (heads[next_ai] < 0)
+      while (heads[next_ai->index] < 0)
        {
-         if (!TEST_BIT (post_dominators[next_ai], bb->index))
+         if (!dominated_by_p (post_dominators, next_ai, bb))
            break;
-         heads[next_ai] = ai;
+         heads[next_ai->index] = ai->index;
          ai = next_ai;
-         next_ai = dominators[next_ai];
+         next_ai = get_immediate_dominator (dominators, next_ai);
        }
-      if (!TEST_BIT (post_dominators[next_ai], bb->index))
-       head = next_ai;
+      if (!dominated_by_p (post_dominators, next_ai, bb))
+       head = next_ai->index;
       else
-       head = heads[next_ai];
-      while (next_ai != bb->index)
+       head = heads[next_ai->index];
+      while (next_ai != bb)
        {
          next_ai = ai;
-         ai = heads[ai];
-         heads[next_ai] = head;
+         if (heads[ai->index] == ENTRY_BLOCK)
+           ai = ENTRY_BLOCK_PTR;
+         else
+           ai = BASIC_BLOCK (heads[ai->index]);
+         heads[next_ai->index] = head;
        }
     }
   y = heads[bb->index];
 
   /* Now find the edge that leads to our branch and aply the prediction.  */
 
-  if (y == last_basic_block)
+  if (y == last_basic_block || !can_predict_insn_p (BASIC_BLOCK (y)->end))
     return;
   for (e = BASIC_BLOCK (y)->succ; e; e = e->succ_next)
     if (e->dest->index >= 0
-       && TEST_BIT (post_dominators[e->dest->index], bb->index))
+       && dominated_by_p (post_dominators, e->dest, bb))
       predict_edge_def (e, pred, taken);
 }
 
@@ -773,16 +778,14 @@ process_note_prediction (bb, heads, dominators, post_dominators, pred, flags)
    process_note_prediction.  */
 
 static void
-process_note_predictions (bb, heads, dominators, post_dominators)
-     basic_block bb;
-     int *heads;
-     int *dominators;
-     sbitmap *post_dominators;
+process_note_predictions (basic_block bb, int *heads,
+                         dominance_info dominators,
+                         dominance_info post_dominators)
 {
   rtx insn;
   edge e;
 
-  /* Additionaly, we check here for blocks with no successors.  */
+  /* Additionally, we check here for blocks with no successors.  */
   int contained_noreturn_call = 0;
   int was_bb_head = 0;
   int noreturn_block = 1;
@@ -835,21 +838,18 @@ process_note_predictions (bb, heads, dominators, post_dominators)
    branch probabilities.  */
 
 void
-note_prediction_to_br_prob ()
+note_prediction_to_br_prob (void)
 {
   basic_block bb;
-  sbitmap *post_dominators;
-  int *dominators, *heads;
+  dominance_info post_dominators, dominators;
+  int *heads;
 
   /* To enable handling of noreturn blocks.  */
   add_noreturn_fake_exit_edges ();
   connect_infinite_loops_to_exit ();
 
-  dominators = xmalloc (sizeof (int) * last_basic_block);
-  memset (dominators, -1, sizeof (int) * last_basic_block);
-  post_dominators = sbitmap_vector_alloc (last_basic_block, last_basic_block);
-  calculate_dominance_info (NULL, post_dominators, CDI_POST_DOMINATORS);
-  calculate_dominance_info (dominators, NULL, CDI_DOMINATORS);
+  post_dominators = calculate_dominance_info (CDI_POST_DOMINATORS);
+  dominators = calculate_dominance_info (CDI_DOMINATORS);
 
   heads = xmalloc (sizeof (int) * last_basic_block);
   memset (heads, -1, sizeof (int) * last_basic_block);
@@ -860,8 +860,8 @@ note_prediction_to_br_prob ()
   FOR_EACH_BB (bb)
     process_note_predictions (bb, heads, dominators, post_dominators);
 
-  sbitmap_vector_free (post_dominators);
-  free (dominators);
+  free_dominance_info (post_dominators);
+  free_dominance_info (dominators);
   free (heads);
 
   remove_fake_edges ();
@@ -873,7 +873,7 @@ note_prediction_to_br_prob ()
 typedef struct block_info_def
 {
   /* Estimated frequency of execution of basic_block.  */
-  REAL_VALUE_TYPE frequency;
+  sreal frequency;
 
   /* To keep queue of basic blocks to process.  */
   basic_block next;
@@ -891,7 +891,7 @@ typedef struct edge_info_def
   /* In case edge is an loopback edge, the probability edge will be reached
      in case header is.  Estimated number of iterations of the loop can be
      then computed as 1 / (1 - back_edge_prob).  */
-  REAL_VALUE_TYPE back_edge_prob;
+  sreal back_edge_prob;
   /* True if the edge is an loopback edge in the natural loop.  */
   int back_edge:1;
 } *edge_info;
@@ -903,8 +903,7 @@ typedef struct edge_info_def
    Propagate the frequencies for LOOP.  */
 
 static void
-propagate_freq (loop)
-     struct loop *loop;
+propagate_freq (struct loop *loop)
 {
   basic_block head = loop->header;
   basic_block bb;
@@ -936,7 +935,7 @@ propagate_freq (loop)
   last = head;
   for (bb = head; bb; bb = nextbb)
     {
-      REAL_VALUE_TYPE cyclic_probability, frequency;
+      sreal cyclic_probability, frequency;
 
       memcpy (&cyclic_probability, &real_zero, sizeof (real_zero));
       memcpy (&frequency, &real_zero, sizeof (real_zero));
@@ -956,36 +955,43 @@ propagate_freq (loop)
          for (e = bb->pred; e; e = e->pred_next)
            if (EDGE_INFO (e)->back_edge)
              {
-               REAL_ARITHMETIC (cyclic_probability, PLUS_EXPR,
-                                cyclic_probability,
-                                EDGE_INFO (e)->back_edge_prob);
+               sreal_add (&cyclic_probability, &cyclic_probability,
+                          &EDGE_INFO (e)->back_edge_prob);
              }
            else if (!(e->flags & EDGE_DFS_BACK))
              {
-               REAL_VALUE_TYPE tmp;
+               sreal tmp;
 
                /*  frequency += (e->probability
                                  * BLOCK_INFO (e->src)->frequency /
                                  REG_BR_PROB_BASE);  */
 
-               REAL_VALUE_FROM_INT (tmp, e->probability, 0,
-                                    TYPE_MODE (double_type_node));
-               REAL_ARITHMETIC (tmp, MULT_EXPR, tmp,
-                                BLOCK_INFO (e->src)->frequency);
-               REAL_ARITHMETIC (tmp, RDIV_EXPR, tmp, real_br_prob_base);
-               REAL_ARITHMETIC (frequency, PLUS_EXPR, frequency, tmp);
+               sreal_init (&tmp, e->probability, 0);
+               sreal_mul (&tmp, &tmp, &BLOCK_INFO (e->src)->frequency);
+               sreal_mul (&tmp, &tmp, &real_inv_br_prob_base);
+               sreal_add (&frequency, &frequency, &tmp);
              }
 
-         if (REAL_VALUES_LESS (real_almost_one, cyclic_probability))
-           memcpy (&cyclic_probability, &real_almost_one, sizeof (real_zero));
+         if (sreal_compare (&cyclic_probability, &real_zero) == 0)
+           {
+             memcpy (&BLOCK_INFO (bb)->frequency, &frequency,
+                     sizeof (frequency));
+           }
+         else
+           {
+             if (sreal_compare (&cyclic_probability, &real_almost_one) > 0)
+               {
+                 memcpy (&cyclic_probability, &real_almost_one,
+                         sizeof (real_almost_one));
+               }
 
-         /* BLOCK_INFO (bb)->frequency = frequency / (1 - cyclic_probability)
-          */
+             /* BLOCK_INFO (bb)->frequency = frequency
+                                             / (1 - cyclic_probability) */
 
-         REAL_ARITHMETIC (cyclic_probability, MINUS_EXPR, real_one,
-                          cyclic_probability);
-         REAL_ARITHMETIC (BLOCK_INFO (bb)->frequency,
-                          RDIV_EXPR, frequency, cyclic_probability);
+             sreal_sub (&cyclic_probability, &real_one, &cyclic_probability);
+             sreal_div (&BLOCK_INFO (bb)->frequency,
+                        &frequency, &cyclic_probability);
+           }
        }
 
       BLOCK_INFO (bb)->tovisit = 0;
@@ -994,18 +1000,16 @@ propagate_freq (loop)
       for (e = bb->succ; e; e = e->succ_next)
        if (e->dest == head)
          {
-           REAL_VALUE_TYPE tmp;
+           sreal tmp;
 
            /* EDGE_INFO (e)->back_edge_prob
                  = ((e->probability * BLOCK_INFO (bb)->frequency)
                     / REG_BR_PROB_BASE); */
-           REAL_VALUE_FROM_INT (tmp, e->probability, 0,
-                                TYPE_MODE (double_type_node));
-           REAL_ARITHMETIC (tmp, MULT_EXPR, tmp,
-                            BLOCK_INFO (bb)->frequency);
-           REAL_ARITHMETIC (EDGE_INFO (e)->back_edge_prob,
-                            RDIV_EXPR, tmp, real_br_prob_base);
 
+           sreal_init (&tmp, e->probability, 0);
+           sreal_mul (&tmp, &tmp, &BLOCK_INFO (bb)->frequency);
+           sreal_mul (&EDGE_INFO (e)->back_edge_prob,
+                      &tmp, &real_inv_br_prob_base);
          }
 
       /* Propagate to successor blocks.  */
@@ -1030,8 +1034,7 @@ propagate_freq (loop)
 /* Estimate probabilities of loopback edges in loops at same nest level.  */
 
 static void
-estimate_loops_at_level (first_loop)
-     struct loop *first_loop;
+estimate_loops_at_level (struct loop *first_loop)
 {
   struct loop *loop;
 
@@ -1039,10 +1042,10 @@ estimate_loops_at_level (first_loop)
     {
       edge e;
       basic_block *bbs;
-      int i;
+      unsigned i;
 
       estimate_loops_at_level (loop->inner);
-      
+
       if (loop->latch->succ)  /* Do not do this for dummy function loop.  */
        {
          /* Find current loop back edge and mark it.  */
@@ -1061,9 +1064,9 @@ estimate_loops_at_level (first_loop)
 /* Convert counts measured by profile driven feedback to frequencies.  */
 
 static void
-counts_to_freqs ()
+counts_to_freqs (void)
 {
-  HOST_WIDEST_INT count_max = 1;
+  gcov_type count_max = 1;
   basic_block bb;
 
   FOR_EACH_BB (bb)
@@ -1075,12 +1078,11 @@ counts_to_freqs ()
 
 /* Return true if function is likely to be expensive, so there is no point to
    optimize performance of prologue, epilogue or do inlining at the expense
-   of code size growth.  THRESHOLD is the limit of number of isntructions
+   of code size growth.  THRESHOLD is the limit of number of instructions
    function can execute at average to be still considered not expensive.  */
 
 bool
-expensive_function_p (threshold)
-       int threshold;
+expensive_function_p (int threshold)
 {
   unsigned int sum = 0;
   basic_block bb;
@@ -1119,27 +1121,28 @@ expensive_function_p (threshold)
 /* Estimate basic blocks frequency by given branch probabilities.  */
 
 static void
-estimate_bb_frequencies (loops)
-     struct loops *loops;
+estimate_bb_frequencies (struct loops *loops)
 {
   basic_block bb;
-  REAL_VALUE_TYPE freq_max;
-  enum machine_mode double_mode = TYPE_MODE (double_type_node);
+  sreal freq_max;
 
   if (flag_branch_probabilities)
     counts_to_freqs ();
   else
     {
-      REAL_VALUE_FROM_INT (real_zero, 0, 0, double_mode);
-      REAL_VALUE_FROM_INT (real_one, 1, 0, double_mode);
-      REAL_VALUE_FROM_INT (real_br_prob_base, REG_BR_PROB_BASE, 0, double_mode);
-      REAL_VALUE_FROM_INT (real_bb_freq_max, BB_FREQ_MAX, 0, double_mode);
-      REAL_VALUE_FROM_INT (real_one_half, 2, 0, double_mode);
-
-      REAL_ARITHMETIC (real_one_half, RDIV_EXPR, real_one, real_one_half);
-
-      REAL_ARITHMETIC (real_almost_one, RDIV_EXPR, real_one, real_br_prob_base);
-      REAL_ARITHMETIC (real_almost_one, MINUS_EXPR, real_one, real_almost_one);
+      static int real_values_initialized = 0;
+
+      if (!real_values_initialized)
+        {
+         real_values_initialized = 1;
+         sreal_init (&real_zero, 0, 0);
+         sreal_init (&real_one, 1, 0);
+         sreal_init (&real_br_prob_base, REG_BR_PROB_BASE, 0);
+         sreal_init (&real_bb_freq_max, BB_FREQ_MAX, 0);
+         sreal_init (&real_one_half, 1, -1);
+         sreal_div (&real_inv_br_prob_base, &real_one, &real_br_prob_base);
+         sreal_sub (&real_almost_one, &real_one, &real_inv_br_prob_base);
+       }
 
       mark_dfs_back_edges ();
       /* Fill in the probability values in flowgraph based on the REG_BR_PROB
@@ -1148,9 +1151,7 @@ estimate_bb_frequencies (loops)
        {
          rtx last_insn = bb->end;
 
-         if (GET_CODE (last_insn) != JUMP_INSN || !any_condjump_p (last_insn)
-             /* Avoid handling of conditional jumps jumping to fallthru edge.  */
-             || bb->succ->succ_next == NULL)
+         if (!can_predict_insn_p (last_insn))
            {
              /* We can predict only conditional jumps at the moment.
                 Expect each edge to be equally probable.
@@ -1182,11 +1183,10 @@ estimate_bb_frequencies (loops)
          BLOCK_INFO (bb)->tovisit = 0;
          for (e = bb->succ; e; e = e->succ_next)
            {
-             REAL_VALUE_FROM_INT (EDGE_INFO (e)->back_edge_prob,
-                                  e->probability, 0, double_mode);
-             REAL_ARITHMETIC (EDGE_INFO (e)->back_edge_prob,
-                              RDIV_EXPR, EDGE_INFO (e)->back_edge_prob,
-                              real_br_prob_base);
+             sreal_init (&EDGE_INFO (e)->back_edge_prob, e->probability, 0);
+             sreal_mul (&EDGE_INFO (e)->back_edge_prob,
+                        &EDGE_INFO (e)->back_edge_prob,
+                        &real_inv_br_prob_base);
            }
        }
 
@@ -1196,20 +1196,17 @@ estimate_bb_frequencies (loops)
 
       memcpy (&freq_max, &real_zero, sizeof (real_zero));
       FOR_EACH_BB (bb)
-       if (REAL_VALUES_LESS
-           (freq_max, BLOCK_INFO (bb)->frequency))
-         memcpy (&freq_max, &BLOCK_INFO (bb)->frequency,
-                 sizeof (freq_max));
+       if (sreal_compare (&freq_max, &BLOCK_INFO (bb)->frequency) < 0)
+         memcpy (&freq_max, &BLOCK_INFO (bb)->frequency, sizeof (freq_max));
 
+      sreal_div (&freq_max, &real_bb_freq_max, &freq_max);
       FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
        {
-         REAL_VALUE_TYPE tmp;
+         sreal tmp;
 
-         REAL_ARITHMETIC (tmp, MULT_EXPR, BLOCK_INFO (bb)->frequency,
-                          real_bb_freq_max);
-         REAL_ARITHMETIC (tmp, RDIV_EXPR, tmp, freq_max);
-         REAL_ARITHMETIC (tmp, PLUS_EXPR, tmp, real_one_half);
-         bb->frequency = REAL_VALUE_UNSIGNED_FIX (tmp);
+         sreal_mul (&tmp, &BLOCK_INFO (bb)->frequency, &freq_max);
+         sreal_add (&tmp, &tmp, &real_one_half);
+         bb->frequency = sreal_to_int (&tmp);
        }
 
       free_aux_for_blocks ();
@@ -1222,12 +1219,11 @@ estimate_bb_frequencies (loops)
 
 /* Decide whether function is hot, cold or unlikely executed.  */
 static void
-compute_function_frequency ()
+compute_function_frequency (void)
 {
   basic_block bb;
 
-  if (!profile_info.count_profiles_merged
-      || !flag_branch_probabilities)
+  if (!profile_info || !flag_branch_probabilities)
     return;
   cfun->function_frequency = FUNCTION_FREQUENCY_UNLIKELY_EXECUTED;
   FOR_EACH_BB (bb)
@@ -1244,10 +1240,15 @@ compute_function_frequency ()
 
 /* Choose appropriate section for the function.  */
 static void
-choose_function_section ()
+choose_function_section (void)
 {
   if (DECL_SECTION_NAME (current_function_decl)
-      || !targetm.have_named_sections)
+      || !targetm.have_named_sections
+      /* Theoretically we can split the gnu.linkonce text section too,
+        but this requires more work as the frequency needs to match
+        for all generated objects so we need to merge the frequency
+        of all instances.  For now just never set frequency for these.  */
+      || DECL_ONE_ONLY (current_function_decl))
     return;
   if (cfun->function_frequency == FUNCTION_FREQUENCY_HOT)
     DECL_SECTION_NAME (current_function_decl) =