[multiple changes]

2012-10-15   Easwaran Raman  <eraman@google.com>

        * optabs.c (emit_cmp_and_jump_insn_1): Add a new parameter to
        specificy the probability of taking the jump.
        (emit_cmp_and_jump_insns): Likewise.
        (expand_compare_and_swap_loop): Make the jump predicted not taken.
        * dojump.c (do_compare_rtx_and_jump): Remove the code attaching
        REG_BR_PROB note and pass probability to emit_cmp_and_jump_insns.
        * cfgbuild.c (compute_outgoing_frequencies): Do not guess outgoing
        probabilities for branches with more than two successors.
        * expr.c (emit_block_move_via_loop): Predict the loop backedge loop
        to be highly taken.
        (try_casesi): Pass the probability of jumping to the default label.
        (try_tablejump): Likewise.
        (do_tablejump): Likewise.
        * expr.h (try_tablejump): Add a new parameter.
        (try_casesi): Likewise.
        (emit_cmp_and_jump_insns): Add probability as default parameter with a
        default value of -1.
        * except.c (sjlj_emit_function_enter): Pass probability to
        emit_cmp_and_jump_insns.
        * stmt.c (case_node): Add new fields PROB and SUBTREE_PROB.
        (do_jump_if_equal): Pass probability for REG_BR_PROB note.
        (add_case_node): Pass estimated probability of jumping to the case
        label.
        (emit_case_decision_tree): Pass default_prob to emit_case_nodes.
        (get_outgoing_edge_probs): New function.
        (conditional_probability): Likewise.
        (reset_out_edges_aux): Likewise.
        (compute_cases_per_edge): Likewise.
        (emit_case_dispatch_table): Update probabilities of edges coming out
        of the switch statement.
        (expand_case): Compute and propagate default edge probability to
        emit_case_dispatch_table.
        (expand_sjlj_dispatch_table): Update calls to add_case_node and
        emit_case_dispatch_table.
        (balance_case_nodes): Update subtree_prob values.
        (emit_case_nodes): Compute edge probabilities and add pass them to
        emit_cmp_and_jump_insns.

testsuite/ChangeLog:
2012-10-15   Easwaran Raman  <eraman@google.com> 
        * gcc.dg/tree-prof/switch-case-1.c: New test case.
        * gcc.dg/tree-prof/switch-case-2.c: New test case.

From-SVN: r192488

gcc/ChangeLog

+2012-10-15   Easwaran Raman  <eraman@google.com>
+
+	* optabs.c (emit_cmp_and_jump_insn_1): Add a new parameter to
+	specificy the probability of taking the jump.
+	(emit_cmp_and_jump_insns): Likewise.
+	(expand_compare_and_swap_loop): Make the jump predicted not taken.
+	* dojump.c (do_compare_rtx_and_jump): Remove the code attaching
+	REG_BR_PROB note and pass probability to emit_cmp_and_jump_insns.
+	* cfgbuild.c (compute_outgoing_frequencies): Do not guess outgoing
+	probabilities for branches with more than two successors.
+	* expr.c (emit_block_move_via_loop): Predict the loop backedge loop
+	to be highly taken.
+	(try_casesi): Pass the probability of jumping to the default label.
+	(try_tablejump): Likewise.
+	(do_tablejump): Likewise.
+	* expr.h (try_tablejump): Add a new parameter.
+	(try_casesi): Likewise.
+	(emit_cmp_and_jump_insns): Add probability as default parameter with a
+	default value of -1.
+	* except.c (sjlj_emit_function_enter): Pass probability to
+	emit_cmp_and_jump_insns.
+	* stmt.c (case_node): Add new fields PROB and SUBTREE_PROB.
+	(do_jump_if_equal): Pass probability for REG_BR_PROB note.
+	(add_case_node): Pass estimated probability of jumping to the case
+	label.
+	(emit_case_decision_tree): Pass default_prob to emit_case_nodes.
+	(get_outgoing_edge_probs): New function.
+	(conditional_probability): Likewise.
+	(reset_out_edges_aux): Likewise.
+	(compute_cases_per_edge): Likewise.
+	(emit_case_dispatch_table): Update probabilities of edges coming out
+	of the switch statement.
+	(expand_case): Compute and propagate default edge probability to
+	emit_case_dispatch_table.
+	(expand_sjlj_dispatch_table): Update calls to add_case_node and
+	emit_case_dispatch_table.
+	(balance_case_nodes): Update subtree_prob values.
+	(emit_case_nodes): Compute edge probabilities and add pass them to
+	emit_cmp_and_jump_insns.
+
 2012-10-15  Oleg Endo  <olegendo@gcc.gnu.org>
 
 	PR target/51244

gcc/cfgbuild.c

@@ -559,16 +559,35 @@ compute_outgoing_frequencies (basic_block b)
 	  f->count = b->count - e->count;
 	  return;
 	}
+      else
+        {
+          guess_outgoing_edge_probabilities (b);
+        }
     }
-
-  if (single_succ_p (b))
+  else if (single_succ_p (b))
     {
       e = single_succ_edge (b);
       e->probability = REG_BR_PROB_BASE;
       e->count = b->count;
       return;
     }
-  guess_outgoing_edge_probabilities (b);
+  else
+    {
+      /* We rely on BBs with more than two successors to have sane probabilities
+         and do not guess them here. For BBs terminated by switch statements
+         expanded to jump-table jump, we have done the right thing during
+         expansion. For EH edges, we still guess the probabilities here.  */
+      bool complex_edge = false;
+      FOR_EACH_EDGE (e, ei, b->succs)
+        if (e->flags & EDGE_COMPLEX)
+          {
+            complex_edge = true;
+            break;
+          }
+      if (complex_edge)
+        guess_outgoing_edge_probabilities (b);
+    }
+
   if (b->count)
     FOR_EACH_EDGE (e, ei, b->succs)
       e->count = ((b->count * e->probability + REG_BR_PROB_BASE / 2)

gcc/dojump.c

@@ -886,7 +886,6 @@ do_compare_rtx_and_jump (rtx op0, rtx op1, enum rtx_code code, int unsignedp,
 {
   rtx tem;
   rtx dummy_label = NULL_RTX;
-  rtx last;
 
   /* Reverse the comparison if that is safe and we want to jump if it is
      false.  Also convert to the reverse comparison if the target can
@@ -1069,25 +1068,8 @@ do_compare_rtx_and_jump (rtx op0, rtx op1, enum rtx_code code, int unsignedp,
 	    }
 	}
 
-      last = get_last_insn ();
       emit_cmp_and_jump_insns (op0, op1, code, size, mode, unsignedp,
-			       if_true_label);
-      if (prob != -1 && profile_status != PROFILE_ABSENT)
-	{
-	  for (last = NEXT_INSN (last);
-	       last && NEXT_INSN (last);
-	       last = NEXT_INSN (last))
-	    if (JUMP_P (last))
-	      break;
-	  if (last
-	      && JUMP_P (last)
-	      && ! NEXT_INSN (last)
-	      && any_condjump_p (last))
-	    {
-	      gcc_assert (!find_reg_note (last, REG_BR_PROB, 0));
-	      add_reg_note (last, REG_BR_PROB, GEN_INT (prob));
-	    }
-	}
+			       if_true_label, prob);
     }
 
   if (if_false_label)

gcc/except.c

@@ -1161,13 +1161,7 @@ sjlj_emit_function_enter (rtx dispatch_label)
 
       emit_cmp_and_jump_insns (x, const0_rtx, NE, 0,
 			       TYPE_MODE (integer_type_node), 0,
-			       dispatch_label);
-      last = get_last_insn ();
-      if (JUMP_P (last) && any_condjump_p (last))
-	{
-	  gcc_assert (!find_reg_note (last, REG_BR_PROB, 0));
-	  add_reg_note (last, REG_BR_PROB, GEN_INT (REG_BR_PROB_BASE / 100));
-	}
+			       dispatch_label, REG_BR_PROB_BASE / 100);
 #else
       expand_builtin_setjmp_setup (plus_constant (Pmode, XEXP (fc, 0),
 						  sjlj_fc_jbuf_ofs),

gcc/expr.c

@@ -154,7 +154,7 @@ static rtx do_store_flag (sepops, rtx, enum machine_mode);
 #ifdef PUSH_ROUNDING
 static void emit_single_push_insn (enum machine_mode, rtx, tree);
 #endif
-static void do_tablejump (rtx, enum machine_mode, rtx, rtx, rtx);
+static void do_tablejump (rtx, enum machine_mode, rtx, rtx, rtx, int);
 static rtx const_vector_from_tree (tree);
 static void write_complex_part (rtx, rtx, bool);
 
@@ -1483,7 +1483,7 @@ emit_block_move_via_loop (rtx x, rtx y, rtx size,
   emit_label (cmp_label);
 
   emit_cmp_and_jump_insns (iter, size, LT, NULL_RTX, iter_mode,
-			   true, top_label);
+			   true, top_label, REG_BR_PROB_BASE * 90 / 100);
 }
 
 /* Copy all or part of a value X into registers starting at REGNO.
@@ -10824,10 +10824,14 @@ do_store_flag (sepops ops, rtx target, enum machine_mode mode)
 #endif
 
 /* Attempt to generate a casesi instruction.  Returns 1 if successful,
-   0 otherwise (i.e. if there is no casesi instruction).  */
+   0 otherwise (i.e. if there is no casesi instruction).
+
+   DEFAULT_PROBABILITY is the probability of jumping to the default
+   label.  */
 int
 try_casesi (tree index_type, tree index_expr, tree minval, tree range,
-	    rtx table_label, rtx default_label, rtx fallback_label)
+	    rtx table_label, rtx default_label, rtx fallback_label,
+            int default_probability)
 {
   struct expand_operand ops[5];
   enum machine_mode index_mode = SImode;
@@ -10849,7 +10853,8 @@ try_casesi (tree index_type, tree index_expr, tree minval, tree range,
       index = expand_normal (index_expr);
       if (default_label)
         emit_cmp_and_jump_insns (rangertx, index, LTU, NULL_RTX,
-				 omode, 1, default_label);
+				 omode, 1, default_label,
+                                 default_probability);
       /* Now we can safely truncate.  */
       index = convert_to_mode (index_mode, index, 0);
     }
@@ -10895,11 +10900,13 @@ try_casesi (tree index_type, tree index_expr, tree minval, tree range,
    TABLE_LABEL is a CODE_LABEL rtx for the table itself.
 
    DEFAULT_LABEL is a CODE_LABEL rtx to jump to if the
-   index value is out of range.  */
+   index value is out of range.
+   DEFAULT_PROBABILITY is the probability of jumping to
+   the default label.  */
 
 static void
 do_tablejump (rtx index, enum machine_mode mode, rtx range, rtx table_label,
-	      rtx default_label)
+	      rtx default_label, int default_probability)
 {
   rtx temp, vector;
 
@@ -10916,7 +10923,8 @@ do_tablejump (rtx index, enum machine_mode mode, rtx range, rtx table_label,
 
   if (default_label)
     emit_cmp_and_jump_insns (index, range, GTU, NULL_RTX, mode, 1,
-			     default_label);
+			     default_label, default_probability);
+
 
   /* If index is in range, it must fit in Pmode.
      Convert to Pmode so we can index with it.  */
@@ -10959,7 +10967,7 @@ do_tablejump (rtx index, enum machine_mode mode, rtx range, rtx table_label,
 
 int
 try_tablejump (tree index_type, tree index_expr, tree minval, tree range,
-	       rtx table_label, rtx default_label)
+	       rtx table_label, rtx default_label, int default_probability)
 {
   rtx index;
 
@@ -10977,7 +10985,7 @@ try_tablejump (tree index_type, tree index_expr, tree minval, tree range,
 			       TYPE_MODE (TREE_TYPE (range)),
 			       expand_normal (range),
 			       TYPE_UNSIGNED (TREE_TYPE (range))),
-		table_label, default_label);
+		table_label, default_label, default_probability);
   return 1;
 }
 

gcc/expr.h

@@ -190,7 +190,7 @@ extern int have_sub2_insn (rtx, rtx);
 /* Emit a pair of rtl insns to compare two rtx's and to jump
    to a label if the comparison is true.  */
 extern void emit_cmp_and_jump_insns (rtx, rtx, enum rtx_code, rtx,
-				     enum machine_mode, int, rtx);
+				     enum machine_mode, int, rtx, int prob=-1);
 
 /* Generate code to indirectly jump to a location given in the rtx LOC.  */
 extern void emit_indirect_jump (rtx);
@@ -485,8 +485,8 @@ extern void do_compare_rtx_and_jump (rtx, rtx, enum rtx_code, int,
 				     enum machine_mode, rtx, rtx, rtx, int);
 
 /* Two different ways of generating switch statements.  */
-extern int try_casesi (tree, tree, tree, tree, rtx, rtx, rtx);
-extern int try_tablejump (tree, tree, tree, tree, rtx, rtx);
+extern int try_casesi (tree, tree, tree, tree, rtx, rtx, rtx, int);
+extern int try_tablejump (tree, tree, tree, tree, rtx, rtx, int);
 
 /* Functions from alias.c */
 #include "alias.h"

gcc/optabs.c

@@ -4249,11 +4249,12 @@ prepare_operand (enum insn_code icode, rtx x, int opnum, enum machine_mode mode,
    we can do the branch.  */
 
 static void
-emit_cmp_and_jump_insn_1 (rtx test, enum machine_mode mode, rtx label)
+emit_cmp_and_jump_insn_1 (rtx test, enum machine_mode mode, rtx label, int prob)
 {
   enum machine_mode optab_mode;
   enum mode_class mclass;
   enum insn_code icode;
+  rtx insn;
 
   mclass = GET_MODE_CLASS (mode);
   optab_mode = (mclass == MODE_CC) ? CCmode : mode;
@@ -4261,7 +4262,17 @@ emit_cmp_and_jump_insn_1 (rtx test, enum machine_mode mode, rtx label)
 
   gcc_assert (icode != CODE_FOR_nothing);
   gcc_assert (insn_operand_matches (icode, 0, test));
-  emit_jump_insn (GEN_FCN (icode) (test, XEXP (test, 0), XEXP (test, 1), label));
+  insn = emit_jump_insn (GEN_FCN (icode) (test, XEXP (test, 0),
+                                          XEXP (test, 1), label));
+  if (prob != -1
+      && profile_status != PROFILE_ABSENT
+      && insn
+      && JUMP_P (insn)
+      && any_condjump_p (insn))
+    {
+      gcc_assert (!find_reg_note (insn, REG_BR_PROB, 0));
+      add_reg_note (insn, REG_BR_PROB, GEN_INT (prob));
+    }
 }
 
 /* Generate code to compare X with Y so that the condition codes are
@@ -4279,11 +4290,14 @@ emit_cmp_and_jump_insn_1 (rtx test, enum machine_mode mode, rtx label)
 
    COMPARISON is the rtl operator to compare with (EQ, NE, GT, etc.).
    It will be potentially converted into an unsigned variant based on
-   UNSIGNEDP to select a proper jump instruction.  */
+   UNSIGNEDP to select a proper jump instruction.
+   
+   PROB is the probability of jumping to LABEL.  */
 
 void
 emit_cmp_and_jump_insns (rtx x, rtx y, enum rtx_code comparison, rtx size,
-			 enum machine_mode mode, int unsignedp, rtx label)
+			 enum machine_mode mode, int unsignedp, rtx label,
+                         int prob)
 {
   rtx op0 = x, op1 = y;
   rtx test;
@@ -4307,7 +4321,7 @@ emit_cmp_and_jump_insns (rtx x, rtx y, enum rtx_code comparison, rtx size,
 
   prepare_cmp_insn (op0, op1, comparison, size, unsignedp, OPTAB_LIB_WIDEN,
 		    &test, &mode);
-  emit_cmp_and_jump_insn_1 (test, mode, label);
+  emit_cmp_and_jump_insn_1 (test, mode, label, prob);
 }
 
 
@@ -6952,9 +6966,9 @@ expand_compare_and_swap_loop (rtx mem, rtx old_reg, rtx new_reg, rtx seq)
   if (oldval != cmp_reg)
     emit_move_insn (cmp_reg, oldval);
 
-  /* ??? Mark this jump predicted not taken?  */
+  /* Mark this jump predicted not taken.  */
   emit_cmp_and_jump_insns (success, const0_rtx, EQ, const0_rtx,
-			   GET_MODE (success), 1, label);
+			   GET_MODE (success), 1, label, 0);
   return true;
 }
 

gcc/testsuite/ChangeLog

+2012-10-15   Easwaran Raman  <eraman@google.com>
+	* gcc.dg/tree-prof/switch-case-1.c: New test case.
+	* gcc.dg/tree-prof/switch-case-2.c: New test case.
+
 2012-10-16  Hans-Peter Nilsson  <hp@bitrange.com>
 
 	* gcc.dg/torture/stackalign/builtin-apply-2.c,

gcc/testsuite/gcc.dg/tree-prof/switch-case-1.c

+/* { dg-options "-O2 -fdump-rtl-expand-all" } */
+int g;
+
+__attribute__((noinline)) void foo (int  n)
+{
+  switch (n)
+    {
+    case 1:
+      g++; break;
+    case 2:
+      g += 2; break;
+    case 3:
+      g += 1; break;
+    case 4:
+      g += 3; break;
+    case 5:
+      g += 4; break;
+    case 6:
+      g += 5; break;
+    case 7:
+      g += 6; break;
+    case 8:
+      g += 7; break;
+    case 9:
+      g += 8; break;
+    default:
+      g += 8; break;
+   }
+}
+
+int main ()
+{
+ int i;
+ for (i = 0; i < 10000; i++)
+   foo ((i * i) % 5);
+ return 0;
+}
+/* { dg-final-use { scan-rtl-dump-times ";; basic block\[^\\n\]*count 4000" 2 "expand"} } */
+/* { dg-final-use { scan-rtl-dump-times ";; basic block\[^\\n\]*count 2000" 1 "expand"} } */
+/* { dg-final-use { cleanup-rtl-dump "expand" } } */

gcc/testsuite/gcc.dg/tree-prof/switch-case-2.c

+/* { dg-options "-O2 -fdump-rtl-expand-all" } */
+int g;
+
+__attribute__((noinline)) void foo (int  n)
+{
+  switch (n)
+    {
+    case 99:
+      g += 2; break;
+    case 1:
+      g++; break;
+    case 100:
+      g += 1; break;
+    case 4:
+      g += 3; break;
+    case 5:
+      g += 4; break;
+    case 6:
+      g += 5; break;
+    case 7:
+      g += 6; break;
+    case 8:
+      g += 7; break;
+    case 9:
+      g += 8; break;
+    default:
+      g += 8; break;
+   }
+}
+
+int main ()
+{
+ int i;
+ for (i = 0; i < 10000; i++)
+   foo ((i * i) % 5);
+ return 0;
+}
+/* { dg-final-use { scan-rtl-dump-times ";; basic block\[^\\n\]*count 4000" 2 "expand"} } */
+/* { dg-final-use { scan-rtl-dump-times ";; basic block\[^\\n\]*count 2000" 1 "expand"} } */
+/* { dg-final-use { cleanup-rtl-dump "expand" } } */