-/* This file contains the definitions and documentation for the
- builtins used in the GNU compiler.
- Copyright (C) 2001 Free Software Foundation, Inc.
+/* Definitions for the branch prediction routines in the GNU compiler.
+ Copyright (C) 2001, 2003, 2004, 2007 Free Software Foundation, Inc.
-This file is part of GNU CC.
+This file is part of GCC.
-GNU CC is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
-any later version.
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
-GNU CC is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
You should have received a copy of the GNU General Public License
-along with GNU CC; see the file COPYING. If not, write to
-the Free Software Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
/* Before including this file, you should define a macro:
REG_BR_PROB_BASE / 2). */
-DEF_PREDICTOR (PRED_FIRST_MATCH, "first match", PROB_ALWAYS)
-DEF_PREDICTOR (PRED_UNCONDITIONAL, "unconditional jump", PROB_ALWAYS)
-DEF_PREDICTOR (PRED_BUILTIN_EXPECT, "__builtin_expect", PROB_VERY_LIKELY)
-DEF_PREDICTOR (PRED_NORETURN, "noreturn call", PROB_ALWAYS)
-DEF_PREDICTOR (PRED_LOOP_BRANCH, "loop branch", PROB_VERY_LIKELY)
-DEF_PREDICTOR (PRED_LOOP_EXIT, "loop exit", PROB_LIKELY)
-DEF_PREDICTOR (PRED_LOOP_HEADER, "loop header", PROB_LIKELY)
-DEF_PREDICTOR (PRED_POINTER, "pointer", PROB_LIKELY)
-DEF_PREDICTOR (PRED_OPCODE, "opcode", PROB_LIKELY)
+/* A value used as final outcome of all heuristics. */
+DEF_PREDICTOR (PRED_COMBINED, "combined", PROB_ALWAYS, 0)
+
+/* An outcome estimated by Dempster-Shaffer theory. */
+DEF_PREDICTOR (PRED_DS_THEORY, "DS theory", PROB_ALWAYS, 0)
+
+/* A combined heuristics using probability determined by first
+ matching heuristics from this list. */
+DEF_PREDICTOR (PRED_FIRST_MATCH, "first match", PROB_ALWAYS, 0)
+
+/* Heuristic applying when no heuristic below applies. */
+DEF_PREDICTOR (PRED_NO_PREDICTION, "no prediction", PROB_ALWAYS, 0)
+
+/* Mark unconditional jump as taken. */
+DEF_PREDICTOR (PRED_UNCONDITIONAL, "unconditional jump", PROB_ALWAYS,
+ PRED_FLAG_FIRST_MATCH)
+
+/* Use number of loop iterations determined by # of iterations
+ analysis to set probability. We don't want to use Dempster-Shaffer
+ theory here, as the predictions is exact. */
+DEF_PREDICTOR (PRED_LOOP_ITERATIONS, "loop iterations", PROB_ALWAYS,
+ PRED_FLAG_FIRST_MATCH)
+
+/* Hints dropped by user via __builtin_expect feature. */
+DEF_PREDICTOR (PRED_BUILTIN_EXPECT, "__builtin_expect", PROB_VERY_LIKELY,
+ PRED_FLAG_FIRST_MATCH)
+
+/* Use number of loop iterations guessed by the contents of the loop. */
+DEF_PREDICTOR (PRED_LOOP_ITERATIONS_GUESSED, "guessed loop iterations",
+ PROB_ALWAYS, PRED_FLAG_FIRST_MATCH)
+
+/* Branch containing goto is probably not taken. */
+DEF_PREDICTOR (PRED_CONTINUE, "continue", HITRATE (56), 0)
+
+/* Branch to basic block containing call marked by noreturn attribute. */
+DEF_PREDICTOR (PRED_NORETURN, "noreturn call", HITRATE (99),
+ PRED_FLAG_FIRST_MATCH)
+
+/* Branch to basic block containing call marked by cold function attribute. */
+DEF_PREDICTOR (PRED_COLD_FUNCTION, "cold function call", HITRATE (99),
+ PRED_FLAG_FIRST_MATCH)
+
+/* Loopback edge is taken. */
+DEF_PREDICTOR (PRED_LOOP_BRANCH, "loop branch", HITRATE (86),
+ PRED_FLAG_FIRST_MATCH)
+
+/* Edge causing loop to terminate is probably not taken. */
+DEF_PREDICTOR (PRED_LOOP_EXIT, "loop exit", HITRATE (91),
+ PRED_FLAG_FIRST_MATCH)
+
+/* Pointers are usually not NULL. */
+DEF_PREDICTOR (PRED_POINTER, "pointer", HITRATE (85), 0)
+DEF_PREDICTOR (PRED_TREE_POINTER, "pointer (on trees)", HITRATE (85), 0)
+
+/* NE is probable, EQ not etc... */
+DEF_PREDICTOR (PRED_OPCODE_POSITIVE, "opcode values positive", HITRATE (79), 0)
+DEF_PREDICTOR (PRED_OPCODE_NONEQUAL, "opcode values nonequal", HITRATE (71), 0)
+DEF_PREDICTOR (PRED_FPOPCODE, "fp_opcode", HITRATE (90), 0)
+DEF_PREDICTOR (PRED_TREE_OPCODE_POSITIVE, "opcode values positive (on trees)", HITRATE (73), 0)
+DEF_PREDICTOR (PRED_TREE_OPCODE_NONEQUAL, "opcode values nonequal (on trees)", HITRATE (72), 0)
+DEF_PREDICTOR (PRED_TREE_FPOPCODE, "fp_opcode (on trees)", HITRATE (90), 0)
+
+/* Branch guarding call is probably taken. */
+DEF_PREDICTOR (PRED_CALL, "call", HITRATE (71), 0)
+
+/* Branch causing function to terminate is probably not taken. */
+DEF_PREDICTOR (PRED_TREE_EARLY_RETURN, "early return (on trees)", HITRATE (61), 0)
+
+/* Branch containing goto is probably not taken. */
+DEF_PREDICTOR (PRED_GOTO, "goto", HITRATE (70), 0)
+
+/* Branch ending with return constant is probably not taken. */
+DEF_PREDICTOR (PRED_CONST_RETURN, "const return", HITRATE (67), 0)
+
+/* Branch ending with return negative constant is probably not taken. */
+DEF_PREDICTOR (PRED_NEGATIVE_RETURN, "negative return", HITRATE (96), 0)
+
+/* Branch ending with return; is probably not taken */
+DEF_PREDICTOR (PRED_NULL_RETURN, "null return", HITRATE (90), 0)
+
+/* Branches to a mudflap bounds check are extremely unlikely. */
+DEF_PREDICTOR (PRED_MUDFLAP, "mudflap check", PROB_VERY_LIKELY, 0)
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