6ad48e84df
* predict.c (struct block_info_def): Remove nvisited. (propagate_freq): Use EDGE_DFS_BACK to detect irreducible regions. (estimate_bb_frequencies): Call mark_dfs_back_edges. * i386.c (ix86_agi_depdendant): Lea causes AGI only on the Pentium (ix86_adjust_cost): Teach scheduler that latency to load operand can be masked. From-SVN: r44921
99 lines
3.9 KiB
Modula-2
99 lines
3.9 KiB
Modula-2
/* This file contains the definitions and documentation for the
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builtins used in the GNU compiler.
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Copyright (C) 2001 Free Software Foundation, Inc.
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This file is part of GNU CC.
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GNU CC is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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GNU CC is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GNU CC; see the file COPYING. If not, write to
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the Free Software Foundation, 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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/* Before including this file, you should define a macro:
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DEF_PREDICTOR (ENUM, NAME, HITRATE)
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This macro will be called once for each predictor. The ENUM will
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be of type `enum predictor', and will enumerate all supported
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predictors. The order of DEF_PREDICTOR calls is important, as
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in the first match combining heuristics, the predictor appearing
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first in this file will win.
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NAME is used in the debugging output to determine predictor type.
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HITRATE is the probability that edge predicted by predictor as taken
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will be really taken (so it should be always above
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REG_BR_PROB_BASE / 2). */
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/* A value used as final outcome of all heuristics. */
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DEF_PREDICTOR (PRED_COMBINED, "combined", PROB_ALWAYS, 0)
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/* An outcome estimated by Dempster-Shaffer theory. */
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DEF_PREDICTOR (PRED_DS_THEORY, "DS theory", PROB_ALWAYS, 0)
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/* An combined heuristics using probability determined by first
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matching heuristics from this list. */
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DEF_PREDICTOR (PRED_FIRST_MATCH, "first match", PROB_ALWAYS, 0)
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/* Heuristic applying when no heuristic bellow applies. */
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DEF_PREDICTOR (PRED_NO_PREDICTION, "no prediction", PROB_ALWAYS, 0)
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/* Mark unconditional jump as taken. */
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DEF_PREDICTOR (PRED_UNCONDITIONAL, "unconditional jump", PROB_ALWAYS,
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PRED_FLAG_FIRST_MATCH)
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/* Use number of loop iterations determined by loop unroller to set
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probability. We don't want to use Dempster-Shaffer theory here,
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as the predictions is exact. */
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DEF_PREDICTOR (PRED_LOOP_ITERATIONS, "loop iterations", PROB_ALWAYS,
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PRED_FLAG_FIRST_MATCH)
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/* Hints dropped by user via __builtin_expect feature. */
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DEF_PREDICTOR (PRED_BUILTIN_EXPECT, "__builtin_expect", PROB_VERY_LIKELY,
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PRED_FLAG_FIRST_MATCH)
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/* Branch to basic block containing call marked by noreturn attribute. */
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DEF_PREDICTOR (PRED_NORETURN, "noreturn call", PROB_ALWAYS,
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PRED_FLAG_FIRST_MATCH)
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/* Loopback edge is taken. */
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DEF_PREDICTOR (PRED_LOOP_BRANCH, "loop branch", HITRATE (89),
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PRED_FLAG_FIRST_MATCH)
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/* Edge causing loop to terminate is probably not taken. */
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DEF_PREDICTOR (PRED_LOOP_EXIT, "loop exit", HITRATE (90),
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PRED_FLAG_FIRST_MATCH)
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/* Condition emitted by preconditiong code to ensure that variable
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setting number of iterations is greater than initial value of iterator. */
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DEF_PREDICTOR (PRED_LOOP_CONDITION, "loop condition", PROB_VERY_LIKELY, 0)
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/* Preconditioning makes linear list of branches. */
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DEF_PREDICTOR (PRED_LOOP_PRECONDITIONING, "loop preconditioning", PROB_VERY_LIKELY, 0)
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/* Copied condition for the first iteration of loop is probably true. */
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DEF_PREDICTOR (PRED_LOOP_HEADER, "loop header", HITRATE (64), 0)
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/* Pointers are usually not NULL. */
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DEF_PREDICTOR (PRED_POINTER, "pointer", HITRATE (83), 0)
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/* NE is probable, EQ not etc... */
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DEF_PREDICTOR (PRED_OPCODE, "opcode", HITRATE (55), 0)
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/* Branch guarding call is probably taken. */
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DEF_PREDICTOR (PRED_CALL, "call", HITRATE (70), 0)
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/* Branch causing function to terminate is probably not taken. */
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DEF_PREDICTOR (PRED_ERROR_RETURN, "error return", PROB_LIKELY, 0)
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