From: Jan Hubicka Date: Tue, 9 Oct 2007 07:07:15 +0000 (+0200) Subject: invoke.texi (align-threshold, [...]): Document. X-Git-Tag: releases/gcc-4.3.0~2147 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=edbed3d31e8f6981f4bf4692c132b95081ab5112;p=thirdparty%2Fgcc.git invoke.texi (align-threshold, [...]): Document. * invoke.texi (align-threshold, align-loop-iterations): Document. * final.c: Include cfgloop.h, params.h (compute_alignments): Dump decisions and compare them with loop structure; honor given parameters. (pass_compute_alignments): New dump file. * params.def (PARAM_ALIGN_THRESHOLD, PARAM_ALIGN_LOOP_ITERATIONS): New. * Makefile.in (final.o): Add dependency on cfgloop.h and params.h From-SVN: r129162 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 03230d1eebe3..4717ca8a4b0e 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,13 @@ +2007-10-09 Jan Hubicka + + * invoke.texi (align-threshold, align-loop-iterations): Document. + * final.c: Include cfgloop.h, params.h + (compute_alignments): Dump decisions and compare them with loop + structure; honor given parameters. + (pass_compute_alignments): New dump file. + * params.def (PARAM_ALIGN_THRESHOLD, PARAM_ALIGN_LOOP_ITERATIONS): New. + * Makefile.in (final.o): Add dependency on cfgloop.h and params.h + 2007-10-09 James E. Wilson PR tree-optimization/33655 diff --git a/gcc/Makefile.in b/gcc/Makefile.in index c31b25916a78..5aee30e42baa 100644 --- a/gcc/Makefile.in +++ b/gcc/Makefile.in @@ -2803,7 +2803,8 @@ final.o : final.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) $(RTL_H) \ insn-config.h $(INSN_ATTR_H) $(FUNCTION_H) output.h hard-reg-set.h \ except.h debug.h xcoffout.h toplev.h reload.h dwarf2out.h tree-pass.h \ $(BASIC_BLOCK_H) $(TM_P_H) $(TARGET_H) $(EXPR_H) $(CFGLAYOUT_H) dbxout.h \ - $(TIMEVAR_H) $(CGRAPH_H) $(COVERAGE_H) $(REAL_H) $(DF_H) vecprim.h $(GGC_H) + $(TIMEVAR_H) $(CGRAPH_H) $(COVERAGE_H) $(REAL_H) $(DF_H) vecprim.h $(GGC_H) \ + $(CFGLOOP_H) $(PARAMS_H) recog.o : recog.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) $(RTL_H) \ $(FUNCTION_H) $(BASIC_BLOCK_H) $(REGS_H) $(RECOG_H) $(EXPR_H) \ $(FLAGS_H) insn-config.h $(INSN_ATTR_H) toplev.h output.h reload.h \ diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index ab7da0fd1670..e5318eb2f260 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -6873,6 +6873,16 @@ with unknown. We predict the known number of iterations correctly, while the unknown number of iterations average to roughly 10. This means that the loop without bounds would appear artificially cold relative to the other one. +@item align-threshold + +Select fraction of the maximal frequency of executions of basic block in +function given basic block will get aligned. + +@item align-loop-iterations + +A loop expected to iterate at lest the selected number of iterations will get +aligned. + @item tracer-dynamic-coverage @itemx tracer-dynamic-coverage-feedback diff --git a/gcc/final.c b/gcc/final.c index b59a22200113..654f847c5e30 100644 --- a/gcc/final.c +++ b/gcc/final.c @@ -78,6 +78,8 @@ along with GCC; see the file COPYING3. If not see #include "df.h" #include "vecprim.h" #include "ggc.h" +#include "cfgloop.h" +#include "params.h" #ifdef XCOFF_DEBUGGING_INFO #include "xcoffout.h" /* Needed for external data @@ -673,6 +675,8 @@ compute_alignments (void) { int log, max_skip, max_log; basic_block bb; + int freq_max = 0; + int freq_threshold = 0; if (label_align) { @@ -688,6 +692,19 @@ compute_alignments (void) if (! optimize || optimize_size) return 0; + if (dump_file) + { + dump_flow_info (dump_file, TDF_DETAILS); + flow_loops_dump (dump_file, NULL, 1); + loop_optimizer_init (AVOID_CFG_MODIFICATIONS); + } + FOR_EACH_BB (bb) + if (bb->frequency > freq_max) + freq_max = bb->frequency; + freq_threshold = freq_max / PARAM_VALUE (PARAM_ALIGN_THRESHOLD); + + if (dump_file) + fprintf(dump_file, "freq_max: %i\n",freq_max); FOR_EACH_BB (bb) { rtx label = BB_HEAD (bb); @@ -697,7 +714,12 @@ compute_alignments (void) if (!LABEL_P (label) || probably_never_executed_bb_p (bb)) - continue; + { + if (dump_file) + fprintf(dump_file, "BB %4i freq %4i loop %2i loop_depth %2i skipped.\n", + bb->index, bb->frequency, bb->loop_father->num, bb->loop_depth); + continue; + } max_log = LABEL_ALIGN (label); max_skip = LABEL_ALIGN_MAX_SKIP; @@ -708,6 +730,18 @@ compute_alignments (void) else branch_frequency += EDGE_FREQUENCY (e); } + if (dump_file) + { + fprintf(dump_file, "BB %4i freq %4i loop %2i loop_depth %2i fall %4i branch %4i", + bb->index, bb->frequency, bb->loop_father->num, + bb->loop_depth, + fallthru_frequency, branch_frequency); + if (!bb->loop_father->inner && bb->loop_father->num) + fprintf (dump_file, " inner_loop"); + if (bb->loop_father->header == bb) + fprintf (dump_file, " loop_header"); + fprintf (dump_file, "\n"); + } /* There are two purposes to align block with no fallthru incoming edge: 1) to avoid fetch stalls when branch destination is near cache boundary @@ -720,12 +754,14 @@ compute_alignments (void) when function is called. */ if (!has_fallthru - && (branch_frequency > BB_FREQ_MAX / 10 + && (branch_frequency > freq_threshold || (bb->frequency > bb->prev_bb->frequency * 10 && (bb->prev_bb->frequency <= ENTRY_BLOCK_PTR->frequency / 2)))) { log = JUMP_ALIGN (label); + if (dump_file) + fprintf(dump_file, " jump alignment added.\n"); if (max_log < log) { max_log = log; @@ -736,10 +772,13 @@ compute_alignments (void) align it. It is most likely a first block of loop. */ if (has_fallthru && maybe_hot_bb_p (bb) - && branch_frequency + fallthru_frequency > BB_FREQ_MAX / 10 - && branch_frequency > fallthru_frequency * 2) + && branch_frequency + fallthru_frequency > freq_threshold + && (branch_frequency + > fallthru_frequency * PARAM_VALUE (PARAM_ALIGN_LOOP_ITERATIONS))) { log = LOOP_ALIGN (label); + if (dump_file) + fprintf(dump_file, " internal loop alignment added.\n"); if (max_log < log) { max_log = log; @@ -749,12 +788,15 @@ compute_alignments (void) LABEL_TO_ALIGNMENT (label) = max_log; LABEL_TO_MAX_SKIP (label) = max_skip; } + + if (dump_file) + loop_optimizer_finalize (); return 0; } struct tree_opt_pass pass_compute_alignments = { - NULL, /* name */ + "alignments", /* name */ NULL, /* gate */ compute_alignments, /* execute */ NULL, /* sub */ @@ -765,7 +807,8 @@ struct tree_opt_pass pass_compute_alignments = 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ - 0, /* todo_flags_finish */ + TODO_dump_func | TODO_verify_rtl_sharing + | TODO_ggc_collect, /* todo_flags_finish */ 0 /* letter */ }; diff --git a/gcc/params.def b/gcc/params.def index c9ae99bd6880..5cb1f6da7c2d 100644 --- a/gcc/params.def +++ b/gcc/params.def @@ -334,6 +334,16 @@ DEFPARAM(HOT_BB_FREQUENCY_FRACTION, "Select fraction of the maximal frequency of executions of basic block in function given basic block needs to have to be considered hot", 1000, 0, 0) +DEFPARAM (PARAM_ALIGN_THRESHOLD, + "align-threshold", + "Select fraction of the maximal frequency of executions of basic block in function given basic block get alignment", + 100, 0, 0) + +DEFPARAM (PARAM_ALIGN_LOOP_ITERATIONS, + "align-loop-iterations", + "Loops iterating at least selected number of iterations will get loop alignement.", + 4, 0, 0) + /* For guessed profiles, the loops having unknown number of iterations are predicted to iterate relatively few (10) times at average. For functions containing one loop with large known number of iterations