2010-01-05 Alexandre Oliva * params.def (PARAM_MAX_VARTRACK_SIZE): New. * doc/invoke.texi: Document it. * var-tracking.c: Include toplev.h and params.h. (vt_find_locations): Return bool indicating success. Compute hash sizes unconditionally. Check new parameter, report. (variable_tracking_main_1): Check vt_find_locations results and retry. Renamed from... (variable_tracking_main): ... this. New wrapper to preserve flag_var_tracking_assignments. * Makefile.in (var-tracking.o): Adjust dependencies. --- gcc/doc/invoke.texi.jj 2010-01-09 20:39:58.000000000 +0100 +++ gcc/doc/invoke.texi 2010-01-21 10:00:15.979730377 +0100 @@ -7937,6 +7937,15 @@ with more basic blocks than this paramet motion optimization performed on them. The default value of the parameter is 1000 for -O1 and 10000 for -O2 and above. +@item max-vartrack-size +Sets a maximum number of hash table slots to use during variable +tracking dataflow analysis of any function. If this limit is exceeded +with variable tracking at assignments enabled, analysis for that +function is retried without it, after removing all debug insns from +the function. If the limit is exceeded even without debug insns, var +tracking analysis is completely disabled for the function. Setting +the parameter to zero makes it unlimited. + @item min-nondebug-insn-uid Use uids starting at this parameter for nondebug insns. The range below the parameter is reserved exclusively for debug insns created by --- gcc/params.def.jj 2010-01-09 20:39:58.000000000 +0100 +++ gcc/params.def 2010-01-21 10:00:15.980730943 +0100 @@ -771,6 +771,13 @@ DEFPARAM (PARAM_LOOP_INVARIANT_MAX_BBS_I "max basic blocks number in loop for loop invariant motion", 10000, 0, 0) +/* Set maximum hash table size for var tracking. */ + +DEFPARAM (PARAM_MAX_VARTRACK_SIZE, + "max-vartrack-size", + "Max. size of var tracking hash tables", + 50000000, 0, 0) + /* Set minimum insn uid for non-debug insns. */ DEFPARAM (PARAM_MIN_NONDEBUG_INSN_UID, --- gcc/var-tracking.c.jj 2010-01-21 09:10:37.000000000 +0100 +++ gcc/var-tracking.c 2010-01-21 10:00:15.983740989 +0100 @@ -109,6 +109,8 @@ #include "tree-flow.h" #include "cselib.h" #include "target.h" +#include "toplev.h" +#include "params.h" /* var-tracking.c assumes that tree code with the same value as VALUE rtx code has no chance to appear in REG_EXPR/MEM_EXPRs and isn't a decl. @@ -451,7 +453,7 @@ static int add_uses (rtx *, void *); static void add_uses_1 (rtx *, void *); static void add_stores (rtx, const_rtx, void *); static bool compute_bb_dataflow (basic_block); -static void vt_find_locations (void); +static bool vt_find_locations (void); static void dump_attrs_list (attrs); static int dump_var_slot (void **, void *); @@ -5511,7 +5513,7 @@ compute_bb_dataflow (basic_block bb) /* Find the locations of variables in the whole function. */ -static void +static bool vt_find_locations (void) { fibheap_t worklist, pending, fibheap_swap; @@ -5522,6 +5524,8 @@ vt_find_locations (void) int *rc_order; int i; int htabsz = 0; + int htabmax = PARAM_VALUE (PARAM_MAX_VARTRACK_SIZE); + bool success = true; /* Compute reverse completion order of depth first search of the CFG so that the data-flow runs faster. */ @@ -5543,7 +5547,7 @@ vt_find_locations (void) fibheap_insert (pending, bb_order[bb->index], bb); sbitmap_ones (in_pending); - while (!fibheap_empty (pending)) + while (success && !fibheap_empty (pending)) { fibheap_swap = pending; pending = worklist; @@ -5566,11 +5570,11 @@ vt_find_locations (void) SET_BIT (visited, bb->index); - if (dump_file && VTI (bb)->in.vars) + if (VTI (bb)->in.vars) { htabsz - -= htab_size (shared_hash_htab (VTI (bb)->in.vars)) - + htab_size (shared_hash_htab (VTI (bb)->out.vars)); + -= (htab_size (shared_hash_htab (VTI (bb)->in.vars)) + + htab_size (shared_hash_htab (VTI (bb)->out.vars))); oldinsz = htab_elements (shared_hash_htab (VTI (bb)->in.vars)); oldoutsz @@ -5634,9 +5638,20 @@ vt_find_locations (void) } changed = compute_bb_dataflow (bb); - if (dump_file) - htabsz += htab_size (shared_hash_htab (VTI (bb)->in.vars)) - + htab_size (shared_hash_htab (VTI (bb)->out.vars)); + htabsz += (htab_size (shared_hash_htab (VTI (bb)->in.vars)) + + htab_size (shared_hash_htab (VTI (bb)->out.vars))); + + if (htabmax && htabsz > htabmax) + { + if (MAY_HAVE_DEBUG_INSNS) + inform (DECL_SOURCE_LOCATION (cfun->decl), + "variable tracking size limit exceeded with debug insns, retrying without"); + else + inform (DECL_SOURCE_LOCATION (cfun->decl), + "variable tracking size limit exceeded"); + success = false; + break; + } if (changed) { @@ -5687,7 +5702,7 @@ vt_find_locations (void) } } - if (MAY_HAVE_DEBUG_INSNS) + if (success && MAY_HAVE_DEBUG_INSNS) FOR_EACH_BB (bb) gcc_assert (VTI (bb)->flooded); @@ -5698,6 +5713,8 @@ vt_find_locations (void) sbitmap_free (visited); sbitmap_free (in_worklist); sbitmap_free (in_pending); + + return success; } /* Print the content of the LIST to dump file. */ @@ -7600,9 +7617,11 @@ vt_finalize (void) /* The entry point to variable tracking pass. */ -unsigned int -variable_tracking_main (void) +static inline unsigned int +variable_tracking_main_1 (void) { + bool success; + if (flag_var_tracking_assignments < 0) { delete_debug_insns (); @@ -7627,7 +7646,31 @@ variable_tracking_main (void) } } - vt_find_locations (); + success = vt_find_locations (); + + if (!success && flag_var_tracking_assignments > 0) + { + vt_finalize (); + + delete_debug_insns (); + + /* This is later restored by our caller. */ + flag_var_tracking_assignments = 0; + + vt_initialize (); + + if (!frame_pointer_needed && !vt_stack_adjustments ()) + gcc_unreachable (); + + success = vt_find_locations (); + } + + if (!success) + { + vt_finalize (); + vt_debug_insns_local (false); + return 0; + } if (dump_file && (dump_flags & TDF_DETAILS)) { @@ -7641,6 +7684,19 @@ variable_tracking_main (void) vt_debug_insns_local (false); return 0; } + +unsigned int +variable_tracking_main (void) +{ + unsigned int ret; + int save = flag_var_tracking_assignments; + + ret = variable_tracking_main_1 (); + + flag_var_tracking_assignments = save; + + return ret; +} static bool gate_handle_var_tracking (void) --- gcc/Makefile.in.jj 2010-01-21 08:58:12.000000000 +0100 +++ gcc/Makefile.in 2010-01-21 10:00:45.555730868 +0100 @@ -2751,7 +2751,7 @@ var-tracking.o : var-tracking.c $(CONFIG $(RTL_H) $(TREE_H) hard-reg-set.h insn-config.h reload.h $(FLAGS_H) \ $(BASIC_BLOCK_H) output.h sbitmap.h alloc-pool.h $(FIBHEAP_H) $(HASHTAB_H) \ $(REGS_H) $(EXPR_H) $(TIMEVAR_H) tree-pass.h cselib.h $(TARGET_H) \ - $(TREE_FLOW_H) + $(TREE_FLOW_H) $(TOPLEV_H) $(PARAMS_H) profile.o : profile.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) $(RTL_H) \ $(TREE_H) $(FLAGS_H) output.h $(REGS_H) $(EXPR_H) $(FUNCTION_H) \ $(TOPLEV_H) $(COVERAGE_H) $(TREE_FLOW_H) value-prof.h cfghooks.h \