Mercurial > hg > CbC > CbC_gcc
diff gcc/df-core.c @ 55:77e2b8dfacca gcc-4.4.5
update it from 4.4.3 to 4.5.0
| author | ryoma <e075725@ie.u-ryukyu.ac.jp> |
|---|---|
| date | Fri, 12 Feb 2010 23:39:51 +0900 |
| parents | a06113de4d67 |
| children | b7f97abdc517 |
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line diff
--- a/gcc/df-core.c Sun Feb 07 18:28:00 2010 +0900 +++ b/gcc/df-core.c Fri Feb 12 23:39:51 2010 +0900 @@ -1,7 +1,7 @@ /* Allocation for dataflow support routines. Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, - 2008 Free Software Foundation, Inc. - Originally contributed by Michael P. Hayes + 2008, 2009 Free Software Foundation, Inc. + Originally contributed by Michael P. Hayes (m.hayes@elec.canterbury.ac.nz, mhayes@redhat.com) Major rewrite contributed by Danny Berlin (dberlin@dberlin.org) and Kenneth Zadeck (zadeck@naturalbridge.com). @@ -43,7 +43,7 @@ available whenever dataflow is available. The LR problem finds the areas that can reach a use of a variable, the UR problems finds the areas that can be reached from a definition of a variable. The LIVE -problem finds the intersection of these two areas. +problem finds the intersection of these two areas. There are several optional problems. These can be enabled when they are needed and disabled when they are not needed. @@ -59,7 +59,7 @@ In the middle layer, basic blocks are scanned to produce transfer functions which describe the effects of that block on the global dataflow solution. The transfer functions are only rebuilt if the -some instruction within the block has changed. +some instruction within the block has changed. The top layer is the dataflow solution itself. The dataflow solution is computed by using an efficient iterative solver and the transfer @@ -170,11 +170,6 @@ d) If the pass modifies all of the insns, as does register allocation, it is simply better to rescan the entire function. - e) If the pass uses either non-standard or ancient techniques to - modify insns, automatic detection of the insns that need to be - rescanned may be impractical. Cse and regrename fall into this - category. - 2) Deferred rescanning - Calls to df_insn_rescan, df_notes_rescan, and df_insn_delete do not immediately change the insn but instead make a note that the insn needs to be rescanned. The next call to @@ -182,32 +177,30 @@ cause all of the pending rescans to be processed. This is the technique of choice if either 1a, 1b, or 1c are issues - in the pass. In the case of 1a or 1b, a call to df_remove_problem - (df_chain) should be made before the next call to df_analyze or - df_process_deferred_rescans. + in the pass. In the case of 1a or 1b, a call to df_finish_pass + (either manually or via TODO_df_finish) should be made before the + next call to df_analyze or df_process_deferred_rescans. + + This mode is also used by a few passes that still rely on note_uses, + note_stores and for_each_rtx instead of using the DF data. This + can be said to fall under case 1c. To enable this mode, call df_set_flags (DF_DEFER_INSN_RESCAN). (This mode can be cleared by calling df_clear_flags (DF_DEFER_INSN_RESCAN) but this does not cause the deferred insns to be rescanned. - 3) Total rescanning - In this mode the rescanning is disabled. - However, the df information associated with deleted insn is delete - at the time the insn is deleted. At the end of the pass, a call - must be made to df_insn_rescan_all. This method is used by the - register allocator since it generally changes each insn multiple - times (once for each ref) and does not need to make use of the - updated scanning information. - - It is also currently used by two older passes (cse, and regrename) - which change insns in hard to track ways. It is hoped that this - will be fixed soon since this it is expensive to rescan all of the - insns when only a small number of them have really changed. +3) Total rescanning - In this mode the rescanning is disabled. + Only when insns are deleted is the df information associated with + it also deleted. At the end of the pass, a call must be made to + df_insn_rescan_all. This method is used by the register allocator + since it generally changes each insn multiple times (once for each ref) + and does not need to make use of the updated scanning information. 4) Do it yourself - In this mechanism, the pass updates the insns itself using the low level df primitives. Currently no pass does this, but it has the advantage that it is quite efficient given - that the pass generally has exact knowledge of what it is changing. + that the pass generally has exact knowledge of what it is changing. DATA STRUCTURES @@ -254,7 +247,7 @@ DATA STRUCTURES: -The basic object is a DF_REF (reference) and this may either be a +The basic object is a DF_REF (reference) and this may either be a DEF (definition) or a USE of a register. These are linked into a variety of lists; namely reg-def, reg-use, @@ -298,12 +291,12 @@ 1) References are divided into two categories, REAL and ARTIFICIAL. - REAL refs are associated with instructions. + REAL refs are associated with instructions. ARTIFICIAL refs are associated with basic blocks. The heads of these lists can be accessed by calling df_get_artificial_defs or - df_get_artificial_uses for the particular basic block. - + df_get_artificial_uses for the particular basic block. + Artificial defs and uses occur both at the beginning and ends of blocks. For blocks that area at the destination of eh edges, the @@ -322,14 +315,14 @@ Artificial defs occur at the end of the entry block. These arise from registers that are live at entry to the function. -2) There are three types of refs: defs, uses and eq_uses. (Eq_uses are +2) There are three types of refs: defs, uses and eq_uses. (Eq_uses are uses that appear inside a REG_EQUAL or REG_EQUIV note.) All of the eq_uses, uses and defs associated with each pseudo or hard register may be linked in a bidirectional chain. These are called reg-use or reg_def chains. If the changeable flag DF_EQ_NOTES is set when the chains are built, the eq_uses will be - treated like uses. If it is not set they are ignored. + treated like uses. If it is not set they are ignored. The first use, eq_use or def for a register can be obtained using the DF_REG_USE_CHAIN, DF_REG_EQ_USE_CHAIN or DF_REG_DEF_CHAIN @@ -354,14 +347,14 @@ has been set the array will contain the eq_uses. Otherwise these are ignored when building the array and assigning the ids. Note that the values in the id field of a ref may change across calls to - df_analyze or df_reorganize_defs or df_reorganize_uses. + df_analyze or df_reorganize_defs or df_reorganize_uses. If the only use of this array is to find all of the refs, it is better to traverse all of the registers and then traverse all of reg-use or reg-def chains. NOTES: - + Embedded addressing side-effects, such as POST_INC or PRE_INC, generate both a use and a def. These are both marked read/write to show that they are dependent. For example, (set (reg 40) (mem (post_inc (reg 42)))) @@ -378,7 +371,7 @@ read/write. Paradoxical subreg writes do not leave a trace of the old content, so they -are write-only operations. +are write-only operations. */ @@ -455,7 +448,7 @@ However for this to work, the computation of RI must be pushed after which ever of those problems is defined, but we do not require any of those except for LR to have actually been - defined. */ + defined. */ df->num_problems_defined++; for (i = df->num_problems_defined - 2; i >= 0; i--) { @@ -474,10 +467,10 @@ /* Set the MASK flags in the DFLOW problem. The old flags are returned. If a flag is not allowed to be changed this will fail if checking is enabled. */ -enum df_changeable_flags -df_set_flags (enum df_changeable_flags changeable_flags) +int +df_set_flags (int changeable_flags) { - enum df_changeable_flags old_flags = df->changeable_flags; + int old_flags = df->changeable_flags; df->changeable_flags |= changeable_flags; return old_flags; } @@ -486,10 +479,10 @@ /* Clear the MASK flags in the DFLOW problem. The old flags are returned. If a flag is not allowed to be changed this will fail if checking is enabled. */ -enum df_changeable_flags -df_clear_flags (enum df_changeable_flags changeable_flags) +int +df_clear_flags (int changeable_flags) { - enum df_changeable_flags old_flags = df->changeable_flags; + int old_flags = df->changeable_flags; df->changeable_flags &= ~changeable_flags; return old_flags; } @@ -499,7 +492,7 @@ not called or is called with null, the entire function in analyzed. */ -void +void df_set_blocks (bitmap blocks) { if (blocks) @@ -522,7 +515,7 @@ { bitmap_iterator bi; unsigned int bb_index; - + EXECUTE_IF_SET_IN_BITMAP (diff, 0, bb_index, bi) { basic_block bb = BASIC_BLOCK (bb_index); @@ -559,7 +552,7 @@ BITMAP_ALLOC (&df_bitmap_obstack); FOR_ALL_BB(bb) { - bitmap_set_bit (blocks_to_reset, bb->index); + bitmap_set_bit (blocks_to_reset, bb->index); } } dflow->problem->reset_fun (blocks_to_reset); @@ -736,7 +729,7 @@ gcc_assert (df->n_blocks == df->n_blocks_inverted); df->hard_regs_live_count = XNEWVEC (unsigned int, FIRST_PSEUDO_REGISTER); - memset (df->hard_regs_live_count, 0, + memset (df->hard_regs_live_count, 0, sizeof (unsigned int) * FIRST_PSEUDO_REGISTER); df_hard_reg_init (); @@ -766,7 +759,7 @@ NULL, /* sub */ NULL, /* next */ 0, /* static_pass_number */ - 0, /* tv_id */ + TV_NONE, /* tv_id */ 0, /* properties_required */ 0, /* properties_provided */ 0, /* properties_destroyed */ @@ -787,13 +780,13 @@ { { RTL_PASS, - "dfinit", /* name */ + "no-opt dfinit", /* name */ gate_no_opt, /* gate */ rest_of_handle_df_initialize, /* execute */ NULL, /* sub */ NULL, /* next */ 0, /* static_pass_number */ - 0, /* tv_id */ + TV_NONE, /* tv_id */ 0, /* properties_required */ 0, /* properties_provided */ 0, /* properties_destroyed */ @@ -816,7 +809,7 @@ for (i = 0; i < df->num_problems_defined; i++) { struct dataflow *dflow = df->problems_in_order[i]; - dflow->problem->free_fun (); + dflow->problem->free_fun (); } if (df->postorder) @@ -842,7 +835,7 @@ NULL, /* sub */ NULL, /* next */ 0, /* static_pass_number */ - 0, /* tv_id */ + TV_NONE, /* tv_id */ 0, /* properties_required */ 0, /* properties_provided */ 0, /* properties_destroyed */ @@ -861,7 +854,7 @@ /* Helper function for df_worklist_dataflow. - Propagate the dataflow forward. + Propagate the dataflow forward. Given a BB_INDEX, do the dataflow propagation and set bits on for successors in PENDING if the out set of the dataflow has changed. */ @@ -880,16 +873,16 @@ /* Calculate <conf_op> of incoming edges. */ if (EDGE_COUNT (bb->preds) > 0) FOR_EACH_EDGE (e, ei, bb->preds) - { - if (TEST_BIT (considered, e->src->index)) + { + if (TEST_BIT (considered, e->src->index)) dataflow->problem->con_fun_n (e); - } + } else if (dataflow->problem->con_fun_0) dataflow->problem->con_fun_0 (bb); if (dataflow->problem->trans_fun (bb_index)) { - /* The out set of this block has changed. + /* The out set of this block has changed. Propagate to the outgoing blocks. */ FOR_EACH_EDGE (e, ei, bb->succs) { @@ -919,16 +912,16 @@ /* Calculate <conf_op> of incoming edges. */ if (EDGE_COUNT (bb->succs) > 0) FOR_EACH_EDGE (e, ei, bb->succs) - { - if (TEST_BIT (considered, e->dest->index)) + { + if (TEST_BIT (considered, e->dest->index)) dataflow->problem->con_fun_n (e); - } + } else if (dataflow->problem->con_fun_0) dataflow->problem->con_fun_0 (bb); if (dataflow->problem->trans_fun (bb_index)) { - /* The out set of this block has changed. + /* The out set of this block has changed. Propagate to the outgoing blocks. */ FOR_EACH_EDGE (e, ei, bb->preds) { @@ -944,7 +937,7 @@ /* This will free "pending". */ -static void +static void df_worklist_dataflow_doublequeue (struct dataflow *dataflow, bitmap pending, sbitmap considered, @@ -979,7 +972,7 @@ df_worklist_propagate_forward (dataflow, bb_index, bbindex_to_postorder, pending, considered); - else + else df_worklist_propagate_backward (dataflow, bb_index, bbindex_to_postorder, pending, considered); @@ -1000,13 +993,13 @@ } /* Worklist-based dataflow solver. It uses sbitmap as a worklist, - with "n"-th bit representing the n-th block in the reverse-postorder order. + with "n"-th bit representing the n-th block in the reverse-postorder order. The solver is a double-queue algorithm similar to the "double stack" solver from Cooper, Harvey and Kennedy, "Iterative data-flow analysis, Revisited". The only significant difference is that the worklist in this implementation is always sorted in RPO of the CFG visiting direction. */ -void +void df_worklist_dataflow (struct dataflow *dataflow, bitmap blocks_to_consider, int *blocks_in_postorder, @@ -1076,16 +1069,16 @@ } -/* Execute dataflow analysis on a single dataflow problem. +/* Execute dataflow analysis on a single dataflow problem. BLOCKS_TO_CONSIDER are the blocks whose solution can either be examined or will be computed. For calls from DF_ANALYZE, this is - the set of blocks that has been passed to DF_SET_BLOCKS. + the set of blocks that has been passed to DF_SET_BLOCKS. */ void -df_analyze_problem (struct dataflow *dflow, - bitmap blocks_to_consider, +df_analyze_problem (struct dataflow *dflow, + bitmap blocks_to_consider, int *postorder, int n_blocks) { timevar_push (dflow->problem->tv_id); @@ -1095,7 +1088,7 @@ dflow->problem->verify_start_fun (); #endif - /* (Re)Allocate the datastructures necessary to solve the problem. */ + /* (Re)Allocate the datastructures necessary to solve the problem. */ if (dflow->problem->alloc_fun) dflow->problem->alloc_fun (blocks_to_consider); @@ -1132,7 +1125,7 @@ bitmap current_all_blocks = BITMAP_ALLOC (&df_bitmap_obstack); bool everything; int i; - + if (df->postorder) free (df->postorder); if (df->postorder_inverted) @@ -1174,10 +1167,10 @@ { everything = false; bitmap_and_into (df->blocks_to_analyze, current_all_blocks); - df->n_blocks = df_prune_to_subcfg (df->postorder, + df->n_blocks = df_prune_to_subcfg (df->postorder, df->n_blocks, df->blocks_to_analyze); - df->n_blocks_inverted = df_prune_to_subcfg (df->postorder_inverted, - df->n_blocks_inverted, + df->n_blocks_inverted = df_prune_to_subcfg (df->postorder_inverted, + df->n_blocks_inverted, df->blocks_to_analyze); BITMAP_FREE (current_all_blocks); } @@ -1221,7 +1214,7 @@ /* Return the number of basic blocks from the last call to df_analyze. */ -int +int df_get_n_blocks (enum df_flow_dir dir) { gcc_assert (dir != DF_NONE); @@ -1237,7 +1230,7 @@ } -/* Return a pointer to the array of basic blocks in the reverse postorder. +/* Return a pointer to the array of basic blocks in the reverse postorder. Depending on the direction of the dataflow problem, it returns either the usual reverse postorder array or the reverse postorder of inverted traversal. */ @@ -1255,7 +1248,7 @@ return df->postorder; } -static struct df_problem user_problem; +static struct df_problem user_problem; static struct dataflow user_dflow; /* Interface for calling iterative dataflow with user defined @@ -1284,7 +1277,7 @@ df_worklist_dataflow (&user_dflow, blocks, postorder, n_blocks); } - + /*---------------------------------------------------------------------------- Functions to support limited incremental change. @@ -1307,7 +1300,7 @@ /* Set basic block info. */ static void -df_set_bb_info (struct dataflow *dflow, unsigned int index, +df_set_bb_info (struct dataflow *dflow, unsigned int index, void *bb_info) { gcc_assert (dflow->block_info); @@ -1317,12 +1310,12 @@ /* Mark the solutions as being out of date. */ -void +void df_mark_solutions_dirty (void) { if (df) { - int p; + int p; for (p = 1; p < df->num_problems_defined; p++) df->problems_in_order[p]->solutions_dirty = true; } @@ -1331,12 +1324,12 @@ /* Return true if BB needs it's transfer functions recomputed. */ -bool +bool df_get_bb_dirty (basic_block bb) { if (df && df_live) return bitmap_bit_p (df_live->out_of_date_transfer_functions, bb->index); - else + else return false; } @@ -1344,12 +1337,12 @@ /* Mark BB as needing it's transfer functions as being out of date. */ -void +void df_set_bb_dirty (basic_block bb) { if (df) { - int p; + int p; for (p = 1; p < df->num_problems_defined; p++) { struct dataflow *dflow = df->problems_in_order[p]; @@ -1366,7 +1359,7 @@ static void df_clear_bb_dirty (basic_block bb) { - int p; + int p; for (p = 1; p < df->num_problems_defined; p++) { struct dataflow *dflow = df->problems_in_order[p]; @@ -1377,7 +1370,7 @@ /* Called from the rtl_compact_blocks to reorganize the problems basic block info. */ -void +void df_compact_blocks (void) { int i, p; @@ -1403,7 +1396,7 @@ bitmap_set_bit (dflow->out_of_date_transfer_functions, EXIT_BLOCK); i = NUM_FIXED_BLOCKS; - FOR_EACH_BB (bb) + FOR_EACH_BB (bb) { if (bitmap_bit_p (tmp, bb->index)) bitmap_set_bit (dflow->out_of_date_transfer_functions, i); @@ -1421,20 +1414,20 @@ place in the block_info vector. Null out the copied item. The entry and exit blocks never move. */ i = NUM_FIXED_BLOCKS; - FOR_EACH_BB (bb) + FOR_EACH_BB (bb) { df_set_bb_info (dflow, i, problem_temps[bb->index]); problem_temps[bb->index] = NULL; i++; } - memset (dflow->block_info + i, 0, + memset (dflow->block_info + i, 0, (last_basic_block - i) *sizeof (void *)); /* Free any block infos that were not copied (and NULLed). These are from orphaned blocks. */ for (i = NUM_FIXED_BLOCKS; i < last_basic_block; i++) { - basic_block bb = BASIC_BLOCK (i); + basic_block bb = BASIC_BLOCK (i); if (problem_temps[i] && bb) dflow->problem->free_bb_fun (bb, problem_temps[i]); @@ -1453,7 +1446,7 @@ bitmap_copy (tmp, df->blocks_to_analyze); bitmap_clear (df->blocks_to_analyze); i = NUM_FIXED_BLOCKS; - FOR_EACH_BB (bb) + FOR_EACH_BB (bb) { if (bitmap_bit_p (tmp, bb->index)) bitmap_set_bit (df->blocks_to_analyze, i); @@ -1466,7 +1459,7 @@ free (problem_temps); i = NUM_FIXED_BLOCKS; - FOR_EACH_BB (bb) + FOR_EACH_BB (bb) { SET_BASIC_BLOCK (i, bb); bb->index = i; @@ -1488,7 +1481,7 @@ /* Shove NEW_BLOCK in at OLD_INDEX. Called from ifcvt to hack a block. There is no excuse for people to do this kind of thing. */ -void +void df_bb_replace (int old_index, basic_block new_block) { int new_block_index = new_block->index; @@ -1507,7 +1500,7 @@ { df_grow_bb_info (dflow); gcc_assert (df_get_bb_info (dflow, old_index) == NULL); - df_set_bb_info (dflow, old_index, + df_set_bb_info (dflow, old_index, df_get_bb_info (dflow, new_block_index)); } } @@ -1532,7 +1525,7 @@ if (!df) return; - + for (i = 0; i < df->num_problems_defined; i++) { struct dataflow *dflow = df->problems_in_order[i]; @@ -1541,7 +1534,7 @@ void *bb_info = df_get_bb_info (dflow, bb_index); if (bb_info) { - dflow->problem->free_bb_fun (bb, bb_info); + dflow->problem->free_bb_fun (bb, bb_info); df_set_bb_info (dflow, bb_index, NULL); } } @@ -1627,7 +1620,7 @@ if (df_lr->solutions_dirty) return; - if (saved_cfg == NULL) + if (saved_cfg == NULL) return; new_map = df_compute_cfg_image (); @@ -1655,7 +1648,7 @@ /* Return first def of REGNO within BB. */ -df_ref +df_ref df_bb_regno_first_def_find (basic_block bb, unsigned int regno) { rtx insn; @@ -1681,7 +1674,7 @@ /* Return last def of REGNO within BB. */ -df_ref +df_ref df_bb_regno_last_def_find (basic_block bb, unsigned int regno) { rtx insn; @@ -1708,7 +1701,7 @@ /* Finds the reference corresponding to the definition of REG in INSN. DF is the dataflow object. */ -df_ref +df_ref df_find_def (rtx insn, rtx reg) { unsigned int uid; @@ -1730,19 +1723,19 @@ } -/* Return true if REG is defined in INSN, zero otherwise. */ +/* Return true if REG is defined in INSN, zero otherwise. */ bool df_reg_defined (rtx insn, rtx reg) { return df_find_def (insn, reg) != NULL; } - + /* Finds the reference corresponding to the use of REG in INSN. DF is the dataflow object. */ - -df_ref + +df_ref df_find_use (rtx insn, rtx reg) { unsigned int uid; @@ -1758,26 +1751,26 @@ df_ref use = *use_rec; if (rtx_equal_p (DF_REF_REAL_REG (use), reg)) return use; - } + } if (df->changeable_flags & DF_EQ_NOTES) for (use_rec = DF_INSN_UID_EQ_USES (uid); *use_rec; use_rec++) { df_ref use = *use_rec; if (rtx_equal_p (DF_REF_REAL_REG (use), reg)) - return use; + return use; } return NULL; } -/* Return true if REG is referenced in INSN, zero otherwise. */ +/* Return true if REG is referenced in INSN, zero otherwise. */ bool df_reg_used (rtx insn, rtx reg) { return df_find_use (insn, reg) != NULL; } - + /*---------------------------------------------------------------------------- Debugging and printing functions. @@ -1902,18 +1895,18 @@ fprintf (file, "\n\nstarting region dump\n"); df_dump_start (file); - - EXECUTE_IF_SET_IN_BITMAP (df->blocks_to_analyze, 0, bb_index, bi) + + EXECUTE_IF_SET_IN_BITMAP (df->blocks_to_analyze, 0, bb_index, bi) { basic_block bb = BASIC_BLOCK (bb_index); - + df_print_bb_index (bb, file); df_dump_top (bb, file); df_dump_bottom (bb, file); } fprintf (file, "\n"); } - else + else df_dump (file); } @@ -1941,13 +1934,13 @@ { df_dump_problem_function fun = dflow->problem->dump_start_fun; if (fun) - fun(file); + fun(file); } } } -/* Dump the top of the block information for BB. */ +/* Dump the top of the block information for BB. */ void df_dump_top (basic_block bb, FILE *file) @@ -1964,13 +1957,13 @@ { df_dump_bb_problem_function bbfun = dflow->problem->dump_top_fun; if (bbfun) - bbfun (bb, file); + bbfun (bb, file); } } } -/* Dump the bottom of the block information for BB. */ +/* Dump the bottom of the block information for BB. */ void df_dump_bottom (basic_block bb, FILE *file) @@ -1987,7 +1980,7 @@ { df_dump_bb_problem_function bbfun = dflow->problem->dump_bottom_fun; if (bbfun) - bbfun (bb, file); + bbfun (bb, file); } } } @@ -2035,7 +2028,7 @@ { while (*mws) { - fprintf (file, "mw %c r[%d..%d]\n", + fprintf (file, "mw %c r[%d..%d]\n", (DF_MWS_REG_DEF_P (*mws)) ? 'd' : 'u', (*mws)->start_regno, (*mws)->end_regno); mws++; @@ -2043,8 +2036,8 @@ } -static void -df_insn_uid_debug (unsigned int uid, +static void +df_insn_uid_debug (unsigned int uid, bool follow_chain, FILE *file) { fprintf (file, "insn %d luid %d", @@ -2092,7 +2085,7 @@ INSN_UID (insn), BLOCK_FOR_INSN (insn)->index, DF_INSN_INFO_LUID (insn_info)); df_refs_chain_dump (DF_INSN_INFO_DEFS (insn_info), false, file); - + fprintf (file, " uses "); df_refs_chain_dump (DF_INSN_INFO_USES (insn_info), false, file); @@ -2127,7 +2120,13 @@ DF_REF_FLAGS (ref), DF_REF_TYPE (ref)); if (DF_REF_LOC (ref)) - fprintf (file, "loc %p(%p) chain ", (void *)DF_REF_LOC (ref), (void *)*DF_REF_LOC (ref)); + { + if (flag_dump_noaddr) + fprintf (file, "loc #(#) chain "); + else + fprintf (file, "loc %p(%p) chain ", (void *)DF_REF_LOC (ref), + (void *)*DF_REF_LOC (ref)); + } else fprintf (file, "chain "); df_chain_dump (DF_REF_CHAIN (ref), file);