From: Jeff Law Date: Thu, 28 Jun 2001 22:11:19 +0000 (-0600) Subject: Makefile.in (OBJS): Add df.o X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=10c4b247fd9f5a610f7a02dc21fa758173ed9aef;p=gcc.git Makefile.in (OBJS): Add df.o * Makefile.in (OBJS): Add df.o (df.o): Add dependencies. * basic-block.h (flow_depth_first_order_compute): Declare. * flow.c (flow_depth_first_order_compute): No longer declare. Make external. * df.c, df.h: New files. * po/POTFILES.in: Update for new files. From-SVN: r43647 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 6b7ac2938f1..fd30ddb31af 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,13 @@ +2001-06-28 Michael Hayes + Jeff Law + + * Makefile.in (OBJS): Add df.o + (df.o): Add dependencies. + * basic-block.h (flow_depth_first_order_compute): Declare. + * flow.c (flow_depth_first_order_compute): No longer declare. + Make external. + * df.c, df.h: New files. + 2001-06-28 Zack Weinberg * config/i386/i386.md: Global update to use new string syntax diff --git a/gcc/Makefile.in b/gcc/Makefile.in index 7534235083d..58ac2c18f03 100644 --- a/gcc/Makefile.in +++ b/gcc/Makefile.in @@ -735,18 +735,19 @@ C_OBJS = c-parse.o c-lang.o $(C_AND_OBJC_OBJS) OBJS = \ alias.o bb-reorder.o bitmap.o builtins.o caller-save.o calls.o \ combine.o conflict.o convert.o cse.o cselib.o dbxout.o ssa-dce.o \ - dependence.o diagnostic.o doloop.o dominance.o dwarf2asm.o dwarf2out.o \ - dwarfout.o emit-rtl.o except.o explow.o expmed.o expr.o final.o flow.o \ - fold-const.o function.o gcse.o genrtl.o ggc-common.o global.o graph.o \ - haifa-sched.o hash.o hashtable.o ifcvt.o insn-attrtab.o insn-emit.o \ - insn-extract.o insn-opinit.o insn-output.o insn-peep.o insn-recog.o \ - integrate.o intl.o jump.o lcm.o lists.o local-alloc.o loop.o mbchar.o \ - optabs.o params.o predict.o print-rtl.o print-tree.o profile.o real.o \ - recog.o reg-stack.o regclass.o regmove.o regrename.o reload.o \ - reload1.o reorg.o resource.o rtl.o rtlanal.o sbitmap.o sched-deps.o \ - sched-ebb.o sched-rgn.o sched-vis.o sdbout.o sibcall.o simplify-rtx.o \ - splay-tree.o ssa.o stmt.o stor-layout.o stringpool.o timevar.o \ - toplev.o tree.o unroll.o varasm.o varray.o version.o xcoffout.o \ + dependence.o df.o diagnostic.o doloop.o dominance.o dwarf2asm.o \ + dwarf2out.o dwarfout.o emit-rtl.o except.o explow.o expmed.o expr.o \ + final.o flow.o fold-const.o function.o gcse.o genrtl.o ggc-common.o \ + global.o graph.o haifa-sched.o hash.o hashtable.o ifcvt.o \ + insn-attrtab.o insn-emit.o insn-extract.o insn-opinit.o insn-output.o \ + insn-peep.o insn-recog.o integrate.o intl.o jump.o lcm.o lists.o \ + local-alloc.o loop.o mbchar.o optabs.o params.o predict.o print-rtl.o \ + print-tree.o profile.o real.o recog.o reg-stack.o regclass.o regmove.o \ + regrename.o reload.o reload1.o reorg.o resource.o rtl.o rtlanal.o \ + sbitmap.o sched-deps.o sched-ebb.o sched-rgn.o sched-vis.o sdbout.o \ + sibcall.o simplify-rtx.o splay-tree.o ssa.o stmt.o stor-layout.o \ + stringpool.o timevar.o toplev.o tree.o unroll.o varasm.o varray.o \ + version.o xcoffout.o \ $(GGC) $(out_object_file) $(EXTRA_OBJS) BACKEND = main.o libbackend.a @@ -1442,6 +1443,8 @@ ssa.o : ssa.c $(CONFIG_H) $(SYSTEM_H) $(REGS_H) varray.h $(EXPR_H) \ $(BASIC_BLOCK_H) output.h ssa.h ssa-dce.o : ssa-dce.c $(CONFIG_H) $(SYSTEM_H) $(RTL_H) hard-reg-set.h $(BASIC_BLOCK_H) \ ssa.h insn-config.h $(RECOG_H) output.h +df.o : df.c $(CONFIG_H) system.h $(RTL_H) insn-config.h $(RECOG_H) \ + function.h $(REGS_H) $(OBSTACK_H) hard-reg-set.h $(BASIC_BLOCK_H) df.h conflict.o : conflict.c $(CONFIG_H) $(SYSTEM_H) $(OBSTACK_H) $(HASHTAB_H) \ $(RTL_H) hard-reg-set.h $(BASIC_BLOCK_H) profile.o : profile.c $(CONFIG_H) $(SYSTEM_H) $(RTL_H) $(TREE_H) flags.h \ diff --git a/gcc/basic-block.h b/gcc/basic-block.h index 8e4aa4182ea..23e1e16511b 100644 --- a/gcc/basic-block.h +++ b/gcc/basic-block.h @@ -290,10 +290,12 @@ extern int flow_delete_block PARAMS ((basic_block)); extern void merge_blocks_nomove PARAMS ((basic_block, basic_block)); extern void tidy_fallthru_edge PARAMS ((edge, basic_block, basic_block)); +extern int flow_depth_first_order_compute PARAMS ((int *, int *)); extern void dump_edge_info PARAMS ((FILE *, edge, int)); extern void clear_edges PARAMS ((void)); extern void mark_critical_edges PARAMS ((void)); + /* Structure to hold information for each natural loop. */ struct loop { diff --git a/gcc/df.c b/gcc/df.c new file mode 100644 index 00000000000..4b049f55087 --- /dev/null +++ b/gcc/df.c @@ -0,0 +1,3746 @@ +/* Dataflow support routines. + Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc. + Contributed by Michael P. Hayes (m.hayes@elec.canterbury.ac.nz, + mhayes@redhat.com) + +This file is part of GNU CC. + +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. + +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. + +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. + + +OVERVIEW: + +This file provides some dataflow routines for computing reaching defs, +upward exposed uses, live variables, def-use chains, and use-def +chains. The global dataflow is performed using simple iterative +methods with a worklist and could be sped up by ordering the blocks +with a depth first search order. + +A `struct ref' data structure (ref) is allocated for every register +reference (def or use) and this records the insn and bb the ref is +found within. The refs are linked together in chains of uses and defs +for each insn and for each register. Each ref also has a chain field +that links all the use refs for a def or all the def refs for a use. +This is used to create use-def or def-use chains. + + +USAGE: + +Here's an example of using the dataflow routines. + + struct df *df; + + df = df_init (); + + df_analyse (df, 0, DF_ALL); + + df_dump (df, DF_ALL, stderr); + + df_finish (df); + + +df_init simply creates a poor man's object (df) that needs to be +passed to all the dataflow routines. df_finish destroys this +object and frees up any allocated memory. + +df_analyse performs the following: + +1. Records defs and uses by scanning the insns in each basic block + or by scanning the insns queued by df_insn_modify. +2. Links defs and uses into insn-def and insn-use chains. +3. Links defs and uses into reg-def and reg-use chains. +4. Assigns LUIDs to each insn (for modified blocks). +5. Calculates local reaching definitions. +6. Calculates global reaching definitions. +7. Creates use-def chains. +8. Calculates local reaching uses (upwards exposed uses). +9. Calculates global reaching uses. +10. Creates def-use chains. +11. Calculates local live registers. +12. Calculates global live registers. +13. Calculates register lifetimes and determines local registers. + + +PHILOSOPHY: + +Note that the dataflow information is not updated for every newly +deleted or created insn. If the dataflow information requires +updating then all the changed, new, or deleted insns needs to be +marked with df_insn_modify (or df_insns_modify) either directly or +indirectly (say through calling df_insn_delete). df_insn_modify +marks all the modified insns to get processed the next time df_analyse + is called. + +Beware that tinkering with insns may invalidate the dataflow information. +The philosophy behind these routines is that once the dataflow +information has been gathered, the user should store what they require +before they tinker with any insn. Once a reg is replaced, for example, +then the reg-def/reg-use chains will point to the wrong place. Once a +whole lot of changes have been made, df_analyse can be called again +to update the dataflow information. Currently, this is not very smart +with regard to propagating changes to the dataflow so it should not +be called very often. + + +DATA STRUCTURES: + +The basic object is a 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, + insn-def, insn-use, def-use, and use-def lists. For example, +the reg-def lists contain all the refs that define a given register +while the insn-use lists contain all the refs used by an insn. + +Note that the reg-def and reg-use chains are generally short (except for the +hard registers) and thus it is much faster to search these chains +rather than searching the def or use bitmaps. + +If the insns are in SSA form then the reg-def and use-def lists +should only contain the single defining ref. + +TODO: + +1) Incremental dataflow analysis. + +Note that if a loop invariant insn is hoisted (or sunk), we do not +need to change the def-use or use-def chains. All we have to do is to +change the bb field for all the associated defs and uses and to +renumber the LUIDs for the original and new basic blocks of the insn. + +When shadowing loop mems we create new uses and defs for new pseudos +so we do not affect the existing dataflow information. + +My current strategy is to queue up all modified, created, or deleted +insns so when df_analyse is called we can easily determine all the new +or deleted refs. Currently the global dataflow information is +recomputed from scratch but this could be propagated more efficiently. + +2) Improved global data flow computation using depth first search. + +3) Reduced memory requirements. + +We could operate a pool of ref structures. When a ref is deleted it +gets returned to the pool (say by linking on to a chain of free refs). +This will require a pair of bitmaps for defs and uses so that we can +tell which ones have been changed. Alternatively, we could +periodically squeeze the def and use tables and associated bitmaps and +renumber the def and use ids. + +4) Ordering of reg-def and reg-use lists. + +Should the first entry in the def list be the first def (within a BB)? +Similarly, should the first entry in the use list be the last use +(within a BB)? + +5) Working with a sub-CFG. + +Often the whole CFG does not need to be analysed, for example, +when optimising a loop, only certain registers are of interest. +Perhaps there should be a bitmap argument to df_analyse to specify + which registers should be analysed? */ + +#define HANDLE_SUBREG + +#include "config.h" +#include "system.h" +#include "rtl.h" +#include "insn-config.h" +#include "recog.h" +#include "function.h" +#include "regs.h" +#include "obstack.h" +#include "hard-reg-set.h" +#include "basic-block.h" +#include "bitmap.h" +#include "df.h" + + +#define FOR_ALL_BBS(BB, CODE) \ +do { \ + int node_; \ + for (node_ = 0; node_ < n_basic_blocks; node_++) \ + {(BB) = BASIC_BLOCK (node_); CODE;};} while (0) + +#define FOR_EACH_BB_IN_BITMAP(BITMAP, MIN, BB, CODE) \ +do { \ + unsigned int node_; \ + EXECUTE_IF_SET_IN_BITMAP (BITMAP, MIN, node_, \ + {(BB) = BASIC_BLOCK (node_); CODE;});} while (0) + +#define FOR_EACH_BB_IN_BITMAP_REV(BITMAP, MIN, BB, CODE) \ +do { \ + unsigned int node_; \ + EXECUTE_IF_SET_IN_BITMAP_REV (BITMAP, node_, \ + {(BB) = BASIC_BLOCK (node_); CODE;});} while (0) + +#define FOR_EACH_BB_IN_SBITMAP(BITMAP, MIN, BB, CODE) \ +do { \ + unsigned int node_; \ + EXECUTE_IF_SET_IN_SBITMAP (BITMAP, MIN, node_, \ + {(BB) = BASIC_BLOCK (node_); CODE;});} while (0) + +#define obstack_chunk_alloc xmalloc +#define obstack_chunk_free free + +static struct obstack df_ref_obstack; +static struct df *ddf; + +static void df_reg_table_realloc PARAMS((struct df *, int)); +#if 0 +static void df_def_table_realloc PARAMS((struct df *, int)); +#endif +static void df_insn_table_realloc PARAMS((struct df *, int)); +static void df_bitmaps_alloc PARAMS((struct df *, int)); +static void df_bitmaps_free PARAMS((struct df *, int)); +static void df_free PARAMS((struct df *)); +static void df_alloc PARAMS((struct df *, int)); + +static rtx df_reg_clobber_gen PARAMS((unsigned int)); +static rtx df_reg_use_gen PARAMS((unsigned int)); + +static inline struct df_link *df_link_create PARAMS((struct ref *, + struct df_link *)); +static struct df_link *df_ref_unlink PARAMS((struct df_link **, struct ref *)); +static void df_def_unlink PARAMS((struct df *, struct ref *)); +static void df_use_unlink PARAMS((struct df *, struct ref *)); +static void df_insn_refs_unlink PARAMS ((struct df *, basic_block, rtx)); +static void df_bb_refs_unlink PARAMS ((struct df *, basic_block)); +#if 0 +static void df_refs_unlink PARAMS ((struct df *, bitmap)); +#endif + +static struct ref *df_ref_create PARAMS((struct df *, + rtx, rtx *, basic_block, rtx, + enum df_ref_type)); +static void df_ref_record_1 PARAMS((struct df *, rtx, rtx *, + basic_block, rtx, enum df_ref_type)); +static void df_ref_record PARAMS((struct df *, rtx, rtx *, + basic_block bb, rtx, enum df_ref_type)); +static void df_def_record_1 PARAMS((struct df *, rtx, basic_block, rtx)); +static void df_defs_record PARAMS((struct df *, rtx, basic_block, rtx)); +static void df_uses_record PARAMS((struct df *, rtx *, + enum df_ref_type, basic_block, rtx)); +static void df_insn_refs_record PARAMS((struct df *, basic_block, rtx)); +static void df_bb_refs_record PARAMS((struct df *, basic_block)); +static void df_refs_record PARAMS((struct df *, bitmap)); + +static int df_visit_next PARAMS ((struct df *, sbitmap)); +static void df_bb_reg_def_chain_create PARAMS((struct df *, basic_block)); +static void df_reg_def_chain_create PARAMS((struct df *, bitmap)); +static void df_bb_reg_use_chain_create PARAMS((struct df *, basic_block)); +static void df_reg_use_chain_create PARAMS((struct df *, bitmap)); +static void df_bb_du_chain_create PARAMS((struct df *, basic_block, bitmap)); +static void df_du_chain_create PARAMS((struct df *, bitmap)); +static void df_bb_ud_chain_create PARAMS((struct df *, basic_block)); +static void df_ud_chain_create PARAMS((struct df *, bitmap)); +static void df_rd_global_compute PARAMS((struct df *, bitmap)); +static void df_ru_global_compute PARAMS((struct df *, bitmap)); +static void df_lr_global_compute PARAMS((struct df *, bitmap)); +static void df_bb_rd_local_compute PARAMS((struct df *, basic_block)); +static void df_rd_local_compute PARAMS((struct df *, bitmap)); +static void df_bb_ru_local_compute PARAMS((struct df *, basic_block)); +static void df_ru_local_compute PARAMS((struct df *, bitmap)); +static void df_bb_lr_local_compute PARAMS((struct df *, basic_block)); +static void df_lr_local_compute PARAMS((struct df *, bitmap)); +static void df_bb_reg_info_compute PARAMS((struct df *, basic_block, bitmap)); +static void df_reg_info_compute PARAMS((struct df *, bitmap)); + +static int df_bb_luids_set PARAMS((struct df *df, basic_block)); +static int df_luids_set PARAMS((struct df *df, bitmap)); + +static int df_modified_p PARAMS ((struct df *, bitmap)); +static int df_refs_queue PARAMS ((struct df *)); +static int df_refs_process PARAMS ((struct df *)); +static int df_bb_refs_update PARAMS ((struct df *, basic_block)); +static int df_refs_update PARAMS ((struct df *)); +static void df_analyse_1 PARAMS((struct df *, bitmap, int, int)); + +static void df_insns_modify PARAMS((struct df *, basic_block, + rtx, rtx)); +static int df_rtx_mem_replace PARAMS ((rtx *, void *)); +static int df_rtx_reg_replace PARAMS ((rtx *, void *)); +void df_refs_reg_replace PARAMS ((struct df *, bitmap, + struct df_link *, rtx, rtx)); + +static int df_def_dominates_all_uses_p PARAMS((struct df *, struct ref *def)); +static int df_def_dominates_uses_p PARAMS((struct df *, + struct ref *def, bitmap)); +static struct ref *df_bb_regno_last_use_find PARAMS((struct df *, basic_block, + unsigned int)); +static struct ref *df_bb_regno_first_def_find PARAMS((struct df *, basic_block, + unsigned int)); +static struct ref *df_bb_insn_regno_last_use_find PARAMS((struct df *, + basic_block, + rtx, unsigned int)); +static struct ref *df_bb_insn_regno_first_def_find PARAMS((struct df *, + basic_block, + rtx, unsigned int)); + +static void df_chain_dump PARAMS((struct df_link *, FILE *file)); +static void df_chain_dump_regno PARAMS((struct df_link *, FILE *file)); +static void df_regno_debug PARAMS ((struct df *, unsigned int, FILE *)); +static void df_ref_debug PARAMS ((struct df *, struct ref *, FILE *)); + + +/* Local memory allocation/deallocation routines. */ + + +/* Increase the insn info table by SIZE more elements. */ +static void +df_insn_table_realloc (df, size) + struct df *df; + int size; +{ + /* Make table 25 percent larger by default. */ + if (! size) + size = df->insn_size / 4; + + size += df->insn_size; + + df->insns = (struct insn_info *) + xrealloc (df->insns, size * sizeof (struct insn_info)); + + memset (df->insns + df->insn_size, 0, + (size - df->insn_size) * sizeof (struct insn_info)); + + df->insn_size = size; + + if (! df->insns_modified) + { + df->insns_modified = BITMAP_XMALLOC (); + bitmap_zero (df->insns_modified); + } +} + + +/* Increase the reg info table by SIZE more elements. */ +static void +df_reg_table_realloc (df, size) + struct df *df; + int size; +{ + /* Make table 25 percent larger by default. */ + if (! size) + size = df->reg_size / 4; + + size += df->reg_size; + + df->regs = (struct reg_info *) + xrealloc (df->regs, size * sizeof (struct reg_info)); + + /* Zero the new entries. */ + memset (df->regs + df->reg_size, 0, + (size - df->reg_size) * sizeof (struct reg_info)); + + df->reg_size = size; +} + + +#if 0 +/* Not currently used. */ +static void +df_def_table_realloc (df, size) + struct df *df; + int size; +{ + int i; + struct ref *refs; + + /* Make table 25 percent larger by default. */ + if (! size) + size = df->def_size / 4; + + df->def_size += size; + df->defs = xrealloc (df->defs, + df->def_size * sizeof (*df->defs)); + + /* Allocate a new block of memory and link into list of blocks + that will need to be freed later. */ + + refs = xmalloc (size * sizeof (*refs)); + + /* Link all the new refs together, overloading the chain field. */ + for (i = 0; i < size - 1; i++) + refs[i].chain = (struct df_link *)(refs + i + 1); + refs[size - 1].chain = 0; +} +#endif + + + +/* Allocate bitmaps for each basic block. */ +static void +df_bitmaps_alloc (df, flags) + struct df *df; + int flags; +{ + unsigned int i; + int dflags = 0; + + /* Free the bitmaps if they need resizing. */ + if ((flags & DF_LR) && df->n_regs < (unsigned int)max_reg_num ()) + dflags |= DF_LR | DF_RU; + if ((flags & DF_RU) && df->n_uses < df->use_id) + dflags |= DF_RU; + if ((flags & DF_RD) && df->n_defs < df->def_id) + dflags |= DF_RD; + + if (dflags) + df_bitmaps_free (df, dflags); + + df->n_defs = df->def_id; + df->n_uses = df->use_id; + + for (i = 0; i < df->n_bbs; i++) + { + basic_block bb = BASIC_BLOCK (i); + struct bb_info *bb_info = DF_BB_INFO (df, bb); + + if (flags & DF_RD && ! bb_info->rd_in) + { + /* Allocate bitmaps for reaching definitions. */ + bb_info->rd_kill = BITMAP_XMALLOC (); + bitmap_zero (bb_info->rd_kill); + bb_info->rd_gen = BITMAP_XMALLOC (); + bitmap_zero (bb_info->rd_gen); + bb_info->rd_in = BITMAP_XMALLOC (); + bb_info->rd_out = BITMAP_XMALLOC (); + bb_info->rd_valid = 0; + } + + if (flags & DF_RU && ! bb_info->ru_in) + { + /* Allocate bitmaps for upward exposed uses. */ + bb_info->ru_kill = BITMAP_XMALLOC (); + bitmap_zero (bb_info->ru_kill); + /* Note the lack of symmetry. */ + bb_info->ru_gen = BITMAP_XMALLOC (); + bitmap_zero (bb_info->ru_gen); + bb_info->ru_in = BITMAP_XMALLOC (); + bb_info->ru_out = BITMAP_XMALLOC (); + bb_info->ru_valid = 0; + } + + if (flags & DF_LR && ! bb_info->lr_in) + { + /* Allocate bitmaps for live variables. */ + bb_info->lr_def = BITMAP_XMALLOC (); + bitmap_zero (bb_info->lr_def); + bb_info->lr_use = BITMAP_XMALLOC (); + bitmap_zero (bb_info->lr_use); + bb_info->lr_in = BITMAP_XMALLOC (); + bb_info->lr_out = BITMAP_XMALLOC (); + bb_info->lr_valid = 0; + } + } +} + + +/* Free bitmaps for each basic block. */ +static void +df_bitmaps_free (df, flags) + struct df *df ATTRIBUTE_UNUSED; + int flags; +{ + unsigned int i; + + for (i = 0; i < df->n_bbs; i++) + { + basic_block bb = BASIC_BLOCK (i); + struct bb_info *bb_info = DF_BB_INFO (df, bb); + + if (!bb_info) + continue; + + if ((flags & DF_RD) && bb_info->rd_in) + { + /* Free bitmaps for reaching definitions. */ + BITMAP_XFREE (bb_info->rd_kill); + bb_info->rd_kill = NULL; + BITMAP_XFREE (bb_info->rd_gen); + bb_info->rd_gen = NULL; + BITMAP_XFREE (bb_info->rd_in); + bb_info->rd_in = NULL; + BITMAP_XFREE (bb_info->rd_out); + bb_info->rd_out = NULL; + } + + if ((flags & DF_RU) && bb_info->ru_in) + { + /* Free bitmaps for upward exposed uses. */ + BITMAP_XFREE (bb_info->ru_kill); + bb_info->ru_kill = NULL; + BITMAP_XFREE (bb_info->ru_gen); + bb_info->ru_gen = NULL; + BITMAP_XFREE (bb_info->ru_in); + bb_info->ru_in = NULL; + BITMAP_XFREE (bb_info->ru_out); + bb_info->ru_out = NULL; + } + + if ((flags & DF_LR) && bb_info->lr_in) + { + /* Free bitmaps for live variables. */ + BITMAP_XFREE (bb_info->lr_def); + bb_info->lr_def = NULL; + BITMAP_XFREE (bb_info->lr_use); + bb_info->lr_use = NULL; + BITMAP_XFREE (bb_info->lr_in); + bb_info->lr_in = NULL; + BITMAP_XFREE (bb_info->lr_out); + bb_info->lr_out = NULL; + } + } + df->flags &= ~(flags & (DF_RD | DF_RU | DF_LR)); +} + + +/* Allocate and initialise dataflow memory. */ +static void +df_alloc (df, n_regs) + struct df *df; + int n_regs; +{ + int n_insns; + int i; + + gcc_obstack_init (&df_ref_obstack); + + /* Perhaps we should use LUIDs to save memory for the insn_refs + table. This is only a small saving; a few pointers. */ + n_insns = get_max_uid () + 1; + + df->def_id = 0; + df->n_defs = 0; + /* Approximate number of defs by number of insns. */ + df->def_size = n_insns; + df->defs = xmalloc (df->def_size * sizeof (*df->defs)); + + df->use_id = 0; + df->n_uses = 0; + /* Approximate number of uses by twice number of insns. */ + df->use_size = n_insns * 2; + df->uses = xmalloc (df->use_size * sizeof (*df->uses)); + + df->n_regs = n_regs; + df->n_bbs = n_basic_blocks; + + /* Allocate temporary working array used during local dataflow analysis. */ + df->reg_def_last = xmalloc (df->n_regs * sizeof (struct ref *)); + + df_insn_table_realloc (df, n_insns); + + df_reg_table_realloc (df, df->n_regs); + + df->bbs_modified = BITMAP_XMALLOC (); + bitmap_zero (df->bbs_modified); + + df->flags = 0; + + df->bbs = xcalloc (df->n_bbs, sizeof (struct bb_info)); + + df->all_blocks = BITMAP_XMALLOC (); + for (i = 0; i < n_basic_blocks; i++) + bitmap_set_bit (df->all_blocks, i); +} + + +/* Free all the dataflow info. */ +static void +df_free (df) + struct df *df; +{ + df_bitmaps_free (df, DF_ALL); + + if (df->bbs) + free (df->bbs); + df->bbs = 0; + + if (df->insns) + free (df->insns); + df->insns = 0; + df->insn_size = 0; + + if (df->defs) + free (df->defs); + df->defs = 0; + df->def_size = 0; + df->def_id = 0; + + if (df->uses) + free (df->uses); + df->uses = 0; + df->use_size = 0; + df->use_id = 0; + + if (df->regs) + free (df->regs); + df->regs = 0; + df->reg_size = 0; + + if (df->bbs_modified) + BITMAP_XFREE (df->bbs_modified); + df->bbs_modified = 0; + + if (df->insns_modified) + BITMAP_XFREE (df->insns_modified); + df->insns_modified = 0; + + BITMAP_XFREE (df->all_blocks); + df->all_blocks = 0; + + obstack_free (&df_ref_obstack, NULL); +} + +/* Local miscellaneous routines. */ + +/* Return a USE for register REGNO. */ +static rtx df_reg_use_gen (regno) + unsigned int regno; +{ + rtx reg; + rtx use; + + reg = regno >= FIRST_PSEUDO_REGISTER + ? regno_reg_rtx[regno] : gen_rtx_REG (reg_raw_mode[regno], regno); + + use = gen_rtx_USE (GET_MODE (reg), reg); + return use; +} + + +/* Return a CLOBBER for register REGNO. */ +static rtx df_reg_clobber_gen (regno) + unsigned int regno; +{ + rtx reg; + rtx use; + + reg = regno >= FIRST_PSEUDO_REGISTER + ? regno_reg_rtx[regno] : gen_rtx_REG (reg_raw_mode[regno], regno); + + use = gen_rtx_CLOBBER (GET_MODE (reg), reg); + return use; +} + +/* Local chain manipulation routines. */ + +/* Create a link in a def-use or use-def chain. */ +static inline struct df_link * +df_link_create (ref, next) + struct ref *ref; + struct df_link *next; +{ + struct df_link *link; + + link = (struct df_link *) obstack_alloc (&df_ref_obstack, + sizeof (*link)); + link->next = next; + link->ref = ref; + return link; +} + + +/* Add REF to chain head pointed to by PHEAD. */ +static struct df_link * +df_ref_unlink (phead, ref) + struct df_link **phead; + struct ref *ref; +{ + struct df_link *link = *phead; + + if (link) + { + if (! link->next) + { + /* Only a single ref. It must be the one we want. + If not, the def-use and use-def chains are likely to + be inconsistent. */ + if (link->ref != ref) + abort (); + /* Now have an empty chain. */ + *phead = NULL; + } + else + { + /* Multiple refs. One of them must be us. */ + if (link->ref == ref) + *phead = link->next; + else + { + /* Follow chain. */ + for (; link->next; link = link->next) + { + if (link->next->ref == ref) + { + /* Unlink from list. */ + link->next = link->next->next; + return link->next; + } + } + } + } + } + return link; +} + + +/* Unlink REF from all def-use/use-def chains, etc. */ +int +df_ref_remove (df, ref) + struct df *df; + struct ref *ref; +{ + if (DF_REF_REG_DEF_P (ref)) + { + df_def_unlink (df, ref); + df_ref_unlink (&df->insns[DF_REF_INSN_UID (ref)].defs, ref); + } + else + { + df_use_unlink (df, ref); + df_ref_unlink (&df->insns[DF_REF_INSN_UID (ref)].uses, ref); + } + return 1; +} + + +/* Unlink DEF from use-def and reg-def chains. */ +static void +df_def_unlink (df, def) + struct df *df ATTRIBUTE_UNUSED; + struct ref *def; +{ + struct df_link *du_link; + unsigned int dregno = DF_REF_REGNO (def); + + /* Follow def-use chain to find all the uses of this def. */ + for (du_link = DF_REF_CHAIN (def); du_link; du_link = du_link->next) + { + struct ref *use = du_link->ref; + + /* Unlink this def from the use-def chain. */ + df_ref_unlink (&DF_REF_CHAIN (use), def); + } + DF_REF_CHAIN (def) = 0; + + /* Unlink def from reg-def chain. */ + df_ref_unlink (&df->regs[dregno].defs, def); + + df->defs[DF_REF_ID (def)] = 0; +} + + +/* Unlink use from def-use and reg-use chains. */ +static void +df_use_unlink (df, use) + struct df *df ATTRIBUTE_UNUSED; + struct ref *use; +{ + struct df_link *ud_link; + unsigned int uregno = DF_REF_REGNO (use); + + /* Follow use-def chain to find all the defs of this use. */ + for (ud_link = DF_REF_CHAIN (use); ud_link; ud_link = ud_link->next) + { + struct ref *def = ud_link->ref; + + /* Unlink this use from the def-use chain. */ + df_ref_unlink (&DF_REF_CHAIN (def), use); + } + DF_REF_CHAIN (use) = 0; + + /* Unlink use from reg-use chain. */ + df_ref_unlink (&df->regs[uregno].uses, use); + + df->uses[DF_REF_ID (use)] = 0; +} + +/* Local routines for recording refs. */ + + +/* Create a new ref of type DF_REF_TYPE for register REG at address + LOC within INSN of BB. */ +static struct ref * +df_ref_create (df, reg, loc, bb, insn, ref_type) + struct df *df; + rtx reg; + rtx *loc; + basic_block bb; + rtx insn; + enum df_ref_type ref_type; +{ + struct ref *this_ref; + unsigned int uid; + + this_ref = (struct ref *) obstack_alloc (&df_ref_obstack, + sizeof (*this_ref)); + DF_REF_REG (this_ref) = reg; + DF_REF_LOC (this_ref) = loc; + DF_REF_BB (this_ref) = bb; + DF_REF_INSN (this_ref) = insn; + DF_REF_CHAIN (this_ref) = 0; + DF_REF_TYPE (this_ref) = ref_type; + uid = INSN_UID (insn); + + if (ref_type == DF_REF_REG_DEF) + { + if (df->def_id >= df->def_size) + { + /* Make table 25 percent larger. */ + df->def_size += (df->def_size / 4); + df->defs = xrealloc (df->defs, + df->def_size * sizeof (*df->defs)); + } + DF_REF_ID (this_ref) = df->def_id; + df->defs[df->def_id++] = this_ref; + } + else + { + if (df->use_id >= df->use_size) + { + /* Make table 25 percent larger. */ + df->use_size += (df->use_size / 4); + df->uses = xrealloc (df->uses, + df->use_size * sizeof (*df->uses)); + } + DF_REF_ID (this_ref) = df->use_id; + df->uses[df->use_id++] = this_ref; + } + return this_ref; +} + + +/* Create a new reference of type DF_REF_TYPE for a single register REG, + used inside the LOC rtx of INSN. */ +static void +df_ref_record_1 (df, reg, loc, bb, insn, ref_type) + struct df *df; + rtx reg; + rtx *loc; + basic_block bb; + rtx insn; + enum df_ref_type ref_type; +{ + df_ref_create (df, reg, loc, bb, insn, ref_type); +} + + +/* Create new references of type DF_REF_TYPE for each part of register REG + at address LOC within INSN of BB. */ +static void +df_ref_record (df, reg, loc, bb, insn, ref_type) + struct df *df; + rtx reg; + rtx *loc; + basic_block bb; + rtx insn; + enum df_ref_type ref_type; +{ + unsigned int regno; + + if (GET_CODE (reg) != REG && GET_CODE (reg) != SUBREG) + abort (); + + /* For the reg allocator we are interested in some SUBREG rtx's, but not + all. Notably only those representing a word extraction from a multi-word + reg. As written in the docu those should have the form + (subreg:SI (reg:M A) N), with size(SImode) > size(Mmode). + XXX Is that true? We could also use the global word_mode variable. */ + if (GET_CODE (reg) == SUBREG + && (GET_MODE_SIZE (GET_MODE (reg)) < GET_MODE_SIZE (word_mode) + || GET_MODE_SIZE (GET_MODE (reg)) + >= GET_MODE_SIZE (GET_MODE (SUBREG_REG (reg))))) + { + loc = &SUBREG_REG (reg); + reg = *loc; + } + + regno = REGNO (GET_CODE (reg) == SUBREG ? SUBREG_REG (reg) : reg); + if (regno < FIRST_PSEUDO_REGISTER) + { + int i; + int endregno; + + if (! (df->flags & DF_HARD_REGS)) + return; + + /* GET_MODE (reg) is correct here. We don't want to go into a SUBREG + for the mode, because we only want to add references to regs, which + are really referenced. E.g. a (subreg:SI (reg:DI 0) 0) does _not_ + reference the whole reg 0 in DI mode (which would also include + reg 1, at least, if 0 and 1 are SImode registers). */ + endregno = regno + HARD_REGNO_NREGS (regno, GET_MODE (reg)); + + for (i = regno; i < endregno; i++) + df_ref_record_1 (df, gen_rtx_REG (reg_raw_mode[i], i), + loc, bb, insn, ref_type); + } + else + { + df_ref_record_1 (df, reg, loc, bb, insn, ref_type); + } +} + + +/* Process all the registers defined in the rtx, X. */ +static void +df_def_record_1 (df, x, bb, insn) + struct df *df; + rtx x; + basic_block bb; + rtx insn; +{ + rtx *loc = &SET_DEST (x); + rtx dst = *loc; + + /* Some targets place small structures in registers for + return values of functions. */ + if (GET_CODE (dst) == PARALLEL && GET_MODE (dst) == BLKmode) + { + int i; + + for (i = XVECLEN (dst, 0) - 1; i >= 0; i--) + df_def_record_1 (df, XVECEXP (dst, 0, i), bb, insn); + return; + } + + /* May be, we should flag the use of strict_low_part somehow. Might be + handy for the reg allocator. */ +#ifdef HANDLE_SUBREG + while (GET_CODE (dst) == STRICT_LOW_PART + || GET_CODE (dst) == ZERO_EXTRACT + || GET_CODE (dst) == SIGN_EXTRACT) + { + loc = &XEXP (dst, 0); + dst = *loc; + } + /* For the reg allocator we are interested in exact register references. + This means, we want to know, if only a part of a register is + used/defd. */ +/* + if (GET_CODE (dst) == SUBREG) + { + loc = &XEXP (dst, 0); + dst = *loc; + } */ +#else + + while (GET_CODE (dst) == SUBREG + || GET_CODE (dst) == ZERO_EXTRACT + || GET_CODE (dst) == SIGN_EXTRACT + || GET_CODE (dst) == STRICT_LOW_PART) + { + loc = &XEXP (dst, 0); + dst = *loc; + } +#endif + + if (GET_CODE (dst) == REG + || (GET_CODE (dst) == SUBREG && GET_CODE (SUBREG_REG (dst)) == REG)) + df_ref_record (df, dst, loc, bb, insn, DF_REF_REG_DEF); +} + + +/* Process all the registers defined in the pattern rtx, X. */ +static void +df_defs_record (df, x, bb, insn) + struct df *df; + rtx x; + basic_block bb; + rtx insn; +{ + RTX_CODE code = GET_CODE (x); + + if (code == SET || code == CLOBBER) + { + /* Mark the single def within the pattern. */ + df_def_record_1 (df, x, bb, insn); + } + else if (code == PARALLEL) + { + int i; + + /* Mark the multiple defs within the pattern. */ + for (i = XVECLEN (x, 0) - 1; i >= 0; i--) + { + code = GET_CODE (XVECEXP (x, 0, i)); + if (code == SET || code == CLOBBER) + df_def_record_1 (df, XVECEXP (x, 0, i), bb, insn); + } + } +} + + +/* Process all the registers used in the rtx at address LOC. */ +static void +df_uses_record (df, loc, ref_type, bb, insn) + struct df *df; + rtx *loc; + enum df_ref_type ref_type; + basic_block bb; + rtx insn; +{ + RTX_CODE code; + rtx x; + + retry: + x = *loc; + code = GET_CODE (x); + switch (code) + { + case LABEL_REF: + case SYMBOL_REF: + case CONST_INT: + case CONST: + case CONST_DOUBLE: + case PC: + case ADDR_VEC: + case ADDR_DIFF_VEC: + return; + + case CLOBBER: + /* If we are clobbering a MEM, mark any registers inside the address + as being used. */ + if (GET_CODE (XEXP (x, 0)) == MEM) + df_uses_record (df, &XEXP (XEXP (x, 0), 0), + DF_REF_REG_MEM_STORE, bb, insn); + + /* If we're clobbering a REG then we have a def so ignore. */ + return; + + case MEM: + df_uses_record (df, &XEXP (x, 0), DF_REF_REG_MEM_LOAD, bb, insn); + return; + + case SUBREG: + /* While we're here, optimize this case. */ +#if defined(HANDLE_SUBREG) + + /* In case the SUBREG is not of a register, don't optimize. */ + if (GET_CODE (SUBREG_REG (x)) != REG) + { + loc = &SUBREG_REG (x); + df_uses_record (df, loc, ref_type, bb, insn); + return; + } +#else + loc = &SUBREG_REG (x); + x = *loc; + if (GET_CODE (x) != REG) + { + df_uses_record (df, loc, ref_type, bb, insn); + return; + } +#endif + + /* ... Fall through ... */ + + case REG: + /* See a register (or subreg) other than being set. */ + df_ref_record (df, x, loc, bb, insn, ref_type); + return; + + case SET: + { + rtx dst = SET_DEST (x); + int use_dst = 0; + + /* If storing into MEM, don't show it as being used. But do + show the address as being used. */ + if (GET_CODE (dst) == MEM) + { + df_uses_record (df, &XEXP (dst, 0), + DF_REF_REG_MEM_STORE, + bb, insn); + df_uses_record (df, &SET_SRC (x), DF_REF_REG_USE, bb, insn); + return; + } + +#if 1 && defined(HANDLE_SUBREG) + /* Look for sets that perform a read-modify-write. */ + while (GET_CODE (dst) == STRICT_LOW_PART + || GET_CODE (dst) == ZERO_EXTRACT + || GET_CODE (dst) == SIGN_EXTRACT) + { + if (GET_CODE (dst) == STRICT_LOW_PART) + { + dst = XEXP (dst, 0); + if (GET_CODE (dst) != SUBREG) + abort (); + /* A strict_low_part uses the whole reg not only the subreg. */ + df_uses_record (df, &SUBREG_REG (dst), DF_REF_REG_USE, bb, insn); + } + else + { + df_uses_record (df, &XEXP (dst, 0), DF_REF_REG_USE, bb, insn); + dst = XEXP (dst, 0); + } + } + if (GET_CODE (dst) == SUBREG) + { + /* Paradoxical or too small subreg's are read-mod-write. */ + if (GET_MODE_SIZE (GET_MODE (dst)) < GET_MODE_SIZE (word_mode) + || GET_MODE_SIZE (GET_MODE (dst)) + >= GET_MODE_SIZE (GET_MODE (SUBREG_REG (dst)))) + use_dst = 1; + } + /* In the original code also some SUBREG rtx's were considered + read-modify-write (those with + REG_SIZE(SUBREG_REG(dst)) > REG_SIZE(dst) ) + e.g. a (subreg:QI (reg:SI A) 0). I can't see this. The only + reason for a read cycle for reg A would be to somehow preserve + the bits outside of the subreg:QI. But for this a strict_low_part + was necessary anyway, and this we handled already. */ +#else + while (GET_CODE (dst) == STRICT_LOW_PART + || GET_CODE (dst) == ZERO_EXTRACT + || GET_CODE (dst) == SIGN_EXTRACT + || GET_CODE (dst) == SUBREG) + { + /* A SUBREG of a smaller size does not use the old value. */ + if (GET_CODE (dst) != SUBREG + || (REG_SIZE (SUBREG_REG (dst)) > REG_SIZE (dst))) + use_dst = 1; + dst = XEXP (dst, 0); + } +#endif + + if ((GET_CODE (dst) == PARALLEL && GET_MODE (dst) == BLKmode) + || GET_CODE (dst) == REG || GET_CODE (dst) == SUBREG) + { +#if 1 || !defined(HANDLE_SUBREG) + if (use_dst) + df_uses_record (df, &SET_DEST (x), DF_REF_REG_USE, bb, insn); +#endif + df_uses_record (df, &SET_SRC (x), DF_REF_REG_USE, bb, insn); + return; + } + } + break; + + case RETURN: + break; + + case ASM_OPERANDS: + case UNSPEC_VOLATILE: + case TRAP_IF: + case ASM_INPUT: + { + /* Traditional and volatile asm instructions must be considered to use + and clobber all hard registers, all pseudo-registers and all of + memory. So must TRAP_IF and UNSPEC_VOLATILE operations. + + Consider for instance a volatile asm that changes the fpu rounding + mode. An insn should not be moved across this even if it only uses + pseudo-regs because it might give an incorrectly rounded result. + + For now, just mark any regs we can find in ASM_OPERANDS as + used. */ + + /* For all ASM_OPERANDS, we must traverse the vector of input operands. + We can not just fall through here since then we would be confused + by the ASM_INPUT rtx inside ASM_OPERANDS, which do not indicate + traditional asms unlike their normal usage. */ + if (code == ASM_OPERANDS) + { + int j; + + for (j = 0; j < ASM_OPERANDS_INPUT_LENGTH (x); j++) + df_uses_record (df, &ASM_OPERANDS_INPUT (x, j), + DF_REF_REG_USE, bb, insn); + } + break; + } + + case PRE_DEC: + case POST_DEC: + case PRE_INC: + case POST_INC: + case PRE_MODIFY: + case POST_MODIFY: + /* Catch the def of the register being modified. */ + df_ref_record (df, XEXP (x, 0), &XEXP (x, 0), bb, insn, DF_REF_REG_DEF); + + /* ... Fall through to handle uses ... */ + + default: + break; + } + + /* Recursively scan the operands of this expression. */ + { + register const char *fmt = GET_RTX_FORMAT (code); + int i; + + for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) + { + if (fmt[i] == 'e') + { + /* Tail recursive case: save a function call level. */ + if (i == 0) + { + loc = &XEXP (x, 0); + goto retry; + } + df_uses_record (df, &XEXP (x, i), ref_type, bb, insn); + } + else if (fmt[i] == 'E') + { + int j; + for (j = 0; j < XVECLEN (x, i); j++) + df_uses_record (df, &XVECEXP (x, i, j), ref_type, + bb, insn); + } + } + } +} + + +/* Record all the df within INSN of basic block BB. */ +static void +df_insn_refs_record (df, bb, insn) + struct df *df; + basic_block bb; + rtx insn; +{ + int i; + + if (INSN_P (insn)) + { + /* Record register defs */ + df_defs_record (df, PATTERN (insn), bb, insn); + + if (GET_CODE (insn) == CALL_INSN) + { + rtx note; + rtx x; + + /* Record the registers used to pass arguments. */ + for (note = CALL_INSN_FUNCTION_USAGE (insn); note; + note = XEXP (note, 1)) + { + if (GET_CODE (XEXP (note, 0)) == USE) + df_uses_record (df, &SET_DEST (XEXP (note, 0)), DF_REF_REG_USE, + bb, insn); + } + + /* The stack ptr is used (honorarily) by a CALL insn. */ + x = df_reg_use_gen (STACK_POINTER_REGNUM); + df_uses_record (df, &SET_DEST (x), DF_REF_REG_USE, bb, insn); + + if (df->flags & DF_HARD_REGS) + { + /* Calls may also reference any of the global registers, + so they are recorded as used. */ + for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) + if (global_regs[i]) + { + x = df_reg_use_gen (i); + df_uses_record (df, &SET_DEST (x), + DF_REF_REG_USE, bb, insn); + } + } + } + + /* Record the register uses. */ + df_uses_record (df, &PATTERN (insn), + DF_REF_REG_USE, bb, insn); + + + if (GET_CODE (insn) == CALL_INSN) + { + rtx note; + + if (df->flags & DF_HARD_REGS) + { + /* Each call clobbers all call-clobbered regs that are not + global or fixed and have not been explicitly defined + in the call pattern. */ + for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) + if (call_used_regs[i] + && ! global_regs[i] + && ! fixed_regs[i] + && ! df_insn_regno_def_p (df, bb, insn, i)) + { + rtx reg_clob = df_reg_clobber_gen (i); + df_defs_record (df, reg_clob, bb, insn); + } + } + + /* There may be extra registers to be clobbered. */ + for (note = CALL_INSN_FUNCTION_USAGE (insn); + note; + note = XEXP (note, 1)) + if (GET_CODE (XEXP (note, 0)) == CLOBBER) + df_defs_record (df, XEXP (note, 0), bb, insn); + } + } +} + + +/* Record all the refs within the basic block BB. */ +static void +df_bb_refs_record (df, bb) + struct df *df; + basic_block bb; +{ + rtx insn; + + /* Scan the block an insn at a time from beginning to end. */ + for (insn = bb->head; ; insn = NEXT_INSN (insn)) + { + if (INSN_P (insn)) + { + /* Record defs within INSN. */ + df_insn_refs_record (df, bb, insn); + } + if (insn == bb->end) + break; + } +} + + +/* Record all the refs in the basic blocks specified by BLOCKS. */ +static void +df_refs_record (df, blocks) + struct df *df; + bitmap blocks; +{ + basic_block bb; + + FOR_EACH_BB_IN_BITMAP (blocks, 0, bb, + { + df_bb_refs_record (df, bb); + }); +} + +/* Dataflow analysis routines. */ + + +/* Create reg-def chains for basic block BB. These are a list of + definitions for each register. */ +static void +df_bb_reg_def_chain_create (df, bb) + struct df *df; + basic_block bb; +{ + rtx insn; + + /* Perhaps the defs should be sorted using a depth first search + of the CFG (or possibly a breadth first search). We currently + scan the basic blocks in reverse order so that the first defs + apprear at the start of the chain. */ + + for (insn = bb->end; insn && insn != PREV_INSN (bb->head); + insn = PREV_INSN (insn)) + { + struct df_link *link; + unsigned int uid = INSN_UID (insn); + + if (! INSN_P (insn)) + continue; + + for (link = df->insns[uid].defs; link; link = link->next) + { + struct ref *def = link->ref; + unsigned int dregno = DF_REF_REGNO (def); + + df->regs[dregno].defs + = df_link_create (def, df->regs[dregno].defs); + } + } +} + + +/* Create reg-def chains for each basic block within BLOCKS. These + are a list of definitions for each register. */ +static void +df_reg_def_chain_create (df, blocks) + struct df *df; + bitmap blocks; +{ + basic_block bb; + + FOR_EACH_BB_IN_BITMAP/*_REV*/ (blocks, 0, bb, + { + df_bb_reg_def_chain_create (df, bb); + }); +} + + +/* Create reg-use chains for basic block BB. These are a list of uses + for each register. */ +static void +df_bb_reg_use_chain_create (df, bb) + struct df *df; + basic_block bb; +{ + rtx insn; + + /* Scan in forward order so that the last uses appear at the + start of the chain. */ + + for (insn = bb->head; insn && insn != NEXT_INSN (bb->end); + insn = NEXT_INSN (insn)) + { + struct df_link *link; + unsigned int uid = INSN_UID (insn); + + if (! INSN_P (insn)) + continue; + + for (link = df->insns[uid].uses; link; link = link->next) + { + struct ref *use = link->ref; + unsigned int uregno = DF_REF_REGNO (use); + + df->regs[uregno].uses + = df_link_create (use, df->regs[uregno].uses); + } + } +} + + +/* Create reg-use chains for each basic block within BLOCKS. These + are a list of uses for each register. */ +static void +df_reg_use_chain_create (df, blocks) + struct df *df; + bitmap blocks; +{ + basic_block bb; + + FOR_EACH_BB_IN_BITMAP (blocks, 0, bb, + { + df_bb_reg_use_chain_create (df, bb); + }); +} + + +/* Create def-use chains from reaching use bitmaps for basic block BB. */ +static void +df_bb_du_chain_create (df, bb, ru) + struct df *df; + basic_block bb; + bitmap ru; +{ + struct bb_info *bb_info = DF_BB_INFO (df, bb); + rtx insn; + + bitmap_copy (ru, bb_info->ru_out); + + /* For each def in BB create a linked list (chain) of uses + reached from the def. */ + for (insn = bb->end; insn && insn != PREV_INSN (bb->head); + insn = PREV_INSN (insn)) + { + struct df_link *def_link; + struct df_link *use_link; + unsigned int uid = INSN_UID (insn); + + if (! INSN_P (insn)) + continue; + + /* For each def in insn... */ + for (def_link = df->insns[uid].defs; def_link; def_link = def_link->next) + { + struct ref *def = def_link->ref; + unsigned int dregno = DF_REF_REGNO (def); + + DF_REF_CHAIN (def) = 0; + + /* While the reg-use chains are not essential, it + is _much_ faster to search these short lists rather + than all the reaching uses, especially for large functions. */ + for (use_link = df->regs[dregno].uses; use_link; + use_link = use_link->next) + { + struct ref *use = use_link->ref; + + if (bitmap_bit_p (ru, DF_REF_ID (use))) + { + DF_REF_CHAIN (def) + = df_link_create (use, DF_REF_CHAIN (def)); + + bitmap_clear_bit (ru, DF_REF_ID (use)); + } + } + } + + /* For each use in insn... */ + for (use_link = df->insns[uid].uses; use_link; use_link = use_link->next) + { + struct ref *use = use_link->ref; + bitmap_set_bit (ru, DF_REF_ID (use)); + } + } +} + + +/* Create def-use chains from reaching use bitmaps for basic blocks + in BLOCKS. */ +static void +df_du_chain_create (df, blocks) + struct df *df; + bitmap blocks; +{ + bitmap ru; + basic_block bb; + + ru = BITMAP_XMALLOC (); + + FOR_EACH_BB_IN_BITMAP (blocks, 0, bb, + { + df_bb_du_chain_create (df, bb, ru); + }); + + BITMAP_XFREE (ru); +} + + +/* Create use-def chains from reaching def bitmaps for basic block BB. */ +static void +df_bb_ud_chain_create (df, bb) + struct df *df; + basic_block bb; +{ + struct bb_info *bb_info = DF_BB_INFO (df, bb); + struct ref **reg_def_last = df->reg_def_last; + rtx insn; + + memset (reg_def_last, 0, df->n_regs * sizeof (struct ref *)); + + /* For each use in BB create a linked list (chain) of defs + that reach the use. */ + for (insn = bb->head; insn && insn != NEXT_INSN (bb->end); + insn = NEXT_INSN (insn)) + { + unsigned int uid = INSN_UID (insn); + struct df_link *use_link; + struct df_link *def_link; + + if (! INSN_P (insn)) + continue; + + /* For each use in insn... */ + for (use_link = df->insns[uid].uses; use_link; use_link = use_link->next) + { + struct ref *use = use_link->ref; + unsigned int regno = DF_REF_REGNO (use); + + DF_REF_CHAIN (use) = 0; + + /* Has regno been defined in this BB yet? If so, use + the last def as the single entry for the use-def + chain for this use. Otherwise, we need to add all + the defs using this regno that reach the start of + this BB. */ + if (reg_def_last[regno]) + { + DF_REF_CHAIN (use) + = df_link_create (reg_def_last[regno], 0); + } + else + { + /* While the reg-def chains are not essential, it is + _much_ faster to search these short lists rather than + all the reaching defs, especially for large + functions. */ + for (def_link = df->regs[regno].defs; def_link; + def_link = def_link->next) + { + struct ref *def = def_link->ref; + + if (bitmap_bit_p (bb_info->rd_in, DF_REF_ID (def))) + { + DF_REF_CHAIN (use) + = df_link_create (def, DF_REF_CHAIN (use)); + } + } + } + } + + + /* For each def in insn...record the last def of each reg. */ + for (def_link = df->insns[uid].defs; def_link; def_link = def_link->next) + { + struct ref *def = def_link->ref; + int dregno = DF_REF_REGNO (def); + + reg_def_last[dregno] = def; + } + } +} + + +/* Create use-def chains from reaching def bitmaps for basic blocks + within BLOCKS. */ +static void +df_ud_chain_create (df, blocks) + struct df *df; + bitmap blocks; +{ + basic_block bb; + + FOR_EACH_BB_IN_BITMAP (blocks, 0, bb, + { + df_bb_ud_chain_create (df, bb); + }); +} + + +/* Use depth first order, and the worklist, to figure out what block + to look at next. */ + +static int +df_visit_next (df, blocks) + struct df *df ATTRIBUTE_UNUSED; + sbitmap blocks; +{ + int i=0; + for (i = 0; i < n_basic_blocks; i++) + if (TEST_BIT (blocks, df->rc_order[i])) + return df->rc_order[i]; + return sbitmap_first_set_bit (blocks); +} + +/* Calculate reaching defs for each basic block in BLOCKS, i.e., the + defs that are live at the start of a basic block. */ +static void +df_rd_global_compute (df, blocks) + struct df *df ATTRIBUTE_UNUSED; + bitmap blocks; +{ + int i; + basic_block bb; + sbitmap worklist; + + worklist = sbitmap_alloc (n_basic_blocks); + sbitmap_zero (worklist); + + /* Copy the blocklist to the worklist */ + EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, + { + SET_BIT (worklist, i); + }); + + /* We assume that only the basic blocks in WORKLIST have been + modified. */ + FOR_EACH_BB_IN_SBITMAP (worklist, 0, bb, + { + struct bb_info *bb_info = DF_BB_INFO (df, bb); + + bitmap_copy (bb_info->rd_out, bb_info->rd_gen); + }); + + while ((i = df_visit_next (df, worklist)) >= 0) + { + struct bb_info *bb_info; + edge e; + int changed; + + /* Remove this block from the worklist. */ + RESET_BIT (worklist, i); + + + bb = BASIC_BLOCK (i); + bb_info = DF_BB_INFO (df, bb); + + /* Calculate union of predecessor outs. */ + bitmap_zero (bb_info->rd_in); + for (e = bb->pred; e != 0; e = e->pred_next) + { + struct bb_info *pred_refs = DF_BB_INFO (df, e->src); + + if (e->src == ENTRY_BLOCK_PTR) + continue; + + bitmap_a_or_b (bb_info->rd_in, bb_info->rd_in, + pred_refs->rd_out); + } + + /* RD_OUT is the set of defs that are live at the end of the + BB. These are the defs that are either generated by defs + (RD_GEN) within the BB or are live at the start (RD_IN) + and are not killed by other defs (RD_KILL). */ + changed = bitmap_union_of_diff (bb_info->rd_out, bb_info->rd_gen, + bb_info->rd_in, bb_info->rd_kill); + + if (changed) + { + /* Add each of this block's successors to the worklist. */ + for (e = bb->succ; e != 0; e = e->succ_next) + { + if (e->dest == EXIT_BLOCK_PTR) + continue; + + SET_BIT (worklist, i); + } + } + } + sbitmap_free (worklist); +} + + +/* Calculate reaching uses for each basic block within BLOCKS, i.e., + the uses that are live at the start of a basic block. */ +static void +df_ru_global_compute (df, blocks) + struct df *df ATTRIBUTE_UNUSED; + bitmap blocks; +{ + int i; + basic_block bb; + sbitmap worklist; + + worklist = sbitmap_alloc (n_basic_blocks); + sbitmap_zero (worklist); + + EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, + { + SET_BIT (worklist, i); + }); + + /* We assume that only the basic blocks in WORKLIST have been + modified. */ + FOR_EACH_BB_IN_SBITMAP (worklist, 0, bb, + { + struct bb_info *bb_info = DF_BB_INFO (df, bb); + + bitmap_copy (bb_info->ru_in, bb_info->ru_gen); + }); + + + while ((i = df_visit_next (df, worklist)) >= 0) + { + struct bb_info *bb_info; + edge e; + int changed; + + /* Remove this block from the worklist. */ + RESET_BIT (worklist, i); + + bb = BASIC_BLOCK (i); + bb_info = DF_BB_INFO (df, bb); + + /* Calculate union of successor ins. */ + bitmap_zero (bb_info->ru_out); + for (e = bb->succ; e != 0; e = e->succ_next) + { + struct bb_info *succ_refs = DF_BB_INFO (df, e->dest); + + if (e->dest == EXIT_BLOCK_PTR) + continue; + + bitmap_a_or_b (bb_info->ru_out, bb_info->ru_out, + succ_refs->ru_in); + } + + /* RU_IN is the set of uses that are live at the start of the + BB. These are the uses that are either generated within the + BB (RU_GEN) or are live at the end (RU_OUT) and are not uses + killed by defs within the BB (RU_KILL). */ + changed = bitmap_union_of_diff (bb_info->ru_in, bb_info->ru_gen, + bb_info->ru_out, bb_info->ru_kill); + + if (changed) + { + /* Add each of this block's predecessors to the worklist. */ + for (e = bb->pred; e != 0; e = e->pred_next) + { + if (e->src == ENTRY_BLOCK_PTR) + continue; + + SET_BIT (worklist, i); + } + } + } + + sbitmap_free (worklist); +} + + +/* Calculate live registers for each basic block within BLOCKS. */ +static void +df_lr_global_compute (df, blocks) + struct df *df ATTRIBUTE_UNUSED; + bitmap blocks; +{ + int i; + basic_block bb; + bitmap worklist; + + worklist = BITMAP_XMALLOC (); + bitmap_copy (worklist, blocks); + + /* We assume that only the basic blocks in WORKLIST have been + modified. */ + FOR_EACH_BB_IN_BITMAP (worklist, 0, bb, + { + struct bb_info *bb_info = DF_BB_INFO (df, bb); + + bitmap_copy (bb_info->lr_in, bb_info->lr_use); + }); + + while ((i = bitmap_last_set_bit (worklist)) >= 0) + { + struct bb_info *bb_info = DF_BB_INFO (df, bb); + edge e; + int changed; + + /* Remove this block from the worklist. */ + bitmap_clear_bit (worklist, i); + + bb = BASIC_BLOCK (i); + bb_info = DF_BB_INFO (df, bb); + + /* Calculate union of successor ins. */ + bitmap_zero (bb_info->lr_out); + for (e = bb->succ; e != 0; e = e->succ_next) + { + struct bb_info *succ_refs = DF_BB_INFO (df, e->dest); + + if (e->dest == EXIT_BLOCK_PTR) + continue; + + bitmap_a_or_b (bb_info->lr_out, bb_info->lr_out, + succ_refs->lr_in); + } + + /* LR_IN is the set of uses that are live at the start of the + BB. These are the uses that are either generated by uses + (LR_USE) within the BB or are live at the end (LR_OUT) + and are not killed by other uses (LR_DEF). */ + changed = bitmap_union_of_diff (bb_info->lr_in, bb_info->lr_use, + bb_info->lr_out, bb_info->lr_def); + + if (changed) + { + /* Add each of this block's predecessors to the worklist. */ + for (e = bb->pred; e != 0; e = e->pred_next) + { + if (e->src == ENTRY_BLOCK_PTR) + continue; + + bitmap_set_bit (worklist, e->src->index); + } + } + } + BITMAP_XFREE (worklist); +} + + +/* Compute local reaching def info for basic block BB. */ +static void +df_bb_rd_local_compute (df, bb) + struct df *df; + basic_block bb; +{ + struct bb_info *bb_info = DF_BB_INFO (df, bb); + rtx insn; + + for (insn = bb->head; insn && insn != NEXT_INSN (bb->end); + insn = NEXT_INSN (insn)) + { + unsigned int uid = INSN_UID (insn); + struct df_link *def_link; + + if (! INSN_P (insn)) + continue; + + for (def_link = df->insns[uid].defs; def_link; def_link = def_link->next) + { + struct ref *def = def_link->ref; + unsigned int regno = DF_REF_REGNO (def); + struct df_link *def2_link; + + for (def2_link = df->regs[regno].defs; def2_link; + def2_link = def2_link->next) + { + struct ref *def2 = def2_link->ref; + + /* Add all defs of this reg to the set of kills. This + is greedy since many of these defs will not actually + be killed by this BB but it keeps things a lot + simpler. */ + bitmap_set_bit (bb_info->rd_kill, DF_REF_ID (def2)); + + /* Zap from the set of gens for this BB. */ + bitmap_clear_bit (bb_info->rd_gen, DF_REF_ID (def2)); + } + + bitmap_set_bit (bb_info->rd_gen, DF_REF_ID (def)); + } + } + + bb_info->rd_valid = 1; +} + + +/* Compute local reaching def info for each basic block within BLOCKS. */ +static void +df_rd_local_compute (df, blocks) + struct df *df; + bitmap blocks; +{ + basic_block bb; + + FOR_EACH_BB_IN_BITMAP (blocks, 0, bb, + { + df_bb_rd_local_compute (df, bb); + }); +} + + +/* Compute local reaching use (upward exposed use) info for basic + block BB. */ +static void +df_bb_ru_local_compute (df, bb) + struct df *df; + basic_block bb; +{ + /* This is much more tricky than computing reaching defs. With + reaching defs, defs get killed by other defs. With upwards + exposed uses, these get killed by defs with the same regno. */ + + struct bb_info *bb_info = DF_BB_INFO (df, bb); + rtx insn; + + for (insn = bb->end; insn && insn != PREV_INSN (bb->head); + insn = PREV_INSN (insn)) + { + unsigned int uid = INSN_UID (insn); + struct df_link *def_link; + struct df_link *use_link; + + if (! INSN_P (insn)) + continue; + + for (def_link = df->insns[uid].defs; def_link; def_link = def_link->next) + { + struct ref *def = def_link->ref; + unsigned int dregno = DF_REF_REGNO (def); + + for (use_link = df->regs[dregno].uses; use_link; + use_link = use_link->next) + { + struct ref *use = use_link->ref; + + /* Add all uses of this reg to the set of kills. This + is greedy since many of these uses will not actually + be killed by this BB but it keeps things a lot + simpler. */ + bitmap_set_bit (bb_info->ru_kill, DF_REF_ID (use)); + + /* Zap from the set of gens for this BB. */ + bitmap_clear_bit (bb_info->ru_gen, DF_REF_ID (use)); + } + } + + for (use_link = df->insns[uid].uses; use_link; use_link = use_link->next) + { + struct ref *use = use_link->ref; + /* Add use to set of gens in this BB. */ + bitmap_set_bit (bb_info->ru_gen, DF_REF_ID (use)); + } + } + bb_info->ru_valid = 1; +} + + +/* Compute local reaching use (upward exposed use) info for each basic + block within BLOCKS. */ +static void +df_ru_local_compute (df, blocks) + struct df *df; + bitmap blocks; +{ + basic_block bb; + + FOR_EACH_BB_IN_BITMAP (blocks, 0, bb, + { + df_bb_ru_local_compute (df, bb); + }); +} + + +/* Compute local live variable info for basic block BB. */ +static void +df_bb_lr_local_compute (df, bb) + struct df *df; + basic_block bb; +{ + struct bb_info *bb_info = DF_BB_INFO (df, bb); + rtx insn; + + for (insn = bb->end; insn && insn != PREV_INSN (bb->head); + insn = PREV_INSN (insn)) + { + unsigned int uid = INSN_UID (insn); + struct df_link *link; + + if (! INSN_P (insn)) + continue; + + for (link = df->insns[uid].defs; link; link = link->next) + { + struct ref *def = link->ref; + unsigned int dregno = DF_REF_REGNO (def); + + /* Add def to set of defs in this BB. */ + bitmap_set_bit (bb_info->lr_def, dregno); + + bitmap_clear_bit (bb_info->lr_use, dregno); + } + + for (link = df->insns[uid].uses; link; link = link->next) + { + struct ref *use = link->ref; + /* Add use to set of uses in this BB. */ + bitmap_set_bit (bb_info->lr_use, DF_REF_REGNO (use)); + } + } + bb_info->lr_valid = 1; +} + + +/* Compute local live variable info for each basic block within BLOCKS. */ +static void +df_lr_local_compute (df, blocks) + struct df *df; + bitmap blocks; +{ + basic_block bb; + + FOR_EACH_BB_IN_BITMAP (blocks, 0, bb, + { + df_bb_lr_local_compute (df, bb); + }); +} + + +/* Compute register info: lifetime, bb, and number of defs and uses + for basic block BB. */ +static void +df_bb_reg_info_compute (df, bb, live) + struct df *df; + basic_block bb; + bitmap live; +{ + struct reg_info *reg_info = df->regs; + struct bb_info *bb_info = DF_BB_INFO (df, bb); + rtx insn; + + bitmap_copy (live, bb_info->lr_out); + + for (insn = bb->end; insn && insn != PREV_INSN (bb->head); + insn = PREV_INSN (insn)) + { + unsigned int uid = INSN_UID (insn); + unsigned int regno; + struct df_link *link; + + if (! INSN_P (insn)) + continue; + + for (link = df->insns[uid].defs; link; link = link->next) + { + struct ref *def = link->ref; + unsigned int dregno = DF_REF_REGNO (def); + + /* Kill this register. */ + bitmap_clear_bit (live, dregno); + reg_info[dregno].n_defs++; + } + + for (link = df->insns[uid].uses; link; link = link->next) + { + struct ref *use = link->ref; + unsigned int uregno = DF_REF_REGNO (use); + + /* This register is now live. */ + bitmap_set_bit (live, uregno); + reg_info[uregno].n_uses++; + } + + /* Increment lifetimes of all live registers. */ + EXECUTE_IF_SET_IN_BITMAP (live, 0, regno, + { + reg_info[regno].lifetime++; + }); + } +} + + +/* Compute register info: lifetime, bb, and number of defs and uses. */ +static void +df_reg_info_compute (df, blocks) + struct df *df; + bitmap blocks; +{ + basic_block bb; + bitmap live; + + live = BITMAP_XMALLOC (); + + FOR_EACH_BB_IN_BITMAP (blocks, 0, bb, + { + df_bb_reg_info_compute (df, bb, live); + }); + + BITMAP_XFREE (live); +} + + +/* Assign LUIDs for BB. */ +static int +df_bb_luids_set (df, bb) + struct df *df; + basic_block bb; +{ + rtx insn; + int luid = 0; + + /* The LUIDs are monotonically increasing for each basic block. */ + + for (insn = bb->head; ; insn = NEXT_INSN (insn)) + { + if (INSN_P (insn)) + DF_INSN_LUID (df, insn) = luid++; + DF_INSN_LUID (df, insn) = luid; + + if (insn == bb->end) + break; + } + return luid; +} + + +/* Assign LUIDs for each basic block within BLOCKS. */ +static int +df_luids_set (df, blocks) + struct df *df; + bitmap blocks; +{ + basic_block bb; + int total = 0; + + FOR_EACH_BB_IN_BITMAP (blocks, 0, bb, + { + total += df_bb_luids_set (df, bb); + }); + return total; +} + + +/* Perform dataflow analysis using existing DF structure for blocks + within BLOCKS. If BLOCKS is zero, use all basic blocks in the CFG. */ +static void +df_analyse_1 (df, blocks, flags, update) + struct df *df; + bitmap blocks; + int flags; + int update; +{ + int aflags; + int dflags; + + dflags = 0; + aflags = flags; + if (flags & DF_UD_CHAIN) + aflags |= DF_RD | DF_RD_CHAIN; + + if (flags & DF_DU_CHAIN) + aflags |= DF_RU; + + if (flags & DF_RU) + aflags |= DF_RU_CHAIN; + + if (flags & DF_REG_INFO) + aflags |= DF_LR; + + if (! blocks) + blocks = df->all_blocks; + + df->flags = flags; + if (update) + { + df_refs_update (df); + /* More fine grained incremental dataflow analysis would be + nice. For now recompute the whole shebang for the + modified blocks. */ +#if 0 + df_refs_unlink (df, blocks); +#endif + /* All the def-use, use-def chains can be potentially + modified by changes in one block. The size of the + bitmaps can also change. */ + } + else + { + /* Scan the function for all register defs and uses. */ + df_refs_queue (df); + df_refs_record (df, blocks); + + /* Link all the new defs and uses to the insns. */ + df_refs_process (df); + } + + /* Allocate the bitmaps now the total number of defs and uses are + known. If the number of defs or uses have changed, then + these bitmaps need to be reallocated. */ + df_bitmaps_alloc (df, aflags); + + /* Set the LUIDs for each specified basic block. */ + df_luids_set (df, blocks); + + /* Recreate reg-def and reg-use chains from scratch so that first + def is at the head of the reg-def chain and the last use is at + the head of the reg-use chain. This is only important for + regs local to a basic block as it speeds up searching. */ + if (aflags & DF_RD_CHAIN) + { + df_reg_def_chain_create (df, blocks); + } + + if (aflags & DF_RU_CHAIN) + { + df_reg_use_chain_create (df, blocks); + } + + df->dfs_order = xmalloc (sizeof(int) * n_basic_blocks); + df->rc_order = xmalloc (sizeof(int) * n_basic_blocks); + + flow_depth_first_order_compute (df->dfs_order, df->rc_order); + + if (aflags & DF_RD) + { + /* Compute the sets of gens and kills for the defs of each bb. */ + df_rd_local_compute (df, df->flags & DF_RD ? blocks : df->all_blocks); + + /* Compute the global reaching definitions. */ + df_rd_global_compute (df, df->all_blocks); + } + + if (aflags & DF_UD_CHAIN) + { + /* Create use-def chains. */ + df_ud_chain_create (df, df->all_blocks); + + if (! (flags & DF_RD)) + dflags |= DF_RD; + } + + if (aflags & DF_RU) + { + /* Compute the sets of gens and kills for the upwards exposed + uses in each bb. */ + df_ru_local_compute (df, df->flags & DF_RU ? blocks : df->all_blocks); + + /* Compute the global reaching uses. */ + df_ru_global_compute (df, df->all_blocks); + } + + if (aflags & DF_DU_CHAIN) + { + /* Create def-use chains. */ + df_du_chain_create (df, df->all_blocks); + + if (! (flags & DF_RU)) + dflags |= DF_RU; + } + + /* Free up bitmaps that are no longer required. */ + if (dflags) + df_bitmaps_free (df, dflags); + + if (aflags & DF_LR) + { + /* Compute the sets of defs and uses of live variables. */ + df_lr_local_compute (df, df->flags & DF_LR ? blocks : df->all_blocks); + + /* Compute the global live variables. */ + df_lr_global_compute (df, df->all_blocks); + } + + if (aflags & DF_REG_INFO) + { + df_reg_info_compute (df, df->all_blocks); + } + free (df->dfs_order); + free (df->rc_order); +} + + +/* Initialise dataflow analysis. */ +struct df * +df_init () +{ + struct df *df; + + df = xcalloc (1, sizeof (struct df)); + + /* Squirrel away a global for debugging. */ + ddf = df; + + return df; +} + + +/* Start queuing refs. */ +static int +df_refs_queue (df) + struct df *df; +{ + df->def_id_save = df->def_id; + df->use_id_save = df->use_id; + /* ???? Perhaps we should save current obstack state so that we can + unwind it. */ + return 0; +} + + +/* Process queued refs. */ +static int +df_refs_process (df) + struct df *df; +{ + unsigned int i; + + /* Build new insn-def chains. */ + for (i = df->def_id_save; i != df->def_id; i++) + { + struct ref *def = df->defs[i]; + unsigned int uid = DF_REF_INSN_UID (def); + + /* Add def to head of def list for INSN. */ + df->insns[uid].defs + = df_link_create (def, df->insns[uid].defs); + } + + /* Build new insn-use chains. */ + for (i = df->use_id_save; i != df->use_id; i++) + { + struct ref *use = df->uses[i]; + unsigned int uid = DF_REF_INSN_UID (use); + + /* Add use to head of use list for INSN. */ + df->insns[uid].uses + = df_link_create (use, df->insns[uid].uses); + } + return 0; +} + + +/* Update refs for basic block BB. */ +static int +df_bb_refs_update (df, bb) + struct df *df; + basic_block bb; +{ + rtx insn; + int count = 0; + + /* While we have to scan the chain of insns for this BB, we don't + need to allocate and queue a long chain of BB/INSN pairs. Using + a bitmap for insns_modified saves memory and avoids queuing + duplicates. */ + + for (insn = bb->head; ; insn = NEXT_INSN (insn)) + { + unsigned int uid; + + uid = INSN_UID (insn); + + if (bitmap_bit_p (df->insns_modified, uid)) + { + /* Delete any allocated refs of this insn. MPH, FIXME. */ + df_insn_refs_unlink (df, bb, insn); + + /* Scan the insn for refs. */ + df_insn_refs_record (df, bb, insn); + + + bitmap_clear_bit (df->insns_modified, uid); + count++; + } + if (insn == bb->end) + break; + } + return count; +} + + +/* Process all the modified/deleted insns that were queued. */ +static int +df_refs_update (df) + struct df *df; +{ + basic_block bb; + int count = 0; + + if ((unsigned int)max_reg_num () >= df->reg_size) + df_reg_table_realloc (df, 0); + + df_refs_queue (df); + + FOR_EACH_BB_IN_BITMAP (df->bbs_modified, 0, bb, + { + count += df_bb_refs_update (df, bb); + }); + + df_refs_process (df); + return count; +} + + +/* Return non-zero if any of the requested blocks in the bitmap + BLOCKS have been modified. */ +static int +df_modified_p (df, blocks) + struct df *df; + bitmap blocks; +{ + unsigned int j; + int update = 0; + + for (j = 0; j < df->n_bbs; j++) + if (bitmap_bit_p (df->bbs_modified, j) + && (! blocks || (blocks == (bitmap) -1) || bitmap_bit_p (blocks, j))) + { + update = 1; + break; + } + + return update; +} + + +/* Analyse dataflow info for the basic blocks specified by the bitmap + BLOCKS, or for the whole CFG if BLOCKS is zero, or just for the + modified blocks if BLOCKS is -1. */ +int +df_analyse (df, blocks, flags) + struct df *df; + bitmap blocks; + int flags; +{ + int update; + + /* We could deal with additional basic blocks being created by + rescanning everything again. */ + if (df->n_bbs && df->n_bbs != (unsigned int)n_basic_blocks) + abort (); + + update = df_modified_p (df, blocks); + if (update || (flags != df->flags)) + { + if (! blocks) + { + if (df->n_bbs) + { + /* Recompute everything from scratch. */ + df_free (df); + } + /* Allocate and initialise data structures. */ + df_alloc (df, max_reg_num ()); + df_analyse_1 (df, 0, flags, 0); + update = 1; + } + else + { + if (blocks == (bitmap) -1) + blocks = df->bbs_modified; + + if (! df->n_bbs) + abort (); + + df_analyse_1 (df, blocks, flags, 1); + bitmap_zero (df->bbs_modified); + } + } + return update; +} + + +/* Free all the dataflow info and the DF structure. */ +void +df_finish (df) + struct df *df; +{ + df_free (df); + free (df); +} + + +/* Unlink INSN from its reference information. */ +static void +df_insn_refs_unlink (df, bb, insn) + struct df *df; + basic_block bb ATTRIBUTE_UNUSED; + rtx insn; +{ + struct df_link *link; + unsigned int uid; + + uid = INSN_UID (insn); + + /* Unlink all refs defined by this insn. */ + for (link = df->insns[uid].defs; link; link = link->next) + df_def_unlink (df, link->ref); + + /* Unlink all refs used by this insn. */ + for (link = df->insns[uid].uses; link; link = link->next) + df_use_unlink (df, link->ref); + + df->insns[uid].defs = 0; + df->insns[uid].uses = 0; +} + + +/* Unlink all the insns within BB from their reference information. */ +static void +df_bb_refs_unlink (df, bb) + struct df *df; + basic_block bb; +{ + rtx insn; + + /* Scan the block an insn at a time from beginning to end. */ + for (insn = bb->head; ; insn = NEXT_INSN (insn)) + { + if (INSN_P (insn)) + { + /* Unlink refs for INSN. */ + df_insn_refs_unlink (df, bb, insn); + } + if (insn == bb->end) + break; + } +} + + +#if 0 +/* Unlink all the refs in the basic blocks specified by BLOCKS. + Not currently used. */ +static void +df_refs_unlink (df, blocks) + struct df *df; + bitmap blocks; +{ + basic_block bb; + + if (blocks) + { + FOR_EACH_BB_IN_BITMAP (blocks, 0, bb, + { + df_bb_refs_unlink (df, bb); + }); + } + else + { + FOR_ALL_BBS (bb, + { + df_bb_refs_unlink (df, bb); + }); + } +} +#endif + +/* Functions to modify insns. */ + + +/* Delete INSN and all its reference information. */ +rtx +df_insn_delete (df, bb, insn) + struct df *df; + basic_block bb ATTRIBUTE_UNUSED; + rtx insn; +{ + /* If the insn is a jump, we should perhaps call delete_insn to + handle the JUMP_LABEL? */ + + /* We should not be deleting the NOTE_INSN_BASIC_BLOCK or label. */ + if (insn == bb->head) + abort (); + if (insn == bb->end) + bb->end = PREV_INSN (insn); + + /* Delete the insn. */ + PUT_CODE (insn, NOTE); + NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED; + NOTE_SOURCE_FILE (insn) = 0; + + df_insn_modify (df, bb, insn); + + return NEXT_INSN (insn); +} + + +/* Mark that INSN within BB may have changed (created/modified/deleted). + This may be called multiple times for the same insn. There is no + harm calling this function if the insn wasn't changed; it will just + slow down the rescanning of refs. */ +void +df_insn_modify (df, bb, insn) + struct df *df; + basic_block bb; + rtx insn; +{ + unsigned int uid; + + uid = INSN_UID (insn); + + bitmap_set_bit (df->bbs_modified, bb->index); + bitmap_set_bit (df->insns_modified, uid); + +#if 0 + /* For incremental updating on the fly, perhaps we could make a copy + of all the refs of the original insn and turn them into + anti-refs. When df_refs_update finds these anti-refs, it annihilates + the original refs. If validate_change fails then these anti-refs + will just get ignored. */ + */ +#endif +} + + +typedef struct replace_args +{ + rtx match; + rtx replacement; + rtx insn; + int modified; +} replace_args; + + +/* Replace mem pointed to by PX with its associated pseudo register. + DATA is actually a pointer to a structure describing the + instruction currently being scanned and the MEM we are currently + replacing. */ +static int +df_rtx_mem_replace (px, data) + rtx *px; + void *data; +{ + replace_args *args = (replace_args *) data; + rtx mem = *px; + + if (mem == NULL_RTX) + return 0; + + switch (GET_CODE (mem)) + { + case MEM: + break; + + case CONST_DOUBLE: + /* We're not interested in the MEM associated with a + CONST_DOUBLE, so there's no need to traverse into one. */ + return -1; + + default: + /* This is not a MEM. */ + return 0; + } + + if (!rtx_equal_p (args->match, mem)) + /* This is not the MEM we are currently replacing. */ + return 0; + + /* Actually replace the MEM. */ + validate_change (args->insn, px, args->replacement, 1); + args->modified++; + + return 0; +} + + +int +df_insn_mem_replace (df, bb, insn, mem, reg) + struct df *df; + basic_block bb; + rtx insn; + rtx mem; + rtx reg; +{ + replace_args args; + + args.insn = insn; + args.match = mem; + args.replacement = reg; + args.modified = 0; + + /* Seach and replace all matching mems within insn. */ + for_each_rtx (&insn, df_rtx_mem_replace, &args); + + if (args.modified) + df_insn_modify (df, bb, insn); + + /* ???? FIXME. We may have a new def or one or more new uses of REG + in INSN. REG should be a new pseudo so it won't affect the + dataflow information that we currently have. We should add + the new uses and defs to INSN and then recreate the chains + when df_analyse is called. */ + return args.modified; +} + + +/* Replace one register with another. Called through for_each_rtx; PX + points to the rtx being scanned. DATA is actually a pointer to a + structure of arguments. */ +static int +df_rtx_reg_replace (px, data) + rtx *px; + void *data; +{ + rtx x = *px; + replace_args *args = (replace_args *) data; + + if (x == NULL_RTX) + return 0; + + if (x == args->match) + { + validate_change (args->insn, px, args->replacement, 1); + args->modified++; + } + + return 0; +} + + +/* Replace the reg within every ref on CHAIN that is within the set + BLOCKS of basic blocks with NEWREG. Also update the regs within + REG_NOTES. */ +void +df_refs_reg_replace (df, blocks, chain, oldreg, newreg) + struct df *df; + bitmap blocks; + struct df_link *chain; + rtx oldreg; + rtx newreg; +{ + struct df_link *link; + replace_args args; + + if (! blocks) + blocks = df->all_blocks; + + args.match = oldreg; + args.replacement = newreg; + args.modified = 0; + + for (link = chain; link; link = link->next) + { + struct ref *ref = link->ref; + rtx insn = DF_REF_INSN (ref); + + if (! INSN_P (insn)) + continue; + + if (bitmap_bit_p (blocks, DF_REF_BBNO (ref))) + { + df_ref_reg_replace (df, ref, oldreg, newreg); + + /* Replace occurrences of the reg within the REG_NOTES. */ + if ((! link->next || DF_REF_INSN (ref) + != DF_REF_INSN (link->next->ref)) + && REG_NOTES (insn)) + { + args.insn = insn; + for_each_rtx (®_NOTES (insn), df_rtx_reg_replace, &args); + } + } + else + { + /* Temporary check to ensure that we have a grip on which + regs should be replaced. */ + abort (); + } + } +} + + +/* Replace all occurrences of register OLDREG with register NEWREG in + blocks defined by bitmap BLOCKS. This also replaces occurrences of + OLDREG in the REG_NOTES but only for insns containing OLDREG. This + routine expects the reg-use and reg-def chains to be valid. */ +int +df_reg_replace (df, blocks, oldreg, newreg) + struct df *df; + bitmap blocks; + rtx oldreg; + rtx newreg; +{ + unsigned int oldregno = REGNO (oldreg); + + df_refs_reg_replace (df, blocks, df->regs[oldregno].defs, oldreg, newreg); + df_refs_reg_replace (df, blocks, df->regs[oldregno].uses, oldreg, newreg); + return 1; +} + + +/* Try replacing the reg within REF with NEWREG. Do not modify + def-use/use-def chains. */ +int +df_ref_reg_replace (df, ref, oldreg, newreg) + struct df *df; + struct ref *ref; + rtx oldreg; + rtx newreg; +{ + /* Check that insn was deleted by being converted into a NOTE. If + so ignore this insn. */ + if (! INSN_P (DF_REF_INSN (ref))) + return 0; + + if (oldreg && oldreg != DF_REF_REG (ref)) + abort (); + + if (! validate_change (DF_REF_INSN (ref), DF_REF_LOC (ref), newreg, 1)) + return 0; + + df_insn_modify (df, DF_REF_BB (ref), DF_REF_INSN (ref)); + return 1; +} + + +struct ref* +df_bb_def_use_swap (df, bb, def_insn, use_insn, regno) + struct df * df; + basic_block bb; + rtx def_insn; + rtx use_insn; + unsigned int regno; +{ + struct ref *def; + struct ref *use; + int def_uid; + int use_uid; + struct df_link *link; + + def = df_bb_insn_regno_first_def_find (df, bb, def_insn, regno); + if (! def) + return 0; + + use = df_bb_insn_regno_last_use_find (df, bb, use_insn, regno); + if (! use) + return 0; + + /* The USE no longer exists. */ + use_uid = INSN_UID (use_insn); + df_use_unlink (df, use); + df_ref_unlink (&df->insns[use_uid].uses, use); + + /* The DEF requires shifting so remove it from DEF_INSN + and add it to USE_INSN by reusing LINK. */ + def_uid = INSN_UID (def_insn); + link = df_ref_unlink (&df->insns[def_uid].defs, def); + link->ref = def; + link->next = df->insns[use_uid].defs; + df->insns[use_uid].defs = link; + +#if 0 + link = df_ref_unlink (&df->regs[regno].defs, def); + link->ref = def; + link->next = df->regs[regno].defs; + df->insns[regno].defs = link; +#endif + + DF_REF_INSN (def) = use_insn; + return def; +} + + +/* Record df between FIRST_INSN and LAST_INSN inclusive. All new + insns must be processed by this routine. */ +static void +df_insns_modify (df, bb, first_insn, last_insn) + struct df *df; + basic_block bb; + rtx first_insn; + rtx last_insn; +{ + rtx insn; + + for (insn = first_insn; ; insn = NEXT_INSN (insn)) + { + unsigned int uid; + + /* A non-const call should not have slipped through the net. If + it does, we need to create a new basic block. Ouch. The + same applies for a label. */ + if ((GET_CODE (insn) == CALL_INSN + && ! CONST_CALL_P (insn)) + || GET_CODE (insn) == CODE_LABEL) + abort (); + + uid = INSN_UID (insn); + + if (uid >= df->insn_size) + df_insn_table_realloc (df, 0); + + df_insn_modify (df, bb, insn); + + if (insn == last_insn) + break; + } +} + + +/* Emit PATTERN before INSN within BB. */ +rtx +df_pattern_emit_before (df, pattern, bb, insn) + struct df *df ATTRIBUTE_UNUSED; + rtx pattern; + basic_block bb; + rtx insn; +{ + rtx ret_insn; + rtx prev_insn = PREV_INSN (insn); + + /* We should not be inserting before the start of the block. */ + if (insn == bb->head) + abort (); + ret_insn = emit_insn_before (pattern, insn); + if (ret_insn == insn) + return ret_insn; + + df_insns_modify (df, bb, NEXT_INSN (prev_insn), ret_insn); + return ret_insn; +} + + +/* Emit PATTERN after INSN within BB. */ +rtx +df_pattern_emit_after (df, pattern, bb, insn) + struct df *df; + rtx pattern; + basic_block bb; + rtx insn; +{ + rtx ret_insn; + + ret_insn = emit_insn_after (pattern, insn); + if (ret_insn == insn) + return ret_insn; + + if (bb->end == insn) + bb->end = ret_insn; + + df_insns_modify (df, bb, NEXT_INSN (insn), ret_insn); + return ret_insn; +} + + +/* Emit jump PATTERN after INSN within BB. */ +rtx +df_jump_pattern_emit_after (df, pattern, bb, insn) + struct df *df; + rtx pattern; + basic_block bb; + rtx insn; +{ + rtx ret_insn; + + ret_insn = emit_jump_insn_after (pattern, insn); + if (ret_insn == insn) + return ret_insn; + + if (bb->end == insn) + bb->end = ret_insn; + + df_insns_modify (df, bb, NEXT_INSN (insn), ret_insn); + return ret_insn; +} + + +/* Move INSN within BB before BEFORE_INSN within BEFORE_BB. + + This function should only be used to move loop invariant insns + out of a loop where it has been proven that the def-use info + will still be valid. */ +rtx +df_insn_move_before (df, bb, insn, before_bb, before_insn) + struct df *df; + basic_block bb; + rtx insn; + basic_block before_bb; + rtx before_insn; +{ + struct df_link *link; + unsigned int uid; + + if (! bb) + return df_pattern_emit_before (df, insn, before_bb, before_insn); + + uid = INSN_UID (insn); + + /* Change bb for all df defined and used by this insn. */ + for (link = df->insns[uid].defs; link; link = link->next) + DF_REF_BB (link->ref) = before_bb; + for (link = df->insns[uid].uses; link; link = link->next) + DF_REF_BB (link->ref) = before_bb; + + /* The lifetimes of the registers used in this insn will be reduced + while the lifetimes of the registers defined in this insn + are likely to be increased. */ + + /* ???? Perhaps all the insns moved should be stored on a list + which df_analyse removes when it recalculates data flow. */ + + return emit_block_insn_before (insn, before_insn, before_bb); +} + +/* Functions to query dataflow information. */ + + +int +df_insn_regno_def_p (df, bb, insn, regno) + struct df *df; + basic_block bb ATTRIBUTE_UNUSED; + rtx insn; + unsigned int regno; +{ + unsigned int uid; + struct df_link *link; + + uid = INSN_UID (insn); + + for (link = df->insns[uid].defs; link; link = link->next) + { + struct ref *def = link->ref; + + if (DF_REF_REGNO (def) == regno) + return 1; + } + + return 0; +} + + +static int +df_def_dominates_all_uses_p (df, def) + struct df *df ATTRIBUTE_UNUSED; + struct ref *def; +{ + struct df_link *du_link; + + /* Follow def-use chain to find all the uses of this def. */ + for (du_link = DF_REF_CHAIN (def); du_link; du_link = du_link->next) + { + struct ref *use = du_link->ref; + struct df_link *ud_link; + + /* Follow use-def chain to check all the defs for this use. */ + for (ud_link = DF_REF_CHAIN (use); ud_link; ud_link = ud_link->next) + if (ud_link->ref != def) + return 0; + } + return 1; +} + + +int +df_insn_dominates_all_uses_p (df, bb, insn) + struct df *df; + basic_block bb ATTRIBUTE_UNUSED; + rtx insn; +{ + unsigned int uid; + struct df_link *link; + + uid = INSN_UID (insn); + + for (link = df->insns[uid].defs; link; link = link->next) + { + struct ref *def = link->ref; + + if (! df_def_dominates_all_uses_p (df, def)) + return 0; + } + + return 1; +} + + +/* Return non-zero if all DF dominates all the uses within the bitmap + BLOCKS. */ +static int +df_def_dominates_uses_p (df, def, blocks) + struct df *df ATTRIBUTE_UNUSED; + struct ref *def; + bitmap blocks; +{ + struct df_link *du_link; + + /* Follow def-use chain to find all the uses of this def. */ + for (du_link = DF_REF_CHAIN (def); du_link; du_link = du_link->next) + { + struct ref *use = du_link->ref; + struct df_link *ud_link; + + /* Only worry about the uses within BLOCKS. For example, + consider a register defined within a loop that is live at the + loop exits. */ + if (bitmap_bit_p (blocks, DF_REF_BBNO (use))) + { + /* Follow use-def chain to check all the defs for this use. */ + for (ud_link = DF_REF_CHAIN (use); ud_link; ud_link = ud_link->next) + if (ud_link->ref != def) + return 0; + } + } + return 1; +} + + +/* Return non-zero if all the defs of INSN within BB dominates + all the corresponding uses. */ +int +df_insn_dominates_uses_p (df, bb, insn, blocks) + struct df *df; + basic_block bb ATTRIBUTE_UNUSED; + rtx insn; + bitmap blocks; +{ + unsigned int uid; + struct df_link *link; + + uid = INSN_UID (insn); + + for (link = df->insns[uid].defs; link; link = link->next) + { + struct ref *def = link->ref; + + /* Only consider the defs within BLOCKS. */ + if (bitmap_bit_p (blocks, DF_REF_BBNO (def)) + && ! df_def_dominates_uses_p (df, def, blocks)) + return 0; + } + return 1; +} + + +/* Return the basic block that REG referenced in or NULL if referenced + in multiple basic blocks. */ +basic_block +df_regno_bb (df, regno) + struct df *df; + unsigned int regno; +{ + struct df_link *defs = df->regs[regno].defs; + struct df_link *uses = df->regs[regno].uses; + struct ref *def = defs ? defs->ref : 0; + struct ref *use = uses ? uses->ref : 0; + basic_block bb_def = def ? DF_REF_BB (def) : 0; + basic_block bb_use = use ? DF_REF_BB (use) : 0; + + /* Compare blocks of first def and last use. ???? FIXME. What if + the reg-def and reg-use lists are not correctly ordered. */ + return bb_def == bb_use ? bb_def : 0; +} + + +/* Return non-zero if REG used in multiple basic blocks. */ +int +df_reg_global_p (df, reg) + struct df *df; + rtx reg; +{ + return df_regno_bb (df, REGNO (reg)) != 0; +} + + +/* Return total lifetime (in insns) of REG. */ +int +df_reg_lifetime (df, reg) + struct df *df; + rtx reg; +{ + return df->regs[REGNO (reg)].lifetime; +} + + +/* Return non-zero if REG live at start of BB. */ +int +df_bb_reg_live_start_p (df, bb, reg) + struct df *df ATTRIBUTE_UNUSED; + basic_block bb; + rtx reg; +{ + struct bb_info *bb_info = DF_BB_INFO (df, bb); + +#ifdef ENABLE_CHECKING + if (! bb_info->lr_in) + abort (); +#endif + + return bitmap_bit_p (bb_info->lr_in, REGNO (reg)); +} + + +/* Return non-zero if REG live at end of BB. */ +int +df_bb_reg_live_end_p (df, bb, reg) + struct df *df ATTRIBUTE_UNUSED; + basic_block bb; + rtx reg; +{ + struct bb_info *bb_info = DF_BB_INFO (df, bb); + +#ifdef ENABLE_CHECKING + if (! bb_info->lr_in) + abort (); +#endif + + return bitmap_bit_p (bb_info->lr_out, REGNO (reg)); +} + + +/* Return -1 if life of REG1 before life of REG2, 1 if life of REG1 + after life of REG2, or 0, if the lives overlap. */ +int +df_bb_regs_lives_compare (df, bb, reg1, reg2) + struct df *df; + basic_block bb; + rtx reg1; + rtx reg2; +{ + unsigned int regno1 = REGNO (reg1); + unsigned int regno2 = REGNO (reg2); + struct ref *def1; + struct ref *use1; + struct ref *def2; + struct ref *use2; + + + /* The regs must be local to BB. */ + if (df_regno_bb (df, regno1) != bb + || df_regno_bb (df, regno2) != bb) + abort (); + + def2 = df_bb_regno_first_def_find (df, bb, regno2); + use1 = df_bb_regno_last_use_find (df, bb, regno1); + + if (DF_INSN_LUID (df, DF_REF_INSN (def2)) + > DF_INSN_LUID (df, DF_REF_INSN (use1))) + return -1; + + def1 = df_bb_regno_first_def_find (df, bb, regno1); + use2 = df_bb_regno_last_use_find (df, bb, regno2); + + if (DF_INSN_LUID (df, DF_REF_INSN (def1)) + > DF_INSN_LUID (df, DF_REF_INSN (use2))) + return 1; + + return 0; +} + + +/* Return last use of REGNO within BB. */ +static struct ref * +df_bb_regno_last_use_find (df, bb, regno) + struct df * df; + basic_block bb ATTRIBUTE_UNUSED; + unsigned int regno; +{ + struct df_link *link; + + /* This assumes that the reg-use list is ordered such that for any + BB, the last use is found first. However, since the BBs are not + ordered, the first use in the chain is not necessarily the last + use in the function. */ + for (link = df->regs[regno].uses; link; link = link->next) + { + struct ref *use = link->ref; + + if (DF_REF_BB (use) == bb) + return use; + } + return 0; +} + + +/* Return first def of REGNO within BB. */ +static struct ref * +df_bb_regno_first_def_find (df, bb, regno) + struct df * df; + basic_block bb ATTRIBUTE_UNUSED; + unsigned int regno; +{ + struct df_link *link; + + /* This assumes that the reg-def list is ordered such that for any + BB, the first def is found first. However, since the BBs are not + ordered, the first def in the chain is not necessarily the first + def in the function. */ + for (link = df->regs[regno].defs; link; link = link->next) + { + struct ref *def = link->ref; + + if (DF_REF_BB (def) == bb) + return def; + } + return 0; +} + + +/* Return first use of REGNO inside INSN within BB. */ +static struct ref * +df_bb_insn_regno_last_use_find (df, bb, insn, regno) + struct df * df; + basic_block bb ATTRIBUTE_UNUSED; + rtx insn; + unsigned int regno; +{ + unsigned int uid; + struct df_link *link; + + uid = INSN_UID (insn); + + for (link = df->insns[uid].uses; link; link = link->next) + { + struct ref *use = link->ref; + + if (DF_REF_REGNO (use) == regno) + return use; + } + + return 0; +} + + +/* Return first def of REGNO inside INSN within BB. */ +static struct ref * +df_bb_insn_regno_first_def_find (df, bb, insn, regno) + struct df * df; + basic_block bb ATTRIBUTE_UNUSED; + rtx insn; + unsigned int regno; +{ + unsigned int uid; + struct df_link *link; + + uid = INSN_UID (insn); + + for (link = df->insns[uid].defs; link; link = link->next) + { + struct ref *def = link->ref; + + if (DF_REF_REGNO (def) == regno) + return def; + } + + return 0; +} + + +/* Return insn using REG if the BB contains only a single + use and def of REG. */ +rtx +df_bb_single_def_use_insn_find (df, bb, insn, reg) + struct df * df; + basic_block bb; + rtx insn; + rtx reg; +{ + struct ref *def; + struct ref *use; + struct df_link *du_link; + + def = df_bb_insn_regno_first_def_find (df, bb, insn, REGNO (reg)); + + if (! def) + abort (); + + du_link = DF_REF_CHAIN (def); + + if (! du_link) + return NULL_RTX; + + use = du_link->ref; + + /* Check if def is dead. */ + if (! use) + return NULL_RTX; + + /* Check for multiple uses. */ + if (du_link->next) + return NULL_RTX; + + return DF_REF_INSN (use); +} + +/* Functions for debugging/dumping dataflow information. */ + + +/* Dump a def-use or use-def chain for REF to FILE. */ +static void +df_chain_dump (link, file) + struct df_link *link; + FILE *file; +{ + fprintf (file, "{ "); + for (; link; link = link->next) + { + fprintf (file, "%c%d ", + DF_REF_REG_DEF_P (link->ref) ? 'd' : 'u', + DF_REF_ID (link->ref)); + } + fprintf (file, "}"); +} + +static void +df_chain_dump_regno (link, file) + struct df_link *link; + FILE *file; +{ + fprintf (file, "{ "); + for (; link; link = link->next) + { + fprintf (file, "%c%d(%d) ", + DF_REF_REG_DEF_P (link->ref) ? 'd' : 'u', + DF_REF_ID (link->ref), + DF_REF_REGNO (link->ref)); + } + fprintf (file, "}"); +} + +/* Dump dataflow info. */ +void +df_dump (df, flags, file) + struct df *df; + int flags; + FILE *file; +{ + unsigned int i; + unsigned int j; + + if (! df || ! file) + return; + + fprintf (file, "\nDataflow summary:\n"); + fprintf (file, "n_regs = %d, n_defs = %d, n_uses = %d, n_bbs = %d\n", + df->n_regs, df->n_defs, df->n_uses, df->n_bbs); + + if (flags & DF_RD) + { + fprintf (file, "Reaching defs:\n"); + for (i = 0; i < df->n_bbs; i++) + { + basic_block bb = BASIC_BLOCK (i); + struct bb_info *bb_info = DF_BB_INFO (df, bb); + + if (! bb_info->rd_in) + continue; + + fprintf (file, "bb %d in \t", i); + dump_bitmap (file, bb_info->rd_in); + fprintf (file, "bb %d gen \t", i); + dump_bitmap (file, bb_info->rd_gen); + fprintf (file, "bb %d kill\t", i); + dump_bitmap (file, bb_info->rd_kill); + fprintf (file, "bb %d out \t", i); + dump_bitmap (file, bb_info->rd_out); + } + } + + if (flags & DF_UD_CHAIN) + { + fprintf (file, "Use-def chains:\n"); + for (j = 0; j < df->n_defs; j++) + { + if (df->defs[j]) + { + fprintf (file, "d%d bb %d luid %d insn %d reg %d ", + j, DF_REF_BBNO (df->defs[j]), + DF_INSN_LUID (df, DF_REF_INSN (df->defs[j])), + DF_REF_INSN_UID (df->defs[j]), + DF_REF_REGNO (df->defs[j])); + df_chain_dump (DF_REF_CHAIN (df->defs[j]), file); + fprintf (file, "\n"); + } + } + } + + if (flags & DF_RU) + { + fprintf (file, "Reaching uses:\n"); + for (i = 0; i < df->n_bbs; i++) + { + basic_block bb = BASIC_BLOCK (i); + struct bb_info *bb_info = DF_BB_INFO (df, bb); + + if (! bb_info->ru_in) + continue; + + fprintf (file, "bb %d in \t", i); + dump_bitmap (file, bb_info->ru_in); + fprintf (file, "bb %d gen \t", i); + dump_bitmap (file, bb_info->ru_gen); + fprintf (file, "bb %d kill\t", i); + dump_bitmap (file, bb_info->ru_kill); + fprintf (file, "bb %d out \t", i); + dump_bitmap (file, bb_info->ru_out); + } + } + + if (flags & DF_DU_CHAIN) + { + fprintf (file, "Def-use chains:\n"); + for (j = 0; j < df->n_uses; j++) + { + if (df->uses[j]) + { + fprintf (file, "u%d bb %d luid %d insn %d reg %d ", + j, DF_REF_BBNO (df->uses[j]), + DF_INSN_LUID (df, DF_REF_INSN (df->uses[j])), + DF_REF_INSN_UID (df->uses[j]), + DF_REF_REGNO (df->uses[j])); + df_chain_dump (DF_REF_CHAIN (df->uses[j]), file); + fprintf (file, "\n"); + } + } + } + + if (flags & DF_LR) + { + fprintf (file, "Live regs:\n"); + for (i = 0; i < df->n_bbs; i++) + { + basic_block bb = BASIC_BLOCK (i); + struct bb_info *bb_info = DF_BB_INFO (df, bb); + + if (! bb_info->lr_in) + continue; + + fprintf (file, "bb %d in \t", i); + dump_bitmap (file, bb_info->lr_in); + fprintf (file, "bb %d use \t", i); + dump_bitmap (file, bb_info->lr_use); + fprintf (file, "bb %d def \t", i); + dump_bitmap (file, bb_info->lr_def); + fprintf (file, "bb %d out \t", i); + dump_bitmap (file, bb_info->lr_out); + } + } + + if (flags & (DF_REG_INFO | DF_RD_CHAIN | DF_RU_CHAIN)) + { + struct reg_info *reg_info = df->regs; + + fprintf (file, "Register info:\n"); + for (j = 0; j < df->n_regs; j++) + { + if (((flags & DF_REG_INFO) + && (reg_info[j].n_uses || reg_info[j].n_defs)) + || ((flags & DF_RD_CHAIN) && reg_info[j].defs) + || ((flags & DF_RU_CHAIN) && reg_info[j].uses)) + { + fprintf (file, "reg %d", j); + if ((flags & DF_RD_CHAIN) && (flags & DF_RU_CHAIN)) + { + basic_block bb = df_regno_bb (df, j); + + if (bb) + fprintf (file, " bb %d", bb->index); + else + fprintf (file, " bb ?"); + } + if (flags & DF_REG_INFO) + { + fprintf (file, " life %d", reg_info[j].lifetime); + } + + if ((flags & DF_REG_INFO) || (flags & DF_RD_CHAIN)) + { + fprintf (file, " defs "); + if (flags & DF_REG_INFO) + fprintf (file, "%d ", reg_info[j].n_defs); + if (flags & DF_RD_CHAIN) + df_chain_dump (reg_info[j].defs, file); + } + + if ((flags & DF_REG_INFO) || (flags & DF_RU_CHAIN)) + { + fprintf (file, " uses "); + if (flags & DF_REG_INFO) + fprintf (file, "%d ", reg_info[j].n_uses); + if (flags & DF_RU_CHAIN) + df_chain_dump (reg_info[j].uses, file); + } + + fprintf (file, "\n"); + } + } + } + fprintf (file, "\n"); +} + + +void +df_insn_debug (df, insn, file) + struct df *df; + rtx insn; + FILE *file; +{ + unsigned int uid; + int bbi; + + uid = INSN_UID (insn); + if (uid >= df->insn_size) + return; + + if (df->insns[uid].defs) + bbi = DF_REF_BBNO (df->insns[uid].defs->ref); + else if (df->insns[uid].uses) + bbi = DF_REF_BBNO (df->insns[uid].uses->ref); + else + bbi = -1; + + fprintf (file, "insn %d bb %d luid %d defs ", + uid, bbi, DF_INSN_LUID (df, insn)); + df_chain_dump (df->insns[uid].defs, file); + fprintf (file, " uses "); + df_chain_dump (df->insns[uid].uses, file); + fprintf (file, "\n"); +} + +void +df_insn_debug_regno (df, insn, file) + struct df *df; + rtx insn; + FILE *file; +{ + unsigned int uid; + int bbi; + + uid = INSN_UID (insn); + if (uid >= df->insn_size) + return; + + if (df->insns[uid].defs) + bbi = DF_REF_BBNO (df->insns[uid].defs->ref); + else if (df->insns[uid].uses) + bbi = DF_REF_BBNO (df->insns[uid].uses->ref); + else + bbi = -1; + + fprintf (file, "insn %d bb %d luid %d defs ", + uid, bbi, DF_INSN_LUID (df, insn)); + df_chain_dump_regno (df->insns[uid].defs, file); + fprintf (file, " uses "); + df_chain_dump_regno (df->insns[uid].uses, file); + fprintf (file, "\n"); +} + +static void +df_regno_debug (df, regno, file) + struct df *df; + unsigned int regno; + FILE *file; +{ + if (regno >= df->reg_size) + return; + + fprintf (file, "reg %d life %d defs ", + regno, df->regs[regno].lifetime); + df_chain_dump (df->regs[regno].defs, file); + fprintf (file, " uses "); + df_chain_dump (df->regs[regno].uses, file); + fprintf (file, "\n"); +} + + +static void +df_ref_debug (df, ref, file) + struct df *df; + struct ref *ref; + FILE *file; +{ + fprintf (file, "%c%d ", + DF_REF_REG_DEF_P (ref) ? 'd' : 'u', + DF_REF_ID (ref)); + fprintf (file, "reg %d bb %d luid %d insn %d chain ", + DF_REF_REGNO (ref), + DF_REF_BBNO (ref), + DF_INSN_LUID (df, DF_REF_INSN (ref)), + INSN_UID (DF_REF_INSN (ref))); + df_chain_dump (DF_REF_CHAIN (ref), file); + fprintf (file, "\n"); +} + + +void +debug_df_insn (insn) + rtx insn; +{ + df_insn_debug (ddf, insn, stderr); + debug_rtx (insn); +} + + +void +debug_df_reg (reg) + rtx reg; +{ + df_regno_debug (ddf, REGNO (reg), stderr); +} + + +void +debug_df_regno (regno) + unsigned int regno; +{ + df_regno_debug (ddf, regno, stderr); +} + + +void +debug_df_ref (ref) + struct ref *ref; +{ + df_ref_debug (ddf, ref, stderr); +} + + +void +debug_df_defno (defno) + unsigned int defno; +{ + df_ref_debug (ddf, ddf->defs[defno], stderr); +} + + +void +debug_df_useno (defno) + unsigned int defno; +{ + df_ref_debug (ddf, ddf->uses[defno], stderr); +} + + +void +debug_df_chain (link) + struct df_link *link; +{ + df_chain_dump (link, stderr); + fputc ('\n', stderr); +} diff --git a/gcc/df.h b/gcc/df.h new file mode 100644 index 00000000000..c581c88d4b9 --- /dev/null +++ b/gcc/df.h @@ -0,0 +1,297 @@ +/* Form lists of pseudo register references for autoinc optimization + for GNU compiler. This is part of flow optimization. + Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc. + Contributed by Michael P. Hayes (m.hayes@elec.canterbury.ac.nz) + +This file is part of GNU CC. + +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. + +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. + +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. */ + + +#define DF_RD 1 /* Reaching definitions. */ +#define DF_RU 2 /* Reaching uses. */ +#define DF_LR 4 /* Live registers. */ +#define DF_DU_CHAIN 8 /* Def-use chain. */ +#define DF_UD_CHAIN 16 /* Use-def chain. */ +#define DF_REG_INFO 32 /* Register info. */ +#define DF_RD_CHAIN 64 /* Reg-def chain. */ +#define DF_RU_CHAIN 128 /* Reg-use chain. */ +#define DF_ALL 255 +#define DF_HARD_REGS 1024 + +enum df_ref_type {DF_REF_REG_DEF, DF_REF_REG_USE, DF_REF_REG_MEM_LOAD, + DF_REF_REG_MEM_STORE}; + +#define DF_REF_TYPE_NAMES {"def", "use", "mem load", "mem store"} + +/* ???> Perhaps all these data structures should be made private + to enforce the interface. */ + + +/* Link on a def-use or use-def chain. */ +struct df_link +{ + struct df_link *next; + struct ref *ref; +}; + + +/* Define a register reference structure. */ +struct ref +{ + rtx reg; /* The register referenced. */ + basic_block bb; /* BB containing ref. */ + rtx insn; /* Insn containing ref. */ + rtx *loc; /* Loc is the location of the reg. */ + struct df_link *chain; /* Head of def-use or use-def chain. */ + enum df_ref_type type; /* Type of ref. */ + int id; /* Ref index. */ +}; + + +/* One of these structures is allocated for every insn. */ +struct insn_info +{ + struct df_link *defs; /* Head of insn-def chain. */ + struct df_link *uses; /* Head of insn-use chain. */ + /* ???? The following luid field should be considerd private so that + we can change it on the fly to accomodate new insns? */ + int luid; /* Logical UID. */ +#if 0 + rtx insn; /* Backpointer to the insn. */ +#endif +}; + + +/* One of these structures is allocated for every reg. */ +struct reg_info +{ + struct df_link *defs; /* Head of reg-def chain. */ + struct df_link *uses; /* Head of reg-use chain. */ + int lifetime; + int n_defs; + int n_uses; +}; + + +/* One of these structures is allocated for every basic block. */ +struct bb_info +{ + /* Reaching def bitmaps have def_id elements. */ + bitmap rd_kill; + bitmap rd_gen; + bitmap rd_in; + bitmap rd_out; + /* Reaching use bitmaps have use_id elements. */ + bitmap ru_kill; + bitmap ru_gen; + bitmap ru_in; + bitmap ru_out; + /* Live variable bitmaps have n_regs elements. */ + bitmap lr_def; + bitmap lr_use; + bitmap lr_in; + bitmap lr_out; + int rd_valid; + int ru_valid; + int lr_valid; +}; + + +struct df +{ + int flags; /* Indicates what's recorded. */ + struct bb_info *bbs; /* Basic block table. */ + struct ref **defs; /* Def table, indexed by def_id. */ + struct ref **uses; /* Use table, indexed by use_id. */ + struct ref **reg_def_last; /* Indexed by regno. */ + struct reg_info *regs; /* Regs table, index by regno. */ + unsigned int reg_size; /* Size of regs table. */ + struct insn_info *insns; /* Insn table, indexed by insn UID. */ + unsigned int insn_size; /* Size of insn table. */ + unsigned int def_id; /* Next def ID. */ + unsigned int def_size; /* Size of def table. */ + unsigned int n_defs; /* Size of def bitmaps. */ + unsigned int use_id; /* Next use ID. */ + unsigned int use_size; /* Size of use table. */ + unsigned int n_uses; /* Size of use bitmaps. */ + unsigned int n_bbs; /* Number of basic blocks. */ + unsigned int n_regs; /* Number of regs. */ + unsigned int def_id_save; /* Saved next def ID. */ + unsigned int use_id_save; /* Saved next use ID. */ + bitmap insns_modified; /* Insns that (may) have changed. */ + bitmap bbs_modified; /* Blocks that (may) have changed. */ + bitmap all_blocks; /* All blocks in CFG. */ + /* The bitmap vector of dominators or NULL if not computed. + Ideally, this should be a pointer to a CFG object. */ + bitmap *dom; + int * dfs_order; + int * rc_order; +}; + + +struct df_map +{ + rtx old; + rtx new; +}; + + +#define DF_BB_INFO(REFS, BB) (&REFS->bbs[(BB)->index]) + + +/* Macros to access the elements within the ref structure. */ +#define DF_REF_REAL_REG(REF) (GET_CODE ((REF)->reg) == SUBREG \ + ? SUBREG_REG ((REF)->reg) : ((REF)->reg)) +#define DF_REF_REGNO(REF) REGNO (DF_REF_REAL_REG (REF)) +#define DF_REF_REAL_LOC(REF) (GET_CODE ((REF)->reg) == SUBREG \ + ? &SUBREG_REG ((REF)->reg) : ((REF)->loc)) +#ifdef OLD_DF_INTERFACE +#define DF_REF_REG(REF) DF_REF_REAL_REG(REF) +#define DF_REF_LOC(REF) DF_REF_REAL_LOC(REF) +#else +#define DF_REF_REG(REF) ((REF)->reg) +#define DF_REF_LOC(REF) ((REF)->loc) +#endif +#define DF_REF_BB(REF) ((REF)->bb) +#define DF_REF_BBNO(REF) ((REF)->bb->index) +#define DF_REF_INSN(REF) ((REF)->insn) +#define DF_REF_INSN_UID(REF) (INSN_UID ((REF)->insn)) +#define DF_REF_TYPE(REF) ((REF)->type) +#define DF_REF_CHAIN(REF) ((REF)->chain) +#define DF_REF_ID(REF) ((REF)->id) + +/* Macros to determine the reference type. */ + +#define DF_REF_REG_DEF_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_DEF) +#define DF_REF_REG_USE_P(REF) ((REF) && ! DF_REF_REG_DEF_P (REF)) +#define DF_REF_REG_MEM_STORE_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_MEM_STORE) +#define DF_REF_REG_MEM_LOAD_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_MEM_LOAD) +#define DF_REF_REG_MEM_P(REF) (DF_REF_REG_MEM_STORE_P (REF) \ + || DF_REF_REG_MEM_LOAD_P (REF)) + + +/* Macros to access the elements within the reg_info structure table. */ + +#define DF_REGNO_FIRST_DEF(DF, REGNUM) \ +((DF)->regs[REGNUM].defs ? (DF)->regs[REGNUM].defs->ref : 0) +#define DF_REGNO_LAST_USE(DF, REGNUM) \ +((DF)->regs[REGNUM].uses ? (DF)->regs[REGNUM].uses->ref : 0) + +#define DF_REGNO_FIRST_BB(DF, REGNUM) \ +(DF_REGNO_FIRST_DEF (DF, REGNUM) \ +? DF_REF_BB (DF_REGNO_FIRST_DEF (DF, REGNUM)) : 0) +#define DF_REGNO_LAST_BB(DF, REGNUM) \ +(DF_REGNO_LAST_USE (DF, REGNUM) \ +? DF_REF_BB (DF_REGNO_LAST_USE (DF, REGNUM)) : 0) + + +/* Macros to access the elements within the insn_info structure table. */ + +#define DF_INSN_LUID(DF, INSN) ((DF)->insns[INSN_UID (INSN)].luid) +#define DF_INSN_DEFS(DF, INSN) ((DF)->insns[INSN_UID (INSN)].defs) +#define DF_INSN_USES(DF, INSN) ((DF)->insns[INSN_UID (INSN)].uses) + + +/* Functions to build and analyse dataflow information. */ + +extern struct df *df_init PARAMS ((void)); + +extern int df_analyse PARAMS ((struct df *, bitmap, int)); + +extern void df_finish PARAMS ((struct df *)); + +extern void df_dump PARAMS ((struct df *, int, FILE *)); + +/* Functions to modify insns. */ + +extern void df_insn_modify PARAMS ((struct df *, basic_block, rtx)); + +extern rtx df_insn_delete PARAMS ((struct df *, basic_block, rtx)); + +extern rtx df_pattern_emit_before PARAMS ((struct df *, rtx, + basic_block, rtx)); + +extern rtx df_jump_pattern_emit_after PARAMS ((struct df *, rtx, + basic_block, rtx)); + +extern rtx df_pattern_emit_after PARAMS ((struct df *, rtx, + basic_block, rtx)); + +extern rtx df_insn_move_before PARAMS ((struct df *, basic_block, rtx, + basic_block, rtx)); + +extern int df_reg_replace PARAMS ((struct df *, bitmap, rtx, rtx)); + +extern int df_ref_reg_replace PARAMS ((struct df *, struct ref *, rtx, rtx)); + +extern int df_ref_remove PARAMS ((struct df *, struct ref *)); + +extern int df_insn_reg_replace PARAMS ((struct df *, basic_block, + rtx, rtx, rtx)); + +extern int df_insn_mem_replace PARAMS ((struct df *, basic_block, + rtx, rtx, rtx)); + +extern struct ref *df_bb_def_use_swap PARAMS ((struct df *, basic_block, + rtx, rtx, unsigned int)); + + +/* Functions to query dataflow information. */ + +extern basic_block df_regno_bb PARAMS((struct df *, unsigned int)); + +extern int df_reg_lifetime PARAMS ((struct df *, rtx)); + +extern int df_reg_global_p PARAMS ((struct df *, rtx)); + +extern int df_insn_regno_def_p PARAMS ((struct df *, + basic_block, rtx, unsigned int)); + +extern int df_insn_dominates_all_uses_p PARAMS ((struct df *, + basic_block, rtx)); + +extern int df_insn_dominates_uses_p PARAMS ((struct df *, basic_block, + rtx, bitmap)); + +extern int df_bb_reg_live_start_p PARAMS ((struct df *, basic_block, rtx)); + +extern int df_bb_reg_live_end_p PARAMS ((struct df *, basic_block, rtx)); + +extern int df_bb_regs_lives_compare PARAMS ((struct df *, basic_block, + rtx, rtx)); + +extern rtx df_bb_single_def_use_insn_find PARAMS((struct df *, basic_block, + rtx, rtx)); + + +/* Functions for debugging from GDB. */ + +extern void debug_df_insn PARAMS ((rtx)); + +extern void debug_df_regno PARAMS ((unsigned int)); + +extern void debug_df_reg PARAMS ((rtx)); + +extern void debug_df_defno PARAMS ((unsigned int)); + +extern void debug_df_useno PARAMS ((unsigned int)); + +extern void debug_df_ref PARAMS ((struct ref *)); + +extern void debug_df_chain PARAMS ((struct df_link *)); +extern void df_insn_debug PARAMS ((struct df *, rtx, FILE *)); +extern void df_insn_debug_regno PARAMS ((struct df *, rtx, FILE *)); diff --git a/gcc/flow.c b/gcc/flow.c index a18c6253873..ae0c58af872 100644 --- a/gcc/flow.c +++ b/gcc/flow.c @@ -458,7 +458,6 @@ static int flow_loop_entry_edges_find PARAMS ((basic_block, const sbitmap, edge **)); static int flow_loop_exit_edges_find PARAMS ((const sbitmap, edge **)); static int flow_loop_nodes_find PARAMS ((basic_block, basic_block, sbitmap)); -static int flow_depth_first_order_compute PARAMS ((int *, int *)); static void flow_dfs_compute_reverse_init PARAMS ((depth_first_search_ds)); static void flow_dfs_compute_reverse_add_bb @@ -8223,7 +8222,7 @@ flow_loop_nodes_find (header, latch, nodes) tries to get as far away from the starting point as quickly as possible. */ -static int +int flow_depth_first_order_compute (dfs_order, rc_order) int *dfs_order; int *rc_order; diff --git a/gcc/po/ChangeLog b/gcc/po/ChangeLog index 71c0435afe4..bd6e8c4ceab 100644 --- a/gcc/po/ChangeLog +++ b/gcc/po/ChangeLog @@ -1,3 +1,7 @@ +Thu Jun 28 16:11:30 2001 Jeffrey A Law (law@cygnus.com) + + * POTFILES.in: Add df.c and df.h + Tue Jun 19 08:03:43 2001 Jeffrey A Law (law@cygnus.com) * POTFILES.in: Replace dce.c with ssa-dce.c. diff --git a/gcc/po/POTFILES.in b/gcc/po/POTFILES.in index 20bebcf6257..12d1dd7ce2b 100644 --- a/gcc/po/POTFILES.in +++ b/gcc/po/POTFILES.in @@ -716,6 +716,8 @@ dbxout.h dbxstclass.h defaults.h dependence.c +df.c +df.h diagnostic.c diagnostic.h doloop.c