Makefile.in (stupid.o): Update dependencies.

	* Makefile.in (stupid.o): Update dependencies.
	(global.o): Likewise.
	* global.c: Include reload.h
	(reg_becomes_live): New function.
	(reg_dies): New function.
	(build_insn_chain): New function.
	(global_alloc): Call build_insn_chain before calling reload.
	* reload.h (struct needs): New structure definition.
	(struct insn_chain): Likewise.
	(reload_insn_chain): Declare variable.
	(new_insn_chain): Declare function.
	* reload1.c (reload_startobj): New variable.
	(reload_insn_chain): New variable.
	(unused_insn_chains): New variable.
	(new_insn_chain): New function.
	(init_reload): Initialize reload_startobj, not reload_firstobj.
	(reload): Initialize reload_firstobj.
	Before returning, free everything on the reload_obstack.
	* stupid.c: Include insn-config.h, reload.h and basic-block.h.
	(reg_where_dead_chain, reg_where_born_exact, reg_where_born_clobber,
	current_chain): New variables.
	(reg_where_born): Delete variable.
	(REG_WHERE_BORN): New macro.
	(find_clobbered_regs): New function.
	(stupid_life_analysis): Don't allocate/free reg_where_born.
	Allocate and free reg_where_born_exact, reg_where_born_clobber,
	reg_where_dead_chain.
	Use REG_WHERE_BORN instead of reg_where_born.
	While processing the insns, build the reload_insn_chain with
	information about register lifetimes.
	(stupid_reg_compare): Use REG_WHERE_BORN instead of reg_where_born.
	(stupid_mark_refs): Replace arg INSN with arg CHAIN.  All callers
	changed.
	Compute and information about birth and death of pseudo registers in
	reg_where_dead_chain, reg_where_born_exact and reg_where_born_clobber.
	Delete code to set elements of reg_where_born.

From-SVN: r22862

gcc/ChangeLog

+Tue Oct  6 01:36:00 1998  Bernd Schmidt <crux@Pool.Informatik.RWTH-Aachen.DE>
+
+	* Makefile.in (stupid.o): Update dependencies.
+	(global.o): Likewise.
+
+	* global.c: Include reload.h
+	(reg_becomes_live): New function.
+	(reg_dies): New function.
+	(build_insn_chain): New function.
+	(global_alloc): Call build_insn_chain before calling reload.
+
+	* reload.h (struct needs): New structure definition.
+	(struct insn_chain): Likewise.
+	(reload_insn_chain): Declare variable.
+	(new_insn_chain): Declare function.
+
+
+	* reload1.c (reload_startobj): New variable.
+	(reload_insn_chain): New variable.
+	(unused_insn_chains): New variable.
+	(new_insn_chain): New function.
+	(init_reload): Initialize reload_startobj, not reload_firstobj.
+	(reload): Initialize reload_firstobj.
+	Before returning, free everything on the reload_obstack.
+
+	* stupid.c: Include insn-config.h, reload.h and basic-block.h.
+	(reg_where_dead_chain, reg_where_born_exact, reg_where_born_clobber,
+	current_chain): New variables.
+	(reg_where_born): Delete variable.
+	(REG_WHERE_BORN): New macro.
+	(find_clobbered_regs): New function.
+	(stupid_life_analysis): Don't allocate/free reg_where_born.
+	Allocate and free reg_where_born_exact, reg_where_born_clobber,
+	reg_where_dead_chain.
+	Use REG_WHERE_BORN instead of reg_where_born.
+	While processing the insns, build the reload_insn_chain with
+	information about register lifetimes.
+	(stupid_reg_compare): Use REG_WHERE_BORN instead of reg_where_born.
+	(stupid_mark_refs): Replace arg INSN with arg CHAIN.  All callers
+	changed.
+	Compute and information about birth and death of pseudo registers in
+	reg_where_dead_chain, reg_where_born_exact and reg_where_born_clobber.
+	Delete code to set elements of reg_where_born.	
+
 Mon Oct  5 22:34:30 1998  Alexandre Petit-Bianco  <apbianco@cygnus.com>
 
 	* tree.def (GOTO_EXPR): Modified documentation.

gcc/Makefile.in

@@ -1461,7 +1461,7 @@ jump.o : jump.c $(CONFIG_H) system.h $(RTL_H) flags.h hard-reg-set.h $(REGS_H) \
    insn-config.h insn-flags.h $(RECOG_H) $(EXPR_H) real.h except.h \
    toplev.h
 stupid.o : stupid.c $(CONFIG_H) system.h $(RTL_H) $(REGS_H) hard-reg-set.h \
-   flags.h toplev.h
+   $(BASIC_BLOCK_H) insn-config.h reload.h flags.h toplev.h
 
 cse.o : cse.c $(CONFIG_H) system.h $(RTL_H) $(REGS_H) hard-reg-set.h flags.h \
    real.h insn-config.h $(RECOG_H) $(EXPR_H) toplev.h output.h
@@ -1487,7 +1487,7 @@ local-alloc.o : local-alloc.c $(CONFIG_H) system.h $(RTL_H) flags.h \
    insn-attr.h toplev.h
 bitmap.o : bitmap.c $(CONFIG_H) system.h $(RTL_H) flags.h $(BASIC_BLOCK_H) \
    $(REGS_H)
-global.o : global.c $(CONFIG_H) system.h $(RTL_H) flags.h  \
+global.o : global.c $(CONFIG_H) system.h $(RTL_H) flags.h reload.h \
    $(BASIC_BLOCK_H) $(REGS_H) hard-reg-set.h insn-config.h output.h toplev.h
 varray.o : varray.c $(CONFIG_H) system.h varray.h $(RTL_H) $(TREE_H) bitmap.h
 

gcc/global.c

@@ -29,6 +29,7 @@ Boston, MA 02111-1307, USA.  */
 #include "basic-block.h"
 #include "regs.h"
 #include "insn-config.h"
+#include "reload.h"
 #include "output.h"
 #include "toplev.h"
 
@@ -268,6 +269,9 @@ static void mark_reg_death	PROTO((rtx));
 static void mark_reg_live_nc	PROTO((int, enum machine_mode));
 static void set_preference	PROTO((rtx, rtx));
 static void dump_conflicts	PROTO((FILE *));
+static void reg_becomes_live	PROTO((rtx, rtx));
+static void reg_dies		PROTO((int, enum machine_mode));
+static void build_insn_chain	PROTO((rtx));
 
 /* Perform allocation of pseudo-registers not allocated by local_alloc.
    FILE is a file to output debugging information on,
@@ -573,7 +577,10 @@ global_alloc (file)
 	 for the sake of debugging information.  */
   if (n_basic_blocks > 0)
 #endif
-    retval = reload (get_insns (), 1, file);
+    {
+      build_insn_chain (get_insns ());
+      retval = reload (get_insns (), 1, file);
+    }
 
   free (conflicts);
   return retval;
@@ -1648,6 +1655,135 @@ mark_elimination (from, to)
       }
 }
 
+/* Used for communication between the following functions.  Holds the
+   current life information.  */
+static regset live_relevant_regs;
+
+/* Record in live_relevant_regs that register REG became live.  This
+   is called via note_stores.  */
+static void
+reg_becomes_live (reg, setter)
+     rtx reg;
+     rtx setter ATTRIBUTE_UNUSED;
+{
+  int regno;
+
+  if (GET_CODE (reg) == SUBREG)
+    reg = SUBREG_REG (reg);
+
+  if (GET_CODE (reg) != REG)
+    return;
+  
+  regno = REGNO (reg);
+  if (regno < FIRST_PSEUDO_REGISTER)
+    {
+      int nregs = HARD_REGNO_NREGS (regno, GET_MODE (reg));
+      while (nregs-- > 0)
+	SET_REGNO_REG_SET (live_relevant_regs, regno++);
+    }
+  else if (reg_renumber[regno] >= 0)
+    SET_REGNO_REG_SET (live_relevant_regs, regno);
+}
+
+/* Record in live_relevant_regs that register REGNO died.  */
+static void
+reg_dies (regno, mode)
+     int regno;
+     enum machine_mode mode;
+{
+  if (regno < FIRST_PSEUDO_REGISTER)
+    {
+      int nregs = HARD_REGNO_NREGS (regno, mode);
+      while (nregs-- > 0)
+	CLEAR_REGNO_REG_SET (live_relevant_regs, regno++);
+    }
+  else
+    CLEAR_REGNO_REG_SET (live_relevant_regs, regno);
+}
+
+/* Walk the insns of the current function and build reload_insn_chain,
+   and record register life information.  */
+static void
+build_insn_chain (first)
+     rtx first;
+{
+  struct insn_chain **p = &reload_insn_chain;
+  struct insn_chain *prev = 0;
+  int b = 0;
+
+  live_relevant_regs = ALLOCA_REG_SET ();
+
+  for (; first; first = NEXT_INSN (first))
+    {
+      struct insn_chain *c;
+
+      if (first == basic_block_head[b])
+	{
+	  int i;
+	  CLEAR_REG_SET (live_relevant_regs);
+	  for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+	    if (REGNO_REG_SET_P (basic_block_live_at_start[b], i)
+		&& ! TEST_HARD_REG_BIT (eliminable_regset, i))
+	      SET_REGNO_REG_SET (live_relevant_regs, i);
+
+	  for (; i < max_regno; i++)
+	    if (reg_renumber[i] >= 0
+		&& REGNO_REG_SET_P (basic_block_live_at_start[b], i))
+	      SET_REGNO_REG_SET (live_relevant_regs, i);
+	}
+
+      if (GET_CODE (first) != NOTE && GET_CODE (first) != BARRIER)
+	{
+	  c = new_insn_chain ();
+	  c->prev = prev;
+	  prev = c;
+	  *p = c;
+	  p = &c->next;
+	  c->insn = first;
+	  c->block = b;
+
+	  COPY_REG_SET (c->live_before, live_relevant_regs);
+
+	  if (GET_RTX_CLASS (GET_CODE (first)) == 'i')
+	    {
+	      rtx link;
+
+	      /* Mark the death of everything that dies in this instruction.  */
+
+	      for (link = REG_NOTES (first); link; link = XEXP (link, 1))
+		if (REG_NOTE_KIND (link) == REG_DEAD
+		    && GET_CODE (XEXP (link, 0)) == REG)
+		  reg_dies (REGNO (XEXP (link, 0)), GET_MODE (XEXP (link, 0)));
+
+	      /* Mark everything born in this instruction as live.  */
+
+	      note_stores (PATTERN (first), reg_becomes_live);
+	    }
+
+	  /* Remember which registers are live at the end of the insn, before
+	     killing those with REG_UNUSED notes.  */
+	  COPY_REG_SET (c->live_after, live_relevant_regs);
+
+	  if (GET_RTX_CLASS (GET_CODE (first)) == 'i')
+	    {
+	      rtx link;
+
+	      /* Mark anything that is set in this insn and then unused as dying.  */
+
+	      for (link = REG_NOTES (first); link; link = XEXP (link, 1))
+		if (REG_NOTE_KIND (link) == REG_UNUSED
+		    && GET_CODE (XEXP (link, 0)) == REG)
+		  reg_dies (REGNO (XEXP (link, 0)), GET_MODE (XEXP (link, 0)));
+	    }
+	}
+
+      if (first == basic_block_end[b])
+	b++;
+    }
+  FREE_REG_SET (live_relevant_regs);
+  *p = 0;
+}
+
 /* Print debugging trace information if -greg switch is given,
    showing the information on which the allocation decisions are based.  */
 

gcc/reload.h

@@ -142,6 +142,81 @@ extern enum insn_code reload_in_optab[];
 extern enum insn_code reload_out_optab[];
 #endif
 
+struct needs
+{
+  /* [0] is normal, [1] is nongroup.  */
+  short regs[2][N_REG_CLASSES];
+  short groups[N_REG_CLASSES];
+};
+
+#if defined SET_HARD_REG_BIT && defined CLEAR_REG_SET
+/* This structure describes instructions which are relevant for reload.
+   Apart from all regular insns, this also includes CODE_LABELs, since they
+   must be examined for register elimination.  */
+struct insn_chain 
+{
+  /* Links to the neighbour instructions.  */
+  struct insn_chain *next, *prev;
+
+  /* Link through a chains set up by calculate_needs_all_insns, containing
+     all insns that need reloading.  */
+  struct insn_chain *next_need_reload;
+
+  /* The basic block this insn is in.  */
+  int block;
+  /* The rtx of the insn.  */
+  rtx insn;
+  /* Register life information: record all live hard registers, and all
+     live pseudos that have a hard register.
+     This information is recorded for the point immediately before the insn
+     (in live_before), and for the point within the insn at which all
+     outputs have just been written to (in live_after).  */
+  regset live_before;
+  regset live_after;
+
+  /* For each class, size of group of consecutive regs
+     that is needed for the reloads of this class.  */
+  char group_size[N_REG_CLASSES];
+  /* For each class, the machine mode which requires consecutive
+     groups of regs of that class.
+     If two different modes ever require groups of one class,
+     they must be the same size and equally restrictive for that class,
+     otherwise we can't handle the complexity.  */
+  enum machine_mode group_mode[N_REG_CLASSES];
+
+  /* Indicates if a register was counted against the need for
+     groups.  0 means it can count against max_nongroup instead.  */
+  HARD_REG_SET counted_for_groups;
+
+  /* Indicates if a register was counted against the need for
+     non-groups.  0 means it can become part of a new group.
+     During choose_reload_regs, 1 here means don't use this reg
+     as part of a group, even if it seems to be otherwise ok.  */
+  HARD_REG_SET counted_for_nongroups;
+
+  /* Indicates which registers have already been used for spills.  */
+  HARD_REG_SET used_spill_regs;
+
+  /* Describe the needs for reload registers of this insn.  */
+  struct needs need;
+
+  /* Nonzero if find_reloads said the insn requires reloading.  */
+  unsigned int need_reload:1;
+  /* Nonzero if eliminate_regs_in_insn said it requires eliminations.  */
+  unsigned int need_elim:1;
+  /* Nonzero if this insn was inserted by perform_caller_saves.  */
+  unsigned int is_caller_save_insn:1;
+};
+
+/* A chain of insn_chain structures to describe all non-note insns in
+   a function.  */
+extern struct insn_chain *reload_insn_chain;
+
+/* Allocate a new insn_chain structure.  */
+extern struct insn_chain *new_insn_chain	PROTO((void));
+
+#endif
+
 /* Functions from reload.c:  */
 
 /* Return a memory location that will be used to copy X in mode MODE.  

gcc/reload1.c

@@ -32,9 +32,9 @@ Boston, MA 02111-1307, USA.  */
 #include "flags.h"
 #include "expr.h"
 #include "regs.h"
+#include "basic-block.h"
 #include "reload.h"
 #include "recog.h"
-#include "basic-block.h"
 #include "output.h"
 #include "real.h"
 #include "toplev.h"
@@ -279,6 +279,13 @@ enum insn_code reload_out_optab[NUM_MACHINE_MODES];
    insn.  */
 
 struct obstack reload_obstack;
+
+/* Points to the beginning of the reload_obstack.  All insn_chain structures
+   are allocated first.  */
+char *reload_startobj;
+
+/* The point after all insn_chain structures.  Used to quickly deallocate
+   memory used while processing one insn.  */
 char *reload_firstobj;
 
 #define obstack_chunk_alloc xmalloc
@@ -286,6 +293,10 @@ char *reload_firstobj;
 
 /* List of labels that must never be deleted.  */
 extern rtx forced_labels;
+
+/* List of insn_chain instructions, one for every insn that reload needs to
+   examine.  */
+struct insn_chain *reload_insn_chain;
 
 /* This structure is used to record information about register eliminations.
    Each array entry describes one possible way of eliminating a register
@@ -461,7 +472,7 @@ init_reload ()
 
   /* Initialize obstack for our rtl allocation.  */
   gcc_obstack_init (&reload_obstack);
-  reload_firstobj = (char *) obstack_alloc (&reload_obstack, 0);
+  reload_startobj = (char *) obstack_alloc (&reload_obstack, 0);
 
   /* Decide which register class should be used when reloading
      addresses.  If we are using SMALL_REGISTER_CLASSES, and any
@@ -522,6 +533,32 @@ init_reload ()
     }
 }
 
+/* List of insn chains that are currently unused.  */
+static struct insn_chain *unused_insn_chains = 0;
+
+/* Allocate an empty insn_chain structure.  */
+struct insn_chain *
+new_insn_chain ()
+{
+  struct insn_chain *c;
+
+  if (unused_insn_chains == 0)
+    {
+      c = obstack_alloc (&reload_obstack, sizeof (struct insn_chain));
+      c->live_before = OBSTACK_ALLOC_REG_SET (&reload_obstack);
+      c->live_after = OBSTACK_ALLOC_REG_SET (&reload_obstack);
+    }
+  else
+    {
+      c = unused_insn_chains;
+      unused_insn_chains = c->next;
+    }
+  c->is_caller_save_insn = 0;
+  c->need_reload = 0;
+  c->need_elim = 0;
+  return c;
+}
+
 /* Global variables used by reload and its subroutines.  */
 
 /* Set during calculate_needs if an insn needs reloading.  */
@@ -605,6 +642,8 @@ reload (first, global, dumpfile)
 
   failure = 0;
 
+  reload_firstobj = (char *) obstack_alloc (&reload_obstack, 0);
+
   /* Enable find_equiv_reg to distinguish insns made by reload.  */
   reload_first_uid = get_max_uid ();
 
@@ -1217,7 +1256,9 @@ reload (first, global, dumpfile)
       if (size > STACK_CHECK_MAX_FRAME_SIZE)
 	warning ("frame size too large for reliable stack checking");
     }
-	
+
+  obstack_free (&reload_obstack, reload_startobj);
+
   /* Indicate that we no longer have known memory locations or constants.  */
   reg_equiv_constant = 0;
   reg_equiv_memory_loc = 0;