CbC/CbC_gcc: gcc/web.c comparison

comparison gcc/web.c @ 63:b7f97abdc517 gcc-4.6-20100522

update gcc from gcc-4.5.0 to gcc-4.6

author	ryoma <e075725@ie.u-ryukyu.ac.jp>
date	Mon, 24 May 2010 12:47:05 +0900
parents	77e2b8dfacca
children	f6334be47118

comparison

equal deleted inserted replaced

-:3c8a44c06a95
+:b7f97abdc517
 /* Web construction code for GNU compiler.
 Contributed by Jan Hubicka.
-Copyright (C) 2001, 2002, 2004, 2006, 2007, 2008
+Copyright (C) 2001, 2002, 2004, 2006, 2007, 2008, 2010
 Free Software Foundation, Inc.
 This file is part of GCC.
 GCC is free software; you can redistribute it and/or modify it under
 We don't split registers with REG_USERVAR set unless -fmessy-debugging
 is specified, because debugging information about such split variables
 is almost unusable.
 TODO
-- Add code to keep debugging up-to-date after splitting user variable
-pseudos.  This can be done by keeping track of all the pseudos used
-for the variable and using life analysis information before reload
-to determine which one is live and, in case more than one are live,
-choose the one with the latest definition.
-Other optimization passes can benefit from the infrastructure too.
 - We may use profile information and ignore infrequent use for the
 purpose of web unifying, inserting the compensation code later to
 implement full induction variable expansion for loops (currently
 we expand only if the induction variable is dead afterward, which
 is often the case).  */
 #include "obstack.h"
 #include "basic-block.h"
 #include "output.h"
 #include "df.h"
 #include "function.h"
+#include "insn-config.h"
+#include "recog.h"
 #include "timevar.h"
 #include "tree-pass.h"
-static rtx entry_register (struct web_entry *, df_ref, char *);
-static void replace_ref (df_ref, rtx);
 /* Find the root of unionfind tree (the representative of set).  */
 struct web_entry *
 unionfind_root (struct web_entry *element)
 return true;
 second->pred = first;
 return false;
 }
+/* For INSN, union all defs and uses that are linked by match_dup.
+FUN is the function that does the union.  */
+static void
+union_match_dups (rtx insn, struct web_entry *def_entry,
+		  struct web_entry *use_entry,
+		  bool (*fun) (struct web_entry *, struct web_entry *))
+{
+struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn);
+df_ref *use_link = DF_INSN_INFO_USES (insn_info);
+df_ref *def_link = DF_INSN_INFO_DEFS (insn_info);
+int i;
+extract_insn (insn);
+for (i = 0; i < recog_data.n_dups; i++)
+{
+int op = recog_data.dup_num[i];
+enum op_type type = recog_data.operand_type[op];
+df_ref *ref, *dupref;
+struct web_entry *entry;
+for (dupref = use_link; *dupref; dupref++)
+	if (DF_REF_LOC (*dupref) == recog_data.dup_loc[i])
+	  break;
+if (*dupref == NULL
+	  || DF_REF_REGNO (*dupref) < FIRST_PSEUDO_REGISTER)
+	continue;
+ref = type == OP_IN ? use_link : def_link;
+entry = type == OP_IN ? use_entry : def_entry;
+for (; *ref; ref++)
+	if (DF_REF_LOC (*ref) == recog_data.operand_loc[op])
+	  break;
+(*fun) (use_entry + DF_REF_ID (*dupref), entry + DF_REF_ID (*ref));
+}
+}
 /* For each use, all possible defs reaching it must come in the same
 register, union them.
-FUN is the function that does the union.  */
+FUN is the function that does the union.
+In USED, we keep the DF_REF_ID of the first uninitialized uses of a
+register, so that all uninitialized uses of the register can be
+combined into a single web.  We actually offset it by 2, because
+the values 0 and 1 are reserved for use by entry_register.  */
 void
 union_defs (df_ref use, struct web_entry *def_entry,
-	    struct web_entry *use_entry,
+	    unsigned int *used, struct web_entry *use_entry,
 	    bool (*fun) (struct web_entry *, struct web_entry *))
 {
 struct df_insn_info *insn_info = DF_REF_INSN_INFO (use);
 struct df_link *link = DF_REF_CHAIN (use);
-df_ref *use_link;
 df_ref *eq_use_link;
 df_ref *def_link;
 rtx set;
 if (insn_info)
 {
 rtx insn = insn_info->insn;
-use_link = DF_INSN_INFO_USES (insn_info);
 eq_use_link = DF_INSN_INFO_EQ_USES (insn_info);
 def_link = DF_INSN_INFO_DEFS (insn_info);
 set = single_set (insn);
 }
 else
 {
 /* An artificial use.  It links up with nothing.  */
-use_link = NULL;
 eq_use_link = NULL;
 def_link = NULL;
 set = NULL;
 }
-/* Some instructions may use match_dup for their operands.  In case the
+/* Union all occurrences of the same register in reg notes.  */
-operands are dead, we will assign them different pseudos, creating
-invalid instructions, so union all uses of the same operand for each
-insn.  */
-if (use_link)
-while (*use_link)
-{
-	if (use != *use_link
-	    && DF_REF_REAL_REG (use) == DF_REF_REAL_REG (*use_link))
-	  (*fun) (use_entry + DF_REF_ID (use),
-		  use_entry + DF_REF_ID (*use_link));
-	use_link++;
-}
 if (eq_use_link)
 while (*eq_use_link)
 {
 	if (use != *eq_use_link
 	      (*fun) (use_entry + DF_REF_ID (use),
 		      def_entry + DF_REF_ID (*def_link));
 	    def_link++;
 	  }
 }
+/* UD chains of uninitialized REGs are empty.  Keeping all uses of
+the same uninitialized REG in a single web is not necessary for
+correctness, since the uses are undefined, but it's wasteful to
+allocate one register or slot for each reference.  Furthermore,
+creating new pseudos for uninitialized references in debug insns
+(see PR 42631) causes -fcompare-debug failures.  We record the
+number of the first uninitialized reference we found, and merge
+with it any other uninitialized references to the same
+register.  */
+if (!link)
+{
+int regno = REGNO (DF_REF_REAL_REG (use));
+if (used[regno])
+	(*fun) (use_entry + DF_REF_ID (use), use_entry + used[regno] - 2);
+else
+	used[regno] = DF_REF_ID (use) + 2;
+}
 while (link)
 {
 (*fun) (use_entry + DF_REF_ID (use),
 	      def_entry + DF_REF_ID (link->ref));
 link = link->next;
 }
 /* Find the corresponding register for the given entry.  */
 static rtx
-entry_register (struct web_entry *entry, df_ref ref, char *used)
+entry_register (struct web_entry *entry, df_ref ref, unsigned int *used)
 {
 struct web_entry *root;
 rtx reg, newreg;
 /* Find the corresponding web and see if it has been visited.  */
 return root->reg;
 /* We are seeing this web for the first time, do the assignment.  */
 reg = DF_REF_REAL_REG (ref);
-/* In case the original register is already assigned, generate new one.  */
+/* In case the original register is already assigned, generate new
-if (!used[REGNO (reg)])
+one.  Since we use USED to merge uninitialized refs into a single
+web, we might found an element to be nonzero without our having
+used it.  Test for 1, because union_defs saves it for our use,
+and there won't be any use for the other values when we get to
+this point.  */
+if (used[REGNO (reg)] != 1)
 newreg = reg, used[REGNO (reg)] = 1;
-else if (REG_USERVAR_P (reg) && 0/*&& !flag_messy_debugging*/)
-{
-newreg = reg;
-if (dump_file)
-	fprintf (dump_file,
-		 "New web forced to keep reg=%i (user variable)\n",
-		 REGNO (reg));
-}
 else
 {
 newreg = gen_reg_rtx (GET_MODE (reg));
 REG_USERVAR_P (newreg) = REG_USERVAR_P (reg);
 REG_POINTER (newreg) = REG_POINTER (reg);
 web_main (void)
 {
 struct web_entry *def_entry;
 struct web_entry *use_entry;
 unsigned int max = max_reg_num ();
-char *used;
+unsigned int *used;
 basic_block bb;
 unsigned int uses_num = 0;
 rtx insn;
 df_set_flags (DF_NO_HARD_REGS + DF_EQ_NOTES);
 /* Assign ids to the uses.  */
 FOR_ALL_BB (bb)
 FOR_BB_INSNS (bb, insn)
 {
 unsigned int uid = INSN_UID (insn);
-if (INSN_P (insn))
+if (NONDEBUG_INSN_P (insn))
 	{
 	  df_ref *use_rec;
 	  for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
 	    {
 	      df_ref use = *use_rec;
 	}
 }
 /* Record the number of uses and defs at the beginning of the optimization.  */
 def_entry = XCNEWVEC (struct web_entry, DF_DEFS_TABLE_SIZE());
-used = XCNEWVEC (char, max);
+used = XCNEWVEC (unsigned, max);
 use_entry = XCNEWVEC (struct web_entry, uses_num);
 /* Produce the web.  */
 FOR_ALL_BB (bb)
 FOR_BB_INSNS (bb, insn)
 {
 unsigned int uid = INSN_UID (insn);
-if (INSN_P (insn))
+if (NONDEBUG_INSN_P (insn))
 	{
 	  df_ref *use_rec;
+	  union_match_dups (insn, def_entry, use_entry, unionfind_union);
 	  for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
 	    {
 	      df_ref use = *use_rec;
 	      if (DF_REF_REGNO (use) >= FIRST_PSEUDO_REGISTER)
-		union_defs (use, def_entry, use_entry, unionfind_union);
+		union_defs (use, def_entry, used, use_entry, unionfind_union);
 	    }
 	  for (use_rec = DF_INSN_UID_EQ_USES (uid); *use_rec; use_rec++)
 	    {
 	      df_ref use = *use_rec;
 	      if (DF_REF_REGNO (use) >= FIRST_PSEUDO_REGISTER)
-		union_defs (use, def_entry, use_entry, unionfind_union);
+		union_defs (use, def_entry, used, use_entry, unionfind_union);
 	    }
 	}
 }
 /* Update the instruction stream, allocating new registers for split pseudos
 in progress.  */
 FOR_ALL_BB (bb)
 FOR_BB_INSNS (bb, insn)
 {
 unsigned int uid = INSN_UID (insn);
-if (INSN_P (insn))
+if (NONDEBUG_INSN_P (insn))
 	{
 	  df_ref *use_rec;
 	  df_ref *def_rec;
 	  for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
 	    {

Mercurial > hg > CbC > CbC_gcc

comparison gcc/web.c @ 63:b7f97abdc517 gcc-4.6-20100522