Remove CC0

This removes CC0 and all directly related infrastructure.

CC_STATUS, CC_STATUS_MDEP, CC_STATUS_MDEP_INIT, and NOTICE_UPDATE_CC
are deleted and poisoned.  CC0 is only deleted (some targets use that
name for something else).  HAVE_cc0 is automatically generated, and we
no longer will do that after this patch.

CC_STATUS_INIT is suggested in final.c to also be useful for ports that
are not CC0, and at least arm seems to use it for something.  So I am
leaving that alone, but most targets that have it could remove it.

2021-05-04  Segher Boessenkool  <segher@kernel.crashing.org>

	* caller-save.c: Remove CC0.
	* cfgcleanup.c: Remove CC0.
	* cfgrtl.c: Remove CC0.
	* combine.c: Remove CC0.
	* compare-elim.c: Remove CC0.
	* conditions.h: Remove CC0.
	* config/h8300/h8300.h: Remove CC0.
	* config/h8300/h8300-protos.h: Remove CC0.
	* config/h8300/peepholes.md: Remove CC0.
	* config/i386/x86-tune-sched.c: Remove CC0.
	* config/m68k/m68k.c: Remove CC0.
	* config/rl78/rl78.c: Remove CC0.
	* config/sparc/sparc.c: Remove CC0.
	* config/xtensa/xtensa.c: Remove CC0.
	(gen_conditional_move):  Use pc_rtx instead of cc0_rtx in a piece of
	RTL where that is used as a placeholder only.
	* cprop.c: Remove CC0.
	* cse.c: Remove CC0.
	* cselib.c: Remove CC0.
	* df-problems.c: Remove CC0.
	* df-scan.c: Remove CC0.
	* doc/md.texi: Remove CC0.  Adjust an example.
	* doc/rtl.texi: Remove CC0.  Adjust an example.
	* doc/tm.texi: Regenerate.
	* doc/tm.texi.in: Remove CC0.
	* emit-rtl.c: Remove CC0.
	* final.c: Remove CC0.
	* fwprop.c: Remove CC0.
	* gcse-common.c: Remove CC0.
	* gcse.c: Remove CC0.
	* genattrtab.c: Remove CC0.
	* genconfig.c: Remove CC0.
	* genemit.c: Remove CC0.
	* genextract.c: Remove CC0.
	* gengenrtl.c: Remove CC0.
	* genrecog.c: Remove CC0.
	* haifa-sched.c: Remove CC0.
	* ifcvt.c: Remove CC0.
	* ira-costs.c: Remove CC0.
	* ira.c: Remove CC0.
	* jump.c: Remove CC0.
	* loop-invariant.c: Remove CC0.
	* lra-constraints.c: Remove CC0.
	* lra-eliminations.c: Remove CC0.
	* optabs.c: Remove CC0.
	* postreload-gcse.c: Remove CC0.
	* postreload.c: Remove CC0.
	* print-rtl.c: Remove CC0.
	* read-rtl-function.c: Remove CC0.
	* reg-notes.def: Remove CC0.
	* reg-stack.c: Remove CC0.
	* reginfo.c: Remove CC0.
	* regrename.c: Remove CC0.
	* reload.c: Remove CC0.
	* reload1.c: Remove CC0.
	* reorg.c: Remove CC0.
	* resource.c: Remove CC0.
	* rtl.c: Remove CC0.
	* rtl.def: Remove CC0.
	* rtl.h: Remove CC0.
	* rtlanal.c: Remove CC0.
	* sched-deps.c: Remove CC0.
	* sched-rgn.c: Remove CC0.
	* shrink-wrap.c: Remove CC0.
	* simplify-rtx.c: Remove CC0.
	* system.h: Remove CC0.  Poison NOTICE_UPDATE_CC, CC_STATUS_MDEP_INIT,
	CC_STATUS_MDEP, and CC_STATUS.
	* target.def: Remove CC0.
	* valtrack.c: Remove CC0.
	* var-tracking.c: Remove CC0.

1 files changed, 0 insertions, 19 deletions

diff --git a/gcc/genconfig.c b/gcc/genconfig.c
index df02bfe..30ad61eb 100644
--- a/gcc/genconfig.c
+++ b/gcc/genconfig.c
@@ -32,7 +32,6 @@ along with GCC; see the file COPYING3.  If not see
 static int max_recog_operands;  /* Largest operand number seen.  */
 static int max_dup_operands;    /* Largest number of match_dup in any insn.  */
 static int max_clobbers_per_insn;
-static int have_cc0_flag;
 static int have_cmove_flag;
 static int have_cond_exec_flag;
 static int have_lo_sum_flag;
@@ -105,11 +104,6 @@ walk_insn_part (rtx part, int recog_p, int non_pc_set_src)
 	max_recog_operands = XINT (part, 0);
       return;
 
-    case CC0:
-      if (recog_p)
-	have_cc0_flag = 1;
-      return;
-
     case LO_SUM:
       if (recog_p)
 	have_lo_sum_flag = 1;
@@ -329,19 +323,6 @@ main (int argc, const char **argv)
   printf ("#define MAX_INSNS_PER_SPLIT %d\n", max_insns_per_split);
   printf ("#endif\n");
 
-  if (have_cc0_flag)
-    {
-      printf ("#define HAVE_cc0 1\n");
-      printf ("#define CC0_P(X) ((X) == cc0_rtx)\n");
-    }
-  else
-    {
-      /* We output CC0_P this way to make sure that X is declared
-	 somewhere.  */
-      printf ("#define HAVE_cc0 0\n");
-      printf ("#define CC0_P(X) ((X) ? 0 : 0)\n");
-    }
-
   if (have_cmove_flag)
     printf ("#define HAVE_conditional_move 1\n");
   else