re PR tree-optimization/79345 (passing yet-uninitialized member as argument to base class constructor should warn (-Wunitialized))

PR tree-optimization/79345
	* gensupport.h (struct pattern_stats): Add min_scratch_opno field.
	* gensupport.c (get_pattern_stats_1) <case MATCH_SCRATCH>: Update it.
	(get_pattern_stats): Initialize it.
	* genemit.c (gen_expand): Verify match_scratch numbers come after
	match_operand/match_dup numbers.
	* config/i386/i386.md (<s>mul<mode>3_highpart): Swap match_dup and
	match_scratch numbers.
	* config/i386/sse.md (avx2_gathersi<mode>, avx2_gatherdi<mode>):
	Likewise.
	* config/s390/s390.md (trunctdsd2): Likewise.

From-SVN: r245833

gcc/ChangeLog

@@ -1,3 +1,17 @@
+2017-03-02  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/79345
+	* gensupport.h (struct pattern_stats): Add min_scratch_opno field.
+	* gensupport.c (get_pattern_stats_1) <case MATCH_SCRATCH>: Update it.
+	(get_pattern_stats): Initialize it.
+	* genemit.c (gen_expand): Verify match_scratch numbers come after
+	match_operand/match_dup numbers.
+	* config/i386/i386.md (<s>mul<mode>3_highpart): Swap match_dup and
+	match_scratch numbers.
+	* config/i386/sse.md (avx2_gathersi<mode>, avx2_gatherdi<mode>):
+	Likewise.
+	* config/s390/s390.md (trunctdsd2): Likewise.
+
 2017-03-02  Richard Biener  <rguenther@suse.de>
 
 	* wide-int.h (wide_int_storage::operator=): Implement in terms

gcc/config/i386/i386.md

@@ -7364,11 +7364,11 @@
 			   (match_operand:SWI48 1 "nonimmediate_operand"))
 			 (any_extend:<DWI>
 			   (match_operand:SWI48 2 "register_operand")))
-		       (match_dup 4))))
+		       (match_dup 3))))
-	      (clobber (match_scratch:SWI48 3))
+	      (clobber (match_scratch:SWI48 4))
 	      (clobber (reg:CC FLAGS_REG))])]
   ""
-  "operands[4] = GEN_INT (GET_MODE_BITSIZE (<MODE>mode));")
+  "operands[3] = GEN_INT (GET_MODE_BITSIZE (<MODE>mode));")
 
 (define_insn "*<s>muldi3_highpart_1"
   [(set (match_operand:DI 0 "register_operand" "=d")

gcc/config/i386/sse.md

@@ -18873,7 +18873,7 @@
 		   (unspec:VEC_GATHER_MODE
 		     [(match_operand:VEC_GATHER_MODE 1 "register_operand")
 		      (mem:<ssescalarmode>
-			(match_par_dup 7
+			(match_par_dup 6
 			  [(match_operand 2 "vsib_address_operand")
 			   (match_operand:<VEC_GATHER_IDXSI>
 			      3 "register_operand")
@@ -18881,10 +18881,10 @@
 		      (mem:BLK (scratch))
 		      (match_operand:VEC_GATHER_MODE 4 "register_operand")]
 		     UNSPEC_GATHER))
-	      (clobber (match_scratch:VEC_GATHER_MODE 6))])]
+	      (clobber (match_scratch:VEC_GATHER_MODE 7))])]
   "TARGET_AVX2"
 {
-  operands[7]
+  operands[6]
     = gen_rtx_UNSPEC (Pmode, gen_rtvec (3, operands[2], operands[3],
 					operands[5]), UNSPEC_VSIBADDR);
 })
@@ -18934,7 +18934,7 @@
 		   (unspec:VEC_GATHER_MODE
 		     [(match_operand:<VEC_GATHER_SRCDI> 1 "register_operand")
 		      (mem:<ssescalarmode>
-			(match_par_dup 7
+			(match_par_dup 6
 			  [(match_operand 2 "vsib_address_operand")
 			   (match_operand:<VEC_GATHER_IDXDI>
 			      3 "register_operand")
@@ -18942,10 +18942,10 @@
 		      (mem:BLK (scratch))
 		      (match_operand:<VEC_GATHER_SRCDI> 4 "register_operand")]
 		     UNSPEC_GATHER))
-	      (clobber (match_scratch:VEC_GATHER_MODE 6))])]
+	      (clobber (match_scratch:VEC_GATHER_MODE 7))])]
   "TARGET_AVX2"
 {
-  operands[7]
+  operands[6]
     = gen_rtx_UNSPEC (Pmode, gen_rtvec (3, operands[2], operands[3],
 					operands[5]), UNSPEC_VSIBADDR);
 })

gcc/config/s390/s390.md

@@ -5074,15 +5074,15 @@
 
 (define_expand "trunctdsd2"
   [(parallel
-    [(set (match_dup 3)
+    [(set (match_dup 2)
 	  (float_truncate:DD (match_operand:TD 1 "register_operand" "")))
      (unspec:DI [(const_int DFP_RND_PREP_FOR_SHORT_PREC)] UNSPEC_ROUND)
-     (clobber (match_scratch:TD 2 ""))])
+     (clobber (match_scratch:TD 3 ""))])
    (set (match_operand:SD 0 "register_operand" "")
-	(float_truncate:SD (match_dup 3)))]
+	(float_truncate:SD (match_dup 2)))]
   "TARGET_HARD_DFP"
 {
-  operands[3] = gen_reg_rtx (DDmode);
+  operands[2] = gen_reg_rtx (DDmode);
 })
 
 ;

gcc/genemit.c

@@ -448,6 +448,10 @@ gen_expand (md_rtx_info *info)
 
   /* Find out how many operands this function has.  */
   get_pattern_stats (&stats, XVEC (expand, 1));
+  if (stats.min_scratch_opno != -1
+      && stats.min_scratch_opno <= MAX (stats.max_opno, stats.max_dup_opno))
+    fatal_at (info->loc, "define_expand for %s needs to have match_scratch "
+			 "numbers above all other operands", XSTR (expand, 0));
 
   /* Output the function name and argument declarations.  */
   printf ("rtx\ngen_%s (", XSTR (expand, 0));
@@ -479,8 +483,6 @@ gen_expand (md_rtx_info *info)
      make a local variable.  */
   for (i = stats.num_generator_args; i <= stats.max_dup_opno; i++)
     printf ("  rtx operand%d;\n", i);
-  for (; i <= stats.max_scratch_opno; i++)
-    printf ("  rtx operand%d ATTRIBUTE_UNUSED;\n", i);
   printf ("  rtx_insn *_val = 0;\n");
   printf ("  start_sequence ();\n");
 
@@ -516,7 +518,7 @@ gen_expand (md_rtx_info *info)
 	 (unless we aren't going to use them at all).  */
       if (XVEC (expand, 1) != 0)
 	{
-	  for (i = 0; i < stats.num_operand_vars; i++)
+	  for (i = 0; i <= MAX (stats.max_opno, stats.max_dup_opno); i++)
 	    {
 	      printf ("    operand%d = operands[%d];\n", i, i);
 	      printf ("    (void) operand%d;\n", i);

gcc/gensupport.c

@@ -3000,6 +3000,10 @@ get_pattern_stats_1 (struct pattern_stats *stats, rtx x)
       break;
 
     case MATCH_SCRATCH:
+      if (stats->min_scratch_opno == -1)
+	stats->min_scratch_opno = XINT (x, 0);
+      else
+	stats->min_scratch_opno = MIN (stats->min_scratch_opno, XINT (x, 0));
       stats->max_scratch_opno = MAX (stats->max_scratch_opno, XINT (x, 0));
       break;
 
@@ -3032,6 +3036,7 @@ get_pattern_stats (struct pattern_stats *stats, rtvec pattern)
 
   stats->max_opno = -1;
   stats->max_dup_opno = -1;
+  stats->min_scratch_opno = -1;
   stats->max_scratch_opno = -1;
   stats->num_dups = 0;
 

gcc/gensupport.h

@@ -199,7 +199,8 @@ struct pattern_stats
   /* The largest match_dup, match_op_dup or match_par_dup number found.  */
   int max_dup_opno;
 
-  /* The largest match_scratch number found.  */
+  /* The smallest and largest match_scratch number found.  */
+  int min_scratch_opno;
   int max_scratch_opno;
 
   /* The number of times match_dup, match_op_dup or match_par_dup appears