Re: [Patch, reload, tentative, PR 71627] Tweak conditions in find_valid_class_1

[Senthil Kumar Selvaraj]

Bernd Schmidt writes:

> On 10/18/2016 02:15 PM, Senthil Kumar Selvaraj wrote:
>> Will do both the changes and re-run the reg tests. Ok for trunk if the
>> tests pass for x86_64-pc-linux and avr?
>>
> Probably but let's see the patch first.

How does this look?

Bootstrapped and reg tested x86_64-pc-linux on top of trunk@190252 with
the in_hard_reg_set_p patch backport - there were no failures. Also ran
regtests for avr on trunk, no failures there as well.

Ok to commit to trunk?

Regards
Senthil

gcc/ChangeLog:

2016-10-21  Senthil Kumar Selvaraj  <senthil_kumar.selva...@atmel.com>

        * reload.c (find_valid_class_1): Allow regclass if atleast one
        regno in class is ok. Compute and use rclass size based on
        actually available regnos for mode in rclass.

gcc/testsuite/ChangeLog:

2016-10-21  Senthil Kumar Selvaraj  <senthil_kumar.selva...@atmel.com>

        * gcc.target/avr/pr71627.c: New test.




diff --git gcc/reload.c gcc/reload.c
index 9a859e5..880099e 100644
--- gcc/reload.c
+++ gcc/reload.c
@@ -715,25 +715,23 @@ find_valid_class_1 (machine_mode outer ATTRIBUTE_UNUSED,
 
   for (rclass = 1; rclass < N_REG_CLASSES; rclass++)
     {
-      int bad = 0;
-      for (regno = 0; regno < FIRST_PSEUDO_REGISTER && !bad; regno++)
-       {
-         if (in_hard_reg_set_p (reg_class_contents[rclass], mode, regno)
-             && !HARD_REGNO_MODE_OK (regno, mode))
-           bad = 1;
-       }
-      
-      if (bad)
-       continue;
+      unsigned int computed_rclass_size = 0;
+
+      for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
+        {
+          if (in_hard_reg_set_p (reg_class_contents[rclass], mode, regno)
+              && (HARD_REGNO_MODE_OK (regno, mode)))
+            computed_rclass_size++;
+        }
 
       cost = register_move_cost (outer, (enum reg_class) rclass, dest_class);
 
-      if ((reg_class_size[rclass] > best_size
+      if ((computed_rclass_size > best_size
           && (best_cost < 0 || best_cost >= cost))
          || best_cost > cost)
        {
          best_class = (enum reg_class) rclass;
-         best_size = reg_class_size[rclass];
+         best_size = computed_rclass_size;
          best_cost = register_move_cost (outer, (enum reg_class) rclass,
                                          dest_class);
        }
diff --git gcc/testsuite/gcc.target/avr/pr71627.c 
gcc/testsuite/gcc.target/avr/pr71627.c
new file mode 100644
index 0000000..eaef3d2
--- /dev/null
+++ gcc/testsuite/gcc.target/avr/pr71627.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O1" } */
+
+
+extern volatile __memx const long  a, b, c, d, e, f;
+extern volatile long result;
+
+extern void vfunc (const char*, ...);
+
+void foo (void)
+{
+       result = a + b + c + d + e + f;
+       vfunc ("text", a, b, c, d, e, f, result);
+}