[src] Optimized Class inspect_str hash cloning.

You may now perform shallow clones of hashes with the not-exported
parrot_hash_clone_pruneable() function; Class's inspect_str VTABLE now uses
this instead of cloning the hash manually.  The function may need a better
name, and we may consider exporting it.

This optimization improves Rakudo startup by 3.557% and should improve all
object reflection similarly.

git-svn-id: https://svn.parrot.org/parrot/trunk@47821 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

include/parrot/hash.h

@@ -365,6 +365,15 @@ Hash * parrot_create_hash(PARROT_INTERP,
         __attribute__nonnull__(4)
         __attribute__nonnull__(5);
 
+void parrot_hash_clone_prunable(PARROT_INTERP,
+    ARGIN(const Hash *hash),
+    ARGOUT(Hash *dest),
+    int deep)
+        __attribute__nonnull__(1)
+        __attribute__nonnull__(2)
+        __attribute__nonnull__(3)
+        FUNC_MODIFIES(*dest);
+
 PARROT_WARN_UNUSED_RESULT
 PARROT_PURE_FUNCTION
 int PMC_compare(PARROT_INTERP, ARGIN(PMC *a), ARGIN(PMC *b))
@@ -505,6 +514,10 @@ int STRING_compare_distinct_cs_enc(PARROT_INTERP,
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(compare) \
     , PARROT_ASSERT_ARG(keyhash))
+#define ASSERT_ARGS_parrot_hash_clone_prunable __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
+       PARROT_ASSERT_ARG(interp) \
+    , PARROT_ASSERT_ARG(hash) \
+    , PARROT_ASSERT_ARG(dest))
 #define ASSERT_ARGS_PMC_compare __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(a) \

src/hash.c

@@ -1451,6 +1451,14 @@ void
 parrot_hash_clone(PARROT_INTERP, ARGIN(const Hash *hash), ARGOUT(Hash *dest))
 {
     ASSERT_ARGS(parrot_hash_clone)
+    parrot_hash_clone_prunable(interp, hash, dest, 1);
+}
+
+void
+parrot_hash_clone_prunable(PARROT_INTERP, ARGIN(const Hash *hash),
+    ARGOUT(Hash *dest), int deep)
+{
+    ASSERT_ARGS(parrot_hash_clone_prunable)
     UINTVAL entries = hash->entries;
     UINTVAL i;
 
@@ -1474,7 +1482,10 @@ parrot_hash_clone(PARROT_INTERP, ARGIN(const Hash *hash), ARGOUT(Hash *dest))
             if (PMC_IS_NULL((PMC *)b->value))
                 valtmp = (void *)PMCNULL;
             else
-                valtmp = (void *)VTABLE_clone(interp, (PMC*)b->value);
+                if (deep)
+                    valtmp = (void *)VTABLE_clone(interp, (PMC*)b->value);
+                else
+                    valtmp = b->value;
             break;
 
           default:

src/pmc/class.pmc

@@ -1112,13 +1112,11 @@ Array of Class PMCs representing the direct parents of this class.
         if (found->vtable->base_type == enum_class_Hash) {
             /* for Hash return values, create and return a shallow
              * clone because the VTABLE_clone does a deep clone */
-            PMC * const hash  = Parrot_pmc_new(INTERP, enum_class_Hash);
-            PMC * const iter  = VTABLE_get_iter(INTERP, found);
-            while (VTABLE_get_bool(INTERP, iter)) {
-                STRING * const key   = VTABLE_shift_string(INTERP, iter);
-                PMC    * const value = VTABLE_get_pmc_keyed_str(INTERP, found, key);
-                VTABLE_set_pmc_keyed_str(INTERP, hash, key, value);
-            }
+            PMC * const hash = Parrot_pmc_new(INTERP, enum_class_Hash);
+            Hash       *src  = VTABLE_get_pointer(interp, found);
+            Hash       *dest = VTABLE_get_pointer(interp, hash);
+
+            parrot_hash_clone_prunable(interp, src, dest, 0);
 
             return hash;
         }