annotations up-to-date.
We require that for any copy operation where the RHS and LHS have
- a non-null memory tag that the memory tag be the same. It is OK
+ a non-null memory tag the memory tag be the same. It is OK
for one or both of the memory tags to be NULL.
We also require tracking if a variable is dereferenced in a load or
&& SSA_NAME_OCCURS_IN_ABNORMAL_PHI (orig))
return false;
- /* If DEST is an SSA_NAME that flows from an abnormal edge or if it
- represents a hard register, then it cannot be replaced. */
+ /* If DEST is an SSA_NAME that flows from an abnormal edge, then it
+ cannot be replaced. */
if (TREE_CODE (dest) == SSA_NAME
- && (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (dest)
- || DECL_HARD_REGISTER (SSA_NAME_VAR (dest))))
+ && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (dest))
return false;
/* Anything else is OK. */
return true;
}
+/* Similarly, but we know that we're propagating into an ASM_EXPR. */
+
+bool
+may_propagate_copy_into_asm (tree dest)
+{
+ /* Hard register operands of asms are special. Do not bypass. */
+ return !(TREE_CODE (dest) == SSA_NAME
+ && TREE_CODE (SSA_NAME_VAR (dest)) == VAR_DECL
+ && DECL_HARD_REGISTER (SSA_NAME_VAR (dest)));
+}
+
/* Given two SSA_NAMEs pointers ORIG and NEW such that we are copy
propagating NEW into ORIG, consolidate aliasing information so that
tree orig_sym = SSA_NAME_VAR (orig);
var_ann_t new_ann = var_ann (new_sym);
var_ann_t orig_ann = var_ann (orig_sym);
+ struct ptr_info_def *orig_ptr_info;
gcc_assert (POINTER_TYPE_P (TREE_TYPE (orig)));
gcc_assert (POINTER_TYPE_P (TREE_TYPE (new)));
== get_alias_set (TREE_TYPE (TREE_TYPE (orig_sym))));
#endif
- /* Merge type-based alias info. */
+ /* Synchronize the type tags. If both pointers had a tag and they
+ are different, then something has gone wrong. */
if (new_ann->type_mem_tag == NULL_TREE)
new_ann->type_mem_tag = orig_ann->type_mem_tag;
else if (orig_ann->type_mem_tag == NULL_TREE)
orig_ann->type_mem_tag = new_ann->type_mem_tag;
else
gcc_assert (new_ann->type_mem_tag == orig_ann->type_mem_tag);
-}
+
+ orig_ptr_info = SSA_NAME_PTR_INFO (orig);
+ if (orig_ptr_info && orig_ptr_info->name_mem_tag)
+ {
+ struct ptr_info_def *new_ptr_info = get_ptr_info (new);
+
+ if (new_ptr_info->name_mem_tag == NULL_TREE)
+ {
+ /* If ORIG had a name tag, it means that was dereferenced in
+ the code, and since pointer NEW will now replace every
+ occurrence of ORIG, we have to make sure that NEW has an
+ appropriate tag. If, NEW did not have a name tag, get it
+ from ORIG. */
+ memcpy (new_ptr_info, orig_ptr_info, sizeof (*new_ptr_info));
+ new_ptr_info->pt_vars = BITMAP_GGC_ALLOC ();
+ bitmap_copy (new_ptr_info->pt_vars, orig_ptr_info->pt_vars);
+ new_ptr_info->name_mem_tag = orig_ptr_info->name_mem_tag;
+ }
+ else
+ {
+ /* If NEW already had a name tag, nothing needs to be done.
+ Note that pointer NEW may actually have a different set of
+ pointed-to variables.
+
+ However, since NEW is being copy-propagated into ORIG, it must
+ always be true that the pointed-to set for pointer NEW is the
+ same, or a subset, of the pointed-to set for pointer ORIG. If
+ this isn't the case, we shouldn't have been able to do the
+ propagation of NEW into ORIG. */
+#if defined ENABLE_CHECKING
+ if (orig_ptr_info->pt_vars && new_ptr_info->pt_vars)
+ gcc_assert (bitmap_intersect_p (new_ptr_info->pt_vars,
+ orig_ptr_info->pt_vars));
+#endif
+ }
+ }
+}
/* Common code for propagate_value and replace_exp.