Index: osprey/be/com/nystrom_alias_analyzer.cxx
===================================================================
--- osprey/be/com/nystrom_alias_analyzer.cxx    (revision 3595)
+++ osprey/be/com/nystrom_alias_analyzer.cxx    (working copy)
@@ -28,6 +28,7 @@
 #include "be_ipa_util.h"
 #include "ipa_be_summary.h"
 #include "ipa_be_read.h"
+#include "config_opt.h"

 extern BOOL Write_ALIAS_CGNODE_Map;

@@ -142,6 +143,18 @@
     tag1 = tmp;
   }

+  // triage, check if this pair of alias tag is force aliased.
+  if(tag1 < AA_force_tag_alias_before_dim1-1 ||
+     (tag1 == AA_force_tag_alias_before_dim1-1 &&
+      tag2 < AA_force_tag_alias_before_dim2)) {
+    return POSSIBLY_ALIASED;
+  }
+  if(tag2 < AA_force_tag_alias_before_dim1-1 ||
+     (tag2 == AA_force_tag_alias_before_dim1-1 &&
+      tag1 < AA_force_tag_alias_before_dim2)) {
+    return POSSIBLY_ALIASED;
+  }
+
   bool result;
   if (checkQueryFile((UINT32)Current_PU_Count(),tag1,tag2,result))
     return result ? POSSIBLY_ALIASED : NOT_ALIASED;
Index: osprey/common/com/config_opt.h
===================================================================
--- osprey/common/com/config_opt.h      (revision 3595)
+++ osprey/common/com/config_opt.h      (working copy)
@@ -210,6 +210,9 @@
 extern BOOL OPT_Enable_WHIRL_SSA;  // enable SSA on WHIRL
 extern BOOL OPT_Enable_BUILD_WHIRL_SSA; // enable build WSSA driect from WHIRL

+extern UINT32 AA_force_tag_alias_before_dim1;
+extern UINT32 AA_force_tag_alias_before_dim2;
+
 #endif
 #ifdef __cplusplus
 }
Index: osprey/common/com/config_opt.cxx
===================================================================
--- osprey/common/com/config_opt.cxx    (revision 3595)
+++ osprey/common/com/config_opt.cxx    (working copy)
@@ -335,6 +335,16 @@
 BOOL OPT_Enable_WHIRL_SSA = FALSE;  // SSA on WHIRL, disabled by default
 BOOL OPT_Enable_BUILD_WHIRL_SSA = FALSE;  // SSA on WHIRL, disabled by default

+// alias analyzer triage value
+// all alias tag value less than AA_force_tag_alias_before_dim1 is
+// aliased with all other alias tags.
+// all alias tag value less than AA_force_tag_alias_before_dim2 is
+// aliased with tag[AA_force_tag_alias_before_dim1-1]
+//
+// triage is find the first error alias tag pair.
+UINT32 AA_force_tag_alias_before_dim1 = 0;
+UINT32 AA_force_tag_alias_before_dim2 = UINT32_MAX;
+
 /***** Obsolete options *****/
 static BOOL Fprop_Limit_Set = FALSE;
 ^L
@@ -889,6 +899,14 @@
     0, 0, 0,   &OPT_Enable_BUILD_WHIRL_SSA,    NULL,
     "Enable building WHIRL SSA directly on WHIRL" },

+  { OVK_UINT32,  OV_INTERNAL,  TRUE, "aa_force_alias_dim1",            "",
+    0, 1, UINT32_MAX,  &AA_force_tag_alias_before_dim1, NULL,
+    "Triage option for alias analyzer" },
+
+  { OVK_UINT32,  OV_INTERNAL,  TRUE, "aa_force_alias_dim2",            "",
+    0, 0, UINT32_MAX,  &AA_force_tag_alias_before_dim2, NULL,
+    "Triage option for alias analyzer" },
+
   /* Obsolete options: */

   { OVK_OBSOLETE,      OV_INTERNAL,    FALSE, "global_limit",          NULL,