From 20805fb54aee0d0e337d53facf77a5c66f9f0c9c Mon Sep 17 00:00:00 2001
From: Andrew MacLeod <amacleod@redhat.com>
Date: Tue, 18 Oct 2022 16:29:49 -0400
Subject: [PATCH 1/3] Infer support

---
 gcc/gimple-range-infer.cc | 48 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/gcc/gimple-range-infer.cc b/gcc/gimple-range-infer.cc
index f0d66d047a6..95839445155 100644
--- a/gcc/gimple-range-infer.cc
+++ b/gcc/gimple-range-infer.cc
@@ -36,6 +36,25 @@ along with GCC; see the file COPYING3.  If not see
 #include "gimple-walk.h"
 #include "cfganal.h"
 
+
+// This routine needs to be provided to look up any ASSUME values
+// for name in ASSUME_ID.    Return TRUE if it has a value.
+
+bool
+query_assume_call (vrange &r, tree assume_id, tree name)
+{
+  if (dump_file)
+    fprintf (dump_file, "query_assume_call injection\n");
+  if (assume_id != NULL_TREE)
+    {
+      // Just return the global value until this can be provided.
+      gimple_range_global (r, name);
+      return true;
+    }
+  return false;
+}
+
+
 // Adapted from infer_nonnull_range_by_dereference and check_loadstore
 // to process nonnull ssa_name OP in S.  DATA contains a pointer to a
 // stmt range inference instance.
@@ -111,6 +130,35 @@ gimple_infer_range::gimple_infer_range (gimple *s)
       // Fallthru and walk load/store ops now.
     }
 
+  // Look for ASSUME calls, and call query_assume_call for each argument
+  // to determine if there is any inferred range to be had.
+  if (is_a<gcall *> (s) && gimple_call_internal_p (s)
+      && gimple_call_internal_fn (s) == IFN_ASSUME)
+    {
+      tree assume_id = gimple_call_arg (s, 0);
+      for (unsigned i = 1; i < gimple_call_num_args (s); i++)
+	{
+	  tree op = gimple_call_arg (s, i);
+	  tree type = TREE_TYPE (op);
+	  if (gimple_range_ssa_p (op) && Value_Range::supports_type_p (type))
+	    {
+	      Value_Range assume_range (type);
+	      if (query_assume_call (assume_range, assume_id, op))
+		{
+		  add_range (op, assume_range);
+		  if (dump_file)
+		    {
+		      print_generic_expr (dump_file, assume_id, TDF_SLIM);
+		      fprintf (dump_file, " assume inferred range of ");
+		      print_generic_expr (dump_file, op, TDF_SLIM);
+		      fprintf (dump_file, " to ");
+		      assume_range.dump (dump_file);
+		      fputc ('\n', dump_file);
+		    }
+		}
+	    }
+	}
+    }
   // Look for possible non-null values.
   if (flag_delete_null_pointer_checks && gimple_code (s) != GIMPLE_ASM
       && !gimple_clobber_p (s))
-- 
2.37.3