From: Andrew MacLeod <amacleod@redhat.com>
Date: Mon, 8 Nov 2021 14:32:42 +0000 (-0500)
Subject: Don't calculate new values when using the private context callback.
X-Git-Tag: basepoints/gcc-13~3307
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0cd653bd2559701da9cc4c9bf51f22bdd68623b5;p=thirdparty%2Fgcc.git

Don't calculate new values when using the private context callback.

When using rangers private callback mechanism to provide context
to fold_stmt calls, we are only suppose to be using the cache in read
only mode, never calculate new values.

	gcc/
	PR tree-optimization/103122
	* gimple-range.cc (gimple_ranger::range_of_expr): Request the cache
	entry with "calulate new values" set to false.

	gcc/testsuite/
	* g++.dg/pr103122.C: New.
---

diff --git a/gcc/gimple-range.cc b/gcc/gimple-range.cc
index e1177b1c5e8f..87dba6e81d89 100644
--- a/gcc/gimple-range.cc
+++ b/gcc/gimple-range.cc
@@ -88,8 +88,8 @@ gimple_ranger::range_of_expr (irange &r, tree expr, gimple *stmt)
       if (!m_cache.get_global_range (r, expr))
         r = gimple_range_global (expr);
       // Pick up implied context information from the on-entry cache
-      // if current_bb is set.
-      if (current_bb && m_cache.block_range (tmp, current_bb, expr))
+      // if current_bb is set.  Do not attempt any new calculations.
+      if (current_bb && m_cache.block_range (tmp, current_bb, expr, false))
 	{
 	  r.intersect (tmp);
 	  char str[80];
diff --git a/gcc/testsuite/g++.dg/pr103122.C b/gcc/testsuite/g++.dg/pr103122.C
new file mode 100644
index 000000000000..3465eade46bd
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr103122.C
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+unsigned a;
+int b;
+short c;
+void d(long) {
+  for (bool e = (bool)c - 1; e < (bool)b - 1; e += 0)
+    ;
+  if (a) {
+    for (char f = 0; f < 7; f = 7)
+      for (int g = 0; g < c; g += 10)
+        ;
+    d(-!c);
+  }
+}