merge revision(s) dddc542e9b61b292d80a96d0d0efbbf58719e3be: [Backport #19476]

	[Bug #19476]: correct cache index computation for repetition (#7457)

	---
	 regexec.c                | 4 ++--
	 test/ruby/test_regexp.rb | 5 +++++
	 2 files changed, 7 insertions(+), 2 deletions(-)

1 files changed, 2 insertions, 2 deletions

diff --git a/regexec.c b/regexec.c
index 5f454ac8ef..20d50f4ddc 100644
--- a/regexec.c
+++ b/regexec.c
@@ -1248,10 +1248,10 @@ find_cache_index_table(regex_t* reg, OnigStackType *stk, OnigStackIndex *repeat_
   }
 
   if (range->upper == 0x7fffffff) {
-    return range->base_num + range->inner_num * range->lower + (is_inc ? 0 : 1) + item->num;
+    return range->base_num + range->inner_num * (range->lower - (is_inc ? 1 : 0)) + (is_inc ? 0 : 1) + item->num;
   }
 
-  return range->base_num + range->inner_num * range->lower + (range->inner_num + 1) * (count - range->lower) + item->num;
+  return range->base_num + range->inner_num * (range->lower - 1) + (range->inner_num + 1) * (count - range->lower + 1) + item->num;
 }
 
 static void