1 files changed, 29 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/crc-crc-reverse.c b/gcc/testsuite/gcc.dg/crc-crc-reverse.c
new file mode 100644
index 00000000000..3b959fe0d13
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/crc-crc-reverse.c
@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-crc-details" } */
+
+ #include <stdint.h>
+ uint32_t crc24_reverse(uint32_t crc, const uint8_t *data, uint8_t len)
+ {
+   uint32_t state = crc;
+   uint8_t i;
+
+   for (i = 0; i < len; i++) {
+       uint8_t n, cur = data[len - i - 1];
+
+       for (n = 0; n < 8; n++) {
+	   int top_bit = state >> 23;
+
+	   state = (state << 1) & 0xffffff;
+	   state |= top_bit ^ ((cur >> (7 - n)) & 1);
+	   if (top_bit)
+	     state ^= 0xb4c000;
+	 }
+     }
+
+   return state;
+ }
+
+/* { dg-final { scan-tree-dump "crc24_reverse function maybe calculates CRC and returns it." "crc"} } */
+/* { dg-final { scan-tree-dump "Return size is 32" "crc"} } */
+/* { dg-final { scan-tree-dump "Loop iteration number is 7" "crc"} } */
+/* { dg-final { scan-tree-dump "Bit forward" "crc"} } */
+\ No newline at end of file