Assert that #pragma GCC unroll (USHRT_MAX - 1)
completely unrolls a loop with trip count 0xFFFE.
Initial effort to support complete-unrolling pragma #pragma unroll
gcc/testsuite/ChangeLog:
PR c++/91840
* c-c++-common/unroll-8.c: New test
asserting that #pragma GCC unroll (USHRT_MAX - 1)
completely unrolls a loop with trip count 0xFFFE.
Signed-off-by: Yueh-Shun Li <[email protected]>
---
gcc/testsuite/c-c++-common/unroll-8.c | 37 +++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
create mode 100644 gcc/testsuite/c-c++-common/unroll-8.c
diff --git a/gcc/testsuite/c-c++-common/unroll-8.c
b/gcc/testsuite/c-c++-common/unroll-8.c
new file mode 100644
index 00000000000..a2e59ffe51b
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/unroll-8.c
@@ -0,0 +1,37 @@
+/*
+ Unroll factor and trip count limit test
+
+ Ensure that #pragma GCC unroll <USHRT_MAX - 1>
+ completely unrolls a for-loop with trip count 0xFFFE
+*/
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-cunrolli-details
-fdump-rtl-loop2_unroll-details" } */
+
+/*
+ It takes ~5min to run on an Intel N200 processor.
+ Request 20min in case it runs slow.
+*/
+/* { dg-timeout-factor 4 } */
+/* { dg-require-effective-target run_expensive_tests } */
+
+#define __stringify_helper(x) #x
+#define __stringify(x) __stringify_helper(x)
+
+#define USHRT_MAX_MINUS_ONE (__SHRT_MAX__ << 1)
+
+extern void bar (int);
+
+int j;
+
+void test (void)
+{
+ /*
+ USHRT_MAX == __SHRT_MAX__ * 2 + 1
+ USHRT_MAX - 1 >= 0xFFFE
+ 0xFFFE == 65534
+ */
+ _Pragma (__stringify (GCC unroll USHRT_MAX_MINUS_ONE))
+ for (unsigned long i = 1; i <= 65534; ++i)
+ bar(i);
+ /* { dg-final { scan-tree-dump "34:.*: loop with 65534 iterations completely
unrolled" "cunrolli" } } */
+}
--
2.54.0
