Added propagation of not big initial stack size of master thread to workers.

Currently implemented only for non-Windows 64-bit platforms.

Differential Revision: https://reviews.llvm.org/D62488

llvm-svn: 362618

1 files changed, 65 insertions, 0 deletions

diff --git a/openmp/runtime/test/misc_bugs/stack-propagate.c b/openmp/runtime/test/misc_bugs/stack-propagate.c
new file mode 100644
index 00000000000..ac289b56ccd
--- /dev/null
+++ b/openmp/runtime/test/misc_bugs/stack-propagate.c
@@ -0,0 +1,65 @@
+// RUN: %libomp-compile-and-run
+
+// https://bugs.llvm.org/show_bug.cgi?id=26540 requested
+// stack size to be propagated from master to workers.
+// Library implements propagation of not too big stack
+// for Linux x86_64 platform (skipped Windows for now).
+//
+// The test checks that workers can use more than 4MB
+// of stack (4MB - was historical default for
+// stack size of worker thread in runtime library).
+
+#include <stdio.h>
+#include <omp.h>
+#if !defined(_WIN32)
+#include <sys/resource.h> // getrlimit
+#endif
+
+#define STK 4800000
+
+double foo(int n, int th)
+{
+  double arr[n];
+  int i;
+  double res = 0.0;
+  for (i = 0; i < n; ++i) {
+    arr[i] = (double)i / (n + 2);
+  }
+  for (i = 0; i < n; ++i) {
+    res += arr[i] / n;
+  }
+  return res;
+}
+
+int main(int argc, char *argv[])
+{
+#if defined(_WIN32)
+  // don't test Windows
+  printf("stack propagation not implemented, skipping test...\n");
+  return 0;
+#else
+  int status;
+  double val = 0.0;
+  int m = STK / 8; // > 4800000 bytes per thread
+  // read stack size of calling thread, save it as default
+  struct rlimit rlim;
+  status = getrlimit(RLIMIT_STACK, &rlim);
+  if (sizeof(void *) > 4 &&                 // do not test 32-bit systems,
+      status == 0 && rlim.rlim_cur > STK) { // or small initial stack size
+#pragma omp parallel reduction(+:val)
+    {
+      val += foo(m, omp_get_thread_num());
+    }
+  } else {
+    printf("too small stack size limit (needs about 8MB), skipping test...\n");
+    return 0;
+  }
+  if (val > 0.1) {
+    printf("passed\n");
+    return 0;
+  } else {
+    printf("failed, val = %f\n", val);
+    return 1;
+  }
+#endif // _WIN32
+}