===================================================================
@@ -1340,7 +1340,7 @@ allocate_dynamic_stack_space (rtx size,
least it doesn't cause a stack overflow. */
if (flag_split_stack)
{
- rtx available_label, space, func;
+ rtx available_label, ask, space, func;
available_label = NULL_RTX;
@@ -1355,10 +1355,19 @@ allocate_dynamic_stack_space (rtx size,
}
#endif
+ /* The __morestack_allocate_stack_space function will allocate
+ memory using malloc. We don't know that the alignment of the
+ memory returned by malloc will meet REQUIRED_ALIGN. Increase
+ SIZE to make sure we allocate enough space. */
+ ask = expand_binop (Pmode, add_optab, size,
+ GEN_INT (required_align / BITS_PER_UNIT - 1),
+ NULL_RTX, 1, OPTAB_LIB_WIDEN);
+ must_align = true;
+
func = init_one_libfunc ("__morestack_allocate_stack_space");
space = emit_library_call_value (func, target, LCT_NORMAL, Pmode,
- 1, size, Pmode);
+ 1, ask, Pmode);
if (available_label == NULL_RTX)
return space;
===================================================================
@@ -0,0 +1,69 @@
+/* This test needs to use setrlimit to set the stack size, so it can
+ only run on Unix. */
+/* { dg-do run { target *-*-linux* *-*-solaris* *-*-darwin* } } */
+/* { dg-require-effective-target avx } */
+/* { dg-require-effective-target split_stack } */
+/* { dg-options "-fsplit-stack -O2 -mavx" } */
+
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/resource.h>
+
+/* Use a noinline function to ensure that the buffer is not removed
+ from the stack. */
+static void use_buffer (char *buf, size_t) __attribute__ ((noinline));
+static void
+use_buffer (char *buf, size_t c)
+{
+ size_t i;
+
+ for (i = 0; i < c; ++i)
+ buf[i] = (char) i;
+}
+
+/* Each recursive call uses 10 * i bytes. We call it 1000 times,
+ using a total of 5,000,000 bytes. If -fsplit-stack is not working,
+ that will overflow our stack limit. */
+
+static void
+down1 (int i)
+{
+ char buf[10 * i];
+
+ if (i > 0)
+ {
+ use_buffer (buf, 10 * i);
+ down1 (i - 1);
+ }
+}
+
+/* Same thing, using alloca. */
+
+static void
+down2 (int i)
+{
+ char *buf = alloca (10 * i);
+
+ if (i > 0)
+ {
+ use_buffer (buf, 10 * i);
+ down2 (i - 1);
+ }
+}
+
+int
+main (void)
+{
+ struct rlimit r;
+
+ /* We set a stack limit because we are usually invoked via make, and
+ make sets the stack limit to be as large as possible. */
+ r.rlim_cur = 8192 * 1024;
+ r.rlim_max = 8192 * 1024;
+ if (setrlimit (RLIMIT_STACK, &r) != 0)
+ abort ();
+ down1 (1000);
+ down2 (1000);
+ return 0;
+}