Re: [PATCH] libgomp: Fix default value of GOMP_SPINCOUNT [PR 109062]

[Hongyu Wang <wwwhhhyyy333@gmail.com>]

> Seems for many ICVs the default values are done through
> gomp_default_icv_values, but that doesn't cover wait_policy.
> For other vars, the defaults are provided through just initializers of
> those vars on the var definitions, e.g.:
> char *gomp_affinity_format_var = "level %L thread %i affinity %A";
> So, I'd do the initialize_icvs change and change
> static int wait_policy;
> to
> static int wait_policy = -1;

Agreed, here is the updated patch, ok for trunk?

When OMP_WAIT_POLICY is not specified, current implementation will cause
icv flag GOMP_ICV_WAIT_POLICY unset, so global variable wait_policy
will remain its uninitialized value. Initialize it to -1 to make
GOMP_SPINCOUNT behavior consistent with its description.

libgomp/ChangeLog:

PR libgomp/109062
* env.c (wait_policy): Initialize to -1.
(initialize_icvs): Initialize icvs->wait_policy to -1.
* testsuite/libgomp.c-c++-common/pr109062.c: New test.
---
 libgomp/env.c                                     |  4 ++--
 libgomp/testsuite/libgomp.c-c++-common/pr109062.c | 14 ++++++++++++++
 2 files changed, 16 insertions(+), 2 deletions(-)
 create mode 100644 libgomp/testsuite/libgomp.c-c++-common/pr109062.c

diff --git a/libgomp/env.c b/libgomp/env.c
index c41c1f852cc..e7a035b593c 100644
--- a/libgomp/env.c
+++ b/libgomp/env.c
@@ -124,7 +124,7 @@ int goacc_default_dims[GOMP_DIM_MAX];

 #ifndef LIBGOMP_OFFLOADED_ONLY

-static int wait_policy;
+static int wait_policy = -1;
 static unsigned long stacksize = GOMP_DEFAULT_STACKSIZE;

 static void
@@ -1981,7 +1981,7 @@ initialize_icvs (struct gomp_initial_icvs *icvs)
   icvs->bind_var = gomp_default_icv_values.bind_var;
   icvs->nteams_var = gomp_default_icv_values.nteams_var;
   icvs->teams_thread_limit_var =
gomp_default_icv_values.teams_thread_limit_var;
-  icvs->wait_policy = 0;
+  icvs->wait_policy = -1;
 }

 /* Helper function for initialize_env to add a device specific ICV value
diff --git a/libgomp/testsuite/libgomp.c-c++-common/pr109062.c
b/libgomp/testsuite/libgomp.c-c++-common/pr109062.c
new file mode 100644
index 00000000000..5c7c287dafd
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c-c++-common/pr109062.c
@@ -0,0 +1,14 @@
+/* { dg-do run } */
+
+#include <omp.h>
+#include <stdlib.h>
+
+int
+main ()
+{
+  omp_display_env (1);
+
+  return 0;
+}
+
+/* { dg-output ".*\\\[host] GOMP_SPINCOUNT = '300000'.*" { target native } } */
-- 
2.31.1