S390: Skip Simd tests if VEF1 is not available on the host machine

Change-Id: I57c6989ff0ca872b66567c701c2b9bf8ee6e83d9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2983069
Commit-Queue: Milad Fa <mfarazma@redhat.com>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75398}

tools/testrunner/base_runner.py

@@ -663,6 +663,12 @@ class BaseTestRunner(object):
        self.build_config.arch == 'mipsel':
        no_simd_hardware = not simd_mips
 
+    # S390 hosts without VEF1 do not support Simd.
+    if self.build_config.arch == 's390x' and \
+       not self.build_config.simulator_run and \
+       not utils.IsS390SimdSupported():
+       no_simd_hardware = True
+
     # Ppc64 processors earlier than POWER9 do not support Simd instructions
     if self.build_config.arch == 'ppc64' and \
        not self.build_config.simulator_run and \

tools/testrunner/local/utils.py

@@ -97,6 +97,18 @@ def GuessOS():
     return None
 
 
+# Check if Vector Enhancement Facility 1 is available on the
+# host S390 machine. This facility is required for supporting Simd on V8.
+def IsS390SimdSupported():
+  import subprocess
+  cpuinfo = subprocess.check_output("cat /proc/cpuinfo", shell=True)
+  cpuinfo_list = cpuinfo.strip().decode("utf-8").splitlines()
+  facilities = "".join(x for x in cpuinfo_list if x.startswith("facilities"))
+  facilities_list = facilities.split(" ")
+  # Having bit 135 set indicates VEF1 is available.
+  return "135" in facilities_list
+
+
 # Returns power processor version, taking compatibility mode into account.
 # (Power9 running in Power8 compatibility mode returns 8)
 # Only useful if arch is ppc64