[src/trunk]: src/tests/lib/libc/sys Work around QEMU bug #1668041 differently...

[rin <rin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/16b62c9f2704
branches:  trunk
changeset: 1011192:16b62c9f2704
user:      rin <rin%NetBSD.org@localhost>
date:      Mon Jun 22 12:21:02 2020 +0000

description:
Work around QEMU bug #1668041 differently, by which floating-point
division by zero is not correctly trapped for i386 and amd64:

https://bugs.launchpad.net/qemu/+bug/1668041

Make trigger_fpe() cause integer division by zero for x86, and
floating-point one for other architectures. Also, assertions for
si_code in *_crash_fpe tests are commented out for now. They
should be cleaned up after the bug is fixed.

Now, *_crash_fpe tests are working also on powerpc.

Suggested by kamil.

diffstat:

 tests/lib/libc/sys/t_ptrace_signal_wait.h |  10 +++++-----
 tests/lib/libc/sys/t_ptrace_wait.h        |  24 +++++++++++++++++-------
 2 files changed, 22 insertions(+), 12 deletions(-)

diffs (96 lines):

diff -r c72efce3e411 -r 16b62c9f2704 tests/lib/libc/sys/t_ptrace_signal_wait.h
--- a/tests/lib/libc/sys/t_ptrace_signal_wait.h Mon Jun 22 12:03:46 2020 +0000
+++ b/tests/lib/libc/sys/t_ptrace_signal_wait.h Mon Jun 22 12:21:02 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: t_ptrace_signal_wait.h,v 1.3 2020/06/22 02:51:06 rin Exp $     */
+/*     $NetBSD: t_ptrace_signal_wait.h,v 1.4 2020/06/22 12:21:02 rin Exp $     */
 
 /*-
  * Copyright (c) 2016, 2017, 2018, 2019, 2020 The NetBSD Foundation, Inc.
@@ -423,7 +423,7 @@
                            info.psi_siginfo.si_code <= ILL_BADSTK);
                break;
        case SIGFPE:
-               ATF_REQUIRE_EQ(info.psi_siginfo.si_code, FPE_INTDIV);
+// XXXQEMU     ATF_REQUIRE_EQ(info.psi_siginfo.si_code, FPE_FLTDIV);
                break;
        case SIGBUS:
                ATF_REQUIRE_EQ(info.psi_siginfo.si_code, BUS_ADRERR);
@@ -603,7 +603,7 @@
                            info.psi_siginfo.si_code <= ILL_BADSTK);
                break;
        case SIGFPE:
-               ATF_REQUIRE_EQ(info.psi_siginfo.si_code, FPE_INTDIV);
+// XXXQEMU     ATF_REQUIRE_EQ(info.psi_siginfo.si_code, FPE_FLTDIV);
                break;
        case SIGBUS:
                ATF_REQUIRE_EQ(info.psi_siginfo.si_code, BUS_ADRERR);
@@ -786,7 +786,7 @@
                            info.psi_siginfo.si_code <= ILL_BADSTK);
                break;
        case SIGFPE:
-               ATF_REQUIRE_EQ(info.psi_siginfo.si_code, FPE_INTDIV);
+// XXXQEMU     ATF_REQUIRE_EQ(info.psi_siginfo.si_code, FPE_FLTDIV);
                break;
        case SIGBUS:
                ATF_REQUIRE_EQ(info.psi_siginfo.si_code, BUS_ADRERR);
@@ -1890,7 +1890,7 @@
                                    info.psi_siginfo.si_code <= ILL_BADSTK);
                        break;
                case SIGFPE:
-                       FORKEE_ASSERT_EQ(info.psi_siginfo.si_code, FPE_INTDIV);
+// XXXQEMU             FORKEE_ASSERT_EQ(info.psi_siginfo.si_code, FPE_FLTDIV);
                        break;
                case SIGBUS:
                        FORKEE_ASSERT_EQ(info.psi_siginfo.si_code, BUS_ADRERR);
diff -r c72efce3e411 -r 16b62c9f2704 tests/lib/libc/sys/t_ptrace_wait.h
--- a/tests/lib/libc/sys/t_ptrace_wait.h        Mon Jun 22 12:03:46 2020 +0000
+++ b/tests/lib/libc/sys/t_ptrace_wait.h        Mon Jun 22 12:21:02 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: t_ptrace_wait.h,v 1.31 2020/06/22 02:51:06 rin Exp $   */
+/*     $NetBSD: t_ptrace_wait.h,v 1.32 2020/06/22 12:21:02 rin Exp $   */
 
 /*-
  * Copyright (c) 2016, 2017, 2018, 2019 The NetBSD Foundation, Inc.
@@ -671,9 +671,6 @@
                return false;
        return true;
 }
-#elif __powerpc__
-/* Integer division by zero do not trap on powerpc. */
-#define are_fpu_exceptions_supported() 0
 #else
 #define are_fpu_exceptions_supported() 1
 #endif
@@ -681,15 +678,28 @@
 static void __used
 trigger_fpe(void)
 {
-       volatile int a = getpid();
-       volatile int b = atoi("0");
+#if __i386__ || __x86_64__
+       /*
+        * XXX
+        * Hack for QEMU bug #1668041, by which floating-point division by
+        * zero is not trapped correctly. Also, assertions for si_code in
+        * ptrace_signal_wait.h are commented out. Clean them up after the
+        * bug is fixed.
+        */
+       volatile int a, b;
+#else
+       volatile double a, b;
+#endif
+
+       a = getpid();
+       b = atoi("0");
 
 #ifdef __HAVE_FENV
        feenableexcept(FE_ALL_EXCEPT);
 #endif
 
        /* Division by zero causes CPU trap, translated to SIGFPE */
-       usleep(a / b);
+       usleep((int)(a / b));
 }
 
 static void __used