x86/fpu/math-emu, selftests: Add tests for FCMOV and FCOMI insns

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1442494933-13798-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile
index 29089b2..c4c9b90 100644 (file)
--- a/tools/testing/selftests/x86/Makefile
+++ b/tools/testing/selftests/x86/Makefile
@@ -5,7 +5,8 @@ include ../lib.mk
 .PHONY: all all_32 all_64 warn_32bit_failure clean
 
 TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs ldt_gdt syscall_nt
-TARGETS_C_32BIT_ONLY := entry_from_vm86 syscall_arg_fault sigreturn
+TARGETS_C_32BIT_ONLY := entry_from_vm86 syscall_arg_fault sigreturn \
+                       test_FCMOV test_FCOMI
 
 TARGETS_C_32BIT_ALL := $(TARGETS_C_BOTHBITS) $(TARGETS_C_32BIT_ONLY)
 BINARIES_32 := $(TARGETS_C_32BIT_ALL:%=%_32)
@@ -35,7 +36,7 @@ clean:
        $(RM) $(BINARIES_32) $(BINARIES_64)
 
 $(TARGETS_C_32BIT_ALL:%=%_32): %_32: %.c
-       $(CC) -m32 -o $@ $(CFLAGS) $(EXTRA_CFLAGS) $^ -lrt -ldl
+       $(CC) -m32 -o $@ $(CFLAGS) $(EXTRA_CFLAGS) $^ -lrt -ldl -lm
 
 $(TARGETS_C_BOTHBITS:%=%_64): %_64: %.c
        $(CC) -m64 -o $@ $(CFLAGS) $(EXTRA_CFLAGS) $^ -lrt -ldl

diff --git a/tools/testing/selftests/x86/test_FCMOV.c b/tools/testing/selftests/x86/test_FCMOV.c
new file mode 100644 (file)
index 0000000..4adcca0
--- /dev/null
+++ b/tools/testing/selftests/x86/test_FCMOV.c
@@ -0,0 +1,93 @@
+#undef _GNU_SOURCE
+#define _GNU_SOURCE 1
+#undef __USE_GNU
+#define __USE_GNU 1
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/select.h>
+#include <sys/time.h>
+#include <sys/wait.h>
+
+#define TEST(insn) \
+long double __attribute__((noinline)) insn(long flags) \
+{                                              \
+       long double out;                        \
+       asm ("\n"                               \
+       "       push    %1""\n"                 \
+       "       popf""\n"                       \
+       "       fldpi""\n"                      \
+       "       fld1""\n"                       \
+       "       " #insn " %%st(1), %%st" "\n"   \
+       "       ffree   %%st(1)" "\n"           \
+       : "=t" (out)                            \
+       : "r" (flags)                           \
+       );                                      \
+       return out;                             \
+}
+
+TEST(fcmovb)
+TEST(fcmove)
+TEST(fcmovbe)
+TEST(fcmovu)
+TEST(fcmovnb)
+TEST(fcmovne)
+TEST(fcmovnbe)
+TEST(fcmovnu)
+
+enum {
+       CF = 1 << 0,
+       PF = 1 << 2,
+       ZF = 1 << 6,
+};
+
+void sighandler(int sig)
+{
+       printf("[FAIL]\tGot signal %d, exiting\n", sig);
+       exit(1);
+}
+
+int main(int argc, char **argv, char **envp)
+{
+       int err = 0;
+
+       /* SIGILL triggers on 32-bit kernels w/o fcomi emulation
+        * when run with "no387 nofxsr". Other signals are caught
+        * just in case.
+        */
+       signal(SIGILL, sighandler);
+       signal(SIGFPE, sighandler);
+       signal(SIGSEGV, sighandler);
+
+       printf("[RUN]\tTesting fcmovCC instructions\n");
+       /* If fcmovCC() returns 1.0, the move wasn't done */
+       err |= !(fcmovb(0)   == 1.0); err |= !(fcmovnb(0)  != 1.0);
+       err |= !(fcmove(0)   == 1.0); err |= !(fcmovne(0)  != 1.0);
+       err |= !(fcmovbe(0)  == 1.0); err |= !(fcmovnbe(0) != 1.0);
+       err |= !(fcmovu(0)   == 1.0); err |= !(fcmovnu(0)  != 1.0);
+
+       err |= !(fcmovb(CF)  != 1.0); err |= !(fcmovnb(CF)  == 1.0);
+       err |= !(fcmove(CF)  == 1.0); err |= !(fcmovne(CF)  != 1.0);
+       err |= !(fcmovbe(CF) != 1.0); err |= !(fcmovnbe(CF) == 1.0);
+       err |= !(fcmovu(CF)  == 1.0); err |= !(fcmovnu(CF)  != 1.0);
+
+       err |= !(fcmovb(ZF)  == 1.0); err |= !(fcmovnb(ZF)  != 1.0);
+       err |= !(fcmove(ZF)  != 1.0); err |= !(fcmovne(ZF)  == 1.0);
+       err |= !(fcmovbe(ZF) != 1.0); err |= !(fcmovnbe(ZF) == 1.0);
+       err |= !(fcmovu(ZF)  == 1.0); err |= !(fcmovnu(ZF)  != 1.0);
+
+       err |= !(fcmovb(PF)  == 1.0); err |= !(fcmovnb(PF)  != 1.0);
+       err |= !(fcmove(PF)  == 1.0); err |= !(fcmovne(PF)  != 1.0);
+       err |= !(fcmovbe(PF) == 1.0); err |= !(fcmovnbe(PF) != 1.0);
+       err |= !(fcmovu(PF)  != 1.0); err |= !(fcmovnu(PF)  == 1.0);
+
+        if (!err)
+                printf("[OK]\tfcmovCC\n");
+       else
+               printf("[FAIL]\tfcmovCC errors: %d\n", err);
+
+       return err;
+}

diff --git a/tools/testing/selftests/x86/test_FCOMI.c b/tools/testing/selftests/x86/test_FCOMI.c
new file mode 100644 (file)
index 0000000..db4933e
--- /dev/null
+++ b/tools/testing/selftests/x86/test_FCOMI.c
@@ -0,0 +1,331 @@
+#undef _GNU_SOURCE
+#define _GNU_SOURCE 1
+#undef __USE_GNU
+#define __USE_GNU 1
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/select.h>
+#include <sys/time.h>
+#include <sys/wait.h>
+#include <fenv.h>
+
+enum {
+       CF = 1 << 0,
+       PF = 1 << 2,
+       ZF = 1 << 6,
+       ARITH = CF | PF | ZF,
+};
+
+long res_fcomi_pi_1;
+long res_fcomi_1_pi;
+long res_fcomi_1_1;
+long res_fcomi_nan_1;
+/* sNaN is s|111 1111 1|1xx xxxx xxxx xxxx xxxx xxxx */
+/* qNaN is s|111 1111 1|0xx xxxx xxxx xxxx xxxx xxxx (some x must be nonzero) */
+int snan = 0x7fc11111;
+int qnan = 0x7f811111;
+unsigned short snan1[5];
+/* sNaN80 is s|111 1111 1111 1111 |10xx xx...xx (some x must be nonzero) */
+unsigned short snan80[5] = { 0x1111, 0x1111, 0x1111, 0x8111, 0x7fff };
+
+int test(long flags)
+{
+       feclearexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
+
+       asm ("\n"
+
+       "       push    %0""\n"
+       "       popf""\n"
+       "       fld1""\n"
+       "       fldpi""\n"
+       "       fcomi   %%st(1), %%st" "\n"
+       "       ffree   %%st(0)" "\n"
+       "       ffree   %%st(1)" "\n"
+       "       pushf""\n"
+       "       pop     res_fcomi_1_pi""\n"
+
+       "       push    %0""\n"
+       "       popf""\n"
+       "       fldpi""\n"
+       "       fld1""\n"
+       "       fcomi   %%st(1), %%st" "\n"
+       "       ffree   %%st(0)" "\n"
+       "       ffree   %%st(1)" "\n"
+       "       pushf""\n"
+       "       pop     res_fcomi_pi_1""\n"
+
+       "       push    %0""\n"
+       "       popf""\n"
+       "       fld1""\n"
+       "       fld1""\n"
+       "       fcomi   %%st(1), %%st" "\n"
+       "       ffree   %%st(0)" "\n"
+       "       ffree   %%st(1)" "\n"
+       "       pushf""\n"
+       "       pop     res_fcomi_1_1""\n"
+       :
+       : "r" (flags)
+       );
+       if ((res_fcomi_1_pi & ARITH) != (0)) {
+               printf("[BAD]\tfcomi_1_pi with flags:%lx\n", flags);
+               return 1;
+       }
+       if ((res_fcomi_pi_1 & ARITH) != (CF)) {
+               printf("[BAD]\tfcomi_pi_1 with flags:%lx->%lx\n", flags, res_fcomi_pi_1 & ARITH);
+               return 1;
+       }
+       if ((res_fcomi_1_1 & ARITH) != (ZF)) {
+               printf("[BAD]\tfcomi_1_1 with flags:%lx\n", flags);
+               return 1;
+       }
+       if (fetestexcept(FE_INVALID) != 0) {
+               printf("[BAD]\tFE_INVALID is set in %s\n", __func__);
+               return 1;
+       }
+       return 0;
+}
+
+int test_qnan(long flags)
+{
+       feclearexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
+
+       asm ("\n"
+       "       push    %0""\n"
+       "       popf""\n"
+       "       flds    qnan""\n"
+       "       fld1""\n"
+       "       fnclex""\n"             // fld of a qnan raised FE_INVALID, clear it
+       "       fcomi   %%st(1), %%st" "\n"
+       "       ffree   %%st(0)" "\n"
+       "       ffree   %%st(1)" "\n"
+       "       pushf""\n"
+       "       pop     res_fcomi_nan_1""\n"
+       :
+       : "r" (flags)
+       );
+       if ((res_fcomi_nan_1 & ARITH) != (ZF|CF|PF)) {
+               printf("[BAD]\tfcomi_qnan_1 with flags:%lx\n", flags);
+               return 1;
+       }
+       if (fetestexcept(FE_INVALID) != FE_INVALID) {
+               printf("[BAD]\tFE_INVALID is not set in %s\n", __func__);
+               return 1;
+       }
+       return 0;
+}
+
+int testu_qnan(long flags)
+{
+       feclearexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
+
+       asm ("\n"
+       "       push    %0""\n"
+       "       popf""\n"
+       "       flds    qnan""\n"
+       "       fld1""\n"
+       "       fnclex""\n"             // fld of a qnan raised FE_INVALID, clear it
+       "       fucomi  %%st(1), %%st" "\n"
+       "       ffree   %%st(0)" "\n"
+       "       ffree   %%st(1)" "\n"
+       "       pushf""\n"
+       "       pop     res_fcomi_nan_1""\n"
+       :
+       : "r" (flags)
+       );
+       if ((res_fcomi_nan_1 & ARITH) != (ZF|CF|PF)) {
+               printf("[BAD]\tfcomi_qnan_1 with flags:%lx\n", flags);
+               return 1;
+       }
+       if (fetestexcept(FE_INVALID) != 0) {
+               printf("[BAD]\tFE_INVALID is set in %s\n", __func__);
+               return 1;
+       }
+       return 0;
+}
+
+int testu_snan(long flags)
+{
+       feclearexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
+
+       asm ("\n"
+       "       push    %0""\n"
+       "       popf""\n"
+//     "       flds    snan""\n"       // WRONG, this will convert 32-bit fp snan to a *qnan* in 80-bit fp register!
+//     "       fstpt   snan1""\n"      // if uncommented, it prints "snan1:7fff c111 1100 0000 0000" - c111, not 8111!
+//     "       fnclex""\n"             // flds of a snan raised FE_INVALID, clear it
+       "       fldt    snan80""\n"     // fldt never raise FE_INVALID
+       "       fld1""\n"
+       "       fucomi  %%st(1), %%st" "\n"
+       "       ffree   %%st(0)" "\n"
+       "       ffree   %%st(1)" "\n"
+       "       pushf""\n"
+       "       pop     res_fcomi_nan_1""\n"
+       :
+       : "r" (flags)
+       );
+       if ((res_fcomi_nan_1 & ARITH) != (ZF|CF|PF)) {
+               printf("[BAD]\tfcomi_qnan_1 with flags:%lx\n", flags);
+               return 1;
+       }
+//     printf("snan:%x snan1:%04x %04x %04x %04x %04x\n", snan, snan1[4], snan1[3], snan1[2], snan1[1], snan1[0]);
+       if (fetestexcept(FE_INVALID) != FE_INVALID) {
+               printf("[BAD]\tFE_INVALID is not set in %s\n", __func__);
+               return 1;
+       }
+       return 0;
+}
+
+int testp(long flags)
+{
+       feclearexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
+
+       asm ("\n"
+
+       "       push    %0""\n"
+       "       popf""\n"
+       "       fld1""\n"
+       "       fldpi""\n"
+       "       fcomip  %%st(1), %%st" "\n"
+       "       ffree   %%st(0)" "\n"
+       "       pushf""\n"
+       "       pop     res_fcomi_1_pi""\n"
+
+       "       push    %0""\n"
+       "       popf""\n"
+       "       fldpi""\n"
+       "       fld1""\n"
+       "       fcomip  %%st(1), %%st" "\n"
+       "       ffree   %%st(0)" "\n"
+       "       pushf""\n"
+       "       pop     res_fcomi_pi_1""\n"
+
+       "       push    %0""\n"
+       "       popf""\n"
+       "       fld1""\n"
+       "       fld1""\n"
+       "       fcomip  %%st(1), %%st" "\n"
+       "       ffree   %%st(0)" "\n"
+       "       pushf""\n"
+       "       pop     res_fcomi_1_1""\n"
+       :
+       : "r" (flags)
+       );
+       if ((res_fcomi_1_pi & ARITH) != (0)) {
+               printf("[BAD]\tfcomi_1_pi with flags:%lx\n", flags);
+               return 1;
+       }
+       if ((res_fcomi_pi_1 & ARITH) != (CF)) {
+               printf("[BAD]\tfcomi_pi_1 with flags:%lx->%lx\n", flags, res_fcomi_pi_1 & ARITH);
+               return 1;
+       }
+       if ((res_fcomi_1_1 & ARITH) != (ZF)) {
+               printf("[BAD]\tfcomi_1_1 with flags:%lx\n", flags);
+               return 1;
+       }
+       if (fetestexcept(FE_INVALID) != 0) {
+               printf("[BAD]\tFE_INVALID is set in %s\n", __func__);
+               return 1;
+       }
+       return 0;
+}
+
+int testp_qnan(long flags)
+{
+       feclearexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
+
+       asm ("\n"
+       "       push    %0""\n"
+       "       popf""\n"
+       "       flds    qnan""\n"
+       "       fld1""\n"
+       "       fnclex""\n"             // fld of a qnan raised FE_INVALID, clear it
+       "       fcomip  %%st(1), %%st" "\n"
+       "       ffree   %%st(0)" "\n"
+       "       pushf""\n"
+       "       pop     res_fcomi_nan_1""\n"
+       :
+       : "r" (flags)
+       );
+       if ((res_fcomi_nan_1 & ARITH) != (ZF|CF|PF)) {
+               printf("[BAD]\tfcomi_qnan_1 with flags:%lx\n", flags);
+               return 1;
+       }
+       if (fetestexcept(FE_INVALID) != FE_INVALID) {
+               printf("[BAD]\tFE_INVALID is not set in %s\n", __func__);
+               return 1;
+       }
+       return 0;
+}
+
+int testup_qnan(long flags)
+{
+       feclearexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
+
+       asm ("\n"
+       "       push    %0""\n"
+       "       popf""\n"
+       "       flds    qnan""\n"
+       "       fld1""\n"
+       "       fnclex""\n"             // fld of a qnan raised FE_INVALID, clear it
+       "       fucomip %%st(1), %%st" "\n"
+       "       ffree   %%st(0)" "\n"
+       "       pushf""\n"
+       "       pop     res_fcomi_nan_1""\n"
+       :
+       : "r" (flags)
+       );
+       if ((res_fcomi_nan_1 & ARITH) != (ZF|CF|PF)) {
+               printf("[BAD]\tfcomi_qnan_1 with flags:%lx\n", flags);
+               return 1;
+       }
+       if (fetestexcept(FE_INVALID) != 0) {
+               printf("[BAD]\tFE_INVALID is set in %s\n", __func__);
+               return 1;
+       }
+       return 0;
+}
+
+void sighandler(int sig)
+{
+       printf("[FAIL]\tGot signal %d, exiting\n", sig);
+       exit(1);
+}
+
+int main(int argc, char **argv, char **envp)
+{
+       int err = 0;
+
+       /* SIGILL triggers on 32-bit kernels w/o fcomi emulation
+        * when run with "no387 nofxsr". Other signals are caught
+        * just in case.
+        */
+       signal(SIGILL, sighandler);
+       signal(SIGFPE, sighandler);
+       signal(SIGSEGV, sighandler);
+
+       printf("[RUN]\tTesting f[u]comi[p] instructions\n");
+       err |= test(0);
+       err |= test_qnan(0);
+       err |= testu_qnan(0);
+       err |= testu_snan(0);
+       err |= test(CF|ZF|PF);
+       err |= test_qnan(CF|ZF|PF);
+       err |= testu_qnan(CF|ZF|PF);
+       err |= testu_snan(CF|ZF|PF);
+       err |= testp(0);
+       err |= testp_qnan(0);
+       err |= testup_qnan(0);
+       err |= testp(CF|ZF|PF);
+       err |= testp_qnan(CF|ZF|PF);
+       err |= testup_qnan(CF|ZF|PF);
+       if (!err)
+               printf("[OK]\tf[u]comi[p]\n");
+       else
+               printf("[FAIL]\tf[u]comi[p] errors: %d\n", err);
+
+       return err;
+}