root/tools/testing/selftests/kvm/x86/fastops_test.c
// SPDX-License-Identifier: GPL-2.0-only
#include "test_util.h"
#include "kvm_util.h"
#include "processor.h"

/*
 * Execute a fastop() instruction, with or without forced emulation.  BT bit 0
 * to set RFLAGS.CF based on whether or not the input is even or odd, so that
 * instructions like ADC and SBB are deterministic.
 */
#define fastop(__insn)                                                                  \
        "bt $0, %[bt_val]\n\t"                                                          \
        __insn "\n\t"                                                                   \
        "pushfq\n\t"                                                                    \
        "pop %[flags]\n\t"

#define flags_constraint(flags_val) [flags]"=r"(flags_val)
#define bt_constraint(__bt_val) [bt_val]"rm"((uint32_t)__bt_val)

#define guest_execute_fastop_1(FEP, insn, __val, __flags)                               \
({                                                                                      \
        __asm__ __volatile__(fastop(FEP insn " %[val]")                                 \
                             : [val]"+r"(__val), flags_constraint(__flags)              \
                             : bt_constraint(__val)                                     \
                             : "cc", "memory");                                         \
})

#define guest_test_fastop_1(insn, type_t, __val)                                        \
({                                                                                      \
        type_t val = __val, ex_val = __val, input = __val;                              \
        uint64_t flags, ex_flags;                                                       \
                                                                                        \
        guest_execute_fastop_1("", insn, ex_val, ex_flags);                             \
        guest_execute_fastop_1(KVM_FEP, insn, val, flags);                              \
                                                                                        \
        __GUEST_ASSERT(val == ex_val,                                                   \
                       "Wanted 0x%lx for '%s 0x%lx', got 0x%lx",                        \
                       (uint64_t)ex_val, insn, (uint64_t)input, (uint64_t)val);         \
        __GUEST_ASSERT(flags == ex_flags,                                               \
                        "Wanted flags 0x%lx for '%s 0x%lx', got 0x%lx",                 \
                        ex_flags, insn, (uint64_t)input, flags);                        \
})

#define guest_execute_fastop_2(FEP, insn, __input, __output, __flags)                   \
({                                                                                      \
        __asm__ __volatile__(fastop(FEP insn " %[input], %[output]")                    \
                             : [output]"+r"(__output), flags_constraint(__flags)        \
                             : [input]"r"(__input), bt_constraint(__output)             \
                             : "cc", "memory");                                         \
})

#define guest_test_fastop_2(insn, type_t, __val1, __val2)                               \
({                                                                                      \
        type_t input = __val1, input2 = __val2, output = __val2, ex_output = __val2;    \
        uint64_t flags, ex_flags;                                                       \
                                                                                        \
        guest_execute_fastop_2("", insn, input, ex_output, ex_flags);                   \
        guest_execute_fastop_2(KVM_FEP, insn, input, output, flags);                    \
                                                                                        \
        __GUEST_ASSERT(output == ex_output,                                             \
                       "Wanted 0x%lx for '%s 0x%lx 0x%lx', got 0x%lx",                  \
                       (uint64_t)ex_output, insn, (uint64_t)input,                      \
                       (uint64_t)input2, (uint64_t)output);                             \
        __GUEST_ASSERT(flags == ex_flags,                                               \
                        "Wanted flags 0x%lx for '%s 0x%lx, 0x%lx', got 0x%lx",          \
                        ex_flags, insn, (uint64_t)input, (uint64_t)input2, flags);      \
})

#define guest_execute_fastop_cl(FEP, insn, __shift, __output, __flags)                  \
({                                                                                      \
        __asm__ __volatile__(fastop(FEP insn " %%cl, %[output]")                        \
                             : [output]"+r"(__output), flags_constraint(__flags)        \
                             : "c"(__shift), bt_constraint(__output)                    \
                             : "cc", "memory");                                         \
})

#define guest_test_fastop_cl(insn, type_t, __val1, __val2)                              \
({                                                                                      \
        type_t output = __val2, ex_output = __val2, input = __val2;                     \
        uint8_t shift = __val1;                                                         \
        uint64_t flags, ex_flags;                                                       \
                                                                                        \
        guest_execute_fastop_cl("", insn, shift, ex_output, ex_flags);                  \
        guest_execute_fastop_cl(KVM_FEP, insn, shift, output, flags);                   \
                                                                                        \
        __GUEST_ASSERT(output == ex_output,                                             \
                       "Wanted 0x%lx for '%s 0x%x, 0x%lx', got 0x%lx",                  \
                       (uint64_t)ex_output, insn, shift, (uint64_t)input,               \
                       (uint64_t)output);                                               \
        __GUEST_ASSERT(flags == ex_flags,                                               \
                        "Wanted flags 0x%lx for '%s 0x%x, 0x%lx', got 0x%lx",           \
                        ex_flags, insn, shift, (uint64_t)input, flags);                 \
})

#define guest_execute_fastop_div(__KVM_ASM_SAFE, insn, __a, __d, __rm, __flags)         \
({                                                                                      \
        uint64_t ign_error_code;                                                        \
        uint8_t vector;                                                                 \
                                                                                        \
        __asm__ __volatile__(fastop(__KVM_ASM_SAFE(insn " %[denom]"))                   \
                             : "+a"(__a), "+d"(__d), flags_constraint(__flags),         \
                               KVM_ASM_SAFE_OUTPUTS(vector, ign_error_code)             \
                             : [denom]"rm"(__rm), bt_constraint(__rm)                   \
                             : "cc", "memory", KVM_ASM_SAFE_CLOBBERS);                  \
        vector;                                                                         \
})

#define guest_test_fastop_div(insn, type_t, __val1, __val2)                             \
({                                                                                      \
        type_t _a = __val1, _d = __val1, rm = __val2;                                   \
        type_t a = _a, d = _d, ex_a = _a, ex_d = _d;                                    \
        uint64_t flags, ex_flags;                                                       \
        uint8_t v, ex_v;                                                                \
                                                                                        \
        ex_v = guest_execute_fastop_div(KVM_ASM_SAFE, insn, ex_a, ex_d, rm, ex_flags);  \
        v = guest_execute_fastop_div(KVM_ASM_SAFE_FEP, insn, a, d, rm, flags);          \
                                                                                        \
        GUEST_ASSERT_EQ(v, ex_v);                                                       \
        __GUEST_ASSERT(v == ex_v,                                                       \
                       "Wanted vector 0x%x for '%s 0x%lx:0x%lx/0x%lx', got 0x%x",       \
                       ex_v, insn, (uint64_t)_a, (uint64_t)_d, (uint64_t)rm, v);        \
        __GUEST_ASSERT(a == ex_a && d == ex_d,                                          \
                       "Wanted 0x%lx:0x%lx for '%s 0x%lx:0x%lx/0x%lx', got 0x%lx:0x%lx",\
                       (uint64_t)ex_a, (uint64_t)ex_d, insn, (uint64_t)_a,              \
                       (uint64_t)_d, (uint64_t)rm, (uint64_t)a, (uint64_t)d);           \
        __GUEST_ASSERT(v || ex_v || (flags == ex_flags),                                \
                        "Wanted flags 0x%lx for '%s  0x%lx:0x%lx/0x%lx', got 0x%lx",    \
                        ex_flags, insn, (uint64_t)_a, (uint64_t)_d, (uint64_t)rm, flags);\
})

static const uint64_t vals[] = {
        0,
        1,
        2,
        4,
        7,
        0x5555555555555555,
        0xaaaaaaaaaaaaaaaa,
        0xfefefefefefefefe,
        0xffffffffffffffff,
};

#define guest_test_fastops(type_t, suffix)                                              \
do {                                                                                    \
        int i, j;                                                                       \
                                                                                        \
        for (i = 0; i < ARRAY_SIZE(vals); i++) {                                        \
                guest_test_fastop_1("dec" suffix, type_t, vals[i]);                     \
                guest_test_fastop_1("inc" suffix, type_t, vals[i]);                     \
                guest_test_fastop_1("neg" suffix, type_t, vals[i]);                     \
                guest_test_fastop_1("not" suffix, type_t, vals[i]);                     \
                                                                                        \
                for (j = 0; j < ARRAY_SIZE(vals); j++) {                                \
                        guest_test_fastop_2("add" suffix, type_t, vals[i], vals[j]);    \
                        guest_test_fastop_2("adc" suffix, type_t, vals[i], vals[j]);    \
                        guest_test_fastop_2("and" suffix, type_t, vals[i], vals[j]);    \
if (sizeof(type_t) != 1) {                                                      \
                        guest_test_fastop_2("bsf" suffix, type_t, vals[i], vals[j]);    \
                        guest_test_fastop_2("bsr" suffix, type_t, vals[i], vals[j]);    \
                        guest_test_fastop_2("bt" suffix, type_t, vals[i], vals[j]);     \
                        guest_test_fastop_2("btc" suffix, type_t, vals[i], vals[j]);    \
                        guest_test_fastop_2("btr" suffix, type_t, vals[i], vals[j]);    \
                        guest_test_fastop_2("bts" suffix, type_t, vals[i], vals[j]);    \
                        guest_test_fastop_2("imul" suffix, type_t, vals[i], vals[j]);   \
}                                                                                       \
                        guest_test_fastop_2("cmp" suffix, type_t, vals[i], vals[j]);    \
                        guest_test_fastop_2("or" suffix, type_t, vals[i], vals[j]);     \
                        guest_test_fastop_2("sbb" suffix, type_t, vals[i], vals[j]);    \
                        guest_test_fastop_2("sub" suffix, type_t, vals[i], vals[j]);    \
                        guest_test_fastop_2("test" suffix, type_t, vals[i], vals[j]);   \
                        guest_test_fastop_2("xor" suffix, type_t, vals[i], vals[j]);    \
                                                                                        \
                        guest_test_fastop_cl("rol" suffix, type_t, vals[i], vals[j]);   \
                        guest_test_fastop_cl("ror" suffix, type_t, vals[i], vals[j]);   \
                        guest_test_fastop_cl("rcl" suffix, type_t, vals[i], vals[j]);   \
                        guest_test_fastop_cl("rcr" suffix, type_t, vals[i], vals[j]);   \
                        guest_test_fastop_cl("sar" suffix, type_t, vals[i], vals[j]);   \
                        guest_test_fastop_cl("shl" suffix, type_t, vals[i], vals[j]);   \
                        guest_test_fastop_cl("shr" suffix, type_t, vals[i], vals[j]);   \
                                                                                        \
                        guest_test_fastop_div("div" suffix, type_t, vals[i], vals[j]);  \
                }                                                                       \
        }                                                                               \
} while (0)

static void guest_code(void)
{
        guest_test_fastops(uint8_t, "b");
        guest_test_fastops(uint16_t, "w");
        guest_test_fastops(uint32_t, "l");
        guest_test_fastops(uint64_t, "q");

        GUEST_DONE();
}

int main(int argc, char *argv[])
{
        struct kvm_vcpu *vcpu;
        struct kvm_vm *vm;

        TEST_REQUIRE(is_forced_emulation_enabled);

        vm = vm_create_with_one_vcpu(&vcpu, guest_code);

        vcpu_run(vcpu);
        TEST_ASSERT_EQ(get_ucall(vcpu, NULL), UCALL_DONE);

        kvm_vm_free(vm);
}