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 * Copyright (c) 2015-2017, Intel Corporation
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 *    may be used to endorse or promote products derived from this software
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#include "config.h"
#include "gtest/gtest.h"

#include "fdr/fdr_loadval.h"
#include "util/bytecode_ptr.h"

using namespace std;
using namespace testing;
using namespace ue2;

// Normal (unaligned) load.
template <typename T> T lv(const u8 *ptr, const u8 *lo, const u8 *hi);

// Cautious everywhere load.
template <typename T> T lv_ce(const u8 *ptr, const u8 *lo, const u8 *hi);

#define BUILD_LOADVALS(vtype)                                                  \
    template <> vtype lv<vtype>(const u8 *ptr, const u8 *lo, const u8 *hi) {   \
        return lv_##vtype(ptr, lo, hi);                                        \
    }                                                                          \
    template <>                                                                \
    vtype lv_ce<vtype>(const u8 *ptr, const u8 *lo, const u8 *hi) {            \
        return lv_##vtype##_ce(ptr, lo, hi);                                   \
    }

BUILD_LOADVALS(u16)
BUILD_LOADVALS(u64a)

template <typename T> class FDR_Loadval : public testing::Test {
    // empty
};

typedef ::testing::Types<u16, u64a> LoadvalTypes;

TYPED_TEST_CASE(FDR_Loadval, LoadvalTypes);

static void fillWithBytes(u8 *ptr, size_t len) {
    for (size_t i = 0; i < len; i++) {
        ptr[i] = (u8)(i % 254 + 1);
    }
}

TYPED_TEST(FDR_Loadval, Normal) {
    // We should be able to do a normal load at any alignment.
    const size_t len = sizeof(TypeParam);
    auto mem_p = make_bytecode_ptr<u8>(len + 15, 16);
    u8 * mem = mem_p.get();
    ASSERT_TRUE(ISALIGNED_16(mem));
    fillWithBytes(mem, len + 15);

    // Test all alignments.
    for (size_t i = 0; i < 16; i++) {
        const u8 *src = mem + i;
        TypeParam val = lv<TypeParam>(src, src, src + len);
        // Should be identical to 'src' in byte order.
        ASSERT_EQ(0, memcmp(&val, src, len));
    }
}

TYPED_TEST(FDR_Loadval, CautiousEverywhere) {
    // For a cautious backwards load, we will get zeroes for all bytes before
    // the 'lo' ptr or after the 'hi' ptr.
    const size_t len = sizeof(TypeParam);

    auto mem_p = make_bytecode_ptr<u8>(len + 1, 16);
    u8 *mem = mem_p.get() + 1; // force unaligned
    fillWithBytes(mem, len);

    for (size_t i = 0; i <= len; i++) {
        for (size_t j = 0; j <= len; j++) {
            const u8 *ptr = mem;
            const u8 *lo = ptr + i;
            const u8 *hi = ptr + j;
            union {
                TypeParam val;
                u8 bytes[sizeof(TypeParam)];
            } x;

            x.val = lv_ce<TypeParam>(ptr, lo, hi);

            // Bytes outside [lo,hi) will be zero.
            for (size_t k = 0; k < len; k++) {
                ASSERT_EQ((k >= i && k < j) ? mem[k] : 0, x.bytes[k]);
            }
        }
    }
}