libmwemu 0.24.1

x86 32/64bits and system internals emulator, for securely emulating malware and other stuff.
Documentation 
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//! Tests for PMULLW instruction.
//!
//! PMULLW - Packed Multiply Low (MMX)
//!
//! Performs SIMD signed multiply of 4 packed 16-bit word integers.
//! Stores the low 16 bits of each 32-bit result.
//!
//! Flags affected: None
//!
//! Reference: docs/pmullw.txt

use crate::*;

fn write_mm_via_mem(mem: u64, addr: u64, value: u64) {
    let mut emu = emu64();
    emu.maps.write_qword(addr, value);
}

// ============================================================================
// PMULLW mm, mm/m64 (opcode 0F D5 /r)
// ============================================================================

#[test]
fn test_pmullw_mm_mm_basic() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00, // MOVQ MM0, [0x2000]
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00, // MOVQ MM1, [0x2008]
        0x0f, 0xd5, 0xc1,                               // PMULLW MM0, MM1
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00, // MOVQ [0x2010], MM0
        0xf4,
    ];

    emu.load_code_bytes(&code);

    // 4 words: 1*2=2, 2*3=6, 3*4=12, 4*5=20
    emu.maps.write_qword(0x2000, 0x0004000300020001);
    emu.maps.write_qword(0x2008, 0x0005000400030002);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x0014000C00060002, "PMULLW: basic multiplication");
}

#[test]
fn test_pmullw_low_16_bits() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    // 100 * 100 = 10000 = 0x2710, low 16 bits = 0x2710
    // 1000 * 1000 = 1000000 = 0xF4240, low 16 bits = 0x4240
    emu.maps.write_qword(0x2000, 0x03E8006403E80064);
    emu.maps.write_qword(0x2008, 0x03E8006403E80064);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x4240271042402710, "PMULLW: low 16 bits only");
}

#[test]
fn test_pmullw_signed_positive() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x7FFF00017FFF0001);
    emu.maps.write_qword(0x2008, 0x0002000200020002);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    // 1*2=2, 7FFF*2=FFFE, 1*2=2, 7FFF*2=FFFE
    assert_eq!(result, 0xFFFE0002FFFE0002, "PMULLW: signed positive");
}

#[test]
fn test_pmullw_signed_negative() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    // -1 (0xFFFF) * 2 = -2 (0xFFFE)
    // -2 (0xFFFE) * 3 = -6 (0xFFFA)
    emu.maps.write_qword(0x2000, 0xFFFEFFFFFFFFFFFE);
    emu.maps.write_qword(0x2008, 0x0003000200030002);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0xFFFAFFFEFFFDFFFC, "PMULLW: negative values");
}

#[test]
fn test_pmullw_negative_negative() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    // -1 * -1 = 1, -2 * -2 = 4
    emu.maps.write_qword(0x2000, 0xFFFEFFFFFFFEFFFF);
    emu.maps.write_qword(0x2008, 0xFFFEFFFFFFFEFFFF);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x0004000100040001, "PMULLW: negative * negative");
}

#[test]
fn test_pmullw_zero() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x1234567890ABCDEF);
    emu.maps.write_qword(0x2008, 0x0000000000000000);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x0000000000000000, "PMULLW: multiply by zero");
}

#[test]
fn test_pmullw_by_one() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x1234567890ABCDEF);
    emu.maps.write_qword(0x2008, 0x0001000100010001);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x1234567890ABCDEF, "PMULLW: multiply by one");
}

#[test]
fn test_pmullw_overflow_discarded() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    // 0x8000 * 0x8000 = 0x40000000, low 16 bits = 0x0000
    emu.maps.write_qword(0x2000, 0x8000800080008000);
    emu.maps.write_qword(0x2008, 0x8000800080008000);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x0000000000000000, "PMULLW: overflow discarded");
}

#[test]
fn test_pmullw_mm_m64() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x14, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0x14, 0x25, 0x08, 0x20, 0x00, 0x00, // PMULLW MM2, [0x2008]
        0x0f, 0x7f, 0x14, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x000A000A000A000A);
    emu.maps.write_qword(0x2008, 0x000A000A000A000A);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    // 10 * 10 = 100 = 0x64
    assert_eq!(result, 0x0064006400640064, "PMULLW: memory operand");
}

#[test]
fn test_pmullw_large_positive() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    // 0x7FFF * 0x0002 = 0xFFFE
    emu.maps.write_qword(0x2000, 0x7FFF7FFF7FFF7FFF);
    emu.maps.write_qword(0x2008, 0x0002000200020002);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0xFFFEFFFEFFFEFFFE, "PMULLW: large positive");
}

#[test]
fn test_pmullw_mixed_signs() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x7FFFFFFFFFFF8000);
    emu.maps.write_qword(0x2008, 0x000200020002FFFE);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0xFFFEFFFEFFFE0000, "PMULLW: mixed signs");
}

#[test]
fn test_pmullw_mm3_mm4() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x1c, 0x25, 0x00, 0x20, 0x00, 0x00, // MOVQ MM3, [0x2000]
        0x0f, 0x6f, 0x24, 0x25, 0x08, 0x20, 0x00, 0x00, // MOVQ MM4, [0x2008]
        0x0f, 0xd5, 0xdc,                               // PMULLW MM3, MM4
        0x0f, 0x7f, 0x1c, 0x25, 0x10, 0x20, 0x00, 0x00, // MOVQ [0x2010], MM3
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x0005000400030002);
    emu.maps.write_qword(0x2008, 0x0006000700080009);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    // 2*9=18, 3*8=24, 4*7=28, 5*6=30
    assert_eq!(result, 0x001E001C00180012, "PMULLW: MM3 * MM4");
}

#[test]
fn test_pmullw_powers_of_two() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x0100008000400020);
    emu.maps.write_qword(0x2008, 0x0002000200020002);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x0200010000800040, "PMULLW: powers of two");
}

#[test]
fn test_pmullw_sequential() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,                               // PMULLW MM0, MM1 (first)
        0x0f, 0xd5, 0xc1,                               // PMULLW MM0, MM1 (second)
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x0002000200020002);
    emu.maps.write_qword(0x2008, 0x0003000300030003);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x0012001200120012, "PMULLW: sequential");
}

#[test]
fn test_pmullw_small_values() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x0001000200030004);
    emu.maps.write_qword(0x2008, 0x0004000300020001);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x0004000600060004, "PMULLW: small values");
}

#[test]
fn test_pmullw_max_positive_value() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    // 0x7FFF * 0x7FFF = 0x3FFF0001, low 16 = 0x0001
    emu.maps.write_qword(0x2000, 0x7FFF7FFF7FFF7FFF);
    emu.maps.write_qword(0x2008, 0x7FFF7FFF7FFF7FFF);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x0001000100010001, "PMULLW: max positive squared");
}

#[test]
fn test_pmullw_min_negative_value() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    // -32768 * -32768 = 1073741824 = 0x40000000, low 16 = 0x0000
    emu.maps.write_qword(0x2000, 0x8000800080008000);
    emu.maps.write_qword(0x2008, 0x8000800080008000);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x0000000000000000, "PMULLW: min negative squared");
}

#[test]
fn test_pmullw_by_negative_one() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x0001000200030004);
    emu.maps.write_qword(0x2008, 0xFFFFFFFFFFFFFFFF);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0xFFFFFFFEFFFDFFFC, "PMULLW: multiply by -1");
}

#[test]
fn test_pmullw_asymmetric_values() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x0064000A00640002);
    emu.maps.write_qword(0x2008, 0x000100640002000A);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    // 2*10=20, 100*2=200, 10*100=1000, 100*1=100
    assert_eq!(result, 0x006403E800C80014, "PMULLW: asymmetric values");
}

#[test]
fn test_pmullw_all_mm_registers() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x2c, 0x25, 0x00, 0x20, 0x00, 0x00, // MOVQ MM5, [0x2000]
        0x0f, 0x6f, 0x34, 0x25, 0x08, 0x20, 0x00, 0x00, // MOVQ MM6, [0x2008]
        0x0f, 0xd5, 0xee,                               // PMULLW MM5, MM6
        0x0f, 0x6f, 0x3c, 0x25, 0x10, 0x20, 0x00, 0x00, // MOVQ MM7, [0x2010]
        0x0f, 0xd5, 0xef,                               // PMULLW MM5, MM7
        0x0f, 0x7f, 0x2c, 0x25, 0x18, 0x20, 0x00, 0x00, // MOVQ [0x2018], MM5
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x0002000200020002);
    emu.maps.write_qword(0x2008, 0x0003000300030003);
    emu.maps.write_qword(0x2010, 0x0004000400040004);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2018).unwrap();
    assert_eq!(result, 0x0018001800180018, "PMULLW: all MM registers");
}

#[test]
fn test_pmullw_alternating_pattern() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0xAAAA5555AAAA5555);
    emu.maps.write_qword(0x2008, 0x0002000200020002);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    // 0x5555 * 2 = 0xAAAA, 0xAAAA * 2 = 0x5554 (because signed)
    assert_eq!(result, 0x5554AAAA5554AAAA, "PMULLW: alternating pattern");
}

#[test]
fn test_pmullw_ten_times_ten() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x000A000A000A000A);
    emu.maps.write_qword(0x2008, 0x000A000A000A000A);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    assert_eq!(result, 0x0064006400640064, "PMULLW: 10 * 10");
}

#[test]
fn test_pmullw_overflow_patterns() {
    let mut emu = emu64();
    let code = vec![
        0x0f, 0x6f, 0x04, 0x25, 0x00, 0x20, 0x00, 0x00,
        0x0f, 0x6f, 0x0c, 0x25, 0x08, 0x20, 0x00, 0x00,
        0x0f, 0xd5, 0xc1,
        0x0f, 0x7f, 0x04, 0x25, 0x10, 0x20, 0x00, 0x00,
        0xf4,
    ];

    emu.load_code_bytes(&code);

    emu.maps.write_qword(0x2000, 0x1000100010001000);
    emu.maps.write_qword(0x2008, 0x1000100010001000);

    emu.run(None).unwrap();

    let result = emu.maps.read_qword(0x2010).unwrap();
    // 0x1000 * 0x1000 = 0x1000000, low 16 = 0x0000
    assert_eq!(result, 0x0000000000000000, "PMULLW: overflow patterns");
}