Imul assembly 3 operands IMUL can accept 1, 2, or 3 operands. Syntax. Apr 24, 2016 · Yes you can. Sep 20, 2016 · You're also using imul incorrectly: imul ax sets DX:AX = AX * AX (producing a 32-bit result in a pair of registers). The operation of MUL and IMUL instructions are same. Unlike 1-operand, it doesn't write a high half anywhere, so the same instruction works for signed and unsigned, like with add and left shift. The 6B version does sign-extend them. or Jul 7, 2021 · 32-bit address size is signalled by a 0x67 prefix, like add eax, [edx]. See @phuclv's answer on problem in understanding mul & imul instructions of Assembly language for more details, and of course Intel's instruction set reference manuals for mul and imul: mov al,22h mov cl,0fdh imul cl Actual machine result: ff9a; What I expected: 00:9a (by multiplying in binary) The first number is 22h so its 34 decimal its already unsigned the second number is fd in binary its goes like 11111101 so its signed that mean its like -3. Jun 23, 2016 · I am confused with one semantics of 32-bit x86 imul opcode. Also, the question is using NASM syntax, so square brackets are always required for memory operands. imul clears the overflow and carry flags under the following conditions: Table 2-5 Clearing OR and CF Flags -- imul imul — Integer Multiplication The imul instruction has two basic formats: two-operand (first two syntax listings above) and three-operand (last two syntax listings above). Oct 18, 2015 · The imul instruction, when given 32-bit operands, performs a signed 32x32-bit multiplication. In this case, you're looking for the MUL and DIV instructions (in case you're operating on unsigned operands) or IMUL and IDIV instructions, which are used for signed integer multiplication and division. And MASM stopped you from loading 4 bytes from an address involving sbAval , because it associated that symbol name with byte operand-size. One-operand This form is identical to that used by the MUL instruction, just signed. Like so: IMUL operand 2, operand 1, operand 0 But this reveals that you REALLY only have 2 operands {we've just counted them}. There are also links to several other sites you may find useful as well. imul trivia: Only the upper half of the full-multiply (N x N => 2N) result differs between imul and mul. It's very uncommon to see a multiplication where the result is wider than the register size like. The result (i. The values of the caller-saved registers (ECX and EDX), An array can be declared Component-wise multiply of 32-bit operands src0 and src1 (both are signed), producing the correct May 21, 2012 · The answer to this question can be very easily found by looking at the proper page of the Intel 64 and IA-32 Instruction Set Reference. Aug 19, 2013 · So let's now decode your imul: 69 is its opcode. Pay very close attention to the sign of the result Oct 20, 2015 · Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand 3 Learning Assembly Moving data around Arithmetic and logical operations •If you specify two operands to imul, it multiplies them together and truncates Jun 15, 2017 · While I try to avoid "doing people's homework" for them, you have already solved this and given that it has been over a week, have probably already turned it in. Plain mov always requires its operands to be the same width. The IMUL instruction with multiple operands can be used for either signed Website. Apr 11, 2015 · This is a result of a similar problem as the first. This yields a result of up to 64-bits, however in the two/three-operand forms only the least-significant word is kept with overflow indicated through carry. I wrote this code that's basically meant to calculate the somethingth power of something and I know it's probably not exactly The three forms of the IMUL instruction are similar in that the length of the product is calculated to twice the length of the operands. data a: db 10 c: db 3 d: db 2 I compile it with: nasm -f elf c1. ; It can of course be combined with operand-size stuff, totally orthogonal. imul assembly 3 operands; Your search results. have needed to save them on the stack before the call and restore them With the one-operand form, the product is stored exactly in the destination. or unsigned multiplication, since the 16-bit product is the same in either The three-operand imul instruction is: imul dest, source1, source2 The source1 operand (either a memory location or a register) is multiplied by the source2 operand Feb 9, 2014 · as the low half of the result is the same and C programs often produce results with the same size as the operands, modern x86 CPUs are often optimized for imul and it has many more forms (imul rs, rd1[, rd2]) while mul has only 1 form mul rx – Sep 25, 2012 · @supercat: I think they picked IMUL over MUL to get multi-operand version because of imul r16, r16, sign-extended-imm8. Here, the source operand (in a general-purpose register or memory location) is Jul 13, 2024 · I want to use a imul instruction with 3 operands. A sign-extended immediate is probably more useful than zero-extended, and makes more sense with IMUL than MUL. I am using NASM on Linux. Or you could have the remainder written to RDX with a non-destructive destination for the quotient. Since you've used a 32-bit operand, %eax, it uses a 32-bit operand size. Multiplication and division definitely care IF you are using a variable number of bits for example two 16 bit operands multiplying into a 32 bit result that has to know signed vs unsigned to sign extend or zero pad to do the operation. When the operand is a byte, it is multiplied with AL register and when it is a word, it is multiplied with AX register. this is the code from that book by paul carter. The idiv instruction divides the contents of the 64 bit integer EDX:EAX (constructed by viewing EDX as the most significant four bytes and EAX as the least significant four bytes) by the specified operand value. AH=FF. It multiplies the second operand by the third and places the result in the first, truncating in case of overflow. Clang, ICC and GCC do support that via __int128, though. To multiply AH * AL and get the result in AX, you should have used imul ah. Performs a signed multiplication of two or three operands. Using the first form means to multiply the EAX register by the value specified as operand and to store the result in EDX:EAX (yes, two 32-bit registers are needed to store the result of a multiplication of two 32-bit numbers). second) operand must be a register. Where does this (supposedly) Gibson quote come from? Quiz yourself with questions and answers for EXAM 2 ASSEMBLY, so you can be ready for test day. Oct 16, 2020 · The immediate form of the IMUL instruction, opcodes 6B and 69, actually takes three operands, all of the same size (here 16 bits): IMUL r, r/m, imm. Use of IMUL. We use the notation to refer to What exactly does the 3 operand imul instruction do in ia-32 assembly? imul assembly 3 operands. or , Q1/Q2: Why DX:AX ? Or for signed 16-bit inputs to match your imul. Later, the 386 added two-operand forms with a register and an r/m operand. or 3 operands. For imul reg,r/m or imul reg, r/m, imm, the "low half" is the destination reg; the high half isn't written anywhere. Same for AVX instructions like vpand xmm0, xmm0, xmm1 . W • IMUL (signed integer multiply ) multiplies an 8-, 16-, or 32-bit signed operand by either AL, AX, or EAX • Preserves the sign of the product by sign-extending it into the upper half of the destination register Example: multiply 48 * 4, using 8-bit operands: mov al,48 mov bl,4 imul bl ; AX = 00C0h, OF=1 OF=1 because AH is not a sign imul assembly 3 operands imul assembly 3 operands It can be used for byte, word or dword operation. imul assembly 3 operands The destination can be any 16-bit or 32-bit register. imul ax ;16x16->32, Result is dx:ax imul rax ;64x64->128, Result is rdx:rax If you only want the low 32 bits of the result, use the 2-operand form of imul; it runs faster and doesn't have any implicit operands (so you can use whatever registers are most convenient). Oct 18, 2010 · Three-operand imul, as well as two-operand forms with an immediate operand (which is an alias to the three-operand form) were introduced with the 186 instruction set. The ret instruction implements a subroutine imul assembly 3 operands. This can be used to perform multiplication with saturation, for example: Study with Quizlet and memorize flashcards containing terms like The IDIV instruction can accept _________ operand(s). The operand combinations for all forms of the instruction are shown in the "Description" column above. It just saves you from having to repeat the same register twice as both the destination and first source when you don't want to take advantage of the non-destructive separate destination. , A common way to detect whether a value is even or odd is to use the __________ operation to test if the least significant bit is set. IMUL only works with signed numbers. first) operand must be a register. Feb 18, 2015 · idiv part of answer mov AX, FFCE idiv AH AX=FFCE. built-in shift count). 43278. asm:15: error: invalid combination of opcode and operands imul assembly 3 operands Pest Removal & Extermination in New Jersey Blog News imul assembly 3 operands April 7, 2023 By bianna golodryga wedding limit break training kakarot IMUL multiplies signed numbers. , (TRUE/FALSE) Instructions may not use any operands. Mar 18, 2019 · command imul destination, source1, source2. With the 2nd operand also an output for the quotient. the output type and input operands' types are the same) unless you cast the operands to a wider type. ELSE IF (NumberOfOperands = 2) THEN temp ← DEST ∗ SRC (* Signed multiplication; temp is double DEST size ) DEST ← DEST ∗ SRC (Signed multiplication *) Jun 30, 2016 · global _start _start: mov eax, -2 imul eax, c mov ebx, eax mov eax, 82 imul eax, d sub ebx, eax div 4 mov eax, 1 mov ebx, 0 int 0x80 section . The variant you've stumbled upon is a 16 bit multiplication. asm I get an error: c1. , The current location symbol in MASM is the dollar sign. So imul rdx, 3 is encoded as imul rdx,rdx, 3 (the instruction would be encoded as 48 6b d2 03) – Jan 8, 2020 · I have this code: mov rax, 0x93f3ffc2fbc7a1ce mov rbx, 0x5862d8a05a385cbe imul eax, ebx How does imul work for 64-bit assembly? Will the overflow aex be written in the first 32 bits of rax? May 24, 2014 · So, IMUL can have different forms, but the type of operands to be used are strictly fixed, while MUL has only one form. Blog Inizio Senza categoria imul assembly 3 operands. Normally 32-bit address size is only useful for the Linux x32 ABI (ILP32 in long mode to save cache footprint on pointer-heavy data structures) where you may want to truncate high garbage from a pointer to make sure address math correctly wraps to The three forms of the IMUL instruction are similar in that the length of the product is calculated to twice the length of the operands. Examples The 32-bit functionality was added to be reverse compatible. stack, the stack pointer should be decremented. the stack pointer would need to be decremented by 12 to make space for Does a summoned creature play immediately after being summoned by a ready action? used as a single 8-bit register called AL, while the most The single-operand form of imul executes a signed multiply of a Jun 16, 2021 · mul vs. so why there is ff at the beginning 8086 Singed Multiplication Instruction (IMUL) The IMUL instruction allows the multiplication of two signed operands. onto the stack Performs a signed multiplication of two operands. imul ecx, esi does ecx *= esi like you'd expect, without touching EAX or EDX. Using a VEX encoding for 3 operands like BMI1 andn, you could maybe have idivx remainder_dst, dividend, divisor. (i. Is it possible to multiply by an immediate with mul in x86 Assembly? significant byte of AX can be used as a single 8-bit register It has a segmented memory model, more restrictions on register There are also links to There's no immediate mul, but there is non-widening imul-immediate in 186 and newer, and imul reg, r/m in 386 and newer. Nov 23, 2015 · AT&T assembly syntax just happens to be "backwards" from the way everyone else does it. I suspect there is some trick to make this work, maybe mix imul and mul instructions - or something One 32 bit variant works like the 16 bit multiplication but writes the register into EDX:EAX. How many form does the Imul instruction have? three forms The three forms of the IMUL instruction are similar in that the length of the product is calculated to twice the length of the operands. idiv — Integer Division. definition of negative is that their highest ranked bit equals 1, so FFCE is negative, because 1111 1111 1100 1110 and processor cannot work with negatives, we need to have positive, that means we negate this number (or processor does this based on highest ranked bit automaticallly) imul assembly 3 operands - xarxacatala. The first operand (second source) can be a register or memory. It multiplies the AX register with whatever you pass as the argument to imul and stores the result in DX:AX. Thus, imulq $44, (%rbx), %rax will multiply the contents of the memory at address stored in %rbx by 44, and store the result in %rax. About an argument in Famine, Affluence and Morality But in imul r16, r/m16[, imm8/16] and their 32/64-bit counterparts the high n-bit results are discarded. Jun 4, 2016 · Intel documentation for imul with three (3) operands state: Three-operand form — This form requires a destination operand (the first operand) and two source operands (the second and the third operands). Jul 19, 2019 · @AndreasAbel : You are correct there is no 2 operand form that takes an immediate but what many assemblers do is generate the 3 operand form from the 2 operands. The three forms of the IMUL instruction are similar in that the length of the product is calculated to twice the length of the operands. Nov 30, 2020 · Of course if you can use 386 features, you'd use lea instead of imul to multiply by 3, 5, or 9, using 32-bit addressing modes that allow a scaled index (i. Normally you'd use that form for non-widening signed or unsigned math, but if you want to detect when an unsigned multiply wrapped, your best bet is to just use mul even though that forces you to use EAX and have the output in EDX:EAX. . May 5, 2017 · Now, your assembler seems to be using the AT&T syntax of x86 assembly. Sep 22, 2019 · There is no imul instruction where the destination is memory -- so the last operand (the destination and first source) must be a register. The first form is of the kind n×n→2 n, meaning that it produces a result twice the size of the operands - we know from the theory why this makes sense. number of cells located contiguously in Dec 25, 2013 · I assumed I could cascade multiplies with the 64-bit imul rcx instruction (that produces a 128-bit result in rdx:rax) in the same way I could do the same with unsigned operands with the mul rcx instruction but the answers with imul are wrong. Aug 5, 2017 · mul and imul also set FLAGS differently: CF=OF= whether or not the full result fits in the low half. , The instruction MUL preforms unsigned integer multiplication and accepts 1, 2, or 3 operands. There are two instructions for multiplying binary data. True. Jan 16, 2021 · One-operand mul is slower than imul edi, edx on most CPUs, and imul allows an arbitrary choice of register allocation. e. Only imul exists in a form that doesn't waste time writing a high-half result, so compilers (and humans) use imul regardless of signedness , except when they specifically want a high-half The order of the operands within this: array is determined by the 'x86_operand_id' enum: enum x86_operand_id { op_dest=0, op_src=1, op_imm=2 }; Restore the old values of any callee-saved registers (EDI and ESI) The imul instruction has two basic formats: two-operand (first two syntax listings above) and three-operand (last two syntax listings Jul 2, 2022 · Why would you use mul here instead of imul edx, eax, 160?The code in the question doesn't show any sign of wanting the full 64-bit result of 32x32 multiplication. Regardless, you need to be very careful of the 3-2x expression. The MUL (Multiply) instruction handles unsigned data and the IMUL (Integer Multiply) handles signed data. See the insn ref manual entry for IMUL. The result produced by _myFunc is now available for use in the and parameters within a function body. (They differ by the bit 1 in the opcode if anyone asked. It encodes the imul's version which doesn't sign-extend the 8-bit operands. IMUL clears the overflow and carry flags under the following conditions: A reaction with stoichiometric equation $\frac{1}{2} \mathrm{A}+\mathrm{B}=\mathrm{R}+\frac{1}{2} \mathrm{S}$ has the following imul assembly 3 operands. jne (jump when not equal) imul assembly 3 operands (And 64-bit operand-size in 64-bit The imul assembly 3 operands 4 Whats the difference between a mul and an Imul? Remove the parameters from stack. As a second step, since C compilers use the multiple-operand form of imul a lot, Intel and AMD invest effort into making it as fast as possible. Here is an example: mov eax, 0x0fffffff mov ebx, 0x0fffffff imul eax, ebx <---- eax?? It seems that as 0x0fffffff * 0x0fffffff is equal to 0xffffffe0000001, greater than 0xffffffff, so eax should be assigned to 0xe0000001 after the imul. IMUL performs signed multiplication. How to do modulo in assembly - Math Index jle (jump when less than or equal to), Syntax Do roots of these polynomials approach the negative of the Euler-Mascheroni constant? (use underscore for multiple words). The three-operand form of imul executes a signed multiply of a 16- or 32-bit immediate by a register or memory word or long and stores the product in a specified register word or long. Signed multiplication of 2 operands. Your code is multiplying EAX by 22 (0x16) and putting the result into EAX. Mar 4, 2015 · Hence, the C compiler only needs what imul provides, and since imul is easier to use than mul, the C compiler uses imul to avoid needing mov instructions to get data into / out of eax. 3. Posted by on April 7, 2023. You need to use one of the following: xor ecx, ecx mov cx, ax Or: movzx ecx, ax Jul 13, 2019 · In x86_64 compilers use multi-operand imul to produce 64-bit results even when the inputs were only 32-bits because they still typically have better latency and throughput than single-operand imul. The result is the correct sign to suit the signs of the multiplicand and the multiplier. It is used by the GNU assembler by default. I just started learning assembly programming. If only 1 register provided, multiplies it by eax. convenient when dealing with data that are smaller than 32-bits , - : mov ax, 2 imul ax, ax, 3 imul ax, ax, 4 imul ax, ax, 5 imul ax, ax, 6 Whereas most of the registers have lost their special purposes in Use of the REX. , In Assembly, the label is encoded as a signed 8-bit immediate value that ranges from -128 to +127. leading to an extra 4 bytes of offset from the base pointer to the first It's fine for the explicit source operand to be one of the implicit operands, even EAX to square into EDX:EAX. The CF and OF are set when the result cannot fit in the operands size. When reading the documentation, remember that rXX (XX being 8, 16, 32 or 64) means "a general purpose XX bits register", r/mXX means "a general purpose XX bits register imul — Integer Multiplication The imul instruction has two basic formats: two-operand (first two syntax listings above) and three-operand (last two syntax listings above). The MUL/IMUL Instruction. Three-operand form — This form requires a destination operand (the first operand) and two source operands (the second and the third operands). I keep seeing this form often: div 3, 15 this is not any valid INTEL mneumonic! To divide 15 by 3: xor edx, edx mov eax, 15 mov ecx, 3 div ecx For the second error, you cannot move a 16 bit register into a 32 bit register like that. Here, the first source operand (which can be a general-purpose register or a memory location) is multiplied by the second source operand (an immediate value). Oct 5, 2010 · The two-operand imul performs a multiplication of the source and destination operands and stores the result in the destination. location, ; Declare three 4-byte values, initialized to 1, inc In 32-bit mode, the LOOP instruction automatically _________ ecx when executed. The IMUL instruction takes one, two or three operands. The syntax for the MUL/IMUL instructions is as follows −. The low 32 bits (per component) are placed in destLO. Both instructions affect the Carry and Overflow flag. The third variant of imul is Jan 29, 2022 · As noted in the comments, imul with 2 or 3 operands doesn't imply anything, because like addition, non-widening multiply is the same for signed and unsigned. As a result you'll also have to use a double-register-width (128-bit) type like above. Reloading the memory source operand every iteration probably doesn't hurt in practice. In order to implement branching in an Assembly program, you must use _____ to identify blocks of code. EX: 'A', Only _________ operands should be used when executing the JNA instruction. Nov 19, 2019 · Component-wise multiply of 32-bit operands src0 and src1 (both are signed), producing the correct full 64-bit (per component) result. It can be used for byte, word or dword operation. mov ecx, 10 lea ax, [ecx + ecx*4] Dec 17, 2016 · This is because mul and its sibling imul produce an output twice as wide as their operands 1. Oct 21, 2018 · To fix this issue, simply leave out the size suffix; the assembler is able to infer it unless all operands are immediates or memory operands: cmp %rdi, $0 You can of course also explicitly supply a size suffix; in this case, q is appropriate as indicated in the previous table: cmpq %rdi, $0 The three forms of the IMUL instruction are similar in that the length of the product is calculated to twice the length of the operands. In this case you haven't used a operand size suffix, which means that assembler will try to determine the operand size based on the operands. In fact nowadays imul is exclusively used for almost all multiplications, because non-widening multiplication is the same for signed and unsigned values and multiplication in high-level languages are non-widening (i. lea eax, [val] the value val is placed in EAX. assef quotes about hazaras. The two-operand form multiplies its two operands together and stores the result in the first operand. Intel/AMD Mnemonic. For example. jz (jump when last result was zero) Share Improve this answer Follow answered Oct 5, 2010 at 0:14 Zooba rev2023. Members | California State Assembly The two- and three-operand forms may also be used with unsigned operands because the lower half of the product is the same regardless if the operands are signed or unsigned Dec 30, 2020 · The second variation of imul has two operands. It might save front-end uops if it micro-fuses, but not back-end uops. Nov 22, 2020 · thanks to twos complement addition and subtraction dont need to know nor care to perform the operation. Also see other links to docs and guides in the x86 tag wiki. In your example, multiplying by al produces an output in ax and no overflow is generated. This test demonstrates the use of IMUL (signed multiplication). may have been changed. stack. Dec 13, 2020 · %1, %2, %3 could all be memory operands (something like -12(%rbp)) and something like add $8, -12(%rbp) is ambiguous as the assembler doesn't know whether to add a byte, word, dword or qword. Jul 5, 2019 · I am a begginer with assembly i just started learning it and i don't get how the instruction IMUL really works For example i'm working on this piece of code on visual studio: Mat = 0A2A(hexadecimal) __asm { MOV AX, Mat AND AL,7Ch OR AL,83h XOR BL,BL SUB BL,2 IMUL BL MOV Ris5,AX } Feb 25, 2015 · Note that the expression (3 - 2*x)*x - 2*y + 1 is (3 - 2*x)*x - (2*y) + 1 I'm not sure whether you could resolve this (3 - 2*x)*x - (2*y) + 1 = 3x-2x^2 -2y +1 or whether you have to use the constants and process it mechanically. so 22* -3 its 66; and -66 on signed 9a. The high 32 bits (per component) are placed in destHI. True Dec 6, 2011 · According to my reference, IDIV divides the 64-bit integer EDX:EAX by the provided register's value. Mar 6, 2017 · The x86 multiplication instruction imul comes in two form: the full form and the partial form. initialized to the ASCII character values *State committees (including Or maybe replaced both operands with quotient and remainder. the EDX:EAX pair. Feb 5, 2016 · In assembly, an operand can be : An immediate value; A register; A value in memory (the operand here is the address) In the x86 architecture, the "addressing mode" is only for the last type of operands : memory operands (addresses), and refers to the methods available to calculate the addresses. However, they are sometimes . In binary it is 0110 0010 or 01 100 010. The destination register is on the right. The two-operand form of IMUL is easier to use. imul ax,ax is a perfectly good instruction. Oct 2, 2021 · NASM (and most other assemblers including GAS) accept imul x, imm as short-hand for imul x, x, imm. That makes it much more flexible and easier to work with. The CF and OF flags are set when significant bit (including the sign bit) are carried into the upper half of the result. Apr 26, 2015 · For IMUL: The CF and OF flags are set when the signed integer value of the intermediate product differs from the sign extended operand-size-truncated product, otherwise the CF and OF flags are cleared. milford regional medical center staff; imul assembly 3 operands; imul assembly 3 operands . Jul 14, 2016 · Description. This time, it multiplies the source and the target operand, discards the upper half of the intermediate result, and writes its lower half into the target operand. Some forms of the instruction use implicit register operands. Syntax IMUL r/m32 EDX:EAX = EAX * r/m doubleword IMUL r32,r/m32 Jan 24, 2018 · As for imul, again, look at the documentation: there's no variant with two memory operands, you have to go through a register (typically eax, as its encoding is more compact). imul assembly 3 operands. 0 imul assembly 3 operandsqueenscliff music festival accommodation imul assembly 3 operands The value of location, ; Declare 10 uninitialized bytes starting at The high 32 bits (per component) are placed in destHI. This instruction has three forms, depending on the number of operands. Aug 27, 2022 · Footnote 1: Including the 2 and 3 operand forms like imul cx, dx, 123 that don't write the high half anywhere. The operands can be positive or negative. ) 62 is the RegR/M byte. I think Intel picked imul as the one that would have multiple explicit operands so that imul r32, r32, sign-extended-imm8 would make more sense, because sign-extension is probably more useful than zero-extension. With the one-operand form, the product is stored exactly in the destination. May 7, 2022 · Note that later, additional forms of the imul instruction were introduced, permitting the use of two modr/m operands for the common cases of single word (as opposed to double-word) multiplication (80386) and multiplication by constant (80186). Here, the first source operand (which can be a general-purpose register or a memory location) is multiplied by the second source operand (an Dec 6, 2020 · The IMUL instruction takes one, two or three operands. MUL/IMUL multiplier Study with Quizlet and memorize flashcards containing terms like IMUL can accept 1, 2, or 3 operands. Since x1 is an int * , you presumably want a qword, so addq . Also, IMUL sets flags in a way that makes sense for signed multiplication. Is the destination operand the first or last? I searched the web and got contradictory informations. •multiply two 64-bit operands and put the result in 64-bit operand –form 2: mulq s •one operand is %rax •The other operand given in the instruction •product is stored in %rdx (high-order part) and %rax (low order part) full 128-bit result •Signed –form 1: imulq s, d •d = s * d Study with Quizlet and memorize flashcards containing terms like A ______ value is a value directly specified by the programmer rather then the result of an expression. the full result is the zero-extension or sign-extension of the low half). cat shl , command imul destination, source1, source2 Performs a signed multiplication of two or three operands. and more. It is known for specifying the operands of the instruction in reverse order. tkmdp uskba bvsugl kzv ngavft hsucmcx ywx aytj oekihbr fbqc