True-False Please indicate whether each statement is True (T) or False (F). 1. T
ID: 674724 • Letter: T
Question
True-False Please indicate whether each statement is True (T) or False (F).
1. The first byte of every x86 machine instruction is the ModR/M byte.
2. In x86 machine instructions, the ModR/M field identifies the addressing mode and operands.
3. The FSTP instruction copies the value in ST(0) to memory, but it does not pop a value off the stack.
4. In the encoding of a MOV from a register to any other operand (89/r), the /r indicates that a Mod R/M byte follows the opcode.
5. The X86 FPU uses a standard for Binary Floating-Point Arithmetic produced by the IEEE organization
6. In a single-precision real number, the exponent uses 7 bits.
7. Not all values between 0 and 1 can be represented by a single-precision significand, but all such values can be represented by an extended-precision significand.
8. There are two types of NaNs, one of which is named Quiet NaN.
9. A double extended-precision real occupies 60 of storage.
10. In a single-precision real, the exponent field has a bias of 128.
11. The binary floating-point number 111.0001 is equivalent to decimal 7 1/8.
12. If we were to denormalize the binary number 1.1101 x 23, the result would be binary 1110.1.
13. The FCOMI instruction compares two floating-point values and sets the Zero, Parity, and Carry flags according to the result of the comparison.
14. After calling the FCOM instruction to compare two floating-point values, you must execute the FNSTSW instruction, followed by FPOP to prepare the CPU to recognize branching instructions such as JG and JL.
15. The single-precision real representation of zero contains zeros in the mantissa and ones in the exponent.
Explanation / Answer
1) True it is true because it follows the opcode and specifies operand..
2) True because the MOD REG-R/M byte specifies instruction operands and their addressing mode..the mod field specifies x86 addressing mode.
3) False The FSTP instruction copies the value in ST(0) to memory, but it does pop a value off the stack. thatz y it is false
4) True because In the encoding of a MOV from a register to any other operand (89/r), the /r indicates that a Mod R/M byte follows the opcode.
5) True
6) True
7) False
8)True
9) False
10) True
11) True
12) True
13) True
14) True