# Tag Info

### How do you tell whether a binary number is positive or negative?

how do we know that they t2 = 0xfffffff5= -11 and not \$t2 = 4294967285? We don't. They're the same number (in mod 232 arithmetic, which is what your computer uses.) Essentially, signed or unsigned is ...
• 852

### Are float pseudo-random number generators always implemented using integer generators underneath

I am not aware of any direct-to-float PRNGs. The primary issue is that it is very difficult to get high quality random numbers using floating point operations. PRNGs typically leverage well ...
• 3,351
1 vote

### Calculate the CPI of a program

Begin by drawing a table of the instructions executed: # INSN OP1 OP2 OP3 COMMENT 1 addi t0 zero 1 t0 = 1 2 addi v0 zero 0 v0 = 0 3 beq t0 zero exitout t0 != 0 (hit) 4 sll t0 t0 0 (bds) 5 addi ...
1 vote

### Are my ideas good enough to be hired by programming design groups?

What if the user of this malloc is making a node-based datastructure and expects each node to survive multiple calls to its addNode()? I assume that is what the <...
• 4,506
1 vote

### Are float pseudo-random number generators always implemented using integer generators underneath

My very very first computer that came with BASIC built-in, had a random number generator that replaced the previous value x with the fractional part of (x + pi)^5. It wasnâ€™t very random. It had the ...
• 30.5k
1 vote

### Are float pseudo-random number generators always implemented using integer generators underneath

As other answers have pointed out, most PRNGs using floating-point computation and floating-point storage for the PRNG state simply use the floating-point unit to perform integer arithmetic, using the ...
• 520
1 vote

### Are float pseudo-random number generators always implemented using integer generators underneath

Yes. When IBM created its POWER processors which may have been the first ones with a fused multiply-add operation, they managed to implement the linear-congruential method using floating point, ...
• 30.5k
1 vote

### What is the reason or advantage of having special purpose status flags for the result of comparisons?

You have two choices. Either you have separate compare instructions for ==, !=, <, <= etc. which all create 0 or 1, or you have one compare instruction creating flags and various branch ...
• 30.5k
1 vote

### What is the purpose of padding bits in primitive integer types?

IIRC, Crays had a 23 bits integer type. This was really just their 32 bits floating point type with the exponent set to zero/ignored. If this idea sounds outdated, AVX-512 recently introduced a 52 ...
• 895

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