unsigned-integer

I have a C program where I have a few arrays of unsigned ints. I'm using this declaration uint32_t . I want to use SIMD to perform some operations on the data stored in each of the arrays. This is where I'm stuck because it looks like most of the SSE and SSE2 functions only support float and double. What's the best way for me to load data of type uint32_t ? For any integer SSE type you typically use _mm_load_si128 / _mm_loadu_si128 : uint32_t a[N]; __m128i v = _mm_loadu_si128((__m128i *)a); 来源： https://stackoverflow.com/questions/30286685/how-to-load-unsigned-ints-into-simd

I have written this program to perform ulam's conjecture on an entered integer, however when entering a number such as 38836, it exceeds the bounds for a 16 bit signed integer. I believe using unsigned would fix my issue, however I cannot figure out how to adjust this code segment to accept an unsigned integer. Any Help would be very much appreciated! DOSSEG .MODEL SMALL, BASIC, FARSTACK EXTRN GETDEC:FAR EXTRN NEWLINE:FAR EXTRN PUTDEC:FAR EXTRN PUTSTRNG:FAR .STACK 256 .DATA NUM DW ? CNT DW 0 PROMPT DB 'Enter an integer: ' TOTAL DB 'Number Total: ' FLOWMSG DB 'OVERFLOW ' .CODE ULAMS: MOV AX,SEG

This question already has an answer here: Are all integer values perfectly represented as doubles? [duplicate] 5 answers Are there any 64-bit unsigned integer values which cannot be represented with a double-precision floating-point type? (As a double is also 64-bit wide there must be some.) If so, how can I calculate all of them? (In a not brute force way, maybe?) Every integer from 0 to 2^52 inclusive is representable exactly, from 2^52 to 2^53 only every even integer (lowest significant bit of 0), then every fourth integer, up to 2^64-2^12. We could generalise with a bit of code, taking m

For example bool CheckWithinBoundary(int x, int b) { return (x>=0) && (x <= b); } bool CheckWithinBoundary2(int x, int b) { return static_cast<uint32>(x) <= static_cast<uint32>(b); } CheckWithinBoundary2 can save one comparison. My question is: Can today's compiler optimize code using this? Or how can I make the compiler do this kind of optimization? Is there any danger to use this trick? The answer to 2 is, yes, there is, these two are not the same. It seems that you are silently assuming that b >= 0 , too. Consider e.g x == 1 and b == -1 , this would give false for the first case and true

This question already has an answer here: Overflowing of Unsigned Int 3 answers I write the following code: #include <iostream> using namespace std; int main() { unsigned int i=1; i=i-3; cout<<i; return 0; } The output is a garbage value, which is understandable. Now I write the following code: #include <iostream> using namespace std; int main() { unsigned int i=1; i=i-3; i=i+5; cout<<i; return 0; } Now the output is 3. What's happening here? How is the garbage value being added by 5 here? Think of the values of unsigned int being drawn on a large clock face with the largest possible value

Suppose I enter: a = uint8(200) a*2 Then the result is 400, and it is recast to be of type uint16. However: a = array([200],dtype=uint8) a*2 and the result is array([144], dtype=uint8) The multiplication has been performed modulo 256, to ensure that the result stays in one byte. I'm confused about "types" and "dtypes" and where one is used in preference to another. And as you see, the type may make a significant difference in the output. Can I, for example, create a single number of dtype uint8, so that operations on that number will be performed modulo 256? Alternatively, can I create an