_ExtInt is an exact bit-width data type in C and C++ supported by the Clang compiler.
_ExtInt runs on LLVM's any size int. You can make 1 to 16,777,215 bit integers.
Questions tagged [extint]
10 questions
15
votes
2 answers
256-bit arithmetic in Clang (extended integers)
I'm in the design phase of a project that needs to do a lot of simple 256-bit integer arithmetic (add, sub, mul, div only) and need something that is reasonably well optimised for these four operations.
I'm already familiar with GMP, NTL and most of…
Owen2020
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3
votes
2 answers
How do you printf _ExtInt without using casts?
I was wondering how you could printf _ExtInts in clang without using casts. Something like this:
#include
int main() {
_ExtInt(13) foo = 100;
printf("%???", foo);
}
With casts, it would look like this (this is not what I…
xilpex
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3
votes
1 answer
How do you use clang's new custom size int feature?
Recently, I heard that clang got a new feature, _ExtInt. I know that it lets you specify the size of an integer (odd or even like 13-bit int), but how do you use it?
xilpex
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2
votes
1 answer
Does clang have _ExtFloat just like it has _ExtInt?
I've recently been looking into clang's _ExtInt feature (allows you to declare any size int) a lot and was just wondering if there is also an _ExtFloat which I could use to create custom size floats.
xilpex
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2
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2 answers
Will clangs custom int size feature ever get added to gcc?
I was wondering whether clang's new amazing custom size (things like 13-bit int, or 70-bit int, etc.) will get added to gcc.
xilpex
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1
vote
1 answer
_ExtInt(256) doesn't work in CLang 14, but works in CLang 13
When CLang 14 was released I noticed that following code doesn't compile anymore (but works in CLang 13):
Try it online!
int main() { using T = _ExtInt(256); }
This code was used to create fixed size integers of arbitrary bit length, even of…
Arty
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1
vote
2 answers
How to initialize an _Extint() from an hardcoded litteral?
The rust project I m using depends on fixed_hash 0.2.2. And I would need to compare one H160 against a literal (mode exactly know if my_var==0xdac17f958d2ee523a2206206994597c13d831ec7).
Internally, the H160 type is just a pointer to a plain integer…
user2284570
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0
votes
0 answers
Performance of Clang's _bitInt(256) vs Boost Multiprecision int256_t
I'm after the fastest 256 bit integer library (which isn't a nightmare to integrate).
As part of this I'm trying to get a rough idea of the performance comparison between Clang's _Bitint(256) and Boost multiprecision's int256_t.
I've currently got…
intrigued_66
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AVR simulator: XINT0 behaves not as expected
When simulating my ATTiny13 application in AVR Studio7 (latest version 7.0.2594, no stimuli file), XINT0 does not respond as I would expect:
In MCUCR I set ISC01|ISC00 to 0x02 because I want to trigger on the falling edge of XINT0.
When manipulating…
Wallace and Gromit
- 49
- 2
0
votes
1 answer
How to make dynamic bit width integers in C?
I want to represent extended integers and came across _BitInt() but it doesn't work dynamically.
I'm trying to do something like this:
void fun(int n)
{
_BitInt(n)* val = malloc(n); //doesn't work
}
I understand that everything stored on the…
Abdulmalek Almkainzi
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