The build process runs the tool aapt to automatically create the configuration file bin/proguard.txt, based on AndroidManifest.xml and other xml files. The build process then passes the configuration file to ProGuard. So ProGuard itself indeed doesn’t consider AndroidManifest.xml, but aapt+ProGuard do.
See a 32 bit version in the AMD Software Optimization guide, page 195 for one implementation. This gives you assembly code for an x86 directly. See a variant at Stanford bit-twiddling hacks The Stanford version looks like the best one to me. It looks very easy to code as x86 asm. Neither of these use … Read more
How about this. Compiler is gcc 4.9.0 mingw x64: void triad(float *x, float *y, float *z, const int n) { float k = 3.14159f; intptr_t i; __m256 k4 = _mm256_set1_ps(k); for(i = -n; i < 0; i += 8) { _mm256_store_ps(&z[i+n], _mm256_add_ps(_mm256_load_ps(&x[i+n]), _mm256_mul_ps(k4, _mm256_load_ps(&y[i+n])))); } } gcc -c -O3 -march=corei7 -mavx2 triad.c 0000000000000000 <triad>: 0: … Read more
Accessing local variable or parameter is a single step operation: take a variable located at offset N on the stack. If you function has 2 arguments (simplified): N = 0 – this N = 1 – first argument N = 2 – second argument N = 3 – first local variable N = 4 – … Read more
In modern CPUs, rep stosb‘s and rep movsb‘s microcoded implementation actually uses stores that are wider than 1B, so it can go much faster than one byte per clock. (Note this only applies to stos and movs, not repe cmpsb or repne scasb. They’re still slow, unfortunately, like at best 2 cycles per byte compared … Read more
Just checked in reflector with a release build. The compiler doesn’t remove the unused private methods. There are ways to use a method without the compiler knowledge, like with reflection. So the compiler doesn’t try to guess. It just leaves the methods there. The only private methods the compiler removes are partial methods without implementation. … Read more
My guess is, that in the first case two different branches end up in the same branch-prediction slot on the CPU. If these two branches predict different each time the code will slow down. In the second loop, the added code may just be enough to move one of the branches to a different branch … Read more
Find smallest and largest element in the list. The difference smallest-largest will be minimum. If you’re looking for nonnegative difference, then this is of course at least as hard as checking if the array has two same elements. This is called element uniqueness problem and without any additional assumptions (like limiting size of integers, allowing … Read more
scipy.optimize.least_squares in scipy 0.17 (January 2016) handles bounds; use that, not this hack. Bound constraints can easily be made quadratic, and minimized by leastsq along with the rest. Say you want to minimize a sum of 10 squares Σ f_i(p)^2, so your func(p) is a 10-vector [f0(p) … f9(p)], and also want 0 <= p_i … Read more