search for: pflanzer

Displaying 3 results from an estimated 3 matches for "pflanzer".

2015 Sep 10
3
[OpenCL] Implicit arithmetic conversion of INT_MIN to int vector type
Hello, I recently came across an OpenCL kernel in which an int vector type was subtracted from the INT_MIN constant, e.g. int2 v2 = INT_MIN - (int2)(0); INT_MIN was defined as #define INT_MIN (-2147483648) Clang in OpenCL modes (-x cl) produces the following error: vector_conversion.c:12:42: error: can't convert between vector values of different size ('long' and 'int2'
2015 Sep 13
4
Dynamic detection of signed integer overflow
Hello, I thought about doing a dynamic detection of signed integer overflow for OpenCL kernels based on the generated LLVM IR. A problem seems to be that the LLVM IR does not differentiate between signed and unsigned types in general. But for instance for additions it should be possible to use the "nsw" flag as indicator that the operations involves signed types. Is this a legal
2015 Sep 14
2
Dynamic detection of signed integer overflow
Thanks John, seems like a dynamic runtime instrumentation is then not a good idea. I had a look at the UBSan features in Clang and I might be able to use them instead. But it seems like that vector operations are not instrumented with overflow checks if I specify the option -fsanitize=signed-integer-overflow. Am I missing some other option or is there a special reason why vector operations are not