proposal: warning for incomplete multichars

2011-10-03 Thread Steve White
Hi! This concerns multiple character integer constants, e.g. 'abcd' as discussed in the C99 standard in subsection 6.4.4.4. We'll call them multichars. First: everybody agrees multichars are non-portable and therefore to be avoided. That said, there are real-life situations where they

Re: speed of simple loops on x86_64 using opencc vs gcc

2011-09-08 Thread Steve White
Hi Richard! On Thu, Sep 8, 2011 at 11:02 AM, Richard Guenther richard.guent...@gmail.com wrote: On Thu, Sep 8, 2011 at 12:31 AM, Steve White stevan.wh...@googlemail.com wrote: Hi, I run some tests of simple number-crunching loops whenever new architectures and compilers arise. These tests

speed of simple loops on x86_64 using opencc vs gcc

2011-09-07 Thread Steve White
Hi, I run some tests of simple number-crunching loops whenever new architectures and compilers arise. These tests on recent Intel architectures show similar performance between gcc and icc compilers, at full optimization. However a recent test on x86_64 showed the open64 compiler outstripping

Re: speed of double-precision divide

2010-01-24 Thread Steve White
(although I knew there are various other issues.) Cheers! On 23.01.10, Richard Guenther wrote: On Sat, Jan 23, 2010 at 6:33 PM, Steve White swh...@aip.de wrote: Hi, Andrew! ... Nevermind icc for the moment, with whatever trick it may be doing. Why is the SSE2 division so slow, compared

speed of double-precision divide

2010-01-23 Thread Steve White
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Re: speed of double-precision divide

2010-01-23 Thread Steve White
be doing. Why is the SSE2 division so slow, compared to multiplication? Change one character in the division test to make a multiplication test. It is an order of magnitude difference in speed. Try it yourself! Thanks! On 23.01.10, Andrew Pinski wrote: On Sat, Jan 23, 2010 at 8:47 AM, Steve White