Nicholas Clark wrote:
On Mon, Nov 25, 2002 at 04:51:05PM +0100, Leopold Toetsch wrote:Gopal V wrote:/* ** dotgnu.ops */Thanks applied,I'm surprised that you did your regression tests longhand, rather than having a data table in perl of input and expected output, and auto-generating parrot code.
Writing a few explicit tests is faster ;-)
Is there any speed advantage in truncating by casting via a C type [eg a = (int)(short) b] rather than and on a bitmask [eg a = b & 0xFFFF] ?
gcc uses MOVSX (movs{b,w}l), move byte/word with sign extend to 32 bit. This is listed to take 3 cycles which "and mem" needs too. Inkluding sign extension would be slower then.
We're going to have to do that latter to make it work on Crays anyway, so is a conditional compile to chose between the two worth it?
My Cray is currently out of order ;-) What is special with it?
Nicholas Clark
leo
