On Wed, Jul 14, 2010 at 7:08 PM, Ian Lance Taylor <iant@xxxxxxxxxx> wrote: > Search through that Wikipedia entry for the word "phi". > > Ian On Wed, Jul 14, 2010 at 7:13 PM, Georg Lay <avr@xxxxxxxx> wrote: > PHI is Phi-Function where Phi stands for uppercase greek Phi, i.e. Φ in > HTML or \Phi in TeX. It's a concept rather that an abbrev. Thank you all, that now I know what PHI and "PHI function" means, yes, I knew greek letter phi before, but I didn't think about their relations; maybe I should read more before going further, http://www.amazon.com/Advanced-Compiler-Design-Implementation-Muchnick/dp/1558603204 Cheers, > > Suppose you have C code like > > if (a) > x = 1; > else > x = 2; > > In SSA form each variable must not be set more than once (statically). > So new names are introduced for x like x_1 and x_2 > > if (a) > x_1 = 1; > else > x_2 = 2; > > These two values have to be "merged" again to get x. The magic > which does (or expresses) this is denoted as PHI and called > "Phi-Function": > > if (a) > x_1 = 1; > else > x_2 = 2; > > x = PHI (x_1, x_2) > >> I mean: if gccint has a terminology index or table, at least explain >> what it abbreviated for, maybe that would look better; >> just like any technology book has a term glossary, at the end; > > Yes, a glossary would be great. > > Georg
