On Sun, Mar 12, 2017 at 05:15:54PM +0000, Dibyendu Majumdar wrote: > On 12 March 2017 at 17:10, Luc Van Oostenryck > <luc.vanoostenryck@xxxxxxxxx> wrote: > > On Sun, Mar 12, 2017 at 02:11:37PM +0000, Dibyendu Majumdar wrote: > >> ... > >> > >> My question is: > >> > >> phisrc.64 %phi98(current) <- %r333 > >> > >> The phi98 above is presumably referencing a pseudo which has number > >> 98. But this is not part of this function, so I am confused. Does this > >> look right? > > > > I didn't checked all the details by it looks right. > > > > The %phi98 is not referencing a pseudo which has the number 98. > > It is a pseudo numbered 98 and which is of type PSEUDO_PHI. > > Those kind of pseudos are exclusively created by 'phisrc' instructions > > and used by 'phi' instructions. > > Here this %phi98 is used by the phi instructions at block .L127 > > > > These 'phi' instructions are the core of the SSA representation of > > intermediate code. If needed Wikipedia gives a good introduction: > > https://en.wikipedia.org/wiki/Static_single_assignment_form > > > Thanks. I am familiar with phi instructions in LLVM, but the phisrc > instructions in Sparse are new to me. Good. I wasn't sure. Those phisrc are unimportant, you can consider them as a kind of 'move' which is only but systematically used for each pseudo feeded to a phi instruction. They ahev no special semantic, they just make some things little bit easier for sparse. Luc -- To unsubscribe from this list: send the line "unsubscribe linux-sparse" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
