Hi Balaji, Its probably better to continue this conversation on gcc@ - so moving it over there.
On Jan 1, 2008 11:40 AM, Balaji V. Iyer <[EMAIL PROTECTED]> wrote: > Dear Ramana, > Thank you very much for your response. I am doing it through > assembler because I want to put specalized control instructions that I > have created to explain the register usage to the processor. These > instructions give information about register usage and liveness > information to the processor. > Now, can these specialized instructions be conveyed in the > machien description of GCC? I have looked through the MD documentation > in the internals document and I hvae not found a way to do so. You can have specialized instructions which are inside unspec's and generate them out of your pass. unspec / unspec_volatile is a nice way to hide any special stuff you want to maintain as a part of your port. > I have noticed that in the assembly passed into the assembler > from GCC, every basic block start is starting with a label. Does it do > anything special (like set a variable or something like that) to > indicate that it has seen a label? Also, any machine dependent function > that can I call during this phase? Also, does it do something like this > in the beginning of a function (since it is sort of a basic block start > in itself) I don't know of any machine dependent function for this purpose , you'll have to add it yourself . Typically instrumentation that happens with fprofile-arcs and gcov is edge based coverage and not node based coverage. > > Thank you very much in advance for all your help... HTH, cheers Ramana > > Yours Sincerely, > > Balaji V. Iyer. > > -- > > Balaji V. Iyer > PhD Student, > Center for Efficient, Scalable and Reliable Computing, > Department of Electrical and Computer Engineering, > North Carolina State University. > > > > -----Original Message----- > From: Ramana Radhakrishnan [mailto:[EMAIL PROTECTED] > Sent: Tuesday, January 01, 2008 12:47 AM > To: Balaji V. Iyer > Cc: [EMAIL PROTECTED] > Subject: Re: GNU Assembler Start of Function & basic block > > Hi, > > > On Jan 1, 2008 3:35 AM, Balaji V. Iyer <[EMAIL PROTECTED]> wrote: > > Hello Everyone, > > I have a question regarding GNU Assembler. > > > > I am currently working with the OpenRISC port of GNU Binutils > > (2.11.92) and I am making some modifications to the ISA. I want to > > insert special instructions at the beginning and end of each basic > > block AND another set of special instructions at the beginning and end > > > of function (I tried to do it in GCC and I was unsuccessful in > > representing these instructions in the machine description). > > I don't think the assembler can help you figure out the basic blocks by > default. You would have to write code to detect basic blocks and then > add these instructions. I'd suggest you use GCC for such > instrumentation. > > For functions its easy - you have to modify your expand_{pro/epi}logue > functions for doing this if you have RTL based prologue and epilogues > based on command line switches. > > For basic blocks you might choose to look at the coverage options to > figure this out (fprofile-arcs and their friends).Or you could write a > pass that was in cfglayout mode to insert these special instructions. > Anyways this discussion is more relevant to the GCC list , so you could > continue it there. > > HTH, > > cheers > Ramana > > > > > I looked through the GNU Assembler Internals manual and I couldn't > > find any specialized functions that can be used to access the start > > and end of each basic block OR function-call (I may have missed > something...). > > Can someone please point me in the right direction? > > > > Any help is greatly appreciated! > > > > Thanks in advance, > > > > Yours Sincerely, > > > > Balaji V. Iyer. > > > > -- > > > > Balaji V. Iyer > > PhD Student, > > Center for Efficient, Scalable and Reliable Computing, Department of > > Electrical and Computer Engineering, North Carolina State University. > > > > > > > > -- > Ramana Radhakrishnan > > -- Ramana Radhakrishnan
