On Sun, Jun 13, 2010 at 4:29 PM, Ilya K <ilya...@gmail.com> wrote: > Hi all. > (I have never used these maillists before. Sorry if something wrong here.) > > I am newbie in gcc and I need some help. > > I am performing some research work in theme of code optimization. > Now I have to write my own optimization pass for gcc. And in this pass > I need to get the instruction codes of the resulting assemble code. > > I put my pass just before the "NEXT_PASS (pass_final);" in > init_optimization_passes function. So I think that asm instructions > are almost ready when my pass starts its work. > This pass is already inserted into the gcc code and can be started. > The gcc is compiled. And I can see my debug stuff in especially > generated file when the gcc works. > Actually I have no useful code yet, but I just want to get some > information for starting the developing. > > For the beginning I want to do something like this: > for (insn = get_insns() ; insn ; insn = NEXT_INSN(insn)) > { > int code = ...; //I need help in this line!!! > myDebugOutputShowCode(++i, code); > } > > I.e. I just want to see the whole list of code of instructions. Like > assembler listing. > > Can you help me and give some advices how to do it? > I had a look at some *.md files in gcc sources, but did not found any > source of codes of assembler instructions. How does the gcc generates > the binary file? Where can it get the binary representation of asm > instruction? > Where is it described that "nop" is "0F 1F" value for x86 architecture > and so on?
GCC does not have an integrated assembler and only outputs assembler source. At the point above you still have RTXen where you can query INSN_CODE to see what instruction from the machine description was matched. In the define_insns there are patterns for generating the assembler source instruction. Richard. > Thanks for any help. >