On 2/17/15 10:48, Chen Gang S wrote: > On 2/17/15 08:11, Chris Metcalf wrote: >> On 2/16/2015 6:46 PM, Peter Maydell wrote: >>> On 17 February 2015 at 08:08, Chen Gang S <gang.c...@sunrus.com.cn> wrote: >>>> On 2/16/15 23:24, Max Filippov wrote: >>>>> Disassembler is not a crucial part of QEMU target. >>>> For me, it is necessary. We need disassemble target binary instructions >>>> (recognize them), then translate them into tcg instructions which are >>>> grouped by Translate Block. >>> No, Max is correct. What QEMU calls the "disassembler" is just >>> used for debug logging: it is code that goes from target binary >>> instructions to printed display of assembly language instructions. >>> This is completely separate code from the code in target-*/translate.c >>> which decodes target binary instructions and emits TCG opcodes. >>> That code is generally called the translator or the decoder, and >>> it is always written from scratch specifically for QEMU. Don't >>> try to reuse code from binutils there. >> >> The kernel disassembly that Chen Gang is looking at is basically just an >> instruction recognizer; it doesn't even include text strings for opcodes, >> for example. But my guess is that it is exactly the right starting building >> block for decoding target binary instructions. >> > > Excuse me, I am not quite familiar with the GPL license, so I guess we > are misunderstanding with each other. > > - it is necessary to disassemble/decode target binary instructions. > > - I want to write the decoder in translate.c according to binutils/ > kernel disassembler (also need consider about "BFD_RELOC" and > "!__KERNEL__ && !__LIBC__"). > > - If I reference to binutils source code, I am not quite sure whether I > break the license or not (is it illegal?). >
Originally, I really wanted to print the disassembly code, although I knew it is optional (not necessary), just like all of you said (and originally, I was not quite sure DISASM_ONLY, either). Thanks. -- Chen Gang Open, share, and attitude like air, water, and life which God blessed