On Sat, Mar 19, 2016 at 9:51 PM, James Molloy via llvm-dev < llvm-dev at lists.llvm.org> wrote:> Hi Lorenzo, > > Clang doesn't call llc; LLVM is compiled into Clang. Clang does call the > system linker though. > > Making your compiler generate *object* code is very simple. Making it > fixup that object code and execute it in memory (JIT style) is also simple. > Linking it properly and creating a fixed up ELF file is less simple. For > that, you need to compile to object (using addPassesToEmitFile() - see > llc.cpp) then invoke a linker. Getting that command line right can be quite > difficult. > > Rafael, This would be a good usecase for LLD as a library. I heard that > this is is an explicit non-goal, which really surprised me. Is that indeed > the case? >You can use LLD as a library. https://github.com/llvm-mirror/lld/blob/master/docs/NewLLD.rst#the-elf-linker-as-a-library> Cheers, > > James > > On Sat, 19 Mar 2016 at 13:32 Lorenzo Laneve via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > >> I'd like to make my compiler independent, just like Clang. Doesn't Clang >> call llc and then system's ld by itself? I don't want my compiler to depend >> by any other program. >> I guess there will be a class in the llvm library that generates the >> object files based on the system's triple and data layout, and then call >> the system's ld? >> >> On Mar 19, 2016, at 11:48 AM, Bruce Hoult <bruce at hoult.org> wrote: >> >> If you've created a .bc or a .ll file then the simplest thing is to just >> give it to clang exactly the same as you would for a .c file. Clang will >> just Do The Right Thing with it. >> >> If you don't want to link, then pass flags such as -c to clang as usual. >> >> e.g. >> >> ---- hello.ll ---- >> declare i32 @puts(i8*) >> @str = constant [12 x i8] c"Hello World\00" >> >> define i32 @main() { >> %1 = call i32 @puts(i8* getelementptr inbounds ([12 x i8]* @str, i64 0, >> i64 0)) >> ret i32 0 >> } >> ---------------- >> >> $ clang hello.ll -o hello && ./hello >> warning: overriding the module target triple with >> x86_64-apple-macosx10.10.0 >> 1 warning generated. >> Hello World >> >> >> On Sat, Mar 19, 2016 at 3:03 AM, Lorenzo Laneve via llvm-dev < >> llvm-dev at lists.llvm.org> wrote: >> >>> I wrote my compiler and now it generates LLVM IR modules. Now i’d like >>> to go ahead and make object file and then executable, just like clang does. >>> >>> What should I have to use to create the object files? and then how do I >>> call the ld? (not llvm-ld, I want my compiler to work like Clang and I read >>> that Clang doesn’t use llvm-ld). >>> _______________________________________________ >>> LLVM Developers mailing list >>> llvm-dev at lists.llvm.org >>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >>> >> >> _______________________________________________ >> LLVM Developers mailing list >> llvm-dev at lists.llvm.org >> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >> > > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev > >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20160321/fdc19888/attachment.html>
> A corrupted file could cause a fatal error or SEGV.Uhhh, that's not particularly useful. On Mon, 21 Mar 2016 at 19:02 Rui Ueyama <ruiu at google.com> wrote:> On Sat, Mar 19, 2016 at 9:51 PM, James Molloy via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > >> Hi Lorenzo, >> >> Clang doesn't call llc; LLVM is compiled into Clang. Clang does call the >> system linker though. >> >> Making your compiler generate *object* code is very simple. Making it >> fixup that object code and execute it in memory (JIT style) is also simple. >> Linking it properly and creating a fixed up ELF file is less simple. For >> that, you need to compile to object (using addPassesToEmitFile() - see >> llc.cpp) then invoke a linker. Getting that command line right can be quite >> difficult. >> >> Rafael, This would be a good usecase for LLD as a library. I heard that >> this is is an explicit non-goal, which really surprised me. Is that indeed >> the case? >> > > You can use LLD as a library. > > https://github.com/llvm-mirror/lld/blob/master/docs/NewLLD.rst#the-elf-linker-as-a-library > > >> Cheers, >> >> James >> >> On Sat, 19 Mar 2016 at 13:32 Lorenzo Laneve via llvm-dev < >> llvm-dev at lists.llvm.org> wrote: >> >>> I'd like to make my compiler independent, just like Clang. Doesn't Clang >>> call llc and then system's ld by itself? I don't want my compiler to depend >>> by any other program. >>> I guess there will be a class in the llvm library that generates the >>> object files based on the system's triple and data layout, and then call >>> the system's ld? >>> >>> On Mar 19, 2016, at 11:48 AM, Bruce Hoult <bruce at hoult.org> wrote: >>> >>> If you've created a .bc or a .ll file then the simplest thing is to just >>> give it to clang exactly the same as you would for a .c file. Clang will >>> just Do The Right Thing with it. >>> >>> If you don't want to link, then pass flags such as -c to clang as usual. >>> >>> e.g. >>> >>> ---- hello.ll ---- >>> declare i32 @puts(i8*) >>> @str = constant [12 x i8] c"Hello World\00" >>> >>> define i32 @main() { >>> %1 = call i32 @puts(i8* getelementptr inbounds ([12 x i8]* @str, i64 >>> 0, i64 0)) >>> ret i32 0 >>> } >>> ---------------- >>> >>> $ clang hello.ll -o hello && ./hello >>> warning: overriding the module target triple with >>> x86_64-apple-macosx10.10.0 >>> 1 warning generated. >>> Hello World >>> >>> >>> On Sat, Mar 19, 2016 at 3:03 AM, Lorenzo Laneve via llvm-dev < >>> llvm-dev at lists.llvm.org> wrote: >>> >>>> I wrote my compiler and now it generates LLVM IR modules. Now i’d like >>>> to go ahead and make object file and then executable, just like clang does. >>>> >>>> What should I have to use to create the object files? and then how do I >>>> call the ld? (not llvm-ld, I want my compiler to work like Clang and I read >>>> that Clang doesn’t use llvm-ld). >>>> _______________________________________________ >>>> LLVM Developers mailing list >>>> llvm-dev at lists.llvm.org >>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >>>> >>> >>> _______________________________________________ >>> LLVM Developers mailing list >>> llvm-dev at lists.llvm.org >>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >>> >> >> _______________________________________________ >> LLVM Developers mailing list >> llvm-dev at lists.llvm.org >> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >> >>-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20160321/5ff7f050/attachment.html>
On Mon, Mar 21, 2016 at 8:04 PM, James Molloy <james at jamesmolloy.co.uk> wrote:> > A corrupted file could cause a fatal error or SEGV. > > Uhhh, that's not particularly useful. >"Corrupted" means really corrupted, like ELF header is broken. Is this really the case?> On Mon, 21 Mar 2016 at 19:02 Rui Ueyama <ruiu at google.com> wrote: > >> On Sat, Mar 19, 2016 at 9:51 PM, James Molloy via llvm-dev < >> llvm-dev at lists.llvm.org> wrote: >> >>> Hi Lorenzo, >>> >>> Clang doesn't call llc; LLVM is compiled into Clang. Clang does call the >>> system linker though. >>> >>> Making your compiler generate *object* code is very simple. Making it >>> fixup that object code and execute it in memory (JIT style) is also simple. >>> Linking it properly and creating a fixed up ELF file is less simple. For >>> that, you need to compile to object (using addPassesToEmitFile() - see >>> llc.cpp) then invoke a linker. Getting that command line right can be quite >>> difficult. >>> >>> Rafael, This would be a good usecase for LLD as a library. I heard that >>> this is is an explicit non-goal, which really surprised me. Is that indeed >>> the case? >>> >> >> You can use LLD as a library. >> >> https://github.com/llvm-mirror/lld/blob/master/docs/NewLLD.rst#the-elf-linker-as-a-library >> >> >>> Cheers, >>> >>> James >>> >>> On Sat, 19 Mar 2016 at 13:32 Lorenzo Laneve via llvm-dev < >>> llvm-dev at lists.llvm.org> wrote: >>> >>>> I'd like to make my compiler independent, just like Clang. Doesn't >>>> Clang call llc and then system's ld by itself? I don't want my compiler to >>>> depend by any other program. >>>> I guess there will be a class in the llvm library that generates the >>>> object files based on the system's triple and data layout, and then call >>>> the system's ld? >>>> >>>> On Mar 19, 2016, at 11:48 AM, Bruce Hoult <bruce at hoult.org> wrote: >>>> >>>> If you've created a .bc or a .ll file then the simplest thing is to >>>> just give it to clang exactly the same as you would for a .c file. Clang >>>> will just Do The Right Thing with it. >>>> >>>> If you don't want to link, then pass flags such as -c to clang as usual. >>>> >>>> e.g. >>>> >>>> ---- hello.ll ---- >>>> declare i32 @puts(i8*) >>>> @str = constant [12 x i8] c"Hello World\00" >>>> >>>> define i32 @main() { >>>> %1 = call i32 @puts(i8* getelementptr inbounds ([12 x i8]* @str, i64 >>>> 0, i64 0)) >>>> ret i32 0 >>>> } >>>> ---------------- >>>> >>>> $ clang hello.ll -o hello && ./hello >>>> warning: overriding the module target triple with >>>> x86_64-apple-macosx10.10.0 >>>> 1 warning generated. >>>> Hello World >>>> >>>> >>>> On Sat, Mar 19, 2016 at 3:03 AM, Lorenzo Laneve via llvm-dev < >>>> llvm-dev at lists.llvm.org> wrote: >>>> >>>>> I wrote my compiler and now it generates LLVM IR modules. Now i’d like >>>>> to go ahead and make object file and then executable, just like clang does. >>>>> >>>>> What should I have to use to create the object files? and then how do >>>>> I call the ld? (not llvm-ld, I want my compiler to work like Clang and I >>>>> read that Clang doesn’t use llvm-ld). >>>>> _______________________________________________ >>>>> LLVM Developers mailing list >>>>> llvm-dev at lists.llvm.org >>>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >>>>> >>>> >>>> _______________________________________________ >>>> LLVM Developers mailing list >>>> llvm-dev at lists.llvm.org >>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >>>> >>> >>> _______________________________________________ >>> LLVM Developers mailing list >>> llvm-dev at lists.llvm.org >>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >>> >>>-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20160321/a1b4d4cd/attachment.html>