similar to: [LLVMdev] writeNopData and non-instructions in .text

Hi This patch fixes code generation bug - 586-class CPUs don't support the nopl instruction and some 686-class CPUs don't support it too. I created bug 17792 for that. BTW. I think you should also optimize padding on these CPUs - instead of a stream of 0x90 nops, you should generate variants of "lea (%esi), %esi" instruction like gcc. This patch disables generation of

Please include a testcase with the patch. gas uses " nopl 0x0(%eax)" for k6_2. Are you sure it is a gas bug? On 3 November 2013 13:50, Mikulas Patocka <mikulas at artax.karlin.mff.cuni.cz> wrote: > Hi > > This patch fixes code generation bug - 586-class CPUs don't support the > nopl instruction and some 686-class CPUs don't support it too. > > I

Hi All, While trying to put together an MC-based assembler the other day, I again encountered MC's non-obvious memory ownership rules. The most egregious example of these is MCObjectStreamer's destructor: MCObjectStreamer::~MCObjectStreamer() { delete &Assembler->getBackend(); delete &Assembler->getEmitter(); delete &Assembler->getWriter(); delete Assembler;

Daniel: Thanks for your detailed response. I had seen the discussion from earlier this year, but when I read it, I didn't expect it would be so difficult to get just one bit of information where I wanted it. :-) Thanks for the heads up about clang not necessarily setting ABIname. I have at least enough of that working already that I can generate the appropriate assembly source. After doing a

Thanks a lot Tim. I am getting an error which says: "LLVM ERROR: unable to write nop sequence of 0 bytes" Is there any way that I can print out the Obj code (I mean bitstream representation of the assembly code which is going to be placed in the ELF file), before making any ELF file? Cheers, ES On Tue, Oct 13, 2015 at 3:02 PM, Tim Northover <t.p.northover at gmail.com> wrote:

Hi LLVM and GCC developers, My sincere thanks will goto: * Duncan, the core developer of llvm-gcc and dragonegg http://llvm.org/devmtg/2009-10/Sands_LLVMGCCPlugin.pdf * David, the innovator and developer of GCC https://dmalcolm.fedorapeople.org/gcc/global-state/requirements.html and others who give me kind response for teaching me patiently and carefully about how to migrate GCC v4.8.x to

On Tue, 5 Nov 2013, Rafael Espíndola wrote: > Please include a testcase with the patch. I'm sending testcase here. Compile it with "clang -O2 -march=k6-2 -c loop.c" > gas uses " nopl 0x0(%eax)" for k6_2. Are you sure it is a gas bug? Yes, it is gas bug. I should report it to binutils maintainers. Mikulas > On 3 November 2013 13:50, Mikulas Patocka >

While playing with sanitizer in a downstream project, I found out this. /Users/davide/work/llvm-monorepo/llvm-project-20170507/llvm/tools/llvm-mc-assemble-fuzzer/llvm-mc-assemble-fuzzer.cpp:207:32: error: reference to type 'std::unique_ptr<MCCodeEmitter>' could not bind to an lvalue of type 'llvm::MCCodeEmitter *' UseDwarfDirectory, IP, CE, MAB, ShowInst));

Hi, I've run Clang Static Analyzer checker alpha.cplusplus.NewDeleteLeaks over LLVM codebase to detect false-positives and at the same time eliminate memory leaks. The majority of leaks were detected in lib/Target/* and lib/MC/*. In all cases the similar trick was detected as a leak (example from lib/Target/Sparc/MCTargetDesc/SparcMCTargetDesc.cpp) : static MCStreamer

Hi all, we have several features in Mips that are dependent on target abi. A recent commit(r224492) introduced a new -target-abi option to TargetOptions struct that provides access to abi string. This info is stored in MCSubtarget class(ARMSubratget in this case) and distributed to other libraries. Unfortunately, for Mips we need this info in other classes that don't have access to MCSubtarget

It worked in August. Last time I’ve asked (again, in August) someone did seem to care, but it is inevitable it would bitrot if it’s not built in any of the bots. George > On May 4, 2018, at 2:53 PM, Davide Italiano via llvm-dev <llvm-dev at lists.llvm.org> wrote: > > While playing with sanitizer in a downstream project, I found out this. > >

Hi, I experienced a crash in code compiled with Clang 10.0.0 due to a misaligned 64-bit data access. The (ARMv8) CPU is configured with SCTL.A == 1 (alignment check enable). With SCTLR.A == 0 the code runs as expected. After some investigation I came up with the following reproducer: ---8<-------8<-------8<-------8<-------8<-------8<-------8<------- $ cat test.c extern char

Hi Eric, The main thing we need to fix is that the selection between ELF32/ELF64 needs to depend on the ABI being N64 and not on whether we used a mips-linux-gnu triple versus a mips64-linux-gnu triple. So 'clang -target mips-linux-gnu' -mips64r2 -mabi=64' should produce an ELF64 and 'clang -target mips64-linux-gnu -mips32r2 -mabi=32' should produce an ELF32. In terms of code,

Thank you. I went ahead with a speculative fix in r331568. I'm not familiar _at all_ with the tool, so, although the fix was straightforward, another pair of eyes from somebody familiar with the tool would be appreciated. On Fri, May 4, 2018 at 5:10 PM, George Karpenkov <ekarpenkov at apple.com> wrote: > It worked in August. > Last time I’ve asked (again, in August) someone did

With the MIPS compiler, when we have static constants, in the .s file we get something like: .type $.str33, at object # @.str33 .section .rodata.str1.1,"aMS", at progbits,1 $.str33: .asciz "//" .size $.str33, 3 Currently when we create direct object code we are referencing the symbol as an offset in .rodata and not directly using

Hi Joan, On Mon, 13 May 2019 at 18:01, Joan Lluch <joan.lluch at icloud.com> wrote: > After looking at it a bit further, I think this is a Clang thing. Clang issues “align 2” if the struct has at least one int (2 bytes), but also if the entire struct size is multiple of 2. For example a struct with 4 char members. In these cases the LLVM backend correctly creates word sized load/stores

Hi, I think I discovered a major armv7 optimization bug in Clang. I create a simple test case which exhibits the issue. When you compile the attached file for armv7 with optimizations turned on (O2, O3 or Os), the binary generated led to a crash. The issue can't be reproduced when using GCC 4.2. It can't be reproduced with Clang when the optimization is turned off (O0). This issue can be

Hello, Anton, I'd like to add a small reply regarding this GSoC project that I would like to mentor and I discussed also with Andrei. A good part of our GSoC project is indeed related to this Connex back end that it's not yet part of the LLVM source repository - an important thing proposed in the project is that we plan to perform efficient realignment for this Connex vector

Ping, Apart from Anton's concerns (which I think are manageable) and Micah's support, I received no reply on this. Does there exist a way to tell MC to generate and ELF container for code on Windows? If not, I'm willing to submit a patch to fix this, but would like some opinions on the best direction to take here. The proposed "llvm::TargetSpec class"

Hi Jim, The diff below is not intended to be a patch, but a starting point. It is the shortest path (I hope) to getting LLVM to emit ARM mapping symbols to the ELF without changing any shared interfaces. Could you have a look at the FIXME comments and offer some pointers on how to get this code out of MCELFStreamer? Thanks, Greg diff --git a/lib/MC/MCELFStreamer.cpp b/lib/MC/MCELFStreamer.cpp