similar to: [LLVMdev] x86 disassembler rejecting valid code

Displaying 20 results from an estimated 6000 matches similar to: "[LLVMdev] x86 disassembler rejecting valid code"

2010 Apr 05
1
[LLVMdev] Fix wrong x86 inst encoding / problem with disassembler
Hello I think I found a bug in the x86 instruction definition file, while trying out the disassembler. It looks like the "ADD32rr_alt" instruction should have GR32 operands, not GR16. Attached you can find a patch, which should fix the problem. But even with the change I can not decode e.g. "0x03 0xC1" (should be "addl %ecx, %eax") only if I remove the
2017 Nov 30
2
PPC64 Disassembler
> But where is the flat set? Maybe I can debug and check what is going on. The MCInstrDesc are in a table in lib/Target/PowerPC/PPCGenInstrInfo.inc of your build directory. > Some additional information: > > MCInst opcode: 0x7cb > Decode Index: 0x1e I had assumed this would have dissembled to '// Inst #234 = BC' which does have the branch flag set, but I think that
2013 Apr 24
0
[LLVMdev] [PATCH] Handle tied sub-operands in AsmMatcherEmitter
Hi Jim, > Thank you for looking at this. Apologies again for taking > unjustifiably long to get back to you. This is really good stuff and > I very much want to see this go in. I like it enough I’m going to > try to talk you into doing even more work on improving this code. ;) > > Fair warning up front: You’re digging into some pretty fundamental > problems in how the
2009 Sep 04
1
[LLVMdev] X86 Disassembler
I was away doing other things for a while, but I have an API patch separated out, which (in addition to being much smaller than past megapatches) corrects two issues Chris identified in his most recent set of patches: - First, it makes the API a good deal simpler. Now, you can instantiate a single MCDisassembler and, each time you want an instruction disassembled, you can simply pass
2013 Apr 23
4
[LLVMdev] [PATCH] Handle tied sub-operands in AsmMatcherEmitter
Hi Ulrich, Thank you for looking at this. Apologies again for taking unjustifiably long to get back to you. This is really good stuff and I very much want to see this go in. I like it enough I’m going to try to talk you into doing even more work on improving this code. ;) Fair warning up front: You’re digging into some pretty fundamental problems in how the assemblers and code generators like to
2016 May 23
0
[BUG] Mismatch between assembler & disassembler of X86 RIP-relative instruction
On Mon, May 23, 2016 at 2:44 PM, Jun Koi <junkoi2004 at gmail.com> wrote: > Hi, > > I found a mismatch between assembler & disassembler of X86: I assembled an > instruction, then disassembled the output, but the result is not the same > as the first original code: "add qword ptr [205163983024656], 1" vs " add > qword ptr [1985229328], 1" > >
2016 May 23
2
[BUG] Mismatch between assembler & disassembler of X86 RIP-relative instruction
Hi, I found a mismatch between assembler & disassembler of X86: I assembled an instruction, then disassembled the output, but the result is not the same as the first original code: "add qword ptr [205163983024656], 1" vs " add qword ptr [1985229328], 1" Anybody knows what is wrong? Thanks. $ echo "ADD QWORD PTR [0xba9876543210], 0x1"|llvm-mc -assemble
2009 Aug 22
0
[LLVMdev] X86 Disassembler
On Aug 19, 2009, at 4:39 PM, Sean Callanan wrote: > thanks for your comments. I'll respond to them individually. I've > attached a new revision of the patch that addresses them. Patch > built and tested against SVN 79487, with the additional attached fix > that fixes an Intel table bug. Thanks Sean, comments below. Are you sure you attached the updated patch? I
2017 Nov 29
3
PPC64 Disassembler
Hi all, I'm working on lldb to make it available to ppc64le, but the "step over" is not working for some cases. When debugging, I can see that the disassembler analyze some instructions forward, looking for a branch instruction (llvm/tools/lldb/source/Plugins/Disassembler/llvm/DisassemblerLLVMC.cpp:87 - "const bool can_branch = mc_disasm_ptr->CanBranch(inst);"), while
2016 Oct 08
3
RFC: Implement variable-sized register classes
On 4 October 2016 at 19:50, Krzysztof Parzyszek via llvm-dev <llvm-dev at lists.llvm.org> wrote: > If there are no objections, I'd like to start working on this soon... > > For the AMDGPU target this implies that RC->getSize will no longer be > available in the MC layer. Another advantage of this work that hasn't been mentioned yet is it will reduce the number of uses
2014 Aug 06
4
[LLVMdev] Looking for ideas on how to make llvm-objdump handle both arm and thumb disassembly from the same object file
Hello Tim, Rafael, Renato and llvmdev, I’m working to get llvm-objdump handle both arm and thumb disassembly from the same object file similarly to how darwin’s otool(1) works. And I’m looking for implementing direction. I spoke to Jim Grosbach about some ideas and he suggested I send out and email about some of the possibilities. Since none of the ones I could think of are pretty he thought
2013 Aug 26
1
[LLVMdev] LLVM Disassembler question
Hi, By way of example, I have the following instruction: 44 8b 80 c8 03 00 00 movl 968(%rax), %r8d 1) How is this represented in MCInst? 2) Is there information in MCInst that would tell me which bytes of the instruction are responsible for the 968? The reason I am asking is that I want to work with the bytes disassembled/decoded to an instruction at MCInst level.
2017 Nov 30
2
PPC64 Disassembler
The `isBranch` flag is already set on the branch instructions. Furthermore, we do use the `isBranch()` query in a few places in the PPC back end, so this does work. Perhaps there's something specific about the lldb usage? Is it somehow possible that the `isBranch()` query is called on the wrong instruction? Would you be able to provide a test case that reproduces the issue? On Thu, Nov 30,
2011 Aug 11
1
[LLVMdev] New ARM disassembler - unpredictable instructions
On Aug 11, 2011, at 1:32 AM, James Molloy wrote: > Hi, > > I’m looking at the new ARM disassembler, and performing testing to see if there are any obvious bugs I can fix. Overall it looks really nice – I’ve only found one obvious bug that I’m packaging up a patch for now. Glad you're liking it! I haven't really done comprehensive testing yet—it passes all the decoding tests
2014 Apr 16
2
[LLVMdev] X86 mmx movq disassembler fail
0x0f 0x6f 0xc8 And 0x0f 0x7f 0xc1 Should both be movq % mm0, % mm1. (AT&T) However, llvm 3.4 at least does not recognise the second variant as being a valid instruction. We are currently compiling up latest src incase it has been fixed. If not, could someone take a look or recommend how to fix? Lee -------------- next part -------------- An HTML attachment was scrubbed... URL:
2010 Dec 16
1
[LLVMdev] x86 disassembler: if-statement with redundant branch
Hi there! In the x86 disassembler I noticed an if-statement with a duplicated branch. Are these intended to be identical? Best regards, Nicolas Kaiser -- diff -ur llvm-2.8.orig/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c llvm-2.8/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c --- llvm-2.8.orig/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c 2010-05-06 22:59:00.000000000 +0200
2012 Jun 06
2
[LLVMdev] MC disassembler for ARM
Hi, I'm considering to use MC disassembler for ARM target in a binary translation project. However after trying some ARM binary and I find that there are a lot of instructions that the disassembler fails to to decoding. Could anyone give me some information about the maturity of ARM disassembler? Thanks! David -------------- next part -------------- An HTML attachment was scrubbed... URL:
2012 Jun 06
0
[LLVMdev] MC disassembler for ARM
On Jun 5, 2012, at 7:44 PM, Fan Dawei <fandawei.s at gmail.com> wrote: > Hi, > > I'm considering to use MC disassembler for ARM target in a binary translation project. However after trying some ARM binary and I find that there are a lot of instructions that the disassembler fails to to decoding. > > Could anyone give me some information about the maturity of ARM
2013 Sep 02
1
[LLVMdev] Disassembler Issue
I'm having trouble getting TableGen to generate disassembler code. The issue is that I have several TableGen definitions that emit the same instruction encoding. This results in TableGen complaining about encoding conflicts (and not handling those instructions). For example, general purpose registers in the architecture I'm targeting can hold floating point or integer values. As such, I
2010 Mar 09
3
[LLVMdev] ARM disassembler
Other than the x86 disassembler effort, is there an ARM disassembler effort going on? It seems that there have been commits for weeks with messages like "add so-and-so instruction to ARM.td for disassembly purposes only"... -- Thanks, Shih-wei -------------- next part -------------- An HTML attachment was scrubbed... URL: