[LLVMdev] LLVM Disassembler question

[Craig Topper]

The MCInst in this case would contain a value from the instruction enum and
6 operands. One being the dest and another 5 to represent the maximal
address components used by X86 (base, index, scale, displacement, and
segment). The only code that knows how to map those operands is in
lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp. It does this by looking
up TSFlag bits using the enum value and applying rules based on different
bits in the TSFlags.


On Mon, Aug 26, 2013 at 9:18 AM, James Courtier-Dutton <
james.dutton at gmail.com> wrote:

> 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. I then wish to
> apply customized relocation records at the MCInst level.
> My customized relocation records will consist of an byte offset followed
> by an expression of what to replace the following X number of bytes with.
> Much like a normal relocation record.
> I need a way to map relocation byte offsets to the correct operand in
> MCInst.
> The main difference is generally relocation records are applied before
> disassembly, and I wish to do it after disassembly.
>
> Kind Regards
>
> James
>
>
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>
>


-- 
~Craig
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20130826/a90223a5/attachment.html>