[lld] r251692 - Comments about how values were calculated for functions below were added.

[Rui Ueyama via llvm-commits]

I don't think this comments add much value to the code because it's already
commented well. We have comments just above these new comments to show the
final results of the calculations, so it is very easy to understand the
intention of the code. If you get what we want to get here, it's in my
opinion very easy to understand the code as well.

On Fri, Oct 30, 2015 at 2:11 AM, George Rimar via llvm-commits <
llvm-commits at lists.llvm.org> wrote:

> Author: grimar
> Date: Fri Oct 30 04:11:12 2015
> New Revision: 251692
>
> URL: http://llvm.org/viewvc/llvm-project?rev=251692&view=rev
> Log:
> Comments about how values were calculated for functions below were added.
> 1. X86_64TargetInfo::writePltZeroEntry.
> 2. X86_64TargetInfo::writePltEntry.
>
> Modified:
>     lld/trunk/ELF/Target.cpp
>
> Modified: lld/trunk/ELF/Target.cpp
> URL:
> http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Target.cpp?rev=251692&r1=251691&r2=251692&view=diff
>
> ==============================================================================
> --- lld/trunk/ELF/Target.cpp (original)
> +++ lld/trunk/ELF/Target.cpp Fri Oct 30 04:11:12 2015
> @@ -228,6 +228,10 @@ void X86_64TargetInfo::writePltZeroEntry
>        0xff, 0x25, 0x00, 0x00, 0x00, 0x00, // jmp *GOT+16(%rip)
>        0x0f, 0x1f, 0x40, 0x00              // nopl 0x0(rax)
>    };
> +  // 1. NextPC = PltEntryAddr + 6,
> +  // GotEntryAddr - NextPC + 8 = GotEntryAddr - PltEntryAddr + 2.
> +  // 2. NextPC = PltEntryAddr + 6 + 6,
> +  // GotEntryAddr - NextPC + 16 = GotEntryAddr - PltEntryAddr + 4.
>    memcpy(Buf, PltData, sizeof(PltData));
>    write32le(Buf + 2, GotEntryAddr - PltEntryAddr + 2); // GOT+8
>    write32le(Buf + 8, GotEntryAddr - PltEntryAddr + 4); // GOT+16
> @@ -243,6 +247,12 @@ void X86_64TargetInfo::writePltEntry(uin
>    };
>    memcpy(Buf, Inst, sizeof(Inst));
>
> +  // 1. NextPC = PltEntryAddr + 6,
> +  // GotEntryAddr - NextPC = GotEntryAddr - PltEntryAddr - 6.
> +  // 2. Index is just and index of PLT record.
> +  // 3. NextPC = PltEntryAddr + 6 + 5 + 5 = PltEntryAddr + 16,
> +  // PltEntryAddr - Index * PltEntrySize - PltZeroEntrySize - NextPC =
> +  // -Index * PltEntrySize - PltZeroEntrySize - 16.
>    write32le(Buf + 2, GotEntryAddr - PltEntryAddr - 6);
>    write32le(Buf + 7, Index);
>    write32le(Buf + 12, -Index * PltEntrySize - PltZeroEntrySize - 16);
>
>
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20151031/e7533fee/attachment.html>