[llvm-dev] MC PowerPC 32 bit vs. 64 bit

Alex Bradbury via llvm-dev
Mon, 07 Nov 2016 18:25:52 -0000

On 7 November 2016 at 17:31, Hal Finkel via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
> Hi Keve,
>
> As you've noticed, this is not modeled currently: We should, at least
in theory, be selecting the 64-bit instructions with their associated registers
when in 64-bit mode. Because the assembly is ambiguous in this regard, this does
not matter for the purpose of printing the resulting assembly code (it will look
the same regardless) nor will it matter for the purpose of reassembling the
instructions. This will likely be confusing it you're trying to do analysis
on the disassembled instructions, and I'd be happy to review a patch that
improves our handling here.

This issue has also started to be discussed in the context of
Krzysztof's variable-sized register class proposal:
http://lists.llvm.org/pipermail/llvm-dev/2016-October/105753.html
http://lists.llvm.org/pipermail/llvm-dev/2016-October/105763.html

Best,

Alex