On 22/11/2021 06:40, Jojo R via Gcc wrote:
— Jojo
在 2021年11月20日 +0800 AM6:11，Peter Bergner <berg...@linux.ibm.com>，写道：
On 11/19/21 1:28 AM, Jojo R via Gcc wrote:
We know gcc supply earlyclobber function to avoid register overlap,
but it can not describe explicitly for specific source operand, is it right ?
You add the early clobber to the OUTPUT operand(s) that can clobber any of the
input source operands. You don't mark the source operands that could be
clobbered.
Yes, so we need to enhance the early clobber to cover this scene ?
Peter
You can write alternatives that explicitly tie a source to the
destination, provided that the source and destination are the same size.
See the Arm backend for examples.
R.
