Hi all,

In this patch, a new integer register operand modifier 'r' is added. This will use the
proper register name according to the mode of corresponding operand.

'w' register for scalar integer mode smaller than DImode
'x' register for DImode

This allows more flexibility and would meet people's expectations.
It will help for ILP32 and LP64, and big-endian case.

A new section is added to document the AArch64 operand modifiers which might
be used in inline assembly. It's not an exhaustive list covers every modifier.
Only the most common and useful ones are documented.

The default behavior of integer operand without modifier is clearly documented
as well. It's not changed so that the patch shouldn't break anything.

So with this patch, it should resolve the issues in PR63359.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63359


aarch64-none-elf regression test Okay. Okay to check in?

gcc/ChangeLog:

2017-06-06  Renlin Li  <renlin.li@arm.com>

	PR target/63359
	* config/aarch64/aarch64.c (aarch64_print_operand): Add 'r' modifier.
	* doc/extend.texi (AArch64Operandmodifiers): New section.