Re: [PATCH] ARM: Closing in on unified assembly syntax

[Zack Weinberg <zack at codesourcery dot com>]

Daniel Jacobowitz <drow@false.org> writes:

> On Mon, May 02, 2005 at 11:58:08AM -0700, Zack Weinberg wrote:
>> Ian Lance Taylor <ian@airs.com> writes:
>> 
>> > Zack Weinberg <zack@codesourcery.com> writes:
>> >
>> >>  - Conditional suffixes are accepted, but ignored, on all Thumb
>> >>    instructions.
>> >
>> > Maybe you are implementing to some standard that requires this, but it
>> > looks decidedly odd to me.  I would expect that a conditional suffix
>> > in Thumb mode should cause an error.
>> 
>> It's an intermediate point, useful in itself as it allows correctly
>> written Thumb-2 code to assemble.  The next stage is to validate these
>> conditional suffixes against preceding IT instructions, which actually
>> cause conditional execution.  Here's an example -
>
> To clarify: this only applies when the assembler is in Thumb-2 mode, or
> it applies even in classic Thumb mode?

The present state is that it applies even in classic Thumb mode.
After the validator is implemented, we'll recover the inability to use
conditionalized instructions in classic Thumb mode, because you can't
write IT instructions in that mode.  (That part is already true.)

zw