[Patch ARM] PR47930 Fix documentation for marm / mthumb

[Richard Earnshaw]

On Sun, 2011-03-20 at 15:19 +0000, Ramana Radhakrishnan wrote:
> Hi,
> 
> 	This fixes up documentation for the -marm option and changes the 
> behaviour of mthumb to reject the negative options to bring this to 
> behave similar to the marm option. The option needs to be documented 
> since we now have situations where toolchains default to Thumb state and 
> folks need a way of overriding this. I would like a review of this 
> before committing it since this is a change to the command line options.
> 
> Tested by building a cross toolchain to arm-linux-gnueabi and verified 
> that -mno-thumb is rejected and looking up the documentation after it 
> was rebuilt.
> 
> Ok ?
> 
> cheers
> Ramana
> 
> 
> 2011-03-20  Ramana Radhakrishnan  <ramana.radhakrishnan@linaro.org>
> 
> 	PR target/47930
> 	* config/arm/arm.opt (marm): Document it.
> 	(mthumb): Reject negative variant.

+@item -marm
+@opindex marm
+Generate code for the 32 bit ARM instruction set. This is used to 
+override and generate code in ARM state if the compiler has been 
+configured to be built in Thumb state.  This option is not passed to
the
+assembler. 

I'd suggest

        @item -mthumb
        @itemx -marm
        @opindex marm
        @opindex mthumb
        
        Select between generating code that executes in ARM and Thumb
        states.  The default for most configurations is to generate code
        that executes in ARM state, but the default can be changed by
        configuring GCC with the @option{--with-mode=}@var{state}
        configure option.
        
I don't see any need to talk about the Thumb1/Thumb2 behaviour here any
more than we do about other ISA variants in ARM state.  Nor do I think
it's relevant to talk about this option in relation to the assembler.

The arm.opt change is OK, but 'Report' should stay; and it should also
be added to the -marm case.

R.