opcodes/arm: use '@' consistently for the comment character

Looking at the ARM disassembler output, every comment seems to start
with a ';' character, so I assumed this was the correct character to
start an assembler comment.

I then spotted a couple of places where there was no ';', but instead,
just a '@' character.  I thought that this was a case of a missing
';', and proposed a patch to add the missing ';' characters.

Turns out I was wrong, '@' is actually the ARM assembler comment
character, while ';' is the statement separator.  Thus this:

    nop    ;@ comment

is two statements, the first is the 'nop' instruction, while the
second contains no instructions, just the '@ comment' comment text.

This:

    nop    @ comment

is a single 'nop' instruction followed by a comment.  And finally,
this:

    nop    ; comment

is two statements, the first contains the 'nop' instruction, while the
second contains the instruction 'comment', which obviously isn't
actually an instruction at all.

Why this matters is that, in the next commit, I would like to add
libopcodes syntax styling support for ARM.

The question then is how should the disassembler style the three cases
above?

As '@' is the actual comment start character then clearly the '@' and
anything after it can be styled as a comment.  But what about ';' in
the second example?  Style as text?  Style as a comment?

And the third example is even harder, what about the 'comment' text?
Style as an instruction mnemonic?  Style as text?  Style as a comment?

I think the only sensible answer is to move the disassembler to use
'@' consistently as its comment character, and remove all the uses of
';'.

Then, in the next commit, it's obvious what to do.

There's obviously a *lot* of tests that get updated by this commit,
the only actual code changes are in opcodes/arm-dis.c.

1 files changed, 18 insertions, 18 deletions

diff --git a/ld/testsuite/ld-arm/tls-thumb1.d b/ld/testsuite/ld-arm/tls-thumb1.d
index 41d5f8c..13fa1c3 100644
--- a/ld/testsuite/ld-arm/tls-thumb1.d
+++ b/ld/testsuite/ld-arm/tls-thumb1.d
@@ -6,17 +6,17 @@ start address 0x.*
 Disassembly of section .plt:
 
 0000813c <.plt>:
-.*:	e52de004 	push	{lr}		; .*
-.*:	e59fe004 	ldr	lr, \[pc, #4\]	; .*
+.*:	e52de004 	push	{lr}		@ .*
+.*:	e59fe004 	ldr	lr, \[pc, #4\]	@ .*
 .*:	e08fe00e 	add	lr, pc, lr
 .*:	e5bef008 	ldr	pc, \[lr, #8\]!
 .*:	000080f0 	.word	0x000080f0
 .*:	e08e0000 	add	r0, lr, r0
 .*:	e5901004 	ldr	r1, \[r0, #4\]
 .*:	e12fff11 	bx	r1
-.*:	e52d2004 	push	{r2}		; .*
-.*:	e59f200c 	ldr	r2, \[pc, #12\]	; .*
-.*:	e59f100c 	ldr	r1, \[pc, #12\]	; .*
+.*:	e52d2004 	push	{r2}		@ .*
+.*:	e59f200c 	ldr	r2, \[pc, #12\]	@ .*
+.*:	e59f100c 	ldr	r1, \[pc, #12\]	@ .*
 .*:	e79f2002 	ldr	r2, \[pc, r2\]
 .*:	e081100f 	add	r1, r1, pc
 .*:	e12fff12 	bx	r2
@@ -26,49 +26,49 @@ Disassembly of section .plt:
 Disassembly of section .text:
 
 00008180 <text>:
-.*:	e59f0004 	ldr	r0, \[pc, #4\]	; .*
+.*:	e59f0004 	ldr	r0, \[pc, #4\]	@ .*
 .*:	ebfffff1 	bl	.* <\.plt\+0x14>
-.*:	e1a00000 	nop			; .*
+.*:	e1a00000 	nop			@ .*
 .*:	000080c0 	.word	0x000080c0
-.*:	4801      	ldr	r0, \[pc, #4\]	; .*
+.*:	4801      	ldr	r0, \[pc, #4\]	@ .*
 .*:	f000 f805 	bl	.* <__unnamed_veneer>
-.*:	46c0      	nop			; .*
+.*:	46c0      	nop			@ .*
 .*:	000080b1 	.word	0x000080b1
 .*:	00000000 	.word	0x00000000
 
 000081a0 <__unnamed_veneer>:
 .*:	4778      	bx	pc
 .*:	e7fd      	b.n	.+ <.+>
-.*:	e59f1000 	ldr	r1, \[pc\]	; .*
+.*:	e59f1000 	ldr	r1, \[pc\]	@ .*
 .*:	e081f00f 	add	pc, r1, pc
 .*:	ffffffa0 	.word	0xffffffa0
 
 Disassembly of section .foo:
 
 04001000 <foo>:
-.*:	e59f0004 	ldr	r0, \[pc, #4\]	; .*
+.*:	e59f0004 	ldr	r0, \[pc, #4\]	@ .*
 .*:	eb000009 	bl	4001030 .*
-.*:	e1a00000 	nop			; .*
+.*:	e1a00000 	nop			@ .*
 .*:	fc00f240 	.word	0xfc00f240
-.*:	e59f0004 	ldr	r0, \[pc, #4\]	; .*
+.*:	e59f0004 	ldr	r0, \[pc, #4\]	@ .*
 .*:	eb000005 	bl	4001030 .*
-.*:	e1a00000 	nop			; .*
+.*:	e1a00000 	nop			@ .*
 .*:	fc00f238 	.word	0xfc00f238
-.*:	4801      	ldr	r0, \[pc, #4\]	; .*
+.*:	4801      	ldr	r0, \[pc, #4\]	@ .*
 .*:	f000 f80b 	bl	400103c .*
-.*:	46c0      	nop			; .*
+.*:	46c0      	nop			@ .*
 .*:	fc00f221 	.word	0xfc00f221
 .*:	00000000 	.word	0x00000000
 
 04001030 <__unnamed_veneer>:
-.*:	e59f1000 	ldr	r1, \[pc\]	; .*
+.*:	e59f1000 	ldr	r1, \[pc\]	@ .*
 .*:	e08ff001 	add	pc, pc, r1
 .*:	fc007114 	.word	0xfc007114
 
 0400103c <__unnamed_veneer>:
 .*:	4778      	bx	pc
 .*:	e7fd      	b.n	.+ <.+>
-.*:	e59f1000 	ldr	r1, \[pc\]	; .*
+.*:	e59f1000 	ldr	r1, \[pc\]	@ .*
 .*:	e081f00f 	add	pc, r1, pc
 .*:	fc007104 	.word	0xfc007104
 .*:	00000000 	.word	0x00000000