as: ARM-Instruction-Set

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1 9.4.2.1 Instruction Set Syntax
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1 Two slightly different syntaxes are support for ARM and THUMB
1 instructions.  The default, 'divided', uses the old style where ARM and
1 THUMB instructions had their own, separate syntaxes.  The new, 'unified'
1 syntax, which can be selected via the '.syntax' directive, and has the
1 following main features:
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1    * Immediate operands do not require a '#' prefix.
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1    * The 'IT' instruction may appear, and if it does it is validated
1      against subsequent conditional affixes.  In ARM mode it does not
1      generate machine code, in THUMB mode it does.
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1    * For ARM instructions the conditional affixes always appear at the
1      end of the instruction.  For THUMB instructions conditional affixes
1      can be used, but only inside the scope of an 'IT' instruction.
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1    * All of the instructions new to the V6T2 architecture (and later)
1      are available.  (Only a few such instructions can be written in the
1      'divided' syntax).
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1    * The '.N' and '.W' suffixes are recognized and honored.
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1    * All instructions set the flags if and only if they have an 's'
1      affix.
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