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+@c Copyright (C) 1991, 92-98, 1999 Free Software Foundation, Inc.
+@c This is part of the GAS manual.
+@c For copying conditions, see the file as.texinfo.
+@ifset GENERIC
+@page
+@node M32R-Dependent
+@chapter M32R Dependent Features
+@end ifset
+@ifclear GENERIC
+@node Machine Dependencies
+@chapter M32R Dependent Features
+@end ifclear
+
+@cindex M32R support
+@menu
+* M32R-Opts:: M32R Options
+* M32R-Warnings:: M32R Warnings
+@end menu
+
+@node M32R-Opts
+@section M32R Options
+
+@cindex options, M32R
+@cindex M32R options
+
+The Mitsubishi M32R version of @code{@value{AS}} has a few machine
+dependent options:
+
+@table @code
+@item -m32rx
+@cindex @samp{-m32rx} option, M32RX
+@cindex architecture options, M32RX
+@cindex M32R architecture options
+@code{@value{AS}} can assemble code for several different members of the
+Mitsubishi M32R family. Normally the default is to assemble code for
+the M32R microprocessor. This option may be used to change the default
+to the M32RX microprocessor, which adds some more instructions to the
+basic M32R instruction set, and some additional parameters to some of
+the original instructions.
+
+@item -m32r
+@cindex @samp{-m32r} option, M32R
+@cindex architecture options, M32R
+@cindex M32R architecture options
+This option can be used to restore the assembler's default behaviour of
+assembling for the M32R microprocessor. This can be useful if the
+default has been changed by a previous command line option.
+
+@item -warn-explicit-parallel-conflicts
+@cindex @samp{-warn-explicit-parallel-conflicts} option, M32RX
+Instructs @code{@value{AS}} to produce warning messages when
+questionable parallel instructions are encountered. This option is
+enabled by default, but @code{@value{GCC}} disables it when it invokes
+@code{@value{AS}} directly. Questionable instructions are those whoes
+behaviour would be different if they were executed sequentially. For
+example the code fragment @samp{mv r1, r2 || mv r3, r1} produces a
+different result from @samp{mv r1, r2 \n mv r3, r1} since the former
+moves r1 into r3 and then r2 into r1, whereas the later moves r2 into r1
+and r3.
+
+@item -Wp
+@cindex @samp{-Wp} option, M32RX
+This is a shorter synonym for the @emph{-warn-explicit-parallel-conflicts}
+option.
+
+@item -no-warn-explicit-parallel-conflicts
+@cindex @samp{-no-warn-explicit-parallel-conflicts} option, M32RX
+Instructs @code{@value{AS}} not to produce warning messages when
+questionable parallel instructions are encountered.
+
+@item -Wnp
+@cindex @samp{-Wnp} option, M32RX
+This is a shorter synonym for the @emph{-no-warn-explicit-parallel-conflicts}
+option.
+
+@end table
+
+@node M32R-Warnings
+@section M32R Warnings
+
+@cindex warnings, M32R
+@cindex M32R warnings
+
+There are several warning and error messages that can be produced by
+@code{@value{AS}} which are specific to the M32R:
+
+@table @code
+
+@item output of 1st instruction is the same as an input to 2nd instruction - is this intentional ?
+This message is only produced if warnings for explicit parallel
+conflicts have been enabled. It indicates that the assembler has
+encountered a parallel instruction in which the destination register of
+the left hand instruction is used as an input register in the right hand
+instruction. For example in this code fragment
+@samp{mv r1, r2 || neg r3, r1} register r1 is the destination of the
+move instruction and the input to the neg instruction.
+
+@item output of 2nd instruction is the same as an input to 1st instruction - is this intentional ?
+This message is only produced if warnings for explicit parallel
+conflicts have been enabled. It indicates that the assembler has
+encountered a parallel instruction in which the destination register of
+the right hand instruction is used as an input register in the left hand
+instruction. For example in this code fragment
+@samp{mv r1, r2 || neg r2, r3} register r2 is the destination of the
+neg instruction and the input to the move instruction.
+
+@item instruction @samp{...} is for the M32RX only
+This message is produced when the assembler encounters an instruction
+which is only supported by the M32Rx processor, and the @samp{-m32rx}
+command line flag has not been specified to allow assembly of such
+instructions.
+
+@item unknown instruction @samp{...}
+This message is produced when the assembler encounters an instruction
+which it doe snot recognise.
+
+@item only the NOP instruction can be issued in parallel on the m32r
+This message is produced when the assembler encounters a parallel
+instruction which does not involve a NOP instruction and the
+@samp{-m32rx} command line flag has not been specified. Only the M32Rx
+processor is able to execute two instructions in parallel.
+
+@item instruction @samp{...} cannot be executed in parallel.
+This message is produced when the assembler encounters a parallel
+instruction which is made up of one or two instructions which cannot be
+executed in parallel.
+
+@item Instructions share the same execution pipeline
+This message is produced when the assembler encounters a parallel
+instruction whoes components both use the same execution pipeline.
+
+@item Instructions write to the same destination register.
+This message is produced when the assembler encounters a parallel
+instruction where both components attempt to modify the same register.
+For example these code fragments will produce this message:
+@samp{mv r1, r2 || neg r1, r3}
+@samp{jl r0 || mv r14, r1}
+@samp{st r2, @@-r1 || mv r1, r3}
+@samp{mv r1, r2 || ld r0, @@r1+}
+@samp{cmp r1, r2 || addx r3, r4} (Both write to the condition bit)
+
+@end table