bfd/

[deliverable/binutils-gdb.git] / gas / doc / c-arm.texi

diff --git a/gas/doc/c-arm.texi b/gas/doc/c-arm.texi
index 5b67f97bac574415149b805028216ba0beb517fd..e871d2821b2ce80b8f27767e6c2e877ad1dbe867 100644 (file)
--- a/gas/doc/c-arm.texi
+++ b/gas/doc/c-arm.texi
@@ -1,4 +1,4 @@
-@c Copyright 1996, 1997, 1998, 1999, 2000, 2001
+@c Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2003
 @c Free Software Foundation, Inc.
 @c This is part of the GAS manual.
 @c For copying conditions, see the file as.texinfo.
@@ -22,6 +22,7 @@
 * ARM Floating Point::       Floating Point
 * ARM Directives::           ARM Machine Directives
 * ARM Opcodes::              Opcodes
+* ARM Mapping Symbols::      Mapping Symbols
 @end menu
 
 @node ARM Options
@@ -80,6 +81,8 @@ recognized:
 @code{arm940t},
 @code{arm9tdmi},
 @code{arm9e},
+@code{arm926e},
+@code{arm926ejs},
 @code{arm946e-r0},
 @code{arm946e},
 @code{arm966e-r0},
@@ -88,9 +91,13 @@ recognized:
 @code{arm10e},
 @code{arm1020},
 @code{arm1020t},
-@code{arm1020e}, 
+@code{arm1020e},
+@code{arm1026ejs},
+@code{arm1136js},
+@code{arm1136jfs},
 @code{ep9312} (ARM920 with Cirrus Maverick coprocessor),
 @code{i80200} (Intel XScale processor)
+@code{iwmmxt} (Intel(r) XScale processor with Wireless MMX(tm) technology coprocessor)
 and
 @code{xscale}.  
 The special name @code{all} may be used to allow the
@@ -102,6 +109,7 @@ co-processor instruction space.  For example, @code{-mcpu=arm920+maverick}
 is equivalent to specifying @code{-mcpu=ep9312}.  The following extensions
 are currently supported: 
 @code{+maverick}
+@code{+iwmmxt}
 and
 @code{+xscale}.
 
@@ -125,7 +133,10 @@ names are recognized:
 @code{armv5t},
 @code{armv5txm},
 @code{armv5te},
-@code{armv5texp}
+@code{armv5texp},
+@code{armv6},
+@code{armv6j},
+@code{iwmmxt}
 and
 @code{xscale}.
 If both @code{-mcpu} and
@@ -157,9 +168,11 @@ The following format options are recognized:
 @code{vfp10-r0},
 @code{vfp9},
 @code{vfpxd},
-@code{arm1020t}
+@code{arm1020t},
+@code{arm1020e},
+@code{arm1136jfs}
 and
-@code{arm1020e}.
+@code{maverick}.
 
 In addition to determining which instructions are assembled, this option
 also affects the way in which the @code{.double} assembler directive behaves
@@ -196,7 +209,7 @@ use this to determine the ABI being used by.
 
 @cindex @code{-mapcs-float} command line option, ARM
 @item -mapcs-float
-This indicates the the floating point variant of the APCS should be
+This indicates the floating point variant of the APCS should be
 used.  In this variant floating point arguments are passed in FP
 registers rather than integer registers.
 
@@ -205,6 +218,25 @@ registers rather than integer registers.
 This indicates that the reentrant variant of the APCS should be used.
 This variant supports position independent code.
 
+@cindex @code{-mfloat-abi=} command line option, ARM
+@item -mfloat-abi=@var{abi}
+This option specifies that the output generated by the assembler should be
+marked as using specified floating point ABI.
+The following values are recognized:
+@code{soft},
+@code{softfp}
+and
+@code{hard}.
+
+@cindex @code{-eabi=} command line option, ARM
+@item -meabi=@var{ver}
+This option specifies which EABI version the produced object files should
+conform to.
+The following values are recognised:
+@code{gnu}
+and
+@code{3}.
+
 @cindex @code{-EB} command line option, ARM
 @item -EB
 This option specifies that the output generated by the assembler should
@@ -300,6 +332,20 @@ example:
         foo .req r0
 @end smallexample
 
+@cindex @code{unreq} directive, ARM
+@item .unreq @var{alias-name}
+This undefines a register alias which was previously defined using the
+@code{req} directive.  For example:
+
+@smallexample
+        foo .req r0
+        .unreq foo
+@end smallexample
+
+An error occurs if the name is undefined.  Note - this pseudo op can
+be used to delete builtin in register name aliases (eg 'r0').  This
+should only be done if it is really necessary.
+
 @cindex @code{code} directive, ARM
 @item .code @code{[16|32]}
 This directive selects the instruction set being generated. The value 16
@@ -422,3 +468,32 @@ For information on the ARM or Thumb instruction sets, see @cite{ARM
 Software Development Toolkit Reference Manual}, Advanced RISC Machines
 Ltd.
 
+@node ARM Mapping Symbols
+@section Mapping Symbols
+
+The ARM ELF specification requires that special symbols be inserted
+into object files to mark certain features:
+
+@table @code
+
+@cindex @code{$a}
+@item $a
+At the start of a region of code containing ARM instructions.
+
+@cindex @code{$t}
+@item $t
+At the start of a region of code containing THUMB instructions.
+
+@cindex @code{$d}
+@item $d
+At the start of a region of data.
+
+@end table
+
+The assembler will automatically insert these symbols for you - there
+is no need to code them yourself.  Support for tagging symbols ($b,
+$f, $p and $m) which is also mentioned in the current ARM ELF
+specification is not implemented.  This is because they have been
+dropped from the new EABI and so tools cannot rely upon their
+presence.
+