X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gas%2Fdoc%2Fc-mips.texi;h=7ba7496e864f6c6246659d76a385f1ea0e76cc2a;hb=e16bfa71a1a269f19c9a9072ebaa79b4c1718795;hp=dbea72300b191ee1d441eef9dfd13afeb3c396ec;hpb=78849248c05bbfd4aec63ab945195eac6e4224b0;p=deliverable%2Fbinutils-gdb.git

diff --git a/gas/doc/c-mips.texi b/gas/doc/c-mips.texi
index dbea72300b..7ba7496e86 100644
--- a/gas/doc/c-mips.texi
+++ b/gas/doc/c-mips.texi
@@ -26,6 +26,7 @@ Assembly Language Programming'' in the same work.
 * MIPS Object:: 	ECOFF object code
 * MIPS Stabs::  	Directives for debugging information
 * MIPS ISA::    	Directives to override the ISA level
+* MIPS symbol sizes::   Directives to override the size of symbols
 * MIPS autoextend::	Directives for extending MIPS 16 bit instructions
 * MIPS insn::		Directive to mark data as an instruction
 * MIPS option stack::	Directives to save and restore options
@@ -105,6 +106,14 @@ Generate code for the MIPS 16 processor.  This is equivalent to putting
 @samp{.set mips16} at the start of the assembly file.  @samp{-no-mips16}
 turns off this option.
 
+@item -msmartmips
+@itemx -mno-smartmips
+Enables the SmartMIPS extensions to the MIPS32 instruction set, which
+provides a number of new instructions which target smartcard and
+cryptographic applications.  This is equivalent to putting
+@samp{.set smartmips} at the start of the assembly file.
+@samp{-mno-smartmips} turns off this option.
+
 @item -mips3d
 @itemx -no-mips3d
 Generate code for the MIPS-3D Application Specific Extension.
@@ -117,16 +126,32 @@ Generate code for the MDMX Application Specific Extension.
 This tells the assembler to accept MDMX instructions.
 @samp{-no-mdmx} turns off this option.
 
+@item -mdsp
+@itemx -mno-dsp
+Generate code for the DSP Application Specific Extension.
+This tells the assembler to accept DSP instructions.
+@samp{-mno-dsp} turns off this option.
+
+@item -mmt
+@itemx -mno-mt
+Generate code for the MT Application Specific Extension.
+This tells the assembler to accept MT instructions.
+@samp{-mno-mt} turns off this option.
+
 @item -mfix7000
 @itemx -mno-fix7000
 Cause nops to be inserted if the read of the destination register
 of an mfhi or mflo instruction occurs in the following two instructions.
 
-@item -mfix-vr4122-bugs
-@itemx -no-mfix-vr4122-bugs
-Insert @samp{nop} instructions to avoid errors in certain versions of
-the vr4122 core.  This option is intended to be used on GCC-generated
-code: it is not designed to catch errors in hand-written assembler code.
+@item -mfix-vr4120
+@itemx -no-mfix-vr4120
+Insert nops to work around certain VR4120 errata.  This option is
+intended to be used on GCC-generated code: it is not designed to catch
+all problems in hand-written assembler code.
+
+@item -mfix-vr4130
+@itemx -no-mfix-vr4130
+Insert nops to work around the VR4130 @samp{mflo}/@samp{mfhi} errata.
 
 @item -m4010
 @itemx -no-m4010
@@ -197,6 +222,13 @@ identical to @samp{-march=@var{cpu}}.
 Record which ABI the source code uses.  The recognized arguments
 are: @samp{32}, @samp{n32}, @samp{o64}, @samp{64} and @samp{eabi}.
 
+@item -msym32
+@itemx -mno-sym32
+@cindex -msym32
+@cindex -mno-sym32
+Equivalent to adding @code{.set sym32} or @code{.set nosym32} to
+the beginning of the assembler input.  @xref{MIPS symbol sizes}.
+
 @cindex @code{-nocpp} ignored (MIPS)
 @item -nocpp
 This option is ignored.  It is accepted for command-line compatibility with
@@ -238,6 +270,16 @@ error is detected.  This is the default.
 @itemx -mno-pdr
 Control generation of @code{.pdr} sections.  Off by default on IRIX, on
 elsewhere.
+
+@item -mshared
+@itemx -mno-shared
+When generating code using the Unix calling conventions (selected by
+@samp{-KPIC} or @samp{-mcall_shared}), gas will normally generate code
+which can go into a shared library.  The @samp{-mno-shared} option
+tells gas to generate code which uses the calling convention, but can
+not go into a shared library.  The resulting code is slightly more
+efficient.  This option only affects the handling of the
+@samp{.cpload} and @samp{.cpsetup} pseudo-ops.
 @end table
 
 @node MIPS Object
@@ -287,6 +329,61 @@ not by traditional @sc{mips} debuggers (this enhancement is required to fully
 support C++ debugging).  These directives are primarily used by compilers, not
 assembly language programmers!
 
+@node MIPS symbol sizes
+@section Directives to override the size of symbols
+
+@cindex @code{.set sym32}
+@cindex @code{.set nosym32}
+The n64 ABI allows symbols to have any 64-bit value.  Although this
+provides a great deal of flexibility, it means that some macros have
+much longer expansions than their 32-bit counterparts.  For example,
+the non-PIC expansion of @samp{dla $4,sym} is usually:
+
+@smallexample
+lui     $4,%highest(sym)
+lui     $1,%hi(sym)
+daddiu  $4,$4,%higher(sym)
+daddiu  $1,$1,%lo(sym)
+dsll32  $4,$4,0
+daddu   $4,$4,$1
+@end smallexample
+
+whereas the 32-bit expansion is simply:
+
+@smallexample
+lui     $4,%hi(sym)
+daddiu  $4,$4,%lo(sym)
+@end smallexample
+
+n64 code is sometimes constructed in such a way that all symbolic
+constants are known to have 32-bit values, and in such cases, it's
+preferable to use the 32-bit expansion instead of the 64-bit
+expansion.
+
+You can use the @code{.set sym32} directive to tell the assembler
+that, from this point on, all expressions of the form
+@samp{@var{symbol}} or @samp{@var{symbol} + @var{offset}}
+have 32-bit values.  For example:
+
+@smallexample
+.set sym32
+dla     $4,sym
+lw      $4,sym+16
+sw      $4,sym+0x8000($4)
+@end smallexample
+
+will cause the assembler to treat @samp{sym}, @code{sym+16} and
+@code{sym+0x8000} as 32-bit values.  The handling of non-symbolic
+addresses is not affected.
+
+The directive @code{.set nosym32} ends a @code{.set sym32} block and
+reverts to the normal behavior.  It is also possible to change the
+symbol size using the command-line options @option{-msym32} and
+@option{-mno-sym32}.
+
+These options and directives are always accepted, but at present,
+they have no effect for anything other than n64.
+
 @node MIPS ISA
 @section Directives to override the ISA level
 
@@ -310,6 +407,10 @@ The directive @samp{.set mips16} puts the assembler into MIPS 16 mode,
 in which it will assemble instructions for the MIPS 16 processor.  Use
 @samp{.set nomips16} to return to normal 32 bit mode.
 
+The @samp{.set smartmips} directive enables use of the SmartMIPS
+extensions to the MIPS32 @sc{isa}; the @samp{.set nosmartmips} directive
+reverses that.
+
 Traditional @sc{mips} assemblers do not support this directive.
 
 @node MIPS autoextend
@@ -374,4 +475,20 @@ from the MDMX Application Specific Extension from that point on
 in the assembly.  The @code{.set nomdmx} directive prevents MDMX
 instructions from being accepted.
 
+@cindex MIPS DSP instruction generation override
+@kindex @code{.set dsp}
+@kindex @code{.set nodsp}
+The directive @code{.set dsp} makes the assembler accept instructions
+from the DSP Application Specific Extension from that point on
+in the assembly.  The @code{.set nodsp} directive prevents DSP
+instructions from being accepted.
+
+@cindex MIPS MT instruction generation override
+@kindex @code{.set mt}
+@kindex @code{.set nomt}
+The directive @code{.set mt} makes the assembler accept instructions
+from the MT Application Specific Extension from that point on
+in the assembly.  The @code{.set nomt} directive prevents MT
+instructions from being accepted.
+
 Traditional @sc{mips} assemblers do not support these directives.