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-rw-r--r--gas/doc/c-mips.texi76
1 files changed, 60 insertions, 16 deletions
diff --git a/gas/doc/c-mips.texi b/gas/doc/c-mips.texi
index 7ba7496..383bba4 100644
--- a/gas/doc/c-mips.texi
+++ b/gas/doc/c-mips.texi
@@ -91,19 +91,28 @@ flags force a certain group of registers to be treated as 32 bits wide at
all times. @samp{-mgp32} controls the size of general-purpose registers
and @samp{-mfp32} controls the size of floating-point registers.
+The @code{.set gp=32} and @code{.set fp=32} directives allow the size
+of registers to be changed for parts of an object. The default value is
+restored by @code{.set gp=default} and @code{.set fp=default}.
+
On some MIPS variants there is a 32-bit mode flag; when this flag is
set, 64-bit instructions generate a trap. Also, some 32-bit OSes only
save the 32-bit registers on a context switch, so it is essential never
to use the 64-bit registers.
@item -mgp64
-Assume that 64-bit general purpose registers are available. This is
-provided in the interests of symmetry with -gp32.
+@itemx -mfp64
+Assume that 64-bit registers are available. This is provided in the
+interests of symmetry with @samp{-mgp32} and @samp{-mfp32}.
+
+The @code{.set gp=64} and @code{.set fp=64} directives allow the size
+of registers to be changed for parts of an object. The default value is
+restored by @code{.set gp=default} and @code{.set fp=default}.
@item -mips16
@itemx -no-mips16
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}
+@code{.set mips16} at the start of the assembly file. @samp{-no-mips16}
turns off this option.
@item -msmartmips
@@ -111,7 +120,7 @@ turns off this option.
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.
+@code{.set smartmips} at the start of the assembly file.
@samp{-mno-smartmips} turns off this option.
@item -mips3d
@@ -210,7 +219,29 @@ rm7000,
rm9000,
10000,
12000,
-mips32-4k,
+4kc,
+4km,
+4kp,
+4ksc,
+4kec,
+4kem,
+4kep,
+4ksd,
+m4k,
+m4kp,
+24kc,
+24kf,
+24kx,
+24kec,
+24kef,
+24kex,
+34kc,
+34kf,
+34kx,
+5kc,
+5kf,
+20kc,
+25kf,
sb1
@end quotation
@@ -399,17 +430,21 @@ assembly. @code{.set mips@var{n}} affects not only which instructions
are permitted, but also how certain macros are expanded. @code{.set
mips0} restores the @sc{isa} level to its original level: either the
level you selected with command line options, or the default for your
-configuration. You can use this feature to permit specific @sc{r4000}
+configuration. You can use this feature to permit specific @sc{mips3}
instructions while assembling in 32 bit mode. Use this directive with
care!
-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.
+@cindex MIPS CPU override
+@kindex @code{.set arch=@var{cpu}}
+The @code{.set arch=@var{cpu}} directive provides even finer control.
+It changes the effective CPU target and allows the assembler to use
+instructions specific to a particular CPU. All CPUs supported by the
+@samp{-march} command line option are also selectable by this directive.
+The original value is restored by @code{.set arch=default}.
-The @samp{.set smartmips} directive enables use of the SmartMIPS
-extensions to the MIPS32 @sc{isa}; the @samp{.set nosmartmips} directive
-reverses that.
+The directive @code{.set mips16} puts the assembler into MIPS 16 mode,
+in which it will assemble instructions for the MIPS 16 processor. Use
+@code{.set nomips16} to return to normal 32 bit mode.
Traditional @sc{mips} assemblers do not support this directive.
@@ -419,10 +454,10 @@ Traditional @sc{mips} assemblers do not support this directive.
@kindex @code{.set autoextend}
@kindex @code{.set noautoextend}
By default, MIPS 16 instructions are automatically extended to 32 bits
-when necessary. The directive @samp{.set noautoextend} will turn this
-off. When @samp{.set noautoextend} is in effect, any 32 bit instruction
-must be explicitly extended with the @samp{.e} modifier (e.g.,
-@samp{li.e $4,1000}). The directive @samp{.set autoextend} may be used
+when necessary. The directive @code{.set noautoextend} will turn this
+off. When @code{.set noautoextend} is in effect, any 32 bit instruction
+must be explicitly extended with the @code{.e} modifier (e.g.,
+@code{li.e $4,1000}). The directive @code{.set autoextend} may be used
to once again automatically extend instructions when necessary.
This directive is only meaningful when in MIPS 16 mode. Traditional
@@ -467,6 +502,15 @@ from the MIPS-3D Application Specific Extension from that point on
in the assembly. The @code{.set nomips3d} directive prevents MIPS-3D
instructions from being accepted.
+@cindex SmartMIPS instruction generation override
+@kindex @code{.set smartmips}
+@kindex @code{.set nosmartmips}
+The directive @code{.set smartmips} makes the assembler accept
+instructions from the SmartMIPS Application Specific Extension to the
+MIPS32 @sc{isa} from that point on in the assembly. The
+@code{.set nosmartmips} directive prevents SmartMIPS instructions from
+being accepted.
+
@cindex MIPS MDMX instruction generation override
@kindex @code{.set mdmx}
@kindex @code{.set nomdmx}