Intel 386 And Amd X86-64 Options - Red Hat ENTERPRISE LINUX 3 - USING GCC Using Instructions

Chapter 4. GCC Command Options
-G
num
On embedded PowerPC systems, put global and static items less than or equal to
the small data or bss sections instead of the normal data or bss section. By default,
switch is also passed to the linker. All modules should be compiled with the same
-G
num
value.
num
-mregnames
-mno-regnames
On embedded PowerPC systems do (do not) emit register names in the assembly language output
using symbolic forms.
-mlongcall
-mno-longcall
Default to making all function calls via pointers, so that functions which reside further than
64 megabytes (67,108,864 bytes) from the current location can be called. This setting can be
overridden by the
Some linkers are capable of detecting out-of-range calls and generating glue code on the fly. On
these systems, long calls are unnecessary and generate slower code. As of this writing, the AIX
linker can do this, as can the GNU linker for PowerPC/64. It is planned to add this feature to the
GNU linker for 32-bit PowerPC systems as well.
In the future, we may cause GCC to ignore all longcall specifications when the linker is known
to generate glue.
-pthread
Adds support for multithreading with the pthreads library. This option sets flags for both the
preprocessor and linker.

4.17.3. Intel 386 and AMD x86-64 Options

These options are defined for the i386 and x86-64 family of computers:
-m
-mtune=
cpu-type
Tune to
cpu-type
set of available instructions. The choices for
,
pentium-mmx
athlon-tbird
.
c3-2
While picking a specific
compiler will not generate any code that does not run on the i386 without the
option being used.
and are the AMD chips as opposed to the Intel ones.
athlon
-march=
cpu-type
Generate instructions for the machine type
as for . Moreover, specifying
-mtune
-mcpu=
cpu-type
A deprecated synonym for
function attribute, or by
shortcall
everything applicable about the generated code, except for the ABI and the
,
pentiumpro pentium2
, ,
athlon-4 athlon-xp
will schedule things appropriately for that particular chip, the
cpu-type
is equivalent to
i586
.
-mtune
#pragma longcall(0)
are
cpu-type
, ,
pentium3 pentium4
, ,
athlon-mp winchip-c6
and
pentium i686
. The choices for
cpu-type
implies
-march=
cpu-type
, , ,
i386 i486 i586 i686
, , ,
k6 k6-2
,
winchip2
-march=
is equivalent to
pentiumpro
cpu-type
-mtune=
cpu-type
95
bytes into
num
is 8. The
num
-G
.
, ,
pentium
, ,
k6-3 athlon
, , and
k8 c3
cpu-type
.
k6
are the same
.