Use GCC's __attribute__((const)) to reduce code size

__attribute__((const)) is mainly intended for the compiler to optimize
away repeated calls to a function that the compiler knows will return
the same value repeatedly.

By adding __attribute__((const)), the compiler can choose to call the
function just once and cache the return value.  Therefore, this yields
code size reduction.

Here are the reference results by arm-eabi-size for crespo device:

[before]
   text    data     bss     dec     hex filename
 267715   10132   45948  323795   4f0d3

[after]
   text    data     bss     dec     hex filename
 267387   10132   45948  323467   4ef8b

Change-Id: I1d80465c0f88158449702d4dc6398a130eb77195
getopt(): fix missing carriage return on bad parameters

This affect all command line tools which show the usage on stdout
after an invalid parameter error (printed on stderr)

Change-Id: I8e2cb3fda241ab989dc42055f15082f8b3ba1397
Signed-off-by: Tanguy Pruvot <tanguy.pruvot@gmail.com>
headers: Unbreak some ARM syscalls

Restore the outside-kernel exclusion for some syscalls that was
removed by change I959b64280e184655ef8c713aa79f9e23cb1f7df4,
since these syscalls are used elsewhere.

Change-Id: I5b5bf3d78edd137e820d25281a375966b6c009ec
armv6: REX routines are currently broken, use alternatives

Change-Id: I7ac05ab6add7802a4cc24fe36f7181e7cdfe07e0
libc: krait: Use performance version of memcpy.

Change-Id: I47d25d1da5b1a96bbc1b60f8acdaa31721a68e73
libc: krait: Use performance version of bcopy and memmove

Change-Id: I587085aeb0c30ceccaa3f420594a194b129632b5
libc: krait: Restore prior version of strcmp.

Change-Id: I8ddcdb4d3a905dd746985435dcdb525ab5a1c947
libc/arm: add cortex-a8 cpu variant

Change-Id: I30e8dd6d4b2e7889aea8f5ed21182a5941bfb489
Bionic/libm: fast neon pow() for small x,y.

Add a fast neon version of pow() suitable for relatively small
positive x and y (between 0 and 4).  Run the standard
implementation in all other cases.  Gives approximately 60%
performance improvement to AnTuTu FPU scores

Change-Id: I97e0712daeb2740764b26a44be0caaa39c481453
Bionic/libm: Prefer branches and VFP ABI.

For internal functions set gcc attribute "aapcs-vfp" for ARM
and use -fno-if-conversion to prefer branches over predicated
instructions (improves performance on architectures with good
branch prediction).

Change-Id: I8424e0e82a19d35e7e3b6e3e122dcdecdd5426fd
Bionic/libm: add assembly versions of sin/cos.

Add assembly versions of sin/cos with integrated remainder pi/2
calculation.  Directly extracted from binary libm.so compiled with
__ieee754_rem_pio2 calls inlined.

Change-Id: Ia093f420e58e794635e3a5f09e8236ae7601f1f6
Bionic/libm: Pow optimizations and bug fixes.

Use VFP calling convention for pow_neon handoff function by default.
Fix register usage collision between two different polynomial
coefficients in pow_neon.  Remove conditional execution in pow_neon
and replace with branching.

Change-Id: I76095f4a006e2fb01a53943b66fd69bfa1fd3033
Bionic/libm: Add precision-correct de-serialize sin/cos.

Modify sin/cos to improve performance while retaining bit-for-bit
accuracy with existing algorithm.

Change-Id: Iaba2dd731cd015732744705dad8bddb713b43067
libm: optimistic pow calling.

Call optimized pow optimistically and revert to full range
implementation if we detect an out-of-range input.

Change-Id: I6f3aa734adbf99484b7ff70736ef83a41e5815b8
libm: sqrt and sqrtf via ARM vsqrt instruction

Optimized sqrt and sqrtf for arm by using hardware
opcode for sqrt rather than generic slow portable
code.

Change-Id: I84694159577aef6418710548085d8149c45e0e3f
Bionic/libm: Remove extra vmov from sin/cos.

Move integer representations of x bits on the integer side rather
than moving them to and from the FP registers.

Change-Id: I1895db385c9616cdae9ab6403f392dfbae292adc
Bionic/libm: enable optimized math functions on more QCOM targets.

allow more QCOM targets to use optimized math functions.

Change-Id: I76ee1bf951ae1c8397fef3af6e9937ed8cad9b62
libm: Fix multiple inclusion warning

Change-Id: Ifa732ec52fb582c34512cd1d09d918199ae7395e