In patch b219285f87 you have a syntax
error in the PLD instruction. The syntax for the pld argument should be
in square brackets as it's a memory address like so: pld [r1]. With
your patch the newlib build fails for armv7-a targets. This patch fixes
the build failures.
Tested by making sure the newlib build completes successfully.
2016-01-26 Kyrylo Tkachov <kyrylo.tkachov@arm.com>
* libc/machine/arm/strcpy.c (strcpy): Fix PLD assembly syntax.
* libc/machine/arm/strlen-stub.c (strlen): Likewise.
LTO can re-order top-level assembly blocks, which can cause this
macro definition to appear after its use (or not at all), causing
compilation failures. On modern toolchains (armv4t+), assembly
should write `bx lr` in all cases, and linkers will transparently
convert them to `mov pc, lr`, allowing us to simply remove the
macro.
(source: https://groups.google.com/forum/#!topic/comp.sys.arm/3l7fVGX-Wug
and verified empirically)
For the armv4.S file, preserve this macro to maximize backwards
compatibility.
LTO can re-order top-level assembly blocks, which can cause this
macro definition to appear after its use (or not at all), causing
compilation failures. As the macro has very few uses, simply removing
it by inlining is a simple fix.
n.b. one of the macro invocations in strlen-stub.c was already
guarded by the relevant #define, so it is simply converted directly
to a pld
2016-04-18 Thomas Preud'homme <thomas.preudhomme@arm.com>
* libc/machine/arm/strlen-stub.c: Check capabilities of architecture
to decide which Thumb implementation to use and fall back to C
implementation for architecture not supporting Thumb mode.
* libc/machine/arm/strlen.S: Likewise.
Reformulate the strcmp-armv7.S selection logic around the architecture
features required by the implementation code rather (some) version of
the architecture that expose those features.
The patch moves the inline ASM thumb2 -Os implementation out into its
own .S file.
Tested by building newlib and comparing libc.a binaries before and
after for all permutations of:
Architectures:
armv4 armv4t armv5 armv5t armv5te armv6 armv6j armv6k
armv6z armv6kz armv6t2 armv6-m armv6s-m armv7 armv7-a
armv7ve armv7-r armv7-m armv7e-m armv8-a iwmmxt iwmmxt2
ISAs:
thumb arm
Optimization Levels:
Os O2
Excluding:
armv6s-m -mthumb
armv6-m -mthumb
armv6zk -mthumb
armv6z -mthumb
armv6k -mthumb
armv6j -mthumb
The patch moves the inline ASM thumb1 -O2 implementation out into its
own .S file.
Tested by building newlib and comparing libc.a binaries before and
after for all permutations of:
Architectures:
armv4 armv4t armv5 armv5t armv5te armv6 armv6j armv6k
armv6z armv6kz armv6t2 armv6-m armv6s-m armv7 armv7-a
armv7ve armv7-r armv7-m armv7e-m armv8-a iwmmxt iwmmxt2
ISAs:
thumb arm
Optimization Levels:
Os O2
Excluding:
armv6s-m -mthumb
armv6-m -mthumb
armv6zk -mthumb
armv6z -mthumb
armv6k -mthumb
armv6j -mthumb
The patch adds strlen.S to contain the complementary preprocessor
logic to strlen-stub.c intended to provide #inclusion of alternative
.S implementations.
Initially we just include the existing strlen-armv7.S implementation.
We rewrite _ISA_ARMV7 in both strlen.S and strlen-stub.c to use the
underlying existing underlying defintion from arm_asm.h in order to
avoide including that file, this is in effect the first step towards a
move to ACLE predefines only.
Tested by building newlib and comparing libc.a binaries before and
after for all permutations of:
Architectures:
armv4 armv4t armv5 armv5t armv5te armv6 armv6j armv6k
armv6z armv6kz armv6t2 armv6-m armv6s-m armv7 armv7-a
armv7ve armv7-r armv7-m armv7e-m armv8-a iwmmxt iwmmxt2
ISAs:
thumb arm
Optimization Levels:
Os O2
Excluding:
armv6s-m -mthumb
armv6-m -mthumb
armv6zk -mthumb
armv6z -mthumb
armv6k -mthumb
armv6j -mthumb
In order to maintain consistency both within machine/arm and between
machine/arm and machine/aarch64, rename the 'c' stub to -stub.c.
Tested by building newlib and comparing libc.a binaries before and
after for all permutations of:
Architectures:
armv4 armv4t armv5 armv5t armv5te armv6 armv6j armv6k
armv6z armv6kz armv6t2 armv6-m armv6s-m armv7 armv7-a
armv7ve armv7-r armv7-m armv7e-m armv8-a iwmmxt iwmmxt2
ISAs:
thumb arm
Optimization Levels:
Os O2
Excluding:
armv6s-m -mthumb
armv6-m -mthumb
armv6zk -mthumb
armv6z -mthumb
armv6k -mthumb
armv6j -mthumb
Kyrill Tkachov
Pat Pannuto
Jeff Johnston
Marcus Shawcroft