[PATCH][AArch64] LINK_SPEC changes for Cortex-A53 erratum 835769 workaround

[Kyrill Tkachov <kyrylo dot tkachov at arm dot com>]

Hi all,

This patch contains the LINK_SPEC changes required to pass on the linker 
option --fix-cortex-a53-835769 when compiling with 
-mfix-cortex-a53-835769 (or by default when configured with 
--enable-fix-cortex-a53-835769).

This requires a binutils installation with the patch posted at 
https://sourceware.org/ml/binutils/2014-10/msg00198.html applied.


Bootstrapped and tested on aarch64-none-linux-gnu and built various 
benchmarks.
This patch applies to 4.9 (4.8 version will be posted separately) and 
has been tested there as well.

Ok for trunk and 4.9?

Thanks,
Kyrill



2014-10-22  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

    * config/aarch64/aarch64-elf-raw.h (CA53_ERR_835769_SPEC): Define.
    (LINK_SPEC): Include CA53_ERR_835769_SPEC.
    * config/aarch64/aarch64-linux.h (CA53_ERR_835769_SPEC): Define.
    (LINK_SPEC): Include CA53_ERR_835769_SPEC.

diff --git a/gcc/config/aarch64/aarch64-elf-raw.h b/gcc/config/aarch64/aarch64-elf-raw.h
index b9d4e8d..16ad5c8 100644
--- a/gcc/config/aarch64/aarch64-elf-raw.h
+++ b/gcc/config/aarch64/aarch64-elf-raw.h
@@ -27,9 +27,18 @@
   " crtend%O%s crtn%O%s " \
   "%{Ofast|ffast-math|funsafe-math-optimizations:crtfastmath.o%s}"
 
+#ifdef TARGET_FIX_ERR_A53_835769_DEFAULT
+#define CA53_ERR_835769_SPEC \
+  " %{!mno-fix-cortex-a53-835769:--fix-cortex-a53-835769}"
+#else
+#define CA53_ERR_835769_SPEC \
+  " %{mfix-cortex-a53-835769:--fix-cortex-a53-835769}"
+#endif
+
 #ifndef LINK_SPEC
 #define LINK_SPEC "%{mbig-endian:-EB} %{mlittle-endian:-EL} -X \
-  -maarch64elf%{mabi=ilp32*:32}%{mbig-endian:b}"
+  -maarch64elf%{mabi=ilp32*:32}%{mbig-endian:b}" \
+  CA53_ERR_835769_SPEC
 #endif
 
 #endif /* GCC_AARCH64_ELF_RAW_H */
diff --git a/gcc/config/aarch64/aarch64-linux.h b/gcc/config/aarch64/aarch64-linux.h
index 3fbde93..d375624 100644
--- a/gcc/config/aarch64/aarch64-linux.h
+++ b/gcc/config/aarch64/aarch64-linux.h
@@ -41,7 +41,16 @@
    %{mbig-endian:-EB} %{mlittle-endian:-EL}     \
    -maarch64linux%{mabi=ilp32:32}%{mbig-endian:b}"
 
-#define LINK_SPEC LINUX_TARGET_LINK_SPEC
+#ifdef TARGET_FIX_ERR_A53_835769_DEFAULT
+#define CA53_ERR_835769_SPEC \
+  " %{!mno-fix-cortex-a53-835769:--fix-cortex-a53-835769}"
+#else
+#define CA53_ERR_835769_SPEC \
+  " %{mfix-cortex-a53-835769:--fix-cortex-a53-835769}"
+#endif
+
+#define LINK_SPEC LINUX_TARGET_LINK_SPEC \
+                  CA53_ERR_835769_SPEC
 
 #define GNU_USER_TARGET_MATHFILE_SPEC \
   "%{Ofast|ffast-math|funsafe-math-optimizations:crtfastmath.o%s}"