Fix compilation of base for arm64

Add support for the architecture to build/build_config.h (define
new macro ARCH_CPU_ARM64 to identify the CPU architecture and
set the other appropriate macros to 1).

Fix DEBUG_BREAK_ASM() macro to expand to the correct instruction
on arm64 cpu (as instruction set is not compatible with previous
version of ARM instruction sets).

BUG=339477
R=mark@chromium.org

Review URL: https://codereview.chromium.org/145273028

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@249246 0039d316-1c4b-4281-b951-d872f2087c98

base/debug/debugger_posix.cc

@@ -199,8 +199,10 @@ bool BeingDebugged() {
 //        SIGABRT
 // Mac: Always send SIGTRAP.
 
-#if defined(ARCH_CPU_ARM_FAMILY)
+#if defined(ARCH_CPU_ARMEL)
 #define DEBUG_BREAK_ASM() asm("bkpt 0")
+#elif defined(ARCH_CPU_ARM64)
+#define DEBUG_BREAK_ASM() asm("brk 0")
 #elif defined(ARCH_CPU_MIPS_FAMILY)
 #define DEBUG_BREAK_ASM() asm("break 2")
 #elif defined(ARCH_CPU_X86_FAMILY)

build/build_config.h

@@ -106,6 +106,11 @@
 #define ARCH_CPU_ARMEL 1
 #define ARCH_CPU_32_BITS 1
 #define ARCH_CPU_LITTLE_ENDIAN 1
+#elif defined(__arm64__)
+#define ARCH_CPU_ARM_FAMILY 1
+#define ARCH_CPU_ARM64 1
+#define ARCH_CPU_64_BITS 1
+#define ARCH_CPU_LITTLE_ENDIAN 1
 #elif defined(__pnacl__)
 #define ARCH_CPU_32_BITS 1
 #define ARCH_CPU_LITTLE_ENDIAN 1