3 files changed, 34 insertions, 2 deletions

diff --git a/src/lib_jit.c b/src/lib_jit.c
index 259a03e1..6e16d45b 100644
--- a/src/lib_jit.c
+++ b/src/lib_jit.c
@@ -520,6 +520,10 @@ JIT_PARAMDEF(JIT_PARAMINIT)
 };
 #endif
 
+#if LJ_TARGET_ARM && LJ_TARGET_LINUX
+#include <sys/utsname.h>
+#endif
+
 /* Arch-dependent CPU detection. */
 static uint32_t jit_cpudetect(lua_State *L)
 {
@@ -563,7 +567,27 @@ static uint32_t jit_cpudetect(lua_State *L)
 #endif
 #endif
 #elif LJ_TARGET_ARM
-  /* NYI */
+  /* Compile-time ARM CPU detection. */
+#if __ARM_ARCH_7__ || __ARM_ARCH_7A__ || __ARM_ARCH_7R__
+  flags |= JIT_F_ARMV6|JIT_F_ARMV6T2|JIT_F_ARMV7;
+#elif __ARM_ARCH_6T2__
+  flags |= JIT_F_ARMV6|JIT_F_ARMV6T2;
+#elif __ARM_ARCH_6__ || __ARM_ARCH_6J__ || __ARM_ARCH_6Z__ || __ARM_ARCH_6ZK__
+  flags |= JIT_F_ARMV6;
+#endif
+  /* Runtime ARM CPU detection. */
+#if LJ_TARGET_LINUX
+  if (!(flags & JIT_F_ARMV7)) {
+    struct utsname ut;
+    uname(&ut);
+    if (strncmp(ut.machine, "armv", 4) == 0) {
+      if (ut.machine[4] >= '7')
+        flags |= JIT_F_ARMV6|JIT_F_ARMV6T2|JIT_F_ARMV7;
+      else if (ut.machine[4] == '6')
+        flags |= JIT_F_ARMV6;
+    }
+  }
+#endif
 #elif LJ_TARGET_PPC
   /* Nothing to do. */
 #else
diff --git a/src/lj_def.h b/src/lj_def.h
index 86f041a4..197df291 100644
--- a/src/lj_def.h
+++ b/src/lj_def.h
@@ -136,7 +136,7 @@ static LJ_AINLINE uint32_t lj_bswap(uint32_t x)
 {
   uint32_t r;
 #if __ARM_ARCH_6__ || __ARM_ARCH_6J__ || __ARM_ARCH_6T2__ || __ARM_ARCH_6Z__ ||\
-    __ARM_ARCH_7__ || __ARM_ARCH_7A__ || __ARM_ARCH_7R__
+    __ARM_ARCH_6ZK__ || __ARM_ARCH_7__ || __ARM_ARCH_7A__ || __ARM_ARCH_7R__
   __asm__("rev %0, %1" : "=r" (r) : "r" (x));
   return r;
 #else
diff --git a/src/lj_jit.h b/src/lj_jit.h
index 63584355..ea2dd4ad 100644
--- a/src/lj_jit.h
+++ b/src/lj_jit.h
@@ -26,6 +26,14 @@
 /* Names for the CPU-specific flags. Must match the order above. */
 #define JIT_F_CPU_FIRST         JIT_F_CMOV
 #define JIT_F_CPUSTRING         "\4CMOV\4SSE2\4SSE3\6SSE4.1\2P4\3AMD\2K8\4ATOM"
+#elif LJ_TARGET_ARM
+#define JIT_F_ARMV6             0x00000010
+#define JIT_F_ARMV6T2           0x00000020
+#define JIT_F_ARMV7             0x00000040
+
+/* Names for the CPU-specific flags. Must match the order above. */
+#define JIT_F_CPU_FIRST         JIT_F_ARMV6
+#define JIT_F_CPUSTRING         "\5ARMv6\7ARMv6T2\5ARMv7"
 #else
 #define JIT_F_CPU_FIRST         0
 #define JIT_F_CPUSTRING         ""