From e102347ae923f983ae5e19281ba4c93fb17dc6ca Mon Sep 17 00:00:00 2001
From: Elijah Taylor <elijahtaylor@google.com>
Date: Thu, 31 Jan 2013 14:00:58 -0800
Subject: [PATCH] NaCl/arm initial support (Apply part of commit 21f0df7 from
 'mono_libgc' branch.)

Conflicts:
* include/private/gc_locks.h
* include/private/gcconfig.h
* pthread_stop_world.c
---
 include/private/gcconfig.h           | 12 +++++++++---
 include/private/pthread_stop_world.h |  7 ++++++-
 pthread_stop_world.c                 | 16 +++++++++++++++-
 3 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/include/private/gcconfig.h b/include/private/gcconfig.h
index 2f80b3d0..e2dcc864 100644
--- a/include/private/gcconfig.h
+++ b/include/private/gcconfig.h
@@ -93,7 +93,7 @@
 /* Determine the machine type: */
 # if defined(__native_client__)
 #    define NACL
-#    if !defined(__portable_native_client__)
+#    if !defined(__portable_native_client__) && !defined(__arm__)
 #      define I386
 #      define mach_type_known
 #    else
@@ -109,7 +109,9 @@
 # endif
 # if defined(__arm) || defined(__arm__) || defined(__thumb__)
 #    define ARM32
-#    if !defined(LINUX) && !defined(NETBSD) && !defined(FREEBSD) \
+#    if defined(NACL)
+#      define mach_type_known
+#    elif !defined(LINUX) && !defined(NETBSD) && !defined(FREEBSD) \
         && !defined(OPENBSD) && !defined(DARWIN) \
         && !defined(_WIN32) && !defined(__CEGCC__) && !defined(SYMBIAN)
 #      define NOSYS
@@ -2134,8 +2136,12 @@
 # endif
 
 # ifdef ARM32
+#   if defined(NACL)
+#     define MACH_TYPE "NACL"
+#   else
+#     define MACH_TYPE "ARM32"
+#   endif
 #   define CPP_WORDSZ 32
-#   define MACH_TYPE "ARM32"
 #   define ALIGNMENT 4
 #   ifdef NETBSD
 #       define OS_TYPE "NETBSD"
diff --git a/include/private/pthread_stop_world.h b/include/private/pthread_stop_world.h
index 48374286..49b87bc6 100644
--- a/include/private/pthread_stop_world.h
+++ b/include/private/pthread_stop_world.h
@@ -34,7 +34,12 @@ struct thread_stop_info {
       /* saved registers, they may be pushed to the stack much earlier. */
       /* Also, on amd64 'push' puts 8 bytes on the stack even though    */
       /* our pointers are 4 bytes.                                      */
-#     define NACL_GC_REG_STORAGE_SIZE 20
+#     ifdef ARM32
+        /* Space for r4-r8, r10-r12, r14.       */
+#       define NACL_GC_REG_STORAGE_SIZE 9
+#     else
+#       define NACL_GC_REG_STORAGE_SIZE 20
+#     endif
       ptr_t reg_storage[NACL_GC_REG_STORAGE_SIZE];
 #   endif
 };
diff --git a/pthread_stop_world.c b/pthread_stop_world.c
index c0bc2a5e..22393092 100644
--- a/pthread_stop_world.c
+++ b/pthread_stop_world.c
@@ -711,8 +711,22 @@ GC_INNER void GC_stop_world(void)
                 NACL_GC_REG_STORAGE_SIZE * sizeof(ptr_t));\
           __asm__ __volatile__ ("add $16, %esp"); \
         } while (0)
+# elif defined(__arm__)
+#   define NACL_STORE_REGS() \
+        do { \
+          __asm__ __volatile__ ("push {r4-r8,r10-r12,lr}"); \
+          __asm__ __volatile__ ("mov r0, %0" \
+                : : "r" (&GC_nacl_gc_thread_self->stop_info.stack_ptr)); \
+          __asm__ __volatile__ ("bic r0, r0, #0xc0000000"); \
+          __asm__ __volatile__ ("str sp, [r0]"); \
+          BCOPY(GC_nacl_gc_thread_self->stop_info.stack_ptr, \
+                GC_nacl_gc_thread_self->stop_info.reg_storage, \
+                NACL_GC_REG_STORAGE_SIZE * sizeof(ptr_t)); \
+          __asm__ __volatile__ ("add sp, sp, #40"); \
+          __asm__ __volatile__ ("bic sp, sp, #0xc0000000"); \
+        } while (0)
 # else
-#   error FIXME for non-amd64/x86 NaCl
+#   error TODO Please port NACL_STORE_REGS
 # endif
 
   GC_API_OSCALL void nacl_pre_syscall_hook(void)
-- 
2.40.0