aarch64: Add support for Go closures

diff --git a/src/aarch64/ffi.c b/src/aarch64/ffi.c
index f546ab2..0cace9d 100644 (file)
--- a/src/aarch64/ffi.c
+++ b/src/aarch64/ffi.c
@@ -539,13 +539,14 @@ ffi_status ffi_prep_cif_machdep_var(ffi_cif *cif,
 #endif /* __APPLE__ */
 
 extern void ffi_call_SYSV (struct call_context *context, void *frame,
-                          void (*fn)(void), void *rvalue, int flags)
-       FFI_HIDDEN;
+                          void (*fn)(void), void *rvalue, int flags,
+                          void *closure) FFI_HIDDEN;
 
 /* Call a function with the provided arguments and capture the return
    value.  */
-void
-ffi_call (ffi_cif *cif, void (*fn)(void), void *orig_rvalue, void **avalue)
+static void
+ffi_call_int (ffi_cif *cif, void (*fn)(void), void *orig_rvalue,
+             void **avalue, void *closure)
 {
   struct call_context *context;
   void *stack, *frame, *rvalue;
@@ -698,12 +699,27 @@ ffi_call (ffi_cif *cif, void (*fn)(void), void *orig_rvalue, void **avalue)
 #endif
     }
 
-  ffi_call_SYSV (context, frame, fn, rvalue, flags);
+  ffi_call_SYSV (context, frame, fn, rvalue, flags, closure);
 
   if (flags & AARCH64_RET_NEED_COPY)
     memcpy (orig_rvalue, rvalue, rtype_size);
 }
 
+void
+ffi_call (ffi_cif *cif, void (*fn) (void), void *rvalue, void **avalue)
+{
+  ffi_call_int (cif, fn, rvalue, avalue, NULL);
+}
+
+#ifdef FFI_GO_CLOSURES
+void
+ffi_call_go (ffi_cif *cif, void (*fn) (void), void *rvalue,
+            void **avalue, void *closure)
+{
+  ffi_call_int (cif, fn, rvalue, avalue, closure);
+}
+#endif /* FFI_GO_CLOSURES */
+
 /* Build a trampoline.  */
 
 extern void ffi_closure_SYSV (void) FFI_HIDDEN;
@@ -744,6 +760,32 @@ ffi_prep_closure_loc (ffi_closure *closure,
   return FFI_OK;
 }
 
+#ifdef FFI_GO_CLOSURES
+extern void ffi_go_closure_SYSV (void) FFI_HIDDEN;
+extern void ffi_go_closure_SYSV_V (void) FFI_HIDDEN;
+
+ffi_status
+ffi_prep_go_closure (ffi_go_closure *closure, ffi_cif* cif,
+                     void (*fun)(ffi_cif*,void*,void**,void*))
+{
+  void (*start)(void);
+
+  if (cif->abi != FFI_SYSV)
+    return FFI_BAD_ABI;
+
+  if (cif->flags & AARCH64_FLAG_ARG_V)
+    start = ffi_go_closure_SYSV_V;
+  else
+    start = ffi_go_closure_SYSV;
+
+  closure->tramp = start;
+  closure->cif = cif;
+  closure->fun = fun;
+
+  return FFI_OK;
+}
+#endif /* FFI_GO_CLOSURES */
+
 /* Primary handler to setup and invoke a function within a closure.
 
    A closure when invoked enters via the assembler wrapper

diff --git a/src/aarch64/ffitarget.h b/src/aarch64/ffitarget.h
index 7461386..80d09af 100644 (file)
--- a/src/aarch64/ffitarget.h
+++ b/src/aarch64/ffitarget.h
@@ -50,6 +50,10 @@ typedef enum ffi_abi
 #if defined (__APPLE__)
 #define FFI_TARGET_SPECIFIC_VARIADIC
 #define FFI_EXTRA_CIF_FIELDS unsigned aarch64_nfixedargs
+#else
+/* iOS reserves x18 for the system.  Disable Go closures until
+   a new static chain is chosen.  */
+#define FFI_GO_CLOSURES 1
 #endif
 
 #define FFI_TARGET_HAS_COMPLEX_TYPE

diff --git a/src/aarch64/sysv.S b/src/aarch64/sysv.S
index 7f00a3f..1fb68f2 100644 (file)
--- a/src/aarch64/sysv.S
+++ b/src/aarch64/sysv.S
@@ -50,7 +50,8 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
 
 /* ffi_call_SYSV
    extern void ffi_call_SYSV (void *stack, void *frame,
-                             void (*fn)(void), void *rvalue, int flags);
+                             void (*fn)(void), void *rvalue,
+                             int flags, void *closure);
 
    Therefore on entry we have:
 
@@ -59,6 +60,7 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
    x2 fn
    x3 rvalue
    x4 flags
+   x5 closure
 */
 
        cfi_startproc
@@ -74,6 +76,9 @@ CNAME(ffi_call_SYSV):
 
        mov     x9, x2                  /* save fn */
        mov     x8, x3                  /* install structure return */
+#ifdef FFI_GO_CLOSURES
+       mov     x18, x5                 /* install static chain */
+#endif
        stp     x3, x4, [x29, #16]      /* save rvalue and flags */
 
        /* Load the vector argument passing registers, if necessary.  */
@@ -245,6 +250,7 @@ CNAME(ffi_closure_SYSV):
        /* Load ffi_closure_inner arguments.  */
        ldp     x0, x1, [x17, #FFI_TRAMPOLINE_SIZE]     /* load cif, fn */
        ldr     x2, [x17, #FFI_TRAMPOLINE_SIZE+16]      /* load user_data */
+.Ldo_closure:
        add     x3, sp, #16                             /* load context */
        add     x4, sp, #ffi_closure_SYSV_FS            /* load stack */
        add     x5, sp, #16+CALL_CONTEXT_SIZE           /* load rvalue */
@@ -336,3 +342,57 @@ CNAME(ffi_closure_SYSV):
        .hidden CNAME(ffi_closure_SYSV)
        .size   CNAME(ffi_closure_SYSV), . - CNAME(ffi_closure_SYSV)
 #endif
+
+#ifdef FFI_GO_CLOSURES
+       .align 4
+CNAME(ffi_go_closure_SYSV_V):
+       cfi_startproc
+       stp     x29, x30, [sp, #-ffi_closure_SYSV_FS]!
+       cfi_adjust_cfa_offset (ffi_closure_SYSV_FS)
+       cfi_rel_offset (x29, 0)
+       cfi_rel_offset (x30, 8)
+
+       /* Save the argument passing vector registers.  */
+       stp     q0, q1, [sp, #16 + 0]
+       stp     q2, q3, [sp, #16 + 32]
+       stp     q4, q5, [sp, #16 + 64]
+       stp     q6, q7, [sp, #16 + 96]
+       b       0f
+       cfi_endproc
+
+       .globl  CNAME(ffi_go_closure_SYSV_V)
+#ifdef __ELF__
+       .type   CNAME(ffi_go_closure_SYSV_V), #function
+       .hidden CNAME(ffi_go_closure_SYSV_V)
+       .size   CNAME(ffi_go_closure_SYSV_V), . - CNAME(ffi_go_closure_SYSV_V)
+#endif
+
+       .align  4
+       cfi_startproc
+CNAME(ffi_go_closure_SYSV):
+       stp     x29, x30, [sp, #-ffi_closure_SYSV_FS]!
+       cfi_adjust_cfa_offset (ffi_closure_SYSV_FS)
+       cfi_rel_offset (x29, 0)
+       cfi_rel_offset (x30, 8)
+0:
+       mov     x29, sp
+
+       /* Save the argument passing core registers.  */
+       stp     x0, x1, [sp, #16 + 16*N_V_ARG_REG + 0]
+       stp     x2, x3, [sp, #16 + 16*N_V_ARG_REG + 16]
+       stp     x4, x5, [sp, #16 + 16*N_V_ARG_REG + 32]
+       stp     x6, x7, [sp, #16 + 16*N_V_ARG_REG + 48]
+
+       /* Load ffi_closure_inner arguments.  */
+       ldp     x0, x1, [x18, #8]                       /* load cif, fn */
+       mov     x2, x18                                 /* load user_data */
+       b       .Ldo_closure
+       cfi_endproc
+
+       .globl  CNAME(ffi_go_closure_SYSV)
+#ifdef __ELF__
+       .type   CNAME(ffi_go_closure_SYSV), #function
+       .hidden CNAME(ffi_go_closure_SYSV)
+       .size   CNAME(ffi_go_closure_SYSV), . - CNAME(ffi_go_closure_SYSV)
+#endif
+#endif /* FFI_GO_CLOSURES */