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diff --git a/ext/ffi_c/libffi/src/nios2/sysv.S b/ext/ffi_c/libffi/src/nios2/sysv.S
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+/* Low-level libffi support for Altera Nios II.
+
+ Copyright (c) 2013 Mentor Graphics.
+
+ Permission is hereby granted, free of charge, to any person obtaining
+ a copy of this software and associated documentation files (the
+ ``Software''), to deal in the Software without restriction, including
+ without limitation the rights to use, copy, modify, merge, publish,
+ distribute, sublicense, and/or sell copies of the Software, and to
+ permit persons to whom the Software is furnished to do so, subject to
+ the following conditions:
+
+ The above copyright notice and this permission notice shall be
+ included in all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
+ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
+
+/* This function is declared on the C side as
+
+ extern UINT64 ffi_call_sysv (void (*arghook) (char *, extended_cif *),
+ extended_cif *ecif,
+ unsigned nbytes,
+ void (*fn) (void));
+
+ On input, the arguments appear as
+ r4 = arghook
+ r5 = ecif
+ r6 = nbytes
+ r7 = fn
+*/
+
+ .section .text
+ .align 2
+ .global ffi_call_sysv
+ .type ffi_call_sysv, @function
+
+ffi_call_sysv:
+ .cfi_startproc
+
+ /* Create the stack frame, saving r16 so we can use it locally. */
+ addi sp, sp, -12
+ .cfi_def_cfa_offset 12
+ stw ra, 8(sp)
+ stw fp, 4(sp)
+ stw r16, 0(sp)
+ .cfi_offset 31, -4
+ .cfi_offset 28, -8
+ .cfi_offset 16, -12
+ mov fp, sp
+ .cfi_def_cfa_register 28
+ mov r16, r7
+
+ /* Adjust the stack pointer to create the argument buffer
+ nbytes long. */
+ sub sp, sp, r6
+
+ /* Call the arghook function. */
+ mov r2, r4 /* fn */
+ mov r4, sp /* argbuffer */
+ callr r2 /* r5 already contains ecif */
+
+ /* Pop off the first 16 bytes of the argument buffer on the stack,
+ transferring the contents to the argument registers. */
+ ldw r4, 0(sp)
+ ldw r5, 4(sp)
+ ldw r6, 8(sp)
+ ldw r7, 12(sp)
+ addi sp, sp, 16
+
+ /* Call the user function, which leaves its result in r2 and r3. */
+ callr r16
+
+ /* Pop off the stack frame. */
+ mov sp, fp
+ ldw ra, 8(sp)
+ ldw fp, 4(sp)
+ ldw r16, 0(sp)
+ addi sp, sp, 12
+ ret
+ .cfi_endproc
+ .size ffi_call_sysv, .-ffi_call_sysv
+
+
+/* Closure trampolines jump here after putting the C helper address
+ in r9 and the closure pointer in r10. The user-supplied arguments
+ to the closure are in the normal places, in r4-r7 and on the
+ stack. Push the register arguments on the stack too and then call the
+ C helper function to deal with them. */
+
+ .section .text
+ .align 2
+ .global ffi_closure_sysv
+ .type ffi_closure_sysv, @function
+
+ffi_closure_sysv:
+ .cfi_startproc
+
+ /* Create the stack frame, pushing the register args on the stack
+ just below the stack args. This is the same trick illustrated
+ in Figure 7-3 in the Nios II Processor Reference Handbook, used
+ for variable arguments and structures passed by value. */
+ addi sp, sp, -20
+ .cfi_def_cfa_offset 20
+ stw ra, 0(sp)
+ .cfi_offset 31, -20
+ stw r4, 4(sp)
+ .cfi_offset 4, -16
+ stw r5, 8(sp)
+ .cfi_offset 5, -12
+ stw r6, 12(sp)
+ .cfi_offset 6, -8
+ stw r7, 16(sp)
+ .cfi_offset 7, -4
+
+ /* Call the helper.
+ r4 = pointer to arguments on stack
+ r5 = closure pointer (loaded in r10 by the trampoline)
+ r9 = address of helper function (loaded by trampoline) */
+ addi r4, sp, 4
+ mov r5, r10
+ callr r9
+
+ /* Pop the stack and return. */
+ ldw ra, 0(sp)
+ addi sp, sp, 20
+ .cfi_def_cfa_offset -20
+ ret
+ .cfi_endproc
+ .size ffi_closure_sysv, .-ffi_closure_sysv
+