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PUBLIC ffi_call_AMD64
EXTRN __chkstk:NEAR
EXTRN ffi_closure_SYSV:NEAR
_TEXT SEGMENT
;;; ffi_closure_OUTER will be called with these registers set:
;;; rax points to 'closure'
;;; r11 contains a bit mask that specifies which of the
;;; first four parameters are float or double
;;;
;;; It must move the parameters passed in registers to their stack location,
;;; call ffi_closure_SYSV for the actual work, then return the result.
;;;
ffi_closure_OUTER PROC FRAME
;; save actual arguments to their stack space.
test r11, 1
jne first_is_float
mov QWORD PTR [rsp+8], rcx
jmp second
first_is_float:
movlpd QWORD PTR [rsp+8], xmm0
second:
test r11, 2
jne second_is_float
mov QWORD PTR [rsp+16], rdx
jmp third
second_is_float:
movlpd QWORD PTR [rsp+16], xmm1
third:
test r11, 4
jne third_is_float
mov QWORD PTR [rsp+24], r8
jmp forth
third_is_float:
movlpd QWORD PTR [rsp+24], xmm2
forth:
test r11, 8
jne forth_is_float
mov QWORD PTR [rsp+32], r9
jmp done
forth_is_float:
movlpd QWORD PTR [rsp+32], xmm3
done:
.ALLOCSTACK 40
sub rsp, 40
.ENDPROLOG
mov rcx, rax ; context is first parameter
mov rdx, rsp ; stack is second parameter
add rdx, 40 ; correct our own area
mov rax, ffi_closure_SYSV
call rax ; call the real closure function
;; Here, code is missing that handles float return values
add rsp, 40
movd xmm0, rax ; In case the closure returned a float.
ret 0
ffi_closure_OUTER ENDP
;;; ffi_call_AMD64
stack$ = 0
prepfunc$ = 32
ecif$ = 40
bytes$ = 48
flags$ = 56
rvalue$ = 64
fn$ = 72
ffi_call_AMD64 PROC FRAME
mov QWORD PTR [rsp+32], r9
mov QWORD PTR [rsp+24], r8
mov QWORD PTR [rsp+16], rdx
mov QWORD PTR [rsp+8], rcx
.PUSHREG rbp
push rbp
.ALLOCSTACK 48
sub rsp, 48 ; 00000030H
.SETFRAME rbp, 32
lea rbp, QWORD PTR [rsp+32]
.ENDPROLOG
mov eax, DWORD PTR bytes$[rbp]
add rax, 15
and rax, -16
call __chkstk
sub rsp, rax
lea rax, QWORD PTR [rsp+32]
mov QWORD PTR stack$[rbp], rax
mov rdx, QWORD PTR ecif$[rbp]
mov rcx, QWORD PTR stack$[rbp]
call QWORD PTR prepfunc$[rbp]
mov rsp, QWORD PTR stack$[rbp]
movlpd xmm3, QWORD PTR [rsp+24]
movd r9, xmm3
movlpd xmm2, QWORD PTR [rsp+16]
movd r8, xmm2
movlpd xmm1, QWORD PTR [rsp+8]
movd rdx, xmm1
movlpd xmm0, QWORD PTR [rsp]
movd rcx, xmm0
call QWORD PTR fn$[rbp]
ret_int$:
cmp DWORD PTR flags$[rbp], 1 ; FFI_TYPE_INT
jne ret_float$
mov rcx, QWORD PTR rvalue$[rbp]
mov DWORD PTR [rcx], eax
jmp SHORT ret_nothing$
ret_float$:
cmp DWORD PTR flags$[rbp], 2 ; FFI_TYPE_FLOAT
jne SHORT ret_double$
mov rax, QWORD PTR rvalue$[rbp]
movlpd QWORD PTR [rax], xmm0
jmp SHORT ret_nothing$
ret_double$:
cmp DWORD PTR flags$[rbp], 3 ; FFI_TYPE_DOUBLE
jne SHORT ret_int64$
mov rax, QWORD PTR rvalue$[rbp]
movlpd QWORD PTR [rax], xmm0
jmp SHORT ret_nothing$
ret_int64$:
cmp DWORD PTR flags$[rbp], 12 ; FFI_TYPE_SINT64
jne ret_nothing$
mov rcx, QWORD PTR rvalue$[rbp]
mov QWORD PTR [rcx], rax
jmp SHORT ret_nothing$
ret_nothing$:
xor eax, eax
lea rsp, QWORD PTR [rbp+16]
pop rbp
ret 0
ffi_call_AMD64 ENDP
_TEXT ENDS
END
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