-----------------------------------------------------------------------
n32.S - Copyright (c) 1996, 1998, 2005, 2007, 2009, 2010  Red Hat, Inc.

MIPS Foreign Function Interface 

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.
-----------------------------------------------------------------------

define LIBFFI_ASM

include <fficonfig.h> include <ffi.h>

Only build this code if we are compiling for n32

if defined(FFI_MIPS_N32)

define callback a0 define bytes a2 define flags a3 define raddr a4 define fn a5

define SIZEOF_FRAME ( 8 * FFI_SIZEOF_ARG )

ifdef __GNUC__

.abicalls

endif

.text
.align  2
.globl  ffi_call_N32
.ent    ffi_call_N32

ffi_call_N32:

.LFB3:

.frame  $fp, SIZEOF_FRAME, ra
.mask   0xc0000000,-FFI_SIZEOF_ARG
.fmask  0x00000000,0

# Prologue
SUBU    $sp, SIZEOF_FRAME                       # Frame size

.LCFI0:

REG_S   $fp, SIZEOF_FRAME - 2*FFI_SIZEOF_ARG($sp)       # Save frame pointer
REG_S   ra, SIZEOF_FRAME - 1*FFI_SIZEOF_ARG($sp)        # Save return address

.LCFI1:

move    $fp, $sp

.LCFI3:

move    t9, callback    # callback function pointer
REG_S   bytes, 2*FFI_SIZEOF_ARG($fp) # bytes
REG_S   flags, 3*FFI_SIZEOF_ARG($fp) # flags
REG_S   raddr, 4*FFI_SIZEOF_ARG($fp) # raddr
REG_S   fn,    5*FFI_SIZEOF_ARG($fp) # fn

# Allocate at least 4 words in the argstack
move    v0, bytes
bge     bytes, 4 * FFI_SIZEOF_ARG, bigger       
LI      v0, 4 * FFI_SIZEOF_ARG
b       sixteen

bigger: 
ADDU    t4, v0, 2 * FFI_SIZEOF_ARG -1   # make sure it is aligned 
and     v0, t4, -2 * FFI_SIZEOF_ARG             # to a proper boundry.

sixteen:

SUBU    $sp, $sp, v0    # move the stack pointer to reflect the
                        # arg space

move    a0, $sp         # 4 * FFI_SIZEOF_ARG
ADDU    a3, $fp, 3 * FFI_SIZEOF_ARG

# Call ffi_prep_args
jal     t9

# Copy the stack pointer to t9
move    t9, $sp

# Fix the stack if there are more than 8 64bit slots worth
# of arguments.

# Load the number of bytes
REG_L   t6, 2*FFI_SIZEOF_ARG($fp)

# Is it bigger than 8 * FFI_SIZEOF_ARG?
daddiu  t8, t6, -(8 * FFI_SIZEOF_ARG)
bltz    t8, loadregs

ADDU    t9, t9, t8

loadregs:

REG_L   t6, 3*FFI_SIZEOF_ARG($fp)  # load the flags word into t6.

and     t4, t6, ((1<<FFI_FLAG_BITS)-1)
bnez    t4, arg1_floatp
REG_L   a0, 0*FFI_SIZEOF_ARG(t9)
b       arg1_next

arg1_floatp:

bne     t4, FFI_TYPE_FLOAT, arg1_doublep
l.s     $f12, 0*FFI_SIZEOF_ARG(t9)
b       arg1_next

arg1_doublep:

l.d     $f12, 0*FFI_SIZEOF_ARG(t9)

arg1_next:

SRL     t4, t6, 1*FFI_FLAG_BITS
and     t4, ((1<<FFI_FLAG_BITS)-1)
bnez    t4, arg2_floatp
REG_L   a1, 1*FFI_SIZEOF_ARG(t9)
b       arg2_next

arg2_floatp:

bne     t4, FFI_TYPE_FLOAT, arg2_doublep
l.s     $f13, 1*FFI_SIZEOF_ARG(t9)      
b       arg2_next

arg2_doublep:

l.d     $f13, 1*FFI_SIZEOF_ARG(t9)

arg2_next:

SRL     t4, t6, 2*FFI_FLAG_BITS
and     t4, ((1<<FFI_FLAG_BITS)-1)
bnez    t4, arg3_floatp
REG_L   a2, 2*FFI_SIZEOF_ARG(t9)
b       arg3_next

arg3_floatp:

bne     t4, FFI_TYPE_FLOAT, arg3_doublep
l.s     $f14, 2*FFI_SIZEOF_ARG(t9)      
b       arg3_next

arg3_doublep:

l.d     $f14, 2*FFI_SIZEOF_ARG(t9)

arg3_next:

SRL     t4, t6, 3*FFI_FLAG_BITS
and     t4, ((1<<FFI_FLAG_BITS)-1)
bnez    t4, arg4_floatp
REG_L   a3, 3*FFI_SIZEOF_ARG(t9)
b       arg4_next

arg4_floatp:

bne     t4, FFI_TYPE_FLOAT, arg4_doublep
l.s     $f15, 3*FFI_SIZEOF_ARG(t9)      
b       arg4_next

arg4_doublep:

l.d     $f15, 3*FFI_SIZEOF_ARG(t9)

arg4_next:

SRL     t4, t6, 4*FFI_FLAG_BITS
and     t4, ((1<<FFI_FLAG_BITS)-1)
bnez    t4, arg5_floatp
REG_L   a4, 4*FFI_SIZEOF_ARG(t9)
b       arg5_next

arg5_floatp:

bne     t4, FFI_TYPE_FLOAT, arg5_doublep
l.s     $f16, 4*FFI_SIZEOF_ARG(t9)      
b       arg5_next

arg5_doublep:

l.d     $f16, 4*FFI_SIZEOF_ARG(t9)

arg5_next:

SRL     t4, t6, 5*FFI_FLAG_BITS
and     t4, ((1<<FFI_FLAG_BITS)-1)
bnez    t4, arg6_floatp
REG_L   a5, 5*FFI_SIZEOF_ARG(t9)
b       arg6_next

arg6_floatp:

bne     t4, FFI_TYPE_FLOAT, arg6_doublep
l.s     $f17, 5*FFI_SIZEOF_ARG(t9)      
b       arg6_next

arg6_doublep:

l.d     $f17, 5*FFI_SIZEOF_ARG(t9)

arg6_next:

SRL     t4, t6, 6*FFI_FLAG_BITS
and     t4, ((1<<FFI_FLAG_BITS)-1)
bnez    t4, arg7_floatp
REG_L   a6, 6*FFI_SIZEOF_ARG(t9)
b       arg7_next

arg7_floatp:

bne     t4, FFI_TYPE_FLOAT, arg7_doublep
l.s     $f18, 6*FFI_SIZEOF_ARG(t9)      
b       arg7_next

arg7_doublep:

l.d     $f18, 6*FFI_SIZEOF_ARG(t9)

arg7_next:

SRL     t4, t6, 7*FFI_FLAG_BITS
and     t4, ((1<<FFI_FLAG_BITS)-1)
bnez    t4, arg8_floatp
REG_L   a7, 7*FFI_SIZEOF_ARG(t9)
b       arg8_next

arg8_floatp:

bne     t4, FFI_TYPE_FLOAT, arg8_doublep
l.s     $f19, 7*FFI_SIZEOF_ARG(t9)      
b       arg8_next

arg8_doublep:

l.d     $f19, 7*FFI_SIZEOF_ARG(t9)

arg8_next:

callit:

# Load the function pointer
REG_L   t9, 5*FFI_SIZEOF_ARG($fp)

# If the return value pointer is NULL, assume no return value.
REG_L   t5, 4*FFI_SIZEOF_ARG($fp)
beqz    t5, noretval

# Shift the return type flag over
SRL     t6, 8*FFI_FLAG_BITS

beq     t6, FFI_TYPE_SINT32, retint     
bne     t6, FFI_TYPE_INT, retfloat

retint:

jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
REG_S   v0, 0(t4)
b       epilogue

retfloat:

bne     t6, FFI_TYPE_FLOAT, retdouble
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
s.s     $f0, 0(t4)
b       epilogue

retdouble:

bne     t6, FFI_TYPE_DOUBLE, retstruct_d
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
s.d     $f0, 0(t4)
b       epilogue

retstruct_d:

bne     t6, FFI_TYPE_STRUCT_D, retstruct_f
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
s.d     $f0, 0(t4)
b       epilogue

retstruct_f:

bne     t6, FFI_TYPE_STRUCT_F, retstruct_d_d
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
s.s     $f0, 0(t4)
b       epilogue

retstruct_d_d:

bne     t6, FFI_TYPE_STRUCT_DD, retstruct_f_f
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
s.d     $f0, 0(t4)
s.d     $f2, 8(t4)
b       epilogue

retstruct_f_f:

bne     t6, FFI_TYPE_STRUCT_FF, retstruct_d_f
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
s.s     $f0, 0(t4)
s.s     $f2, 4(t4)
b       epilogue

retstruct_d_f:

bne     t6, FFI_TYPE_STRUCT_DF, retstruct_f_d
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
s.d     $f0, 0(t4)
s.s     $f2, 8(t4)
b       epilogue

retstruct_f_d:

bne     t6, FFI_TYPE_STRUCT_FD, retstruct_d_soft
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
s.s     $f0, 0(t4)
s.d     $f2, 8(t4)
b       epilogue

retstruct_d_soft:

bne     t6, FFI_TYPE_STRUCT_D_SOFT, retstruct_f_soft
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
sd      v0, 0(t4)
b       epilogue

retstruct_f_soft:

bne     t6, FFI_TYPE_STRUCT_F_SOFT, retstruct_d_d_soft
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
sw      v0, 0(t4)
b       epilogue

retstruct_d_d_soft:

bne     t6, FFI_TYPE_STRUCT_DD_SOFT, retstruct_f_f_soft
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
sd      v0, 0(t4)
sd      v1, 8(t4)
b       epilogue

retstruct_f_f_soft:

bne     t6, FFI_TYPE_STRUCT_FF_SOFT, retstruct_d_f_soft
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
sw      v0, 0(t4)
sw      v1, 4(t4)
b       epilogue

retstruct_d_f_soft:

bne     t6, FFI_TYPE_STRUCT_DF_SOFT, retstruct_f_d_soft
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
sd      v0, 0(t4)
sw      v1, 8(t4)
b       epilogue

retstruct_f_d_soft:

bne     t6, FFI_TYPE_STRUCT_FD_SOFT, retstruct_small
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
sw      v0, 0(t4)
sd      v1, 8(t4)
b       epilogue

retstruct_small:

bne     t6, FFI_TYPE_STRUCT_SMALL, retstruct_small2
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
REG_S   v0, 0(t4)
b       epilogue

retstruct_small2:

bne     t6, FFI_TYPE_STRUCT_SMALL2, retstruct
jal     t9
REG_L   t4, 4*FFI_SIZEOF_ARG($fp)
REG_S   v0, 0(t4)
REG_S   v1, 8(t4)
b       epilogue

retstruct:

noretval:

jal     t9

# Epilogue

epilogue:

move    $sp, $fp        
REG_L   $fp, SIZEOF_FRAME - 2*FFI_SIZEOF_ARG($sp) # Restore frame pointer
REG_L   ra, SIZEOF_FRAME - 1*FFI_SIZEOF_ARG($sp)  # Restore return address
ADDU    $sp, SIZEOF_FRAME                     # Fix stack pointer
j       ra

.LFE3:

.end    ffi_call_N32

/* ffi_closure_N32. Expects address of the passed-in ffi_closure in t0

($12). Stores any arguments passed in registers onto the stack,
then calls ffi_closure_mips_inner_N32, which then decodes
them.

     Stack layout:

     20 - Start of parameters, original sp
     19 - Called function a7 save
     18 - Called function a6 save
     17 - Called function a5 save
     16 - Called function a4 save
     15 - Called function a3 save
     14 - Called function a2 save
     13 - Called function a1 save
     12 - Called function a0 save
     11 - Called function f19
     10 - Called function f18
      9 - Called function f17
      8 - Called function f16
      7 - Called function f15
      6 - Called function f14
      5 - Called function f13
      4 - Called function f12
      3 - return value high (v1 or $f2)
      2 - return value low (v0 or $f0)
      1 - ra save
      0 - gp save our sp  points here
/

define SIZEOF_FRAME2 (20 * FFI_SIZEOF_ARG)

define A7_OFF2 (19 * FFI_SIZEOF_ARG) define A6_OFF2 (18 * FFI_SIZEOF_ARG) define A5_OFF2 (17 * FFI_SIZEOF_ARG) define A4_OFF2 (16 * FFI_SIZEOF_ARG) define A3_OFF2 (15 * FFI_SIZEOF_ARG) define A2_OFF2 (14 * FFI_SIZEOF_ARG) define A1_OFF2 (13 * FFI_SIZEOF_ARG) define A0_OFF2 (12 * FFI_SIZEOF_ARG)

define F19_OFF2 (11 * FFI_SIZEOF_ARG) define F18_OFF2 (10 * FFI_SIZEOF_ARG) define F17_OFF2 (9 * FFI_SIZEOF_ARG) define F16_OFF2 (8 * FFI_SIZEOF_ARG) define F15_OFF2 (7 * FFI_SIZEOF_ARG) define F14_OFF2 (6 * FFI_SIZEOF_ARG) define F13_OFF2 (5 * FFI_SIZEOF_ARG) define F12_OFF2 (4 * FFI_SIZEOF_ARG)

define V1_OFF2 (3 * FFI_SIZEOF_ARG) define V0_OFF2 (2 * FFI_SIZEOF_ARG)

define RA_OFF2 (1 * FFI_SIZEOF_ARG) define GP_OFF2 (0 * FFI_SIZEOF_ARG)

.align  2
.globl  ffi_closure_N32
.ent    ffi_closure_N32

ffi_closure_N32: .LFB2:

.frame  $sp, SIZEOF_FRAME2, ra
.mask   0x90000000,-(SIZEOF_FRAME2 - RA_OFF2)
.fmask  0x00000000,0
SUBU    $sp, SIZEOF_FRAME2

.LCFI5:

.cpsetup t9, GP_OFF2, ffi_closure_N32
REG_S   ra, RA_OFF2($sp)        # Save return address

.LCFI6:

# Store all possible argument registers. If there are more than
# fit in registers, then they were stored on the stack.
REG_S   a0, A0_OFF2($sp)
REG_S   a1, A1_OFF2($sp)
REG_S   a2, A2_OFF2($sp)
REG_S   a3, A3_OFF2($sp)
REG_S   a4, A4_OFF2($sp)
REG_S   a5, A5_OFF2($sp)
REG_S   a6, A6_OFF2($sp)
REG_S   a7, A7_OFF2($sp)

# Store all possible float/double registers.
s.d     $f12, F12_OFF2($sp)
s.d     $f13, F13_OFF2($sp)
s.d     $f14, F14_OFF2($sp)
s.d     $f15, F15_OFF2($sp)
s.d     $f16, F16_OFF2($sp)
s.d     $f17, F17_OFF2($sp)
s.d     $f18, F18_OFF2($sp)
s.d     $f19, F19_OFF2($sp)

# Call ffi_closure_mips_inner_N32 to do the real work.
LA      t9, ffi_closure_mips_inner_N32
move    a0, $12  # Pointer to the ffi_closure
ADDU    a1, $sp, V0_OFF2
ADDU    a2, $sp, A0_OFF2
ADDU    a3, $sp, F12_OFF2
jalr    t9

# Return flags are in v0
bne     v0, FFI_TYPE_SINT32, cls_retint
lw      v0, V0_OFF2($sp)
b       cls_epilogue

cls_retint:

bne     v0, FFI_TYPE_INT, cls_retfloat
REG_L   v0, V0_OFF2($sp)
b       cls_epilogue

cls_retfloat:

bne     v0, FFI_TYPE_FLOAT, cls_retdouble
l.s     $f0, V0_OFF2($sp)
b       cls_epilogue

cls_retdouble:

bne     v0, FFI_TYPE_DOUBLE, cls_retstruct_d
l.d     $f0, V0_OFF2($sp)
b       cls_epilogue

cls_retstruct_d:

bne     v0, FFI_TYPE_STRUCT_D, cls_retstruct_f
l.d     $f0, V0_OFF2($sp)
b       cls_epilogue

cls_retstruct_f:

bne     v0, FFI_TYPE_STRUCT_F, cls_retstruct_d_d
l.s     $f0, V0_OFF2($sp)
b       cls_epilogue

cls_retstruct_d_d:

bne     v0, FFI_TYPE_STRUCT_DD, cls_retstruct_f_f
l.d     $f0, V0_OFF2($sp)
l.d     $f2, V1_OFF2($sp)
b       cls_epilogue

cls_retstruct_f_f:

bne     v0, FFI_TYPE_STRUCT_FF, cls_retstruct_d_f
l.s     $f0, V0_OFF2($sp)
l.s     $f2, V1_OFF2($sp)
b       cls_epilogue

cls_retstruct_d_f:

bne     v0, FFI_TYPE_STRUCT_DF, cls_retstruct_f_d
l.d     $f0, V0_OFF2($sp)
l.s     $f2, V1_OFF2($sp)
b       cls_epilogue

cls_retstruct_f_d:

bne     v0, FFI_TYPE_STRUCT_FD, cls_retstruct_small2
l.s     $f0, V0_OFF2($sp)
l.d     $f2, V1_OFF2($sp)
b       cls_epilogue

cls_retstruct_small2:

REG_L   v0, V0_OFF2($sp)
REG_L   v1, V1_OFF2($sp)

# Epilogue

cls_epilogue:

REG_L   ra,  RA_OFF2($sp)        # Restore return address
.cpreturn
ADDU    $sp, SIZEOF_FRAME2
j       ra

.LFE2:

.end    ffi_closure_N32

ifdef __GNUC__

.section        .eh_frame,"aw",@progbits

.Lframe1:

.4byte  .LECIE1-.LSCIE1         # length

.LSCIE1:

.4byte  0x0                     # CIE
.byte   0x1                     # Version 1
.ascii  "\000"                  # Augmentation
.uleb128 0x1                    # Code alignment 1
.sleb128 -4                     # Data alignment -4
.byte   0x1f                    # Return Address $31
.byte   0xc                     # DW_CFA_def_cfa
.uleb128 0x1d                   # in $sp
.uleb128 0x0                    # offset 0
.align  EH_FRAME_ALIGN

.LECIE1:

.LSFDE1:

.4byte  .LEFDE1-.LASFDE1        # length.

.LASFDE1:

.4byte  .LASFDE1-.Lframe1       # CIE_pointer.
FDE_ADDR_BYTES  .LFB3           # initial_location.
FDE_ADDR_BYTES  .LFE3-.LFB3     # address_range.
.byte   0x4                     # DW_CFA_advance_loc4
.4byte  .LCFI0-.LFB3            # to .LCFI0
.byte   0xe                     # DW_CFA_def_cfa_offset
.uleb128 SIZEOF_FRAME           # adjust stack.by SIZEOF_FRAME
.byte   0x4                     # DW_CFA_advance_loc4
.4byte  .LCFI1-.LCFI0           # to .LCFI1
.byte   0x9e                    # DW_CFA_offset of $fp
.uleb128 2*FFI_SIZEOF_ARG/4     # 
.byte   0x9f                    # DW_CFA_offset of ra
.uleb128 1*FFI_SIZEOF_ARG/4     # 
.byte   0x4                     # DW_CFA_advance_loc4
.4byte  .LCFI3-.LCFI1           # to .LCFI3
.byte   0xd                     # DW_CFA_def_cfa_register
.uleb128 0x1e                   # in $fp
.align  EH_FRAME_ALIGN

.LEFDE1: .LSFDE3:

.4byte  .LEFDE3-.LASFDE3        # length

.LASFDE3:

.4byte  .LASFDE3-.Lframe1       # CIE_pointer.
FDE_ADDR_BYTES  .LFB2           # initial_location.
FDE_ADDR_BYTES  .LFE2-.LFB2     # address_range.
.byte   0x4                     # DW_CFA_advance_loc4
.4byte  .LCFI5-.LFB2            # to .LCFI5
.byte   0xe                     # DW_CFA_def_cfa_offset
.uleb128 SIZEOF_FRAME2          # adjust stack.by SIZEOF_FRAME
.byte   0x4                     # DW_CFA_advance_loc4
.4byte  .LCFI6-.LCFI5           # to .LCFI6
.byte   0x9c                    # DW_CFA_offset of $gp ($28)
.uleb128 (SIZEOF_FRAME2 - GP_OFF2)/4
.byte   0x9f                    # DW_CFA_offset of ra ($31)
.uleb128 (SIZEOF_FRAME2 - RA_OFF2)/4
.align  EH_FRAME_ALIGN

.LEFDE3: endif /* __GNUC__ */

endif