0
+ − 1 /*
+ − 2
+ − 3 Package: dyncall
+ − 4 Library: dyncall
+ − 5 File: dyncall/dyncall_call_arm32_thumb_apple.s
+ − 6 Description: ARM Thumb call kernel implementation for apple assembler.
+ − 7 License:
+ − 8
+ − 9 Copyright (c) 2007-2011 Daniel Adler <dadler@uni-goettingen.de>,
+ − 10 Tassilo Philipp <tphilipp@potion-studios.com>
+ − 11
+ − 12 Permission to use, copy, modify, and distribute this software for any
+ − 13 purpose with or without fee is hereby granted, provided that the above
+ − 14 copyright notice and this permission notice appear in all copies.
+ − 15
+ − 16 THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ − 17 WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ − 18 MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ − 19 ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ − 20 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ − 21 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ − 22 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ − 23
+ − 24 */
+ − 25
+ − 26
+ − 27 .text
+ − 28 .thumb
+ − 29 .code 16
+ − 30 .globl _dcCall_arm32_thumb
+ − 31
+ − 32 /* Main dyncall call. */
+ − 33 .thumb_func
+ − 34 _dcCall_arm32_thumb:
+ − 35
+ − 36 /* Prolog. This function never needs to spill inside its prolog, so just store the permanent registers. */
+ − 37 push {r4-r7, r14} /* Frame ptr, permanent registers, link register -> save area on stack. */
+ − 38 mov r7, r13 /* Set frame ptr. */
+ − 39
+ − 40 /* Call. */
+ − 41 mov r4, r0 /* Move 'fptr' to r4 (1st argument is passed in r0). */
+ − 42
+ − 43 /* Disable 'thumb' address forcing... */
+ − 44
+ − 45 /* mov r0, #1 */ /* Assure that LSB is set to 1 (THUMB call). - Not Required and not useful for interworking calls */
+ − 46 /* orr r4, r0 */
+ − 47
+ − 48 mov r5, r1 /* Move 'args' to r5 (2nd argument is passed in r1). */
+ − 49 mov r6, r2 /* Move 'size' to r6 (3rd argument is passed in r2). */
+ − 50
+ − 51 cmp r6, #16 /* Jump to call if no more than 4 arguments. */
+ − 52 ble call
+ − 53
+ − 54 sub r6, #16 /* Size of remaining arguments. */
+ − 55 mov r0, r13 /* Set stack pointer to top of stack. */
+ − 56 sub r0, r0, r6
+ − 57 lsr r0, #3 /* Align stack on 8 byte boundaries. */
+ − 58 lsl r0, #3
+ − 59 mov r13, r0
+ − 60
+ − 61 add r1, #16 /* Let r1 point to remaining arguments. */
+ − 62 mov r2, #0 /* Init byte counter to 0. */
+ − 63 .thumb_func
+ − 64 pushArgs:
+ − 65 ldrb r3, [r1, r2] /* Load a byte into r3. */
+ − 66 strb r3, [r0, r2] /* Push byte onto stack. */
+ − 67 add r2, r2, #1 /* Increment byte counter. */
+ − 68 cmp r2, r6
+ − 69 bne pushArgs
+ − 70 .thumb_func
+ − 71 call:
+ − 72 ldmia r5!, {r0-r3} /* Load first 4 arguments for new call into r0-r3. */
+ − 73
+ − 74 /* 'blx %r4' workaround for ARMv4t in THUMB: */
+ − 75 blx r4 /* Branch and force THUMB-mode return (LR bit 0 set). */
+ − 76
+ − 77 /* Epilog. */
+ − 78 mov r13, r7 /* Reset stack ptr. */
+ − 79 pop {r4-r7, r15} /* Restore permanent registers and program counter. (Force a stay in THUMB in ARMv4, whether ARMv5 can return in ARM or THUMB depending on the bit 0. */
+ − 80
