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#include "swi.h"
/* ANSI concatenation macros. */
#define CONCAT(a, b) CONCAT2(a, b)
#define CONCAT2(a, b) a ## b
#ifdef __USER_LABEL_PREFIX__
#define FUNCTION( name ) CONCAT (__USER_LABEL_PREFIX__, name)
#else
#error __USER_LABEL_PREFIX is not defined
#endif
/* .text is used instead of .section .text so it works with arm-aout too. */
.text
.code 32
.align 0
.global _mainCRTStartup
.global _start
.global start
start:
_start:
_mainCRTStartup:
/* Start by setting up a stack */
#ifdef ARM_RDP_MONITOR
/* Issue Demon SWI to read stack info */
swi SWI_GetEnv /* Returns command line in r0 */
mov sp,r1 /* and the highest memory address in r1 */
ldr sl, .LC2 /* stack limit is at end of data */
add sl, sl, #256 /* allow slop for stack overflow handling */
/* and small frames */
#else
#ifdef ARM_RDI_MONITOR
/* Issue Angel SWI to read stack info */
mov r0, #AngelSWI_Reason_HeapInfo
adr r1, .LC0 /* point at ptr to 4 words to receive data */
swi AngelSWI_ARM /* We are always in ARM mode for startup */
ldr r0, .LC0 /* point at values read */
ldr sp, [r0, #8]
ldr sl, [r0, #12]
add sl, sl, #256 /* allow slop for stack overflow handling */
/* and small frames */
#else
/* Set up the stack pointer to a fixed value */
ldr r3, .LC0
mov sp, r3
/* Setup a default stack-limit in-case the code has been
compiled with "-mapcs-stack-check". Hard-wiring this value
is not ideal, since there is currently no support for
checking that the heap and stack have not collided, or that
this default 64k is enough for the program being executed.
However, it ensures that this simple crt0 world will not
immediately cause an overflow event: */
sub sl, sp, #64 << 10 /* Still assumes 256bytes below sl */
#endif
#endif
mov a2, #0 /* Second arg: fill value */
mov fp, a2 /* Null frame pointer */
mov r7, a2 /* Null frame pointer for Thumb */
ldr a1, .LC1 /* First arg: start of memory block */
ldr a3, .LC2
sub a3, a3, a1 /* Third arg: length of block */
#ifdef __thumb__ /* Enter Thumb mode.... */
add a4, pc, #1 /* Get the address of the Thumb block */
bx a4 /* Go there and start Thumb decoding */
.code 16
.global __change_mode
.thumb_func
__change_mode:
#endif
bl FUNCTION (memset)
#if !defined (ARM_RDP_MONITOR) && !defined (ARM_RDI_MONITOR)
mov r0, #0 /* no arguments */
mov r1, #0 /* no argv either */
#else
/* Need to set up standard file handles */
bl FUNCTION (initialise_monitor_handles)
#ifdef ARM_RDP_MONITOR
swi SWI_GetEnv /* sets r0 to point to the command line */
mov r1, r0
#else
mov r0, #AngelSWI_Reason_GetCmdLine
adr r1, .LC30 /* Space for command line */
swi AngelSWI
ldr r1, .LC30
#endif
/* Parse string at r1 */
mov r0, #0 /* count of arguments so far */
.LC10:
/* Skip leading blanks */
#ifdef __thumb__
ldrb r3, [r1]
add r1, #1
#else
ldrb r3, [r1], #1
#endif
cmp r3, #0
beq .LC12
cmp r3, #' '
beq .LC10
/* See whether we are scanning a string */
cmp r3, #'"'
#ifdef __thumb__
beq .LC20
cmp r3, #'\''
bne .LC21
.LC20:
mov r2, r3
b .LC22
.LC21:
mov r2, #' ' /* terminator type */
sub r1, r1, #1 /* adjust back to point at start char */
.LC22:
#else
cmpne r3, #'\''
moveq r2, r3
movne r2, #' ' /* terminator type */
subne r1, r1, #1 /* adjust back to point at start char */
#endif
/* Stack a pointer to the current argument */
#ifdef __thumb__
push {r1}
#else
stmfd sp!, {r1}
#endif
add r0, r0, #1
.LC11:
#ifdef __thumb__
ldrb r3, [r1]
add r1, #1
#else
ldrb r3, [r1], #1
#endif
cmp r3, #0
beq .LC12
cmp r2, r3 /* reached terminator? */
bne .LC11
mov r2, #0
sub r3, r1, #1
strb r2, [r3] /* terminate the arg string */
b .LC10
.LC12:
mov r1, sp /* point at stacked arg pointers */
/* We've now got the stacked args in order reverse the */
#ifdef __thumb__
mov r2, r0
lsl r2, #2
add r2, sp
mov r3, sp
.LC15: cmp r2, r3
bls .LC14
sub r2, #4
ldr r4, [r2]
ldr r5, [r3]
str r5, [r2]
str r4, [r3]
add r3, #4
b .LC15
.LC14:
#else
add r2, sp, r0, LSL #2 /* End of args */
mov r3, sp /* Start of args */
.LC13: cmp r2, r3
ldrhi r4,[r2, #-4] /* Reverse ends of list */
ldrhi r5, [r3]
strhi r5, [r2, #-4]!
strhi r4, [r3], #4
bhi .LC13
#endif
#endif
bl FUNCTION (main)
bl FUNCTION (exit) /* Should not return */
#ifdef __thumb__
/* Come out of Thumb mode... This code should be redundant... */
mov a4, pc
bx a4
.code 32
.global change_back
change_back:
/* Halt the execution. This code should never be executed. */
/*
** With no debug monitor, this probably aborts (eventually).
** With a Demon debug monitor, this halts cleanly.
** With an Angel debug monitor, this will report 'Unknown SWI'.
*/
swi SWI_Exit
#endif
/* For Thumb, constants must be after the code since only
positive offsets are supported for PC relative addresses. */
.align 0
.LC0:
#ifdef ARM_RDI_MONITOR
.word HeapBase
#else
#ifndef ARM_RDP_MONITOR
#ifdef __pe__
.word 0x800000
#else
/* .word 0x80000 */ /* Top of RAM on the PIE board */
#endif
#endif
#endif
.LC1:
.word __bss_start__
.LC2:
.word __bss_end__
#ifdef ARM_RDI_MONITOR
.LC30: .word CommandLine
/* Workspace for Angel calls. */
.data
/* Data returned by monitor SWI */
HeapBase: .word 0
HeapLimit: .word 0
StackBase: .word 0
StackLimit: .word 0
CommandLine: .space 256,0 /* Maximum length of 255 chars handled */
#endif
#ifdef __pe__
.section .idata$3
.long 0,0,0,0,0,0,0,0
#endif
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