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@@ -12,39 +12,35 @@
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a2=argv[0]
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a3=argv[argc+1]
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-This file now uses the register naming from the ARM Procedure Calling Standard
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-
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- Name Number APCS Role
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-
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- a1 0 argument 1 / integer result / scratch register / argc
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- a2 1 argument 2 / scratch register / argv
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- a3 2 argument 3 / scratch register / envp
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- a4 3 argument 4 / scratch register
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- v1 4 register variable
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- v2 5 register variable
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- v3 6 register variable
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- v4 7 register variable
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- v5 8 register variable
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- sb/v6 9 static base / register variable
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- sl/v7 10 stack limit / stack chunk handle / reg. variable
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- fp 11 frame pointer
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- ip 12 scratch register / new-sb in inter-link-unit calls
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- sp 13 lower end of current stack frame
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- lr 14 link address / scratch register
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- pc 15 program counter
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+ARM register quick reference:
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+
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+ Name Number ARM Procedure Calling Standard Role
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+
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+ a1 r0 argument 1 / integer result / scratch register / argc
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+ a2 r1 argument 2 / scratch register / argv
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+ a3 r2 argument 3 / scratch register / envp
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+ a4 r3 argument 4 / scratch register
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+ v1 r4 register variable
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+ v2 r5 register variable
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+ v3 r6 register variable
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+ v4 r7 register variable
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+ v5 r8 register variable
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+ sb/v6 r9 static base / register variable
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+ sl/v7 r10 stack limit / stack chunk handle / reg. variable
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+ fp r11 frame pointer
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+ ip r12 scratch register / new-sb in inter-link-unit calls
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+ sp r13 lower end of current stack frame
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+ lr r14 link address / scratch register
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+ pc r15 program counter
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*/
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.text
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- .align 2
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- .global __environ
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.global _start
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- .global exit
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- .global main
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+ .global __uClibc_main
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.type _start,%function
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- .type exit,%function
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- .type main,%function
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+ .type __uClibc_main,%function
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.text
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_start:
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@@ -52,35 +48,17 @@ _start:
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/* clear the frame pointer */
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mov fp, #0
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- /* Load register a1 (argc) from the stack to its final resting place */
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- ldr a1, [sp], #4
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-
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- /* Copy argv pointer into a2 -- which its final resting place */
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- mov a2, sp
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-
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- /* Set up environ, skip to the end of argv, and put
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- * a pointer to whatever we find there (hopefully the
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- environment) in a3 */
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- ldr a4, .L3
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- add a3, a2, a1, lsl #2
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- add a3, a3, #4
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- str a3, [a4, #0]
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+ /* Load register r0 (argc) from the stack to its final resting place */
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+ ldr r0, [sp], #4
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- bl main
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- bl exit
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+ /* Copy argv pointer into r1 -- which its final resting place */
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+ mov r1, sp
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-.align 2
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-.L3:
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- .word __environ
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-
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-
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-.data
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- .align 2
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- .global __environ
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-
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-__environ:
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- .long 0
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+ /* Skip to the end of argv and put a pointer to whatever
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+ we find there (hopefully the environment) in a3 */
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+ add r2, r1, r0, lsl #2
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+ add r2, r2, #4
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-.weak environ
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-environ = __environ
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+ /* Ok, now run uClibc's main() -- shouldn't return */
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+ bl __uClibc_main
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