From 4e7b770ecb522ef26f9ff91ebb8dae67f20fda0f Mon Sep 17 00:00:00 2001 From: Eric Andersen Date: Fri, 10 Jun 2005 09:18:20 +0000 Subject: Dunno yet if I got this right or not, but it now at least has a chance of perhaps working... --- libc/sysdeps/linux/arm/Makefile | 16 ++-- libc/sysdeps/linux/arm/crt0.S | 142 ----------------------------------- libc/sysdeps/linux/arm/crt1.S | 161 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 169 insertions(+), 150 deletions(-) delete mode 100644 libc/sysdeps/linux/arm/crt0.S create mode 100644 libc/sysdeps/linux/arm/crt1.S (limited to 'libc') diff --git a/libc/sysdeps/linux/arm/Makefile b/libc/sysdeps/linux/arm/Makefile index ca41ff6e7..f25d0b523 100644 --- a/libc/sysdeps/linux/arm/Makefile +++ b/libc/sysdeps/linux/arm/Makefile @@ -19,9 +19,9 @@ TOPDIR=../../../../ include $(TOPDIR)Rules.mak -CRT0_SRC = crt0.S -CRT0_OBJ = crt1.o -SCRT0_OBJ = $(patsubst %,S%, $(CRT0_OBJ)) +CRT_SRC = crt1.S +CRT_OBJ = crt1.o +SCRT_OBJ = $(patsubst %,S%, $(CRT_OBJ)) CTOR_TARGETS=$(TOPDIR)lib/crti.o $(TOPDIR)lib/crtn.o SSRC=__longjmp.S vfork.S clone.S setjmp.S bsd-setjmp.S \ @@ -31,22 +31,22 @@ SOBJS=$(patsubst %.S,%.o, $(SSRC)) CSRC=brk.c syscall.c ioperm.c sigaction.c COBJS=$(patsubst %.c,%.o, $(CSRC)) -OBJS=$(SOBJS) $(MOBJ) $(COBJS) +OBJS=$(SOBJS) $(COBJS) OBJ_LIST=../../../obj.sysdeps.$(TARGET_ARCH) all: $(OBJ_LIST) -$(OBJ_LIST): $(OBJS) $(CRT0_OBJ) $(SCRT0_OBJ) $(CTOR_TARGETS) +$(OBJ_LIST): $(OBJS) $(CRT_OBJ) $(SCRT_OBJ) $(CTOR_TARGETS) echo $(patsubst %, sysdeps/linux/$(TARGET_ARCH)/%, $(OBJS)) > $(OBJ_LIST) $(INSTALL) -d $(TOPDIR)lib/ - cp $(CRT0_OBJ) $(SCRT0_OBJ) $(TOPDIR)lib/ + cp $(CRT_OBJ) $(SCRT_OBJ) $(TOPDIR)lib/ -$(CRT0_OBJ): $(CRT0_SRC) +$(CRT_OBJ): $(CRT_SRC) $(CC) $(ASFLAGS) -DL_$* $< -c -o $*.o $(STRIPTOOL) -x -R .note -R .comment $*.o -$(SCRT0_OBJ): $(CRT0_SRC) +$(SCRT_OBJ): $(CRT_SRC) $(CC) $(ASFLAGS) $(PIEFLAG) -DL_$* $< -c -o $*.o $(STRIPTOOL) -x -R .note -R .comment $*.o diff --git a/libc/sysdeps/linux/arm/crt0.S b/libc/sysdeps/linux/arm/crt0.S deleted file mode 100644 index 4f4a8cefd..000000000 --- a/libc/sysdeps/linux/arm/crt0.S +++ /dev/null @@ -1,142 +0,0 @@ -/* When we enter this piece of code, the program stack looks like this: - argc argument counter (integer) - argv[0] program name (pointer) - argv[1...N] program args (pointers) - argv[argc-1] end of args (integer) - NULL - env[0...N] environment variables (pointers) - NULL - - For uClinux it looks like this: - - argc argument counter (integer) - argv char *argv[] - envp char *envp[] - argv[0] program name (pointer) - argv[1...N] program args (pointers) - argv[argc-1] end of args (integer) - NULL - env[0...N] environment variables (pointers) - NULL - - When we are done here, we want - a1=argc - a2=argv[0] - a3=argv[argc+1] - -ARM register quick reference: - - Name Number ARM Procedure Calling Standard Role - - a1 r0 argument 1 / integer result / scratch register / argc - a2 r1 argument 2 / scratch register / argv - a3 r2 argument 3 / scratch register / envp - a4 r3 argument 4 / scratch register - v1 r4 register variable - v2 r5 register variable - v3 r6 register variable - v4 r7 register variable - v5 r8 register variable - sb/v6 r9 static base / register variable - sl/v7 r10 stack limit / stack chunk handle / reg. variable - fp r11 frame pointer - ip r12 scratch register / new-sb in inter-link-unit calls - sp r13 lower end of current stack frame - lr r14 link address / scratch register - pc r15 program counter -*/ - -#include - -.text - .global _start - .type _start,%function - .weak _init - .weak _fini - .type __uClibc_start_main,%function -/* Stick in a dummy reference to main(), so that if an application - * is linking when the main() function is in a static library (.a) - * we can be sure that main() actually gets linked in */ - .type main,%function - - -.text -_start: - /* clear the frame pointer */ - mov fp, #0 - -#ifdef __ARCH_HAS_MMU__ - /* Load register r0 (argc) from the stack to its final resting place */ - ldr r0, [sp], #4 - - /* Copy argv pointer into r1 -- which its final resting place */ - mov r1, sp - - /* Skip to the end of argv and put a pointer to whatever - we find there (hopefully the environment) in r2 */ - add r2, r1, r0, lsl #2 - add r2, r2, #4 - -#else - /* - * uClinux stacks look a little different from normal - * MMU-full Linux stacks (for no good reason) - */ - /* pull argc, argv and envp off the stack */ - ldr r0,[sp, #0] - ldr r1,[sp, #4] - ldr r2,[sp, #8] -#endif - -#ifdef __PIC__ - /* Store the address of _init in r3 as an argument to main() */ - adr r5, .L_init - ldr r3, .L_init - add r3, r3, r5 - - /* Push _fini onto the stack as the final argument to main() */ - ldr r4, .L_init + 4 - add r4, r4, r5 -#else - /* Store the address of _init in r3 as an argument to main() */ - ldr r3, =_init - - /* Push _fini onto the stack as the final argument to main() */ - ldr r4, =_fini -#endif - stmfd sp!, {r4} - - /* Ok, now run uClibc's main() -- shouldn't return */ - bl __uClibc_start_main - - /* Crash if somehow `exit' returns anyways. */ - bl abort - -#ifdef __PIC__ -.L_init: - .word _init - .L_init - .word _fini - .L_init -#endif - -/* We need this stuff to make gdb behave itself, otherwise - gdb will chokes with SIGILL when trying to debug apps. -*/ - .section ".note.ABI-tag", "a" - .align 4 - .long 1f - 0f - .long 3f - 2f - .long 1 -0: .asciz "GNU" -1: .align 4 -2: .long 0 - .long 2,0,0 -3: .align 4 - -/* Define a symbol for the first piece of initialized data. */ - .data - .globl __data_start -__data_start: - .long 0 - .weak data_start - data_start = __data_start - diff --git a/libc/sysdeps/linux/arm/crt1.S b/libc/sysdeps/linux/arm/crt1.S new file mode 100644 index 000000000..3bea01e73 --- /dev/null +++ b/libc/sysdeps/linux/arm/crt1.S @@ -0,0 +1,161 @@ +/* When we enter this piece of code, the program stack looks like this: + argc argument counter (integer) + argv[0] program name (pointer) + argv[1...N] program args (pointers) + argv[argc-1] end of args (integer) + NULL + env[0...N] environment variables (pointers) + NULL + + For uClinux it looks like this: + + argc argument counter (integer) + argv char *argv[] + envp char *envp[] + argv[0] program name (pointer) + argv[1...N] program args (pointers) + argv[argc-1] end of args (integer) + NULL + env[0...N] environment variables (pointers) + NULL + + When we are done here, we want + a1=argc + a2=argv[0] + a3=argv[argc+1] + +ARM register quick reference: + + Name Number ARM Procedure Calling Standard Role + + a1 r0 argument 1 / integer result / scratch register / argc + a2 r1 argument 2 / scratch register / argv + a3 r2 argument 3 / scratch register / envp + a4 r3 argument 4 / scratch register + v1 r4 register variable + v2 r5 register variable + v3 r6 register variable + v4 r7 register variable + v5 r8 register variable + sb/v6 r9 static base / register variable + sl/v7 r10 stack limit / stack chunk handle / reg. variable + fp r11 frame pointer + ip r12 scratch register / new-sb in inter-link-unit calls + sp r13 lower end of current stack frame + lr r14 link address / scratch register + pc r15 program counter +*/ + +#include + +.text + .global _start + .type _start,%function + .type _init,%function + .type _fini,%function + .type main,%function + .type __uClibc_main,%function + + +.text +_start: + /* clear the frame pointer */ + mov fp, #0 + +#ifdef __PIC__ + /* Store the address of main in r0 */ + adr r5, .L_main + ldr r0, .L_main + add r0, r0, r5 + +#else + /* Store the address of main in r0 */ + ldr r0, =main +#endif + +#ifdef __ARCH_HAS_MMU__ + + /* Load register r1 (argc) from the stack to its final resting place */ + ldr r1, [sp], #4 + + /* Copy argv pointer into r2 -- which its final resting place */ + mov r2, sp +#else + /* + * uClinux stacks look a little different from normal + * MMU-full Linux stacks (for no good reason) + */ + /* pull argc, argv and envp off the stack */ + ldr r1,[sp, #0] + ldr r2,[sp, #4] +#endif + +#ifdef __PIC__ + /* Store the address of _init in r3 */ + adr r5, .L_init + ldr r3, .L_init + add r3, r3, r5 + + /* Push _fini onto the stack as an argument to main() */ + ldr r4, .L_init + 4 + add r4, r4, r5 + stmfd sp!, {r4} + + /* Push rtld_fini onto the stack as an argument to main() */ + ldr r4, .L_init + 8 + add r4, r4, r5 + stmfd sp!, {r4} +#else + /* Store the address of _init in r3 as an argument to main() */ + ldr r3, =_init + + /* Push _fini onto the stack as an argument to main() */ + ldr r4, =_fini + stmfd sp!, {r4} + + /* Push rtld_fini onto the stack as an argument to main() */ + ldr r4, =rtld_fini + stmfd sp!, {r4} +#endif + + /* We need to call __uClibc_main which should not return. + __uClibc_main (int (*main) (int, char **, char **), int argc, + char **argv, void (*init) (void), void (*fini) (void), + void (*rtld_fini) (void), void *stack_end) + */ + bl __uClibc_main + + /* Crash if somehow `exit' returns anyways. */ + bl abort + +#ifdef __PIC__ +.L_init: + .word _init + .word _fini + .word rtld_fini +.L_main: + .word main +#endif + +/* We need this stuff to make gdb behave itself, otherwise + gdb will choke with SIGILL when trying to debug apps. +*/ + .section ".note.ABI-tag", "a" + .align 4 + .long 1f - 0f + .long 3f - 2f + .long 1 +0: .asciz "GNU" +1: .align 4 +2: .long 0 + .long 2,0,0 +3: .align 4 + +/* Define a symbol for the first piece of initialized data. */ + .data + .globl __data_start +__data_start: + .long 0 + .weak data_start + data_start = __data_start + -- cgit v1.2.3