diff options
| author | Jeff Johnston <jjohnstn@redhat.com> | 2002-11-07 03:25:57 +0300 |
|---|---|---|
| committer | Jeff Johnston <jjohnstn@redhat.com> | 2002-11-07 03:25:57 +0300 |
| commit | 5b30331167ffba6aef06fb3ad9685b792af816ce (patch) | |
| tree | bac6dd1994bdbeb501ed9d049c4504e01ec63c4f /libgloss/arm/redboot-crt0.S | |
| parent | c27382bdbeb9ac583b77c148239ccd011b663c50 (diff) | |
2002-11-08 Jeff Johnston <jjohnstn@redhat.com>
* arm/Makefile.in: Add support for new pid specs.
* arm/coff-iq80310.specs: Change to allow future support.
* arm/elf-iq80310.specs: Ditto.
* arm/elf-redboot.specs: Ditto.
* arm/coff-redboot.ld: Add EH frame support.
* arm/redboot-crt0.S: Add optional code to clear bss without
memset.
* arm/coff-pid.specs: New file.
* arm/elf-pid.specs: New file.
Diffstat (limited to 'libgloss/arm/redboot-crt0.S')
| -rw-r--r-- | libgloss/arm/redboot-crt0.S | 43 |
1 files changed, 28 insertions, 15 deletions
diff --git a/libgloss/arm/redboot-crt0.S b/libgloss/arm/redboot-crt0.S index e14559a59..f2963eeb4 100644 --- a/libgloss/arm/redboot-crt0.S +++ b/libgloss/arm/redboot-crt0.S @@ -1,4 +1,3 @@ - .file "crt0.S" @@ -12,30 +11,44 @@ #endif .text - /* - * Setup the assembly entry point. - */ + /* Setup the assembly entry point. */ .code 32 .globl SYM_NAME(start) .globl SYM_NAME(_start) SYM_NAME(start): SYM_NAME(_start): - mov fp, #0 /* Null frame pointer */ - mov r7, #0 /* Null frame pointer for Thumb */ + mov fp, #0 /* Null frame pointer. */ + mov r7, #0 /* Null frame pointer for Thumb. */ - /* enable interrupts for gdb debugging */ + /* Enable interrupts for gdb debugging. */ mrs r0, cpsr bic r0, r0, #0xC0 msr cpsr, r0 - mov a2, #0 /* Second arg: fill value */ - ldr a1, .LC1 /* First arg: start of memory block */ + mov a2, #0 /* Second arg: fill value. */ + ldr a1, .LC1 /* First arg: start of memory block. */ ldr a3, .LC2 - sub a3, a3, a1 /* Third arg: length of block */ + sub a3, a3, a1 /* Third arg: length of block. */ + +#ifdef GCRT0 + /* Zero out the bss without using memset. + Using memset is bad because it may be instrumented for + profiling, but at this point, the profiling data structures + have not been set up. + FIXME: This loop could be a lot more efficient. */ + subs a3, a3, #0 + beq 2f +1: strb a2, [a1] + subs a3, a3, #1 + add a1, a1, #1 + bne 1b +2: + /* Nothing to left to clear. */ +#endif -#ifdef __thumb__ /* Enter Thumb mode.... */ - add a4, pc, #1 /* Get the address of the Thumb block */ - bx a4 /* Go there and start Thumb decoding */ +#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 @@ -43,8 +56,9 @@ SYM_NAME(_start): __change_mode: #endif +#ifndef GCRT0 bl SYM_NAME(memset) - +#endif bl SYM_NAME(__get_memtop) sub r0, r0, #32 mov sp, r0 @@ -76,7 +90,6 @@ __change_mode: .Lfini: .word SYM_NAME(_fini) #endif - #if 0 #ifdef __thumb__ .code 16 |