diff options
Diffstat (limited to 'packages/uclibc/uclibc-0.9.28/thumb-mov-pc-bx.patch')
| -rw-r--r-- | packages/uclibc/uclibc-0.9.28/thumb-mov-pc-bx.patch | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/packages/uclibc/uclibc-0.9.28/thumb-mov-pc-bx.patch b/packages/uclibc/uclibc-0.9.28/thumb-mov-pc-bx.patch new file mode 100644 index 0000000000..86713a7678 --- /dev/null +++ b/packages/uclibc/uclibc-0.9.28/thumb-mov-pc-bx.patch @@ -0,0 +1,102 @@ +# This patch changes all cases where the ARM assembler mov pc,rx +# instructions are used to ensure that the thumb/arm interwork change of +# process more works - in essence mov pc,rx needs to become bx rc. +# +# The ldr pc or ldm rx, {pc} instructions are not changed - this is +# fine on ARM >=v5 but will fail to restore thumb mode on ARM v4T, +# i.e. this code will not provide support for thumb on ARM v4T. +# +# One mov pc is left in resolve.S, this is fixed in a different patch - +# thumb-resolve.patch +# +# The changes are protected by __THUMB_INTERWORK__ - the original +# mov instruction will work on newer architectures and is required on +# arch v4 (not v4t) and earlier - those which did not support thumb - +# so this is safe. See gcc lib1asmfuncs for a more exact test. +# +--- uClibc-0.9.28/.pc/thumb-mov-pc-bx.patch/ldso/ldso/arm/dl-startup.h 2005-08-17 15:49:41.000000000 -0700 ++++ uClibc-0.9.28/ldso/ldso/arm/dl-startup.h 2005-09-08 09:34:22.918316874 -0700 +@@ -8,6 +8,7 @@ + " .text\n" + " .globl _start\n" + " .type _start,%function\n" ++ " .arm\n" + "_start:\n" + " @ at start time, all the args are on the stack\n" + " mov r0, sp\n" +@@ -40,7 +41,11 @@ + " ldr r0, .L_FINI_PROC\n" + " ldr r0, [sl, r0]\n" + " @ jump to the user_s entry point\n" ++#if defined(__THUMB_INTERWORK__) ++ " bx r6\n" ++#else + " mov pc, r6\n" ++#endif + ".L_GET_GOT:\n" + " .word _GLOBAL_OFFSET_TABLE_ - .L_GOT_GOT - 4\n" + ".L_SKIP_ARGS:\n" +--- uClibc-0.9.28/.pc/thumb-mov-pc-bx.patch/ldso/ldso/arm/dl-sysdep.h 2005-08-17 15:49:41.000000000 -0700 ++++ uClibc-0.9.28/ldso/ldso/arm/dl-sysdep.h 2005-09-07 20:10:35.923583424 -0700 +@@ -85,7 +85,19 @@ + extern void __dl_start asm ("_dl_start"); + Elf32_Addr got_addr = (Elf32_Addr) &__dl_start; + Elf32_Addr pcrel_addr; ++#if !defined(__thumb__) ++ /* On thumb this has to be two instructions because ++ * the offset is negative. ++ */ + asm ("adr %0, _dl_start" : "=r" (pcrel_addr)); ++#else ++ /* This is dumb, gcc should support a thumb adrl ++ * but it doesn't, so this is the same thing the ++ * hard way. If this code moves too far from _dl_start ++ * it will fail. ++ */ ++ asm ("adr\t%0, 1f\n1:\tsub\t%0, #1b-_dl_start\n" : "=r" (pcrel_addr)); ++#endif + return pcrel_addr - got_addr; + } + +--- uClibc-0.9.28/.pc/thumb-mov-pc-bx.patch/libc/sysdeps/linux/arm/clone.S 2005-08-17 15:49:41.000000000 -0700 ++++ uClibc-0.9.28/libc/sysdeps/linux/arm/clone.S 2005-09-08 09:36:24.801986529 -0700 +@@ -51,7 +51,11 @@ + swi __NR_clone + movs a1, a1 + blt __error +- movne pc, lr ++#if defined(__THUMB_INTERWORK__) ++ bxne lr ++#else ++ movne pc, lr ++#endif + + @ pick the function arg and call address off the stack and execute + ldr r0, [sp, #4] +--- uClibc-0.9.28/.pc/thumb-mov-pc-bx.patch/libc/sysdeps/linux/arm/vfork.S 2005-08-17 15:49:41.000000000 -0700 ++++ uClibc-0.9.28/libc/sysdeps/linux/arm/vfork.S 2005-09-08 09:51:13.377901086 -0700 +@@ -34,7 +34,11 @@ + #ifdef __NR_vfork + swi __NR_vfork + cmn r0, #4096 ++#if defined(__THUMB_INTERWORK__) ++ bxcc lr ++#else + movcc pc, lr ++#endif + + /* Check if vfork even exists. */ + ldr r1, =-ENOSYS +@@ -47,7 +51,11 @@ + cmn r0, #4096 + + /* Syscal worked. Return to child/parent */ +- movcc pc, lr ++#if defined(__THUMB_INTERWORK__) ++ bxcc lr ++#else ++ movcc pc, lr ++#endif + + __error: + b __syscall_error |