diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S')
| -rw-r--r-- | sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S b/sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S new file mode 100644 index 0000000000..b875aa5de0 --- /dev/null +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S @@ -0,0 +1,105 @@ +/* Set up a context to call a function. + Copyright (C) 2002 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <sysdep.h> + +#define __ASSEMBLY__ +#include <asm/ptrace.h> +#include "ucontext_i.h" + +ENTRY(__makecontext) + /* Set up the first 7 args to the function in its registers */ + stw r6,_UC_GREGS+(PT_R3*4)(r3) + stw r7,_UC_GREGS+(PT_R4*4)(r3) + stw r8,_UC_GREGS+(PT_R5*4)(r3) + stw r9,_UC_GREGS+(PT_R6*4)(r3) + stw r10,_UC_GREGS+(PT_R7*4)(r3) + lwz r8,8(r1) + lwz r9,12(r1) + stw r8,_UC_GREGS+(PT_R8*4)(r3) + stw r9,_UC_GREGS+(PT_R9*4)(r3) + + /* Set the NIP to the start of the function */ + stw r4,_UC_GREGS+(PT_NIP*4)(r3) + + /* Set the function's r31 to ucp->uc_link for the exitcode below. */ + lwz r7,_UC_LINK(r3) + stw r7,_UC_GREGS+(PT_R31*4)(r3) + + /* Set the function's LR to point to the exitcode below. */ +#ifdef PIC + mflr r0 + bl 1f +1: mflr r6 + addi r6,r6,L(exitcode)-1b + mtlr r0 +#else + lis r6,L(exitcode)@ha + addi r6,r6,L(exitcode)@l +#endif + stw r6,_UC_GREGS+(PT_LNK*4)(r3) + + /* + * Set up the stack frame for the function. + * If we have more than 5 args to the function (8 args to makecontext), + * there will be some arguments on the stack which have to end up + * in registers. If there are more than 8 args to the function, + * we have to copy (argc - 8) args from our stack to the functions' + * stack (and allow space for them in the frame). + */ + lwz r4,_UC_STACK_SP(r3) + lwz r8,_UC_STACK_SIZE(r3) + add r4,r4,r8 + rlwinm r4,r4,0,0,27 /* round down to 16-byte boundary */ + addi r7,r4,-16 /* stack frame for fn's caller */ + cmpwi r5,8 + blt 2f /* less than 8 args is easy */ + lwz r10,16(r1) + stw r10,_UC_GREGS+(PT_R10*4)(r3) + beq 2f /* if exactly 8 args */ + subi r9,r5,3 + subi r5,r5,8 + rlwinm r9,r9,2,0,27 + subf r7,r9,r4 + mtctr r5 /* copy the 9th and following args */ + addi r6,r1,16 + addi r8,r7,4 +3: lwzu r10,4(r6) + stwu r10,4(r8) + bdnz 3b +2: stw r7,_UC_GREGS+(PT_R1*4)(r3) + li r6,0 + stw r6,0(r7) + + blr + +/* + * If the function returns, it comes here. We put ucp->uc_link in + * r31, which is a callee-saved register. We have to continue with + * the context that r31 points to, or exit if it is 0. + */ +L(exitcode): + mr. r3,r31 + beq 4f + bl JUMPTARGET(__setcontext) +4: bl HIDDEN_JUMPTARGET(exit) + b 4b + +END(__makecontext) +weak_alias(__makecontext, makecontext) |