/* This file contains the exception-handling save_world and * restore_world routines, which need to do a run-time check to see if * they should save and restore the vector registers. * * Copyright (C) 2004 Free Software Foundation, Inc. * * This file is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2, or (at your option) any * later version. * * In addition to the permissions in the GNU General Public License, the * Free Software Foundation gives you unlimited permission to link the * compiled version of this file with other programs, and to distribute * those programs without any restriction coming from the use of this * file. (The General Public License restrictions do apply in other * respects; for example, they cover modification of the file, and * distribution when not linked into another program.) * * This file 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 * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; see the file COPYING. If not, write to * the Free Software Foundation, 51 Franklin Street, Fifth Floor, * Boston, MA 02110-1301, USA. * * As a special exception, if you link this library with files * compiled with GCC to produce an executable, this does not cause the * resulting executable to be covered by the GNU General Public License. * This exception does not however invalidate any other reasons why the * executable file might be covered by the GNU General Public License. */ .machine ppc7400 .data .align 2 #ifdef __DYNAMIC__ .non_lazy_symbol_pointer L_has_vec$non_lazy_ptr: .indirect_symbol __cpu_has_altivec #ifdef __ppc64__ .quad 0 #else .long 0 #endif #else /* For static, "pretend" we have a non-lazy-pointer. */ L_has_vec$non_lazy_ptr: .long __cpu_has_altivec #endif .text .align 2 /* save_world and rest_world save/restore F14-F31 and possibly V20-V31 (assuming you have a CPU with vector registers; we use a global var provided by the System Framework to determine this.) SAVE_WORLD takes R0 (the caller`s caller`s return address) and R11 (the stack frame size) as parameters. It returns VRsave in R0 if we`re on a CPU with vector regs. With gcc3, we now need to save and restore CR as well, since gcc3's scheduled prologs can cause comparisons to be moved before calls to save_world! USES: R0 R11 R12 */ .private_extern save_world save_world: stw r0,8(r1) mflr r0 bcl 20,31,Ls$pb Ls$pb: mflr r12 addis r12,r12,ha16(L_has_vec$non_lazy_ptr-Ls$pb) lwz r12,lo16(L_has_vec$non_lazy_ptr-Ls$pb)(r12) mtlr r0 lwz r12,0(r12) /* grab CR */ mfcr r0 /* test HAS_VEC */ cmpwi r12,0 stfd f14,-144(r1) stfd f15,-136(r1) stfd f16,-128(r1) stfd f17,-120(r1) stfd f18,-112(r1) stfd f19,-104(r1) stfd f20,-96(r1) stfd f21,-88(r1) stfd f22,-80(r1) stfd f23,-72(r1) stfd f24,-64(r1) stfd f25,-56(r1) stfd f26,-48(r1) stfd f27,-40(r1) stfd f28,-32(r1) stfd f29,-24(r1) stfd f30,-16(r1) stfd f31,-8(r1) stmw r13,-220(r1) /* stash CR */ stw r0,4(r1) /* set R12 pointing at Vector Reg save area */ addi r12,r1,-224 /* allocate stack frame */ stwux r1,r1,r11 /* ...but return if HAS_VEC is zero */ bne+ L$saveVMX /* Not forgetting to restore CR. */ mtcr r0 blr L$saveVMX: /* We're saving Vector regs too. */ /* Restore CR from R0. No More Branches! */ mtcr r0 /* We should really use VRSAVE to figure out which vector regs we actually need to save and restore. Some other time :-/ */ li r11,-192 stvx v20,r11,r12 li r11,-176 stvx v21,r11,r12 li r11,-160 stvx v22,r11,r12 li r11,-144 stvx v23,r11,r12 li r11,-128 stvx v24,r11,r12 li r11,-112 stvx v25,r11,r12 li r11,-96 stvx v26,r11,r12 li r11,-80 stvx v27,r11,r12 li r11,-64 stvx v28,r11,r12 li r11,-48 stvx v29,r11,r12 li r11,-32 stvx v30,r11,r12 mfspr r0,VRsave li r11,-16 stvx v31,r11,r12 /* VRsave lives at -224(R1) */ stw r0,0(r12) blr /* eh_rest_world_r10 is jumped to, not called, so no need to worry about LR. R10 is the C++ EH stack adjust parameter, we return to the caller`s caller. USES: R0 R10 R11 R12 and R7 R8 RETURNS: C++ EH Data registers (R3 - R6.) We now set up R7/R8 and jump to rest_world_eh_r7r8. rest_world doesn't use the R10 stack adjust parameter, nor does it pick up the R3-R6 exception handling stuff. */ .private_extern rest_world rest_world: /* Pickup previous SP */ lwz r11, 0(r1) li r7, 0 lwz r8, 8(r11) li r10, 0 b rest_world_eh_r7r8 .private_extern eh_rest_world_r10 eh_rest_world_r10: /* Pickup previous SP */ lwz r11, 0(r1) mr r7,r10 lwz r8, 8(r11) /* pickup the C++ EH data regs (R3 - R6.) */ lwz r6,-420(r11) lwz r5,-424(r11) lwz r4,-428(r11) lwz r3,-432(r11) b rest_world_eh_r7r8 /* rest_world_eh_r7r8 is jumped to -- not called! -- when we're doing the exception-handling epilog. R7 contains the offset to add to the SP, and R8 contains the 'real' return address. USES: R0 R11 R12 [R7/R8] RETURNS: C++ EH Data registers (R3 - R6.) */ rest_world_eh_r7r8: bcl 20,31,Lr7r8$pb Lr7r8$pb: mflr r12 lwz r11,0(r1) /* R11 := previous SP */ addis r12,r12,ha16(L_has_vec$non_lazy_ptr-Lr7r8$pb) lwz r12,lo16(L_has_vec$non_lazy_ptr-Lr7r8$pb)(r12) lwz r0,4(r11) /* R0 := old CR */ lwz r12,0(r12) /* R12 := HAS_VEC */ mtcr r0 cmpwi r12,0 lmw r13,-220(r11) beq L.rest_world_fp_eh /* restore VRsave and V20..V31 */ lwz r0,-224(r11) li r12,-416 mtspr VRsave,r0 lvx v20,r11,r12 li r12,-400 lvx v21,r11,r12 li r12,-384 lvx v22,r11,r12 li r12,-368 lvx v23,r11,r12 li r12,-352 lvx v24,r11,r12 li r12,-336 lvx v25,r11,r12 li r12,-320 lvx v26,r11,r12 li r12,-304 lvx v27,r11,r12 li r12,-288 lvx v28,r11,r12 li r12,-272 lvx v29,r11,r12 li r12,-256 lvx v30,r11,r12 li r12,-240 lvx v31,r11,r12 L.rest_world_fp_eh: lfd f14,-144(r11) lfd f15,-136(r11) lfd f16,-128(r11) lfd f17,-120(r11) lfd f18,-112(r11) lfd f19,-104(r11) lfd f20,-96(r11) lfd f21,-88(r11) lfd f22,-80(r11) lfd f23,-72(r11) lfd f24,-64(r11) lfd f25,-56(r11) lfd f26,-48(r11) lfd f27,-40(r11) lfd f28,-32(r11) lfd f29,-24(r11) lfd f30,-16(r11) /* R8 is the exception-handler's address */ mtctr r8 lfd f31,-8(r11) /* set SP to original value + R7 offset */ add r1,r11,r7 bctr