/* 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) 2004-2024 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 3, or (at your option) any * later version. * * 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. * * Under Section 7 of GPL version 3, you are granted additional * permissions described in the GCC Runtime Library Exception, version * 3.1, as published by the Free Software Foundation. * * You should have received a copy of the GNU General Public License and * a copy of the GCC Runtime Library Exception along with this program; * see the files COPYING3 and COPYING.RUNTIME respectively. If not, see * . */ #ifndef __ppc64__ .machine ppc7400 .data .align 2 #ifdef __DYNAMIC__ .non_lazy_symbol_pointer L_has_vec$non_lazy_ptr: .indirect_symbol __cpu_has_altivec .long 0 #else /* For static, "pretend" we have a non-lazy-pointer. */ L_has_vec$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 the updated VRsave in R0 if we`re on a CPU with vector regs. For gcc3 onward, we need to save and restore CR as well, since 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 stw r0,0(r12) /* VRsave lives at -224(R1). */ ori r0,r0,0xfff /* We just saved these. */ mtspr VRsave,r0 blr /* rest_world is jumped to, not called, so no need to worry about LR. clobbers R0, R7, R11 and R12. This just undoes the work done above. */ .private_extern rest_world rest_world: lwz r11, 0(r1) /* Pickup previous SP */ li r7, 0 /* Stack offset is zero, r10 is ignored. */ b Lrest_world_eh_r7 /* 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. clobbers: R0, R7, R11 and R12 uses : R10 RETURNS : C++ EH Data registers (R3 - R6). */ .private_extern eh_rest_world_r10 eh_rest_world_r10: lwz r11, 0(r1) /* Pickup previous SP */ mr r7,r10 /* Stack offset. */ /* pickup the C++ EH data regs (R3 - R6.) */ lwz r6,-420(r11) lwz r5,-424(r11) lwz r4,-428(r11) lwz r3,-432(r11) /* Fall through to Lrest_world_eh_r7. */ /* When we are doing the exception-handling epilog, R7 contains the offset to add to the SP. clobbers: R0, R11 and R12 uses : R7. */ Lrest_world_eh_r7: /* See if we have Altivec. */ bcl 20,31,Lr7$pb Lr7$pb: mflr r12 addis r12,r12,ha16(L_has_vec$non_lazy_ptr-Lr7$pb) lwz r12,lo16(L_has_vec$non_lazy_ptr-Lr7$pb)(r12) lwz r12,0(r12) /* R12 := HAS_VEC */ cmpwi r12,0 lmw r13,-220(r11) beq L.rest_world_fp_eh /* We have Altivec, 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: lwz r0,4(r11) /* recover saved CR */ 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) mtcr r0 /* restore the saved cr. */ lwz r0, 8(r11) /* Pick up the 'real' return address. */ lfd f31,-8(r11) mtctr r0 /* exception-handler ret. address */ add r1,r11,r7 /* set SP to original value + R7 offset */ bctr #endif /* we should never be called on ppc64 for this ... */ /* Done. */