/*--------------------------------------------------------------------*/ /*--- The core dispatch loop, for jumping to a code address. ---*/ /*--- dispatch-ppc32-linux.S ---*/ /*--------------------------------------------------------------------*/ /* This file is part of Valgrind, a dynamic binary instrumentation framework. Copyright (C) 2005-2017 Cerion Armour-Brown <cerion@open-works.co.uk> This program 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 of the License, or (at your option) any later version. This program 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; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. The GNU General Public License is contained in the file COPYING. */ #include "pub_core_basics_asm.h" #if defined(VGP_ppc32_linux) #include "pub_core_dispatch_asm.h" #include "pub_core_transtab_asm.h" #include "libvex_guest_offsets.h" /* for OFFSET_ppc32_CIA */ /*------------------------------------------------------------*/ /*--- ---*/ /*--- The dispatch loop. VG_(disp_run_translations) is ---*/ /*--- used to run all translations, ---*/ /*--- including no-redir ones. ---*/ /*--- ---*/ /*------------------------------------------------------------*/ /*----------------------------------------------------*/ /*--- Entry and preamble (set everything up) ---*/ /*----------------------------------------------------*/ /* signature: void VG_(disp_run_translations)( UWord* two_words, void* guest_state, Addr host_addr ); */ .text .globl VG_(disp_run_translations) .type VG_(disp_run_translations), @function VG_(disp_run_translations): /* r3 holds two_words */ /* r4 holds guest_state */ /* r5 holds host_addr */ /* ----- entry point to VG_(disp_run_translations) ----- */ /* For Linux/ppc32 we need the SysV ABI, which uses LR->4(parent_sp), CR->anywhere. (The AIX ABI, used on Darwin, uses LR->8(prt_sp), CR->4(prt_sp)) */ /* Save lr */ mflr 6 stw 6,4(1) /* New stack frame */ stwu 1,-496(1) /* sp should maintain 16-byte alignment */ /* Save callee-saved registers... */ /* r3, r4, r5 are live here, so use r6 */ lis 6,VG_(machine_ppc32_has_FP)@ha lwz 6,VG_(machine_ppc32_has_FP)@l(6) cmplwi 6,0 beq LafterFP1 /* Floating-point reg save area : 144 bytes */ stfd 31,488(1) stfd 30,480(1) stfd 29,472(1) stfd 28,464(1) stfd 27,456(1) stfd 26,448(1) stfd 25,440(1) stfd 24,432(1) stfd 23,424(1) stfd 22,416(1) stfd 21,408(1) stfd 20,400(1) stfd 19,392(1) stfd 18,384(1) stfd 17,376(1) stfd 16,368(1) stfd 15,360(1) stfd 14,352(1) LafterFP1: /* General reg save area : 76 bytes */ stw 31,348(1) stw 30,344(1) stw 29,340(1) stw 28,336(1) stw 27,332(1) stw 26,328(1) stw 25,324(1) stw 24,320(1) stw 23,316(1) stw 22,312(1) stw 21,308(1) stw 20,304(1) stw 19,300(1) stw 18,296(1) stw 17,292(1) stw 16,288(1) stw 15,284(1) stw 14,280(1) stw 13,276(1) stw 3,272(1) /* save two_words for later */ /* It's necessary to save/restore VRSAVE in the AIX / Darwin ABI. The Linux kernel might not actually use VRSAVE for its intended purpose, but it should be harmless to preserve anyway. */ /* r3, r4, r5 are live here, so use r6 */ lis 6,VG_(machine_ppc32_has_VMX)@ha lwz 6,VG_(machine_ppc32_has_VMX)@l(6) cmplwi 6,0 beq LafterVMX1 #ifdef HAS_ALTIVEC /* VRSAVE save word : 32 bytes */ mfspr 6,256 /* vrsave reg is spr number 256 */ stw 6,244(1) /* Alignment padding : 4 bytes */ /* Vector reg save area (quadword aligned) : 192 bytes */ li 6,224 stvx 31,6,1 li 6,208 stvx 30,6,1 li 6,192 stvx 29,6,1 li 6,176 stvx 28,6,1 li 6,160 stvx 27,6,1 li 6,144 stvx 26,6,1 li 6,128 stvx 25,6,1 li 6,112 stvx 24,6,1 li 6,96 stvx 23,6,1 li 6,80 stvx 22,6,1 li 6,64 stvx 21,6,1 li 6,48 stvx 20,6,1 #endif LafterVMX1: /* Save cr */ mfcr 6 stw 6,44(1) /* Local variable space... */ /* 32(sp) used later to check FPSCR[RM] */ /* r3 holds two_words */ /* r4 holds guest_state */ /* r5 holds host_addr */ /* 24(sp) used later to stop ctr reg being clobbered */ /* 20(sp) used later to load fpscr with zero */ /* 8:16(sp) free */ /* Linkage Area (reserved) 4(sp) : LR 0(sp) : back-chain */ /* set host FPU control word to the default mode expected by VEX-generated code. See comments in libvex.h for more info. */ lis 6,VG_(machine_ppc32_has_FP)@ha lwz 6,VG_(machine_ppc32_has_FP)@l(6) cmplwi 6,0 beq LafterFP2 /* get zero into f3 (tedious) */ /* note: fsub 3,3,3 is not a reliable way to do this, since if f3 holds a NaN or similar then we don't necessarily wind up with zero. */ li 6,0 stw 6,20(1) lfs 3,20(1) mtfsf 0xFF,3 /* fpscr = f3 */ LafterFP2: /* set host AltiVec control word to the default mode expected by VEX-generated code. */ lis 6,VG_(machine_ppc32_has_VMX)@ha lwz 6,VG_(machine_ppc32_has_VMX)@l(6) cmplwi 6,0 beq LafterVMX2 #ifdef HAS_ALTIVEC vspltisw 3,0x0 /* generate zero */ mtvscr 3 #endif LafterVMX2: /* make a stack frame for the code we are calling */ stwu 1,-16(1) /* Set up the guest state ptr */ mr 31,4 /* r31 (generated code gsp) = r4 */ /* and jump into the code cache. Chained translations in the code cache run, until for whatever reason, they can't continue. When that happens, the translation in question will jump (or call) to one of the continuation points VG_(cp_...) below. */ mtctr 5 bctr /*NOTREACHED*/ /*----------------------------------------------------*/ /*--- Postamble and exit. ---*/ /*----------------------------------------------------*/ postamble: /* At this point, r6 and r7 contain two words to be returned to the caller. r6 holds a TRC value, and r7 optionally may hold another word (for CHAIN_ME exits, the address of the place to patch.) */ /* We're leaving. Check that nobody messed with VSCR or FPSCR in ways we don't expect. */ /* Using r10 - value used again further on, so don't trash! */ lis 10,VG_(machine_ppc32_has_FP)@ha lwz 10,VG_(machine_ppc32_has_FP)@l(10) /* Using r11 - value used again further on, so don't trash! */ lis 11,VG_(machine_ppc32_has_VMX)@ha lwz 11,VG_(machine_ppc32_has_VMX)@l(11) cmplwi 10,0 /* Do we have FP ? */ beq LafterFP8 /* Set fpscr back to a known state, since vex-generated code may have messed with fpscr[rm]. */ li 5,0 addi 1,1,-16 stw 5,0(1) lfs 3,0(1) addi 1,1,16 mtfsf 0xFF,3 /* fpscr = f3 */ LafterFP8: cmplwi 11,0 /* Do we have altivec? */ beq LafterVMX8 #ifdef HAS_ALTIVEC /* Check VSCR[NJ] == 1 */ /* first generate 4x 0x00010000 */ vspltisw 4,0x1 /* 4x 0x00000001 */ vspltisw 5,0x0 /* zero */ vsldoi 6,4,5,0x2 /* <<2*8 => 4x 0x00010000 */ /* retrieve VSCR and mask wanted bits */ mfvscr 7 vand 7,7,6 /* gives NJ flag */ vspltw 7,7,0x3 /* flags-word to all lanes */ vcmpequw. 8,6,7 /* CR[24] = 1 if v6 == v7 */ bt 24,invariant_violation /* branch if all_equal */ #endif LafterVMX8: /* otherwise we're OK */ b remove_frame invariant_violation: li 6,VG_TRC_INVARIANT_FAILED li 7,0 /* fall through */ remove_frame: /* Restore FP regs */ /* r10 already holds VG_(machine_ppc32_has_FP) value */ cmplwi 10,0 beq LafterFP9 /* Floating-point regs */ lfd 31,488(1) lfd 30,480(1) lfd 29,472(1) lfd 28,464(1) lfd 27,456(1) lfd 26,448(1) lfd 25,440(1) lfd 24,432(1) lfd 23,424(1) lfd 22,416(1) lfd 21,408(1) lfd 20,400(1) lfd 19,392(1) lfd 18,384(1) lfd 17,376(1) lfd 16,368(1) lfd 15,360(1) lfd 14,352(1) LafterFP9: /* r11 already holds VG_(machine_ppc32_has_VMX) value */ cmplwi 11,0 beq LafterVMX9 /* Restore Altivec regs */ #ifdef HAS_ALTIVEC /* VRSAVE */ lwz 4,244(1) mfspr 4,256 /* VRSAVE reg is spr number 256 */ /* Vector regs */ li 4,224 lvx 31,4,1 li 4,208 lvx 30,4,1 li 4,192 lvx 29,4,1 li 4,176 lvx 28,4,1 li 4,160 lvx 27,4,1 li 4,144 lvx 26,4,1 li 4,128 lvx 25,4,1 li 4,112 lvx 24,4,1 li 4,96 lvx 23,4,1 li 4,80 lvx 22,4,1 li 4,64 lvx 21,4,1 li 4,48 lvx 20,4,1 #endif LafterVMX9: /* restore int regs, including importantly r3 (two_words) */ addi 1,1,16 lwz 31,348(1) lwz 30,344(1) lwz 29,340(1) lwz 28,336(1) lwz 27,332(1) lwz 26,328(1) lwz 25,324(1) lwz 24,320(1) lwz 23,316(1) lwz 22,312(1) lwz 21,308(1) lwz 20,304(1) lwz 19,300(1) lwz 18,296(1) lwz 17,292(1) lwz 16,288(1) lwz 15,284(1) lwz 14,280(1) lwz 13,276(1) lwz 3,272(1) /* Stash return values */ stw 6,0(3) stw 7,4(3) /* restore lr & sp, and leave */ lwz 0,500(1) /* stack_size + 4 */ mtlr 0 addi 1,1,496 /* stack_size */ blr /*----------------------------------------------------*/ /*--- Continuation points ---*/ /*----------------------------------------------------*/ /* ------ Chain me to slow entry point ------ */ .global VG_(disp_cp_chain_me_to_slowEP) VG_(disp_cp_chain_me_to_slowEP): /* We got called. The return address indicates where the patching needs to happen. Collect the return address and, exit back to C land, handing the caller the pair (Chain_me_S, RA) */ li 6, VG_TRC_CHAIN_ME_TO_SLOW_EP mflr 7 /* 8 = imm32-fixed2 r30, disp_cp_chain_me_to_slowEP 4 = mtctr r30 4 = btctr */ subi 7,7,8+4+4 b postamble /* ------ Chain me to fast entry point ------ */ .global VG_(disp_cp_chain_me_to_fastEP) VG_(disp_cp_chain_me_to_fastEP): /* We got called. The return address indicates where the patching needs to happen. Collect the return address and, exit back to C land, handing the caller the pair (Chain_me_S, RA) */ li 6, VG_TRC_CHAIN_ME_TO_FAST_EP mflr 7 /* 8 = imm32-fixed2 r30, disp_cp_chain_me_to_fastEP 4 = mtctr r30 4 = btctr */ subi 7,7,8+4+4 b postamble /* ------ Indirect but boring jump ------ */ .global VG_(disp_cp_xindir) VG_(disp_cp_xindir): /* Where are we going? */ lwz 3,OFFSET_ppc32_CIA(31) /* stats only */ lis 5,VG_(stats__n_xindirs_32)@ha addi 5,5,VG_(stats__n_xindirs_32)@l lwz 6,0(5) addi 6,6,1 stw 6,0(5) /* r5 = &VG_(tt_fast) */ lis 5,VG_(tt_fast)@ha addi 5,5,VG_(tt_fast)@l /* & VG_(tt_fast) */ /* try a fast lookup in the translation cache */ /* r4 = VG_TT_FAST_HASH(addr) * sizeof(FastCacheEntry) = ((r3 >>u 2) & VG_TT_FAST_MASK) << 3 */ rlwinm 4,3,1, 29-VG_TT_FAST_BITS, 28 /* entry# * 8 */ add 5,5,4 /* & VG_(tt_fast)[entry#] */ lwz 6,0(5) /* .guest */ lwz 7,4(5) /* .host */ cmpw 3,6 bne fast_lookup_failed /* Found a match. Jump to .host. */ mtctr 7 bctr fast_lookup_failed: /* stats only */ lis 5,VG_(stats__n_xindir_misses_32)@ha addi 5,5,VG_(stats__n_xindir_misses_32)@l lwz 6,0(5) addi 6,6,1 stw 6,0(5) li 6,VG_TRC_INNER_FASTMISS li 7,0 b postamble /*NOTREACHED*/ /* ------ Assisted jump ------ */ .global VG_(disp_cp_xassisted) VG_(disp_cp_xassisted): /* r31 contains the TRC */ mr 6,31 li 7,0 b postamble /* ------ Event check failed ------ */ .global VG_(disp_cp_evcheck_fail) VG_(disp_cp_evcheck_fail): li 6,VG_TRC_INNER_COUNTERZERO li 7,0 b postamble .size VG_(disp_run_translations), .-VG_(disp_run_translations) #endif // defined(VGP_ppc32_linux) /* Let the linker know we don't need an executable stack */ MARK_STACK_NO_EXEC /*--------------------------------------------------------------------*/ /*--- end ---*/ /*--------------------------------------------------------------------*/