/*--------------------------------------------------------------------*/ /*--- The core dispatch loop, for jumping to a code address. ---*/ /*--- dispatch-s390x-linux.S ---*/ /*--------------------------------------------------------------------*/ /* This file is part of Valgrind, a dynamic binary instrumentation framework. Copyright IBM Corp. 2010-2017 Copyright (C) 2011-2017, Florian Krohm (britzel@acm.org) 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, see . The GNU General Public License is contained in the file COPYING. */ /* Contributed by Florian Krohm and Christian Borntraeger */ #include "pub_core_basics_asm.h" #include "pub_core_dispatch_asm.h" #include "pub_core_transtab_asm.h" #include "libvex_guest_offsets.h" #include "libvex_s390x_common.h" #if defined(VGA_s390x) /*------------------------------------------------------------*/ /*--- ---*/ /*--- The dispatch loop. VG_(disp_run_translations) is ---*/ /*--- used to run all translations, ---*/ /*--- including no-redir ones. ---*/ /*--- ---*/ /*------------------------------------------------------------*/ /* Convenience definitions for readability */ #undef SP #define SP S390_REGNO_STACK_POINTER #undef LR #define LR S390_REGNO_LINK_REGISTER /* Location of valgrind's saved FPC register */ #define S390_LOC_SAVED_FPC_V S390_OFFSET_SAVED_FPC_V(SP) /* Location of saved R2 register */ #define S390_LOC_SAVED_R2 S390_OFFSET_SAVED_R2(SP) /*----------------------------------------------------*/ /*--- Entry and preamble (set everything up) ---*/ /*----------------------------------------------------*/ /* signature: void VG_(disp_run_translations)( UWord* two_words, void* guest_state, Addr host_addr ); Return results are placed in two_words: two_words[0] is set to the TRC two_words[1] is set to the address to patch (in case two_words[0] is VG_TRC_CHAIN_ME_TO_{SLOW,FAST}_EP). Otherwise, it is 0. */ .text .align 4 .globl VG_(disp_run_translations) .type VG_(disp_run_translations), @function VG_(disp_run_translations): /* r2 holds two_words */ /* r3 holds pointer to guest_state */ /* r4 holds host_addr, i.e. the address of the translation to run */ /* Save gprs ABI: r6...r13 and r15 */ stmg %r6,%r15,48(SP) /* New stack frame */ aghi SP,-S390_INNERLOOP_FRAME_SIZE /* Save fprs: ABI: f8...f15 */ std %f8,160+0(SP) std %f9,160+8(SP) std %f10,160+16(SP) std %f11,160+24(SP) std %f12,160+32(SP) std %f13,160+40(SP) std %f14,160+48(SP) std %f15,160+56(SP) /* Load address of guest state into guest state register (r13) */ lgr %r13,%r3 /* Save R2 on stack. In postamble it will be restored such that the return values can be written */ stg %r2,S390_LOC_SAVED_R2 /* Save valgrind's FPC on stack so postamble can restore it later . */ stfpc S390_LOC_SAVED_FPC_V /* Load the FPC the way the client code wants it. I.e. pull the value from the guest state. */ lfpc OFFSET_s390x_fpc(%r13) /* 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. */ br %r4 /*----------------------------------------------------*/ /*--- Postamble and return to C code. ---*/ /*----------------------------------------------------*/ postamble: /* At this point, %r0 and %r1 contain two words to be returned to the caller. %r0 holds a TRC value, and %r1 optionally may hold another word (for CHAIN_ME exits, the address of the place to patch.) */ /* We're leaving. AMD has some code here to check invariants. We don't have (need) that, as we save and restore the FPC register whenever we switch between valgrind proper to client code. */ /* Restore valgrind's FPC, as client code may have changed it. */ lfpc S390_LOC_SAVED_FPC_V /* Restore %r2 from stack; holds address of two_words */ lg %r2,S390_LOC_SAVED_R2 stg %r0,0(%r2) /* Store %r0 to two_words[0] */ stg %r1,8(%r2) /* Store %r1 to two_words[1] */ /* Restore callee-saved registers... */ /* Floating-point regs */ ld %f8,160+0(SP) ld %f9,160+8(SP) ld %f10,160+16(SP) ld %f11,160+24(SP) ld %f12,160+32(SP) ld %f13,160+40(SP) ld %f14,160+48(SP) ld %f15,160+56(SP) /* Remove stack frame */ aghi SP,S390_INNERLOOP_FRAME_SIZE /* General-purpose regs. This also restores the original link register (r14) and stack pointer (r15). */ lmg %r6,%r15,48(SP) /* Return */ br LR /*----------------------------------------------------*/ /*--- Continuation points ---*/ /*----------------------------------------------------*/ /* ------ Chain me to slow entry point ------ */ .global VG_(disp_cp_chain_me_to_slowEP) VG_(disp_cp_chain_me_to_slowEP): /* When we come here %r1 contains the address of the place to patch. The return values (TRC, address-to-patch) are stored here in %r0 and %r1, respectively */ lghi %r0,VG_TRC_CHAIN_ME_TO_SLOW_EP j postamble /* ------ Chain me to fast entry point ------ */ .global VG_(disp_cp_chain_me_to_fastEP) VG_(disp_cp_chain_me_to_fastEP): /* Identical to VG_(disp_cp_chain_me_to_slowEP), except value of %r0. */ lghi %r0,VG_TRC_CHAIN_ME_TO_FAST_EP j postamble /* ------ Indirect but boring jump ------ */ .global VG_(disp_cp_xindir) VG_(disp_cp_xindir): /* Where are we going? */ lg %r6, OFFSET_s390x_IA(%r13) // "guest" /* stats only */ larl %r11, VG_(stats__n_xIndirs_32) l %r12, 0(%r11) ahi %r12, 1 st %r12, 0(%r11) // LIVE: r13 (guest state ptr), r6 (guest address to go to). // We use 6 temporaries: // r7 (to point at the relevant FastCacheSet), // r8, r9, r10 (scratch, for swapping entries within a set) // r11, r12 (other scratch) /* Try a fast lookup in the translation cache. This is pretty much a handcoded version of VG_(lookupInFastCache). */ // Compute %r7 = VG_TT_FAST_HASH(guest) srlg %r7, %r6, 1 // g1 = guest >> 1 srlg %r8, %r6, (VG_TT_FAST_BITS + 1) // (g1 >> VG_TT_FAST_BITS) xgr %r7, %r8 // (g1 >> VG_TT_FAST_BITS) ^ g1 llill %r8, VG_TT_FAST_MASK & 0xffff # if ((VG_TT_FAST_MASK & 0xffff0000) >> 16 != 0) iilh %r8, (VG_TT_FAST_MASK & 0xffff0000) >> 16 # endif ngr %r7, %r8 // setNo // Compute %r7 = &VG_(tt_fast)[%r7] sllg %r7,%r7, VG_FAST_CACHE_SET_BITS // setNo * sizeof(FastCacheSet) larl %r8, VG_(tt_fast) // &VG_(tt_fast)[0] agr %r7, %r8 // &VG_(tt_fast)[setNo] // LIVE: %r13 (guest state ptr), %r6 (guest addr), %r7 (cache set) // try way 0 cg %r6, FCS_g0(%r7) // cmp against .guest0 lg %r8, FCS_h0(%r7) jne 1f // hit at way 0 // goto .host0 br %r8 /*NOTREACHED*/ .long 0 1: // try way 1 cg %r6, FCS_g1(%r7) // cmp against .guest1 jne 2f // hit at way 1; swap upwards lg %r8, FCS_g0(%r7) // r8 = old .guest0 lg %r9, FCS_h0(%r7) // r9 = old .host0 lg %r10, FCS_h1(%r7) // r10 = old .host1 stg %r6, FCS_g0(%r7) // new .guest0 = guest stg %r10, FCS_h0(%r7) // new .host0 = old .host1 stg %r8, FCS_g1(%r7) // new .guest1 = old .guest0 stg %r9, FCS_h1(%r7) // new .host1 = old .host0 // stats only larl %r11, VG_(stats__n_xIndir_hits1_32) l %r12, 0(%r11) ahi %r12, 1 st %r12, 0(%r11) // goto old .host1 a.k.a. new .host0 br %r10 /*NOTREACHED*/ .long 0 2: // try way 2 cg %r6, FCS_g2(%r7) // cmp against .guest2 jne 3f lg %r8, FCS_g1(%r7) lg %r9, FCS_h1(%r7) lg %r10, FCS_h2(%r7) stg %r6, FCS_g1(%r7) stg %r10, FCS_h1(%r7) stg %r8, FCS_g2(%r7) stg %r9, FCS_h2(%r7) // stats only larl %r11, VG_(stats__n_xIndir_hits2_32) l %r12, 0(%r11) ahi %r12, 1 st %r12, 0(%r11) // goto old .host2 a.k.a. new .host1 br %r10 /*NOTREACHED*/ .long 0 3: // try way 3 cg %r6, FCS_g3(%r7) // cmp against .guest3 jne 4f // hit at way 3; swap upwards lg %r8, FCS_g2(%r7) lg %r9, FCS_h2(%r7) lg %r10, FCS_h3(%r7) stg %r6, FCS_g2(%r7) stg %r10, FCS_h2(%r7) stg %r8, FCS_g3(%r7) stg %r9, FCS_h3(%r7) // stats only larl %r11, VG_(stats__n_xIndir_hits3_32) l %r12, 0(%r11) ahi %r12, 1 st %r12, 0(%r11) // goto old .host3 a.k.a. new .host2 br %r10 .long 0 4: // fast lookup failed larl %r11, VG_(stats__n_xIndir_misses_32) l %r12, 0(%r11) ahi %r12, 1 st %r12, 0(%r11) lghi %r0, VG_TRC_INNER_FASTMISS lghi %r1, 0 j postamble /*NOTREACHED*/ /* ------ Assisted jump ------ */ .global VG_(disp_cp_xassisted) VG_(disp_cp_xassisted): /* guest-state-pointer contains the TRC. Put the value into the return register */ lgr %r0,%r13 lghi %r1,0 j postamble /* ------ Event check failed ------ */ .global VG_(disp_cp_evcheck_fail) VG_(disp_cp_evcheck_fail): lghi %r0,VG_TRC_INNER_COUNTERZERO lghi %r1,0 j postamble .size VG_(disp_run_translations), .-VG_(disp_run_translations) #endif /* VGA_s390x */ /* Let the linker know we don't need an executable stack */ MARK_STACK_NO_EXEC /*--------------------------------------------------------------------*/ /*--- end dispatch-s390x-linux.S ---*/ /*--------------------------------------------------------------------*/