| |
| /*--------------------------------------------------------------------*/ |
| /*--- The JITter proper: register allocation & code improvement ---*/ |
| /*--- vg_translate.c ---*/ |
| /*--------------------------------------------------------------------*/ |
| |
| /* |
| This file is part of Valgrind, an extensible x86 protected-mode |
| emulator for monitoring program execution on x86-Unixes. |
| |
| Copyright (C) 2000-2004 Julian Seward |
| jseward@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, 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 "core.h" |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- %SP-update pass ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* NOTE: this comment is out of date */ |
| |
| /* For tools that want to know about %ESP changes, this pass adds |
| in the appropriate hooks. We have to do it after the tool's |
| instrumentation, so the tool doesn't have to worry about the CCALLs |
| it adds in, and we must do it before register allocation because |
| spilled temps make it much harder to work out the %esp deltas. |
| Thus we have it as an extra phase between the two. |
| |
| We look for "GETL %ESP, t_ESP", then track ADDs and SUBs of |
| literal values to t_ESP, and the total delta of the ADDs/SUBs. Then if |
| "PUTL t_ESP, %ESP" happens, we call the helper with the known delta. We |
| also cope with "MOVL t_ESP, tX", making tX the new t_ESP. If any other |
| instruction clobbers t_ESP, we don't track it anymore, and fall back to |
| the delta-is-unknown case. That case is also used when the delta is not |
| a nice small amount, or an unknown amount. |
| */ |
| |
| static |
| IRBB* vg_SP_update_pass ( IRBB* bb_in, VexGuestLayout* layout, |
| IRType hWordTy ) |
| { |
| Int i, j, minoff_ST, maxoff_ST; |
| IRDirty *dcall, *d; |
| IRStmt* st; |
| IRExpr* e; |
| IRArray* descr; |
| |
| /* Set up BB */ |
| IRBB* bb = emptyIRBB(); |
| bb->tyenv = dopyIRTypeEnv(bb_in->tyenv); |
| bb->next = dopyIRExpr(bb_in->next); |
| bb->jumpkind = bb_in->jumpkind; |
| |
| IRTemp curr = IRTemp_INVALID; |
| Long delta = 0; |
| |
| Int sizeof_SP = layout->sizeof_SP; |
| Int offset_SP = layout->offset_SP; |
| IRType typeof_SP = sizeof_SP==4 ? Ity_I32 : Ity_I64; |
| vg_assert(sizeof_SP == 4 || sizeof_SP == 8); |
| |
| # define IS_ADD(op) (sizeof_SP==4 ? ((op)==Iop_Add32) : ((op)==Iop_Add64)) |
| # define IS_SUB(op) (sizeof_SP==4 ? ((op)==Iop_Sub32) : ((op)==Iop_Sub64)) |
| |
| # define IS_ADD_OR_SUB(op) (IS_ADD(op) || IS_SUB(op)) |
| |
| # define GET_CONST(con) \ |
| (sizeof_SP==4 ? (Long)(Int)(con->Ico.U32) \ |
| : (Long)(con->Ico.U64)) |
| |
| # define DO(kind, syze) \ |
| do { \ |
| if (!VG_(defined_##kind##_mem_stack_##syze)()) \ |
| goto generic; \ |
| \ |
| /* I don't know if it's really necessary to say that the */ \ |
| /* call reads the stack pointer. But anyway, we do. */ \ |
| dcall = unsafeIRDirty_0_N( \ |
| 1/*regparms*/, \ |
| "track_" #kind "_mem_stack_" #syze, \ |
| VG_(tool_interface) \ |
| .track_##kind##_mem_stack_##syze, \ |
| mkIRExprVec_1(IRExpr_Tmp(curr)) \ |
| ); \ |
| dcall->nFxState = 1; \ |
| dcall->fxState[0].fx = Ifx_Read; \ |
| dcall->fxState[0].offset = layout->offset_SP; \ |
| dcall->fxState[0].size = layout->sizeof_SP; \ |
| \ |
| addStmtToIRBB( bb, IRStmt_Dirty(dcall) ); \ |
| } while (0) |
| |
| for (i = 0; i < bb_in->stmts_used; i++) { |
| |
| st = bb_in->stmts[i]; |
| if (!st) |
| continue; |
| |
| /* t = Get(sp): curr = t, delta = 0 */ |
| if (st->tag != Ist_Tmp) goto case2; |
| e = st->Ist.Tmp.data; |
| if (e->tag != Iex_Get) goto case2; |
| if (e->Iex.Get.offset != offset_SP) goto case2; |
| if (e->Iex.Get.ty != typeof_SP) goto case2; |
| curr = st->Ist.Tmp.tmp; |
| delta = 0; |
| addStmtToIRBB( bb, st ); |
| continue; |
| |
| case2: |
| /* t' = curr +/- const: curr = t', delta +=/-= const */ |
| if (st->tag != Ist_Tmp) goto case3; |
| e = st->Ist.Tmp.data; |
| if (e->tag != Iex_Binop) goto case3; |
| if (e->Iex.Binop.arg1->tag != Iex_Tmp) goto case3; |
| if (e->Iex.Binop.arg1->Iex.Tmp.tmp != curr) goto case3; |
| if (e->Iex.Binop.arg2->tag != Iex_Const) goto case3; |
| if (!IS_ADD_OR_SUB(e->Iex.Binop.op)) goto case3; |
| curr = st->Ist.Tmp.tmp; |
| if (IS_ADD(e->Iex.Binop.op)) |
| delta += GET_CONST(e->Iex.Binop.arg2->Iex.Const.con); |
| else |
| delta -= GET_CONST(e->Iex.Binop.arg2->Iex.Const.con); |
| addStmtToIRBB( bb, st ); |
| continue; |
| |
| case3: |
| /* t' = curr: curr = t' */ |
| if (st->tag != Ist_Tmp) goto case4; |
| e = st->Ist.Tmp.data; |
| if (e->tag != Iex_Tmp) goto case4; |
| if (e->Iex.Tmp.tmp != curr) goto case4; |
| curr = st->Ist.Tmp.tmp; |
| addStmtToIRBB( bb, st ); |
| continue; |
| |
| case4: |
| /* Put(sp) = curr */ |
| if (st->tag != Ist_Put) goto case5; |
| if (st->Ist.Put.offset != offset_SP) goto case5; |
| if (st->Ist.Put.data->tag != Iex_Tmp) goto case5; |
| if (st->Ist.Put.data->Iex.Tmp.tmp == curr) { |
| switch (delta) { |
| case 0: addStmtToIRBB(bb,st); delta = 0; continue; |
| case 4: DO(die, 4); addStmtToIRBB(bb,st); delta = 0; continue; |
| case -4: DO(new, 4); addStmtToIRBB(bb,st); delta = 0; continue; |
| case 8: DO(die, 8); addStmtToIRBB(bb,st); delta = 0; continue; |
| case -8: DO(new, 8); addStmtToIRBB(bb,st); delta = 0; continue; |
| case 12: DO(die, 12); addStmtToIRBB(bb,st); delta = 0; continue; |
| case -12: DO(new, 12); addStmtToIRBB(bb,st); delta = 0; continue; |
| case 16: DO(die, 16); addStmtToIRBB(bb,st); delta = 0; continue; |
| case -16: DO(new, 16); addStmtToIRBB(bb,st); delta = 0; continue; |
| case 32: DO(die, 32); addStmtToIRBB(bb,st); delta = 0; continue; |
| case -32: DO(new, 32); addStmtToIRBB(bb,st); delta = 0; continue; |
| default: goto generic; |
| } |
| } else { |
| generic: |
| /* I don't know if it's really necessary to say that the call |
| reads the stack pointer. But anyway, we do. */ |
| dcall = unsafeIRDirty_0_N( |
| 1/*regparms*/, |
| "VG_(unknown_SP_update)", &VG_(unknown_SP_update), |
| mkIRExprVec_1(st->Ist.Put.data) |
| ); |
| dcall->nFxState = 1; |
| dcall->fxState[0].fx = Ifx_Read; |
| dcall->fxState[0].offset = layout->offset_SP; |
| dcall->fxState[0].size = layout->sizeof_SP; |
| |
| addStmtToIRBB( bb, IRStmt_Dirty(dcall) ); |
| addStmtToIRBB(bb,st); |
| |
| curr = st->Ist.Put.data->Iex.Tmp.tmp; |
| delta = 0; |
| continue; |
| } |
| |
| case5: |
| /* PutI or Dirty call which overlaps SP: complain. We can't |
| deal with SP changing in weird ways (well, we can, but not at |
| this time of night). */ |
| if (st->tag == Ist_PutI) { |
| descr = st->Ist.PutI.descr; |
| minoff_ST = descr->base; |
| maxoff_ST = descr->base + descr->nElems * sizeofIRType(descr->elemTy) - 1; |
| if (!(offset_SP > maxoff_ST || (offset_SP + sizeof_SP - 1) < minoff_ST)) |
| goto complain; |
| } |
| if (st->tag == Ist_Dirty) { |
| d = st->Ist.Dirty.details; |
| for (j = 0; j < d->nFxState; j++) { |
| minoff_ST = d->fxState[j].offset; |
| maxoff_ST = d->fxState[j].offset + d->fxState[j].size - 1; |
| if (d->fxState[j].fx == Ifx_Read || d->fxState[j].fx == Ifx_None) |
| continue; |
| if (!(offset_SP > maxoff_ST || (offset_SP + sizeof_SP - 1) < minoff_ST)) |
| goto complain; |
| } |
| } |
| |
| /* well, not interesting. Just copy and keep going. */ |
| addStmtToIRBB( bb, st ); |
| |
| } /* for (i = 0; i < bb_in->stmts_used; i++) */ |
| |
| return bb; |
| |
| complain: |
| VG_(core_panic)("vg_SP_update_pass: PutI or Dirty which overlaps SP"); |
| |
| } |
| |
| |
| |
| #if 0 |
| for (i = 0; i < bb_in->stmts_used; i++) { |
| st = bb_in->stmts[i]; |
| if (!st) |
| continue; |
| if (st->tag != Ist_Put) |
| goto boring; |
| offP = st->Ist.Put.offset; |
| if (offP != layout->offset_SP) |
| goto boring; |
| szP = sizeofIRType(typeOfIRExpr(bb_in->tyenv, st->Ist.Put.data)); |
| if (szP != layout->sizeof_SP) |
| goto boring; |
| vg_assert(isAtom(st->Ist.Put.data)); |
| |
| /* I don't know if it's really necessary to say that the call reads |
| the stack pointer. But anyway, we do. */ |
| dcall = unsafeIRDirty_0_N( |
| mkIRCallee(1, "VG_(unknown_esp_update)", |
| (HWord)&VG_(unknown_esp_update)), |
| mkIRExprVec_1(st->Ist.Put.data) |
| ); |
| dcall->nFxState = 1; |
| dcall->fxState[0].fx = Ifx_Read; |
| dcall->fxState[0].offset = layout->offset_SP; |
| dcall->fxState[0].size = layout->sizeof_SP; |
| |
| addStmtToIRBB( bb, IRStmt_Dirty(dcall) ); |
| |
| boring: |
| addStmtToIRBB( bb, st ); |
| } |
| #endif |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Main entry point for the JITter. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* Vex dumps the final code in here. Then we can copy it off |
| wherever we like. */ |
| #define N_TMPBUF 10000 |
| static UChar tmpbuf[N_TMPBUF]; |
| |
| /* Function pointers we must supply to LibVEX in order that it |
| can bomb out and emit messages under Valgrind's control. */ |
| __attribute__ ((noreturn)) |
| static |
| void failure_exit ( void ) |
| { |
| LibVEX_ClearTemporary(True); |
| VG_(printf)("VEX did failure_exit. Bye.\n"); |
| vg_assert(0); //VG_(exit)(1); |
| } |
| |
| static |
| void log_bytes ( Char* bytes, Int nbytes ) |
| { |
| Int i; |
| for (i = 0; i < nbytes-3; i += 4) |
| VG_(printf)("%c%c%c%c", bytes[i], bytes[i+1], bytes[i+2], bytes[i+3]); |
| for (; i < nbytes; i++) |
| VG_(printf)("%c", bytes[i]); |
| } |
| |
| /* Translate the basic block beginning at orig_addr, and add it to |
| the translation cache & translation table. Unless 'debugging' is true, |
| in which case the call is being done for debugging purposes, so |
| (a) throw away the translation once it is made, and (b) produce a |
| load of debugging output. |
| |
| 'tid' is the identity of the thread needing this block. |
| */ |
| |
| /* This stops Vex from chasing into function entry points that we wish |
| to redirect. Chasing across them obviously defeats the redirect |
| mechanism, with bad effects for Memcheck, Addrcheck, and possibly |
| others. */ |
| static Bool chase_into_ok ( Addr64 addr64 ) |
| { |
| Addr addr = (Addr)addr64; |
| if (addr != VG_(code_redirect)(addr)) { |
| if (0) VG_(printf)("not chasing into 0x%x\n", addr); |
| return False; |
| } else { |
| return True; /* ok to chase into 'addr' */ |
| } |
| } |
| |
| Bool VG_(translate) ( ThreadId tid, Addr orig_addr, |
| Bool debugging_translation ) |
| { |
| Addr redir, orig_addr0 = orig_addr; |
| Int orig_size, tmpbuf_used; |
| Bool notrace_until_done; |
| UInt notrace_until_limit = 0; |
| //UInt FULLTRACE_LIMIT = 1; //21068; |
| Segment *seg; |
| |
| /* Make sure Vex is initialised right. */ |
| TranslateResult tres; |
| static Bool vex_init_done = False; |
| |
| if (!vex_init_done) { |
| LibVEX_Init ( &failure_exit, &log_bytes, |
| 1, /* debug_paranoia */ |
| False, /* valgrind support */ |
| &VG_(clo_vex_control) ); |
| vex_init_done = True; |
| } |
| |
| /* profiling ... */ |
| VGP_PUSHCC(VgpTranslate); |
| |
| /* Look in the code redirect table to see if we should |
| translate an alternative address for orig_addr. */ |
| redir = VG_(code_redirect)(orig_addr); |
| |
| if (redir != orig_addr && VG_(clo_verbosity) >= 2) { |
| Char name1[64] = ""; |
| Char name2[64] = ""; |
| VG_(get_fnname_w_offset)(orig_addr, name1, 64); |
| VG_(get_fnname_w_offset)(redir, name2, 64); |
| VG_(message)(Vg_UserMsg, |
| "TRANSLATE: %p (%s) redirected to %p (%s)", |
| orig_addr, name1, |
| redir, name2 ); |
| } |
| orig_addr = redir; |
| |
| /* If codegen tracing, don't start tracing until |
| notrace_until_limit blocks have gone by. This avoids printing |
| huge amounts of useless junk when all we want to see is the last |
| few blocks translated prior to a failure. Set |
| notrace_until_limit to be the number of translations to be made |
| before --trace-codegen= style printing takes effect. */ |
| notrace_until_done = VG_(get_bbs_translated)() >= notrace_until_limit; |
| |
| seg = VG_(find_segment)(orig_addr); |
| |
| if (!debugging_translation) |
| VG_TRACK( pre_mem_read, Vg_CoreTranslate, tid, "", orig_addr, 1 ); |
| |
| if (seg == NULL || |
| !VG_(seg_contains)(seg, orig_addr, 1) || |
| (seg->prot & (VKI_PROT_READ|VKI_PROT_EXEC)) == 0) { |
| /* Code address is bad - deliver a signal instead */ |
| vg_assert(!VG_(is_addressable)(orig_addr, 1)); |
| |
| if (seg != NULL && VG_(seg_contains)(seg, orig_addr, 1)) { |
| vg_assert((seg->prot & VKI_PROT_EXEC) == 0); |
| VG_(synth_fault_perms)(tid, orig_addr); |
| } else |
| VG_(synth_fault_mapping)(tid, orig_addr); |
| |
| return False; |
| } else |
| seg->flags |= SF_CODE; /* contains cached code */ |
| |
| /* If doing any code printing, print a basic block start marker */ |
| if (VG_(clo_trace_codegen)) { |
| Char fnname[64] = ""; |
| VG_(get_fnname_w_offset)(orig_addr, fnname, 64); |
| VG_(printf)( |
| "==== BB %d %s(%p) approx BBs exec'd %llu ====\n", |
| VG_(get_bbs_translated)(), fnname, orig_addr, |
| VG_(bbs_done)); |
| } |
| |
| /* True if a debug trans., or if bit N set in VG_(clo_trace_codegen). */ |
| #if 0 |
| # define DECIDE_IF_PRINTING_CODEGEN_FOR_PHASE(n) \ |
| ( debugging_translation \ |
| || (notrace_until_done \ |
| && (VG_(clo_trace_codegen) & (1 << (n-1))) )) |
| #else |
| # define DECIDE_IF_PRINTING_CODEGEN \ |
| ( debugging_translation \ |
| || (VG_(clo_trace_codegen) > 0 \ |
| && VG_(get_bbs_translated)() >= FULLTRACE_LIMIT)) |
| #endif |
| |
| /* Actually do the translation. */ |
| tres = LibVEX_Translate ( |
| InsnSetX86, InsnSetX86, |
| (Char*)orig_addr, (Addr64)orig_addr, |
| chase_into_ok, |
| &orig_size, |
| tmpbuf, N_TMPBUF, &tmpbuf_used, |
| TL_(instrument), |
| VG_(need_to_handle_SP_assignment)() |
| ? vg_SP_update_pass |
| : NULL, |
| True, /* cleanup after instrumentation */ |
| NULL, |
| VG_(clo_trace_codegen) |
| ); |
| |
| vg_assert(tres == TransOK); |
| vg_assert(tmpbuf_used <= N_TMPBUF); |
| vg_assert(tmpbuf_used > 0); |
| |
| #undef DECIDE_IF_PRINTING_CODEGEN_FOR_PHASE |
| |
| /* Copy data at trans_addr into the translation cache. */ |
| /* Since the .orig_size and .trans_size fields are UShort, be paranoid. */ |
| vg_assert(orig_size > 0 && orig_size < 65536); |
| vg_assert(tmpbuf_used > 0 && tmpbuf_used < 65536); |
| |
| // If debugging, don't do anything with the translated block; we |
| // only did this for the debugging output produced along the way. |
| if (!debugging_translation) { |
| // Note that we use orig_addr0, not orig_addr, which might have been |
| // changed by the redirection |
| VG_(add_to_trans_tab)( orig_addr0, orig_size, |
| (Addr)(&tmpbuf[0]), tmpbuf_used ); |
| } |
| |
| VGP_POPCC(VgpTranslate); |
| |
| return True; |
| } |
| |
| /*--------------------------------------------------------------------*/ |
| /*--- end vg_translate.c ---*/ |
| /*--------------------------------------------------------------------*/ |
| |