| |
| /*--------------------------------------------------------------------*/ |
| /*--- The core dispatch loop, for jumping to a code address. ---*/ |
| /*--- dispatch-x86-linux.S ---*/ |
| /*--------------------------------------------------------------------*/ |
| |
| /* |
| This file is part of Valgrind, a dynamic binary instrumentation |
| framework. |
| |
| Copyright (C) 2000-2008 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 "pub_core_basics_asm.h" |
| #include "pub_core_dispatch_asm.h" |
| #include "pub_core_transtab_asm.h" |
| #include "libvex_guest_offsets.h" /* for OFFSET_x86_EIP */ |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- ---*/ |
| /*--- The dispatch loop. VG_(run_innerloop) is used to ---*/ |
| /*--- run all translations except no-redir ones. ---*/ |
| /*--- ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /*----------------------------------------------------*/ |
| /*--- Preamble (set everything up) ---*/ |
| /*----------------------------------------------------*/ |
| |
| /* signature: |
| UWord VG_(run_innerloop) ( void* guest_state, UWord do_profiling ); |
| */ |
| .text |
| .globl VG_(run_innerloop) |
| .type VG_(run_innerloop), @function |
| VG_(run_innerloop): |
| /* 4(%esp) holds guest_state */ |
| /* 8(%esp) holds do_profiling */ |
| |
| /* ----- entry point to VG_(run_innerloop) ----- */ |
| pushl %ebx |
| pushl %ecx |
| pushl %edx |
| pushl %esi |
| pushl %edi |
| pushl %ebp |
| |
| /* 28(%esp) holds guest_state */ |
| /* 32(%esp) holds do_profiling */ |
| |
| /* Set up the guest state pointer */ |
| movl 28(%esp), %ebp |
| |
| /* fetch %EIP into %eax */ |
| movl OFFSET_x86_EIP(%ebp), %eax |
| |
| /* set host FPU control word to the default mode expected |
| by VEX-generated code. See comments in libvex.h for |
| more info. */ |
| finit |
| pushl $0x027F |
| fldcw (%esp) |
| addl $4, %esp |
| |
| /* set host SSE control word to the default mode expected |
| by VEX-generated code. */ |
| cmpl $0, VG_(machine_x86_have_mxcsr) |
| jz L1 |
| pushl $0x1F80 |
| ldmxcsr (%esp) |
| addl $4, %esp |
| L1: |
| /* set dir flag to known value */ |
| cld |
| |
| /* fall into main loop (the right one) */ |
| cmpl $0, 32(%esp) /* do_profiling */ |
| je VG_(run_innerloop__dispatch_unprofiled) |
| jmp VG_(run_innerloop__dispatch_profiled) |
| /*NOTREACHED*/ |
| |
| /*----------------------------------------------------*/ |
| /*--- NO-PROFILING (standard) dispatcher ---*/ |
| /*----------------------------------------------------*/ |
| |
| .align 16 |
| .global VG_(run_innerloop__dispatch_unprofiled) |
| VG_(run_innerloop__dispatch_unprofiled): |
| /* AT ENTRY: %eax is next guest addr, %ebp is possibly |
| modified guest state ptr */ |
| |
| /* Has the guest state pointer been messed with? If yes, exit. */ |
| cmpl 28(%esp), %ebp |
| jnz gsp_changed |
| |
| /* save the jump address in the guest state */ |
| movl %eax, OFFSET_x86_EIP(%ebp) |
| |
| /* Are we out of timeslice? If yes, defer to scheduler. */ |
| subl $1, VG_(dispatch_ctr) |
| jz counter_is_zero |
| |
| /* try a fast lookup in the translation cache */ |
| movl %eax, %ebx /* next guest addr */ |
| andl $ VG_TT_FAST_MASK, %ebx /* entry# */ |
| movl 0+VG_(tt_fast)(,%ebx,8), %esi /* .guest */ |
| movl 4+VG_(tt_fast)(,%ebx,8), %edi /* .host */ |
| cmpl %eax, %esi |
| jnz fast_lookup_failed |
| |
| /* Found a match. Jump to .host. */ |
| jmp *%edi |
| ud2 /* persuade insn decoders not to speculate past here */ |
| /* generated code should run, then jump back to |
| VG_(run_innerloop__dispatch_unprofiled). */ |
| /*NOTREACHED*/ |
| |
| /*----------------------------------------------------*/ |
| /*--- PROFILING dispatcher (can be much slower) ---*/ |
| /*----------------------------------------------------*/ |
| |
| .align 16 |
| .global VG_(run_innerloop__dispatch_profiled) |
| VG_(run_innerloop__dispatch_profiled): |
| /* AT ENTRY: %eax is next guest addr, %ebp is possibly |
| modified guest state ptr */ |
| |
| /* Has the guest state pointer been messed with? If yes, exit. */ |
| cmpl 28(%esp), %ebp |
| jnz gsp_changed |
| |
| /* save the jump address in the guest state */ |
| movl %eax, OFFSET_x86_EIP(%ebp) |
| |
| /* Are we out of timeslice? If yes, defer to scheduler. */ |
| subl $1, VG_(dispatch_ctr) |
| jz counter_is_zero |
| |
| /* try a fast lookup in the translation cache */ |
| movl %eax, %ebx /* next guest addr */ |
| andl $ VG_TT_FAST_MASK, %ebx /* entry# */ |
| movl 0+VG_(tt_fast)(,%ebx,8), %esi /* .guest */ |
| movl 4+VG_(tt_fast)(,%ebx,8), %edi /* .host */ |
| cmpl %eax, %esi |
| jnz fast_lookup_failed |
| |
| /* increment bb profile counter */ |
| /* note: innocuous as this sounds, it causes a huge amount more |
| stress on D1 and significantly slows everything down. */ |
| movl VG_(tt_fastN)(,%ebx,4), %edx |
| /* Use "addl $1", not "incl", to avoid partial-flags stall on P4 */ |
| addl $1, (%edx) |
| |
| /* Found a match. Jump to .host. */ |
| jmp *%edi |
| ud2 /* persuade insn decoders not to speculate past here */ |
| /* generated code should run, then jump back to |
| VG_(run_innerloop__dispatch_profiled). */ |
| /*NOTREACHED*/ |
| |
| /*----------------------------------------------------*/ |
| /*--- exit points ---*/ |
| /*----------------------------------------------------*/ |
| |
| gsp_changed: |
| /* Someone messed with the gsp. Have to |
| defer to scheduler to resolve this. dispatch ctr |
| is not yet decremented, so no need to increment. */ |
| /* %EIP is NOT up to date here. First, need to write |
| %eax back to %EIP, but without trashing %ebp since |
| that holds the value we want to return to the scheduler. |
| Hence use %esi transiently for the guest state pointer. */ |
| movl 28(%esp), %esi |
| movl %eax, OFFSET_x86_EIP(%esi) |
| movl %ebp, %eax |
| jmp run_innerloop_exit |
| /*NOTREACHED*/ |
| |
| counter_is_zero: |
| /* %EIP is up to date here */ |
| /* back out decrement of the dispatch counter */ |
| addl $1, VG_(dispatch_ctr) |
| movl $ VG_TRC_INNER_COUNTERZERO, %eax |
| jmp run_innerloop_exit |
| /*NOTREACHED*/ |
| |
| fast_lookup_failed: |
| /* %EIP is up to date here */ |
| /* back out decrement of the dispatch counter */ |
| addl $1, VG_(dispatch_ctr) |
| movl $ VG_TRC_INNER_FASTMISS, %eax |
| jmp run_innerloop_exit |
| /*NOTREACHED*/ |
| |
| |
| |
| /* All exits from the dispatcher go through here. %eax holds |
| the return value. |
| */ |
| run_innerloop_exit: |
| /* We're leaving. Check that nobody messed with |
| %mxcsr or %fpucw. We can't mess with %eax here as it |
| holds the tentative return value, but any other is OK. */ |
| #if !defined(ENABLE_INNER) |
| /* This check fails for self-hosting, so skip in that case */ |
| pushl $0 |
| fstcw (%esp) |
| cmpl $0x027F, (%esp) |
| popl %esi /* get rid of the word without trashing %eflags */ |
| jnz invariant_violation |
| #endif |
| cmpl $0, VG_(machine_x86_have_mxcsr) |
| jz L2 |
| pushl $0 |
| stmxcsr (%esp) |
| andl $0xFFFFFFC0, (%esp) /* mask out status flags */ |
| cmpl $0x1F80, (%esp) |
| popl %esi |
| jnz invariant_violation |
| L2: /* otherwise we're OK */ |
| jmp run_innerloop_exit_REALLY |
| |
| invariant_violation: |
| movl $ VG_TRC_INVARIANT_FAILED, %eax |
| jmp run_innerloop_exit_REALLY |
| |
| run_innerloop_exit_REALLY: |
| popl %ebp |
| popl %edi |
| popl %esi |
| popl %edx |
| popl %ecx |
| popl %ebx |
| ret |
| .size VG_(run_innerloop), .-VG_(run_innerloop) |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- ---*/ |
| /*--- A special dispatcher, for running no-redir ---*/ |
| /*--- translations. Just runs the given translation once. ---*/ |
| /*--- ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* signature: |
| void VG_(run_a_noredir_translation) ( UWord* argblock ); |
| */ |
| |
| /* Run a no-redir translation. argblock points to 4 UWords, 2 to carry args |
| and 2 to carry results: |
| 0: input: ptr to translation |
| 1: input: ptr to guest state |
| 2: output: next guest PC |
| 3: output: guest state pointer afterwards (== thread return code) |
| */ |
| .align 16 |
| .global VG_(run_a_noredir_translation) |
| .type VG_(run_a_noredir_translation), @function |
| VG_(run_a_noredir_translation): |
| /* Save callee-saves regs */ |
| pushl %esi |
| pushl %edi |
| pushl %ebp |
| pushl %ebx |
| |
| movl 20(%esp), %edi /* %edi = argblock */ |
| movl 4(%edi), %ebp /* argblock[1] */ |
| jmp *0(%edi) /* argblock[0] */ |
| /*NOTREACHED*/ |
| ud2 |
| /* If the translation has been correctly constructed, we |
| should resume at the the following label. */ |
| .global VG_(run_a_noredir_translation__return_point) |
| VG_(run_a_noredir_translation__return_point): |
| movl 20(%esp), %edi |
| movl %eax, 8(%edi) /* argblock[2] */ |
| movl %ebp, 12(%edi) /* argblock[3] */ |
| |
| popl %ebx |
| popl %ebp |
| popl %edi |
| popl %esi |
| ret |
| .size VG_(run_a_noredir_translation), .-VG_(run_a_noredir_translation) |
| |
| |
| /* Let the linker know we don't need an executable stack */ |
| .section .note.GNU-stack,"",@progbits |
| |
| /*--------------------------------------------------------------------*/ |
| /*--- end ---*/ |
| /*--------------------------------------------------------------------*/ |