diff options
Diffstat (limited to 'src/VBox/Runtime/common/compiler/vcc/stack-probe-vcc.asm')
| -rw-r--r-- | src/VBox/Runtime/common/compiler/vcc/stack-probe-vcc.asm | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/compiler/vcc/stack-probe-vcc.asm b/src/VBox/Runtime/common/compiler/vcc/stack-probe-vcc.asm new file mode 100644 index 00000000..da2e2965 --- /dev/null +++ b/src/VBox/Runtime/common/compiler/vcc/stack-probe-vcc.asm @@ -0,0 +1,157 @@ +; $Id: stack-probe-vcc.asm $ +;; @file +; IPRT - Stack related Visual C++ support routines. +; + +; +; Copyright (C) 2022-2023 Oracle and/or its affiliates. +; +; This file is part of VirtualBox base platform packages, as +; available from https://www.virtualbox.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, in version 3 of the +; License. +; +; 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 <https://www.gnu.org/licenses>. +; +; The contents of this file may alternatively be used under the terms +; of the Common Development and Distribution License Version 1.0 +; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included +; in the VirtualBox distribution, in which case the provisions of the +; CDDL are applicable instead of those of the GPL. +; +; You may elect to license modified versions of this file under the +; terms and conditions of either the GPL or the CDDL or both. +; +; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0 +; + + + +;********************************************************************************************************************************* +;* Header Files * +;********************************************************************************************************************************* +%if 0 ; YASM's builtin SEH64 support doesn't cope well with code alignment, so use our own. + %define RT_ASM_WITH_SEH64 +%else + %define RT_ASM_WITH_SEH64_ALT +%endif +%include "iprt/asmdefs.mac" +%include "iprt/x86.mac" + + +;; +; Probe stack to trigger guard faults, and for x86 to allocate stack space. +; +; @param xAX Frame size. +; @uses AMD64: Probably nothing. EAX is certainly not supposed to change. +; x86: ESP = ESP - EAX; EFLAGS, nothing else +; +ALIGNCODE(64) +GLOBALNAME_RAW __alloca_probe, __alloca_probe, function +BEGINPROC_RAW __chkstk + push xBP + SEH64_PUSH_xBP + mov xBP, xSP + SEH64_SET_FRAME_xBP 0 + push xAX + SEH64_PUSH_GREG xAX + push xBX + SEH64_PUSH_GREG xBX + SEH64_END_PROLOGUE + + ; + ; Adjust eax so we're relative to [xBP - xCB*2]. + ; + sub xAX, xCB * 4 + jle .touch_loop_done ; jump if rax < xCB*4, very unlikely + + ; + ; Subtract what's left of the current page from eax and only engage + ; the touch loop if (int)xAX > 0. + ; + lea ebx, [ebp - xCB * 2] + and ebx, PAGE_SIZE - 1 + sub xAX, xBX + jnl .touch_loop ; jump if pages to touch. + +.touch_loop_done: + pop xBX + pop xAX + leave +%ifndef RT_ARCH_X86 + ret +%else + ; + ; Do the stack space allocation and jump to the return location. + ; + sub esp, eax + add esp, 4 + jmp dword [esp + eax - 4] +%endif + + ; + ; The touch loop. + ; +.touch_loop: + sub xBX, PAGE_SIZE +%if 1 + mov [xBP + xBX - xCB * 2], bl +%else + or byte [xBP + xBX - xCB * 2], 0 ; non-destructive variant... +%endif + sub xAX, PAGE_SIZE + jnl .touch_loop + jmp .touch_loop_done +ENDPROC_RAW __chkstk + + +%ifdef RT_ARCH_X86 +;; +; 8 and 16 byte aligned alloca w/ probing. +; +; This routine adjusts the allocation size so __chkstk will return a +; correctly aligned allocation. +; +; @param xAX Unaligned allocation size. +; +%macro __alloc_probe_xxx 1 +ALIGNCODE(16) +BEGINPROC_RAW __alloca_probe_ %+ %1 + push ecx + + ; + ; Calc the ESP address after the allocation and adjust EAX so that it + ; will be aligned as desired. + ; + lea ecx, [esp + 8] + sub ecx, eax + and ecx, %1 - 1 + add eax, ecx + jc .bad_alloc_size +.continue: + + pop ecx + jmp __alloca_probe + +.bad_alloc_size: + %ifdef RT_STRICT + int3 + %endif + or eax, 0xfffffff0 + jmp .continue +ENDPROC_RAW __alloca_probe_ %+ %1 +%endmacro + +__alloc_probe_xxx 16 +__alloc_probe_xxx 8 +%endif ; RT_ARCH_X86 + |