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+/*
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+ * Copyright (C) 2009 H. Peter Anvin <hpa@zytor.com>
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+ *
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+ * This program is free software; you can redistribute it and/or
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+ * modify it under the terms of the GNU General Public License
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+ * as published by the Free Software Foundation; either version 2
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+ * of the License, or (at your option) any later version.
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+ *
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+ * This program is distributed in the hope that it will be useful,
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+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
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+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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+ * GNU General Public License for more details.
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+ *
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+ * You should have received a copy of the GNU General Public License
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+ * along with this program; if not, write to the Free Software
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+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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+ */
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+
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+FILE_LICENCE ( GPL2_OR_LATER )
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+
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+ .text
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+ .arch i386
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+ .code16
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+
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+/****************************************************************************
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+ * Set/clear CF on the stack as appropriate, assumes stack is as it should
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+ * be immediately before IRET
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+ ****************************************************************************
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+ */
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+ .section ".text16", "ax", @progbits
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+ .globl patch_cf
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+patch_cf:
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+ pushw %bp
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+ movw %sp, %bp
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+ setc 8(%bp) /* Set/reset CF; clears PF, AF, ZF, SF */
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+ popw %bp
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+ ret
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+ .size patch_cf, . - patch_cf
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