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# Copyright (c) 2007-2008 The Hewlett-Packard Development Company
# All rights reserved.
#
# The license below extends only to copyright in the software and shall
# not be construed as granting a license to any other intellectual
# property including but not limited to intellectual property relating
# to a hardware implementation of the functionality of the software
# licensed hereunder. You may use the software subject to the license
# terms below provided that you ensure that this notice is replicated
# unmodified and in its entirety in all distributions of the software,
# modified or unmodified, in source code or in binary form.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met: redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer;
# redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution;
# neither the name of the copyright holders nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# Authors: Gabe Black
microcode = '''
def macroop RET_NEAR
{
# Make the default data size of rets 64 bits in 64 bit mode
.adjust_env oszIn64Override
.function_return
ld t1, ss, [1, t0, rsp]
# Check address of return
addi rsp, rsp, dsz
wripi t1, 0
};
def macroop RET_NEAR_I
{
# Make the default data size of rets 64 bits in 64 bit mode
.adjust_env oszIn64Override
.function_return
limm t2, imm
ld t1, ss, [1, t0, rsp]
# Check address of return
addi rsp, rsp, dsz
add rsp, rsp, t2
wripi t1, 0
};
def macroop RET_FAR {
.adjust_env oszIn64Override
.function_return
# Get the return RIP
ld t1, ss, [1, t0, rsp]
# Get the return CS
ld t2, ss, [1, t0, rsp], ssz
# increment the stack pointer to pop the instruction pointer
# and the code segment from the stack.
addi rsp, rsp, dsz
addi rsp, rsp, dsz
# Get the rpl
andi t3, t2, 0x3
# Get the cpl
# Here we'd check if we're changing priviledge levels. We'll just hope
# that doesn't happen yet.
# Do stuff if they're equal
andi t0, t2, 0xFC, flags=(EZF,), dataSize=2
br label("processDescriptor"), flags=(CEZF,)
andi t3, t2, 0xF8, dataSize=8
andi t0, t2, 0x4, flags=(EZF,), dataSize=2
br label("globalDescriptor"), flags=(CEZF,)
ld t3, tsl, [1, t0, t3], dataSize=8
br label("processDescriptor")
globalDescriptor:
ld t3, tsg, [1, t0, t3], dataSize=8
processDescriptor:
chks t2, t3, IretCheck, dataSize=8
# There should be validity checks on the RIP checks here, but I'll do
# that later.
wrdl cs, t3, t2
wrsel cs, t2
wrip t0, t1
# br label("end")
# Do other stuff if they're not.
#end:
# fault "NoFault"
};
'''
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