1# Copyright (c) 2007-2008 The Hewlett-Packard Development Company
2# All rights reserved.
3#
4# The license below extends only to copyright in the software and shall
5# not be construed as granting a license to any other intellectual
6# property including but not limited to intellectual property relating
7# to a hardware implementation of the functionality of the software
8# licensed hereunder.  You may use the software subject to the license
9# terms below provided that you ensure that this notice is replicated
10# unmodified and in its entirety in all distributions of the software,
11# modified or unmodified, in source code or in binary form.
12#
13# Redistribution and use in source and binary forms, with or without
14# modification, are permitted provided that the following conditions are
15# met: redistributions of source code must retain the above copyright
16# notice, this list of conditions and the following disclaimer;
17# redistributions in binary form must reproduce the above copyright
18# notice, this list of conditions and the following disclaimer in the
19# documentation and/or other materials provided with the distribution;
20# neither the name of the copyright holders nor the names of its
21# contributors may be used to endorse or promote products derived from
22# this software without specific prior written permission.
23#
24# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
25# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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27# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
28# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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30# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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34# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35#
36# Authors: Gabe Black
37
38microcode = '''
39def macroop SCAS_M {
40    # Find the constant we need to either add or subtract from rdi
41    ruflag t0, 10
42    movi t2, t2, dsz, flags=(CEZF,), dataSize=asz
43    subi t3, t0, dsz, dataSize=asz
44    mov t2, t2, t3, flags=(nCEZF,), dataSize=asz
45
46    ld t1, es, [1, t0, rdi]
47    sub t0, rax, t1, flags=(OF, SF, ZF, AF, PF, CF)
48
49    add rdi, rdi, t2, dataSize=asz
50};
51
52#
53# Versions which have the rep prefix. These could benefit from some loop
54# unrolling.
55#
56
57def macroop SCAS_E_M {
58    and t0, rcx, rcx, flags=(EZF,), dataSize=asz
59    br label("end"), flags=(CEZF,)
60
61    # Find the constant we need to either add or subtract from rdi
62    ruflag t0, 10
63    movi t2, t2, dsz, flags=(CEZF,), dataSize=asz
64    subi t3, t0, dsz, dataSize=asz
65    mov t2, t2, t3, flags=(nCEZF,), dataSize=asz
66
67topOfLoop:
68    ld t1, es, [1, t0, rdi]
69    sub t0, rax, t1, flags=(OF, SF, ZF, AF, PF, CF)
70
71    subi rcx, rcx, 1, flags=(EZF,), dataSize=asz
72    add rdi, rdi, t2, dataSize=asz
73    br label("topOfLoop"), flags=(CSTRZnEZF,)
74end:
75    fault "NoFault"
76};
77
78def macroop SCAS_N_M {
79    and t0, rcx, rcx, flags=(EZF,), dataSize=asz
80    br label("end"), flags=(CEZF,)
81
82    # Find the constant we need to either add or subtract from rdi
83    ruflag t0, 10
84    movi t2, t2, dsz, flags=(CEZF,), dataSize=asz
85    subi t3, t0, dsz, dataSize=asz
86    mov t2, t2, t3, flags=(nCEZF,), dataSize=asz
87
88topOfLoop:
89    ld t1, es, [1, t0, rdi]
90    sub t0, rax, t1, flags=(OF, SF, ZF, AF, PF, CF)
91
92    subi rcx, rcx, 1, flags=(EZF,), dataSize=asz
93    add rdi, rdi, t2, dataSize=asz
94    br label("topOfLoop"), flags=(CSTRnZnEZF,)
95end:
96    fault "NoFault"
97};
98
99'''
100