1 | /*****************************************************************************/ |
2 | /* */ |
3 | /* coptptrstore.h */ |
4 | /* */ |
5 | /* Optimize stores through pointers */ |
6 | /* */ |
7 | /* */ |
8 | /* */ |
9 | /* (C) 2012, Ullrich von Bassewitz */ |
10 | /* Roemerstrasse 52 */ |
11 | /* D-70794 Filderstadt */ |
12 | /* EMail: uz@cc65.org */ |
13 | /* */ |
14 | /* */ |
15 | /* This software is provided 'as-is', without any expressed or implied */ |
16 | /* warranty. In no event will the authors be held liable for any damages */ |
17 | /* arising from the use of this software. */ |
18 | /* */ |
19 | /* Permission is granted to anyone to use this software for any purpose, */ |
20 | /* including commercial applications, and to alter it and redistribute it */ |
21 | /* freely, subject to the following restrictions: */ |
22 | /* */ |
23 | /* 1. The origin of this software must not be misrepresented; you must not */ |
24 | /* claim that you wrote the original software. If you use this software */ |
25 | /* in a product, an acknowledgment in the product documentation would be */ |
26 | /* appreciated but is not required. */ |
27 | /* 2. Altered source versions must be plainly marked as such, and must not */ |
28 | /* be misrepresented as being the original software. */ |
29 | /* 3. This notice may not be removed or altered from any source */ |
30 | /* distribution. */ |
31 | /* */ |
32 | /*****************************************************************************/ |
33 | |
34 | |
35 | |
36 | #ifndef COPTPTRSTORE_H |
37 | #define COPTPTRSTORE_H |
38 | |
39 | |
40 | |
41 | /* cc65 */ |
42 | #include "codeseg.h" |
43 | |
44 | |
45 | |
46 | /*****************************************************************************/ |
47 | /* Code */ |
48 | /*****************************************************************************/ |
49 | |
50 | |
51 | |
52 | unsigned OptPtrStore1 (CodeSeg* S); |
53 | /* Search for the sequence: |
54 | ** |
55 | ** clc |
56 | ** adc xxx |
57 | ** bcc L |
58 | ** inx |
59 | ** L: jsr pushax |
60 | ** ldx #$00 |
61 | ** lda yyy |
62 | ** ldy #$00 |
63 | ** jsr staspidx |
64 | ** |
65 | ** and replace it by: |
66 | ** |
67 | ** sta ptr1 |
68 | ** stx ptr1+1 |
69 | ** ldy xxx |
70 | ** ldx #$00 |
71 | ** lda yyy |
72 | ** sta (ptr1),y |
73 | ** |
74 | ** or by |
75 | ** |
76 | ** ldy xxx |
77 | ** ldx #$00 |
78 | ** lda yyy |
79 | ** sta (zp),y |
80 | ** |
81 | ** or by |
82 | ** |
83 | ** ldy xxx |
84 | ** ldx #$00 |
85 | ** lda yyy |
86 | ** sta label,y |
87 | ** |
88 | ** or by |
89 | ** |
90 | ** ldy xxx |
91 | ** ldx #$00 |
92 | ** lda yyy |
93 | ** sta $xxxx,y |
94 | ** |
95 | ** depending on the two instructions preceeding the sequence above. |
96 | */ |
97 | |
98 | unsigned OptPtrStore2 (CodeSeg* S); |
99 | /* Search for the sequence: |
100 | ** |
101 | ** clc |
102 | ** adc xxx |
103 | ** bcc L |
104 | ** inx |
105 | ** L: jsr pushax |
106 | ** ldy yyy |
107 | ** ldx #$00 |
108 | ** lda (sp),y |
109 | ** ldy #$00 |
110 | ** jsr staspidx |
111 | ** |
112 | ** and replace it by: |
113 | ** |
114 | ** sta ptr1 |
115 | ** stx ptr1+1 |
116 | ** ldy yyy-2 |
117 | ** ldx #$00 |
118 | ** lda (sp),y |
119 | ** ldy xxx |
120 | ** sta (ptr1),y |
121 | ** |
122 | ** or by |
123 | ** |
124 | ** ldy yyy-2 |
125 | ** ldx #$00 |
126 | ** lda (sp),y |
127 | ** ldy xxx |
128 | ** sta (zp),y |
129 | ** |
130 | ** or by |
131 | ** |
132 | ** ldy yyy-2 |
133 | ** ldx #$00 |
134 | ** lda (sp),y |
135 | ** ldy xxx |
136 | ** sta label,y |
137 | ** |
138 | ** or by |
139 | ** |
140 | ** ldy yyy-2 |
141 | ** ldx #$00 |
142 | ** lda (sp),y |
143 | ** ldy xxx |
144 | ** sta $xxxx,y |
145 | ** |
146 | ** depending on the code preceeding the sequence above. |
147 | */ |
148 | |
149 | unsigned OptPtrStore3 (CodeSeg* S); |
150 | /* Search for the sequence: |
151 | ** |
152 | ** jsr pushax |
153 | ** ldy xxx |
154 | ** jsr ldauidx |
155 | ** subop |
156 | ** ldy yyy |
157 | ** jsr staspidx |
158 | ** |
159 | ** and replace it by: |
160 | ** |
161 | ** sta ptr1 |
162 | ** stx ptr1+1 |
163 | ** ldy xxx |
164 | ** ldx #$00 |
165 | ** lda (ptr1),y |
166 | ** subop |
167 | ** ldy yyy |
168 | ** sta (ptr1),y |
169 | ** |
170 | ** In case a/x is loaded from the register bank before the pushax, we can even |
171 | ** use the register bank instead of ptr1. |
172 | */ |
173 | |
174 | |
175 | |
176 | /* End of coptptrstore.h */ |
177 | |
178 | #endif |
179 | |