1/*****************************************************************************/
2/* */
3/* coptadd.h */
4/* */
5/* Optimize addition sequences */
6/* */
7/* */
8/* */
9/* (C) 2001-2005, 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 COPTADD_H
37#define COPTADD_H
38
39
40
41/* cc65 */
42#include "codeseg.h"
43
44
45
46/*****************************************************************************/
47/* Optimize additions */
48/*****************************************************************************/
49
50
51
52unsigned OptAdd1 (CodeSeg* S);
53/* Search for the sequence
54**
55** jsr pushax
56** ldy xxx
57** ldx #$00
58** lda (sp),y
59** jsr tosaddax
60**
61** and replace it by:
62**
63** ldy xxx-2
64** clc
65** adc (sp),y
66** bcc L
67** inx
68** L:
69*/
70
71unsigned OptAdd2 (CodeSeg* S);
72/* Search for the sequence
73**
74** ldy #xx
75** lda (sp),y
76** tax
77** dey
78** lda (sp),y
79** ldy #$yy
80** jsr addeqysp
81**
82** and replace it by:
83**
84** ldy #xx-1
85** lda (sp),y
86** ldy #yy
87** clc
88** adc (sp),y
89** sta (sp),y
90** ldy #xx
91** lda (sp),y
92** ldy #yy+1
93** adc (sp),y
94** sta (sp),y
95**
96** provided that a/x is not used later.
97*/
98
99unsigned OptAdd3 (CodeSeg* S);
100/* Search for the sequence
101**
102** jsr pushax
103** ldx #$00
104** lda xxx
105** jsr tosaddax
106**
107** and replace it by
108**
109** clc
110** adc xxx
111** bcc L1
112** inx
113** L1:
114*/
115
116unsigned OptAdd4 (CodeSeg* S);
117/* Search for the sequence
118**
119** jsr pushax
120** lda xxx
121** ldx yyy
122** jsr tosaddax
123**
124** and replace it by
125**
126** clc
127** adc xxx
128** pha
129** txa
130** adc yyy
131** tax
132** pla
133*/
134
135unsigned OptAdd5 (CodeSeg* S);
136/* Search for a call to incaxn and replace it by an 8 bit add if the X register
137** is not used later.
138*/
139
140unsigned OptAdd6 (CodeSeg* S);
141/* Search for the sequence
142**
143** adc ...
144** bcc L
145** inx
146** L:
147**
148** and remove the handling of the high byte if X is not used later.
149*/
150
151
152
153/* End of coptadd.h */
154
155#endif
156