Commit | Line | Data |
---|---|---|
42d6e430 BJ |
1 | #include <stdio.h> |
2 | #include "def.h" | |
3 | #include "3.def.h" | |
4 | ||
5 | #define BRANCHTYPE(t) (t == STOPVX || t == RETVX || t == BRKVX || t == NXTVX || t == GOVX) | |
6 | #define MAXCHUNK 20 | |
7 | /* if else clause smaller than MAXCHUNK and smaller than then clause, | |
8 | and there is no reason not to negate the if, negate the if */ | |
9 | ||
10 | getthen(v) /* turn IFVX into THEN when appropriate, create else ifs where possible */ | |
11 | VERT v; | |
12 | { | |
13 | VERT tch, fch; | |
14 | int tn,fn; | |
15 | int recvar; | |
16 | ||
17 | if (NTYPE(v) == IFVX) | |
18 | { | |
19 | tch = LCHILD(v,THEN); | |
20 | fch = LCHILD(v,ELSE); | |
21 | if (!DEFINED(fch)) | |
22 | mkthen(v); | |
23 | else if (!DEFINED(tch)) | |
24 | { | |
25 | negate(v); | |
26 | mkthen(v); | |
27 | } | |
28 | else if (BRANCHTYPE(NTYPE(tch))) | |
29 | mkthen(v); | |
30 | else if (BRANCHTYPE(NTYPE(fch))) | |
31 | { | |
32 | negate(v); | |
33 | mkthen(v); | |
34 | } | |
35 | else if (NTYPE(fch) != IFVX || DEFINED(RSIB(fch))) /* not an else if */ | |
36 | if ( NTYPE(tch) == IFVX && !DEFINED(RSIB(tch))) | |
37 | /* invert into else if */ | |
38 | negate(v); | |
39 | else | |
40 | { | |
41 | /* asoc(v,n) returns number of statements associated with v | |
42 | if <= n, -1 otherwise */ | |
43 | tn = asoc(tch,MAXCHUNK); | |
44 | fn = asoc(fch,MAXCHUNK); | |
45 | if (fn >= 0 && (tn < 0 || fn < tn)) | |
46 | /* else clause smaller */ | |
47 | negate(v); | |
48 | } | |
49 | } | |
50 | RECURSE(getthen,v,recvar); | |
51 | } | |
52 | ||
53 | mkthen(v) | |
54 | VERT v; | |
55 | { | |
56 | VERT w,tc; | |
57 | w = LCHILD(v,ELSE); | |
58 | tc = LCHILD(v,THEN); | |
59 | ASSERT(!DEFINED(w) || (DEFINED(tc) && BRANCHTYPE(NTYPE(tc)) ),mkthen); | |
60 | if (DEFINED(w)) | |
61 | { | |
62 | insib(v,w); | |
63 | LCHILD(v,ELSE) = UNDEFINED; | |
64 | } | |
65 | ASSERT(IFTHEN(v),mkthen); | |
66 | } | |
67 | ||
68 | ||
69 | negate(v) | |
70 | VERT v; | |
71 | { | |
72 | ASSERT(NTYPE(v) == IFVX,negate); | |
73 | exchange(&LCHILD(v,THEN), &LCHILD(v,ELSE)); | |
74 | NEG(v) = !NEG(v); | |
75 | } |