bytecode peephole optimization non-looping-loops #186
Description
In the original obfuscation the long j is not set to 0, but I can easily edit the bytecode so that its a 0.
long j = 0L;
long j0 = 3154942220328664823L;
while((j ^ j0) != -4097245258586862040L) {
{
j = -8987102950668834246L;
j0 = 4928288597787943954L;
}
}I think it should be possible to optimize these never-looping-loops relatively easy, but I'm struggling with such generic bytecode analysis.
bytecode of sample above:
L10: lconst_0
L11: ldc2_w 3154942220328664823L
L14: goto L23
.stack full
[redacted]
.end stack
L17: ldc2_w -8987102950668834246L
L20: ldc2_w 4928288597787943954L
.stack full
[redacted]
.end stack
L23: lxor
L24: ldc2_w -4097245258586862040L
L27: lcmp
L28: ifne L17 other sample of similar never looping thing:
long j = 0L;
long j0 = 6913978580415874324L;
while(true) {
int i = (j < j0) ? -1 : (j == j0) ? 0 : 1;
if (i == 0) {
break;
}
if (i != -1) {
j = 1371682301368612379L;
j0 = 98363365008051593L;
} else {
// real code
break;
}
}Edit: maybe that whole thing is also in another non-looping-loop:
label0: while(true) {
long j1 = 0L;
long j2 = 5954778881033184416L;
while(true) {
int i0 = (j1 < j2) ? -1 : (j1 == j2) ? 0 : 1;
if (i0 == 0) {
break;
}
if (i0 == -1) {
break label0;
}
j1 = 234223452657458715L;
j2 = 6736292361240488430L;
}
}