blob: a9e4c5b5cb0fbef445d683b0b3a4e2310e01bde3 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
//===- InductionVars.cpp - Induction Variable Cannonicalization code --------=//
//
// This file implements induction variable cannonicalization of loops.
//
// Specifically, after this executes, the following is true:
// - There is a single induction variable for each loop (that used to contain
// at least one induction variable)
// - This induction variable starts at 0 and steps by 1 per iteration
// - All other preexisting induction variables are adjusted to operate in
// terms of this primary induction variable
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/Intervals.h"
#include "llvm/Opt/AllOpts.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/Tools/STLExtras.h"
static bool ProcessInterval(cfg::Interval *Int) {
if (!Int->isLoop()) return false; // Not a loop? Ignore it!
cerr << "Found Looping Interval: " << Int; //->HeaderNode;
return false;
}
static bool ProcessIntervalPartition(cfg::IntervalPartition &IP) {
// This currently just prints out information about the interval structure
// of the method...
static unsigned N = 0;
cerr << "\n***********Interval Partition #" << (++N) << "************\n\n";
copy(IP.begin(), IP.end(), ostream_iterator<cfg::Interval*>(cerr, "\n"));
cerr << "\n*********** PERFORMING WORK ************\n\n";
// Loop over all of the intervals in the partition and look for induction
// variables in intervals that represent loops.
//
return reduce_apply(IP.begin(), IP.end(), bitwise_or<bool>(), false,
ptr_fun(ProcessInterval));
}
// DoInductionVariableCannonicalize - Simplify induction variables in loops
//
bool DoInductionVariableCannonicalize(Method *M) {
cfg::IntervalPartition *IP = new cfg::IntervalPartition(M);
bool Changed = false;
while (!IP->isDegeneratePartition()) {
Changed |= ProcessIntervalPartition(*IP);
// Calculate the reduced version of this graph until we get to an
// irreducible graph or a degenerate graph...
//
cfg::IntervalPartition *NewIP = new cfg::IntervalPartition(*IP, false);
if (NewIP->size() == IP->size()) {
cerr << "IRREDUCIBLE GRAPH FOUND!!!\n";
return Changed;
}
delete IP;
IP = NewIP;
}
delete IP;
return Changed;
}
|
