Remove -enable-lsr-nested in time for 3.1.
Tests cases have been removed but attached to open PR12330.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153286 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index 82d918e..e0005ba 100644
--- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -77,9 +77,6 @@
#include <algorithm>
using namespace llvm;
-static cl::opt<bool> EnableNested(
- "enable-lsr-nested", cl::Hidden, cl::desc("Enable LSR on nested loops"));
-
static cl::opt<bool> EnableRetry(
"enable-lsr-retry", cl::Hidden, cl::desc("Enable LSR retry"));
@@ -824,36 +821,20 @@
const Loop *L,
ScalarEvolution &SE, DominatorTree &DT) {
if (const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(Reg)) {
- if (AR->getLoop() == L)
- AddRecCost += 1; /// TODO: This should be a function of the stride.
-
// If this is an addrec for another loop, don't second-guess its addrec phi
// nodes. LSR isn't currently smart enough to reason about more than one
- // loop at a time. LSR has either already run on inner loops, will not run
- // on other loops, and cannot be expected to change sibling loops. If the
- // AddRec exists, consider it's register free and leave it alone. Otherwise,
- // do not consider this formula at all.
- else if (!EnableNested || L->contains(AR->getLoop()) ||
- (!AR->getLoop()->contains(L) &&
- DT.dominates(L->getHeader(), AR->getLoop()->getHeader()))) {
+ // loop at a time. LSR has already run on inner loops, will not run on outer
+ // loops, and cannot be expected to change sibling loops.
+ if (AR->getLoop() != L) {
+ // If the AddRec exists, consider it's register free and leave it alone.
if (isExistingPhi(AR, SE))
return;
- // For !EnableNested, never rewrite IVs in other loops.
- if (!EnableNested) {
- Loose();
- return;
- }
- // If this isn't one of the addrecs that the loop already has, it
- // would require a costly new phi and add. TODO: This isn't
- // precisely modeled right now.
- ++NumBaseAdds;
- if (!Regs.count(AR->getStart())) {
- RateRegister(AR->getStart(), Regs, L, SE, DT);
- if (isLoser())
- return;
- }
+ // Otherwise, do not consider this formula at all.
+ Loose();
+ return;
}
+ AddRecCost += 1; /// TODO: This should be a function of the stride.
// Add the step value register, if it needs one.
// TODO: The non-affine case isn't precisely modeled here.
@@ -2193,7 +2174,7 @@
do {
const SCEV *S = Worklist.pop_back_val();
if (const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(S)) {
- if (EnableNested || AR->getLoop() == L)
+ if (AR->getLoop() == L)
Strides.insert(AR->getStepRecurrence(SE));
Worklist.push_back(AR->getStart());
} else if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(S)) {
@@ -4566,7 +4547,7 @@
if (IU.empty()) return;
// Skip nested loops until we can model them better with formulae.
- if (!EnableNested && !L->empty()) {
+ if (!L->empty()) {
DEBUG(dbgs() << "LSR skipping outer loop " << *L << "\n");
return;
}