Add a method to ScalarEvolution for telling it when a loop has been
modified in a way that may effect the trip count calculation. Change
IndVars to use this method when it rewrites pointer or floating-point
induction variables instead of using a doInitialization method to
sneak these changes in before ScalarEvolution has a chance to see
the loop. This eliminates the need for LoopPass to depend on
ScalarEvolution.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64810 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 4e0dba7..54f27653 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -1453,6 +1453,11 @@
/// an analyzable loop-invariant iteration count.
bool hasLoopInvariantIterationCount(const Loop *L);
+ /// forgetLoopIterationCount - This method should be called by the
+ /// client when it has changed a loop in a way that may effect
+ /// ScalarEvolution's ability to compute a trip count.
+ void forgetLoopIterationCount(const Loop *L);
+
/// getIterationCount - If the specified loop has a predictable iteration
/// count, return it. Note that it is not valid to call this method on a
/// loop without a loop-invariant iteration count.
@@ -1931,6 +1936,13 @@
return I->second;
}
+/// forgetLoopIterationCount - This method should be called by the
+/// client when it has changed a loop in a way that may effect
+/// ScalarEvolution's ability to compute a trip count.
+void ScalarEvolutionsImpl::forgetLoopIterationCount(const Loop *L) {
+ IterationCounts.erase(L);
+}
+
/// ComputeIterationCount - Compute the number of times the specified loop
/// will iterate.
SCEVHandle ScalarEvolutionsImpl::ComputeIterationCount(const Loop *L) {
@@ -3091,6 +3103,10 @@
return !isa<SCEVCouldNotCompute>(getIterationCount(L));
}
+void ScalarEvolution::forgetLoopIterationCount(const Loop *L) {
+ return ((ScalarEvolutionsImpl*)Impl)->forgetLoopIterationCount(L);
+}
+
SCEVHandle ScalarEvolution::getSCEVAtScope(Value *V, const Loop *L) const {
return ((ScalarEvolutionsImpl*)Impl)->getSCEVAtScope(getSCEV(V), L);
}