[DAGCombiner] Unify Lifetime and memory Op aliasing.
Rework BaseIndexOffset and isAlias to fully work with lifetime nodes
and fold in lifetime alias analysis.
This is mostly NFC.
Reviewers: courbet
Reviewed By: courbet
Subscribers: hiraditya, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59794
llvm-svn: 357070
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGAddressAnalysis.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGAddressAnalysis.cpp
index f5adfa5..9592bc3 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGAddressAnalysis.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGAddressAnalysis.cpp
@@ -24,8 +24,10 @@
// Conservatively fail if we a match failed..
if (!Base.getNode() || !Other.Base.getNode())
return false;
+ if (!hasValidOffset() || !Other.hasValidOffset())
+ return false;
// Initial Offset difference.
- Off = Other.Offset - Offset;
+ Off = *Other.Offset - *Offset;
if ((Other.Index == Index) && (Other.IsIndexSignExt == IsIndexSignExt)) {
// Trivial match.
@@ -79,26 +81,31 @@
return false;
}
-bool BaseIndexOffset::computeAliasing(const BaseIndexOffset &BasePtr0,
- const int64_t NumBytes0,
- const BaseIndexOffset &BasePtr1,
- const int64_t NumBytes1,
+bool BaseIndexOffset::computeAliasing(const SDNode *Op0,
+ const Optional<int64_t> NumBytes0,
+ const SDNode *Op1,
+ const Optional<int64_t> NumBytes1,
const SelectionDAG &DAG, bool &IsAlias) {
+
+ BaseIndexOffset BasePtr0 = match(Op0, DAG);
+ BaseIndexOffset BasePtr1 = match(Op1, DAG);
+
if (!(BasePtr0.getBase().getNode() && BasePtr1.getBase().getNode()))
return false;
int64_t PtrDiff;
- if (BasePtr0.equalBaseIndex(BasePtr1, DAG, PtrDiff)) {
+ if (NumBytes0.hasValue() && NumBytes1.hasValue() &&
+ BasePtr0.equalBaseIndex(BasePtr1, DAG, PtrDiff)) {
// BasePtr1 is PtrDiff away from BasePtr0. They alias if none of the
// following situations arise:
IsAlias = !(
// [----BasePtr0----]
// [---BasePtr1--]
// ========PtrDiff========>
- (NumBytes0 <= PtrDiff) ||
+ (*NumBytes0 <= PtrDiff) ||
// [----BasePtr0----]
// [---BasePtr1--]
// =====(-PtrDiff)====>
- (PtrDiff + NumBytes1 <= 0)); // i.e. NumBytes1 < -PtrDiff.
+ (PtrDiff + *NumBytes1 <= 0)); // i.e. *NumBytes1 < -PtrDiff.
return true;
}
// If both BasePtr0 and BasePtr1 are FrameIndexes, we will not be
@@ -156,8 +163,8 @@
}
/// Parses tree in Ptr for base, index, offset addresses.
-BaseIndexOffset BaseIndexOffset::match(const LSBaseSDNode *N,
- const SelectionDAG &DAG) {
+static BaseIndexOffset matchLSNode(const LSBaseSDNode *N,
+ const SelectionDAG &DAG) {
SDValue Ptr = N->getBasePtr();
// (((B + I*M) + c)) + c ...
@@ -259,6 +266,18 @@
return BaseIndexOffset(Base, Index, Offset, IsIndexSignExt);
}
+BaseIndexOffset BaseIndexOffset::match(const SDNode *N,
+ const SelectionDAG &DAG) {
+ if (const auto *LS0 = dyn_cast<LSBaseSDNode>(N))
+ return matchLSNode(LS0, DAG);
+ if (const auto *LN = dyn_cast<LifetimeSDNode>(N)) {
+ if (LN->hasOffset())
+ return BaseIndexOffset(LN->getOperand(1), SDValue(), LN->getOffset(),
+ false);
+ return BaseIndexOffset(LN->getOperand(1), SDValue(), false);
+ }
+ return BaseIndexOffset();
+}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)