[JumpThread] Enhance finding partial redundant loads by continuing scanning single predecessor
Summary: While scanning predecessors to find an available loaded value, if the predecessor has a single predecessor, we can continue scanning through the single predecessor.
Reviewers: mcrosier, rengolin, reames, davidxl, haicheng
Reviewed By: rengolin
Subscribers: zzheng, llvm-commits
Differential Revision: https://reviews.llvm.org/D29200
llvm-svn: 293896
diff --git a/llvm/lib/Analysis/Loads.cpp b/llvm/lib/Analysis/Loads.cpp
index e46541e..5d842db 100644
--- a/llvm/lib/Analysis/Loads.cpp
+++ b/llvm/lib/Analysis/Loads.cpp
@@ -312,7 +312,8 @@
BasicBlock *ScanBB,
BasicBlock::iterator &ScanFrom,
unsigned MaxInstsToScan,
- AliasAnalysis *AA, bool *IsLoadCSE) {
+ AliasAnalysis *AA, bool *IsLoadCSE,
+ unsigned *NumScanedInst) {
if (MaxInstsToScan == 0)
MaxInstsToScan = ~0U;
@@ -344,6 +345,9 @@
// Restore ScanFrom to expected value in case next test succeeds
ScanFrom++;
+ if (NumScanedInst)
+ ++(*NumScanedInst);
+
// Don't scan huge blocks.
if (MaxInstsToScan-- == 0)
return nullptr;