From ceb9a959573b102d0fc7776cf4660881e6f0f628 Mon Sep 17 00:00:00 2001 From: Owen Anderson Date: Thu, 16 Sep 2010 18:35:07 +0000 Subject: Use a depth-first iteratation in CorrelatedValuePropagation to avoid wasting time trying to optimize unreachable blocks. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114105 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/CorrelatedValuePropagation.cpp | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'lib/Transforms/Scalar/CorrelatedValuePropagation.cpp') diff --git a/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp b/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp index 0d4e45de34..e8b8e94617 100644 --- a/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp +++ b/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp @@ -19,6 +19,7 @@ #include "llvm/Analysis/LazyValueInfo.h" #include "llvm/Support/CFG.h" #include "llvm/Transforms/Utils/Local.h" +#include "llvm/ADT/DepthFirstIterator.h" #include "llvm/ADT/Statistic.h" using namespace llvm; @@ -166,7 +167,10 @@ bool CorrelatedValuePropagation::runOnFunction(Function &F) { bool FnChanged = false; - for (Function::iterator FI = F.begin(), FE = F.end(); FI != FE; ++FI) { + // Perform a depth-first walk of the CFG so that we don't waste time + // optimizing unreachable blocks. + for (df_iterator FI = df_begin(&F.getEntryBlock()), + FE = df_end(&F.getEntryBlock()); FI != FE; ++FI) { bool BBChanged = false; for (BasicBlock::iterator BI = FI->begin(), BE = FI->end(); BI != BE; ) { Instruction *II = BI++; @@ -191,7 +195,7 @@ bool CorrelatedValuePropagation::runOnFunction(Function &F) { // Propagating correlated values might leave cruft around. // Try to clean it up before we continue. if (BBChanged) - SimplifyInstructionsInBlock(FI); + SimplifyInstructionsInBlock(*FI); FnChanged |= BBChanged; } -- cgit v1.2.3