BreakCriticalEdges: Update PostDominatorTree
llvm-svn: 354673
diff --git a/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h b/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h
index e997ed0..a7bbe28 100644
--- a/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h
+++ b/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h
@@ -35,6 +35,7 @@
class MDNode;
class MemoryDependenceResults;
class MemorySSAUpdater;
+class PostDominatorTree;
class ReturnInst;
class TargetLibraryInfo;
class Value;
@@ -103,6 +104,7 @@
/// during critical edge splitting.
struct CriticalEdgeSplittingOptions {
DominatorTree *DT;
+ PostDominatorTree *PDT;
LoopInfo *LI;
MemorySSAUpdater *MSSAU;
bool MergeIdenticalEdges = false;
@@ -111,8 +113,9 @@
CriticalEdgeSplittingOptions(DominatorTree *DT = nullptr,
LoopInfo *LI = nullptr,
- MemorySSAUpdater *MSSAU = nullptr)
- : DT(DT), LI(LI), MSSAU(MSSAU) {}
+ MemorySSAUpdater *MSSAU = nullptr,
+ PostDominatorTree *PDT = nullptr)
+ : DT(DT), PDT(PDT), LI(LI), MSSAU(MSSAU) {}
CriticalEdgeSplittingOptions &setMergeIdenticalEdges() {
MergeIdenticalEdges = true;
diff --git a/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp b/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
index 2944c37..3b4b0b5 100644
--- a/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
+++ b/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
@@ -23,6 +23,7 @@
#include "llvm/Analysis/CFG.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/MemorySSAUpdater.h"
+#include "llvm/Analysis/PostDominators.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Instructions.h"
@@ -48,10 +49,14 @@
bool runOnFunction(Function &F) override {
auto *DTWP = getAnalysisIfAvailable<DominatorTreeWrapperPass>();
auto *DT = DTWP ? &DTWP->getDomTree() : nullptr;
+
+ auto *PDTWP = getAnalysisIfAvailable<PostDominatorTreeWrapperPass>();
+ auto *PDT = PDTWP ? &PDTWP->getPostDomTree() : nullptr;
+
auto *LIWP = getAnalysisIfAvailable<LoopInfoWrapperPass>();
auto *LI = LIWP ? &LIWP->getLoopInfo() : nullptr;
unsigned N =
- SplitAllCriticalEdges(F, CriticalEdgeSplittingOptions(DT, LI));
+ SplitAllCriticalEdges(F, CriticalEdgeSplittingOptions(DT, LI, nullptr, PDT));
NumBroken += N;
return N > 0;
}
@@ -201,16 +206,17 @@
// If we have nothing to update, just return.
auto *DT = Options.DT;
+ auto *PDT = Options.PDT;
auto *LI = Options.LI;
auto *MSSAU = Options.MSSAU;
if (MSSAU)
MSSAU->wireOldPredecessorsToNewImmediatePredecessor(
DestBB, NewBB, {TIBB}, Options.MergeIdenticalEdges);
- if (!DT && !LI)
+ if (!DT && !PDT && !LI)
return NewBB;
- if (DT) {
+ if (DT || PDT) {
// Update the DominatorTree.
// ---> NewBB -----\
// / V
@@ -226,7 +232,10 @@
if (llvm::find(successors(TIBB), DestBB) == succ_end(TIBB))
Updates.push_back({DominatorTree::Delete, TIBB, DestBB});
- DT->applyUpdates(Updates);
+ if (DT)
+ DT->applyUpdates(Updates);
+ if (PDT)
+ PDT->applyUpdates(Updates);
}
// Update LoopInfo if it is around.
diff --git a/llvm/unittests/Transforms/Utils/BasicBlockUtilsTest.cpp b/llvm/unittests/Transforms/Utils/BasicBlockUtilsTest.cpp
index db30837..2d3731c 100644
--- a/llvm/unittests/Transforms/Utils/BasicBlockUtilsTest.cpp
+++ b/llvm/unittests/Transforms/Utils/BasicBlockUtilsTest.cpp
@@ -7,6 +7,7 @@
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+#include "llvm/Analysis/PostDominators.h"
#include "llvm/AsmParser/Parser.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/Dominators.h"
@@ -49,3 +50,31 @@
SplitBlockPredecessors(&F->getEntryBlock(), {}, "split.entry", &DT);
EXPECT_TRUE(DT.verify());
}
+
+TEST(BasicBlockUtils, SplitCriticalEdge) {
+ LLVMContext C;
+
+ std::unique_ptr<Module> M = parseIR(
+ C,
+ "define void @crit_edge(i1 %cond0, i1 %cond1) {\n"
+ "entry:\n"
+ " br i1 %cond0, label %bb0, label %bb1\n"
+ "bb0:\n"
+ " br label %bb1\n"
+ "bb1:\n"
+ " br label %bb2\n"
+ "bb2:\n"
+ " ret void\n"
+ "}\n"
+ "\n"
+ );
+
+ auto *F = M->getFunction("crit_edge");
+ DominatorTree DT(*F);
+ PostDominatorTree PDT(*F);
+
+ CriticalEdgeSplittingOptions CESO(&DT, nullptr, nullptr, &PDT);
+ EXPECT_EQ(1u, SplitAllCriticalEdges(*F, CESO));
+ EXPECT_TRUE(DT.verify());
+ EXPECT_TRUE(PDT.verify());
+}
