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authorChris Lattner <sabre@nondot.org>2009-03-06 05:34:10 +0000
committerChris Lattner <sabre@nondot.org>2009-03-06 05:34:10 +0000
commitcc14d25dd99e891c586bd56aa41796abbe4ac3d8 (patch)
treefcc5b45f79eaf1d6db4860bcf6e0771d3022c24b /lib/Transforms/Scalar/JumpThreading.cpp
parent3f43a7021fae71c056f5e1afc60016cfd8193f68 (diff)
Change various llvm utilities to use PrettyStackTraceProgram in
their main routines. This makes the tools print their argc/argv commands if they crash. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66248 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Transforms/Scalar/JumpThreading.cpp')
-rw-r--r--lib/Transforms/Scalar/JumpThreading.cpp34
1 files changed, 34 insertions, 0 deletions
diff --git a/lib/Transforms/Scalar/JumpThreading.cpp b/lib/Transforms/Scalar/JumpThreading.cpp
index f96fc208ae..1f3e6b11c8 100644
--- a/lib/Transforms/Scalar/JumpThreading.cpp
+++ b/lib/Transforms/Scalar/JumpThreading.cpp
@@ -407,6 +407,12 @@ bool JumpThreading::ProcessBranchOnDuplicateCond(BasicBlock *PredBB,
return true;
}
+struct APIntUnsignedOrdering {
+ bool operator()(const APInt &LHS, const APInt &RHS) const {
+ return LHS.ult(RHS);
+ }
+};
+
/// ProcessSwitchOnDuplicateCond - We found a block and a predecessor of that
/// block that switch on exactly the same condition. This means that we almost
/// always know the direction of the edge in the DESTBB:
@@ -474,6 +480,34 @@ bool JumpThreading::ProcessSwitchOnDuplicateCond(BasicBlock *PredBB,
return true;
}
+#if 0
+ // Figure out on which of the condition allow us to get to DESTBB. If DESTBB
+ // is the default label, we compute the set of values COND is known not to be
+ // otherwise we compute the set of options that COND could be.
+ SmallVector<APInt, 16> KnownValues;
+ bool DestBBIsDefault = PredSI->getSuccessor(0) == DestBB;
+
+ if (DestBBIsDefault) {
+ // DestBB the default case. Collect the values where PredBB can't branch to
+ // DestBB.
+ for (unsigned i = 1/*skip default*/, e = PredSI->getNumCases(); i != e; ++i)
+ if (PredSI->getSuccessor(i) != DestBB)
+ KnownValues.push_back(PredSI->getCaseValue(i)->getValue());
+ } else {
+ // Not the default case. Collect the values where PredBB can branch to
+ // DestBB.
+ for (unsigned i = 1/*skip default*/, e = PredSI->getNumCases(); i != e; ++i)
+ if (PredSI->getSuccessor(i) == DestBB)
+ KnownValues.push_back(PredSI->getCaseValue(i)->getValue());
+ }
+
+ std::sort(KnownValues.begin(), KnownValues.end(), APIntUnsignedOrdering());
+ return false;
+ cerr << "\nFOUND THREAD BLOCKS:\n";
+ PredBB->dump();
+ DestBB->dump();
+#endif
+
return false;
}