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| author | dim <dim@FreeBSD.org> | 2014-11-27 00:33:31 +0000 |
|---|---|---|
| committer | dim <dim@FreeBSD.org> | 2014-11-27 00:33:31 +0000 |
| commit | d0207f44e28d1c2f2507707b19ab45fb8219eed4 (patch) | |
| tree | 260ff8868f69c15380ec28da42ca50f4e6acc937 /contrib/llvm/lib/Transforms | |
| parent | 226a2bb6bfbe23e6d7982d86aacac4e7231b17e3 (diff) | |
| download | FreeBSD-src-d0207f44e28d1c2f2507707b19ab45fb8219eed4.zip FreeBSD-src-d0207f44e28d1c2f2507707b19ab45fb8219eed4.tar.gz | |
Pull in r222856 from upstream llvm trunk (by David Majnemer):
Revert "Added inst combine transforms for single bit tests from Chris's note"
This reverts commit r210006, it miscompiled libapr which is used in who
knows how many projects.
A test has been added to ensure that we don't regress again.
This fixes a miscompilation in libapr, which caused problems in svnlite.
Diffstat (limited to 'contrib/llvm/lib/Transforms')
| -rw-r--r-- | contrib/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp | 29 |
1 files changed, 1 insertions, 28 deletions
diff --git a/contrib/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/contrib/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp index 06c9e29..a36cbe6 100644 --- a/contrib/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp +++ b/contrib/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp @@ -387,15 +387,7 @@ static Value *SimplifyWithOpReplaced(Value *V, Value *Op, Value *RepOp, /// 1. The icmp predicate is inverted /// 2. The select operands are reversed /// 3. The magnitude of C2 and C1 are flipped -/// -/// This also tries to turn -/// --- Single bit tests: -/// if ((x & C) == 0) x |= C to x |= C -/// if ((x & C) != 0) x ^= C to x &= ~C -/// if ((x & C) == 0) x ^= C to x |= C -/// if ((x & C) != 0) x &= ~C to x &= ~C -/// if ((x & C) == 0) x &= ~C to nothing -static Value *foldSelectICmpAndOr(SelectInst &SI, Value *TrueVal, +static Value *foldSelectICmpAndOr(const SelectInst &SI, Value *TrueVal, Value *FalseVal, InstCombiner::BuilderTy *Builder) { const ICmpInst *IC = dyn_cast<ICmpInst>(SI.getCondition()); @@ -414,25 +406,6 @@ static Value *foldSelectICmpAndOr(SelectInst &SI, Value *TrueVal, return nullptr; const APInt *C2; - if (match(TrueVal, m_Specific(X))) { - // if ((X & C) != 0) X ^= C becomes X &= ~C - if (match(FalseVal, m_Xor(m_Specific(X), m_APInt(C2))) && C1 == C2) - return Builder->CreateAnd(X, ~(*C1)); - // if ((X & C) != 0) X &= ~C becomes X &= ~C - if (match(FalseVal, m_And(m_Specific(X), m_APInt(C2))) && *C1 == ~(*C2)) - return FalseVal; - } else if (match(FalseVal, m_Specific(X))) { - // if ((X & C) == 0) X ^= C becomes X |= C - if (match(TrueVal, m_Xor(m_Specific(X), m_APInt(C2))) && C1 == C2) - return Builder->CreateOr(X, *C1); - // if ((X & C) == 0) X &= ~C becomes nothing - if (match(TrueVal, m_And(m_Specific(X), m_APInt(C2))) && *C1 == ~(*C2)) - return X; - // if ((X & C) == 0) X |= C becomes X |= C - if (match(TrueVal, m_Or(m_Specific(X), m_APInt(C2))) && C1 == C2) - return TrueVal; - } - bool OrOnTrueVal = false; bool OrOnFalseVal = match(FalseVal, m_Or(m_Specific(TrueVal), m_Power2(C2))); if (!OrOnFalseVal) |
