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authorDavid Majnemer <david.majnemer@gmail.com>2013-04-18 08:42:33 +0000
committerDavid Majnemer <david.majnemer@gmail.com>2013-04-18 08:42:33 +0000
commit7754276c4cd257991949231113afa46613c0fdbb (patch)
tree52ee4c83f19137ad18305a7edf6c58e6cfb8152d /lib
parenta40a3a59818d1fe394f23cda1df940762e30ea65 (diff)
Revert "Combine bit test + conditional or into simple math"
It is causing stage2 builds to fail, let's get them running again. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179750 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib')
-rw-r--r--lib/Transforms/InstCombine/InstCombineSelect.cpp61
1 files changed, 0 insertions, 61 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineSelect.cpp b/lib/Transforms/InstCombine/InstCombineSelect.cpp
index f5a33bad295..f0738b48cbb 100644
--- a/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ b/lib/Transforms/InstCombine/InstCombineSelect.cpp
@@ -350,64 +350,6 @@ static Value *SimplifyWithOpReplaced(Value *V, Value *Op, Value *RepOp,
return 0;
}
-/// foldSelectICmpAndOr - We want to turn:
-/// (select (icmp eq (and X, C1), 0), Y, (or Y, C2))
-/// into:
-/// (or (shl (and X, C1), C3), y)
-/// iff:
-/// C1 and C2 are both powers of 2
-/// where:
-/// C3 = Log(C2) - Log(C1)
-///
-/// This transform handles cases where:
-/// 1. The icmp predicate is inverted
-/// 2. The select operands are reversed
-/// 3. The magnitude of C2 and C1 are flipped
-static Value *foldSelectICmpAndOr(const SelectInst &SI, Value *TrueVal,
- Value *FalseVal,
- InstCombiner::BuilderTy *Builder) {
- const ICmpInst *IC = dyn_cast<ICmpInst>(SI.getCondition());
- if (!IC || !IC->isEquality())
- return 0;
-
- Value *CmpLHS = IC->getOperand(0);
- Value *CmpRHS = IC->getOperand(1);
-
- if (!match(CmpRHS, m_Zero()))
- return 0;
-
- Value *X;
- const APInt *C1;
- if (!match(CmpLHS, m_And(m_Value(X), m_Power2(C1))))
- return 0;
-
- const APInt *C2;
- bool OrOnTrueVal = false;
- bool OrOnFalseVal = match(FalseVal, m_Or(m_Specific(TrueVal), m_Power2(C2)));
- if (!OrOnFalseVal)
- OrOnTrueVal = match(TrueVal, m_Or(m_Specific(FalseVal), m_Power2(C2)));
-
- if (!OrOnFalseVal && !OrOnTrueVal)
- return 0;
-
- Value *V = CmpLHS;
-
- unsigned C1Log = C1->logBase2();
- unsigned C2Log = C2->logBase2();
- if (C2Log > C1Log)
- V = Builder->CreateShl(V, C2Log - C1Log);
- else if (C1Log > C2Log)
- V = Builder->CreateLShr(V, C1Log - C2Log);
-
- ICmpInst::Predicate Pred = IC->getPredicate();
- if ((Pred == ICmpInst::ICMP_NE && OrOnFalseVal) ||
- (Pred == ICmpInst::ICMP_EQ && OrOnTrueVal))
- V = Builder->CreateXor(V, *C2);
-
- Value *Y = OrOnFalseVal ? TrueVal : FalseVal;
- return Builder->CreateOr(V, Y);
-}
-
/// visitSelectInstWithICmp - Visit a SelectInst that has an
/// ICmpInst as its first operand.
///
@@ -579,9 +521,6 @@ Instruction *InstCombiner::visitSelectInstWithICmp(SelectInst &SI,
}
}
- if (Value *V = foldSelectICmpAndOr(SI, TrueVal, FalseVal, Builder))
- return ReplaceInstUsesWith(SI, V);
-
return Changed ? &SI : 0;
}