X86: Introduce relocImm-based patterns for cmp.
Differential Revision: https://reviews.llvm.org/D28690
llvm-svn: 294636
diff --git a/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp b/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
index 7f08d2d..b19e410 100644
--- a/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -384,6 +384,16 @@
bool ComplexPatternFuncMutatesDAG() const override {
return true;
}
+
+ bool isSExtAbsoluteSymbolRef(unsigned Width, SDNode *N) const;
+
+ /// Returns whether this is a relocatable immediate in the range
+ /// [-2^Width .. 2^Width-1].
+ template <unsigned Width> bool isSExtRelocImm(SDNode *N) const {
+ if (auto *CN = dyn_cast<ConstantSDNode>(N))
+ return isInt<Width>(CN->getSExtValue());
+ return isSExtAbsoluteSymbolRef(Width, N);
+ }
};
}
@@ -1789,6 +1799,21 @@
return CurDAG->getRegister(GlobalBaseReg, TLI->getPointerTy(DL)).getNode();
}
+bool X86DAGToDAGISel::isSExtAbsoluteSymbolRef(unsigned Width, SDNode *N) const {
+ if (N->getOpcode() == ISD::TRUNCATE)
+ N = N->getOperand(0).getNode();
+ if (N->getOpcode() != X86ISD::Wrapper)
+ return false;
+
+ auto *GA = dyn_cast<GlobalAddressSDNode>(N->getOperand(0));
+ if (!GA)
+ return false;
+
+ Optional<ConstantRange> CR = GA->getGlobal()->getAbsoluteSymbolRange();
+ return CR && CR->getSignedMin().sge(-1ull << Width) &&
+ CR->getSignedMax().slt(1ull << Width);
+}
+
/// Test whether the given X86ISD::CMP node has any uses which require the SF
/// or OF bits to be accurate.
static bool hasNoSignedComparisonUses(SDNode *N) {