}
}
+ // Fold a series of buildvector, bitcast, and truncate if possible.
+ // For example fold
+ // (2xi32 trunc (bitcast ((4xi32)buildvector x, x, y, y) 2xi64)) to
+ // (2xi32 (buildvector x, y)).
+ if (Level == AfterLegalizeVectorOps && VT.isVector() &&
+ N0.getOpcode() == ISD::BITCAST && N0.hasOneUse() &&
+ N0.getOperand(0).getOpcode() == ISD::BUILD_VECTOR &&
+ N0.getOperand(0).hasOneUse()) {
+
+ SDValue BuildVect = N0.getOperand(0);
+ EVT BuildVectEltTy = BuildVect.getValueType().getVectorElementType();
+ EVT TruncVecEltTy = VT.getVectorElementType();
+
+ // Check that the element types match.
+ if (BuildVectEltTy == TruncVecEltTy) {
+ // Now we only need to compute the offset of the truncated elements.
+ unsigned BuildVecNumElts = BuildVect.getNumOperands();
+ unsigned TruncVecNumElts = VT.getVectorNumElements();
+ unsigned TruncEltOffset = BuildVecNumElts / TruncVecNumElts;
+
+ assert((BuildVecNumElts % TruncVecNumElts) == 0 &&
+ "Invalid number of elements");
+
+ SmallVector<SDValue, 8> Opnds;
+ for (unsigned i = 0, e = BuildVecNumElts; i != e; i += TruncEltOffset)
+ Opnds.push_back(BuildVect.getOperand(i));
+
+ return DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), VT, &Opnds[0],
+ Opnds.size());
+ }
+ }
+
// See if we can simplify the input to this truncate through knowledge that
// only the low bits are being used.
// For example "trunc (or (shl x, 8), y)" // -> trunc y
--- /dev/null
+; RUN: llc < %s -march=arm -mcpu=cortex-a9 | FileCheck %s
+; bug 15283
+; radar://13191881
+; CHECK: vfcmp
+define void @vfcmp(<2 x double>* %a, <2 x double>* %b) {
+ %wide.load = load <2 x double>* %a, align 4
+ %wide.load2 = load <2 x double>* %b, align 4
+; CHECK-NOT: vdup.32
+; CHECK-NOT: vmovn.i64
+ %v1 = fcmp olt <2 x double> %wide.load, %wide.load2
+ %v2 = zext <2 x i1> %v1 to <2 x i32>
+ %v3 = sitofp <2 x i32> %v2 to <2 x double>
+ store <2 x double> %v3, <2 x double>* %b, align 4
+ ret void
+}