+ConstantRange ConstantRange::makeICmpRegion(unsigned Pred,
+ const ConstantRange &CR) {
+ if (CR.isEmptySet())
+ return CR;
+
+ uint32_t W = CR.getBitWidth();
+ switch (Pred) {
+ default: assert(!"Invalid ICmp predicate to makeICmpRegion()");
+ case CmpInst::ICMP_EQ:
+ return CR;
+ case CmpInst::ICMP_NE:
+ if (CR.isSingleElement())
+ return ConstantRange(CR.getUpper(), CR.getLower());
+ return ConstantRange(W);
+ case CmpInst::ICMP_ULT: {
+ APInt UMax(CR.getUnsignedMax());
+ if (UMax.isMinValue())
+ return ConstantRange(W, /* empty */ false);
+ return ConstantRange(APInt::getMinValue(W), UMax);
+ }
+ case CmpInst::ICMP_SLT: {
+ APInt SMax(CR.getSignedMax());
+ if (SMax.isMinSignedValue())
+ return ConstantRange(W, /* empty */ false);
+ return ConstantRange(APInt::getSignedMinValue(W), SMax);
+ }
+ case CmpInst::ICMP_ULE: {
+ APInt UMax(CR.getUnsignedMax());
+ if (UMax.isMaxValue())
+ return ConstantRange(W);
+ return ConstantRange(APInt::getMinValue(W), UMax + 1);
+ }
+ case CmpInst::ICMP_SLE: {
+ APInt SMax(CR.getSignedMax());
+ if (SMax.isMaxSignedValue())
+ return ConstantRange(W);
+ return ConstantRange(APInt::getSignedMinValue(W), SMax + 1);
+ }
+ case CmpInst::ICMP_UGT: {
+ APInt UMin(CR.getUnsignedMin());
+ if (UMin.isMaxValue())
+ return ConstantRange(W, /* empty */ false);
+ return ConstantRange(UMin + 1, APInt::getNullValue(W));
+ }
+ case CmpInst::ICMP_SGT: {
+ APInt SMin(CR.getSignedMin());
+ if (SMin.isMaxSignedValue())
+ return ConstantRange(W, /* empty */ false);
+ return ConstantRange(SMin + 1, APInt::getSignedMinValue(W));
+ }
+ case CmpInst::ICMP_UGE: {
+ APInt UMin(CR.getUnsignedMin());
+ if (UMin.isMinValue())
+ return ConstantRange(W);
+ return ConstantRange(UMin, APInt::getNullValue(W));
+ }
+ case CmpInst::ICMP_SGE: {
+ APInt SMin(CR.getSignedMin());
+ if (SMin.isMinSignedValue())
+ return ConstantRange(W);
+ return ConstantRange(SMin, APInt::getSignedMinValue(W));
+ }
+ }
+}
+