Explicitly match all the cases

Author: nikic

llvm/include/llvm/IR/PatternMatch.h

@@ -2111,28 +2111,6 @@ template <typename Op_t> struct PtrToIntSameSize_match {
   }
 };
 
-template <typename Op_t> struct PtrToIntOrAddr_GEAddrSize_match {
-  const DataLayout &DL;
-  Op_t Op;
-
-  PtrToIntOrAddr_GEAddrSize_match(const DataLayout &DL, const Op_t &OpMatch)
-      : DL(DL), Op(OpMatch) {}
-
-  template <typename OpTy> bool match(OpTy *V) const {
-    if (auto *O = dyn_cast<Operator>(V)) {
-      unsigned Opcode = O->getOpcode();
-      // The ptrtoaddr result type always matches the address size.
-      // For ptrtoint we have to explicitly check it.
-      return (Opcode == Instruction::PtrToAddr ||
-              (Opcode == Instruction::PtrToInt &&
-               O->getType()->getScalarSizeInBits() >=
-                   DL.getAddressSizeInBits(O->getOperand(0)->getType()))) &&
-             Op.match(O->getOperand(0));
-    }
-    return false;
-  }
-};
-
 template <typename Op_t> struct NNegZExt_match {
   Op_t Op;
 
@@ -2218,14 +2196,6 @@ template <typename OpTy> inline auto m_PtrToIntOrAddr(const OpTy &Op) {
   return m_CombineOr(m_PtrToInt(Op), m_PtrToAddr(Op));
 }
 
-/// Matches PtrToInt or PtrToAddr where the result is greater than or equal
-/// to the pointer address size.
-template <typename OpTy>
-inline PtrToIntOrAddr_GEAddrSize_match<OpTy>
-m_PtrToIntOrAddr_GEAddrSize(const DataLayout &DL, const OpTy &Op) {
-  return PtrToIntOrAddr_GEAddrSize_match<OpTy>(DL, Op);
-}
-
 /// Matches IntToPtr.
 template <typename OpTy>
 inline CastOperator_match<OpTy, Instruction::IntToPtr>

llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp

@@ -2773,9 +2773,21 @@ Instruction *InstCombinerImpl::visitSub(BinaryOperator &I) {
                                                /* IsNUW */ false))
       return replaceInstUsesWith(I, Res);
 
-  if (match(Op0, m_ZExt(m_PtrToIntOrAddr_GEAddrSize(DL, m_Value(LHSOp)))) &&
-      match(Op1,
-            m_ZExtOrSelf(m_PtrToIntOrAddr_GEAddrSize(DL, m_Value(RHSOp))))) {
+  auto MatchSubOfZExtOfPtrToIntOrAddr = [&]() {
+    if (match(Op0, m_ZExt(m_PtrToIntSameSize(DL, m_Value(LHSOp)))) &&
+        match(Op1, m_ZExt(m_PtrToIntSameSize(DL, m_Value(RHSOp)))))
+      return true;
+    if (match(Op0, m_ZExt(m_PtrToAddr(m_Value(LHSOp)))) &&
+        match(Op1, m_ZExt(m_PtrToAddr(m_Value(RHSOp)))))
+      return true;
+    // Special case for non-canonical ptrtoint in constant expression,
+    // where the zext has been folded into the ptrtoint.
+    if (match(Op0, m_ZExt(m_PtrToIntSameSize(DL, m_Value(LHSOp)))) &&
+        match(Op1, m_PtrToInt(m_Value(RHSOp))))
+      return true;
+    return false;
+  };
+  if (MatchSubOfZExtOfPtrToIntOrAddr()) {
     if (auto *GEP = dyn_cast<GEPOperator>(LHSOp)) {
       if (GEP->getPointerOperand() == RHSOp) {
         if (GEP->hasNoUnsignedWrap() || GEP->hasNoUnsignedSignedWrap()) {