[RISCV] Add RISCVISD::LD_RV32/SD_RV32 to isWorthFoldingAdd. (#151606)

Author: topperc

llvm/lib/Target/RISCV/RISCVISelDAGToDAG.cpp

@@ -2827,6 +2827,8 @@ static bool selectConstantAddr(SelectionDAG *CurDAG, const SDLoc &DL,
 static bool isWorthFoldingAdd(SDValue Add) {
   for (auto *User : Add->users()) {
     if (User->getOpcode() != ISD::LOAD && User->getOpcode() != ISD::STORE &&
+        User->getOpcode() != RISCVISD::LD_RV32 &&
+        User->getOpcode() != RISCVISD::SD_RV32 &&
         User->getOpcode() != ISD::ATOMIC_LOAD &&
         User->getOpcode() != ISD::ATOMIC_STORE)
       return false;
@@ -2841,6 +2843,9 @@ static bool isWorthFoldingAdd(SDValue Add) {
     if (User->getOpcode() == ISD::ATOMIC_STORE &&
         cast<AtomicSDNode>(User)->getVal() == Add)
       return false;
+    if (User->getOpcode() == RISCVISD::SD_RV32 &&
+        (User->getOperand(0) == Add || User->getOperand(1) == Add))
+      return false;
     if (isStrongerThanMonotonic(cast<MemSDNode>(User)->getSuccessOrdering()))
       return false;
   }

llvm/test/CodeGen/RISCV/zilsd.ll

@@ -117,3 +117,22 @@ entyr:
   store i64 0, ptr @g
   ret void
 }
+
+define void @large_offset(ptr nocapture %p, i64 %d) nounwind {
+; CHECK-LABEL: large_offset:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    lui a1, 4
+; CHECK-NEXT:    add a0, a0, a1
+; CHECK-NEXT:    ld a2, -384(a0)
+; CHECK-NEXT:    addi a2, a2, 1
+; CHECK-NEXT:    seqz a1, a2
+; CHECK-NEXT:    add a3, a3, a1
+; CHECK-NEXT:    sd a2, -384(a0)
+; CHECK-NEXT:    ret
+entry:
+  %add.ptr = getelementptr inbounds i64, ptr %p, i64 2000
+  %a = load i64, ptr %add.ptr, align 8
+  %b = add i64 %a, 1
+  store i64 %b, ptr %add.ptr, align 8
+  ret void
+}