diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -3271,6 +3271,7 @@
       Known.Zero.setBitsFrom(1);
     break;
   case ISD::SETCC:
+  case ISD::SETCCCARRY:
   case ISD::STRICT_FSETCC:
   case ISD::STRICT_FSETCCS: {
     unsigned OpNo = Op->isStrictFPOpcode() ? 1 : 0;
@@ -3506,6 +3507,8 @@
     break;
   case ISD::USUBO:
   case ISD::SSUBO:
+  case ISD::SUBCARRY:
+  case ISD::SSUBO_CARRY:
     if (Op.getResNo() == 1) {
       // If we know the result of a setcc has the top bits zero, use this info.
       if (TLI->getBooleanContents(Op.getOperand(0).getValueType()) ==
@@ -3520,6 +3523,10 @@
     assert(Op.getResNo() == 0 &&
            "We only compute knownbits for the difference here.");
 
+    // TODO: Compute influence of the carry operand.
+    if (Opcode == ISD::SUBCARRY || Opcode == ISD::SSUBO_CARRY)
+      break;
+
     Known = computeKnownBits(Op.getOperand(0), DemandedElts, Depth + 1);
     Known2 = computeKnownBits(Op.getOperand(1), DemandedElts, Depth + 1);
     Known = KnownBits::computeForAddSub(/* Add */ false, /* NSW */ false,
@@ -3529,6 +3536,7 @@
   case ISD::UADDO:
   case ISD::SADDO:
   case ISD::ADDCARRY:
+  case ISD::SADDO_CARRY:
     if (Op.getResNo() == 1) {
       // If we know the result of a setcc has the top bits zero, use this info.
       if (TLI->getBooleanContents(Op.getOperand(0).getValueType()) ==
@@ -3548,7 +3556,7 @@
     if (Opcode == ISD::ADDE)
       // Can't track carry from glue, set carry to unknown.
       Carry.resetAll();
-    else if (Opcode == ISD::ADDCARRY)
+    else if (Opcode == ISD::ADDCARRY || Opcode == ISD::SADDO_CARRY)
       // TODO: Compute known bits for the carry operand. Not sure if it is worth
       // the trouble (how often will we find a known carry bit). And I haven't
       // tested this very much yet, but something like this might work:
@@ -4108,8 +4116,12 @@
     return std::min(Tmp, Tmp2);
   case ISD::SADDO:
   case ISD::UADDO:
+  case ISD::SADDO_CARRY:
+  case ISD::ADDCARRY:
   case ISD::SSUBO:
   case ISD::USUBO:
+  case ISD::SSUBO_CARRY:
+  case ISD::SUBCARRY:
   case ISD::SMULO:
   case ISD::UMULO:
     if (Op.getResNo() != 1)
@@ -4123,6 +4135,7 @@
       return VTBits;
     break;
   case ISD::SETCC:
+  case ISD::SETCCCARRY:
   case ISD::STRICT_FSETCC:
   case ISD::STRICT_FSETCCS: {
     unsigned OpNo = Op->isStrictFPOpcode() ? 1 : 0;
diff --git a/llvm/test/CodeGen/AArch64/i256-math.ll b/llvm/test/CodeGen/AArch64/i256-math.ll
--- a/llvm/test/CodeGen/AArch64/i256-math.ll
+++ b/llvm/test/CodeGen/AArch64/i256-math.ll
@@ -98,11 +98,7 @@
 ; CHECK:       // %bb.0:
 ; CHECK-NEXT:    subs x0, x0, x4
 ; CHECK-NEXT:    sbcs x1, x1, x5
-; CHECK-NEXT:    cset w8, lo
-; CHECK-NEXT:    cmp wzr, w8
 ; CHECK-NEXT:    sbcs x2, x2, x6
-; CHECK-NEXT:    cset w8, lo
-; CHECK-NEXT:    cmp wzr, w8
 ; CHECK-NEXT:    sbcs x3, x3, x7
 ; CHECK-NEXT:    cset w8, lo
 ; CHECK-NEXT:    eor w4, w8, #0x1
@@ -122,11 +118,7 @@
 ; CHECK:       // %bb.0:
 ; CHECK-NEXT:    subs x0, x0, x4
 ; CHECK-NEXT:    sbcs x1, x1, x5
-; CHECK-NEXT:    cset w8, lo
-; CHECK-NEXT:    cmp wzr, w8
 ; CHECK-NEXT:    sbcs x2, x2, x6
-; CHECK-NEXT:    cset w8, lo
-; CHECK-NEXT:    cmp wzr, w8
 ; CHECK-NEXT:    sbcs x3, x3, x7
 ; CHECK-NEXT:    cset w4, lo
 ; CHECK-NEXT:    ret
@@ -244,11 +236,7 @@
 ; CHECK:       // %bb.0:
 ; CHECK-NEXT:    subs x0, x0, x4
 ; CHECK-NEXT:    sbcs x1, x1, x5
-; CHECK-NEXT:    cset w8, lo
-; CHECK-NEXT:    cmp wzr, w8
 ; CHECK-NEXT:    sbcs x2, x2, x6
-; CHECK-NEXT:    cset w8, lo
-; CHECK-NEXT:    cmp wzr, w8
 ; CHECK-NEXT:    sbcs x3, x3, x7
 ; CHECK-NEXT:    cset w8, vs
 ; CHECK-NEXT:    eor w4, w8, #0x1
@@ -268,11 +256,7 @@
 ; CHECK:       // %bb.0:
 ; CHECK-NEXT:    subs x0, x0, x4
 ; CHECK-NEXT:    sbcs x1, x1, x5
-; CHECK-NEXT:    cset w8, lo
-; CHECK-NEXT:    cmp wzr, w8
 ; CHECK-NEXT:    sbcs x2, x2, x6
-; CHECK-NEXT:    cset w8, lo
-; CHECK-NEXT:    cmp wzr, w8
 ; CHECK-NEXT:    sbcs x3, x3, x7
 ; CHECK-NEXT:    cset w4, vs
 ; CHECK-NEXT:    ret
diff --git a/llvm/test/CodeGen/M68k/Control/cmp.ll b/llvm/test/CodeGen/M68k/Control/cmp.ll
--- a/llvm/test/CodeGen/M68k/Control/cmp.ll
+++ b/llvm/test/CodeGen/M68k/Control/cmp.ll
@@ -103,7 +103,6 @@
 ; CHECK-NEXT:    subx.l %d0, %d1
 ; CHECK-NEXT:    slt %d1
 ; CHECK-NEXT:    and.l #255, %d1
-; CHECK-NEXT:    and.l #1, %d1
 ; CHECK-NEXT:    movem.l (0,%sp), %d2 ; 8-byte Folded Reload
 ; CHECK-NEXT:    adda.l #4, %sp
 ; CHECK-NEXT:    rts
diff --git a/llvm/test/CodeGen/M68k/Control/setcc.ll b/llvm/test/CodeGen/M68k/Control/setcc.ll
--- a/llvm/test/CodeGen/M68k/Control/setcc.ll
+++ b/llvm/test/CodeGen/M68k/Control/setcc.ll
@@ -46,7 +46,6 @@
 ; CHECK-NEXT:    scs %d0
 ; CHECK-NEXT:    move.l %d0, %d1
 ; CHECK-NEXT:    and.l #255, %d1
-; CHECK-NEXT:    and.l #1, %d1
 ; CHECK-NEXT:    lsl.l #6, %d1
 ; CHECK-NEXT:    move.l %d2, %d0
 ; CHECK-NEXT:    movem.l (0,%sp), %d2 ; 8-byte Folded Reload