[InstCombine] reduce code duplication in SimplifyDemandedVectorElts; NFCI

llvm-svn: 343806

1 files changed, 42 insertions, 91 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
index 1b5e28ff17f..f8b57eeb388 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
@@ -1052,8 +1052,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
 
   UndefElts = 0;
 
-  // Handle ConstantAggregateZero, ConstantVector, ConstantDataSequential.
-  if (Constant *C = dyn_cast<Constant>(V)) {
+  if (auto *C = dyn_cast<Constant>(V)) {
     // Check if this is identity. If so, return 0 since we are not simplifying
     // anything.
     if (DemandedElts.isAllOnesValue())
@@ -1061,7 +1060,6 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
 
     Type *EltTy = cast<VectorType>(V->getType())->getElementType();
     Constant *Undef = UndefValue::get(EltTy);
-
     SmallVector<Constant*, 16> Elts;
     for (unsigned i = 0; i != VWidth; ++i) {
       if (!DemandedElts[i]) {   // If not demanded, set to undef.
@@ -1109,9 +1107,21 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
   if (!I) return nullptr;        // Only analyze instructions.
 
   bool MadeChange = false;
+  auto simplifyAndSetOp = [&](Instruction *Inst, unsigned OpNum,
+                              APInt Demanded, APInt &Undef) {
+    auto *II = dyn_cast<IntrinsicInst>(Inst);
+    Value *Op = II ? II->getArgOperand(OpNum) : Inst->getOperand(OpNum);
+    if (Value *V = SimplifyDemandedVectorElts(Op, Demanded, Undef, Depth + 1)) {
+      if (II)
+        II->setArgOperand(OpNum, V);
+      else
+        Inst->setOperand(OpNum, V);
+      MadeChange = true;
+    }
+  };
+
   APInt UndefElts2(VWidth, 0);
   APInt UndefElts3(VWidth, 0);
-  Value *TmpV;
   switch (I->getOpcode()) {
   default: break;
 
@@ -1122,9 +1132,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
     if (!Idx) {
       // Note that we can't propagate undef elt info, because we don't know
       // which elt is getting updated.
-      TmpV = SimplifyDemandedVectorElts(I->getOperand(0), DemandedElts,
-                                        UndefElts2, Depth + 1);
-      if (TmpV) { I->setOperand(0, TmpV); MadeChange = true; }
+      simplifyAndSetOp(I, 0, DemandedElts, UndefElts2);
       break;
     }
 
@@ -1134,9 +1142,8 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
     APInt PreInsertDemandedElts = DemandedElts;
     if (IdxNo < VWidth)
       PreInsertDemandedElts.clearBit(IdxNo);
-    TmpV = SimplifyDemandedVectorElts(I->getOperand(0), PreInsertDemandedElts,
-                                      UndefElts, Depth + 1);
-    if (TmpV) { I->setOperand(0, TmpV); MadeChange = true; }
+
+    simplifyAndSetOp(I, 0, PreInsertDemandedElts, UndefElts);
 
     // If this is inserting an element that isn't demanded, remove this
     // insertelement.
@@ -1169,14 +1176,10 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
     }
 
     APInt LHSUndefElts(LHSVWidth, 0);
-    TmpV = SimplifyDemandedVectorElts(I->getOperand(0), LeftDemanded,
-                                      LHSUndefElts, Depth + 1);
-    if (TmpV) { I->setOperand(0, TmpV); MadeChange = true; }
+    simplifyAndSetOp(I, 0, LeftDemanded, LHSUndefElts);
 
     APInt RHSUndefElts(LHSVWidth, 0);
-    TmpV = SimplifyDemandedVectorElts(I->getOperand(1), RightDemanded,
-                                      RHSUndefElts, Depth + 1);
-    if (TmpV) { I->setOperand(1, TmpV); MadeChange = true; }
+    simplifyAndSetOp(I, 1, RightDemanded, RHSUndefElts);
 
     bool NewUndefElts = false;
     unsigned LHSIdx = -1u, LHSValIdx = -1u;
@@ -1269,12 +1272,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
       // element of the select condition is known undef, then we are free to
       // choose the output value from either arm of the select. If we know that
       // one of those values is undef, then the output can be undef.
-      if (Value *V = SimplifyDemandedVectorElts(Sel->getCondition(),
-                                                DemandedElts, UndefElts,
-                                                Depth + 1)) {
-        Sel->setCondition(V);
-        MadeChange = true;
-      }
+      simplifyAndSetOp(I, 0, DemandedElts, UndefElts);
     }
 
     // Next, see if we can transform the arms of the select.
@@ -1296,17 +1294,8 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
       }
     }
 
-    if (Value *V = SimplifyDemandedVectorElts(Sel->getTrueValue(), DemandedLHS,
-                                              UndefElts2, Depth + 1)) {
-      Sel->setTrueValue(V);
-      MadeChange = true;
-    }
-
-    if (Value *V = SimplifyDemandedVectorElts(Sel->getFalseValue(), DemandedRHS,
-                                              UndefElts3, Depth + 1)) {
-      Sel->setFalseValue(V);
-      MadeChange = true;
-    }
+    simplifyAndSetOp(I, 1, DemandedLHS, UndefElts2);
+    simplifyAndSetOp(I, 2, DemandedRHS, UndefElts3);
 
     // Output elements are undefined if the element from each arm is undefined.
     // TODO: This can be improved. See comment in select condition handling.
@@ -1348,12 +1337,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
       break;
     }
 
-    TmpV = SimplifyDemandedVectorElts(I->getOperand(0), InputDemandedElts,
-                                      UndefElts2, Depth + 1);
-    if (TmpV) {
-      I->setOperand(0, TmpV);
-      MadeChange = true;
-    }
+    simplifyAndSetOp(I, 0, InputDemandedElts, UndefElts2);
 
     if (VWidth == InVWidth) {
       UndefElts = UndefElts2;
@@ -1380,9 +1364,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
   }
   case Instruction::FPTrunc:
   case Instruction::FPExt:
-    TmpV = SimplifyDemandedVectorElts(I->getOperand(0), DemandedElts, UndefElts,
-                                      Depth + 1);
-    if (TmpV) { I->setOperand(0, TmpV); MadeChange = true; }
+    simplifyAndSetOp(I, 0, DemandedElts, UndefElts);
     break;
 
   case Instruction::Call: {
@@ -1402,9 +1384,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
 
       // Only the lower element is used.
       DemandedElts = 1;
-      TmpV = SimplifyDemandedVectorElts(II->getArgOperand(0), DemandedElts,
-                                        UndefElts, Depth + 1);
-      if (TmpV) { II->setArgOperand(0, TmpV); MadeChange = true; }
+      simplifyAndSetOp(II, 0, DemandedElts, UndefElts);
 
       // Only the lower element is undefined. The high elements are zero.
       UndefElts = UndefElts[0];
@@ -1413,9 +1393,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
     // Unary scalar-as-vector operations that work column-wise.
     case Intrinsic::x86_sse_rcp_ss:
     case Intrinsic::x86_sse_rsqrt_ss:
-      TmpV = SimplifyDemandedVectorElts(II->getArgOperand(0), DemandedElts,
-                                        UndefElts, Depth + 1);
-      if (TmpV) { II->setArgOperand(0, TmpV); MadeChange = true; }
+      simplifyAndSetOp(II, 0, DemandedElts, UndefElts);
 
       // If lowest element of a scalar op isn't used then use Arg0.
       if (!DemandedElts[0]) {
@@ -1435,9 +1413,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
     case Intrinsic::x86_sse2_min_sd:
     case Intrinsic::x86_sse2_max_sd:
     case Intrinsic::x86_sse2_cmp_sd: {
-      TmpV = SimplifyDemandedVectorElts(II->getArgOperand(0), DemandedElts,
-                                        UndefElts, Depth + 1);
-      if (TmpV) { II->setArgOperand(0, TmpV); MadeChange = true; }
+      simplifyAndSetOp(II, 0, DemandedElts, UndefElts);
 
       // If lowest element of a scalar op isn't used then use Arg0.
       if (!DemandedElts[0]) {
@@ -1447,9 +1423,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
 
       // Only lower element is used for operand 1.
       DemandedElts = 1;
-      TmpV = SimplifyDemandedVectorElts(II->getArgOperand(1), DemandedElts,
-                                        UndefElts2, Depth + 1);
-      if (TmpV) { II->setArgOperand(1, TmpV); MadeChange = true; }
+      simplifyAndSetOp(II, 1, DemandedElts, UndefElts2);
 
       // Lower element is undefined if both lower elements are undefined.
       // Consider things like undef&0.  The result is known zero, not undef.
@@ -1466,9 +1440,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
       // Don't use the low element of operand 0.
       APInt DemandedElts2 = DemandedElts;
       DemandedElts2.clearBit(0);
-      TmpV = SimplifyDemandedVectorElts(II->getArgOperand(0), DemandedElts2,
-                                        UndefElts, Depth + 1);
-      if (TmpV) { II->setArgOperand(0, TmpV); MadeChange = true; }
+      simplifyAndSetOp(II, 0, DemandedElts2, UndefElts);
 
       // If lowest element of a scalar op isn't used then use Arg0.
       if (!DemandedElts[0]) {
@@ -1478,9 +1450,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
 
       // Only lower element is used for operand 1.
       DemandedElts = 1;
-      TmpV = SimplifyDemandedVectorElts(II->getArgOperand(1), DemandedElts,
-                                        UndefElts2, Depth + 1);
-      if (TmpV) { II->setArgOperand(1, TmpV); MadeChange = true; }
+      simplifyAndSetOp(II, 1, DemandedElts, UndefElts2);
 
       // Take the high undef elements from operand 0 and take the lower element
       // from operand 1.
@@ -1504,9 +1474,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
     case Intrinsic::x86_avx512_mask_sub_sd_round:
     case Intrinsic::x86_avx512_mask_max_sd_round:
     case Intrinsic::x86_avx512_mask_min_sd_round:
-      TmpV = SimplifyDemandedVectorElts(II->getArgOperand(0), DemandedElts,
-                                        UndefElts, Depth + 1);
-      if (TmpV) { II->setArgOperand(0, TmpV); MadeChange = true; }
+      simplifyAndSetOp(II, 0, DemandedElts, UndefElts);
 
       // If lowest element of a scalar op isn't used then use Arg0.
       if (!DemandedElts[0]) {
@@ -1516,12 +1484,8 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
 
       // Only lower element is used for operand 1 and 2.
       DemandedElts = 1;
-      TmpV = SimplifyDemandedVectorElts(II->getArgOperand(1), DemandedElts,
-                                        UndefElts2, Depth + 1);
-      if (TmpV) { II->setArgOperand(1, TmpV); MadeChange = true; }
-      TmpV = SimplifyDemandedVectorElts(II->getArgOperand(2), DemandedElts,
-                                        UndefElts3, Depth + 1);
-      if (TmpV) { II->setArgOperand(2, TmpV); MadeChange = true; }
+      simplifyAndSetOp(II, 1, DemandedElts, UndefElts2);
+      simplifyAndSetOp(II, 2, DemandedElts, UndefElts3);
 
       // Lower element is undefined if all three lower elements are undefined.
       // Consider things like undef&0.  The result is known zero, not undef.
@@ -1566,14 +1530,8 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
         }
 
         // Demand elements from the operand.
-        auto *Op = II->getArgOperand(OpNum);
         APInt OpUndefElts(InnerVWidth, 0);
-        TmpV = SimplifyDemandedVectorElts(Op, OpDemandedElts, OpUndefElts,
-                                          Depth + 1);
-        if (TmpV) {
-          II->setArgOperand(OpNum, TmpV);
-          MadeChange = true;
-        }
+        simplifyAndSetOp(II, OpNum, OpDemandedElts, OpUndefElts);
 
         // Pack the operand's UNDEF elements, one lane at a time.
         OpUndefElts = OpUndefElts.zext(VWidth);
@@ -1601,10 +1559,7 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
     // PERMV
     case Intrinsic::x86_avx2_permd:
     case Intrinsic::x86_avx2_permps: {
-      Value *Op1 = II->getArgOperand(1);
-      TmpV = SimplifyDemandedVectorElts(Op1, DemandedElts, UndefElts,
-                                        Depth + 1);
-      if (TmpV) { II->setArgOperand(1, TmpV); MadeChange = true; }
+      simplifyAndSetOp(II, 1, DemandedElts, UndefElts);
       break;
     }
 
@@ -1625,27 +1580,23 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
 
       break;
     }
-    }
+    } // switch on IntrinsicID
     break;
-  }
-  }
+  } // case Call
+  } // switch on Opcode
 
   // TODO: We bail completely on integer div/rem and shifts because they have
   // UB/poison potential, but that should be refined.
   BinaryOperator *BO;
   if (match(I, m_BinOp(BO)) && !BO->isIntDivRem() && !BO->isShift()) {
-    TmpV = SimplifyDemandedVectorElts(I->getOperand(0), DemandedElts, UndefElts,
-                                      Depth + 1);
-    if (TmpV) { I->setOperand(0, TmpV); MadeChange = true; }
-    TmpV = SimplifyDemandedVectorElts(I->getOperand(1), DemandedElts,
-                                      UndefElts2, Depth + 1);
-    if (TmpV) { I->setOperand(1, TmpV); MadeChange = true; }
+    simplifyAndSetOp(I, 0, DemandedElts, UndefElts);
+    simplifyAndSetOp(I, 1, DemandedElts, UndefElts2);
 
     // TODO: If this is a potentially poison-producing instruction, we need
     // to drop the wrapping/exact flags?
 
-    // Output elements are undefined if both are undefined.  Consider things
-    // like undef&0.  The result is known zero, not undef.
+    // Output elements are undefined if both are undefined. Consider things
+    // like undef & 0. The result is known zero, not undef.
     UndefElts &= UndefElts2;
   }