[InstCombine] Extend sext/zext boolean additions to vectors

Reported-by: shao-hua-li

Fixes: #68745.

Author: antoniofrighetto

llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp

@@ -2899,9 +2899,17 @@ Instruction *InstCombinerImpl::foldICmpSubConstant(ICmpInst &Cmp,
 static Value *createLogicFromTable(const std::bitset<4> &Table, Value *Op0,
                                    Value *Op1, IRBuilderBase &Builder,
                                    bool HasOneUse) {
+  auto FoldConstant = [&](bool Val) {
+    Constant *Res = Val ? Builder.getTrue() : Builder.getFalse();
+    if (Op0->getType()->isVectorTy())
+      Res = ConstantVector::getSplat(
+          cast<VectorType>(Op0->getType())->getElementCount(), Res);
+    return Res;
+  };
+
   switch (Table.to_ulong()) {
   case 0: // 0 0 0 0
-    return Builder.getFalse();
+    return FoldConstant(false);
   case 1: // 0 0 0 1
     return HasOneUse ? Builder.CreateNot(Builder.CreateOr(Op0, Op1)) : nullptr;
   case 2: // 0 0 1 0
@@ -2931,7 +2939,7 @@ static Value *createLogicFromTable(const std::bitset<4> &Table, Value *Op0,
   case 14: // 1 1 1 0
     return Builder.CreateOr(Op0, Op1);
   case 15: // 1 1 1 1
-    return Builder.getTrue();
+    return FoldConstant(true);
   default:
     llvm_unreachable("Invalid Operation");
   }

llvm/test/Transforms/InstCombine/icmp-add.ll

@@ -515,6 +515,19 @@ bb:
   ret i1 %t
 }
 
+define <2 x i1> @cvt_icmp_2_sext_plus_zext_ne_vec(<2 x i1> %arg, <2 x i1> %arg1) {
+; CHECK-LABEL: @cvt_icmp_2_sext_plus_zext_ne_vec(
+; CHECK-NEXT:  bb:
+; CHECK-NEXT:    ret <2 x i1> <i1 true, i1 true>
+;
+bb:
+  %i = sext <2 x i1> %arg to <2 x i32>
+  %i2 = zext <2 x i1> %arg1 to <2 x i32>
+  %i3 = add nsw <2 x i32> %i, %i2
+  %i4 = icmp ne <2 x i32> %i3, <i32 2, i32 2>
+  ret <2 x i1> %i4
+}
+
 ; test if zext i1 X + sext i1 Y converted to sext i1 X + zext i1 Y
 ; and then processed
 
@@ -531,6 +544,19 @@ bb:
   ret i1 %t
 }
 
+define <2 x i1> @cvt_icmp_neg_2_zext_plus_sext_eq_vec(<2 x i1> %arg, <2 x i1> %arg1) {
+; CHECK-LABEL: @cvt_icmp_neg_2_zext_plus_sext_eq_vec(
+; CHECK-NEXT:  bb:
+; CHECK-NEXT:    ret <2 x i1> zeroinitializer
+;
+bb:
+  %i = zext <2 x i1> %arg to <2 x i32>
+  %i2 = sext <2 x i1> %arg1 to <2 x i32>
+  %i3 = add nsw <2 x i32> %i2, %i
+  %i4 = icmp eq <2 x i32> %i3, <i32 2, i32 2>
+  ret <2 x i1> %i4
+}
+
 define i1 @cvt_icmp_neg_1_zext_plus_sext_eq(i1 %arg, i1 %arg1) {
 ; CHECK-LABEL: @cvt_icmp_neg_1_zext_plus_sext_eq(
 ; CHECK-NEXT:  bb: