[InstCombine][NFC] Add tests with icmp splat vectors and B masks

Add tests to verifying future support for splat vectors containing poison/undef in llvm::decomposeBitTestICmp.

Differential Revision: https://reviews.llvm.org/D143031

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

@@ -377,6 +377,36 @@ define i1 @fold_mask_cmps_to_true_logical(i32 %x) {
   ret i1 %t4
 }
 
+define <2 x i1> @nomask_splat_and_B_allones(<2 x i32> %A) {
+; CHECK-LABEL: @nomask_splat_and_B_allones(
+; CHECK-NEXT:    [[TST1:%.*]] = icmp slt <2 x i32> [[A:%.*]], <i32 0, i32 poison>
+; CHECK-NEXT:    [[MASK2:%.*]] = and <2 x i32> [[A]], <i32 1879048192, i32 1879048192>
+; CHECK-NEXT:    [[TST2:%.*]] = icmp eq <2 x i32> [[MASK2]], <i32 1879048192, i32 1879048192>
+; CHECK-NEXT:    [[RES:%.*]] = and <2 x i1> [[TST1]], [[TST2]]
+; CHECK-NEXT:    ret <2 x i1> [[RES]]
+;
+  %tst1 = icmp slt <2 x i32> %A, <i32 0, i32 poison>
+  %mask2 = and <2 x i32> %A, <i32 1879048192, i32 1879048192>
+  %tst2 = icmp eq <2 x i32> %mask2, <i32 1879048192, i32 1879048192>
+  %res = and <2 x i1> %tst1, %tst2
+  ret <2 x i1> %res
+}
+
+define <2 x i1> @nomask_splat_and_B_mixed(<2 x i32> %A) {
+; CHECK-LABEL: @nomask_splat_and_B_mixed(
+; CHECK-NEXT:    [[TST1:%.*]] = icmp sgt <2 x i32> [[A:%.*]], <i32 -1, i32 poison>
+; CHECK-NEXT:    [[MASK2:%.*]] = and <2 x i32> [[A]], <i32 1879048192, i32 1879048192>
+; CHECK-NEXT:    [[TST2:%.*]] = icmp eq <2 x i32> [[MASK2]], <i32 1879048192, i32 1879048192>
+; CHECK-NEXT:    [[RES:%.*]] = and <2 x i1> [[TST1]], [[TST2]]
+; CHECK-NEXT:    ret <2 x i1> [[RES]]
+;
+  %tst1 = icmp sgt <2 x i32> %A, <i32 -1, i32 poison>
+  %mask2 = and <2 x i32> %A, <i32 1879048192, i32 1879048192>
+  %tst2 = icmp eq <2 x i32> %mask2, <i32 1879048192, i32 1879048192>
+  %res = and <2 x i1> %tst1, %tst2
+  ret <2 x i1> %res
+}
+
 ; PR32401 - https://bugs.llvm.org/show_bug.cgi?id=32401
 
 define i1 @cmpeq_bitwise(i8 %a, i8 %b, i8 %c, i8 %d) {