[llvm] [LLVM][SelectionDAG] Align poison/undef binop folds with IR. (PR #149334)

[Matt Arsenault via llvm-commits]

================
@@ -0,0 +1,335 @@
+//===---- llvm/unittest/CodeGen/SelectionDAGPatternMatchTest.cpp ----------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "SelectionDAGTestBase.h"
+
+using namespace llvm;
+
+class SelectionDAGNodeConstructionTest : public SelectionDAGTestBase {};
+
+TEST_F(SelectionDAGNodeConstructionTest, ADD) {
+  SDLoc DL;
+  EVT Int32VT = EVT::getIntegerVT(Context, 32);
+  SDValue Poison = DAG->getPOISON(Int32VT);
+  SDValue Undef = DAG->getUNDEF(Int32VT);
+  SDValue Op = DAG->getCopyFromReg(DAG->getEntryNode(), DL, 1, Int32VT);
+
+  EXPECT_EQ(DAG->getNode(ISD::ADD, DL, Int32VT, Op, Poison), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::ADD, DL, Int32VT, Poison, Op), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::ADD, DL, Int32VT, Poison, Undef), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::ADD, DL, Int32VT, Undef, Poison), Poison);
+
+  EXPECT_EQ(DAG->getNode(ISD::ADD, DL, Int32VT, Op, Undef), Undef);
+  EXPECT_EQ(DAG->getNode(ISD::ADD, DL, Int32VT, Undef, Op), Undef);
+  EXPECT_EQ(DAG->getNode(ISD::ADD, DL, Int32VT, Undef, Undef), Undef);
+}
+
+TEST_F(SelectionDAGNodeConstructionTest, AND) {
+  SDLoc DL;
+  EVT Int32VT = EVT::getIntegerVT(Context, 32);
+  SDValue Op = DAG->getCopyFromReg(DAG->getEntryNode(), DL, 1, Int32VT);
+  SDValue Poison = DAG->getPOISON(Int32VT);
+  SDValue Undef = DAG->getUNDEF(Int32VT);
+  SDValue Zero = DAG->getConstant(0, DL, Int32VT);
+
+  EXPECT_EQ(DAG->getNode(ISD::AND, DL, Int32VT, Op, Poison), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::AND, DL, Int32VT, Poison, Op), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::AND, DL, Int32VT, Poison, Undef), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::AND, DL, Int32VT, Undef, Poison), Poison);
+
+  EXPECT_EQ(DAG->getNode(ISD::AND, DL, Int32VT, Op, Undef), Zero);
+  EXPECT_EQ(DAG->getNode(ISD::AND, DL, Int32VT, Undef, Op), Zero);
+  EXPECT_EQ(DAG->getNode(ISD::AND, DL, Int32VT, Undef, Undef), Undef);
+}
+
+TEST_F(SelectionDAGNodeConstructionTest, MUL) {
+  SDLoc DL;
+  EVT Int32VT = EVT::getIntegerVT(Context, 32);
+  SDValue Op = DAG->getCopyFromReg(DAG->getEntryNode(), DL, 1, Int32VT);
+  SDValue Poison = DAG->getPOISON(Int32VT);
+  SDValue Undef = DAG->getUNDEF(Int32VT);
+  SDValue Zero = DAG->getConstant(0, DL, Int32VT);
+
+  EXPECT_EQ(DAG->getNode(ISD::MUL, DL, Int32VT, Op, Poison), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::MUL, DL, Int32VT, Poison, Op), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::MUL, DL, Int32VT, Poison, Undef), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::MUL, DL, Int32VT, Undef, Poison), Poison);
+
+  EXPECT_EQ(DAG->getNode(ISD::MUL, DL, Int32VT, Op, Undef), Zero);
+  EXPECT_EQ(DAG->getNode(ISD::MUL, DL, Int32VT, Undef, Op), Zero);
+  EXPECT_EQ(DAG->getNode(ISD::MUL, DL, Int32VT, Undef, Undef), Undef);
+}
+
+TEST_F(SelectionDAGNodeConstructionTest, OR) {
+  SDLoc DL;
+  EVT Int32VT = EVT::getIntegerVT(Context, 32);
+  SDValue Op = DAG->getCopyFromReg(DAG->getEntryNode(), DL, 1, Int32VT);
+  SDValue Poison = DAG->getPOISON(Int32VT);
+  SDValue Undef = DAG->getUNDEF(Int32VT);
+  SDValue AllOnes = DAG->getAllOnesConstant(DL, Int32VT);
+
+  EXPECT_EQ(DAG->getNode(ISD::OR, DL, Int32VT, Op, Poison), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::OR, DL, Int32VT, Poison, Op), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::OR, DL, Int32VT, Poison, Undef), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::OR, DL, Int32VT, Undef, Poison), Poison);
+
+  EXPECT_EQ(DAG->getNode(ISD::OR, DL, Int32VT, Op, Undef), AllOnes);
+  EXPECT_EQ(DAG->getNode(ISD::OR, DL, Int32VT, Undef, Op), AllOnes);
+  EXPECT_EQ(DAG->getNode(ISD::OR, DL, Int32VT, Undef, Undef), Undef);
+}
+
+TEST_F(SelectionDAGNodeConstructionTest, SADDSAT) {
+  SDLoc DL;
+  EVT Int32VT = EVT::getIntegerVT(Context, 32);
+  SDValue Op = DAG->getCopyFromReg(DAG->getEntryNode(), DL, 1, Int32VT);
+  SDValue Poison = DAG->getPOISON(Int32VT);
+  SDValue Undef = DAG->getUNDEF(Int32VT);
+  SDValue AllOnes = DAG->getAllOnesConstant(DL, Int32VT);
+
+  EXPECT_EQ(DAG->getNode(ISD::SADDSAT, DL, Int32VT, Op, Poison), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::SADDSAT, DL, Int32VT, Poison, Op), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::SADDSAT, DL, Int32VT, Poison, Undef), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::SADDSAT, DL, Int32VT, Undef, Poison), Poison);
+
+  EXPECT_EQ(DAG->getNode(ISD::SADDSAT, DL, Int32VT, Op, Undef), AllOnes);
+  EXPECT_EQ(DAG->getNode(ISD::SADDSAT, DL, Int32VT, Undef, Op), AllOnes);
+  EXPECT_EQ(DAG->getNode(ISD::SADDSAT, DL, Int32VT, Undef, Undef), Undef);
+}
+
+TEST_F(SelectionDAGNodeConstructionTest, SDIV) {
+  SDLoc DL;
+  EVT Int32VT = EVT::getIntegerVT(Context, 32);
+  SDValue Op = DAG->getCopyFromReg(DAG->getEntryNode(), DL, 1, Int32VT);
+  SDValue Poison = DAG->getPOISON(Int32VT);
+  SDValue Undef = DAG->getUNDEF(Int32VT);
+  SDValue Zero = DAG->getConstant(0, DL, Int32VT);
+
+  EXPECT_EQ(DAG->getNode(ISD::SDIV, DL, Int32VT, Op, Poison), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::SDIV, DL, Int32VT, Poison, Op), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::SDIV, DL, Int32VT, Poison, Undef), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::SDIV, DL, Int32VT, Undef, Poison), Poison);
+
+  EXPECT_EQ(DAG->getNode(ISD::SDIV, DL, Int32VT, Op, Undef), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::SDIV, DL, Int32VT, Undef, Op), Zero);
+  EXPECT_EQ(DAG->getNode(ISD::SDIV, DL, Int32VT, Undef, Undef), Poison);
+}
+
+TEST_F(SelectionDAGNodeConstructionTest, SMAX) {
+  SDLoc DL;
+  auto Int32VT = EVT::getIntegerVT(Context, 32);
+  SDValue Op = DAG->getCopyFromReg(DAG->getEntryNode(), DL, 1, Int32VT);
+  SDValue Poison = DAG->getPOISON(Int32VT);
+  SDValue Undef = DAG->getUNDEF(Int32VT);
+  SDValue MaxInt = DAG->getConstant(APInt::getSignedMaxValue(32), DL, Int32VT);
+
+  EXPECT_EQ(DAG->getNode(ISD::SMAX, DL, Int32VT, Op, Poison), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::SMAX, DL, Int32VT, Poison, Op), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::SMAX, DL, Int32VT, Poison, Undef), Poison);
+  EXPECT_EQ(DAG->getNode(ISD::SMAX, DL, Int32VT, Undef, Poison), Poison);
+
+  EXPECT_EQ(DAG->getNode(ISD::SMAX, DL, Int32VT, Op, Undef), MaxInt);
+  EXPECT_EQ(DAG->getNode(ISD::SMAX, DL, Int32VT, Undef, Op), MaxInt);
+  EXPECT_EQ(DAG->getNode(ISD::SMAX, DL, Int32VT, Undef, Undef), Undef);
+}
+
+TEST_F(SelectionDAGNodeConstructionTest, SMIN) {
+  SDLoc DL;
+  auto Int32VT = EVT::getIntegerVT(Context, 32);
----------------
arsenm wrote:

Just use MVT::i32 directly, same throughout 

https://github.com/llvm/llvm-project/pull/149334