[SandboxIR] Implement PossiblyNonNegInst (#106149)

This patch implements sandboxir::PossiblyNonNegInst mirroring
llvm::PossiblyNonNegInst.

Author: vporpo

llvm/include/llvm/SandboxIR/SandboxIR.h

@@ -137,6 +137,7 @@ class CatchReturnInst;
 class CleanupReturnInst;
 class GetElementPtrInst;
 class CastInst;
+class PossiblyNonNegInst;
 class PtrToIntInst;
 class BitCastInst;
 class AllocaInst;
@@ -2762,6 +2763,28 @@ class CastInst : public UnaryInstruction {
   Type *getDestTy() const { return cast<llvm::CastInst>(Val)->getDestTy(); }
 };
 
+/// Instruction that can have a nneg flag (zext/uitofp).
+class PossiblyNonNegInst : public CastInst {
+public:
+  bool hasNonNeg() const {
+    return cast<llvm::PossiblyNonNegInst>(Val)->hasNonNeg();
+  }
+  void setNonNeg(bool B);
+  /// For isa/dyn_cast.
+  static bool classof(const Value *From) {
+    if (auto *I = dyn_cast<Instruction>(From)) {
+      switch (I->getOpcode()) {
+      case Opcode::ZExt:
+      case Opcode::UIToFP:
+        return true;
+      default:
+        return false;
+      }
+    }
+    return false;
+  }
+};
+
 // Helper class to simplify stamping out CastInst subclasses.
 template <Instruction::Opcode Op> class CastInstImpl : public CastInst {
 public:

llvm/lib/SandboxIR/SandboxIR.cpp

@@ -1991,6 +1991,13 @@ bool CastInst::classof(const Value *From) {
   return From->getSubclassID() == ClassID::Cast;
 }
 
+void PossiblyNonNegInst::setNonNeg(bool B) {
+  Ctx.getTracker()
+      .emplaceIfTracking<GenericSetter<&PossiblyNonNegInst::hasNonNeg,
+                                       &PossiblyNonNegInst::setNonNeg>>(this);
+  cast<llvm::PossiblyNonNegInst>(Val)->setNonNeg(B);
+}
+
 Value *InsertElementInst::create(Value *Vec, Value *NewElt, Value *Idx,
                                  Instruction *InsertBefore, Context &Ctx,
                                  const Twine &Name) {

llvm/unittests/SandboxIR/SandboxIRTest.cpp

@@ -3682,6 +3682,48 @@ define void @foo(i32 %arg, float %farg, double %darg, ptr %ptr) {
   }
 }
 
+TEST_F(SandboxIRTest, PossiblyNonNegInst) {
+  parseIR(C, R"IR(
+define void @foo(i32 %arg, float %farg, double %darg, ptr %ptr) {
+  %zext = zext i32 %arg to i64
+  %uitofp = uitofp i32 %arg to float
+
+  %sext = sext i32 %arg to i64
+  %fptoui = fptoui float %farg to i32
+  %fptosi = fptosi float %farg to i32
+  %fpext = fpext float %farg to double
+  %ptrtoint = ptrtoint ptr %ptr to i32
+  %inttoptr = inttoptr i32 %arg to ptr
+  %sitofp = sitofp i32 %arg to float
+  %trunc = trunc i32 %arg to i16
+  %fptrunc = fptrunc double %darg to float
+  %bitcast = bitcast i32 %arg to float
+  %addrspacecast = addrspacecast ptr %ptr to ptr addrspace(1)
+  ret void
+}
+)IR");
+  Function &LLVMF = *M->getFunction("foo");
+  sandboxir::Context Ctx(C);
+  sandboxir::Function *F = Ctx.createFunction(&LLVMF);
+  auto *BB = &*F->begin();
+  auto It = BB->begin();
+  auto *PNNI0 = cast<sandboxir::PossiblyNonNegInst>(&*It++);
+  auto *PNNI1 = cast<sandboxir::PossiblyNonNegInst>(&*It++);
+  for (auto ItE = BB->end(); It != ItE; ++It)
+    EXPECT_FALSE(isa<sandboxir::PossiblyNonNegInst>(&*It++));
+
+  for (auto *PNNI : {PNNI0, PNNI1}) {
+    // Check setNonNeg(), hasNonNeg().
+    auto OrigNonNeg = PNNI->hasNonNeg();
+    auto NewNonNeg = true;
+    EXPECT_NE(NewNonNeg, OrigNonNeg);
+    PNNI->setNonNeg(NewNonNeg);
+    EXPECT_EQ(PNNI->hasNonNeg(), NewNonNeg);
+    PNNI->setNonNeg(OrigNonNeg);
+    EXPECT_EQ(PNNI->hasNonNeg(), OrigNonNeg);
+  }
+}
+
 /// CastInst's subclasses are very similar so we can use a common test function
 /// for them.
 template <typename SubclassT, sandboxir::Instruction::Opcode OpcodeT>

llvm/unittests/SandboxIR/TrackerTest.cpp

@@ -1014,6 +1014,32 @@ define void @foo(i8 %arg0, i8 %arg1) {
   EXPECT_EQ(PDI->isDisjoint(), OrigIsDisjoint);
 }
 
+TEST_F(TrackerTest, PossiblyNonNegInstSetters) {
+  parseIR(C, R"IR(
+define void @foo(i32 %arg) {
+  %zext = zext i32 %arg to i64
+  ret void
+}
+)IR");
+  Function &LLVMF = *M->getFunction("foo");
+  sandboxir::Context Ctx(C);
+
+  auto &F = *Ctx.createFunction(&LLVMF);
+  auto *BB = &*F.begin();
+  auto It = BB->begin();
+  auto *PNNI = cast<sandboxir::PossiblyNonNegInst>(&*It++);
+
+  // Check setNonNeg().
+  auto OrigNonNeg = PNNI->hasNonNeg();
+  auto NewNonNeg = true;
+  EXPECT_NE(NewNonNeg, OrigNonNeg);
+  Ctx.save();
+  PNNI->setNonNeg(NewNonNeg);
+  EXPECT_EQ(PNNI->hasNonNeg(), NewNonNeg);
+  Ctx.revert();
+  EXPECT_EQ(PNNI->hasNonNeg(), OrigNonNeg);
+}
+
 TEST_F(TrackerTest, AtomicRMWSetters) {
   parseIR(C, R"IR(
 define void @foo(ptr %ptr, i8 %arg) {