[llvm] [SandboxIR] Add callbacks for instruction insert/remove/move ops (PR #112965)

[Sriraman Tallam via llvm-commits]

================
@@ -5962,3 +5963,87 @@ TEST_F(SandboxIRTest, CheckClassof) {
   EXPECT_NE(&sandboxir::CLASS::classof, &sandboxir::Instruction::classof);
 #include "llvm/SandboxIR/Values.def"
 }
+
+TEST_F(SandboxIRTest, InstructionCallbacks) {
+  parseIR(C, R"IR(
+    define void @foo(ptr %ptr, i8 %val) {
+      ret void
+    }
+  )IR");
+  Function &LLVMF = *M->getFunction("foo");
+  sandboxir::Context Ctx(C);
+
+  auto &F = *Ctx.createFunction(&LLVMF);
+  auto &BB = *F.begin();
+  sandboxir::Argument *Ptr = F.getArg(0);
+  sandboxir::Argument *Val = F.getArg(1);
+  sandboxir::Instruction *Ret = &BB.front();
+
+  SmallVector<sandboxir::Instruction *> Inserted;
+  auto InsertCbId = Ctx.registerInsertInstrCallback(
+      [&Inserted](sandboxir::Instruction *I) { Inserted.push_back(I); });
+
+  SmallVector<sandboxir::Instruction *> Removed;
+  auto RemoveCbId = Ctx.registerRemoveInstrCallback(
+      [&Removed](sandboxir::Instruction *I) { Removed.push_back(I); });
+
+  // Keep the moved instruction and the instruction pointed by the Where
+  // iterator so we can check both callback arguments work as expected.
+  SmallVector<std::pair<sandboxir::Instruction *, sandboxir::Instruction *>>
+      Moved;
+  auto MoveCbId = Ctx.registerMoveInstrCallback(
+      [&Moved](sandboxir::Instruction *I, const sandboxir::BBIterator &Where) {
+        // Use a nullptr to signal "move to end" to keep it single. We only
+        // have a basic block in this test case anyway.
+        if (Where == Where.getNodeParent()->end())
+          Moved.push_back(std::make_pair(I, nullptr));
+        else
+          Moved.push_back(std::make_pair(I, &*Where));
+      });
+
+  Ctx.save();
+  auto *NewI = sandboxir::StoreInst::create(Val, Ptr, /*Align=*/std::nullopt,
+                                            Ret->getIterator(), Ctx);
+  EXPECT_THAT(Inserted, testing::ElementsAre(NewI));
+  EXPECT_THAT(Removed, testing::IsEmpty());
+  EXPECT_THAT(Moved, testing::IsEmpty());
+
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tmsri wrote:

A drive-by comment:  How about testing insertBefore and insertAfter?

https://github.com/llvm/llvm-project/pull/112965