[llvm] [SandboxVec] Tag insts in a Region with metadata. (PR #109353)

[Sriraman Tallam via llvm-commits]

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@@ -79,3 +78,58 @@ define i8 @foo(i8 %v0, i8 %v1) {
   EXPECT_EQ(Rgn, Other);
 #endif
 }
+
+TEST_F(RegionTest, MetadataFromIR) {
+  parseIR(C, R"IR(
+define i8 @foo(i8 %v0, i8 %v1) {
+  %t0 = add i8 %v0, 1, !sbvec !0
+  %t1 = add i8 %t0, %v1, !sbvec !1
+  %t2 = add i8 %t1, %v1, !sbvec !1
+  ret i8 %t2
+}
+
+!0 = distinct !{!"region"}
+!1 = distinct !{!"region"}
+)IR");
+  llvm::Function *LLVMF = &*M->getFunction("foo");
+  sandboxir::Context Ctx(C);
+  auto *F = Ctx.createFunction(LLVMF);
+  auto *BB = &*F->begin();
+  auto It = BB->begin();
+  auto *T0 = cast<sandboxir::Instruction>(&*It++);
+  auto *T1 = cast<sandboxir::Instruction>(&*It++);
+  auto *T2 = cast<sandboxir::Instruction>(&*It++);
+
+  SmallVector<std::unique_ptr<sandboxir::Region>> Regions =
+      sandboxir::Region::createRegionsFromMD(*F);
+  EXPECT_THAT(Regions[0]->insts(), testing::UnorderedElementsAre(T0));
+  EXPECT_THAT(Regions[1]->insts(), testing::UnorderedElementsAre(T1, T2));
+}
+
+TEST_F(RegionTest, MetadataRoundTrip) {
+  parseIR(C, R"IR(
+define i8 @foo(i8 %v0, i8 %v1) {
+  %t0 = add i8 %v0, 1
+  %t1 = add i8 %t0, %v1
+  ret i8 %t1
+}
+)IR");
+  llvm::Function *LLVMF = &*M->getFunction("foo");
+  sandboxir::Context Ctx(C);
+  auto *F = Ctx.createFunction(LLVMF);
+  auto *BB = &*F->begin();
+  auto It = BB->begin();
+  auto *T0 = cast<sandboxir::Instruction>(&*It++);
+  auto *T1 = cast<sandboxir::Instruction>(&*It++);
+
+  sandboxir::Region Rgn(Ctx);
+  Rgn.add(T0);
+  Rgn.add(T1);
+
+  SmallVector<std::unique_ptr<sandboxir::Region>> Regions =
+      sandboxir::Region::createRegionsFromMD(*F);
+  ASSERT_EQ(1U, Regions.size());
+#ifndef NDEBUG
+  EXPECT_EQ(Rgn, *Regions[0].get());
+#endif
----------------
tmsri wrote:

How about dumping the IR and explicitly check for required number of "distinct !{!"region"}" and create more than one region?

https://github.com/llvm/llvm-project/pull/109353