[llvm] [SandboxIR] Add RegionPass/RegionPassManager (PR #110933)

[Arthur Eubanks via llvm-commits]

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@@ -86,6 +87,68 @@ define void @foo() {
 #endif
 }
 
+TEST_F(PassTest, RegionPass) {
+  auto *F = parseFunction(R"IR(
+define i8 @foo(i8 %v0, i8 %v1) {
+  %t0 = add i8 %v0, 1
+  %t1 = add i8 %t0, %v1, !sandboxvec !0
+  %t2 = add i8 %t1, %v1, !sandboxvec !0
+  ret i8 %t1
+}
+
+!0 = distinct !{!"sandboxregion"}
+)IR",
+                          "foo");
+
+  class TestPass final : public RegionPass {
+    unsigned &InstCount;
+
+  public:
+    TestPass(unsigned &InstCount)
+        : RegionPass("test-pass"), InstCount(InstCount) {}
+    bool runOnRegion(Region &R) final {
+      for ([[maybe_unused]] auto &Inst : R) {
+        ++InstCount;
+      }
+      return false;
+    }
+  };
+  unsigned InstCount = 0;
+  TestPass TPass(InstCount);
+  // Check getName(),
+  EXPECT_EQ(TPass.getName(), "test-pass");
+  // Check runOnRegion();
+  llvm::SmallVector<std::unique_ptr<Region>> Regions =
+      Region::createRegionsFromMD(*F);
+  ASSERT_EQ(Regions.size(), 1u);
+  TPass.runOnRegion(*Regions[0]);
+  EXPECT_EQ(InstCount, 2u);
+#ifndef NDEBUG
+  {
+    // Check print().
+    std::string Buff;
+    llvm::raw_string_ostream SS(Buff);
+    TPass.print(SS);
+    EXPECT_EQ(Buff, "test-pass");
+  }
+  {
+    // Check operator<<().
+    std::string Buff;
+    llvm::raw_string_ostream SS(Buff);
+    SS << TPass;
+    EXPECT_EQ(Buff, "test-pass");
+  }
+  // Check pass name assertions.
+  class TestNamePass final : public RegionPass {
+  public:
+    TestNamePass(llvm::StringRef Name) : RegionPass(Name) {}
+    bool runOnRegion(Region &F) { return false; }
+  };
+  EXPECT_DEATH(TestNamePass("white space"), ".*whitespace.*");
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aeubanks wrote:

I feel like the asserts are pretty self-explanatory and easy to fix if someone hits them. Maybe adding the reasoning behind those restrictions in comments around the asserts is good

https://github.com/llvm/llvm-project/pull/110933