From 85cdf54388d67674e4b896016ff2d9086668a4be Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ingo=20M=C3=BCller?= <ingomueller@google.com>
Date: Tue, 9 Jul 2024 13:24:45 +0000
Subject: [PATCH] XXX: Apply WIP patch. This should fix CI.

---
 .github/workflows/buildAndTestStructured.yml |   6 +
 cast.patch                                   | 124 +++++++++++++++++++
 2 files changed, 130 insertions(+)
 create mode 100644 cast.patch

diff --git a/.github/workflows/buildAndTestStructured.yml b/.github/workflows/buildAndTestStructured.yml
index 3e64d38e088d..0c42cb781015 100644
--- a/.github/workflows/buildAndTestStructured.yml
+++ b/.github/workflows/buildAndTestStructured.yml
@@ -49,6 +49,12 @@ jobs:
         path: sandbox
         submodules: recursive
 
+    - name: Patch LLVM with WIP patch for testing
+      run: |
+        cd ${STRUCTURED_MAIN_SRC_DIR}/third_party/llvm-project
+        patch -p1 < ../../cast.patch
+        git diff
+
     - name: Install Ninja
       uses: llvm/actions/install-ninja@6a57890d0e3f9f35dfc72e7e48bc5e1e527cdd6c # Jan 17
 
diff --git a/cast.patch b/cast.patch
new file mode 100644
index 000000000000..2e14b9c9fc58
--- /dev/null
+++ b/cast.patch
@@ -0,0 +1,124 @@
+commit 3ea3d4bed57c4f6a35bed044bca8c1277fa2bb17
+Author: lipracer <lipracer@gmail.com>
+Date:   Fri Mar 29 23:25:07 2024 +0800
+
+    [mlir] fix Undefined behavior in CastInfo::castFailed with From=<MLIR interface>
+    
+    Fixes https://github.com/llvm/llvm-project/issues/86647
+
+diff --git a/mlir/include/mlir/IR/OpDefinition.h b/mlir/include/mlir/IR/OpDefinition.h
+index bd68c2744574..5ba39b80b513 100644
+--- a/mlir/include/mlir/IR/OpDefinition.h
++++ b/mlir/include/mlir/IR/OpDefinition.h
+@@ -22,6 +22,7 @@
+ #include "mlir/IR/Dialect.h"
+ #include "mlir/IR/ODSSupport.h"
+ #include "mlir/IR/Operation.h"
++#include "llvm/Support/Casting.h"
+ #include "llvm/Support/PointerLikeTypeTraits.h"
+ 
+ #include <optional>
+@@ -2110,6 +2111,34 @@ struct DenseMapInfo<T,
+   }
+   static bool isEqual(T lhs, T rhs) { return lhs == rhs; }
+ };
++
++template <typename To, typename From>
++struct CastInfo<
++    To, From,
++    std::enable_if_t<
++        std::is_base_of_v<mlir::OpInterface<To, typename To::InterfaceTraits>,
++                          To> &&
++            std::is_base_of_v<mlir::OpInterface<std::remove_const_t<From>,
++                                                typename std::remove_const_t<
++                                                    From>::InterfaceTraits>,
++                              std::remove_const_t<From>>,
++        void>> : NullableValueCastFailed<To>,
++                 DefaultDoCastIfPossible<To, From, CastInfo<To, From>> {
++
++  static bool isPossible(From &val) {
++    if constexpr (std::is_same_v<To, From>)
++      return true;
++    else
++      return mlir::OpInterface<To, typename To::InterfaceTraits>::
++          InterfaceBase::classof(
++              const_cast<std::remove_const_t<From> &>(val).getOperation());
++  }
++
++  static To doCast(From &val) {
++    return To(const_cast<std::remove_const_t<From> &>(val).getOperation());
++  }
++};
++
+ } // namespace llvm
+ 
+ #endif
+diff --git a/mlir/tools/mlir-tblgen/OpInterfacesGen.cpp b/mlir/tools/mlir-tblgen/OpInterfacesGen.cpp
+index 2a7406f42f34..c6409e9ec30e 100644
+--- a/mlir/tools/mlir-tblgen/OpInterfacesGen.cpp
++++ b/mlir/tools/mlir-tblgen/OpInterfacesGen.cpp
+@@ -544,7 +544,8 @@ void InterfaceGenerator::emitInterfaceDecl(const Interface &interface) {
+   // Emit the main interface class declaration.
+   os << llvm::formatv("class {0} : public ::mlir::{3}<{1}, detail::{2}> {\n"
+                       "public:\n"
+-                      "  using ::mlir::{3}<{1}, detail::{2}>::{3};\n",
++                      "  using ::mlir::{3}<{1}, detail::{2}>::{3};\n"
++                      "  using InterfaceTraits = detail::{2};\n",
+                       interfaceName, interfaceName, interfaceTraitsName,
+                       interfaceBaseType);
+ 
+diff --git a/mlir/unittests/IR/InterfaceTest.cpp b/mlir/unittests/IR/InterfaceTest.cpp
+index 5ab4d9a10623..7012da669248 100644
+--- a/mlir/unittests/IR/InterfaceTest.cpp
++++ b/mlir/unittests/IR/InterfaceTest.cpp
+@@ -16,6 +16,9 @@
+ #include "../../test/lib/Dialect/Test/TestAttributes.h"
+ #include "../../test/lib/Dialect/Test/TestDialect.h"
+ #include "../../test/lib/Dialect/Test/TestTypes.h"
++#include "mlir/Dialect/Arith/IR/Arith.h"
++#include "mlir/Parser/Parser.h"
++#include "llvm/ADT/TypeSwitch.h"
+ 
+ using namespace mlir;
+ using namespace test;
+@@ -83,3 +86,40 @@ TEST(InterfaceTest, TestImplicitConversion) {
+   typeA = typeB;
+   EXPECT_EQ(typeA, typeB);
+ }
++
++TEST(OperationInterfaceTest, CastOpToInterface) {
++  DialectRegistry registry;
++  MLIRContext ctx;
++
++  const char *ir = R"MLIR(
++      func.func @map(%arg : tensor<1xi64>) {
++        %0 = arith.constant dense<[10]> : tensor<1xi64>
++        %1 = arith.addi %arg, %0 : tensor<1xi64>
++        return
++      }
++    )MLIR";
++
++  registry.insert<func::FuncDialect, arith::ArithDialect>();
++  ctx.appendDialectRegistry(registry);
++  OwningOpRef<ModuleOp> module = parseSourceString<ModuleOp>(ir, &ctx);
++  Operation &op = cast<func::FuncOp>(module->front()).getBody().front().front();
++
++  OpAsmOpInterface interface = llvm::cast<OpAsmOpInterface>(op);
++
++  bool constantOp =
++      llvm::TypeSwitch<OpAsmOpInterface, bool>(interface)
++          .Case<VectorUnrollOpInterface, arith::ConstantOp>([&](auto op) {
++            return std::is_same_v<decltype(op), arith::ConstantOp>;
++          });
++
++  EXPECT_TRUE(constantOp);
++
++  EXPECT_FALSE(llvm::isa<VectorUnrollOpInterface>(interface));
++  EXPECT_FALSE(llvm::dyn_cast<VectorUnrollOpInterface>(interface));
++
++  EXPECT_TRUE(llvm::isa<InferTypeOpInterface>(interface));
++  EXPECT_TRUE(llvm::dyn_cast<InferTypeOpInterface>(interface));
++
++  EXPECT_TRUE(llvm::isa<OpAsmOpInterface>(interface));
++  EXPECT_TRUE(llvm::dyn_cast<OpAsmOpInterface>(interface));
++}