[llvm] Make llvm::Any similar to std::any

This facilitates replacing llvm::Any with std::any.
- Deprecate any_isa in favor of using any_cast(Any*) and checking for
  nullptr because C++17 has no any_isa.
- Remove the assert from any_cast(Any*), so it returns nullptr if the
  type is not correct. This aligns it with std::any_cast(any*).

Use any_cast(Any*) throughout LLVM instead of checks with any_isa.

This is the first part outlined in
https://discourse.llvm.org/t/rfc-switching-from-llvm-any-to-std-any/67176

Differential Revision: https://reviews.llvm.org/D139973

1 files changed, 5 insertions, 4 deletions

diff --git a/llvm/lib/Transforms/Scalar/LoopPassManager.cpp b/llvm/lib/Transforms/Scalar/LoopPassManager.cpp
index fadd070..c98b94b 100644
--- a/llvm/lib/Transforms/Scalar/LoopPassManager.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopPassManager.cpp
@@ -269,10 +269,11 @@ PreservedAnalyses FunctionToLoopPassAdaptor::run(Function &F,
   PI.pushBeforeNonSkippedPassCallback([&LAR, &LI](StringRef PassID, Any IR) {
     if (isSpecialPass(PassID, {"PassManager"}))
       return;
-    assert(any_isa<const Loop *>(IR) || any_isa<const LoopNest *>(IR));
-    const Loop *L = any_isa<const Loop *>(IR)
-                        ? any_cast<const Loop *>(IR)
-                        : &any_cast<const LoopNest *>(IR)->getOutermostLoop();
+    assert(any_cast<const Loop *>(&IR) || any_cast<const LoopNest *>(&IR));
+    const Loop **LPtr = any_cast<const Loop *>(&IR);
+    const Loop *L = LPtr ? *LPtr : nullptr;
+    if (!L)
+      L = &any_cast<const LoopNest *>(IR)->getOutermostLoop();
     assert(L && "Loop should be valid for printing");
 
     // Verify the loop structure and LCSSA form before visiting the loop.